| /* |
| * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved. |
| * |
| * Licensed under the OpenSSL license (the "License"). You may not use |
| * this file except in compliance with the License. You can obtain a copy |
| * in the file LICENSE in the source distribution or at |
| * https://www.openssl.org/source/license.html |
| */ |
| |
| #include <stdio.h> |
| #include "internal/cryptlib.h" |
| #include <openssl/kdf.h> |
| #include <openssl/evp.h> |
| #include "crypto/evp.h" |
| |
| static int tls1_prf_alg(const EVP_MD *md, |
| const unsigned char *sec, size_t slen, |
| const unsigned char *seed, size_t seed_len, |
| unsigned char *out, size_t olen); |
| |
| #define TLS1_PRF_MAXBUF 1024 |
| |
| /* TLS KDF pkey context structure */ |
| |
| typedef struct { |
| /* Digest to use for PRF */ |
| const EVP_MD *md; |
| /* Secret value to use for PRF */ |
| unsigned char *sec; |
| size_t seclen; |
| /* Buffer of concatenated seed data */ |
| unsigned char seed[TLS1_PRF_MAXBUF]; |
| size_t seedlen; |
| } TLS1_PRF_PKEY_CTX; |
| |
| static int pkey_tls1_prf_init(EVP_PKEY_CTX *ctx) |
| { |
| TLS1_PRF_PKEY_CTX *kctx; |
| |
| if ((kctx = OPENSSL_zalloc(sizeof(*kctx))) == NULL) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_INIT, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| ctx->data = kctx; |
| |
| return 1; |
| } |
| |
| static void pkey_tls1_prf_cleanup(EVP_PKEY_CTX *ctx) |
| { |
| TLS1_PRF_PKEY_CTX *kctx = ctx->data; |
| OPENSSL_clear_free(kctx->sec, kctx->seclen); |
| OPENSSL_cleanse(kctx->seed, kctx->seedlen); |
| OPENSSL_free(kctx); |
| } |
| |
| static int pkey_tls1_prf_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) |
| { |
| TLS1_PRF_PKEY_CTX *kctx = ctx->data; |
| switch (type) { |
| case EVP_PKEY_CTRL_TLS_MD: |
| kctx->md = p2; |
| return 1; |
| |
| case EVP_PKEY_CTRL_TLS_SECRET: |
| if (p1 < 0) |
| return 0; |
| if (kctx->sec != NULL) |
| OPENSSL_clear_free(kctx->sec, kctx->seclen); |
| OPENSSL_cleanse(kctx->seed, kctx->seedlen); |
| kctx->seedlen = 0; |
| kctx->sec = OPENSSL_memdup(p2, p1); |
| if (kctx->sec == NULL) |
| return 0; |
| kctx->seclen = p1; |
| return 1; |
| |
| case EVP_PKEY_CTRL_TLS_SEED: |
| if (p1 == 0 || p2 == NULL) |
| return 1; |
| if (p1 < 0 || p1 > (int)(TLS1_PRF_MAXBUF - kctx->seedlen)) |
| return 0; |
| memcpy(kctx->seed + kctx->seedlen, p2, p1); |
| kctx->seedlen += p1; |
| return 1; |
| |
| default: |
| return -2; |
| |
| } |
| } |
| |
| static int pkey_tls1_prf_ctrl_str(EVP_PKEY_CTX *ctx, |
| const char *type, const char *value) |
| { |
| if (value == NULL) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_VALUE_MISSING); |
| return 0; |
| } |
| if (strcmp(type, "md") == 0) { |
| TLS1_PRF_PKEY_CTX *kctx = ctx->data; |
| |
| const EVP_MD *md = EVP_get_digestbyname(value); |
| if (md == NULL) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_INVALID_DIGEST); |
| return 0; |
| } |
| kctx->md = md; |
| return 1; |
| } |
| if (strcmp(type, "secret") == 0) |
| return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value); |
| if (strcmp(type, "hexsecret") == 0) |
| return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SECRET, value); |
| if (strcmp(type, "seed") == 0) |
| return EVP_PKEY_CTX_str2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value); |
| if (strcmp(type, "hexseed") == 0) |
| return EVP_PKEY_CTX_hex2ctrl(ctx, EVP_PKEY_CTRL_TLS_SEED, value); |
| |
| KDFerr(KDF_F_PKEY_TLS1_PRF_CTRL_STR, KDF_R_UNKNOWN_PARAMETER_TYPE); |
| return -2; |
| } |
| |
| static int pkey_tls1_prf_derive(EVP_PKEY_CTX *ctx, unsigned char *key, |
| size_t *keylen) |
| { |
| TLS1_PRF_PKEY_CTX *kctx = ctx->data; |
| if (kctx->md == NULL) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_DERIVE, KDF_R_MISSING_MESSAGE_DIGEST); |
