diff options
Diffstat (limited to 'crypto/asymmetric_keys')
26 files changed, 5929 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig new file mode 100644 index 000000000..59ec726b7 --- /dev/null +++ b/crypto/asymmetric_keys/Kconfig @@ -0,0 +1,89 @@ +# SPDX-License-Identifier: GPL-2.0 +menuconfig ASYMMETRIC_KEY_TYPE + bool "Asymmetric (public-key cryptographic) key type" + depends on KEYS + help + This option provides support for a key type that holds the data for + the asymmetric keys used for public key cryptographic operations such + as encryption, decryption, signature generation and signature + verification. + +if ASYMMETRIC_KEY_TYPE + +config ASYMMETRIC_PUBLIC_KEY_SUBTYPE + tristate "Asymmetric public-key crypto algorithm subtype" + select MPILIB + select CRYPTO_HASH_INFO + select CRYPTO_AKCIPHER + select CRYPTO_HASH + help + This option provides support for asymmetric public key type handling. + If signature generation and/or verification are to be used, + appropriate hash algorithms (such as SHA-1) must be available. + ENOPKG will be reported if the requisite algorithm is unavailable. + +config X509_CERTIFICATE_PARSER + tristate "X.509 certificate parser" + depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE + select ASN1 + select OID_REGISTRY + help + This option provides support for parsing X.509 format blobs for key + data and provides the ability to instantiate a crypto key from a + public key packet found inside the certificate. + +config PKCS8_PRIVATE_KEY_PARSER + tristate "PKCS#8 private key parser" + depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE + select ASN1 + select OID_REGISTRY + help + This option provides support for parsing PKCS#8 format blobs for + private key data and provides the ability to instantiate a crypto key + from that data. + +config PKCS7_MESSAGE_PARSER + tristate "PKCS#7 message parser" + depends on X509_CERTIFICATE_PARSER + select CRYPTO_HASH + select ASN1 + select OID_REGISTRY + help + This option provides support for parsing PKCS#7 format messages for + signature data and provides the ability to verify the signature. + +config PKCS7_TEST_KEY + tristate "PKCS#7 testing key type" + depends on SYSTEM_DATA_VERIFICATION + help + This option provides a type of key that can be loaded up from a + PKCS#7 message - provided the message is signed by a trusted key. If + it is, the PKCS#7 wrapper is discarded and reading the key returns + just the payload. If it isn't, adding the key will fail with an + error. + + This is intended for testing the PKCS#7 parser. + +config SIGNED_PE_FILE_VERIFICATION + bool "Support for PE file signature verification" + depends on PKCS7_MESSAGE_PARSER=y + depends on SYSTEM_DATA_VERIFICATION + select CRYPTO_HASH + select ASN1 + select OID_REGISTRY + help + This option provides support for verifying the signature(s) on a + signed PE binary. + +config FIPS_SIGNATURE_SELFTEST + tristate "Run FIPS selftests on the X.509+PKCS7 signature verification" + help + This option causes some selftests to be run on the signature + verification code, using some built in data. This is required + for FIPS. + depends on KEYS + depends on ASYMMETRIC_KEY_TYPE + depends on PKCS7_MESSAGE_PARSER=X509_CERTIFICATE_PARSER + depends on X509_CERTIFICATE_PARSER + +endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile new file mode 100644 index 000000000..1a273d6df --- /dev/null +++ b/crypto/asymmetric_keys/Makefile @@ -0,0 +1,79 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for asymmetric cryptographic keys +# + +obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o + +asymmetric_keys-y := \ + asymmetric_type.o \ + restrict.o \ + signature.o + +obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o + +# +# X.509 Certificate handling +# +obj-$(CONFIG_X509_CERTIFICATE_PARSER) += x509_key_parser.o +x509_key_parser-y := \ + x509.asn1.o \ + x509_akid.asn1.o \ + x509_cert_parser.o \ + x509_loader.o \ + x509_public_key.o +obj-$(CONFIG_FIPS_SIGNATURE_SELFTEST) += x509_selftest.o +x509_selftest-y += selftest.o + +$(obj)/x509_cert_parser.o: \ + $(obj)/x509.asn1.h \ + $(obj)/x509_akid.asn1.h + +$(obj)/x509.asn1.o: $(obj)/x509.asn1.c $(obj)/x509.asn1.h +$(obj)/x509_akid.asn1.o: $(obj)/x509_akid.asn1.c $(obj)/x509_akid.asn1.h + +# +# PKCS#8 private key handling +# +obj-$(CONFIG_PKCS8_PRIVATE_KEY_PARSER) += pkcs8_key_parser.o +pkcs8_key_parser-y := \ + pkcs8.asn1.o \ + pkcs8_parser.o + +$(obj)/pkcs8_parser.o: $(obj)/pkcs8.asn1.h +$(obj)/pkcs8-asn1.o: $(obj)/pkcs8.asn1.c $(obj)/pkcs8.asn1.h + +clean-files += pkcs8.asn1.c pkcs8.asn1.h + +# +# PKCS#7 message handling +# +obj-$(CONFIG_PKCS7_MESSAGE_PARSER) += pkcs7_message.o +pkcs7_message-y := \ + pkcs7.asn1.o \ + pkcs7_parser.o \ + pkcs7_trust.o \ + pkcs7_verify.o + +$(obj)/pkcs7_parser.o: $(obj)/pkcs7.asn1.h +$(obj)/pkcs7.asn1.o: $(obj)/pkcs7.asn1.c $(obj)/pkcs7.asn1.h + +# +# PKCS#7 parser testing key +# +obj-$(CONFIG_PKCS7_TEST_KEY) += pkcs7_test_key.o +pkcs7_test_key-y := \ + pkcs7_key_type.o + +# +# Signed PE binary-wrapped key handling +# +obj-$(CONFIG_SIGNED_PE_FILE_VERIFICATION) += verify_signed_pefile.o + +verify_signed_pefile-y := \ + verify_pefile.o \ + mscode_parser.o \ + mscode.asn1.o + +$(obj)/mscode_parser.o: $(obj)/mscode.asn1.h $(obj)/mscode.asn1.h +$(obj)/mscode.asn1.o: $(obj)/mscode.asn1.c $(obj)/mscode.asn1.h diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h new file mode 100644 index 000000000..dc854cb73 --- /dev/null +++ b/crypto/asymmetric_keys/asymmetric_keys.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* Internal definitions for asymmetric key type + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <keys/asymmetric-type.h> + +extern struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id); + +extern int __asymmetric_key_hex_to_key_id(const char *id, + struct asymmetric_key_id *match_id, + size_t hexlen); + +extern int asymmetric_key_eds_op(struct kernel_pkey_params *params, + const void *in, void *out); diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c new file mode 100644 index 000000000..a5da8ccd3 --- /dev/null +++ b/crypto/asymmetric_keys/asymmetric_type.c @@ -0,0 +1,684 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Asymmetric public-key cryptography key type + * + * See Documentation/crypto/asymmetric-keys.rst + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ +#include <keys/asymmetric-subtype.h> +#include <keys/asymmetric-parser.h> +#include <crypto/public_key.h> +#include <linux/seq_file.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/ctype.h> +#include <keys/system_keyring.h> +#include <keys/user-type.h> +#include "asymmetric_keys.h" + + +const char *const key_being_used_for[NR__KEY_BEING_USED_FOR] = { + [VERIFYING_MODULE_SIGNATURE] = "mod sig", + [VERIFYING_FIRMWARE_SIGNATURE] = "firmware sig", + [VERIFYING_KEXEC_PE_SIGNATURE] = "kexec PE sig", + [VERIFYING_KEY_SIGNATURE] = "key sig", + [VERIFYING_KEY_SELF_SIGNATURE] = "key self sig", + [VERIFYING_UNSPECIFIED_SIGNATURE] = "unspec sig", +}; +EXPORT_SYMBOL_GPL(key_being_used_for); + +static LIST_HEAD(asymmetric_key_parsers); +static DECLARE_RWSEM(asymmetric_key_parsers_sem); + +/** + * find_asymmetric_key - Find a key by ID. + * @keyring: The keys to search. + * @id_0: The first ID to look for or NULL. + * @id_1: The second ID to look for or NULL, matched together with @id_0 + * against @keyring keys' id[0] and id[1]. + * @id_2: The fallback ID to match against @keyring keys' id[2] if both of the + * other IDs are NULL. + * @partial: Use partial match for @id_0 and @id_1 if true, exact if false. + * + * Find a key in the given keyring by identifier. The preferred identifier is + * the id_0 and the fallback identifier is the id_1. If both are given, the + * former is matched (exactly or partially) against either of the sought key's + * identifiers and the latter must match the found key's second identifier + * exactly. If both are missing, id_2 must match the sought key's third + * identifier exactly. + */ +struct key *find_asymmetric_key(struct key *keyring, + const struct asymmetric_key_id *id_0, + const struct asymmetric_key_id *id_1, + const struct asymmetric_key_id *id_2, + bool partial) +{ + struct key *key; + key_ref_t ref; + const char *lookup; + char *req, *p; + int len; + + WARN_ON(!id_0 && !id_1 && !id_2); + + if (id_0) { + lookup = id_0->data; + len = id_0->len; + } else if (id_1) { + lookup = id_1->data; + len = id_1->len; + } else { + lookup = id_2->data; + len = id_2->len; + } + + /* Construct an identifier "id:<keyid>". */ + p = req = kmalloc(2 + 1 + len * 2 + 1, GFP_KERNEL); + if (!req) + return ERR_PTR(-ENOMEM); + + if (!id_0 && !id_1) { + *p++ = 'd'; + *p++ = 'n'; + } else if (partial) { + *p++ = 'i'; + *p++ = 'd'; + } else { + *p++ = 'e'; + *p++ = 'x'; + } + *p++ = ':'; + p = bin2hex(p, lookup, len); + *p = 0; + + pr_debug("Look up: \"%s\"\n", req); + + ref = keyring_search(make_key_ref(keyring, 1), + &key_type_asymmetric, req, true); + if (IS_ERR(ref)) + pr_debug("Request for key '%s' err %ld\n", req, PTR_ERR(ref)); + kfree(req); + + if (IS_ERR(ref)) { + switch (PTR_ERR(ref)) { + /* Hide some search errors */ + case -EACCES: + case -ENOTDIR: + case -EAGAIN: + return ERR_PTR(-ENOKEY); + default: + return ERR_CAST(ref); + } + } + + key = key_ref_to_ptr(ref); + if (id_0 && id_1) { + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + + if (!kids->id[1]) { + pr_debug("First ID matches, but second is missing\n"); + goto reject; + } + if (!asymmetric_key_id_same(id_1, kids->id[1])) { + pr_debug("First ID matches, but second does not\n"); + goto reject; + } + } + + pr_devel("<==%s() = 0 [%x]\n", __func__, key_serial(key)); + return key; + +reject: + key_put(key); + return ERR_PTR(-EKEYREJECTED); +} +EXPORT_SYMBOL_GPL(find_asymmetric_key); + +/** + * asymmetric_key_generate_id: Construct an asymmetric key ID + * @val_1: First binary blob + * @len_1: Length of first binary blob + * @val_2: Second binary blob + * @len_2: Length of second binary blob + * + * Construct an asymmetric key ID from a pair of binary blobs. + */ +struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, + size_t len_1, + const void *val_2, + size_t len_2) +{ + struct asymmetric_key_id *kid; + + kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2, + GFP_KERNEL); + if (!kid) + return ERR_PTR(-ENOMEM); + kid->len = len_1 + len_2; + memcpy(kid->data, val_1, len_1); + memcpy(kid->data + len_1, val_2, len_2); + return kid; +} +EXPORT_SYMBOL_GPL(asymmetric_key_generate_id); + +/** + * asymmetric_key_id_same - Return true if two asymmetric keys IDs are the same. + * @kid1: The key ID to compare + * @kid2: The key ID to compare + */ +bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2) +{ + if (!kid1 || !kid2) + return false; + if (kid1->len != kid2->len) + return false; + return memcmp(kid1->data, kid2->data, kid1->len) == 0; +} +EXPORT_SYMBOL_GPL(asymmetric_key_id_same); + +/** + * asymmetric_key_id_partial - Return true if two asymmetric keys IDs + * partially match + * @kid1: The key ID to compare + * @kid2: The key ID to compare + */ +bool asymmetric_key_id_partial(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2) +{ + if (!kid1 || !kid2) + return false; + if (kid1->len < kid2->len) + return false; + return memcmp(kid1->data + (kid1->len - kid2->len), + kid2->data, kid2->len) == 0; +} +EXPORT_SYMBOL_GPL(asymmetric_key_id_partial); + +/** + * asymmetric_match_key_ids - Search asymmetric key IDs 1 & 2 + * @kids: The pair of key IDs to check + * @match_id: The key ID we're looking for + * @match: The match function to use + */ +static bool asymmetric_match_key_ids( + const struct asymmetric_key_ids *kids, + const struct asymmetric_key_id *match_id, + bool (*match)(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2)) +{ + int i; + + if (!kids || !match_id) + return false; + for (i = 0; i < 2; i++) + if (match(kids->id[i], match_id)) + return true; + return false; +} + +/* helper function can be called directly with pre-allocated memory */ +inline int __asymmetric_key_hex_to_key_id(const char *id, + struct asymmetric_key_id *match_id, + size_t hexlen) +{ + match_id->len = hexlen; + return hex2bin(match_id->data, id, hexlen); +} + +/** + * asymmetric_key_hex_to_key_id - Convert a hex string into a key ID. + * @id: The ID as a hex string. + */ +struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id) +{ + struct asymmetric_key_id *match_id; + size_t asciihexlen; + int ret; + + if (!*id) + return ERR_PTR(-EINVAL); + asciihexlen = strlen(id); + if (asciihexlen & 1) + return ERR_PTR(-EINVAL); + + match_id = kmalloc(sizeof(struct asymmetric_key_id) + asciihexlen / 2, + GFP_KERNEL); + if (!match_id) + return ERR_PTR(-ENOMEM); + ret = __asymmetric_key_hex_to_key_id(id, match_id, asciihexlen / 2); + if (ret < 0) { + kfree(match_id); + return ERR_PTR(-EINVAL); + } + return match_id; +} + +/* + * Match asymmetric keys by an exact match on one of the first two IDs. + */ +static bool asymmetric_key_cmp(const struct key *key, + const struct key_match_data *match_data) +{ + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *match_id = match_data->preparsed; + + return asymmetric_match_key_ids(kids, match_id, + asymmetric_key_id_same); +} + +/* + * Match asymmetric keys by a partial match on one of the first two IDs. + */ +static bool asymmetric_key_cmp_partial(const struct key *key, + const struct key_match_data *match_data) +{ + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *match_id = match_data->preparsed; + + return asymmetric_match_key_ids(kids, match_id, + asymmetric_key_id_partial); +} + +/* + * Match asymmetric keys by an exact match on the third IDs. + */ +static bool asymmetric_key_cmp_name(const struct key *key, + const struct key_match_data *match_data) +{ + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *match_id = match_data->preparsed; + + return kids && asymmetric_key_id_same(kids->id[2], match_id); +} + +/* + * Preparse the match criterion. If we don't set lookup_type and cmp, + * the default will be an exact match on the key description. + * + * There are some specifiers for matching key IDs rather than by the key + * description: + * + * "id:<id>" - find a key by partial match on one of the first two IDs + * "ex:<id>" - find a key by exact match on one of the first two IDs + * "dn:<id>" - find a key by exact match on the third ID + * + * These have to be searched by iteration rather than by direct lookup because + * the key is hashed according to its description. + */ +static int asymmetric_key_match_preparse(struct key_match_data *match_data) +{ + struct asymmetric_key_id *match_id; + const char *spec = match_data->raw_data; + const char *id; + bool (*cmp)(const struct key *, const struct key_match_data *) = + asymmetric_key_cmp; + + if (!spec || !*spec) + return -EINVAL; + if (spec[0] == 'i' && + spec[1] == 'd' && + spec[2] == ':') { + id = spec + 3; + cmp = asymmetric_key_cmp_partial; + } else if (spec[0] == 'e' && + spec[1] == 'x' && + spec[2] == ':') { + id = spec + 3; + } else if (spec[0] == 'd' && + spec[1] == 'n' && + spec[2] == ':') { + id = spec + 3; + cmp = asymmetric_key_cmp_name; + } else { + goto default_match; + } + + match_id = asymmetric_key_hex_to_key_id(id); + if (IS_ERR(match_id)) + return PTR_ERR(match_id); + + match_data->preparsed = match_id; + match_data->cmp = cmp; + match_data->lookup_type = KEYRING_SEARCH_LOOKUP_ITERATE; + return 0; + +default_match: + return 0; +} + +/* + * Free the preparsed the match criterion. + */ +static void asymmetric_key_match_free(struct key_match_data *match_data) +{ + kfree(match_data->preparsed); +} + +/* + * Describe the asymmetric key + */ +static void asymmetric_key_describe(const struct key *key, struct seq_file *m) +{ + const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + const struct asymmetric_key_ids *kids = asymmetric_key_ids(key); + const struct asymmetric_key_id *kid; + const unsigned char *p; + int n; + + seq_puts(m, key->description); + + if (subtype) { + seq_puts(m, ": "); + subtype->describe(key, m); + + if (kids && kids->id[1]) { + kid = kids->id[1]; + seq_putc(m, ' '); + n = kid->len; + p = kid->data; + if (n > 4) { + p += n - 4; + n = 4; + } + seq_printf(m, "%*phN", n, p); + } + + seq_puts(m, " ["); + /* put something here to indicate the key's capabilities */ + seq_putc(m, ']'); + } +} + +/* + * Preparse a asymmetric payload to get format the contents appropriately for the + * internal payload to cut down on the number of scans of the data performed. + * + * We also generate a proposed description from the contents of the key that + * can be used to name the key if the user doesn't want to provide one. + */ +static int asymmetric_key_preparse(struct key_preparsed_payload *prep) +{ + struct asymmetric_key_parser *parser; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (prep->datalen == 0) + return -EINVAL; + + down_read(&asymmetric_key_parsers_sem); + + ret = -EBADMSG; + list_for_each_entry(parser, &asymmetric_key_parsers, link) { + pr_debug("Trying parser '%s'\n", parser->name); + + ret = parser->parse(prep); + if (ret != -EBADMSG) { + pr_debug("Parser recognised the format (ret %d)\n", + ret); + break; + } + } + + up_read(&asymmetric_key_parsers_sem); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} + +/* + * Clean up the key ID list + */ +static void asymmetric_key_free_kids(struct asymmetric_key_ids *kids) +{ + int i; + + if (kids) { + for (i = 0; i < ARRAY_SIZE(kids->id); i++) + kfree(kids->id[i]); + kfree(kids); + } +} + +/* + * Clean up the preparse data + */ +static void asymmetric_key_free_preparse(struct key_preparsed_payload *prep) +{ + struct asymmetric_key_subtype *subtype = prep->payload.data[asym_subtype]; + struct asymmetric_key_ids *kids = prep->payload.data[asym_key_ids]; + + pr_devel("==>%s()\n", __func__); + + if (subtype) { + subtype->destroy(prep->payload.data[asym_crypto], + prep->payload.data[asym_auth]); + module_put(subtype->owner); + } + asymmetric_key_free_kids(kids); + kfree(prep->description); +} + +/* + * dispose of the data dangling from the corpse of a asymmetric key + */ +static void asymmetric_key_destroy(struct key *key) +{ + struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + struct asymmetric_key_ids *kids = key->payload.data[asym_key_ids]; + void *data = key->payload.data[asym_crypto]; + void *auth = key->payload.data[asym_auth]; + + key->payload.data[asym_crypto] = NULL; + key->payload.data[asym_subtype] = NULL; + key->payload.data[asym_key_ids] = NULL; + key->payload.data[asym_auth] = NULL; + + if (subtype) { + subtype->destroy(data, auth); + module_put(subtype->owner); + } + + asymmetric_key_free_kids(kids); +} + +static struct key_restriction *asymmetric_restriction_alloc( + key_restrict_link_func_t check, + struct key *key) +{ + struct key_restriction *keyres = + kzalloc(sizeof(struct key_restriction), GFP_KERNEL); + + if (!keyres) + return ERR_PTR(-ENOMEM); + + keyres->check = check; + keyres->key = key; + keyres->keytype = &key_type_asymmetric; + + return keyres; +} + +/* + * look up keyring restrict functions for asymmetric keys + */ +static struct key_restriction *asymmetric_lookup_restriction( + const char *restriction) +{ + char *restrict_method; + char *parse_buf; + char *next; + struct key_restriction *ret = ERR_PTR(-EINVAL); + + if (strcmp("builtin_trusted", restriction) == 0) + return asymmetric_restriction_alloc( + restrict_link_by_builtin_trusted, NULL); + + if (strcmp("builtin_and_secondary_trusted", restriction) == 0) + return asymmetric_restriction_alloc( + restrict_link_by_builtin_and_secondary_trusted, NULL); + + parse_buf = kstrndup(restriction, PAGE_SIZE, GFP_KERNEL); + if (!parse_buf) + return ERR_PTR(-ENOMEM); + + next = parse_buf; + restrict_method = strsep(&next, ":"); + + if ((strcmp(restrict_method, "key_or_keyring") == 0) && next) { + char *key_text; + key_serial_t serial; + struct key *key; + key_restrict_link_func_t link_fn = + restrict_link_by_key_or_keyring; + bool allow_null_key = false; + + key_text = strsep(&next, ":"); + + if (next) { + if (strcmp(next, "chain") != 0) + goto out; + + link_fn = restrict_link_by_key_or_keyring_chain; + allow_null_key = true; + } + + if (kstrtos32(key_text, 0, &serial) < 0) + goto out; + + if ((serial == 0) && allow_null_key) { + key = NULL; + } else { + key = key_lookup(serial); + if (IS_ERR(key)) { + ret = ERR_CAST(key); + goto out; + } + } + + ret = asymmetric_restriction_alloc(link_fn, key); + if (IS_ERR(ret)) + key_put(key); + } + +out: + kfree(parse_buf); + return ret; +} + +int asymmetric_key_eds_op(struct kernel_pkey_params *params, + const void *in, void *out) +{ + const struct asymmetric_key_subtype *subtype; + struct key *key = params->key; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (key->type != &key_type_asymmetric) + return -EINVAL; + subtype = asymmetric_key_subtype(key); + if (!subtype || + !key->payload.data[0]) + return -EINVAL; + if (!subtype->eds_op) + return -ENOTSUPP; + + ret = subtype->eds_op(params, in, out); + + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} + +static int asymmetric_key_verify_signature(struct kernel_pkey_params *params, + const void *in, const void *in2) +{ + struct public_key_signature sig = { + .s_size = params->in2_len, + .digest_size = params->in_len, + .encoding = params->encoding, + .hash_algo = params->hash_algo, + .digest = (void *)in, + .s = (void *)in2, + }; + + return verify_signature(params->key, &sig); +} + +struct key_type key_type_asymmetric = { + .name = "asymmetric", + .preparse = asymmetric_key_preparse, + .free_preparse = asymmetric_key_free_preparse, + .instantiate = generic_key_instantiate, + .match_preparse = asymmetric_key_match_preparse, + .match_free = asymmetric_key_match_free, + .destroy = asymmetric_key_destroy, + .describe = asymmetric_key_describe, + .lookup_restriction = asymmetric_lookup_restriction, + .asym_query = query_asymmetric_key, + .asym_eds_op = asymmetric_key_eds_op, + .asym_verify_signature = asymmetric_key_verify_signature, +}; +EXPORT_SYMBOL_GPL(key_type_asymmetric); + +/** + * register_asymmetric_key_parser - Register a asymmetric key blob parser + * @parser: The parser to register + */ +int register_asymmetric_key_parser(struct asymmetric_key_parser *parser) +{ + struct asymmetric_key_parser *cursor; + int ret; + + down_write(&asymmetric_key_parsers_sem); + + list_for_each_entry(cursor, &asymmetric_key_parsers, link) { + if (strcmp(cursor->name, parser->name) == 0) { + pr_err("Asymmetric key parser '%s' already registered\n", + parser->name); + ret = -EEXIST; + goto out; + } + } + + list_add_tail(&parser->link, &asymmetric_key_parsers); + + pr_notice("Asymmetric key parser '%s' registered\n", parser->name); + ret = 0; + +out: + up_write(&asymmetric_key_parsers_sem); + return ret; +} +EXPORT_SYMBOL_GPL(register_asymmetric_key_parser); + +/** + * unregister_asymmetric_key_parser - Unregister a asymmetric key blob parser + * @parser: The parser to unregister + */ +void unregister_asymmetric_key_parser(struct asymmetric_key_parser *parser) +{ + down_write(&asymmetric_key_parsers_sem); + list_del(&parser->link); + up_write(&asymmetric_key_parsers_sem); + + pr_notice("Asymmetric key parser '%s' unregistered\n", parser->name); +} +EXPORT_SYMBOL_GPL(unregister_asymmetric_key_parser); + +/* + * Module stuff + */ +static int __init asymmetric_key_init(void) +{ + return register_key_type(&key_type_asymmetric); +} + +static void __exit asymmetric_key_cleanup(void) +{ + unregister_key_type(&key_type_asymmetric); +} + +module_init(asymmetric_key_init); +module_exit(asymmetric_key_cleanup); diff --git a/crypto/asymmetric_keys/mscode.asn1 b/crypto/asymmetric_keys/mscode.asn1 new file mode 100644 index 000000000..6d09ba48c --- /dev/null +++ b/crypto/asymmetric_keys/mscode.asn1 @@ -0,0 +1,28 @@ +--- Microsoft individual code signing data blob parser +--- +--- Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. +--- Written by David Howells (dhowells@redhat.com) +--- +--- This program is free software; you can redistribute it and/or +--- modify it under the terms of the GNU General Public Licence +--- as published by the Free Software Foundation; either version +--- 2 of the Licence, or (at your option) any later version. +--- + +MSCode ::= SEQUENCE { + type SEQUENCE { + contentType ContentType, + parameters ANY + }, + content SEQUENCE { + digestAlgorithm DigestAlgorithmIdentifier, + digest OCTET STRING ({ mscode_note_digest }) + } +} + +ContentType ::= OBJECT IDENTIFIER ({ mscode_note_content_type }) + +DigestAlgorithmIdentifier ::= SEQUENCE { + algorithm OBJECT IDENTIFIER ({ mscode_note_digest_algo }), + parameters ANY OPTIONAL +} diff --git a/crypto/asymmetric_keys/mscode_parser.c b/crypto/asymmetric_keys/mscode_parser.c new file mode 100644 index 000000000..839591ad2 --- /dev/null +++ b/crypto/asymmetric_keys/mscode_parser.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Parse a Microsoft Individual Code Signing blob + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "MSCODE: "fmt +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/oid_registry.h> +#include <crypto/pkcs7.h> +#include "verify_pefile.h" +#include "mscode.asn1.h" + +/* + * Parse a Microsoft Individual Code Signing blob + */ +int mscode_parse(void *_ctx, const void *content_data, size_t data_len, + size_t asn1hdrlen) +{ + struct pefile_context *ctx = _ctx; + + content_data -= asn1hdrlen; + data_len += asn1hdrlen; + pr_devel("Data: %zu [%*ph]\n", data_len, (unsigned)(data_len), + content_data); + + return asn1_ber_decoder(&mscode_decoder, ctx, content_data, data_len); +} + +/* + * Check the content type OID + */ +int mscode_note_content_type(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + enum OID oid; + + oid = look_up_OID(value, vlen); + if (oid == OID__NR) { + char buffer[50]; + + sprint_oid(value, vlen, buffer, sizeof(buffer)); + pr_err("Unknown OID: %s\n", buffer); + return -EBADMSG; + } + + /* + * pesign utility had a bug where it was putting + * OID_msIndividualSPKeyPurpose instead of OID_msPeImageDataObjId + * So allow both OIDs. + */ + if (oid != OID_msPeImageDataObjId && + oid != OID_msIndividualSPKeyPurpose) { + pr_err("Unexpected content type OID %u\n", oid); + return -EBADMSG; + } + + return 0; +} + +/* + * Note the digest algorithm OID + */ +int mscode_note_digest_algo(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pefile_context *ctx = context; + char buffer[50]; + enum OID oid; + + oid = look_up_OID(value, vlen); + switch (oid) { + case OID_md4: + ctx->digest_algo = "md4"; + break; + case OID_md5: + ctx->digest_algo = "md5"; + break; + case OID_sha1: + ctx->digest_algo = "sha1"; + break; + case OID_sha256: + ctx->digest_algo = "sha256"; + break; + case OID_sha384: + ctx->digest_algo = "sha384"; + break; + case OID_sha512: + ctx->digest_algo = "sha512"; + break; + case OID_sha224: + ctx->digest_algo = "sha224"; + break; + + case OID__NR: + sprint_oid(value, vlen, buffer, sizeof(buffer)); + pr_err("Unknown OID: %s\n", buffer); + return -EBADMSG; + + default: + pr_err("Unsupported content type: %u\n", oid); + return -ENOPKG; + } + + return 0; +} + +/* + * Note the digest we're guaranteeing with this certificate + */ +int mscode_note_digest(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pefile_context *ctx = context; + + ctx->digest = kmemdup(value, vlen, GFP_KERNEL); + if (!ctx->digest) + return -ENOMEM; + + ctx->digest_len = vlen; + + return 0; +} diff --git a/crypto/asymmetric_keys/pkcs7.asn1 b/crypto/asymmetric_keys/pkcs7.asn1 new file mode 100644 index 000000000..1eca740b8 --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7.asn1 @@ -0,0 +1,135 @@ +PKCS7ContentInfo ::= SEQUENCE { + contentType ContentType ({ pkcs7_check_content_type }), + content [0] EXPLICIT SignedData OPTIONAL +} + +ContentType ::= OBJECT IDENTIFIER ({ pkcs7_note_OID }) + +SignedData ::= SEQUENCE { + version INTEGER ({ pkcs7_note_signeddata_version }), + digestAlgorithms DigestAlgorithmIdentifiers, + contentInfo ContentInfo ({ pkcs7_note_content }), + certificates CHOICE { + certSet [0] IMPLICIT ExtendedCertificatesAndCertificates, + certSequence [2] IMPLICIT Certificates + } OPTIONAL ({ pkcs7_note_certificate_list }), + crls CHOICE { + crlSet [1] IMPLICIT CertificateRevocationLists, + crlSequence [3] IMPLICIT CRLSequence + } OPTIONAL, + signerInfos SignerInfos +} + +ContentInfo ::= SEQUENCE { + contentType ContentType ({ pkcs7_note_OID }), + content [0] EXPLICIT Data OPTIONAL +} + +Data ::= ANY ({ pkcs7_note_data }) + +DigestAlgorithmIdentifiers ::= CHOICE { + daSet SET OF DigestAlgorithmIdentifier, + daSequence SEQUENCE OF DigestAlgorithmIdentifier +} + +DigestAlgorithmIdentifier ::= SEQUENCE { + algorithm OBJECT IDENTIFIER ({ pkcs7_note_OID }), + parameters ANY OPTIONAL +} + +-- +-- Certificates and certificate lists +-- +ExtendedCertificatesAndCertificates ::= SET OF ExtendedCertificateOrCertificate + +ExtendedCertificateOrCertificate ::= CHOICE { + certificate Certificate, -- X.509 + extendedCertificate [0] IMPLICIT ExtendedCertificate -- PKCS#6 +} + +ExtendedCertificate ::= Certificate -- cheating + +Certificates ::= SEQUENCE OF Certificate + +CertificateRevocationLists ::= SET OF CertificateList + +CertificateList ::= SEQUENCE OF Certificate -- This may be defined incorrectly + +CRLSequence ::= SEQUENCE OF CertificateList + +Certificate ::= ANY ({ pkcs7_extract_cert }) -- X.509 + +-- +-- Signer information +-- +SignerInfos ::= CHOICE { + siSet SET OF SignerInfo, + siSequence SEQUENCE OF SignerInfo +} + +SignerInfo ::= SEQUENCE { + version INTEGER ({ pkcs7_note_signerinfo_version }), + sid SignerIdentifier, -- CMS variant, not PKCS#7 + digestAlgorithm DigestAlgorithmIdentifier ({ pkcs7_sig_note_digest_algo }), + authenticatedAttributes CHOICE { + aaSet [0] IMPLICIT SetOfAuthenticatedAttribute + ({ pkcs7_sig_note_set_of_authattrs }), + aaSequence [2] EXPLICIT SEQUENCE OF AuthenticatedAttribute + -- Explicit because easier to compute digest on + -- sequence of attributes and then reuse encoded + -- sequence in aaSequence. + } OPTIONAL, + digestEncryptionAlgorithm + DigestEncryptionAlgorithmIdentifier ({ pkcs7_sig_note_pkey_algo }), + encryptedDigest EncryptedDigest, + unauthenticatedAttributes CHOICE { + uaSet [1] IMPLICIT SET OF UnauthenticatedAttribute, + uaSequence [3] IMPLICIT SEQUENCE OF UnauthenticatedAttribute + } OPTIONAL +} ({ pkcs7_note_signed_info }) + +SignerIdentifier ::= CHOICE { + -- RFC5652 sec 5.3 + issuerAndSerialNumber IssuerAndSerialNumber, + subjectKeyIdentifier [0] IMPLICIT SubjectKeyIdentifier +} + +IssuerAndSerialNumber ::= SEQUENCE { + issuer Name ({ pkcs7_sig_note_issuer }), + serialNumber CertificateSerialNumber ({ pkcs7_sig_note_serial }) +} + +CertificateSerialNumber ::= INTEGER + +SubjectKeyIdentifier ::= OCTET STRING ({ pkcs7_sig_note_skid }) + +SetOfAuthenticatedAttribute ::= SET OF AuthenticatedAttribute + +AuthenticatedAttribute ::= SEQUENCE { + type OBJECT IDENTIFIER ({ pkcs7_note_OID }), + values SET OF ANY ({ pkcs7_sig_note_authenticated_attr }) +} + +UnauthenticatedAttribute ::= SEQUENCE { + type OBJECT IDENTIFIER, + values SET OF ANY +} + +DigestEncryptionAlgorithmIdentifier ::= SEQUENCE { + algorithm OBJECT IDENTIFIER ({ pkcs7_note_OID }), + parameters ANY OPTIONAL +} + +EncryptedDigest ::= OCTET STRING ({ pkcs7_sig_note_signature }) + +--- +--- X.500 Name +--- +Name ::= SEQUENCE OF RelativeDistinguishedName + +RelativeDistinguishedName ::= SET OF AttributeValueAssertion + +AttributeValueAssertion ::= SEQUENCE { + attributeType OBJECT IDENTIFIER ({ pkcs7_note_OID }), + attributeValue ANY +} diff --git a/crypto/asymmetric_keys/pkcs7_key_type.c b/crypto/asymmetric_keys/pkcs7_key_type.c new file mode 100644 index 000000000..b930d3bbf --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_key_type.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Testing module to load key from trusted PKCS#7 message + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKCS7key: "fmt +#include <linux/key.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/verification.h> +#include <linux/key-type.h> +#include <keys/user-type.h> + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("PKCS#7 testing key type"); +MODULE_AUTHOR("Red Hat, Inc."); + +static unsigned pkcs7_usage; +module_param_named(usage, pkcs7_usage, uint, S_IWUSR | S_IRUGO); +MODULE_PARM_DESC(pkcs7_usage, + "Usage to specify when verifying the PKCS#7 message"); + +/* + * Retrieve the PKCS#7 message content. + */ +static int pkcs7_view_content(void *ctx, const void *data, size_t len, + size_t asn1hdrlen) +{ + struct key_preparsed_payload *prep = ctx; + const void *saved_prep_data; + size_t saved_prep_datalen; + int ret; + + saved_prep_data = prep->data; + saved_prep_datalen = prep->datalen; + prep->data = data; + prep->datalen = len; + + ret = user_preparse(prep); + + prep->data = saved_prep_data; + prep->datalen = saved_prep_datalen; + return ret; +} + +/* + * Preparse a PKCS#7 wrapped and validated data blob. + */ +static int pkcs7_preparse(struct key_preparsed_payload *prep) +{ + enum key_being_used_for usage = pkcs7_usage; + + if (usage >= NR__KEY_BEING_USED_FOR) { + pr_err("Invalid usage type %d\n", usage); + return -EINVAL; + } + + return verify_pkcs7_signature(NULL, 0, + prep->data, prep->datalen, + VERIFY_USE_SECONDARY_KEYRING, usage, + pkcs7_view_content, prep); +} + +/* + * user defined keys take an arbitrary string as the description and an + * arbitrary blob of data as the payload + */ +static struct key_type key_type_pkcs7 = { + .name = "pkcs7_test", + .preparse = pkcs7_preparse, + .free_preparse = user_free_preparse, + .instantiate = generic_key_instantiate, + .revoke = user_revoke, + .destroy = user_destroy, + .describe = user_describe, + .read = user_read, +}; + +/* + * Module stuff + */ +static int __init pkcs7_key_init(void) +{ + return register_key_type(&key_type_pkcs7); +} + +static void __exit pkcs7_key_cleanup(void) +{ + unregister_key_type(&key_type_pkcs7); +} + +module_init(pkcs7_key_init); +module_exit(pkcs7_key_cleanup); diff --git a/crypto/asymmetric_keys/pkcs7_parser.c b/crypto/asymmetric_keys/pkcs7_parser.c new file mode 100644 index 000000000..277482bb1 --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_parser.c @@ -0,0 +1,708 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* PKCS#7 parser + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKCS7: "fmt +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/oid_registry.h> +#include <crypto/public_key.h> +#include "pkcs7_parser.h" +#include "pkcs7.asn1.h" + +MODULE_DESCRIPTION("PKCS#7 parser"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + +struct pkcs7_parse_context { + struct pkcs7_message *msg; /* Message being constructed */ + struct pkcs7_signed_info *sinfo; /* SignedInfo being constructed */ + struct pkcs7_signed_info **ppsinfo; + struct x509_certificate *certs; /* Certificate cache */ + struct x509_certificate **ppcerts; + unsigned long data; /* Start of data */ + enum OID last_oid; /* Last OID encountered */ + unsigned x509_index; + unsigned sinfo_index; + const void *raw_serial; + unsigned raw_serial_size; + unsigned raw_issuer_size; + const void *raw_issuer; + const void *raw_skid; + unsigned raw_skid_size; + bool expect_skid; +}; + +/* + * Free a signed information block. + */ +static void pkcs7_free_signed_info(struct pkcs7_signed_info *sinfo) +{ + if (sinfo) { + public_key_signature_free(sinfo->sig); + kfree(sinfo); + } +} + +/** + * pkcs7_free_message - Free a PKCS#7 message + * @pkcs7: The PKCS#7 message to free + */ +void pkcs7_free_message(struct pkcs7_message *pkcs7) +{ + struct x509_certificate *cert; + struct pkcs7_signed_info *sinfo; + + if (pkcs7) { + while (pkcs7->certs) { + cert = pkcs7->certs; + pkcs7->certs = cert->next; + x509_free_certificate(cert); + } + while (pkcs7->crl) { + cert = pkcs7->crl; + pkcs7->crl = cert->next; + x509_free_certificate(cert); + } + while (pkcs7->signed_infos) { + sinfo = pkcs7->signed_infos; + pkcs7->signed_infos = sinfo->next; + pkcs7_free_signed_info(sinfo); + } + kfree(pkcs7); + } +} +EXPORT_SYMBOL_GPL(pkcs7_free_message); + +/* + * Check authenticatedAttributes are provided or not provided consistently. + */ +static int pkcs7_check_authattrs(struct pkcs7_message *msg) +{ + struct pkcs7_signed_info *sinfo; + bool want = false; + + sinfo = msg->signed_infos; + if (!sinfo) + goto inconsistent; + + if (sinfo->authattrs) { + want = true; + msg->have_authattrs = true; + } + + for (sinfo = sinfo->next; sinfo; sinfo = sinfo->next) + if (!!sinfo->authattrs != want) + goto inconsistent; + return 0; + +inconsistent: + pr_warn("Inconsistently supplied authAttrs\n"); + return -EINVAL; +} + +/** + * pkcs7_parse_message - Parse a PKCS#7 message + * @data: The raw binary ASN.1 encoded message to be parsed + * @datalen: The size of the encoded message + */ +struct pkcs7_message *pkcs7_parse_message(const void *data, size_t datalen) +{ + struct pkcs7_parse_context *ctx; + struct pkcs7_message *msg = ERR_PTR(-ENOMEM); + int ret; + + ctx = kzalloc(sizeof(struct pkcs7_parse_context), GFP_KERNEL); + if (!ctx) + goto out_no_ctx; + ctx->msg = kzalloc(sizeof(struct pkcs7_message), GFP_KERNEL); + if (!ctx->msg) + goto out_no_msg; + ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL); + if (!ctx->sinfo) + goto out_no_sinfo; + ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature), + GFP_KERNEL); + if (!ctx->sinfo->sig) + goto out_no_sig; + + ctx->data = (unsigned long)data; + ctx->ppcerts = &ctx->certs; + ctx->ppsinfo = &ctx->msg->signed_infos; + + /* Attempt to decode the signature */ + ret = asn1_ber_decoder(&pkcs7_decoder, ctx, data, datalen); + if (ret < 0) { + msg = ERR_PTR(ret); + goto out; + } + + ret = pkcs7_check_authattrs(ctx->msg); + if (ret < 0) { + msg = ERR_PTR(ret); + goto out; + } + + msg = ctx->msg; + ctx->msg = NULL; + +out: + while (ctx->certs) { + struct x509_certificate *cert = ctx->certs; + ctx->certs = cert->next; + x509_free_certificate(cert); + } +out_no_sig: + pkcs7_free_signed_info(ctx->sinfo); +out_no_sinfo: + pkcs7_free_message(ctx->msg); +out_no_msg: + kfree(ctx); +out_no_ctx: + return msg; +} +EXPORT_SYMBOL_GPL(pkcs7_parse_message); + +/** + * pkcs7_get_content_data - Get access to the PKCS#7 content + * @pkcs7: The preparsed PKCS#7 message to access + * @_data: Place to return a pointer to the data + * @_data_len: Place to return the data length + * @_headerlen: Size of ASN.1 header not included in _data + * + * Get access to the data content of the PKCS#7 message. The size of the + * header of the ASN.1 object that contains it is also provided and can be used + * to adjust *_data and *_data_len to get the entire object. + * + * Returns -ENODATA if the data object was missing from the message. + */ +int pkcs7_get_content_data(const struct pkcs7_message *pkcs7, + const void **_data, size_t *_data_len, + size_t *_headerlen) +{ + if (!pkcs7->data) + return -ENODATA; + + *_data = pkcs7->data; + *_data_len = pkcs7->data_len; + if (_headerlen) + *_headerlen = pkcs7->data_hdrlen; + return 0; +} +EXPORT_SYMBOL_GPL(pkcs7_get_content_data); + +/* + * Note an OID when we find one for later processing when we know how + * to interpret it. + */ +int pkcs7_note_OID(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + ctx->last_oid = look_up_OID(value, vlen); + if (ctx->last_oid == OID__NR) { + char buffer[50]; + sprint_oid(value, vlen, buffer, sizeof(buffer)); + printk("PKCS7: Unknown OID: [%lu] %s\n", + (unsigned long)value - ctx->data, buffer); + } + return 0; +} + +/* + * Note the digest algorithm for the signature. + */ +int pkcs7_sig_note_digest_algo(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + switch (ctx->last_oid) { + case OID_md4: + ctx->sinfo->sig->hash_algo = "md4"; + break; + case OID_md5: + ctx->sinfo->sig->hash_algo = "md5"; + break; + case OID_sha1: + ctx->sinfo->sig->hash_algo = "sha1"; + break; + case OID_sha256: + ctx->sinfo->sig->hash_algo = "sha256"; + break; + case OID_sha384: + ctx->sinfo->sig->hash_algo = "sha384"; + break; + case OID_sha512: + ctx->sinfo->sig->hash_algo = "sha512"; + break; + case OID_sha224: + ctx->sinfo->sig->hash_algo = "sha224"; + break; + case OID_sm3: + ctx->sinfo->sig->hash_algo = "sm3"; + break; + case OID_gost2012Digest256: + ctx->sinfo->sig->hash_algo = "streebog256"; + break; + case