diff options
Diffstat (limited to '')
-rw-r--r-- | lib/crypto_backend/crypto_openssl.c | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/lib/crypto_backend/crypto_openssl.c b/lib/crypto_backend/crypto_openssl.c new file mode 100644 index 0000000..8681aab --- /dev/null +++ b/lib/crypto_backend/crypto_openssl.c @@ -0,0 +1,576 @@ +/* + * OPENSSL crypto backend implementation + * + * Copyright (C) 2010-2021 Red Hat, Inc. All rights reserved. + * Copyright (C) 2010-2021 Milan Broz + * + * This file is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This file is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this file; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + * In addition, as a special exception, the copyright holders give + * permission to link the code of portions of this program with the + * OpenSSL library under certain conditions as described in each + * individual source file, and distribute linked combinations + * including the two. + * + * You must obey the GNU Lesser General Public License in all respects + * for all of the code used other than OpenSSL. + */ + +#include <string.h> +#include <errno.h> +#include <openssl/evp.h> +#include <openssl/hmac.h> +#include <openssl/rand.h> +#include "crypto_backend_internal.h" + +#define CONST_CAST(x) (x)(uintptr_t) + +static int crypto_backend_initialised = 0; + +struct crypt_hash { + EVP_MD_CTX *md; + const EVP_MD *hash_id; + int hash_len; +}; + +struct crypt_hmac { + HMAC_CTX *md; + const EVP_MD *hash_id; + int hash_len; +}; + +struct crypt_cipher { + bool use_kernel; + union { + struct crypt_cipher_kernel kernel; + struct { + EVP_CIPHER_CTX *hd_enc; + EVP_CIPHER_CTX *hd_dec; + size_t iv_length; + } lib; + } u; +}; + +struct hash_alg { + const char *name; + const char *openssl_name; +}; + +/* + * Compatible wrappers for OpenSSL < 1.1.0 and LibreSSL < 2.7.0 + */ +#if OPENSSL_VERSION_NUMBER < 0x10100000L || \ + (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x2070000fL) + +static void openssl_backend_init(void) +{ + OpenSSL_add_all_algorithms(); +} + +static const char *openssl_backend_version(void) +{ + return SSLeay_version(SSLEAY_VERSION); +} + +static EVP_MD_CTX *EVP_MD_CTX_new(void) +{ + EVP_MD_CTX *md = malloc(sizeof(*md)); + + if (md) + EVP_MD_CTX_init(md); + + return md; +} + +static void EVP_MD_CTX_free(EVP_MD_CTX *md) +{ + EVP_MD_CTX_cleanup(md); + free(md); +} + +static HMAC_CTX *HMAC_CTX_new(void) +{ + HMAC_CTX *md = malloc(sizeof(*md)); + + if (md) + HMAC_CTX_init(md); + + return md; +} + +static void HMAC_CTX_free(HMAC_CTX *md) +{ + HMAC_CTX_cleanup(md); + free(md); +} +#else +static void openssl_backend_init(void) +{ +} + +static const char *openssl_backend_version(void) +{ + return OpenSSL_version(OPENSSL_VERSION); +} +#endif + +int crypt_backend_init(void) +{ + if (crypto_backend_initialised) + return 0; + + openssl_backend_init(); + + crypto_backend_initialised = 1; + return 0; +} + +void crypt_backend_destroy(void) +{ + crypto_backend_initialised = 0; +} + +uint32_t crypt_backend_flags(void) +{ + return 0; +} + +const char *crypt_backend_version(void) +{ + return openssl_backend_version(); +} + +static const char *crypt_hash_compat_name(const