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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /crypto/asymmetric_keys/public_key.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--crypto/asymmetric_keys/public_key.c417
1 files changed, 417 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
new file mode 100644
index 000000000..bd713a214
--- /dev/null
+++ b/crypto/asymmetric_keys/public_key.c
@@ -0,0 +1,417 @@
+// 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 <linux/module.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/scatterlist.h>
+#include <keys/asymmetric-subtype.h>
+#include <crypto/public_key.h>
+#include <crypto/akcipher.h>
+#include <crypto/sm2.h>
+#include <crypto/sm3_base.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(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);
+}
+
+/*
+ * Determine the crypto algorithm name.
+ */
+static
+int software_key_determine_akcipher(const char *encoding,
+ const char *hash_algo,
+ const struct public_key *pkey,
+ char alg_name[CRYPTO_MAX_ALG_NAME])
+{
+ int n;
+
+ if (strcmp(encoding, "pkcs1") == 0) {
+ /* The data wangled by the RSA algorithm is typically padded
+ * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
+ * sec 8.2].
+ */
+ 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) {
+ strcpy(alg_name, pkey->pkey_algo);
+ return 0;
+ }
+
+ return -ENOPKG;
+}
+
+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];
+ u8 *key, *ptr;
+ int ret, len;
+
+ ret = software_key_determine_akcipher(params->encoding,
+ params->hash_algo,
+ pkey, alg_name);
+ if (ret < 0)
+ return ret;
+
+ tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ ret = -ENOMEM;
+ key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
+ GFP_KERNEL);
+ if (!key)
+ 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_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_key;
+
+ len = crypto_akcipher_maxsize(tfm);
+ info->key_size = len * 8;
+ info->max_data_size = len;
+ info->max_sig_size = len;
+ info->max_enc_size = len;
+ info->max_dec_size = len;
+ info->supported_ops = (KEYCTL_SUPPORTS_ENCRYPT |
+ KEYCTL_SUPPORTS_VERIFY);
+ if (pkey->key_is_private)
+ info->supported_ops |= (KEYCTL_SUPPORTS_DECRYPT |
+ KEYCTL_SUPPORTS_SIGN);
+ ret = 0;
+
+error_free_key:
+ kfree(key);
+error_free_tfm:
+ crypto_free_akcipher(tfm);
+ 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];
+ struct akcipher_request *req;
+ struct crypto_akcipher *tfm;
+ struct crypto_wait cwait;
+ struct scatterlist in_sg, out_sg;
+ char alg_name[CRYPTO_MAX_ALG_NAME];
+ char *key, *ptr;
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ ret = software_key_determine_akcipher(params->encoding,
+ params->hash_algo,
+ pkey, alg_name);
+ if (ret < 0)
+ return ret;
+
+ tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ ret = -ENOMEM;
+ req = akcipher_request_alloc(tfm, GFP_KERNEL);
+ if (!req)
+ goto error_free_tfm;
+
+ key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
+ GFP_KERNEL);
+ if (!key)
+ goto error_free_req;
+
+ 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_akcipher_set_priv_key(tfm, key, pkey->keylen);
+ else
+ ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
+ if (ret)
+ goto error_free_key;
+
+ sg_init_one(&in_sg, in, params->in_len);
+ sg_init_one(&out_sg, out, params->out_len);
+ akcipher_request_set_crypt(req, &in_sg, &out_sg, params->in_len,
+ params->out_len);
+ crypto_init_wait(&cwait);
+ akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+ CRYPTO_TFM_REQ_MAY_SLEEP,
+ crypto_req_done, &cwait);
+
+ /* Perform the encryption calculation. */
+ switch (params->op) {
+ case kernel_pkey_encrypt:
+ ret = crypto_akcipher_encrypt(req);
+ break;
+ case kernel_pkey_decrypt:
+ ret = crypto_akcipher_decrypt(req);
+ break;
+ case kernel_pkey_sign:
+ ret = crypto_akcipher_sign(req);
+ break;
+ default:
+ BUG();
+ }
+
+ ret = crypto_wait_req(ret, &cwait);
+ if (ret == 0)
+ ret = req->dst_len;
+
+error_free_key:
+ kfree(key);
+error_free_req:
+ akcipher_request_free(req);
+error_free_tfm:
+ crypto_free_akcipher(tfm);
+ pr_devel("<==%s() = %d\n", __func__, ret);
+ return ret;
+}
+
+#if IS_REACHABLE(CONFIG_CRYPTO_SM2)
+static int cert_sig_digest_update(const struct public_key_signature *sig,
+ struct crypto_akcipher *tfm_pkey)
+{
+ struct crypto_shash *tfm;
+ struct shash_desc *desc;
+ size_t desc_size;
+ unsigned char dgst[SM3_DIGEST_SIZE];
+ int ret;
+
+ BUG_ON(!sig->data);
+
+ /* SM2 signatures always use the SM3 hash algorithm */
+ if (!sig->hash_algo || strcmp(sig->hash_algo, "sm3") != 0)
+ return -EINVAL;
+
+ ret = sm2_compute_z_digest(tfm_pkey, SM2_DEFAULT_USERID,
+ SM2_DEFAULT_USERID_LEN, dgst);
+ if (ret)
+ return ret;
+
+ tfm = crypto_alloc_shash(sig->hash_algo, 0, 0);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
+ desc = kzalloc(desc_size, GFP_KERNEL);
+ if (!desc) {
+ ret = -ENOMEM;
+ goto error_free_tfm;
+ }
+
+ desc->tfm = tfm;
+
+ ret = crypto_shash_init(desc);
+ if (ret < 0)
+ goto error_free_desc;
+
+ ret = crypto_shash_update(desc, dgst, SM3_DIGEST_SIZE);
+ if (ret < 0)
+ goto error_free_desc;
+
+ ret = crypto_shash_finup(desc, sig->data, sig->data_size, sig->digest);
+
+error_free_desc:
+ kfree(desc);
+error_free_tfm:
+ crypto_free_shash(tfm);
+ return ret;
+}
+#else
+static inline int cert_sig_digest_update(
+ const struct public_key_signature *sig,
+ struct crypto_akcipher *tfm_pkey)
+{
+ return -ENOTSUPP;
+}
+#endif /* ! IS_REACHABLE(CONFIG_CRYPTO_SM2) */
+
+/*
+ * Verify a signature using a public key.
+ */
+int public_key_verify_signature(const struct public_key *pkey,
+ const struct public_key_signature *sig)
+{
+ struct crypto_wait cwait;
+ struct crypto_akcipher *tfm;
+ struct akcipher_request *req;
+ struct scatterlist src_sg;
+ char alg_name[CRYPTO_MAX_ALG_NAME];
+ char *buf, *ptr;
+ size_t buf_len;
+ int ret;
+
+ pr_devel("==>%s()\n", __func__);
+
+ BUG_ON(!pkey);
+ BUG_ON(!sig);
+ BUG_ON(!sig->s);
+
+ ret = software_key_determine_akcipher(sig->encoding,
+ sig->hash_algo,
+ pkey, alg_name);
+ if (ret < 0)
+ return ret;
+
+ tfm = crypto_alloc_akcipher(alg_name, 0, 0);
+ if (IS_ERR(tfm))
+ return PTR_ERR(tfm);
+
+ ret = -ENOMEM;
+ req = akcipher_request_alloc(tfm, GFP_KERNEL);
+ if (!req)
+ goto error_free_tfm;
+
+ buf_len = max_t(size_t, pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
+ sig->s_size + sig->digest_size);
+
+ buf = kmalloc(buf_len, GFP_KERNEL);
+ if (!buf)
+ goto error_free_req;
+
+ memcpy(buf, pkey->key, pkey->keylen);
+ ptr = buf + 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_akcipher_set_priv_key(tfm, buf, pkey->keylen);
+ else
+ ret = crypto_akcipher_set_pub_key(tfm, buf, pkey->keylen);
+ if (ret)
+ goto error_free_buf;
+
+ if (strcmp(pkey->pkey_algo, "sm2") == 0 && sig->data_size) {
+ ret = cert_sig_digest_update(sig, tfm);
+ if (ret)
+ goto error_free_buf;
+ }
+
+ memcpy(buf, sig->s, sig->s_size);
+ memcpy(buf + sig->s_size, sig->digest, sig->digest_size);
+
+ sg_init_one(&src_sg, buf, sig->s_size + sig->digest_size);
+ akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size,
+ sig->digest_size);
+ crypto_init_wait(&cwait);
+ akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
+ CRYPTO_TFM_REQ_MAY_SLEEP,
+ crypto_req_done, &cwait);
+ ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
+
+error_free_buf:
+ kfree(buf);
+error_free_req:
+ akcipher_request_free(req);
+error_free_tfm:
+ crypto_free_akcipher(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);