OID_gost2012Digest512: + ctx->sinfo->sig->hash_algo = "streebog512"; + break; + default: + printk("Unsupported digest algo: %u\n", ctx->last_oid); + return -ENOPKG; + } + return 0; +} + +/* + * Note the public key algorithm for the signature. + */ +int pkcs7_sig_note_pkey_algo(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + switch (ctx->last_oid) { + case OID_rsaEncryption: + ctx->sinfo->sig->pkey_algo = "rsa"; + ctx->sinfo->sig->encoding = "pkcs1"; + break; + case OID_id_ecdsa_with_sha1: + case OID_id_ecdsa_with_sha224: + case OID_id_ecdsa_with_sha256: + case OID_id_ecdsa_with_sha384: + case OID_id_ecdsa_with_sha512: + ctx->sinfo->sig->pkey_algo = "ecdsa"; + ctx->sinfo->sig->encoding = "x962"; + break; + case OID_SM2_with_SM3: + ctx->sinfo->sig->pkey_algo = "sm2"; + ctx->sinfo->sig->encoding = "raw"; + break; + case OID_gost2012PKey256: + case OID_gost2012PKey512: + ctx->sinfo->sig->pkey_algo = "ecrdsa"; + ctx->sinfo->sig->encoding = "raw"; + break; + default: + printk("Unsupported pkey algo: %u\n", ctx->last_oid); + return -ENOPKG; + } + return 0; +} + +/* + * We only support signed data [RFC2315 sec 9]. + */ +int pkcs7_check_content_type(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + if (ctx->last_oid != OID_signed_data) { + pr_warn("Only support pkcs7_signedData type\n"); + return -EINVAL; + } + + return 0; +} + +/* + * Note the SignedData version + */ +int pkcs7_note_signeddata_version(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + unsigned version; + + if (vlen != 1) + goto unsupported; + + ctx->msg->version = version = *(const u8 *)value; + switch (version) { + case 1: + /* PKCS#7 SignedData [RFC2315 sec 9.1] + * CMS ver 1 SignedData [RFC5652 sec 5.1] + */ + break; + case 3: + /* CMS ver 3 SignedData [RFC2315 sec 5.1] */ + break; + default: + goto unsupported; + } + + return 0; + +unsupported: + pr_warn("Unsupported SignedData version\n"); + return -EINVAL; +} + +/* + * Note the SignerInfo version + */ +int pkcs7_note_signerinfo_version(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + unsigned version; + + if (vlen != 1) + goto unsupported; + + version = *(const u8 *)value; + switch (version) { + case 1: + /* PKCS#7 SignerInfo [RFC2315 sec 9.2] + * CMS ver 1 SignerInfo [RFC5652 sec 5.3] + */ + if (ctx->msg->version != 1) + goto version_mismatch; + ctx->expect_skid = false; + break; + case 3: + /* CMS ver 3 SignerInfo [RFC2315 sec 5.3] */ + if (ctx->msg->version == 1) + goto version_mismatch; + ctx->expect_skid = true; + break; + default: + goto unsupported; + } + + return 0; + +unsupported: + pr_warn("Unsupported SignerInfo version\n"); + return -EINVAL; +version_mismatch: + pr_warn("SignedData-SignerInfo version mismatch\n"); + return -EBADMSG; +} + +/* + * Extract a certificate and store it in the context. + */ +int pkcs7_extract_cert(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + struct x509_certificate *x509; + + if (tag != ((ASN1_UNIV << 6) | ASN1_CONS_BIT | ASN1_SEQ)) { + pr_debug("Cert began with tag %02x at %lu\n", + tag, (unsigned long)ctx - ctx->data); + return -EBADMSG; + } + + /* We have to correct for the header so that the X.509 parser can start + * from the beginning. Note that since X.509 stipulates DER, there + * probably shouldn't be an EOC trailer - but it is in PKCS#7 (which + * stipulates BER). + */ + value -= hdrlen; + vlen += hdrlen; + + if (((u8*)value)[1] == 0x80) + vlen += 2; /* Indefinite length - there should be an EOC */ + + x509 = x509_cert_parse(value, vlen); + if (IS_ERR(x509)) + return PTR_ERR(x509); + + x509->index = ++ctx->x509_index; + pr_debug("Got cert %u for %s\n", x509->index, x509->subject); + pr_debug("- fingerprint %*phN\n", x509->id->len, x509->id->data); + + *ctx->ppcerts = x509; + ctx->ppcerts = &x509->next; + return 0; +} + +/* + * Save the certificate list + */ +int pkcs7_note_certificate_list(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + pr_devel("Got cert list (%02x)\n", tag); + + *ctx->ppcerts = ctx->msg->certs; + ctx->msg->certs = ctx->certs; + ctx->certs = NULL; + ctx->ppcerts = &ctx->certs; + return 0; +} + +/* + * Note the content type. + */ +int pkcs7_note_content(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + if (ctx->last_oid != OID_data && + ctx->last_oid != OID_msIndirectData) { + pr_warn("Unsupported data type %d\n", ctx->last_oid); + return -EINVAL; + } + + ctx->msg->data_type = ctx->last_oid; + return 0; +} + +/* + * Extract the data from the message and store that and its content type OID in + * the context. + */ +int pkcs7_note_data(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + pr_debug("Got data\n"); + + ctx->msg->data = value; + ctx->msg->data_len = vlen; + ctx->msg->data_hdrlen = hdrlen; + return 0; +} + +/* + * Parse authenticated attributes. + */ +int pkcs7_sig_note_authenticated_attr(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + enum OID content_type; + + pr_devel("AuthAttr: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value); + + switch (ctx->last_oid) { + case OID_contentType: + if (__test_and_set_bit(sinfo_has_content_type, &sinfo->aa_set)) + goto repeated; + content_type = look_up_OID(value, vlen); + if (content_type != ctx->msg->data_type) { + pr_warn("Mismatch between global data type (%d) and sinfo %u (%d)\n", + ctx->msg->data_type, sinfo->index, + content_type); + return -EBADMSG; + } + return 0; + + case OID_signingTime: + if (__test_and_set_bit(sinfo_has_signing_time, &sinfo->aa_set)) + goto repeated; + /* Should we check that the signing time is consistent + * with the signer's X.509 cert? + */ + return x509_decode_time(&sinfo->signing_time, + hdrlen, tag, value, vlen); + + case OID_messageDigest: + if (__test_and_set_bit(sinfo_has_message_digest, &sinfo->aa_set)) + goto repeated; + if (tag != ASN1_OTS) + return -EBADMSG; + sinfo->msgdigest = value; + sinfo->msgdigest_len = vlen; + return 0; + + case OID_smimeCapabilites: + if (__test_and_set_bit(sinfo_has_smime_caps, &sinfo->aa_set)) + goto repeated; + if (ctx->msg->data_type != OID_msIndirectData) { + pr_warn("S/MIME Caps only allowed with Authenticode\n"); + return -EKEYREJECTED; + } + return 0; + + /* Microsoft SpOpusInfo seems to be contain cont[0] 16-bit BE + * char URLs and cont[1] 8-bit char URLs. + * + * Microsoft StatementType seems to contain a list of OIDs that + * are also used as extendedKeyUsage types in X.509 certs. + */ + case OID_msSpOpusInfo: + if (__test_and_set_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) + goto repeated; + goto authenticode_check; + case OID_msStatementType: + if (__test_and_set_bit(sinfo_has_ms_statement_type, &sinfo->aa_set)) + goto repeated; + authenticode_check: + if (ctx->msg->data_type != OID_msIndirectData) { + pr_warn("Authenticode AuthAttrs only allowed with Authenticode\n"); + return -EKEYREJECTED; + } + /* I'm not sure how to validate these */ + return 0; + default: + return 0; + } + +repeated: + /* We permit max one item per AuthenticatedAttribute and no repeats */ + pr_warn("Repeated/multivalue AuthAttrs not permitted\n"); + return -EKEYREJECTED; +} + +/* + * Note the set of auth attributes for digestion purposes [RFC2315 sec 9.3] + */ +int pkcs7_sig_note_set_of_authattrs(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + + if (!test_bit(sinfo_has_content_type, &sinfo->aa_set) || + !test_bit(sinfo_has_message_digest, &sinfo->aa_set)) { + pr_warn("Missing required AuthAttr\n"); + return -EBADMSG; + } + + if (ctx->msg->data_type != OID_msIndirectData && + test_bit(sinfo_has_ms_opus_info, &sinfo->aa_set)) { + pr_warn("Unexpected Authenticode AuthAttr\n"); + return -EBADMSG; + } + + /* We need to switch the 'CONT 0' to a 'SET OF' when we digest */ + sinfo->authattrs = value - (hdrlen - 1); + sinfo->authattrs_len = vlen + (hdrlen - 1); + return 0; +} + +/* + * Note the issuing certificate serial number + */ +int pkcs7_sig_note_serial(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + ctx->raw_serial = value; + ctx->raw_serial_size = vlen; + return 0; +} + +/* + * Note the issuer's name + */ +int pkcs7_sig_note_issuer(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + ctx->raw_issuer = value; + ctx->raw_issuer_size = vlen; + return 0; +} + +/* + * Note the issuing cert's subjectKeyIdentifier + */ +int pkcs7_sig_note_skid(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + pr_devel("SKID: %02x %zu [%*ph]\n", tag, vlen, (unsigned)vlen, value); + + ctx->raw_skid = value; + ctx->raw_skid_size = vlen; + return 0; +} + +/* + * Note the signature data + */ +int pkcs7_sig_note_signature(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + + ctx->sinfo->sig->s = kmemdup(value, vlen, GFP_KERNEL); + if (!ctx->sinfo->sig->s) + return -ENOMEM; + + ctx->sinfo->sig->s_size = vlen; + return 0; +} + +/* + * Note a signature information block + */ +int pkcs7_note_signed_info(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs7_parse_context *ctx = context; + struct pkcs7_signed_info *sinfo = ctx->sinfo; + struct asymmetric_key_id *kid; + + if (ctx->msg->data_type == OID_msIndirectData && !sinfo->authattrs) { + pr_warn("Authenticode requires AuthAttrs\n"); + return -EBADMSG; + } + + /* Generate cert issuer + serial number key ID */ + if (!ctx->expect_skid) { + kid = asymmetric_key_generate_id(ctx->raw_serial, + ctx->raw_serial_size, + ctx->raw_issuer, + ctx->raw_issuer_size); + } else { + kid = asymmetric_key_generate_id(ctx->raw_skid, + ctx->raw_skid_size, + "", 0); + } + if (IS_ERR(kid)) + return PTR_ERR(kid); + + pr_devel("SINFO KID: %u [%*phN]\n", kid->len, kid->len, kid->data); + + sinfo->sig->auth_ids[0] = kid; + sinfo->index = ++ctx->sinfo_index; + *ctx->ppsinfo = sinfo; + ctx->ppsinfo = &sinfo->next; + ctx->sinfo = kzalloc(sizeof(struct pkcs7_signed_info), GFP_KERNEL); + if (!ctx->sinfo) + return -ENOMEM; + ctx->sinfo->sig = kzalloc(sizeof(struct public_key_signature), + GFP_KERNEL); + if (!ctx->sinfo->sig) + return -ENOMEM; + return 0; +} diff --git a/crypto/asymmetric_keys/pkcs7_parser.h b/crypto/asymmetric_keys/pkcs7_parser.h new file mode 100644 index 000000000..e17f7ce4f --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_parser.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* PKCS#7 crypto data parser internal definitions + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <linux/oid_registry.h> +#include <crypto/pkcs7.h> +#include "x509_parser.h" + +#define kenter(FMT, ...) \ + pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__) +#define kleave(FMT, ...) \ + pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__) + +struct pkcs7_signed_info { + struct pkcs7_signed_info *next; + struct x509_certificate *signer; /* Signing certificate (in msg->certs) */ + unsigned index; + bool unsupported_crypto; /* T if not usable due to missing crypto */ + bool blacklisted; + + /* Message digest - the digest of the Content Data (or NULL) */ + const void *msgdigest; + unsigned msgdigest_len; + + /* Authenticated Attribute data (or NULL) */ + unsigned authattrs_len; + const void *authattrs; + unsigned long aa_set; +#define sinfo_has_content_type 0 +#define sinfo_has_signing_time 1 +#define sinfo_has_message_digest 2 +#define sinfo_has_smime_caps 3 +#define sinfo_has_ms_opus_info 4 +#define sinfo_has_ms_statement_type 5 + time64_t signing_time; + + /* Message signature. + * + * This contains the generated digest of _either_ the Content Data or + * the Authenticated Attributes [RFC2315 9.3]. If the latter, one of + * the attributes contains the digest of the Content Data within it. + * + * This also contains the issuing cert serial number and issuer's name + * [PKCS#7 or CMS ver 1] or issuing cert's SKID [CMS ver 3]. + */ + struct public_key_signature *sig; +}; + +struct pkcs7_message { + struct x509_certificate *certs; /* Certificate list */ + struct x509_certificate *crl; /* Revocation list */ + struct pkcs7_signed_info *signed_infos; + u8 version; /* Version of cert (1 -> PKCS#7 or CMS; 3 -> CMS) */ + bool have_authattrs; /* T if have authattrs */ + + /* Content Data (or NULL) */ + enum OID data_type; /* Type of Data */ + size_t data_len; /* Length of Data */ + size_t data_hdrlen; /* Length of Data ASN.1 header */ + const void *data; /* Content Data (or 0) */ +}; diff --git a/crypto/asymmetric_keys/pkcs7_trust.c b/crypto/asymmetric_keys/pkcs7_trust.c new file mode 100644 index 000000000..9a87c34ed --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_trust.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Validate the trust chain of a PKCS#7 message. + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKCS7: "fmt +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/asn1.h> +#include <linux/key.h> +#include <keys/asymmetric-type.h> +#include <crypto/public_key.h> +#include "pkcs7_parser.h" + +/* + * Check the trust on one PKCS#7 SignedInfo block. + */ +static int pkcs7_validate_trust_one(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo, + struct key *trust_keyring) +{ + struct public_key_signature *sig = sinfo->sig; + struct x509_certificate *x509, *last = NULL, *p; + struct key *key; + int ret; + + kenter(",%u,", sinfo->index); + + if (sinfo->unsupported_crypto) { + kleave(" = -ENOPKG [cached]"); + return -ENOPKG; + } + + for (x509 = sinfo->signer; x509; x509 = x509->signer) { + if (x509->seen) { + if (x509->verified) + goto verified; + kleave(" = -ENOKEY [cached]"); + return -ENOKEY; + } + x509->seen = true; + + /* Look to see if this certificate is present in the trusted + * keys. + */ + key = find_asymmetric_key(trust_keyring, + x509->id, x509->skid, NULL, false); + if (!IS_ERR(key)) { + /* One of the X.509 certificates in the PKCS#7 message + * is apparently the same as one we already trust. + * Verify that the trusted variant can also validate + * the signature on the descendant. + */ + pr_devel("sinfo %u: Cert %u as key %x\n", + sinfo->index, x509->index, key_serial(key)); + goto matched; + } + if (key == ERR_PTR(-ENOMEM)) + return -ENOMEM; + + /* Self-signed certificates form roots of their own, and if we + * don't know them, then we can't accept them. + */ + if (x509->signer == x509) { + kleave(" = -ENOKEY [unknown self-signed]"); + return -ENOKEY; + } + + might_sleep(); + last = x509; + sig = last->sig; + } + + /* No match - see if the root certificate has a signer amongst the + * trusted keys. + */ + if (last && (last->sig->auth_ids[0] || last->sig->auth_ids[1])) { + key = find_asymmetric_key(trust_keyring, + last->sig->auth_ids[0], + last->sig->auth_ids[1], + NULL, false); + if (!IS_ERR(key)) { + x509 = last; + pr_devel("sinfo %u: Root cert %u signer is key %x\n", + sinfo->index, x509->index, key_serial(key)); + goto matched; + } + if (PTR_ERR(key) != -ENOKEY) + return PTR_ERR(key); + } + + /* As a last resort, see if we have a trusted public key that matches + * the signed info directly. + */ + key = find_asymmetric_key(trust_keyring, + sinfo->sig->auth_ids[0], NULL, NULL, false); + if (!IS_ERR(key)) { + pr_devel("sinfo %u: Direct signer is key %x\n", + sinfo->index, key_serial(key)); + x509 = NULL; + sig = sinfo->sig; + goto matched; + } + if (PTR_ERR(key) != -ENOKEY) + return PTR_ERR(key); + + kleave(" = -ENOKEY [no backref]"); + return -ENOKEY; + +matched: + ret = verify_signature(key, sig); + key_put(key); + if (ret < 0) { + if (ret == -ENOMEM) + return ret; + kleave(" = -EKEYREJECTED [verify %d]", ret); + return -EKEYREJECTED; + } + +verified: + if (x509) { + x509->verified = true; + for (p = sinfo->signer; p != x509; p = p->signer) + p->verified = true; + } + kleave(" = 0"); + return 0; +} + +/** + * pkcs7_validate_trust - Validate PKCS#7 trust chain + * @pkcs7: The PKCS#7 certificate to validate + * @trust_keyring: Signing certificates to use as starting points + * + * Validate that the certificate chain inside the PKCS#7 message intersects + * keys we already know and trust. + * + * Returns, in order of descending priority: + * + * (*) -EKEYREJECTED if a signature failed to match for which we have a valid + * key, or: + * + * (*) 0 if at least one signature chain intersects with the keys in the trust + * keyring, or: + * + * (*) -ENOPKG if a suitable crypto module couldn't be found for a check on a + * chain. + * + * (*) -ENOKEY if we couldn't find a match for any of the signature chains in + * the message. + * + * May also return -ENOMEM. + */ +int pkcs7_validate_trust(struct pkcs7_message *pkcs7, + struct key *trust_keyring) +{ + struct pkcs7_signed_info *sinfo; + struct x509_certificate *p; + int cached_ret = -ENOKEY; + int ret; + + for (p = pkcs7->certs; p; p = p->next) + p->seen = false; + + for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) { + ret = pkcs7_validate_trust_one(pkcs7, sinfo, trust_keyring); + switch (ret) { + case -ENOKEY: + continue; + case -ENOPKG: + if (cached_ret == -ENOKEY) + cached_ret = -ENOPKG; + continue; + case 0: + cached_ret = 0; + continue; + default: + return ret; + } + } + + return cached_ret; +} +EXPORT_SYMBOL_GPL(pkcs7_validate_trust); diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c new file mode 100644 index 000000000..f0d4ff3c2 --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_verify.c @@ -0,0 +1,488 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Verify the signature on a PKCS#7 message. + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKCS7: "fmt +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/asn1.h> +#include <crypto/hash.h> +#include <crypto/hash_info.h> +#include <crypto/public_key.h> +#include "pkcs7_parser.h" + +/* + * Digest the relevant parts of the PKCS#7 data + */ +static int pkcs7_digest(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo) +{ + struct public_key_signature *sig = sinfo->sig; + struct crypto_shash *tfm; + struct shash_desc *desc; + size_t desc_size; + int ret; + + kenter(",%u,%s", sinfo->index, sinfo->sig->hash_algo); + + /* The digest was calculated already. */ + if (sig->digest) + return 0; + + if (!sinfo->sig->hash_algo) + return -ENOPKG; + + /* Allocate the hashing algorithm we're going to need and find out how + * big the hash operational data will be. + */ + tfm = crypto_alloc_shash(sinfo->sig->hash_algo, 0, 0); + if (IS_ERR(tfm)) + return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm); + + desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); + sig->digest_size = crypto_shash_digestsize(tfm); + + ret = -ENOMEM; + sig->digest = kmalloc(sig->digest_size, GFP_KERNEL); + if (!sig->digest) + goto error_no_desc; + + desc = kzalloc(desc_size, GFP_KERNEL); + if (!desc) + goto error_no_desc; + + desc->tfm = tfm; + + /* Digest the message [RFC2315 9.3] */ + ret = crypto_shash_digest(desc, pkcs7->data, pkcs7->data_len, + sig->digest); + if (ret < 0) + goto error; + pr_devel("MsgDigest = [%*ph]\n", 8, sig->digest); + + /* However, if there are authenticated attributes, there must be a + * message digest attribute amongst them which corresponds to the + * digest we just calculated. + */ + if (sinfo->authattrs) { + u8 tag; + + if (!sinfo->msgdigest) { + pr_warn("Sig %u: No messageDigest\n", sinfo->index); + ret = -EKEYREJECTED; + goto error; + } + + if (sinfo->msgdigest_len != sig->digest_size) { + pr_warn("Sig %u: Invalid digest size (%u)\n", + sinfo->index, sinfo->msgdigest_len); + ret = -EBADMSG; + goto error; + } + + if (memcmp(sig->digest, sinfo->msgdigest, + sinfo->msgdigest_len) != 0) { + pr_warn("Sig %u: Message digest doesn't match\n", + sinfo->index); + ret = -EKEYREJECTED; + goto error; + } + + /* We then calculate anew, using the authenticated attributes + * as the contents of the digest instead. Note that we need to + * convert the attributes from a CONT.0 into a SET before we + * hash it. + */ + memset(sig->digest, 0, sig->digest_size); + + ret = crypto_shash_init(desc); + if (ret < 0) + goto error; + tag = ASN1_CONS_BIT | ASN1_SET; + ret = crypto_shash_update(desc, &tag, 1); + if (ret < 0) + goto error; + ret = crypto_shash_finup(desc, sinfo->authattrs, + sinfo->authattrs_len, sig->digest); + if (ret < 0) + goto error; + pr_devel("AADigest = [%*ph]\n", 8, sig->digest); + } + +error: + kfree(desc); +error_no_desc: + crypto_free_shash(tfm); + kleave(" = %d", ret); + return ret; +} + +int pkcs7_get_digest(struct