char *name) +{ + const char *hash_name = name; + int i; + static struct hash_alg hash_algs[] = { + { "blake2b-512", "blake2b512" }, + { "blake2s-256", "blake2s256" }, + { NULL, NULL, }}; + + if (!name) + return NULL; + + i = 0; + while (hash_algs[i].name) { + if (!strcasecmp(name, hash_algs[i].name)) { + hash_name = hash_algs[i].openssl_name; + break; + } + i++; + } + + return hash_name; +} + +/* HASH */ +int crypt_hash_size(const char *name) +{ + const EVP_MD *hash_id; + + hash_id = EVP_get_digestbyname(crypt_hash_compat_name(name)); + if (!hash_id) + return -EINVAL; + + return EVP_MD_size(hash_id); +} + +int crypt_hash_init(struct crypt_hash **ctx, const char *name) +{ + struct crypt_hash *h; + + h = malloc(sizeof(*h)); + if (!h) + return -ENOMEM; + + h->md = EVP_MD_CTX_new(); + if (!h->md) { + free(h); + return -ENOMEM; + } + + h->hash_id = EVP_get_digestbyname(crypt_hash_compat_name(name)); + if (!h->hash_id) { + EVP_MD_CTX_free(h->md); + free(h); + return -EINVAL; + } + + if (EVP_DigestInit_ex(h->md, h->hash_id, NULL) != 1) { + EVP_MD_CTX_free(h->md); + free(h); + return -EINVAL; + } + + h->hash_len = EVP_MD_size(h->hash_id); + *ctx = h; + return 0; +} + +static int crypt_hash_restart(struct crypt_hash *ctx) +{ + if (EVP_DigestInit_ex(ctx->md, ctx->hash_id, NULL) != 1) + return -EINVAL; + + return 0; +} + +int crypt_hash_write(struct crypt_hash *ctx, const char *buffer, size_t length) +{ + if (EVP_DigestUpdate(ctx->md, buffer, length) != 1) + return -EINVAL; + + return 0; +} + +int crypt_hash_final(struct crypt_hash *ctx, char *buffer, size_t length) +{ + unsigned char tmp[EVP_MAX_MD_SIZE]; + unsigned int tmp_len = 0; + + if (length > (size_t)ctx->hash_len) + return -EINVAL; + + if (EVP_DigestFinal_ex(ctx->md, tmp, &tmp_len) != 1) + return -EINVAL; + + memcpy(buffer, tmp, length); + crypt_backend_memzero(tmp, sizeof(tmp)); + + if (tmp_len < length) + return -EINVAL; + + if (crypt_hash_restart(ctx)) + return -EINVAL; + + return 0; +} + +void crypt_hash_destroy(struct crypt_hash *ctx) +{ + EVP_MD_CTX_free(ctx->md); + memset(ctx, 0, sizeof(*ctx)); + free(ctx); +} + +/* HMAC */ +int crypt_hmac_size(const char *name) +{ + return crypt_hash_size(name); +} + +int crypt_hmac_init(struct crypt_hmac **ctx, const char *name, + const void *key, size_t key_length) +{ + struct crypt_hmac *h; + + h = malloc(sizeof(*h)); + if (!h) + return -ENOMEM; + + h->md = HMAC_CTX_new(); + if (!h->md) { + free(h); + return -ENOMEM; + } + + h->hash_id = EVP_get_digestbyname(crypt_hash_compat_name(name)); + if (!h->hash_id) { + HMAC_CTX_free(h->md); + free(h); + return -EINVAL; + } + + HMAC_Init_ex(h->md, key, key_length, h->hash_id, NULL); + + h->hash_len = EVP_MD_size(h->hash_id); + *ctx = h; + return 0; +} + +static void crypt_hmac_restart(struct crypt_hmac *ctx) +{ + HMAC_Init_ex(ctx->md, NULL, 0, ctx->hash_id, NULL); +} + +int crypt_hmac_write(struct crypt_hmac *ctx, const char *buffer, size_t length) +{ + HMAC_Update(ctx->md, (const unsigned char *)buffer, length); + return 0; +} + +int crypt_hmac_final(struct crypt_hmac *ctx, char *buffer, size_t length) +{ + unsigned char tmp[EVP_MAX_MD_SIZE]; + unsigned int tmp_len = 0; + + if (length > (size_t)ctx->hash_len) + return -EINVAL; + + HMAC_Final(ctx->md, tmp, &tmp_len); + + memcpy(buffer, tmp, length); + crypt_backend_memzero(tmp, sizeof(tmp)); + + if (tmp_len < length) + return -EINVAL; + + crypt_hmac_restart(ctx); + + return 0; +} + +void crypt_hmac_destroy(struct crypt_hmac *ctx) +{ + HMAC_CTX_free(ctx->md); + memset(ctx, 0, sizeof(*ctx)); + free(ctx); +} + +/* RNG */ +int crypt_backend_rng(char *buffer, size_t length, int quality, int fips) +{ + if (RAND_bytes((unsigned char *)buffer, length) != 1) + return -EINVAL; + + return 0; +} + +/* PBKDF */ +int crypt_pbkdf(const char *kdf, const char *hash, + const char *password, size_t password_length, + const char *salt, size_t salt_length, + char *key, size_t key_length, + uint32_t iterations, uint32_t memory, uint32_t parallel) + +{ + const EVP_MD *hash_id; + + if (!kdf) + return -EINVAL; + + if (!strcmp(kdf, "pbkdf2")) { + hash_id = EVP_get_digestbyname(crypt_hash_compat_name(hash)); + if (!hash_id) + return -EINVAL; + + if (!PKCS5_PBKDF2_HMAC(password, (int)password_length, + (const unsigned char *)salt, (int)salt_length, + (int)iterations, hash_id, (int)key_length, (unsigned char *)key)) + return -EINVAL; + return 0; + } else if (!strncmp(kdf, "argon2", 6)) { + return argon2(kdf, password, password_length, salt, salt_length, + key, key_length, iterations, memory, parallel); + } + + return -EINVAL; +} + +/* Block ciphers */ +static void _cipher_destroy(EVP_CIPHER_CTX **hd_enc, EVP_CIPHER_CTX **hd_dec) +{ + EVP_CIPHER_CTX_free(*hd_enc); + *hd_enc = NULL; + + EVP_CIPHER_CTX_free(*hd_dec); + *hd_dec = NULL; +} + +static int _cipher_init(EVP_CIPHER_CTX **hd_enc, EVP_CIPHER_CTX **hd_dec, const char *name, + const char *mode, const void *key, size_t key_length, size_t *iv_length) +{ + char cipher_name[256]; + const EVP_CIPHER *type; + int r, key_bits; + + key_bits = key_length * 8; + if (!strcmp(mode, "xts")) + key_bits /= 2; + + r = snprintf(cipher_name, sizeof(cipher_name), "%s-%d-%s", name, key_bits, mode); + if (r < 0 || (size_t)r >= sizeof(cipher_name)) + return -EINVAL; + + type = EVP_get_cipherbyname(cipher_name); + if (!type) + return -ENOENT; + + if (EVP_CIPHER_key_length(type) != (int)key_length) + return -EINVAL; + + *hd_enc = EVP_CIPHER_CTX_new(); + *hd_dec = EVP_CIPHER_CTX_new(); + *iv_length = EVP_CIPHER_iv_length(type); + + if (!*hd_enc || !*hd_dec) + return -EINVAL; + + if (EVP_EncryptInit_ex(*hd_enc, type, NULL, key, NULL) != 1 || + EVP_DecryptInit_ex(*hd_dec, type, NULL, key, NULL) != 1) { + _cipher_destroy(hd_enc, hd_dec); + return -EINVAL; + } + + if (EVP_CIPHER_CTX_set_padding(*hd_enc, 0) != 1 || + EVP_CIPHER_CTX_set_padding(*hd_dec, 0) != 1) { + _cipher_destroy(hd_enc, hd_dec); + return -EINVAL; + } + + return 0; +} + +int crypt_cipher_init(struct crypt_cipher **ctx, const char *name, + const char *mode, const void *key, size_t key_length) +{ + struct crypt_cipher *h; + int r; + + h = malloc(sizeof(*h)); + if (!h) + return -ENOMEM; + + if (!