| return 0; |
| } |
| if (kctx->sec == NULL) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_DERIVE, KDF_R_MISSING_SECRET); |
| return 0; |
| } |
| if (kctx->seedlen == 0) { |
| KDFerr(KDF_F_PKEY_TLS1_PRF_DERIVE, KDF_R_MISSING_SEED); |
| return 0; |
| } |
| return tls1_prf_alg(kctx->md, kctx->sec, kctx->seclen, |
| kctx->seed, kctx->seedlen, |
| key, *keylen); |
| } |
| |
| const EVP_PKEY_METHOD tls1_prf_pkey_meth = { |
| EVP_PKEY_TLS1_PRF, |
| 0, |
| pkey_tls1_prf_init, |
| 0, |
| pkey_tls1_prf_cleanup, |
| |
| 0, 0, |
| 0, 0, |
| |
| 0, |
| 0, |
| |
| 0, |
| 0, |
| |
| 0, 0, |
| |
| 0, 0, 0, 0, |
| |
| 0, 0, |
| |
| 0, 0, |
| |
| 0, |
| pkey_tls1_prf_derive, |
| pkey_tls1_prf_ctrl, |
| pkey_tls1_prf_ctrl_str |
| }; |
| |
| static int tls1_prf_P_hash(const EVP_MD *md, |
| const unsigned char *sec, size_t sec_len, |
| const unsigned char *seed, size_t seed_len, |
| unsigned char *out, size_t olen) |
| { |
| int chunk; |
| EVP_MD_CTX *ctx = NULL, *ctx_tmp = NULL, *ctx_init = NULL; |
| EVP_PKEY *mac_key = NULL; |
| unsigned char A1[EVP_MAX_MD_SIZE]; |
| size_t A1_len; |
| int ret = 0; |
| |
| chunk = EVP_MD_size(md); |
| if (!ossl_assert(chunk > 0)) |
| goto err; |
| |
| ctx = EVP_MD_CTX_new(); |
| ctx_tmp = EVP_MD_CTX_new(); |
| ctx_init = EVP_MD_CTX_new(); |
| if (ctx == NULL || ctx_tmp == NULL || ctx_init == NULL) |
| goto err; |
| EVP_MD_CTX_set_flags(ctx_init, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW); |
| mac_key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, sec, sec_len); |
| if (mac_key == NULL) |
| goto err; |
| if (!EVP_DigestSignInit(ctx_init, NULL, md, NULL, mac_key)) |
| goto err; |
| if (!EVP_MD_CTX_copy_ex(ctx, ctx_init)) |
| goto err; |
| if (seed != NULL && !EVP_DigestSignUpdate(ctx, seed, seed_len)) |
| goto err; |
| if (!EVP_DigestSignFinal(ctx, A1, &A1_len)) |
| goto err; |
| |
| for (;;) { |
| /* Reinit mac contexts */ |
| if (!EVP_MD_CTX_copy_ex(ctx, ctx_init)) |
| goto err; |
| if (!EVP_DigestSignUpdate(ctx, A1, A1_len)) |
| goto err; |
| if (olen > (size_t)chunk && !EVP_MD_CTX_copy_ex(ctx_tmp, ctx)) |
| goto err; |
| if (seed && !EVP_DigestSignUpdate(ctx, seed, seed_len)) |
| goto err; |
| |
| if (olen > (size_t)chunk) { |
| size_t mac_len; |
| if (!EVP_DigestSignFinal(ctx, out, &mac_len)) |
| goto err; |
| out += mac_len; |
| olen -= mac_len; |
| /* calc the next A1 value */ |
| if (!EVP_DigestSignFinal(ctx_tmp, A1, &A1_len)) |
| goto err; |
| } else { /* last one */ |
| |
| if (!EVP_DigestSignFinal(ctx, A1, &A1_len)) |
| goto err; |
| memcpy(out, A1, olen); |
| break; |
| } |
| } |
| ret = 1; |
| err: |
| EVP_PKEY_free(mac_key); |
| EVP_MD_CTX_free(ctx); |
| EVP_MD_CTX_free(ctx_tmp); |
| EVP_MD_CTX_free(ctx_init); |
| OPENSSL_cleanse(A1, sizeof(A1)); |
| return ret; |
| } |
| |
| static int tls1_prf_alg(const EVP_MD *md, |
| const unsigned char *sec, size_t slen, |
| const unsigned char *seed, size_t seed_len, |
| unsigned char *out, size_t olen) |
| { |
| |
| if (EVP_MD_type(md) == NID_md5_sha1) { |
| size_t i; |
| unsigned char *tmp; |
| if (!tls1_prf_P_hash(EVP_md5(), sec, slen/2 + (slen & 1), |
| seed, seed_len, out, olen)) |
| return 0; |
| |
| if ((tmp = OPENSSL_malloc(olen)) == NULL) { |
| KDFerr(KDF_F_TLS1_PRF_ALG, ERR_R_MALLOC_FAILURE); |
| return 0; |
| } |
| if (!tls1_prf_P_hash(EVP_sha1(), sec + slen/2, slen/2 + (slen & 1), |
| seed, seed_len, tmp, olen)) { |
| OPENSSL_clear_free(tmp, olen); |
| return 0; |
| } |
| for (i = 0; i < olen; i++) |
| out[i] ^= tmp[i]; |
| OPENSSL_clear_free(tmp, olen); |
| return 1; |
| } |
| if (!tls1_prf_P_hash(md, sec, slen, seed, seed_len, out, olen)) |
| return 0; |
| |
| return 1; |
| } |