pkcs7_message *pkcs7, const u8 **buf, u32 *len, + enum hash_algo *hash_algo) +{ + struct pkcs7_signed_info *sinfo = pkcs7->signed_infos; + int i, ret; + + /* + * This function doesn't support messages with more than one signature. + */ + if (sinfo == NULL || sinfo->next != NULL) + return -EBADMSG; + + ret = pkcs7_digest(pkcs7, sinfo); + if (ret) + return ret; + + *buf = sinfo->sig->digest; + *len = sinfo->sig->digest_size; + + i = match_string(hash_algo_name, HASH_ALGO__LAST, + sinfo->sig->hash_algo); + if (i >= 0) + *hash_algo = i; + + return 0; +} + +/* + * Find the key (X.509 certificate) to use to verify a PKCS#7 message. PKCS#7 + * uses the issuer's name and the issuing certificate serial number for + * matching purposes. These must match the certificate issuer's name (not + * subject's name) and the certificate serial number [RFC 2315 6.7]. + */ +static int pkcs7_find_key(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo) +{ + struct x509_certificate *x509; + unsigned certix = 1; + + kenter("%u", sinfo->index); + + for (x509 = pkcs7->certs; x509; x509 = x509->next, certix++) { + /* I'm _assuming_ that the generator of the PKCS#7 message will + * encode the fields from the X.509 cert in the same way in the + * PKCS#7 message - but I can't be 100% sure of that. It's + * possible this will need element-by-element comparison. + */ + if (!asymmetric_key_id_same(x509->id, sinfo->sig->auth_ids[0])) + continue; + pr_devel("Sig %u: Found cert serial match X.509[%u]\n", + sinfo->index, certix); + + sinfo->signer = x509; + return 0; + } + + /* The relevant X.509 cert isn't found here, but it might be found in + * the trust keyring. + */ + pr_debug("Sig %u: Issuing X.509 cert not found (#%*phN)\n", + sinfo->index, + sinfo->sig->auth_ids[0]->len, sinfo->sig->auth_ids[0]->data); + return 0; +} + +/* + * Verify the internal certificate chain as best we can. + */ +static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo) +{ + struct public_key_signature *sig; + struct x509_certificate *x509 = sinfo->signer, *p; + struct asymmetric_key_id *auth; + int ret; + + kenter(""); + + for (p = pkcs7->certs; p; p = p->next) + p->seen = false; + + for (;;) { + pr_debug("verify %s: %*phN\n", + x509->subject, + x509->raw_serial_size, x509->raw_serial); + x509->seen = true; + + if (x509->blacklisted) { + /* If this cert is blacklisted, then mark everything + * that depends on this as blacklisted too. + */ + sinfo->blacklisted = true; + for (p = sinfo->signer; p != x509; p = p->signer) + p->blacklisted = true; + pr_debug("- blacklisted\n"); + return 0; + } + + pr_debug("- issuer %s\n", x509->issuer); + sig = x509->sig; + if (sig->auth_ids[0]) + pr_debug("- authkeyid.id %*phN\n", + sig->auth_ids[0]->len, sig->auth_ids[0]->data); + if (sig->auth_ids[1]) + pr_debug("- authkeyid.skid %*phN\n", + sig->auth_ids[1]->len, sig->auth_ids[1]->data); + + if (x509->self_signed) { + /* If there's no authority certificate specified, then + * the certificate must be self-signed and is the root + * of the chain. Likewise if the cert is its own + * authority. + */ + if (x509->unsupported_sig) + goto unsupported_sig_in_x509; + x509->signer = x509; + pr_debug("- self-signed\n"); + return 0; + } + + /* Look through the X.509 certificates in the PKCS#7 message's + * list to see if the next one is there. + */ + auth = sig->auth_ids[0]; + if (auth) { + pr_debug("- want %*phN\n", auth->len, auth->data); + for (p = pkcs7->certs; p; p = p->next) { + pr_debug("- cmp [%u] %*phN\n", + p->index, p->id->len, p->id->data); + if (asymmetric_key_id_same(p->id, auth)) + goto found_issuer_check_skid; + } + } else if (sig->auth_ids[1]) { + auth = sig->auth_ids[1]; + pr_debug("- want %*phN\n", auth->len, auth->data); + for (p = pkcs7->certs; p; p = p->next) { + if (!p->skid) + continue; + pr_debug("- cmp [%u] %*phN\n", + p->index, p->skid->len, p->skid->data); + if (asymmetric_key_id_same(p->skid, auth)) + goto found_issuer; + } + } + + /* We didn't find the root of this chain */ + pr_debug("- top\n"); + return 0; + + found_issuer_check_skid: + /* We matched issuer + serialNumber, but if there's an + * authKeyId.keyId, that must match the CA subjKeyId also. + */ + if (sig->auth_ids[1] && + !asymmetric_key_id_same(p->skid, sig->auth_ids[1])) { + pr_warn("Sig %u: X.509 chain contains auth-skid nonmatch (%u->%u)\n", + sinfo->index, x509->index, p->index); + return -EKEYREJECTED; + } + found_issuer: + pr_debug("- subject %s\n", p->subject); + if (p->seen) { + pr_warn("Sig %u: X.509 chain contains loop\n", + sinfo->index); + return 0; + } + ret = public_key_verify_signature(p->pub, x509->sig); + if (ret < 0) + return ret; + x509->signer = p; + if (x509 == p) { + pr_debug("- self-signed\n"); + return 0; + } + x509 = p; + might_sleep(); + } + +unsupported_sig_in_x509: + /* Just prune the certificate chain at this point if we lack some + * crypto module to go further. Note, however, we don't want to set + * sinfo->unsupported_crypto as the signed info block may still be + * validatable against an X.509 cert lower in the chain that we have a + * trusted copy of. + */ + return 0; +} + +/* + * Verify one signed information block from a PKCS#7 message. + */ +static int pkcs7_verify_one(struct pkcs7_message *pkcs7, + struct pkcs7_signed_info *sinfo) +{ + int ret; + + kenter(",%u", sinfo->index); + + /* First of all, digest the data in the PKCS#7 message and the + * signed information block + */ + ret = pkcs7_digest(pkcs7, sinfo); + if (ret < 0) + return ret; + + /* Find the key for the signature if there is one */ + ret = pkcs7_find_key(pkcs7, sinfo); + if (ret < 0) + return ret; + + if (!sinfo->signer) + return 0; + + pr_devel("Using X.509[%u] for sig %u\n", + sinfo->signer->index, sinfo->index); + + /* Check that the PKCS#7 signing time is valid according to the X.509 + * certificate. We can't, however, check against the system clock + * since that may not have been set yet and may be wrong. + */ + if (test_bit(sinfo_has_signing_time, &sinfo->aa_set)) { + if (sinfo->signing_time < sinfo->signer->valid_from || + sinfo->signing_time > sinfo->signer->valid_to) { + pr_warn("Message signed outside of X.509 validity window\n"); + return -EKEYREJECTED; + } + } + + /* Verify the PKCS#7 binary against the key */ + ret = public_key_verify_signature(sinfo->signer->pub, sinfo->sig); + if (ret < 0) + return ret; + + pr_devel("Verified signature %u\n", sinfo->index); + + /* Verify the internal certificate chain */ + return pkcs7_verify_sig_chain(pkcs7, sinfo); +} + +/** + * pkcs7_verify - Verify a PKCS#7 message + * @pkcs7: The PKCS#7 message to be verified + * @usage: The use to which the key is being put + * + * Verify a PKCS#7 message is internally consistent - that is, the data digest + * matches the digest in the AuthAttrs and any signature in the message or one + * of the X.509 certificates it carries that matches another X.509 cert in the + * message can be verified. + * + * This does not look to match the contents of the PKCS#7 message against any + * external public keys. + * + * Returns, in order of descending priority: + * + * (*) -EKEYREJECTED if a key was selected that had a usage restriction at + * odds with the specified usage, or: + * + * (*) -EKEYREJECTED if a signature failed to match for which we found an + * appropriate X.509 certificate, or: + * + * (*) -EBADMSG if some part of the message was invalid, or: + * + * (*) 0 if a signature chain passed verification, or: + * + * (*) -EKEYREJECTED if a blacklisted key was encountered, or: + * + * (*) -ENOPKG if none of the signature chains are verifiable because suitable + * crypto modules couldn't be found. + */ +int pkcs7_verify(struct pkcs7_message *pkcs7, + enum key_being_used_for usage) +{ + struct pkcs7_signed_info *sinfo; + int actual_ret = -ENOPKG; + int ret; + + kenter(""); + + switch (usage) { + case VERIFYING_MODULE_SIGNATURE: + if (pkcs7->data_type != OID_data) { + pr_warn("Invalid module sig (not pkcs7-data)\n"); + return -EKEYREJECTED; + } + if (pkcs7->have_authattrs) { + pr_warn("Invalid module sig (has authattrs)\n"); + return -EKEYREJECTED; + } + break; + case VERIFYING_FIRMWARE_SIGNATURE: + if (pkcs7->data_type != OID_data) { + pr_warn("Invalid firmware sig (not pkcs7-data)\n"); + return -EKEYREJECTED; + } + if (!pkcs7->have_authattrs) { + pr_warn("Invalid firmware sig (missing authattrs)\n"); + return -EKEYREJECTED; + } + break; + case VERIFYING_KEXEC_PE_SIGNATURE: + if (pkcs7->data_type != OID_msIndirectData) { + pr_warn("Invalid kexec sig (not Authenticode)\n"); + return -EKEYREJECTED; + } + /* Authattr presence checked in parser */ + break; + case VERIFYING_UNSPECIFIED_SIGNATURE: + if (pkcs7->data_type != OID_data) { + pr_warn("Invalid unspecified sig (not pkcs7-data)\n"); + return -EKEYREJECTED; + } + break; + default: + return -EINVAL; + } + + for (sinfo = pkcs7->signed_infos; sinfo; sinfo = sinfo->next) { + ret = pkcs7_verify_one(pkcs7, sinfo); + if (sinfo->blacklisted) { + if (actual_ret == -ENOPKG) + actual_ret = -EKEYREJECTED; + continue; + } + if (ret < 0) { + if (ret == -ENOPKG) { + sinfo->unsupported_crypto = true; + continue; + } + kleave(" = %d", ret); + return ret; + } + actual_ret = 0; + } + + kleave(" = %d", actual_ret); + return actual_ret; +} +EXPORT_SYMBOL_GPL(pkcs7_verify); + +/** + * pkcs7_supply_detached_data - Supply the data needed to verify a PKCS#7 message + * @pkcs7: The PKCS#7 message + * @data: The data to be verified + * @datalen: The amount of data + * + * Supply the detached data needed to verify a PKCS#7 message. Note that no + * attempt to retain/pin the data is made. That is left to the caller. The + * data will not be modified by pkcs7_verify() and will not be freed when the + * PKCS#7 message is freed. + * + * Returns -EINVAL if data is already supplied in the message, 0 otherwise. + */ +int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7, + const void *data, size_t datalen) +{ + if (pkcs7->data) { + pr_warn("Data already supplied\n"); + return -EINVAL; + } + pkcs7->data = data; + pkcs7->data_len = datalen; + return 0; +} +EXPORT_SYMBOL_GPL(pkcs7_supply_detached_data); diff --git a/crypto/asymmetric_keys/pkcs8.asn1 b/crypto/asymmetric_keys/pkcs8.asn1 new file mode 100644 index 000000000..702c41a3c --- /dev/null +++ b/crypto/asymmetric_keys/pkcs8.asn1 @@ -0,0 +1,24 @@ +-- +-- This is the unencrypted variant +-- +PrivateKeyInfo ::= SEQUENCE { + version Version, + privateKeyAlgorithm PrivateKeyAlgorithmIdentifier, + privateKey PrivateKey, + attributes [0] IMPLICIT Attributes OPTIONAL +} + +Version ::= INTEGER ({ pkcs8_note_version }) + +PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier ({ pkcs8_note_algo }) + +PrivateKey ::= OCTET STRING ({ pkcs8_note_key }) + +Attributes ::= SET OF Attribute + +Attribute ::= ANY + +AlgorithmIdentifier ::= SEQUENCE { + algorithm OBJECT IDENTIFIER ({ pkcs8_note_OID }), + parameters ANY OPTIONAL +} diff --git a/crypto/asymmetric_keys/pkcs8_parser.c b/crypto/asymmetric_keys/pkcs8_parser.c new file mode 100644 index 000000000..105dcce27 --- /dev/null +++ b/crypto/asymmetric_keys/pkcs8_parser.c @@ -0,0 +1,180 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* PKCS#8 Private Key parser [RFC 5208]. + * + * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKCS8: "fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/oid_registry.h> +#include <keys/asymmetric-subtype.h> +#include <keys/asymmetric-parser.h> +#include <crypto/public_key.h> +#include "pkcs8.asn1.h" + +struct pkcs8_parse_context { + struct public_key *pub; + unsigned long data; /* Start of data */ + enum OID last_oid; /* Last OID encountered */ + enum OID algo_oid; /* Algorithm OID */ + u32 key_size; + const void *key; +}; + +/* + * Note an OID when we find one for later processing when we know how to + * interpret it. + */ +int pkcs8_note_OID(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs8_parse_context *ctx = context; + + ctx->last_oid = look_up_OID(value, vlen); + if (ctx->last_oid == OID__NR) { + char buffer[50]; + + sprint_oid(value, vlen, buffer, sizeof(buffer)); + pr_info("Unknown OID: [%lu] %s\n", + (unsigned long)value - ctx->data, buffer); + } + return 0; +} + +/* + * Note the version number of the ASN.1 blob. + */ +int pkcs8_note_version(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + if (vlen != 1 || ((const u8 *)value)[0] != 0) { + pr_warn("Unsupported PKCS#8 version\n"); + return -EBADMSG; + } + return 0; +} + +/* + * Note the public algorithm. + */ +int pkcs8_note_algo(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs8_parse_context *ctx = context; + + if (ctx->last_oid != OID_rsaEncryption) + return -ENOPKG; + + ctx->pub->pkey_algo = "rsa"; + return 0; +} + +/* + * Note the key data of the ASN.1 blob. + */ +int pkcs8_note_key(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct pkcs8_parse_context *ctx = context; + + ctx->key = value; + ctx->key_size = vlen; + return 0; +} + +/* + * Parse a PKCS#8 private key blob. + */ +static struct public_key *pkcs8_parse(const void *data, size_t datalen) +{ + struct pkcs8_parse_context ctx; + struct public_key *pub; + long ret; + + memset(&ctx, 0, sizeof(ctx)); + + ret = -ENOMEM; + ctx.pub = kzalloc(sizeof(struct public_key), GFP_KERNEL); + if (!ctx.pub) + goto error; + + ctx.data = (unsigned long)data; + + /* Attempt to decode the private key */ + ret = asn1_ber_decoder(&pkcs8_decoder, &ctx, data, datalen); + if (ret < 0) + goto error_decode; + + ret = -ENOMEM; + pub = ctx.pub; + pub->key = kmemdup(ctx.key, ctx.key_size, GFP_KERNEL); + if (!pub->key) + goto error_decode; + + pub->keylen = ctx.key_size; + pub->key_is_private = true; + return pub; + +error_decode: + kfree(ctx.pub); +error: + return ERR_PTR(ret); +} + +/* + * Attempt to parse a data blob for a key as a PKCS#8 private key. + */ +static int pkcs8_key_preparse(struct key_preparsed_payload *prep) +{ + struct public_key *pub; + + pub = pkcs8_parse(prep->data, prep->datalen); + if (IS_ERR(pub)) + return PTR_ERR(pub); + + pr_devel("Cert Key Algo: %s\n", pub->pkey_algo); + pub->id_type = "PKCS8"; + + /* We're pinning the module by being linked against it */ + __module_get(public_key_subtype.owner); + prep->payload.data[asym_subtype] = &public_key_subtype; + prep->payload.data[asym_key_ids] = NULL; + prep->payload.data[asym_crypto] = pub; + prep->payload.data[asym_auth] = NULL; + prep->quotalen = 100; + return 0; +} + +static struct asymmetric_key_parser pkcs8_key_parser = { + .owner = THIS_MODULE, + .name = "pkcs8", + .parse = pkcs8_key_preparse, +}; + +/* + * Module stuff + */ +static int __init pkcs8_key_init(void) +{ + return register_asymmetric_key_parser(&pkcs8_key_parser); +} + +static void __exit pkcs8_key_exit(void) +{ + unregister_asymmetric_key_parser(&pkcs8_key_parser); +} + +module_init(pkcs8_key_init); +module_exit(pkcs8_key_exit); + +MODULE_DESCRIPTION("PKCS#8 certificate parser"); +MODULE_LICENSE("GPL"); diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c new file mode 100644 index 000000000..1dcab2798 --- /dev/null +++ b/crypto/asymmetric_keys/public_key.c @@ -0,0 +1,473 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* In-software asymmetric public-key crypto subtype + * + * See Documentation/crypto/asymmetric-keys.rst + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PKEY: "fmt +#include <crypto/akcipher.h> +#include <crypto/public_key.h> +#include <crypto/sig.h> +#include <keys/asymmetric-subtype.h> +#include <linux/asn1.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/string.h> + +MODULE_DESCRIPTION("In-software asymmetric public-key subtype"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); + +/* + * Provide a part of a description of the key for /proc/keys. + */ +static void public_key_describe(const struct key *asymmetric_key, + struct seq_file *m) +{ + struct public_key *key = asymmetric_key->payload.data[asym_crypto]; + + if (key) + seq_printf(m, "%s.%s", key->id_type, key->pkey_algo); +} + +/* + * Destroy a public key algorithm key. + */ +void public_key_free(struct public_key *key) +{ + if (key) { + kfree_sensitive(key->key); + kfree(key->params); + kfree(key); + } +} +EXPORT_SYMBOL_GPL(public_key_free); + +/* + * Destroy a public key algorithm key. + */ +static void public_key_destroy(void *payload0, void *payload3) +{ + public_key_free(payload0); + public_key_signature_free(payload3); +} + +/* + * Given a public_key, and an encoding and hash_algo to be used for signing + * and/or verification with that key, determine the name of the corresponding + * akcipher algorithm. Also check that encoding and hash_algo are allowed. + */ +static int +software_key_determine_akcipher(const struct public_key *pkey, + const char *encoding, const char *hash_algo, + char alg_name[CRYPTO_MAX_ALG_NAME], bool *sig, + enum kernel_pkey_operation op) +{ + int n; + + *sig = true; + + if (!encoding) + return -EINVAL; + + if (strcmp(pkey->pkey_algo, "rsa") == 0) { + /* + * RSA signatures usually use EMSA-PKCS1-1_5 [RFC3447 sec 8.2]. + */ + if (strcmp(encoding, "pkcs1") == 0) { + *sig = op == kernel_pkey_sign || + op == kernel_pkey_verify; + if (!hash_algo) { + n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME, + "pkcs1pad(%s)", + pkey->pkey_algo); + } else { + n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME, + "pkcs1pad(%s,%s)", + pkey->pkey_algo, hash_algo); + } + return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0; + } + if (strcmp(encoding, "raw") != 0) + return -EINVAL; + /* + * Raw RSA cannot differentiate between different hash + * algorithms. + */ + if (hash_algo) + return -EINVAL; + *sig = false; + } else if (strncmp(pkey->pkey_algo, "ecdsa", 5) == 0) { + if (strcmp(encoding, "x962") != 0) + return -EINVAL; + /* + * ECDSA signatures are taken over a raw hash, so they don't + * differentiate between different hash algorithms. That means + * that the verifier should hard-code a specific hash algorithm. + * Unfortunately, in practice ECDSA is used with multiple SHAs, + * so we have to allow all of them and not just one. + */ + if (!hash_algo) + return -EINVAL; + if (strcmp(hash_algo, "sha1") != 0 && + strcmp(hash_algo, "sha224") != 0 && + strcmp(hash_algo, "sha256") != 0 && + strcmp(hash_algo, "sha384") != 0 && + strcmp(hash_algo, "sha512") != 0) + return -EINVAL; + } else if (strcmp(pkey->pkey_algo, "sm2") == 0) { + if (strcmp(encoding, "raw") != 0) + return -EINVAL; + if (!hash_algo) + return -EINVAL; + if (strcmp(hash_algo, "sm3") != 0) + return -EINVAL; + } else if (strcmp(pkey->pkey_algo, "ecrdsa") == 0) { + if (strcmp(encoding, "raw") != 0) + return -EINVAL; + if (!hash_algo) + return -EINVAL; + if (strcmp(hash_algo, "streebog256") != 0 && + strcmp(hash_algo, "streebog512") != 0) + return -EINVAL; + } else { + /* Unknown public key algorithm */ + return -ENOPKG; + } + if (strscpy(alg_name, pkey->pkey_algo, CRYPTO_MAX_ALG_NAME) < 0) + return -EINVAL; + return 0; +} + +static u8 *pkey_pack_u32(u8 *dst, u32 val) +{ + memcpy(dst, &val, sizeof(val)); + return dst + sizeof(val); +} + +/* + * Query information about a key. + */ +static int software_key_query(const struct kernel_pkey_params *params, + struct kernel_pkey_query *info) +{ + struct crypto_akcipher *tfm; + struct public_key *pkey = params->key->payload.data[asym_crypto]; + char alg_name[CRYPTO_MAX_ALG_NAME]; + struct crypto_sig *sig; + u8 *key, *ptr; + int ret, len; + bool issig; + + ret = software_key_determine_akcipher(pkey, params->encoding, + params->hash_algo, alg_name, + &issig, kernel_pkey_sign); + if (ret < 0) + return ret; + + key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen, + GFP_KERNEL); + if (!key) + return -ENOMEM; + + memcpy(key, pkey->key, pkey->keylen); + ptr = key + pkey->keylen; + ptr = pkey_pack_u32(ptr, pkey->algo); + ptr = pkey_pack_u32(ptr, pkey->paramlen); + memcpy(ptr, pkey->params, pkey->paramlen); + + if (issig) { + sig = crypto_alloc_sig(alg_name, 0, 0); + if (IS_ERR(sig)) { + ret = PTR_ERR(sig); + goto error_free_key; + } + + if (pkey->key_is_private) + ret = crypto_sig_set_privkey(sig, key, pkey->keylen); + else + ret = crypto_sig_set_pubkey(sig, key, pkey->keylen); + if (ret < 0) + goto error_free_tfm; + + len = crypto_sig_maxsize(sig); + + info->supported_ops = KEYCTL_SUPPORTS_VERIFY; + if (pkey->key_is_private) + info->supported_ops |= KEYCTL_SUPPORTS_SIGN; + + if (strcmp(params->encoding, "pkcs1") == 0) { + info->supported_ops |= KEYCTL_SUPPORTS_ENCRYPT; + if (pkey->key_is_private) + info->supported_ops |= KEYCTL_SUPPORTS_DECRYPT; + } + } else { + tfm = crypto_alloc_akcipher(alg_name, 0, 0); + if (IS_ERR(tfm)) { + ret = PTR_ERR(tfm); + goto error_free_key; + } + + if (pkey->key_is_private) + ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen); + else + ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen); + if (ret < 0) + goto error_free_tfm; + + len = crypto_akcipher_maxsize(tfm); + + info->supported_ops = KEYCTL_SUPPORTS_ENCRYPT; + if (pkey->key_is_private) + info->supported_ops |= KEYCTL_SUPPORTS_DECRYPT; + } + + info->key_size = len * 8; + + if (strncmp(pkey->pkey_algo, "ecdsa", 5) == 0) { + /* + * ECDSA key sizes are much smaller than RSA, and thus could + * operate on (hashed) inputs that are larger than key size. + * For example SHA384-hashed input used with secp256r1 + * based keys. Set max_data_size to be at least as large as + * the largest supported hash size (SHA512) + */ + info->max_data_size = 64; + + /* + * Verify takes ECDSA-Sig (described in RFC 5480) as input, + * which is actually 2 'key_size'-bit integers encoded in + * ASN.1. Account for the ASN.1 encoding overhead here. + */ + info->max_sig_size = 2 * (len + 3) + 2; + } else { + info->max_data_size = len; + info->max_sig_size = len; + } + + info->max_enc_size = len; + info->max_dec_size = len; + + ret = 0; + +error_free_tfm: + if (issig) + crypto_free_sig(sig); + else + crypto_free_akcipher(tfm); +error_free_key: + kfree_sensitive(key); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} + +/* + * Do encryption, decryption and signing ops. + */ +static int software_key_eds_op(struct kernel_pkey_params *params, + const void *in, void *out) +{ + const struct public_key *pkey = params->key->payload.data[asym_crypto]; + char alg_name[CRYPTO_MAX_ALG_NAME]; + struct crypto_akcipher *tfm; + struct crypto_sig *sig; + char *key, *ptr; + bool issig; + int ksz; + int ret; + + pr_devel("==>%s()\n", __func__); + + ret = software_key_determine_akcipher(pkey, params->encoding, + params->hash_algo, alg_name, + &issig, params->op); + if (ret < 0) + return ret; + + key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen, + GFP_KERNEL); + if (!key) + return -ENOMEM; + + memcpy(key, pkey->key, pkey->keylen); + ptr = key + pkey->keylen; + ptr = pkey_pack_u32(ptr, pkey->algo); + ptr = pkey_pack_u32(ptr, pkey->paramlen); + memcpy(ptr, pkey->params, pkey->paramlen); + + if (issig) { + sig = crypto_alloc_sig(alg_name, 0, 0); + if (IS_ERR(sig)) { + ret = PTR_ERR(sig); + goto error_free_key; + } + + if (pkey->key_is_private) + ret = crypto_sig_set_privkey(sig, key, pkey->keylen); + else + ret = crypto_sig_set_pubkey(sig, key, pkey->keylen); + if (ret) + goto error_free_tfm; + + ksz = crypto_sig_maxsize(sig); + } else { + tfm = crypto_alloc_akcipher(alg_name, 0, 0); + if (IS_ERR(tfm)) { + ret = PTR_ERR(tfm); + goto error_free_key; + } + + if (pkey->key_is_private) + ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen); + else + ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen); + if (ret) + goto error_free_tfm; + + ksz = crypto_akcipher_maxsize(tfm); + } + + ret = -EINVAL; + + /* Perform the encryption calculation. */ + switch (params->op) { + case kernel_pkey_encrypt: + if (issig) + break; + ret = crypto_akcipher_sync_encrypt(tfm, in, params->in_len, + out, params->out_len); + break; + case kernel_pkey_decrypt: + if (issig) + break; + ret = crypto_akcipher_sync_decrypt(tfm, in, params->in_len, + out, params->out_len); + break; + case kernel_pkey_sign: + if (!issig) + break; + ret = crypto_sig_sign(sig, in, params->in_len, + out, params->out_len); + break; + default: + BUG(); + } + + if (ret == 0) + ret = ksz; + +error_free_tfm: + if (issig) + crypto_free_sig(sig); + else + crypto_free_akcipher(tfm); +error_free_key: + kfree_sensitive(key); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} + +/* + * Verify a signature using a public key. + */ +int public_key_verify_signature(const struct public_key *pkey, + const struct public_key_signature *sig) +{ + char alg_name[CRYPTO_MAX_ALG_NAME]; + struct crypto_sig *tfm; + char *key, *ptr; + bool issig; + int ret; + + pr_devel("==>%s()\n", __func__); + + BUG_ON(!pkey); + BUG_ON(!sig); + BUG_ON(!sig->s); + + /* + * If the signature specifies a public key algorithm, it *must* match + * the key's actual public key algorithm. + * + * Small exception: ECDSA signatures don't specify the curve, but ECDSA + * keys do. So the strings can mismatch slightly in that case: + * "ecdsa-nist-*" for the key, but "ecdsa" for the signature. + */ + if (sig->pkey_algo) { + if (strcmp(pkey->pkey_algo, sig->pkey_algo) != 0 && + (strncmp(pkey->pkey_algo, "ecdsa-", 6) != 0 || + strcmp(sig->pkey_algo, "ecdsa") != 0)) + return -EKEYREJECTED; + } + + ret = software_key_determine_akcipher(pkey, sig->encoding, + sig->hash_algo, alg_name, + &issig, kernel_pkey_verify); + if (ret < 0) + return ret; + + tfm = crypto_alloc_sig(alg_name, 0, 0); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); + + key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen, + GFP_KERNEL); + if (!key) { + ret = -ENOMEM; + goto error_free_tfm; + } + + memcpy(key, pkey->key, pkey->keylen); + ptr = key + pkey->keylen; + ptr = pkey_pack_u32(ptr, pkey->algo); + ptr = pkey_pack_u32(ptr, pkey->paramlen); + memcpy(ptr, pkey->params, pkey->paramlen); + + if (pkey->key_is_private) + ret = crypto_sig_set_privkey(tfm, key, pkey->keylen); + else + ret = crypto_sig_set_pubkey(tfm, key, pkey->keylen); + if (ret) + goto error_free_key; + + ret = crypto_sig_verify(tfm, sig->s, sig->s_size, + sig->digest, sig->digest_size); + +error_free_key: + kfree_sensitive(key); +error_free_tfm: + crypto_free_sig(tfm); + pr_devel("<==%s() = %d\n", __func__, ret); + if (WARN_ON_ONCE(ret > 0)) + ret = -EINVAL; + return ret; +} +EXPORT_SYMBOL_GPL(public_key_verify_signature); + +static int public_key_verify_signature_2(const struct key *key, + const struct public_key_signature *sig) +{ + const struct public_key *pk = key->payload.data[asym_crypto]; + return public_key_verify_signature(pk, sig); +} + +/* + * Public key algorithm asymmetric key subtype + */ +struct asymmetric_key_subtype public_key_subtype = { + .owner = THIS_MODULE, + .name = "public_key", + .name_len = sizeof("public_key") - 1, + .describe = public_key_describe, + .destroy = public_key_destroy, + .query = software_key_query, + .eds_op = software_key_eds_op, + .verify_signature = public_key_verify_signature_2, +}; +EXPORT_SYMBOL_GPL(public_key_subtype); diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c new file mode 100644 index 000000000..6b69ea40d --- /dev/null +++ b/crypto/asymmetric_keys/restrict.c @@ -0,0 +1,359 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Instantiate a public key crypto key from an X.509 Certificate + * + * Copyright (C) 2012, 2016 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "ASYM: "fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/err.h> +#include <crypto/public_key.h> +#include "asymmetric_keys.h" + +static bool use_builtin_keys; +static struct asymmetric_key_id *ca_keyid; + +#ifndef MODULE +static struct { + struct asymmetric_key_id id; + unsigned char data[10]; +} cakey; + +static int __init ca_keys_setup(char *str) +{ + if (!str) /* default system keyring */ + return 1; + + if (strncmp(str, "id:", 3) == 0) { + struct asymmetric_key_id *p = &cakey.id; + size_t hexlen = (strlen(str) - 3) / 2; + int ret; + + if (hexlen == 0 || hexlen > sizeof(cakey.data)) { + pr_err("Missing or invalid ca_keys id\n"); + return 1; + } + + ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen); + if (ret < 0) + pr_err("Unparsable ca_keys id hex string\n"); + else + ca_keyid = p; /* owner key 'id:xxxxxx' */ + } else if (strcmp(str, "builtin") == 0) { + use_builtin_keys = true; + } + + return 1; +} +__setup("ca_keys=", ca_keys_setup); +#endif + +/** + * restrict_link_by_signature - Restrict additions to a ring of public keys + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trust_keyring: A ring of keys that can be used to vouch for the new cert. + * + * Check the new certificate against the ones in the trust keyring. If one of + * those is the signing key and validates the new certificate, then mark the + * new certificate as being trusted. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if we couldn't find a + * matching parent certificate in the trusted list, -EKEYREJECTED if the + * signature check fails or the key is blacklisted, -ENOPKG if the signature + * uses unsupported crypto, or some other error if there is a matching + * certificate but the signature check cannot be performed. + */ +int restrict_link_by_signature(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + const struct public_key_signature *sig; + struct key *key; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (!trust_keyring) + return -ENOKEY; + + if (type != &key_type_asymmetric) + return -EOPNOTSUPP; + + sig = payload->data[asym_auth]; + if (!sig) + return -ENOPKG; + if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2]) + return -ENOKEY; + + if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid)) + return -EPERM; + + /* See if we have a key that signed this one. */ + key = find_asymmetric_key(trust_keyring, + sig->auth_ids[0], sig->auth_ids[1], + sig->auth_ids[2], false); + if (IS_ERR(key)) + return -ENOKEY; + + if (use_builtin_keys && !test_bit(KEY_FLAG_BUILTIN, &key->flags)) + ret = -ENOKEY; + else + ret = verify_signature(key, sig); + key_put(key); + return ret; +} + +/** + * restrict_link_by_ca - Restrict additions to a ring of CA keys + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trust_keyring: Unused. + * + * Check if the new certificate is a CA. If it is a CA, then mark the new + * certificate as being ok to link. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if the + * certificate is not a CA. -ENOPKG if the signature uses unsupported + * crypto, or some other error if there is a matching certificate but + * the signature check cannot be performed. + */ +int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + const struct public_key *pkey; + + if (type != &key_type_asymmetric) + return -EOPNOTSUPP; + + pkey = payload->data[asym_crypto]; + if (!pkey) + return -ENOPKG; + if (!test_bit(KEY_EFLAG_CA, &pkey->key_eflags)) + return -ENOKEY; + if (!test_bit(KEY_EFLAG_KEYCERTSIGN, &pkey->key_eflags)) + return -ENOKEY; + if (!IS_ENABLED(CONFIG_INTEGRITY_CA_MACHINE_KEYRING_MAX)) + return 0; + if (test_bit(KEY_EFLAG_DIGITALSIG, &pkey->key_eflags)) + return -ENOKEY; + + return 0; +} + +/** + * restrict_link_by_digsig - Restrict additions to a ring of digsig keys + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trust_keyring: A ring of keys that can be used to vouch for the new cert. + * + * Check if the new certificate has digitalSignature usage set. If it is, + * then mark the new certificate as being ok to link. Afterwards verify + * the new certificate against the ones in the trust_keyring. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if the + * certificate is not a digsig. -ENOPKG if the signature uses unsupported + * crypto, or some other error if there is a matching certificate but + * the signature check cannot be performed. + */ +int restrict_link_by_digsig(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + const struct public_key *pkey; + + if (type != &key_type_asymmetric) + return -EOPNOTSUPP; + + pkey = payload->data[asym_crypto]; + + if (!pkey) + return -ENOPKG; + + if (!test_bit(KEY_EFLAG_DIGITALSIG, &pkey->key_eflags)) + return -ENOKEY; + + if (test_bit(KEY_EFLAG_CA, &pkey->key_eflags)) + return -ENOKEY; + + if (test_bit(KEY_EFLAG_KEYCERTSIGN, &pkey->key_eflags)) + return -ENOKEY; + + return restrict_link_by_signature(dest_keyring, type, payload, + trust_keyring); +} + +static bool match_either_id(const struct asymmetric_key_id **pair, + const struct asymmetric_key_id *single) +{ + return (asymmetric_key_id_same(pair[0], single) || + asymmetric_key_id_same(pair[1], single)); +} + +static int key_or_keyring_common(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trusted, bool check_dest) +{ + const struct public_key_signature *sig; + struct key *key = NULL; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (!dest_keyring) + return -ENOKEY; + else if (dest_keyring->type != &key_type_keyring) + return -EOPNOTSUPP; + + if (!trusted && !check_dest) + return -ENOKEY; + + if (type != &key_type_asymmetric) + return -EOPNOTSUPP; + + sig = payload->data[asym_auth]; + if (!sig) + return -ENOPKG; + if (!sig->auth_ids[0] && !sig->auth_ids[1] && !sig->auth_ids[2]) + return -ENOKEY; + + if (trusted) { + if (trusted->type == &key_type_keyring) { + /* See if we have a key that signed this one. */ + key = find_asymmetric_key(trusted, sig->auth_ids[0], + sig->auth_ids[1], + sig->auth_ids[2], false); + if (IS_ERR(key)) + key = NULL; + } else if (trusted->type == &key_type_asymmetric) { + const struct asymmetric_key_id **signer_ids; + + signer_ids = (const struct asymmetric_key_id **) + asymmetric_key_ids(trusted)->id; + + /* + * The auth_ids come from the candidate key (the + * one that is being considered for addition to + * dest_keyring) and identify the key that was + * used to sign. + * + * The signer_ids are identifiers for the + * signing key specified for dest_keyring. + * + * The first auth_id is the preferred id, 2nd and + * 3rd are the fallbacks. If exactly one of + * auth_ids[0] and auth_ids[1] is present, it may + * match either signer_ids[0] or signed_ids[1]. + * If both are present the first one may match + * either signed_id but the second one must match + * the second signer_id. If neither of them is + * available, auth_ids[2] is matched against + * signer_ids[2] as a fallback. + */ + if (!sig->auth_ids[0] && !sig->auth_ids[1]) { + if (asymmetric_key_id_same(signer_ids[2], + sig->auth_ids[2])) + key = __key_get(trusted); + + } else if (!sig->auth_ids[0] || !sig->auth_ids[1]) { + const struct asymmetric_key_id *auth_id; + + auth_id = sig->auth_ids[0] ?: sig->auth_ids[1]; + if (match_either_id(signer_ids, auth_id)) + key = __key_get(trusted); + + } else if (asymmetric_key_id_same(signer_ids[1], + sig->auth_ids[1]) && + match_either_id(signer_ids, + sig->auth_ids[0])) { + key = __key_get(trusted); + } + } else { + return -EOPNOTSUPP; + } + } + + if (check_dest && !key) { + /* See if the destination has a key that signed this one. */ + key = find_asymmetric_key(dest_keyring, sig->auth_ids[0], + sig->auth_ids[1], sig->auth_ids[2], + false); + if (IS_ERR(key)) + key = NULL; + } + + if (!key) + return -ENOKEY; + + ret = key_validate(key); + if (ret == 0) + ret = verify_signature(key, sig); + + key_put(key); + return ret; +} + +/** + * restrict_link_by_key_or_keyring - Restrict additions to a ring of public + * keys using the restrict_key information stored in the ring. + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trusted: A key or ring of keys that can be used to vouch for the new cert. + * + * Check the new certificate only against the key or keys passed in the data + * parameter. If one of those is the signing key and validates the new + * certificate, then mark the new certificate as being ok to link. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if we + * couldn't find a matching parent certificate in the trusted list, + * -EKEYREJECTED if the signature check fails, -ENOPKG if the signature uses + * unsupported crypto, or some other error if there is a matching certificate + * but the signature check cannot be performed. + */ +int restrict_link_by_key_or_keyring(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trusted) +{ + return key_or_keyring_common(dest_keyring, type, payload, trusted, + false); +} + +/** + * restrict_link_by_key_or_keyring_chain - Restrict additions to a ring of + * public keys using the restrict_key information stored in the ring. + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trusted: A key or ring of keys that can be used to vouch for the new cert. + * + * Check the new certificate against the key or keys passed in the data + * parameter and against the keys already linked to the destination keyring. If + * one of those is the signing key and validates the new certificate, then mark + * the new certificate as being ok to link. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if we + * couldn't find a matching parent certificate in the trusted list, + * -EKEYREJECTED if the signature check fails, -ENOPKG if the signature uses + * unsupported crypto, or some other error if there is a matching certificate + * but the signature check cannot be performed. + */ +int restrict_link_by_key_or_keyring_chain(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trusted) +{ + return key_or_keyring_common(dest_keyring, type, payload, trusted, + true); +} diff --git a/crypto/asymmetric_keys/selftest.c b/crypto/asymmetric_keys/selftest.c new file mode 100644 index 000000000..c50da7ef9 --- /dev/null +++ b/crypto/asymmetric_keys/selftest.c @@ -0,0 +1,231 @@ +/* Self-testing for signature checking. + * + * Copyright (C) 2022 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <crypto/pkcs7.h> +#include <linux/cred.h> +#include <linux/kernel.h> +#include <linux/key.h> +#include <linux/module.h> +#include "x509_parser.h" + +struct certs_test { + const u8 *data; + size_t data_len; + const u8 *pkcs7; + size_t pkcs7_len; +}; + +/* + * Set of X.509 certificates to provide public keys for the tests. These will + * be loaded into a temporary keyring for the duration of the testing. + */ +static const __initconst u8 