_cipher_init(&h->u.lib.hd_enc, &h->u.lib.hd_dec, name, mode, key, + key_length, &h->u.lib.iv_length)) { + h->use_kernel = false; + *ctx = h; + return 0; + } + + r = crypt_cipher_init_kernel(&h->u.kernel, name, mode, key, key_length); + if (r < 0) { + free(h); + return r; + } + + h->use_kernel = true; + *ctx = h; + return 0; +} + +void crypt_cipher_destroy(struct crypt_cipher *ctx) +{ + if (ctx->use_kernel) + crypt_cipher_destroy_kernel(&ctx->u.kernel); + else + _cipher_destroy(&ctx->u.lib.hd_enc, &ctx->u.lib.hd_dec); + free(ctx); +} + +static int _cipher_encrypt(struct crypt_cipher *ctx, const unsigned char *in, unsigned char *out, + int length, const unsigned char *iv, size_t iv_length) +{ + int len; + + if (ctx->u.lib.iv_length != iv_length) + return -EINVAL; + + if (EVP_EncryptInit_ex(ctx->u.lib.hd_enc, NULL, NULL, NULL, iv) != 1) + return -EINVAL; + + if (EVP_EncryptUpdate(ctx->u.lib.hd_enc, out, &len, in, length) != 1) + return -EINVAL; + + if (EVP_EncryptFinal(ctx->u.lib.hd_enc, out + len, &len) != 1) + return -EINVAL; + + return 0; +} + +static int _cipher_decrypt(struct crypt_cipher *ctx, const unsigned char *in, unsigned char *out, + int length, const unsigned char *iv, size_t iv_length) +{ + int len; + + if (ctx->u.lib.iv_length != iv_length) + return -EINVAL; + + if (EVP_DecryptInit_ex(ctx->u.lib.hd_dec, NULL, NULL, NULL, iv) != 1) + return -EINVAL; + + if (EVP_DecryptUpdate(ctx->u.lib.hd_dec, out, &len, in, length) != 1) + return -EINVAL; + + if (EVP_DecryptFinal(ctx->u.lib.hd_dec, out + len, &len) != 1) + return -EINVAL; + + return 0; +} + +int crypt_cipher_encrypt(struct crypt_cipher *ctx, + const char *in, char *out, size_t length, + const char *iv, size_t iv_length) +{ + if (ctx->use_kernel) + return crypt_cipher_encrypt_kernel(&ctx->u.kernel, in, out, length, iv, iv_length); + + return _cipher_encrypt(ctx, (const unsigned char*)in, + (unsigned char *)out, length, (const unsigned char*)iv, iv_length); +} + +int crypt_cipher_decrypt(struct crypt_cipher *ctx, + const char *in, char *out, size_t length, + const char *iv, size_t iv_length) +{ + if (ctx->use_kernel) + return crypt_cipher_decrypt_kernel(&ctx->u.kernel, in, out, length, iv, iv_length); + + return _cipher_decrypt(ctx, (const unsigned char*)in, + (unsigned char *)out, length, (const unsigned char*)iv, iv_length); +} + +bool crypt_cipher_kernel_only(struct crypt_cipher *ctx) +{ + return ctx->use_kernel; +} + +int crypt_bitlk_decrypt_key(const void *key, size_t key_length, + const char *in, char *out, size_t length, + const char *iv, size_t iv_length, + const char *tag, size_t tag_length) +{ +#ifdef EVP_CTRL_CCM_SET_IVLEN + EVP_CIPHER_CTX *ctx; + int len = 0, r = -EINVAL; + + ctx = EVP_CIPHER_CTX_new(); + if (!ctx) + return -EINVAL; + + if (EVP_DecryptInit_ex(ctx, EVP_aes_256_ccm(), NULL, NULL, NULL) != 1) + goto out; + + //EVP_CIPHER_CTX_key_length(ctx) + //EVP_CIPHER_CTX_iv_length(ctx) + + if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_IVLEN, iv_length, NULL) != 1) + goto out; + if (EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_TAG, tag_length, CONST_CAST(void*)tag) != 1) + goto out; + + if (EVP_DecryptInit_ex(ctx, NULL, NULL, key, (const unsigned char*)iv) != 1) + goto out; + + if (EVP_DecryptUpdate(ctx, (unsigned char*)out, &len, (const unsigned char*)in, length) == 1) + r = 0; +out: + EVP_CIPHER_CTX_free(ctx); + return r; +#else + return -ENOTSUP; +#endif +} |