certs_selftest_keys[] = { + "\x30\x82\x05\x55\x30\x82\x03\x3d\xa0\x03\x02\x01\x02\x02\x14\x73" + "\x98\xea\x98\x2d\xd0\x2e\xa8\xb1\xcf\x57\xc7\xf2\x97\xb3\xe6\x1a" + "\xfc\x8c\x0a\x30\x0d\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01\x01\x0b" + "\x05\x00\x30\x34\x31\x32\x30\x30\x06\x03\x55\x04\x03\x0c\x29\x43" + "\x65\x72\x74\x69\x66\x69\x63\x61\x74\x65\x20\x76\x65\x72\x69\x66" + "\x69\x63\x61\x74\x69\x6f\x6e\x20\x73\x65\x6c\x66\x2d\x74\x65\x73" + "\x74\x69\x6e\x67\x20\x6b\x65\x79\x30\x20\x17\x0d\x32\x32\x30\x35" + "\x31\x38\x32\x32\x33\x32\x34\x31\x5a\x18\x0f\x32\x31\x32\x32\x30" + "\x34\x32\x34\x32\x32\x33\x32\x34\x31\x5a\x30\x34\x31\x32\x30\x30" + "\x06\x03\x55\x04\x03\x0c\x29\x43\x65\x72\x74\x69\x66\x69\x63\x61" + "\x74\x65\x20\x76\x65\x72\x69\x66\x69\x63\x61\x74\x69\x6f\x6e\x20" + "\x73\x65\x6c\x66\x2d\x74\x65\x73\x74\x69\x6e\x67\x20\x6b\x65\x79" + "\x30\x82\x02\x22\x30\x0d\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01\x01" + "\x01\x05\x00\x03\x82\x02\x0f\x00\x30\x82\x02\x0a\x02\x82\x02\x01" + "\x00\xcc\xac\x49\xdd\x3b\xca\xb0\x15\x7e\x84\x6a\xb2\x0a\x69\x5f" + "\x1c\x0a\x61\x82\x3b\x4f\x2c\xa3\x95\x2c\x08\x58\x4b\xb1\x5d\x99" + "\xe0\xc3\xc1\x79\xc2\xb3\xeb\xc0\x1e\x6d\x3e\x54\x1d\xbd\xb7\x92" + "\x7b\x4d\xb5\x95\x58\xb2\x52\x2e\xc6\x24\x4b\x71\x63\x80\x32\x77" + "\xa7\x38\x5e\xdb\x72\xae\x6e\x0d\xec\xfb\xb6\x6d\x01\x7f\xe9\x55" + "\x66\xdf\xbf\x1d\x76\x78\x02\x31\xe8\xe5\x07\xf8\xb7\x82\x5c\x0d" + "\xd4\xbb\xfb\xa2\x59\x0d\x2e\x3a\x78\x95\x3a\x8b\x46\x06\x47\x44" + "\x46\xd7\xcd\x06\x6a\x41\x13\xe3\x19\xf6\xbb\x6e\x38\xf4\x83\x01" + "\xa3\xbf\x4a\x39\x4f\xd7\x0a\xe9\x38\xb3\xf5\x94\x14\x4e\xdd\xf7" + "\x43\xfd\x24\xb2\x49\x3c\xa5\xf7\x7a\x7c\xd4\x45\x3d\x97\x75\x68" + "\xf1\xed\x4c\x42\x0b\x70\xca\x85\xf3\xde\xe5\x88\x2c\xc5\xbe\xb6" + "\x97\x34\xba\x24\x02\xcd\x8b\x86\x9f\xa9\x73\xca\x73\xcf\x92\x81" + "\xee\x75\x55\xbb\x18\x67\x5c\xff\x3f\xb5\xdd\x33\x1b\x0c\xe9\x78" + "\xdb\x5c\xcf\xaa\x5c\x43\x42\xdf\x5e\xa9\x6d\xec\xd7\xd7\xff\xe6" + "\xa1\x3a\x92\x1a\xda\xae\xf6\x8c\x6f\x7b\xd5\xb4\x6e\x06\xe9\x8f" + "\xe8\xde\x09\x31\x89\xed\x0e\x11\xa1\xfa\x8a\xe9\xe9\x64\x59\x62" + "\x53\xda\xd1\x70\xbe\x11\xd4\x99\x97\x11\xcf\x99\xde\x0b\x9d\x94" + "\x7e\xaa\xb8\x52\xea\x37\xdb\x90\x7e\x35\xbd\xd9\xfe\x6d\x0a\x48" + "\x70\x28\xdd\xd5\x0d\x7f\x03\x80\x93\x14\x23\x8f\xb9\x22\xcd\x7c" + "\x29\xfe\xf1\x72\xb5\x5c\x0b\x12\xcf\x9c\x15\xf6\x11\x4c\x7a\x45" + "\x25\x8c\x45\x0a\x34\xac\x2d\x9a\x81\xca\x0b\x13\x22\xcd\xeb\x1a" + "\x38\x88\x18\x97\x96\x08\x81\xaa\xcc\x8f\x0f\x8a\x32\x7b\x76\x68" + "\x03\x68\x43\xbf\x11\xba\x55\x60\xfd\x80\x1c\x0d\x9b\x69\xb6\x09" + "\x72\xbc\x0f\x41\x2f\x07\x82\xc6\xe3\xb2\x13\x91\xc4\x6d\x14\x95" + "\x31\xbe\x19\xbd\xbc\xed\xe1\x4c\x74\xa2\xe0\x78\x0b\xbb\x94\xec" + "\x4c\x53\x3a\xa2\xb5\x84\x1d\x4b\x65\x7e\xdc\xf7\xdb\x36\x7d\xbe" + "\x9e\x3b\x36\x66\x42\x66\x76\x35\xbf\xbe\xf0\xc1\x3c\x7c\xe9\x42" + "\x5c\x24\x53\x03\x05\xa8\x67\x24\x50\x02\x75\xff\x24\x46\x3b\x35" + "\x89\x76\xe6\x70\xda\xc5\x51\x8c\x9a\xe5\x05\xb0\x0b\xd0\x2d\xd4" + "\x7d\x57\x75\x94\x6b\xf9\x0a\xad\x0e\x41\x00\x15\xd0\x4f\xc0\x7f" + "\x90\x2d\x18\x48\x8f\x28\xfe\x5d\xa7\xcd\x99\x9e\xbd\x02\x6c\x8a" + "\x31\xf3\x1c\xc7\x4b\xe6\x93\xcd\x42\xa2\xe4\x68\x10\x47\x9d\xfc" + "\x21\x02\x03\x01\x00\x01\xa3\x5d\x30\x5b\x30\x0c\x06\x03\x55\x1d" + "\x13\x01\x01\xff\x04\x02\x30\x00\x30\x0b\x06\x03\x55\x1d\x0f\x04" + "\x04\x03\x02\x07\x80\x30\x1d\x06\x03\x55\x1d\x0e\x04\x16\x04\x14" + "\xf5\x87\x03\xbb\x33\xce\x1b\x73\xee\x02\xec\xcd\xee\x5b\x88\x17" + "\x51\x8f\xe3\xdb\x30\x1f\x06\x03\x55\x1d\x23\x04\x18\x30\x16\x80" + "\x14\xf5\x87\x03\xbb\x33\xce\x1b\x73\xee\x02\xec\xcd\xee\x5b\x88" + "\x17\x51\x8f\xe3\xdb\x30\x0d\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01" + "\x01\x0b\x05\x00\x03\x82\x02\x01\x00\xc0\x2e\x12\x41\x7b\x73\x85" + "\x16\xc8\xdb\x86\x79\xe8\xf5\xcd\x44\xf4\xc6\xe2\x81\x23\x5e\x47" + "\xcb\xab\x25\xf1\x1e\x58\x3e\x31\x7f\x78\xad\x85\xeb\xfe\x14\x88" + "\x60\xf7\x7f\xd2\x26\xa2\xf4\x98\x2a\xfd\xba\x05\x0c\x20\x33\x12" + "\xcc\x4d\x14\x61\x64\x81\x93\xd3\x33\xed\xc8\xff\xf1\x78\xcc\x5f" + "\x51\x9f\x09\xd7\xbe\x0d\x5c\x74\xfd\x9b\xdf\x52\x4a\xc9\xa8\x71" + "\x25\x33\x04\x10\x67\x36\xd0\xb3\x0b\xc9\xa1\x40\x72\xae\x41\x7b" + "\x68\xe6\xe4\x7b\xd0\x28\xf7\x6d\xe7\x3f\x50\xfc\x91\x7c\x91\x56" + "\xd4\xdf\xa6\xbb\xe8\x4d\x1b\x58\xaa\x28\xfa\xc1\x19\xeb\x11\x2f" + "\x24\x8b\x7c\xc5\xa9\x86\x26\xaa\x6e\xb7\x9b\xd5\xf8\x06\xfb\x02" + "\x52\x7b\x9c\x9e\xa1\xe0\x07\x8b\x5e\xe4\xb8\x55\x29\xf6\x48\x52" + "\x1c\x1b\x54\x2d\x46\xd8\xe5\x71\xb9\x60\xd1\x45\xb5\x92\x89\x8a" + "\x63\x58\x2a\xb3\xc6\xb2\x76\xe2\x3c\x82\x59\x04\xae\x5a\xc4\x99" + "\x7b\x2e\x4b\x46\x57\xb8\x29\x24\xb2\xfd\xee\x2c\x0d\xa4\x83\xfa" + "\x65\x2a\x07\x35\x8b\x97\xcf\xbd\x96\x2e\xd1\x7e\x6c\xc2\x1e\x87" + "\xb6\x6c\x76\x65\xb5\xb2\x62\xda\x8b\xe9\x73\xe3\xdb\x33\xdd\x13" + "\x3a\x17\x63\x6a\x76\xde\x8d\x8f\xe0\x47\x61\x28\x3a\x83\xff\x8f" + "\xe7\xc7\xe0\x4a\xa3\xe5\x07\xcf\xe9\x8c\x35\x35\x2e\xe7\x80\x66" + "\x31\xbf\x91\x58\x0a\xe1\x25\x3d\x38\xd3\xa4\xf0\x59\x34\x47\x07" + "\x62\x0f\xbe\x30\xdd\x81\x88\x58\xf0\x28\xb0\x96\xe5\x82\xf8\x05" + "\xb7\x13\x01\xbc\xfa\xc6\x1f\x86\x72\xcc\xf9\xee\x8e\xd9\xd6\x04" + "\x8c\x24\x6c\xbf\x0f\x5d\x37\x39\xcf\x45\xc1\x93\x3a\xd2\xed\x5c" + "\x58\x79\x74\x86\x62\x30\x7e\x8e\xbb\xdd\x7a\xa9\xed\xca\x40\xcb" + "\x62\x47\xf4\xb4\x9f\x52\x7f\x72\x63\xa8\xf0\x2b\xaf\x45\x2a\x48" + "\x19\x6d\xe3\xfb\xf9\x19\x66\x69\xc8\xcc\x62\x87\x6c\x53\x2b\x2d" + "\x6e\x90\x6c\x54\x3a\x82\x25\x41\xcb\x18\x6a\xa4\x22\xa8\xa1\xc4" + "\x47\xd7\x81\x00\x1c\x15\x51\x0f\x1a\xaf\xef\x9f\xa6\x61\x8c\xbd" + "\x6b\x8b\xed\xe6\xac\x0e\xb6\x3a\x4c\x92\xe6\x0f\x91\x0a\x0f\x71" + "\xc7\xa0\xb9\x0d\x3a\x17\x5a\x6f\x35\xc8\xe7\x50\x4f\x46\xe8\x70" + "\x60\x48\x06\x82\x8b\x66\x58\xe6\x73\x91\x9c\x12\x3d\x35\x8e\x46" + "\xad\x5a\xf5\xb3\xdb\x69\x21\x04\xfd\xd3\x1c\xdf\x94\x9d\x56\xb0" + "\x0a\xd1\x95\x76\x8d\xec\x9e\xdd\x0b\x15\x97\x64\xad\xe5\xf2\x62" + "\x02\xfc\x9e\x5f\x56\x42\x39\x05\xb3" +}; + +/* + * Signed data and detached signature blobs that form the verification tests. + */ +static const __initconst u8 certs_selftest_1_data[] = { + "\x54\x68\x69\x73\x20\x69\x73\x20\x73\x6f\x6d\x65\x20\x74\x65\x73" + "\x74\x20\x64\x61\x74\x61\x20\x75\x73\x65\x64\x20\x66\x6f\x72\x20" + "\x73\x65\x6c\x66\x2d\x74\x65\x73\x74\x69\x6e\x67\x20\x63\x65\x72" + "\x74\x69\x66\x69\x63\x61\x74\x65\x20\x76\x65\x72\x69\x66\x69\x63" + "\x61\x74\x69\x6f\x6e\x2e\x0a" +}; + +static const __initconst u8 certs_selftest_1_pkcs7[] = { + "\x30\x82\x02\xab\x06\x09\x2a\x86\x48\x86\xf7\x0d\x01\x07\x02\xa0" + "\x82\x02\x9c\x30\x82\x02\x98\x02\x01\x01\x31\x0d\x30\x0b\x06\x09" + "\x60\x86\x48\x01\x65\x03\x04\x02\x01\x30\x0b\x06\x09\x2a\x86\x48" + "\x86\xf7\x0d\x01\x07\x01\x31\x82\x02\x75\x30\x82\x02\x71\x02\x01" + "\x01\x30\x4c\x30\x34\x31\x32\x30\x30\x06\x03\x55\x04\x03\x0c\x29" + "\x43\x65\x72\x74\x69\x66\x69\x63\x61\x74\x65\x20\x76\x65\x72\x69" + "\x66\x69\x63\x61\x74\x69\x6f\x6e\x20\x73\x65\x6c\x66\x2d\x74\x65" + "\x73\x74\x69\x6e\x67\x20\x6b\x65\x79\x02\x14\x73\x98\xea\x98\x2d" + "\xd0\x2e\xa8\xb1\xcf\x57\xc7\xf2\x97\xb3\xe6\x1a\xfc\x8c\x0a\x30" + "\x0b\x06\x09\x60\x86\x48\x01\x65\x03\x04\x02\x01\x30\x0d\x06\x09" + "\x2a\x86\x48\x86\xf7\x0d\x01\x01\x01\x05\x00\x04\x82\x02\x00\xac" + "\xb0\xf2\x07\xd6\x99\x6d\xc0\xc0\xd9\x8d\x31\x0d\x7e\x04\xeb\xc3" + "\x88\x90\xc4\x58\x46\xd4\xe2\xa0\xa3\x25\xe3\x04\x50\x37\x85\x8c" + "\x91\xc6\xfc\xc5\xd4\x92\xfd\x05\xd8\xb8\xa3\xb8\xba\x89\x13\x00" + "\x88\x79\x99\x51\x6b\x5b\x28\x31\xc0\xb3\x1b\x7a\x68\x2c\x00\xdb" + "\x4b\x46\x11\xf3\xfa\x50\x8e\x19\x89\xa2\x4c\xda\x4c\x89\x01\x11" + "\x89\xee\xd3\xc8\xc1\xe7\xa7\xf6\xb2\xa2\xf8\x65\xb8\x35\x20\x33" + "\xba\x12\x62\xd5\xbd\xaa\x71\xe5\x5b\xc0\x6a\x32\xff\x6a\x2e\x23" + "\xef\x2b\xb6\x58\xb1\xfb\x5f\x82\x34\x40\x6d\x9f\xbc\x27\xac\x37" + "\x23\x99\xcf\x7d\x20\xb2\x39\x01\xc0\x12\xce\xd7\x5d\x2f\xb6\xab" + "\xb5\x56\x4f\xef\xf4\x72\x07\x58\x65\xa9\xeb\x1f\x75\x1c\x5f\x0c" + "\x88\xe0\xa4\xe2\xcd\x73\x2b\x9e\xb2\x05\x7e\x12\xf8\xd0\x66\x41" + "\xcc\x12\x63\xd4\xd6\xac\x9b\x1d\x14\x77\x8d\x1c\x57\xd5\x27\xc6" + "\x49\xa2\x41\x43\xf3\x59\x29\xe5\xcb\xd1\x75\xbc\x3a\x97\x2a\x72" + "\x22\x66\xc5\x3b\xc1\xba\xfc\x53\x18\x98\xe2\x21\x64\xc6\x52\x87" + "\x13\xd5\x7c\x42\xe8\xfb\x9c\x9a\x45\x32\xd5\xa5\x22\x62\x9d\xd4" + "\xcb\xa4\xfa\x77\xbb\x50\x24\x0b\x8b\x88\x99\x15\x56\xa9\x1e\x92" + "\xbf\x5d\x94\x77\xb6\xf1\x67\x01\x60\x06\x58\x5c\xdf\x18\x52\x79" + "\x37\x30\x93\x7d\x87\x04\xf1\xe0\x55\x59\x52\xf3\xc2\xb1\x1c\x5b" + "\x12\x7c\x49\x87\xfb\xf7\xed\xdd\x95\x71\xec\x4b\x1a\x85\x08\xb0" + "\xa0\x36\xc4\x7b\xab\x40\xe0\xf1\x98\xcc\xaf\x19\x40\x8f\x47\x6f" + "\xf0\x6c\x84\x29\x7f\x7f\x04\x46\xcb\x08\x0f\xe0\xc1\xc9\x70\x6e" + "\x95\x3b\xa4\xbc\x29\x2b\x53\x67\x45\x1b\x0d\xbc\x13\xa5\x76\x31" + "\xaf\xb9\xd0\xe0\x60\x12\xd2\xf4\xb7\x7c\x58\x7e\xf6\x2d\xbb\x24" + "\x14\x5a\x20\x24\xa8\x12\xdf\x25\xbd\x42\xce\x96\x7c\x2e\xba\x14" + "\x1b\x81\x9f\x18\x45\xa4\xc6\x70\x3e\x0e\xf0\xd3\x7b\x9c\x10\xbe" + "\xb8\x7a\x89\xc5\x9e\xd9\x97\xdf\xd7\xe7\xc6\x1d\xc0\x20\x6c\xb8" + "\x1e\x3a\x63\xb8\x39\x8e\x8e\x62\xd5\xd2\xb4\xcd\xff\x46\xfc\x8e" + "\xec\x07\x35\x0c\xff\xb0\x05\xe6\xf4\xe5\xfe\xa2\xe3\x0a\xe6\x36" + "\xa7\x4a\x7e\x62\x1d\xc4\x50\x39\x35\x4e\x28\xcb\x4a\xfb\x9d\xdb" + "\xdd\x23\xd6\x53\xb1\x74\x77\x12\xf7\x9c\xf0\x9a\x6b\xf7\xa9\x64" + "\x2d\x86\x21\x2a\xcf\xc6\x54\xf5\xc9\xad\xfa\xb5\x12\xb4\xf3\x51" + "\x77\x55\x3c\x6f\x0c\x32\xd3\x8c\x44\x39\x71\x25\xfe\x96\xd2" +}; + +/* + * List of tests to be run. + */ +#define TEST(data, pkcs7) { data, sizeof(data) - 1, pkcs7, sizeof(pkcs7) - 1 } +static const struct certs_test certs_tests[] __initconst = { + TEST(certs_selftest_1_data, certs_selftest_1_pkcs7), +}; + +static int __init fips_signature_selftest(void) +{ + struct key *keyring; + int ret, i; + + pr_notice("Running certificate verification selftests\n"); + + keyring = keyring_alloc(".certs_selftest", + GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(), + (KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ | + KEY_USR_SEARCH, + KEY_ALLOC_NOT_IN_QUOTA, + NULL, NULL); + if (IS_ERR(keyring)) + panic("Can't allocate certs selftest keyring: %ld\n", + PTR_ERR(keyring)); + + ret = x509_load_certificate_list(certs_selftest_keys, + sizeof(certs_selftest_keys) - 1, keyring); + if (ret < 0) + panic("Can't allocate certs selftest keyring: %d\n", ret); + + for (i = 0; i < ARRAY_SIZE(certs_tests); i++) { + const struct certs_test *test = &certs_tests[i]; + struct pkcs7_message *pkcs7; + + pkcs7 = pkcs7_parse_message(test->pkcs7, test->pkcs7_len); + if (IS_ERR(pkcs7)) + panic("Certs selftest %d: pkcs7_parse_message() = %d\n", i, ret); + + pkcs7_supply_detached_data(pkcs7, test->data, test->data_len); + + ret = pkcs7_verify(pkcs7, VERIFYING_MODULE_SIGNATURE); + if (ret < 0) + panic("Certs selftest %d: pkcs7_verify() = %d\n", i, ret); + + ret = pkcs7_validate_trust(pkcs7, keyring); + if (ret < 0) + panic("Certs selftest %d: pkcs7_validate_trust() = %d\n", i, ret); + + pkcs7_free_message(pkcs7); + } + + key_put(keyring); + return 0; +} + +late_initcall(fips_signature_selftest); + +MODULE_DESCRIPTION("X.509 self tests"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); diff --git a/crypto/asymmetric_keys/signature.c b/crypto/asymmetric_keys/signature.c new file mode 100644 index 000000000..2deff81f8 --- /dev/null +++ b/crypto/asymmetric_keys/signature.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Signature verification with an asymmetric key + * + * See Documentation/crypto/asymmetric-keys.rst + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "SIG: "fmt +#include <keys/asymmetric-subtype.h> +#include <linux/export.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/keyctl.h> +#include <crypto/public_key.h> +#include <keys/user-type.h> +#include "asymmetric_keys.h" + +/* + * Destroy a public key signature. + */ +void public_key_signature_free(struct public_key_signature *sig) +{ + int i; + + if (sig) { + for (i = 0; i < ARRAY_SIZE(sig->auth_ids); i++) + kfree(sig->auth_ids[i]); + kfree(sig->s); + kfree(sig->digest); + kfree(sig); + } +} +EXPORT_SYMBOL_GPL(public_key_signature_free); + +/** + * query_asymmetric_key - Get information about an asymmetric key. + * @params: Various parameters. + * @info: Where to put the information. + */ +int query_asymmetric_key(const struct kernel_pkey_params *params, + struct kernel_pkey_query *info) +{ + const struct asymmetric_key_subtype *subtype; + struct key *key = params->key; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (key->type != &key_type_asymmetric) + return -EINVAL; + subtype = asymmetric_key_subtype(key); + if (!subtype || + !key->payload.data[0]) + return -EINVAL; + if (!subtype->query) + return -ENOTSUPP; + + ret = subtype->query(params, info); + + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(query_asymmetric_key); + +/** + * encrypt_blob - Encrypt data using an asymmetric key + * @params: Various parameters + * @data: Data blob to be encrypted, length params->data_len + * @enc: Encrypted data buffer, length params->enc_len + * + * Encrypt the specified data blob using the private key specified by + * params->key. The encrypted data is wrapped in an encoding if + * params->encoding is specified (eg. "pkcs1"). + * + * Returns the length of the data placed in the encrypted data buffer or an + * error. + */ +int encrypt_blob(struct kernel_pkey_params *params, + const void *data, void *enc) +{ + params->op = kernel_pkey_encrypt; + return asymmetric_key_eds_op(params, data, enc); +} +EXPORT_SYMBOL_GPL(encrypt_blob); + +/** + * decrypt_blob - Decrypt data using an asymmetric key + * @params: Various parameters + * @enc: Encrypted data to be decrypted, length params->enc_len + * @data: Decrypted data buffer, length params->data_len + * + * Decrypt the specified data blob using the private key specified by + * params->key. The decrypted data is wrapped in an encoding if + * params->encoding is specified (eg. "pkcs1"). + * + * Returns the length of the data placed in the decrypted data buffer or an + * error. + */ +int decrypt_blob(struct kernel_pkey_params *params, + const void *enc, void *data) +{ + params->op = kernel_pkey_decrypt; + return asymmetric_key_eds_op(params, enc, data); +} +EXPORT_SYMBOL_GPL(decrypt_blob); + +/** + * create_signature - Sign some data using an asymmetric key + * @params: Various parameters + * @data: Data blob to be signed, length params->data_len + * @enc: Signature buffer, length params->enc_len + * + * Sign the specified data blob using the private key specified by params->key. + * The signature is wrapped in an encoding if params->encoding is specified + * (eg. "pkcs1"). If the encoding needs to know the digest type, this can be + * passed through params->hash_algo (eg. "sha1"). + * + * Returns the length of the data placed in the signature buffer or an error. + */ +int create_signature(struct kernel_pkey_params *params, + const void *data, void *enc) +{ + params->op = kernel_pkey_sign; + return asymmetric_key_eds_op(params, data, enc); +} +EXPORT_SYMBOL_GPL(create_signature); + +/** + * verify_signature - Initiate the use of an asymmetric key to verify a signature + * @key: The asymmetric key to verify against + * @sig: The signature to check + * + * Returns 0 if successful or else an error. + */ +int verify_signature(const struct key *key, + const struct public_key_signature *sig) +{ + const struct asymmetric_key_subtype *subtype; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (key->type != &key_type_asymmetric) + return -EINVAL; + subtype = asymmetric_key_subtype(key); + if (!subtype || + !key->payload.data[0]) + return -EINVAL; + if (!subtype->verify_signature) + return -ENOTSUPP; + + ret = subtype->verify_signature(key, sig); + + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_signature); diff --git a/crypto/asymmetric_keys/verify_pefile.c b/crypto/asymmetric_keys/verify_pefile.c new file mode 100644 index 000000000..f440767bd --- /dev/null +++ b/crypto/asymmetric_keys/verify_pefile.c @@ -0,0 +1,456 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Parse a signed PE binary + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "PEFILE: "fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/pe.h> +#include <linux/asn1.h> +#include <linux/verification.h> +#include <crypto/hash.h> +#include "verify_pefile.h" + +/* + * Parse a PE binary. + */ +static int pefile_parse_binary(const void *pebuf, unsigned int pelen, + struct pefile_context *ctx) +{ + const struct mz_hdr *mz = pebuf; + const struct pe_hdr *pe; + const struct pe32_opt_hdr *pe32; + const struct pe32plus_opt_hdr *pe64; + const struct data_directory *ddir; + const struct data_dirent *dde; + const struct section_header *secs, *sec; + size_t cursor, datalen = pelen; + + kenter(""); + +#define chkaddr(base, x, s) \ + do { \ + if ((x) < base || (s) >= datalen || (x) > datalen - (s)) \ + return -ELIBBAD; \ + } while (0) + + chkaddr(0, 0, sizeof(*mz)); + if (mz->magic != MZ_MAGIC) + return -ELIBBAD; + cursor = sizeof(*mz); + + chkaddr(cursor, mz->peaddr, sizeof(*pe)); + pe = pebuf + mz->peaddr; + if (pe->magic != PE_MAGIC) + return -ELIBBAD; + cursor = mz->peaddr + sizeof(*pe); + + chkaddr(0, cursor, sizeof(pe32->magic)); + pe32 = pebuf + cursor; + pe64 = pebuf + cursor; + + switch (pe32->magic) { + case PE_OPT_MAGIC_PE32: + chkaddr(0, cursor, sizeof(*pe32)); + ctx->image_checksum_offset = + (unsigned long)&pe32->csum - (unsigned long)pebuf; + ctx->header_size = pe32->header_size; + cursor += sizeof(*pe32); + ctx->n_data_dirents = pe32->data_dirs; + break; + + case PE_OPT_MAGIC_PE32PLUS: + chkaddr(0, cursor, sizeof(*pe64)); + ctx->image_checksum_offset = + (unsigned long)&pe64->csum - (unsigned long)pebuf; + ctx->header_size = pe64->header_size; + cursor += sizeof(*pe64); + ctx->n_data_dirents = pe64->data_dirs; + break; + + default: + pr_warn("Unknown PEOPT magic = %04hx\n", pe32->magic); + return -ELIBBAD; + } + + pr_debug("checksum @ %x\n", ctx->image_checksum_offset); + pr_debug("header size = %x\n", ctx->header_size); + + if (cursor >= ctx->header_size || ctx->header_size >= datalen) + return -ELIBBAD; + + if (ctx->n_data_dirents > (ctx->header_size - cursor) / sizeof(*dde)) + return -ELIBBAD; + + ddir = pebuf + cursor; + cursor += sizeof(*dde) * ctx->n_data_dirents; + + ctx->cert_dirent_offset = + (unsigned long)&ddir->certs - (unsigned long)pebuf; + ctx->certs_size = ddir->certs.size; + + if (!ddir->certs.virtual_address || !ddir->certs.size) { + pr_warn("Unsigned PE binary\n"); + return -ENODATA; + } + + chkaddr(ctx->header_size, ddir->certs.virtual_address, + ddir->certs.size); + ctx->sig_offset = ddir->certs.virtual_address; + ctx->sig_len = ddir->certs.size; + pr_debug("cert = %x @%x [%*ph]\n", + ctx->sig_len, ctx->sig_offset, + ctx->sig_len, pebuf + ctx->sig_offset); + + ctx->n_sections = pe->sections; + if (ctx->n_sections > (ctx->header_size - cursor) / sizeof(*sec)) + return -ELIBBAD; + ctx->secs = secs = pebuf + cursor; + + return 0; +} + +/* + * Check and strip the PE wrapper from around the signature and check that the + * remnant looks something like PKCS#7. + */ +static int pefile_strip_sig_wrapper(const void *pebuf, + struct pefile_context *ctx) +{ + struct win_certificate wrapper; + const u8 *pkcs7; + unsigned len; + + if (ctx->sig_len < sizeof(wrapper)) { + pr_warn("Signature wrapper too short\n"); + return -ELIBBAD; + } + + memcpy(&wrapper, pebuf + ctx->sig_offset, sizeof(wrapper)); + pr_debug("sig wrapper = { %x, %x, %x }\n", + wrapper.length, wrapper.revision, wrapper.cert_type); + + /* sbsign rounds up the length of certificate table (in optional + * header data directories) to 8 byte alignment. However, the PE + * specification states that while entries are 8-byte aligned, this is + * not included in their length, and as a result, pesign has not + * rounded up since 0.110. + */ + if (wrapper.length > ctx->sig_len) { + pr_warn("Signature wrapper bigger than sig len (%x > %x)\n", + ctx->sig_len, wrapper.length); + return -ELIBBAD; + } + if (wrapper.revision != WIN_CERT_REVISION_2_0) { + pr_warn("Signature is not revision 2.0\n"); + return -ENOTSUPP; + } + if (wrapper.cert_type != WIN_CERT_TYPE_PKCS_SIGNED_DATA) { + pr_warn("Signature certificate type is not PKCS\n"); + return -ENOTSUPP; + } + + /* It looks like the pkcs signature length in wrapper->length and the + * size obtained from the data dir entries, which lists the total size + * of certificate table, are both aligned to an octaword boundary, so + * we may have to deal with some padding. + */ + ctx->sig_len = wrapper.length; + ctx->sig_offset += sizeof(wrapper); + ctx->sig_len -= sizeof(wrapper); + if (ctx->sig_len < 4) { + pr_warn("Signature data missing\n"); + return -EKEYREJECTED; + } + + /* What's left should be a PKCS#7 cert */ + pkcs7 = pebuf + ctx->sig_offset; + if (pkcs7[0] != (ASN1_CONS_BIT | ASN1_SEQ)) + goto not_pkcs7; + + switch (pkcs7[1]) { + case 0 ... 0x7f: + len = pkcs7[1] + 2; + goto check_len; + case ASN1_INDEFINITE_LENGTH: + return 0; + case 0x81: + len = pkcs7[2] + 3; + goto check_len; + case 0x82: + len = ((pkcs7[2] << 8) | pkcs7[3]) + 4; + goto check_len; + case 0x83 ... 0xff: + return -EMSGSIZE; + default: + goto not_pkcs7; + } + +check_len: + if (len <= ctx->sig_len) { + /* There may be padding */ + ctx->sig_len = len; + return 0; + } +not_pkcs7: + pr_warn("Signature data not PKCS#7\n"); + return -ELIBBAD; +} + +/* + * Compare two sections for canonicalisation. + */ +static int pefile_compare_shdrs(const void *a, const void *b) +{ + const struct section_header *shdra = a; + const struct section_header *shdrb = b; + int rc; + + if (shdra->data_addr > shdrb->data_addr) + return 1; + if (shdrb->data_addr > shdra->data_addr) + return -1; + + if (shdra->virtual_address > shdrb->virtual_address) + return 1; + if (shdrb->virtual_address > shdra->virtual_address) + return -1; + + rc = strcmp(shdra->name, shdrb->name); + if (rc != 0) + return rc; + + if (shdra->virtual_size > shdrb->virtual_size) + return 1; + if (shdrb->virtual_size > shdra->virtual_size) + return -1; + + if (shdra->raw_data_size > shdrb->raw_data_size) + return 1; + if (shdrb->raw_data_size > shdra->raw_data_size) + return -1; + + return 0; +} + +/* + * Load the contents of the PE binary into the digest, leaving out the image + * checksum and the certificate data block. + */ +static int pefile_digest_pe_contents(const void *pebuf, unsigned int pelen, + struct pefile_context *ctx, + struct shash_desc *desc) +{ + unsigned *canon, tmp, loop, i, hashed_bytes; + int ret; + + /* Digest the header and data directory, but leave out the image + * checksum and the data dirent for the signature. + */ + ret = crypto_shash_update(desc, pebuf, ctx->image_checksum_offset); + if (ret < 0) + return ret; + + tmp = ctx->image_checksum_offset + sizeof(uint32_t); + ret = crypto_shash_update(desc, pebuf + tmp, + ctx->cert_dirent_offset - tmp); + if (ret < 0) + return ret; + + tmp = ctx->cert_dirent_offset + sizeof(struct data_dirent); + ret = crypto_shash_update(desc, pebuf + tmp, ctx->header_size - tmp); + if (ret < 0) + return ret; + + canon = kcalloc(ctx->n_sections, sizeof(unsigned), GFP_KERNEL); + if (!canon) + return -ENOMEM; + + /* We have to canonicalise the section table, so we perform an + * insertion sort. + */ + canon[0] = 0; + for (loop = 1; loop < ctx->n_sections; loop++) { + for (i = 0; i < loop; i++) { + if (pefile_compare_shdrs(&ctx->secs[canon[i]], + &ctx->secs[loop]) > 0) { + memmove(&canon[i + 1], &canon[i], + (loop - i) * sizeof(canon[0])); + break; + } + } + canon[i] = loop; + } + + hashed_bytes = ctx->header_size; + for (loop = 0; loop < ctx->n_sections; loop++) { + i = canon[loop]; + if (ctx->secs[i].raw_data_size == 0) + continue; + ret = crypto_shash_update(desc, + pebuf + ctx->secs[i].data_addr, + ctx->secs[i].raw_data_size); + if (ret < 0) { + kfree(canon); + return ret; + } + hashed_bytes += ctx->secs[i].raw_data_size; + } + kfree(canon); + + if (pelen > hashed_bytes) { + tmp = hashed_bytes + ctx->certs_size; + ret = crypto_shash_update(desc, + pebuf + hashed_bytes, + pelen - tmp); + if (ret < 0) + return ret; + } + + return 0; +} + +/* + * Digest the contents of the PE binary, leaving out the image checksum and the + * certificate data block. + */ +static int pefile_digest_pe(const void *pebuf, unsigned int pelen, + struct pefile_context *ctx) +{ + struct crypto_shash *tfm; + struct shash_desc *desc; + size_t digest_size, desc_size; + void *digest; + int ret; + + kenter(",%s", ctx->digest_algo); + + /* Allocate the hashing algorithm we're going to need and find out how + * big the hash operational data will be. + */ + tfm = crypto_alloc_shash(ctx->digest_algo, 0, 0); + if (IS_ERR(tfm)) + return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm); + + desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); + digest_size = crypto_shash_digestsize(tfm); + + if (digest_size != ctx->digest_len) { + pr_warn("Digest size mismatch (%zx != %x)\n", + digest_size, ctx->digest_len); + ret = -EBADMSG; + goto error_no_desc; + } + pr_debug("Digest: desc=%zu size=%zu\n", desc_size, digest_size); + + ret = -ENOMEM; + desc = kzalloc(desc_size + digest_size, GFP_KERNEL); + if (!desc) + goto error_no_desc; + + desc->tfm = tfm; + ret = crypto_shash_init(desc); + if (ret < 0) + goto error; + + ret = pefile_digest_pe_contents(pebuf, pelen, ctx, desc); + if (ret < 0) + goto error; + + digest = (void *)desc + desc_size; + ret = crypto_shash_final(desc, digest); + if (ret < 0) + goto error; + + pr_debug("Digest calc = [%*ph]\n", ctx->digest_len, digest); + + /* Check that the PE file digest matches that in the MSCODE part of the + * PKCS#7 certificate. + */ + if (memcmp(digest, ctx->digest, ctx->digest_len) != 0) { + pr_warn("Digest mismatch\n"); + ret = -EKEYREJECTED; + } else { + pr_debug("The digests match!\n"); + } + +error: + kfree_sensitive(desc); +error_no_desc: + crypto_free_shash(tfm); + kleave(" = %d", ret); + return ret; +} + +/** + * verify_pefile_signature - Verify the signature on a PE binary image + * @pebuf: Buffer containing the PE binary image + * @pelen: Length of the binary image + * @trusted_keys: Signing certificate(s) to use as starting points + * @usage: The use to which the key is being put. + * + * Validate that the certificate chain inside the PKCS#7 message inside the PE + * binary image intersects keys we already know and trust. + * + * Returns, in order of descending priority: + * + * (*) -ELIBBAD if the image cannot be parsed, or: + * + * (*) -EKEYREJECTED if a signature failed to match for which we have a valid + * key, or: + * + * (*) 0 if at least one signature chain intersects with the keys in the trust + * keyring, or: + * + * (*) -ENODATA if there is no signature present. + * + * (*) -ENOPKG if a suitable crypto module couldn't be found for a check on a + * chain. + * + * (*) -ENOKEY if we couldn't find a match for any of the signature chains in + * the message. + * + * May also return -ENOMEM. + */ +int verify_pefile_signature(const void *pebuf, unsigned pelen, + struct key *trusted_keys, + enum key_being_used_for usage) +{ + struct pefile_context ctx; + int ret; + + kenter(""); + + memset(&ctx, 0, sizeof(ctx)); + ret = pefile_parse_binary(pebuf, pelen, &ctx); + if (ret < 0) + return ret; + + ret = pefile_strip_sig_wrapper(pebuf, &ctx); + if (ret < 0) + return ret; + + ret = verify_pkcs7_signature(NULL, 0, + pebuf + ctx.sig_offset, ctx.sig_len, + trusted_keys, usage, + mscode_parse, &ctx); + if (ret < 0) + goto error; + + pr_debug("Digest: %u [%*ph]\n", + ctx.digest_len, ctx.digest_len, ctx.digest); + + /* Generate the digest and check against the PKCS7 certificate + * contents. + */ + ret = pefile_digest_pe(pebuf, pelen, &ctx); + +error: + kfree_sensitive(ctx.digest); + return ret; +} diff --git a/crypto/asymmetric_keys/verify_pefile.h b/crypto/asymmetric_keys/verify_pefile.h new file mode 100644 index 000000000..e1628e100 --- /dev/null +++ b/crypto/asymmetric_keys/verify_pefile.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* PE Binary parser bits + * + * Copyright (C) 2014 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <crypto/pkcs7.h> +#include <crypto/hash_info.h> + +struct pefile_context { + unsigned header_size; + unsigned image_checksum_offset; + unsigned cert_dirent_offset; + unsigned n_data_dirents; + unsigned n_sections; + unsigned certs_size; + unsigned sig_offset; + unsigned sig_len; + const struct section_header *secs; + + /* PKCS#7 MS Individual Code Signing content */ + const void *digest; /* Digest */ + unsigned digest_len; /* Digest length */ + const char *digest_algo; /* Digest algorithm */ +}; + +#define kenter(FMT, ...) \ + pr_devel("==> %s("FMT")\n", __func__, ##__VA_ARGS__) +#define kleave(FMT, ...) \ + pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__) + +/* + * mscode_parser.c + */ +extern int mscode_parse(void *_ctx, const void *content_data, size_t data_len, + size_t asn1hdrlen); diff --git a/crypto/asymmetric_keys/x509.asn1 b/crypto/asymmetric_keys/x509.asn1 new file mode 100644 index 000000000..92d59c32f --- /dev/null +++ b/crypto/asymmetric_keys/x509.asn1 @@ -0,0 +1,60 @@ +Certificate ::= SEQUENCE { + tbsCertificate TBSCertificate ({ x509_note_tbs_certificate }), + signatureAlgorithm AlgorithmIdentifier, + signature BIT STRING ({ x509_note_signature }) + } + +TBSCertificate ::= SEQUENCE { + version [ 0 ] Version DEFAULT, + serialNumber CertificateSerialNumber ({ x509_note_serial }), + signature AlgorithmIdentifier ({ x509_note_sig_algo }), + issuer Name ({ x509_note_issuer }), + validity Validity, + subject Name ({ x509_note_subject }), + subjectPublicKeyInfo SubjectPublicKeyInfo, + issuerUniqueID [ 1 ] IMPLICIT UniqueIdentifier OPTIONAL, + subjectUniqueID [ 2 ] IMPLICIT UniqueIdentifier OPTIONAL, + extensions [ 3 ] Extensions OPTIONAL + } + +Version ::= INTEGER +CertificateSerialNumber ::= INTEGER + +AlgorithmIdentifier ::= SEQUENCE { + algorithm OBJECT IDENTIFIER ({ x509_note_OID }), + parameters ANY OPTIONAL ({ x509_note_params }) +} + +Name ::= SEQUENCE OF RelativeDistinguishedName + +RelativeDistinguishedName ::= SET OF AttributeValueAssertion + +AttributeValueAssertion ::= SEQUENCE { + attributeType OBJECT IDENTIFIER ({ x509_note_OID }), + attributeValue ANY ({ x509_extract_name_segment }) + } + +Validity ::= SEQUENCE { + notBefore Time ({ x509_note_not_before }), + notAfter Time ({ x509_note_not_after }) + } + +Time ::= CHOICE { + utcTime UTCTime, + generalTime GeneralizedTime + } + +SubjectPublicKeyInfo ::= SEQUENCE { + algorithm AlgorithmIdentifier, + subjectPublicKey BIT STRING ({ x509_extract_key_data }) + } + +UniqueIdentifier ::= BIT STRING + +Extensions ::= SEQUENCE OF Extension + +Extension ::= SEQUENCE { + extnid OBJECT IDENTIFIER ({ x509_note_OID }), + critical BOOLEAN DEFAULT, + extnValue OCTET STRING ({ x509_process_extension }) + } diff --git a/crypto/asymmetric_keys/x509_akid.asn1 b/crypto/asymmetric_keys/x509_akid.asn1 new file mode 100644 index 000000000..1a33231a7 --- /dev/null +++ b/crypto/asymmetric_keys/x509_akid.asn1 @@ -0,0 +1,35 @@ +-- X.509 AuthorityKeyIdentifier +-- rfc5280 section 4.2.1.1 + +AuthorityKeyIdentifier ::= SEQUENCE { + keyIdentifier [0] IMPLICIT KeyIdentifier OPTIONAL, + authorityCertIssuer [1] IMPLICIT GeneralNames OPTIONAL, + authorityCertSerialNumber [2] IMPLICIT CertificateSerialNumber OPTIONAL + } + +KeyIdentifier ::= OCTET STRING ({ x509_akid_note_kid }) + +CertificateSerialNumber ::= INTEGER ({ x509_akid_note_serial }) + +GeneralNames ::= SEQUENCE OF GeneralName + +GeneralName ::= CHOICE { + otherName [0] ANY, + rfc822Name [1] IA5String, + dNSName [2] IA5String, + x400Address [3] ANY, + directoryName [4] Name ({ x509_akid_note_name }), + ediPartyName [5] ANY, + uniformResourceIdentifier [6] IA5String, + iPAddress [7] OCTET STRING, + registeredID [8] OBJECT IDENTIFIER + } + +Name ::= SEQUENCE OF RelativeDistinguishedName + +RelativeDistinguishedName ::= SET OF AttributeValueAssertion + +AttributeValueAssertion ::= SEQUENCE { + attributeType OBJECT IDENTIFIER ({ x509_note_OID }), + attributeValue ANY ({ x509_extract_name_segment }) + } diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c new file mode 100644 index 000000000..0a7049b47 --- /dev/null +++ b/crypto/asymmetric_keys/x509_cert_parser.c @@ -0,0 +1,817 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* X.509 certificate parser + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "X.509: "fmt +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/oid_registry.h> +#include <crypto/public_key.h> +#include "x509_parser.h" +#include "x509.asn1.h" +#include "x509_akid.asn1.h" + +struct x509_parse_context { + struct x509_certificate *cert; /* Certificate being constructed */ + unsigned long data; /* Start of data */ + const void *key; /* Key data */ + size_t key_size; /* Size of key data */ + const void *params; /* Key parameters */ + size_t params_size; /* Size of key parameters */ + enum OID key_algo; /* Algorithm used by the cert's key */ + enum OID last_oid; /* Last OID encountered */ + enum OID sig_algo; /* Algorithm used to sign the cert */ + u8 o_size; /* Size of organizationName (O) */ + u8 cn_size; /* Size of commonName (CN) */ + u8 email_size; /* Size of emailAddress */ + u16 o_offset; /* Offset of organizationName (O) */ + u16 cn_offset; /* Offset of commonName (CN) */ + u16 email_offset; /* Offset of emailAddress */ + unsigned raw_akid_size; + const void *raw_akid; /* Raw authorityKeyId in ASN.1 */ + const void *akid_raw_issuer; /* Raw directoryName in authorityKeyId */ + unsigned akid_raw_issuer_size; +}; + +/* + * Free an X.509 certificate + */ +void x509_free_certificate(struct x509_certificate *cert) +{ + if (cert) { + public_key_free(cert->pub); + public_key_signature_free(cert->sig); + kfree(cert->issuer); + kfree(cert->subject); + kfree(cert->id); + kfree(cert->skid); + kfree(cert); + } +} +EXPORT_SYMBOL_GPL(x509_free_certificate); + +/* + * Parse an X.509 certificate + */ +struct x509_certificate *x509_cert_parse(const void *data, size_t datalen) +{ + struct x509_certificate *cert; + struct x509_parse_context *ctx; + struct asymmetric_key_id *kid; + long ret; + + ret = -ENOMEM; + cert = kzalloc(sizeof(struct x509_certificate), GFP_KERNEL); + if (!cert) + goto error_no_cert; + cert->pub = kzalloc(sizeof(struct public_key), GFP_KERNEL); + if (!cert->pub) + goto error_no_ctx; + cert->sig = kzalloc(sizeof(struct public_key_signature), GFP_KERNEL); + if (!cert->sig) + goto error_no_ctx; + ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL); + if (!ctx) + goto error_no_ctx; + + ctx->cert = cert; + ctx->data = (unsigned long)data; + + /* Attempt to decode the certificate */ + ret = asn1_ber_decoder(&x509_decoder, ctx, data, datalen); + if (ret < 0) + goto error_decode; + + /* Decode the AuthorityKeyIdentifier */ + if (ctx->raw_akid) { + pr_devel("AKID: %u %*phN\n", + ctx->raw_akid_size, ctx->raw_akid_size, ctx->raw_akid); + ret = asn1_ber_decoder(&x509_akid_decoder, ctx, + ctx->raw_akid, ctx->raw_akid_size); + if (ret < 0) { + pr_warn("Couldn't decode AuthKeyIdentifier\n"); + goto error_decode; + } + } + + ret = -ENOMEM; + cert->pub->key = kmemdup(ctx->key, ctx->key_size, GFP_KERNEL); + if (!cert->pub->key) + goto error_decode; + + cert->pub->keylen = ctx->key_size; + + cert->pub->params = kmemdup(ctx->params, ctx->params_size, GFP_KERNEL); + if (!cert->pub->params) + goto error_decode; + + cert->pub->paramlen = ctx->params_size; + cert->pub->algo = ctx->key_algo; + + /* Grab the signature bits */ + ret = x509_get_sig_params(cert); + if (ret < 0) + goto error_decode; + + /* Generate cert issuer + serial number key ID */ + kid = asymmetric_key_generate_id(cert->raw_serial, + cert->raw_serial_size, + cert->raw_issuer, + cert->raw_issuer_size); + if (IS_ERR(kid)) { + ret = PTR_ERR(kid); + goto error_decode; + } + cert->id = kid; + + /* Detect self-signed certificates */ + ret = x509_check_for_self_signed(cert); + if (ret < 0) + goto error_decode; + + kfree(ctx); + return cert; + +error_decode: + kfree(ctx); +error_no_ctx: + x509_free_certificate(cert); +error_no_cert: + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(x509_cert_parse); + +/* + * Note an OID when we find one for later processing when we know how + * to interpret it. + */ +int x509_note_OID(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + ctx->last_oid = look_up_OID(value, vlen); + if (ctx->last_oid == OID__NR) { + char buffer[50]; + sprint_oid(value, vlen, buffer, sizeof(buffer)); + pr_debug("Unknown OID: [%lu] %s\n", + (unsigned long)value - ctx->data, buffer); + } + return 0; +} + +/* + * Save the position of the TBS data so that we can check the signature over it + * later. + */ +int x509_note_tbs_certificate(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + pr_debug("x509_note_tbs_certificate(,%zu,%02x,%ld,%zu)!\n", + hdrlen, tag, (unsigned long)value - ctx->data, vlen); + + ctx->cert->tbs = value - hdrlen; + ctx->cert->tbs_size = vlen + hdrlen; + return 0; +} + +/* + * Record the algorithm that was used to sign this certificate. + */ +int x509_note_sig_algo(void *context, size_t hdrlen, unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + pr_debug("PubKey Algo: %u\n", ctx->last_oid); + + switch (ctx->last_oid) { + case OID_md2WithRSAEncryption: + case OID_md3WithRSAEncryption: + default: + return -ENOPKG; /* Unsupported combination */ + + case OID_md4WithRSAEncryption: + ctx->cert->sig->hash_algo = "md4"; + goto rsa_pkcs1; + + case OID_sha1WithRSAEncryption: + ctx->cert->sig->hash_algo = "sha1"; + goto rsa_pkcs1; + + case OID_sha256WithRSAEncryption: + ctx->cert->sig->hash_algo = "sha256"; + goto rsa_pkcs1; + + case OID_sha384WithRSAEncryption: + ctx->cert->sig->hash_algo = "sha384"; + goto rsa_pkcs1; + + case OID_sha512WithRSAEncryption: + ctx->cert->sig->hash_algo = "sha512"; + goto rsa_pkcs1; + + case OID_sha224WithRSAEncryption: + ctx->cert->sig->hash_algo = "sha224"; + goto rsa_pkcs1; + + case OID_id_ecdsa_with_sha1: + ctx->cert->sig->hash_algo = "sha1"; + goto ecdsa; + + case OID_id_ecdsa_with_sha224: + ctx->cert->sig->hash_algo = "sha224"; + goto ecdsa; + + case OID_id_ecdsa_with_sha256: + ctx->cert->sig->hash_algo = "sha256"; + goto ecdsa; + + case OID_id_ecdsa_with_sha384: + ctx->cert->sig->hash_algo = "sha384"; + goto ecdsa; + + case OID_id_ecdsa_with_sha512: + ctx->cert->sig->hash_algo = "sha512"; + goto ecdsa; + + case OID_gost2012Signature256: + ctx->cert->sig->hash_algo = "streebog256"; + goto ecrdsa; + + case OID_gost2012Signature512: + ctx->cert->sig->hash_algo = "streebog512"; + goto ecrdsa; + + case OID_SM2_with_SM3: + ctx->cert->sig->hash_algo = "sm3"; + goto sm2; + } + +rsa_pkcs1: + ctx->cert->sig->pkey_algo = "rsa"; + ctx->cert->sig->encoding = "pkcs1"; + ctx->sig_algo = ctx->last_oid; + return 0; +ecrdsa: + ctx->cert->sig->pkey_algo = "ecrdsa"; + ctx->cert->sig->encoding = "raw"; + ctx->sig_algo = ctx->last_oid; + return 0; +sm2: + ctx->cert->sig->pkey_algo = "sm2"; + ctx->cert->sig->encoding = "raw"; + ctx->sig_algo = ctx->last_oid; + return 0; +ecdsa: + ctx->cert->sig->pkey_algo = "ecdsa"; + ctx->cert->sig->encoding = "x962"; + ctx->sig_algo = ctx->last_oid; + return 0; +} + +/* + * Note the whereabouts and type of the signature. + */ +int x509_note_signature(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + pr_debug("Signature: alg=%u, size=%zu\n", ctx->last_oid, vlen); + + /* + * In X.509 certificates, the signature's algorithm is stored in two + * places: inside the TBSCertificate (the data that is signed), and + * alongside the signature. These *must* match. + */ + if (ctx->last_oid != ctx->sig_algo) { + pr_warn("signatureAlgorithm (%u) differs from tbsCertificate.signature (%u)\n", + ctx->last_oid, ctx->sig_algo); + return -EINVAL; + } + + if (strcmp(ctx->cert->sig->pkey_algo, "rsa") == 0 || + strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0 || + strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0 || + strcmp(ctx->cert->sig->pkey_algo, "ecdsa") == 0) { + /* Discard the BIT STRING metadata */ + if (vlen < 1 || *(const u8 *)value != 0) + return -EBADMSG; + + value++; + vlen--; + } + + ctx->cert->raw_sig = value; + ctx->cert->raw_sig_size = vlen; + return 0; +} + +/* + * Note the certificate serial number + */ +int x509_note_serial(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + ctx->cert->raw_serial = value; + ctx->cert->raw_serial_size = vlen; + return 0; +} + +/* + * Note some of the name segments from which we'll fabricate a name. + */ +int x509_extract_name_segment(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + switch (ctx->last_oid) { + case OID_commonName: + ctx->cn_size = vlen; + ctx->cn_offset = (unsigned long)value - ctx->data; + break; + case OID_organizationName: + ctx->o_size = vlen; + ctx->o_offset = (unsigned long)value - ctx->data; + break; + case OID_email_address: + ctx->email_size = vlen; + ctx->email_offset = (unsigned long)value - ctx->data; + break; + default: + break; + } + + return 0; +} + +/* + * Fabricate and save the issuer and subject names + */ +static int x509_fabricate_name(struct x509_parse_context *ctx, size_t hdrlen, + unsigned char tag, + char **_name, size_t vlen) +{ + const void *name, *data = (const void *)ctx->data; + size_t namesize; + char *buffer; + + if (*_name) + return -EINVAL; + + /* Empty name string if no material */ + if (!ctx->cn_size && !ctx->o_size && !ctx->email_size) { + buffer = kmalloc(1, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + buffer[0] = 0; + goto done; + } + + if (ctx->cn_size && ctx->o_size) { + /* Consider combining O and CN, but use only the CN if it is + * prefixed by the O, or a significant portion thereof. + */ + namesize = ctx->cn_size; + name = data + ctx->cn_offset; + if (ctx->cn_size >= ctx->o_size && + memcmp(data + ctx->cn_offset, data + ctx->o_offset, + ctx->o_size) == 0) + goto single_component; + if (ctx->cn_size >= 7 && + ctx->o_size >= 7 && + memcmp(data + ctx->cn_offset, data + ctx->o_offset, 7) == 0) + goto single_component; + + buffer = kmalloc(ctx->o_size + 2 + ctx->cn_size + 1, + GFP_KERNEL); + if (!buffer) + return -ENOMEM; + + memcpy(buffer, + data + ctx->o_offset, ctx->o_size); + buffer[ctx->o_size + 0] = ':'; + buffer[ctx->o_size + 1] = ' '; + memcpy(buffer + ctx->o_size + 2, + data + ctx->cn_offset, ctx->cn_size); + buffer[ctx->o_size + 2 + ctx->cn_size] = 0; + goto done; + + } else if (ctx->cn_size) { + namesize = ctx->cn_size; + name = data + ctx->cn_offset; + } else if (ctx->o_size) { + namesize = ctx->o_size; + name = data + ctx->o_offset; + } else { + namesize = ctx->email_size; + name = data + ctx->email_offset; + } + +single_component: + buffer = kmalloc(namesize + 1, GFP_KERNEL); + if (!buffer) + return -ENOMEM; + memcpy(buffer, name, namesize); + buffer[namesize] = 0; + +done: + *_name = buffer; + ctx->cn_size = 0; + ctx->o_size = 0; + ctx->email_size = 0; + return 0; +} + +int x509_note_issuer(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + struct asymmetric_key_id *kid; + + ctx->cert->raw_issuer = value; + ctx->cert->raw_issuer_size = vlen; + + if (!ctx->cert->sig->auth_ids[2]) { + kid = asymmetric_key_generate_id(value, vlen, "", 0); + if (IS_ERR(kid)) + return PTR_ERR(kid); + ctx->cert->sig->auth_ids[2] = kid; + } + + return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->issuer, vlen); +} + +int x509_note_subject(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + ctx->cert->raw_subject = value; + ctx->cert->raw_subject_size = vlen; + return x509_fabricate_name(ctx, hdrlen, tag, &ctx->cert->subject, vlen); +} + +/* + * Extract the parameters for the public key + */ +int x509_note_params(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + /* + * AlgorithmIdentifier is used three times in the x509, we should skip + * first and ignore third, using second one which is after subject and + * before subjectPublicKey. + */ + if (!ctx->cert->raw_subject || ctx->key) + return 0; + ctx->params = value - hdrlen; + ctx->params_size = vlen + hdrlen; + return 0; +} + +/* + * Extract the data for the public key algorithm + */ +int x509_extract_key_data(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + enum OID oid; + + ctx->key_algo = ctx->last_oid; + switch (ctx->last_oid) { + case OID_rsaEncryption: + ctx->cert->pub->pkey_algo = "rsa"; + break; + case OID_gost2012PKey256: + case OID_gost2012PKey512: + ctx->cert->pub->pkey_algo = "ecrdsa"; + break; + case OID_sm2: + ctx->cert->pub->pkey_algo = "sm2"; + break; + case OID_id_ecPublicKey: + if (parse_OID(ctx->params, ctx->params_size, &oid) != 0) + return -EBADMSG; + + switch (oid) { + case OID_sm2: + ctx->cert->pub->pkey_algo = "sm2"; + break; + case OID_id_prime192v1: + ctx->cert->pub->pkey_algo = "ecdsa-nist-p192"; + break; + case OID_id_prime256v1: + ctx->cert->pub->pkey_algo = "ecdsa-nist-p256"; + break; + case OID_id_ansip384r1: + ctx->cert->pub->pkey_algo = "ecdsa-nist-p384"; + break; + default: + return -ENOPKG; + } + break; + default: + return -ENOPKG; + } + + /* Discard the BIT STRING metadata */ + if (vlen < 1 || *(const u8 *)value != 0) + return -EBADMSG; + ctx->key = value + 1; + ctx->key_size = vlen - 1; + return 0; +} + +/* The keyIdentifier in AuthorityKeyIdentifier SEQUENCE is tag(CONT,PRIM,0) */ +#define SEQ_TAG_KEYID (ASN1_CONT << 6) + +/* + * Process certificate extensions that are used to qualify the certificate. + */ +int x509_process_extension(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + struct asymmetric_key_id *kid; + const unsigned char *v = value; + + pr_debug("Extension: %u\n", ctx->last_oid); + + if (ctx->last_oid == OID_subjectKeyIdentifier) { + /* Get hold of the key fingerprint */ + if (ctx->cert->skid || vlen < 3) + return -EBADMSG; + if (v[0] != ASN1_OTS || v[1] != vlen - 2) + return -EBADMSG; + v += 2; + vlen -= 2; + + ctx->cert->raw_skid_size = vlen; + ctx->cert->raw_skid = v; + kid = asymmetric_key_generate_id(v, vlen, "", 0); + if (IS_ERR(kid)) + return PTR_ERR(kid); + ctx->cert->skid = kid; + pr_debug("subjkeyid %*phN\n", kid->len, kid->data); + return 0; + } + + if (ctx->last_oid == OID_keyUsage) { + /* + * Get hold of the keyUsage bit string + * v[1] is the encoding size + * (Expect either 0x02 or 0x03, making it 1 or 2 bytes) + * v[2] is the number of unused bits in the bit string + * (If >= 3 keyCertSign is missing when v[1] = 0x02) + * v[3] and possibly v[4] contain the bit string + * + * From RFC 5280 4.2.1.3: + * 0x04 is where keyCertSign lands in this bit string + * 0x80 is where digitalSignature lands in this bit string + */ + if (v[0] != ASN1_BTS) + return -EBADMSG; + if (vlen < 4) + return -EBADMSG; + if (v[2] >= 8) + return -EBADMSG; + if (v[3] & 0x80) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_DIGITALSIG; + if (v[1] == 0x02 && v[2] <= 2 && (v[3] & 0x04)) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN; + else if (vlen > 4 && v[1] == 0x03 && (v[3] & 0x04)) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_KEYCERTSIGN; + return 0; + } + + if (ctx->last_oid == OID_authorityKeyIdentifier) { + /* Get hold of the CA key fingerprint */ + ctx->raw_akid = v; + ctx->raw_akid_size = vlen; + return 0; + } + + if (ctx->last_oid == OID_basicConstraints) { + /* + * Get hold of the basicConstraints + * v[1] is the encoding size + * (Expect 0x2 or greater, making it 1 or more bytes) + * v[2] is the encoding type + * (Expect an ASN1_BOOL for the CA) + * v[3] is the contents of the ASN1_BOOL + * (Expect 1 if the CA is TRUE) + * vlen should match the entire extension size + */ + if (v[0] != (ASN1_CONS_BIT | ASN1_SEQ)) + return -EBADMSG; + if (vlen < 2) + return -EBADMSG; + if (v[1] != vlen - 2) + return -EBADMSG; + if (vlen >= 4 && v[1] != 0 && v[2] == ASN1_BOOL && v[3] == 1) + ctx->cert->pub->key_eflags |= 1 << KEY_EFLAG_CA; + return 0; + } + + return 0; +} + +/** + * x509_decode_time - Decode an X.509 time ASN.1 object + * @_t: The time to fill in + * @hdrlen: The length of the object header + * @tag: The object tag + * @value: The object value + * @vlen: The size of the object value + * + * Decode an ASN.1 universal time or generalised time field into a struct the + * kernel can handle and check it for validity. The time is decoded thus: + * + * [RFC5280 ยง4.1.2.5] + * CAs conforming to this profile MUST always encode certificate validity + * dates through the year 2049 as UTCTime; certificate validity dates in + * 2050 or later MUST be encoded as GeneralizedTime. Conforming + * applications MUST be able to process validity dates that are encoded in + * either UTCTime or GeneralizedTime. + */ +int x509_decode_time(time64_t *_t, size_t hdrlen, + unsigned char tag, + const unsigned char *value, size_t vlen) +{ + static const unsigned char month_lengths[] = { 31, 28, 31, 30, 31, 30, + 31, 31, 30, 31, 30, 31 }; + const unsigned char *p = value; + unsigned year, mon, day, hour, min, sec, mon_len; + +#define dec2bin(X) ({ unsigned char x = (X) - '0'; if (x > 9) goto invalid_time; x; }) +#define DD2bin(P) ({ unsigned x = dec2bin(P[0]) * 10 + dec2bin(P[1]); P += 2; x; }) + + if (tag == ASN1_UNITIM) { + /* UTCTime: YYMMDDHHMMSSZ */ + if (vlen != 13) + goto unsupported_time; + year = DD2bin(p); + if (year >= 50) + year += 1900; + else + year += 2000; + } else if (tag == ASN1_GENTIM) { + /* GenTime: YYYYMMDDHHMMSSZ */ + if (vlen != 15) + goto unsupported_time; + year = DD2bin(p) * 100 + DD2bin(p); + if (year >= 1950 && year <= 2049) + goto invalid_time; + } else { + goto unsupported_time; + } + + mon = DD2bin(p); + day = DD2bin(p); + hour = DD2bin(p); + min = DD2bin(p); + sec = DD2bin(p); + + if (*p != 'Z') + goto unsupported_time; + + if (year < 1970 || + mon < 1 || mon > 12) + goto invalid_time; + + mon_len = month_lengths[mon - 1]; + if (mon == 2) { + if (year % 4 == 0) { + mon_len = 29; + if (year % 100 == 0) { + mon_len = 28; + if (year % 400 == 0) + mon_len = 29; + } + } + } + + if (day < 1 || day > mon_len || + hour > 24 || /* ISO 8601 permits 24:00:00 as midnight tomorrow */ + min > 59 || + sec > 60) /* ISO 8601 permits leap seconds [X.680 46.3] */ + goto invalid_time; + + *_t = mktime64(year, mon, day, hour, min, sec); + return 0; + +unsupported_time: + pr_debug("Got unsupported time [tag %02x]: '%*phN'\n", + tag, (int)vlen, value); + return -EBADMSG; +invalid_time: + pr_debug("Got invalid time [tag %02x]: '%*phN'\n", + tag, (int)vlen, value); + return -EBADMSG; +} +EXPORT_SYMBOL_GPL(x509_decode_time); + +int x509_note_not_before(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + return x509_decode_time(&ctx->cert->valid_from, hdrlen, tag, value, vlen); +} + +int x509_note_not_after(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + return x509_decode_time(&ctx->cert->valid_to, hdrlen, tag, value, vlen); +} + +/* + * Note a key identifier-based AuthorityKeyIdentifier + */ +int x509_akid_note_kid(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + struct asymmetric_key_id *kid; + + pr_debug("AKID: keyid: %*phN\n", (int)vlen, value); + + if (ctx->cert->sig->auth_ids[1]) + return 0; + + kid = asymmetric_key_generate_id(value, vlen, "", 0); + if (IS_ERR(kid)) + return PTR_ERR(kid); + pr_debug("authkeyid %*phN\n", kid->len, kid->data); + ctx->cert->sig->auth_ids[1] = kid; + return 0; +} + +/* + * Note a directoryName in an AuthorityKeyIdentifier + */ +int x509_akid_note_name(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + + pr_debug("AKID: name: %*phN\n", (int)vlen, value); + + ctx->akid_raw_issuer = value; + ctx->akid_raw_issuer_size = vlen; + return 0; +} + +/* + * Note a serial number in an AuthorityKeyIdentifier + */ +int x509_akid_note_serial(void *context, size_t hdrlen, + unsigned char tag, + const void *value, size_t vlen) +{ + struct x509_parse_context *ctx = context; + struct asymmetric_key_id *kid; + + pr_debug("AKID: serial: %*phN\n", (int)vlen, value); + + if (!ctx->akid_raw_issuer || ctx->cert->sig->auth_ids[0]) + return 0; + + kid = asymmetric_key_generate_id(value, + vlen, + ctx->akid_raw_issuer, + ctx->akid_raw_issuer_size); + if (IS_ERR(kid)) + return PTR_ERR(kid); + + pr_debug("authkeyid %*phN\n", kid->len, kid->data); + ctx->cert->sig->auth_ids[0] = kid; + return 0; +} diff --git a/crypto/asymmetric_keys/x509_loader.c b/crypto/asymmetric_keys/x509_loader.c new file mode 100644 index 000000000..a41741326 --- /dev/null +++ b/crypto/asymmetric_keys/x509_loader.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/kernel.h> +#include <linux/key.h> +#include <keys/asymmetric-type.h> + +int x509_load_certificate_list(const u8 cert_list[], + const unsigned long list_size, + const struct key *keyring) +{ + key_ref_t key; + const u8 *p, *end; + size_t plen; + + p = cert_list; + end = p + list_size; + while (p < end) { + /* Each cert begins with an ASN.1 SEQUENCE tag and must be more + * than 256 bytes in size. + */ + if (end - p < 4) + goto dodgy_cert; + if (p[0] != 0x30 && + p[1] != 0x82) + goto dodgy_cert; + plen = (p[2] << 8) | p[3]; + plen += 4; + if (plen > end - p) + goto dodgy_cert; + + key = key_create_or_update(make_key_ref(keyring, 1), + "asymmetric", + NULL, + p, + plen, + ((KEY_POS_ALL & ~KEY_POS_SETATTR) | + KEY_USR_VIEW | KEY_USR_READ), + KEY_ALLOC_NOT_IN_QUOTA | + KEY_ALLOC_BUILT_IN | + KEY_ALLOC_BYPASS_RESTRICTION); + if (IS_ERR(key)) { + pr_err("Problem loading in-kernel X.509 certificate (%ld)\n", + PTR_ERR(key)); + } else { + pr_notice("Loaded X.509 cert '%s'\n", + key_ref_to_ptr(key)->description); + key_ref_put(key); + } + p += plen; + } + + return 0; + +dodgy_cert: + pr_err("Problem parsing in-kernel X.509 certificate list\n"); + return 0; +} +EXPORT_SYMBOL_GPL(x509_load_certificate_list); diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h new file mode 100644 index 000000000..97a886cbe --- /dev/null +++ b/crypto/asymmetric_keys/x509_parser.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* X.509 certificate parser internal definitions + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include <linux/time.h> +#include <crypto/public_key.h> +#include <keys/asymmetric-type.h> + +struct x509_certificate { + struct x509_certificate *next; + struct x509_certificate *signer; /* Certificate that signed this one */ + struct public_key *pub; /* Public key details */ + struct public_key_signature *sig; /* Signature parameters */ + char *issuer; /* Name of certificate issuer */ + char *subject; /* Name of certificate subject */ + struct asymmetric_key_id *id; /* Issuer + Serial number */ + struct asymmetric_key_id *skid; /* Subject + subjectKeyId (optional) */ + time64_t valid_from; + time64_t valid_to; + const void *tbs; /* Signed data */ + unsigned tbs_size; /* Size of signed data */ + unsigned raw_sig_size; /* Size of signature */ + const void *raw_sig; /* Signature data */ + const void *raw_serial; /* Raw serial number in ASN.1 */ + unsigned raw_serial_size; + unsigned raw_issuer_size; + const void *raw_issuer; /* Raw issuer name in ASN.1 */ + const void *raw_subject; /* Raw subject name in ASN.1 */ + unsigned raw_subject_size; + unsigned raw_skid_size; + const void *raw_skid; /* Raw subjectKeyId in ASN.1 */ + unsigned index; + bool seen; /* Infinite recursion prevention */ + bool verified; + bool self_signed; /* T if self-signed (check unsupported_sig too) */ + bool unsupported_sig; /* T if signature uses unsupported crypto */ + bool blacklisted; +}; + +/* + * x509_cert_parser.c + */ +extern void x509_free_certificate(struct x509_certificate *cert); +extern struct x509_certificate *x509_cert_parse(const void *data, size_t datalen); +extern int x509_decode_time(time64_t *_t, size_t hdrlen, + unsigned char tag, + const unsigned char *value, size_t vlen); + +/* + * x509_public_key.c + */ +extern int x509_get_sig_params(struct x509_certificate *cert); +extern int x509_check_for_self_signed(struct x509_certificate *cert); diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c new file mode 100644 index 000000000..6a4f00be2 --- /dev/null +++ b/crypto/asymmetric_keys/x509_public_key.c @@ -0,0 +1,280 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Instantiate a public key crypto key from an X.509 Certificate + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#define pr_fmt(fmt) "X.509: "fmt +#include <crypto/hash.h> +#include <crypto/sm2.h> +#include <keys/asymmetric-parser.h> +#include <keys/asymmetric-subtype.h> +#include <keys/system_keyring.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/string.h> +#include "asymmetric_keys.h" +#include "x509_parser.h" + +/* + * Set up the signature parameters in an X.509 certificate. This involves + * digesting the signed data and extracting the signature. + */ +int x509_get_sig_params(struct x509_certificate *cert) +{ + struct public_key_signature *sig = cert->sig; + struct crypto_shash *tfm; + struct shash_desc *desc; + size_t desc_size; + int ret; + + pr_devel("==>%s()\n", __func__); + + sig->s = kmemdup(cert->raw_sig, cert->raw_sig_size, GFP_KERNEL); + if (!sig->s) + return -ENOMEM; + + sig->s_size = cert->raw_sig_size; + + /* Allocate the hashing algorithm we're going to need and find out how + * big the hash operational data will be. + */ + tfm = crypto_alloc_shash(sig->hash_algo, 0, 0); + if (IS_ERR(tfm)) { + if (PTR_ERR(tfm) == -ENOENT) { + cert->unsupported_sig = true; + return 0; + } + return PTR_ERR(tfm); + } + + desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); + sig->digest_size = crypto_shash_digestsize(tfm); + + ret = -ENOMEM; + sig->digest = kmalloc(sig->digest_size, GFP_KERNEL); + if (!sig->digest) + goto error; + + desc = kzalloc(desc_size, GFP_KERNEL); + if (!desc) + goto error; + + desc->tfm = tfm; + + if (strcmp(cert->pub->pkey_algo, "sm2") == 0) { + ret = strcmp(sig->hash_algo, "sm3") != 0 ? -EINVAL : + crypto_shash_init(desc) ?: + sm2_compute_z_digest(desc, cert->pub->key, + cert->pub->keylen, sig->digest) ?: + crypto_shash_init(desc) ?: + crypto_shash_update(desc, sig->digest, + sig->digest_size) ?: + crypto_shash_finup(desc, cert->tbs, cert->tbs_size, + sig->digest); + } else { + ret = crypto_shash_digest(desc, cert->tbs, cert->tbs_size, + sig->digest); + } + + if (ret < 0) + goto error_2; + + ret = is_hash_blacklisted(sig->digest, sig->digest_size, + BLACKLIST_HASH_X509_TBS); + if (ret == -EKEYREJECTED) { + pr_err("Cert %*phN is blacklisted\n", + sig->digest_size, sig->digest); + cert->blacklisted = true; + ret = 0; + } + +error_2: + kfree(desc); +error: + crypto_free_shash(tfm); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} + +/* + * Check for self-signedness in an X.509 cert and if found, check the signature + * immediately if we can. + */ +int x509_check_for_self_signed(struct x509_certificate *cert) +{ + int ret = 0; + + pr_devel("==>%s()\n", __func__); + + if (cert->raw_subject_size != cert->raw_issuer_size || + memcmp(cert->raw_subject, cert->raw_issuer, + cert->raw_issuer_size) != 0) + goto not_self_signed; + + if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) { + /* If the AKID is present it may have one or two parts. If + * both are supplied, both must match. + */ + bool a = asymmetric_key_id_same(cert->skid, cert->sig->auth_ids[1]); + bool b = asymmetric_key_id_same(cert->id, cert->sig->auth_ids[0]); + + if (!a && !b) + goto not_self_signed; + + ret = -EKEYREJECTED; + if (((a && !b) || (b && !a)) && + cert->sig->auth_ids[0] && cert->sig->auth_ids[1]) + goto out; + } + + if (cert->unsupported_sig) { + ret = 0; + goto out; + } + + ret = public_key_verify_signature(cert->pub, cert->sig); + if (ret < 0) { + if (ret == -ENOPKG) { + cert->unsupported_sig = true; + ret = 0; + } + goto out; + } + + pr_devel("Cert Self-signature verified"); + cert->self_signed = true; + +out: + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; + +not_self_signed: + pr_devel("<==%s() = 0 [not]\n", __func__); + return 0; +} + +/* + * Attempt to parse a data blob for a key as an X509 certificate. + */ +static int x509_key_preparse(struct key_preparsed_payload *prep) +{ + struct asymmetric_key_ids *kids; + struct x509_certificate *cert; + const char *q; + size_t srlen, sulen; + char *desc = NULL, *p; + int ret; + + cert = x509_cert_parse(prep->data, prep->datalen); + if (IS_ERR(cert)) + return PTR_ERR(cert); + + pr_devel("Cert Issuer: %s\n", cert->issuer); + pr_devel("Cert Subject: %s\n", cert->subject); + pr_devel("Cert Key Algo: %s\n", cert->pub->pkey_algo); + pr_devel("Cert Valid period: %lld-%lld\n", cert->valid_from, cert->valid_to); + + cert->pub->id_type = "X509"; + + if (cert->unsupported_sig) { + public_key_signature_free(cert->sig); + cert->sig = NULL; + } else { + pr_devel("Cert Signature: %s + %s\n", + cert->sig->pkey_algo, cert->sig->hash_algo); + } + + /* Don't permit addition of blacklisted keys */ + ret = -EKEYREJECTED; + if (cert->blacklisted) + goto error_free_cert; + + /* Propose a description */ + sulen = strlen(cert->subject); + if (cert->raw_skid) { + srlen = cert->raw_skid_size; + q = cert->raw_skid; + } else { + srlen = cert->raw_serial_size; + q = cert->raw_serial; + } + + ret = -ENOMEM; + desc = kmalloc(sulen + 2 + srlen * 2 + 1, GFP_KERNEL); + if (!desc) + goto error_free_cert; + p = memcpy(desc, cert->subject, sulen); + p += sulen; + *p++ = ':'; + *p++ = ' '; + p = bin2hex(p, q, srlen); + *p = 0; + + kids = kmalloc(sizeof(struct asymmetric_key_ids), GFP_KERNEL); + if (!kids) + goto error_free_desc; + kids->id[0] = cert->id; + kids->id[1] = cert->skid; + kids->id[2] = asymmetric_key_generate_id(cert->raw_subject, + cert->raw_subject_size, + "", 0); + if (IS_ERR(kids->id[2])) { + ret = PTR_ERR(kids->id[2]); + goto error_free_kids; + } + + /* We're pinning the module by being linked against it */ + __module_get(public_key_subtype.owner); + prep->payload.data[asym_subtype] = &public_key_subtype; + prep->payload.data[asym_key_ids] = kids; + prep->payload.data[asym_crypto] = cert->pub; + prep->payload.data[asym_auth] = cert->sig; + prep->description = desc; + prep->quotalen = 100; + + /* We've finished with the certificate */ + cert->pub = NULL; + cert->id = NULL; + cert->skid = NULL; + cert->sig = NULL; + desc = NULL; + kids = NULL; + ret = 0; + +error_free_kids: + kfree(kids); +error_free_desc: + kfree(desc); +error_free_cert: + x509_free_certificate(cert); + return ret; +} + +static struct asymmetric_key_parser x509_key_parser = { + .owner = THIS_MODULE, + .name = "x509", + .parse = x509_key_preparse, +}; + +/* + * Module stuff + */ +static int __init x509_key_init(void) +{ + return register_asymmetric_key_parser(&x509_key_parser); +} + +static void __exit x509_key_exit(void) +{ + unregister_asymmetric_key_parser(&x509_key_parser); +} + +module_init(x509_key_init); +module_exit(x509_key_exit); + +MODULE_DESCRIPTION("X.509 certificate parser"); +MODULE_AUTHOR("Red Hat, Inc."); +MODULE_LICENSE("GPL"); |