Backport of https://github.com/cisco/libsrtp/commit/5781341d99cd286a1f3d164e0576c2e837a444b7 --- a/crypto/hash/hmac_ossl.c 2017-08-01 11:57:38 UTC +++ b/crypto/hash/hmac_ossl.c @@ -46,11 +46,12 @@ #include #endif -#include "hmac.h" +#include "auth.h" #include "alloc.h" #include +#include -#define HMAC_KEYLEN_MAX 20 +#define SHA1_DIGEST_SIZE 20 /* the debug module for authentiation */ @@ -65,26 +66,18 @@ hmac_alloc (auth_t **a, int key_len, int out_len) { extern auth_type_t hmac; uint8_t *pointer; - hmac_ctx_t *new_hmac_ctx; + HMAC_CTX *new_hmac_ctx; debug_print(mod_hmac, "allocating auth func with key length %d", key_len); debug_print(mod_hmac, " tag length %d", out_len); - /* - * check key length - note that we don't support keys larger - * than 20 bytes yet - */ - if (key_len > HMAC_KEYLEN_MAX) { - return err_status_bad_param; - } - /* check output length - should be less than 20 bytes */ - if (out_len > HMAC_KEYLEN_MAX) { + if (out_len > SHA1_DIGEST_SIZE) { return err_status_bad_param; } - /* allocate memory for auth and hmac_ctx_t structures */ - pointer = (uint8_t*)crypto_alloc(sizeof(hmac_ctx_t) + sizeof(auth_t)); + /* allocate memory for auth and HMAC_CTX structures */ + pointer = (uint8_t*)crypto_alloc(sizeof(HMAC_CTX) + sizeof(auth_t)); if (pointer == NULL) { return err_status_alloc_fail; } @@ -96,8 +89,8 @@ hmac_alloc (auth_t **a, int key_len, int out_len) (*a)->out_len = out_len; (*a)->key_len = key_len; (*a)->prefix_len = 0; - new_hmac_ctx = (hmac_ctx_t*)((*a)->state); - memset(new_hmac_ctx, 0, sizeof(hmac_ctx_t)); + new_hmac_ctx = (HMAC_CTX*)((*a)->state); + HMAC_CTX_init(new_hmac_ctx); /* increment global count of all hmac uses */ hmac.ref_count++; @@ -109,19 +102,15 @@ err_status_t hmac_dealloc (auth_t *a) { extern auth_type_t hmac; - hmac_ctx_t *hmac_ctx; + HMAC_CTX *hmac_ctx; - hmac_ctx = (hmac_ctx_t*)a->state; - if (hmac_ctx->ctx_initialized) { - EVP_MD_CTX_cleanup(&hmac_ctx->ctx); - } - if (hmac_ctx->init_ctx_initialized) { - EVP_MD_CTX_cleanup(&hmac_ctx->init_ctx); - } + hmac_ctx = (HMAC_CTX*)a->state; + HMAC_CTX_cleanup(hmac_ctx); + /* zeroize entire state*/ octet_string_set_to_zero((uint8_t*)a, - sizeof(hmac_ctx_t) + sizeof(auth_t)); + sizeof(HMAC_CTX) + sizeof(auth_t)); /* free memory */ crypto_free(a); @@ -133,113 +122,65 @@ hmac_dealloc (auth_t *a) } err_status_t -hmac_init (hmac_ctx_t *state, const uint8_t *key, int key_len) +hmac_init (HMAC_CTX *state, const uint8_t *key, int key_len) { - int i; - uint8_t ipad[64]; + if (HMAC_Init_ex(state, key, key_len, EVP_sha1(), NULL) == 0) + return err_status_auth_fail; - /* - * check key length - note that we don't support keys larger - * than 20 bytes yet - */ - if (key_len > HMAC_KEYLEN_MAX) { - return err_status_bad_param; - } - - /* - * set values of ipad and opad by exoring the key into the - * appropriate constant values - */ - for (i = 0; i < key_len; i++) { - ipad[i] = key[i] ^ 0x36; - state->opad[i] = key[i] ^ 0x5c; - } - /* set the rest of ipad, opad to constant values */ - for (; i < sizeof(ipad); i++) { - ipad[i] = 0x36; - ((uint8_t*)state->opad)[i] = 0x5c; - } - - debug_print(mod_hmac, "ipad: %s", octet_string_hex_string(ipad, sizeof(ipad))); - - /* initialize sha1 context */ - sha1_init(&state->init_ctx); - state->init_ctx_initialized = 1; - - /* hash ipad ^ key */ - sha1_update(&state->init_ctx, ipad, sizeof(ipad)); - return (hmac_start(state)); + return err_status_ok; } err_status_t -hmac_start (hmac_ctx_t *state) +hmac_start (HMAC_CTX *state) { - if (state->ctx_initialized) { - EVP_MD_CTX_cleanup(&state->ctx); - } - if (!EVP_MD_CTX_copy(&state->ctx, &state->init_ctx)) { + if (HMAC_Init_ex(state, NULL, 0, NULL, NULL) == 0) return err_status_auth_fail; - } else { - state->ctx_initialized = 1; - return err_status_ok; - } + + return err_status_ok; } err_status_t -hmac_update (hmac_ctx_t *state, const uint8_t *message, int msg_octets) +hmac_update (HMAC_CTX *state, const uint8_t *message, int msg_octets) { debug_print(mod_hmac, "input: %s", octet_string_hex_string(message, msg_octets)); - /* hash message into sha1 context */ - sha1_update(&state->ctx, message, msg_octets); + if (HMAC_Update(state, message, msg_octets) == 0) + return err_status_auth_fail; return err_status_ok; } err_status_t -hmac_compute (hmac_ctx_t *state, const void *message, +hmac_compute (HMAC_CTX *state, const void *message, int msg_octets, int tag_len, uint8_t *result) { - uint32_t hash_value[5]; - uint32_t H[5]; + uint8_t hash_value[SHA1_DIGEST_SIZE]; int i; + unsigned int len; /* check tag length, return error if we can't provide the value expected */ - if (tag_len > HMAC_KEYLEN_MAX) { + if (tag_len > SHA1_DIGEST_SIZE) { return err_status_bad_param; } /* hash message, copy output into H */ - sha1_update(&state->ctx, message, msg_octets); - sha1_final(&state->ctx, H); + if (HMAC_Update(state, message, msg_octets) == 0) + return err_status_auth_fail; - /* - * note that we don't need to debug_print() the input, since the - * function hmac_update() already did that for us - */ - debug_print(mod_hmac, "intermediate state: %s", - octet_string_hex_string((uint8_t*)H, sizeof(H))); + if (HMAC_Final(state, hash_value, &len) == 0) + return err_status_auth_fail; - /* re-initialize hash context */ - sha1_init(&state->ctx); + if (len < tag_len) + return err_status_auth_fail; - /* hash opad ^ key */ - sha1_update(&state->ctx, (uint8_t*)state->opad, sizeof(state->opad)); - - /* hash the result of the inner hash */ - sha1_update(&state->ctx, (uint8_t*)H, sizeof(H)); - - /* the result is returned in the array hash_value[] */ - sha1_final(&state->ctx, hash_value); - /* copy hash_value to *result */ for (i = 0; i < tag_len; i++) { - result[i] = ((uint8_t*)hash_value)[i]; + result[i] = hash_value[i]; } debug_print(mod_hmac, "output: %s", - octet_string_hex_string((uint8_t*)hash_value, tag_len)); + octet_string_hex_string(hash_value, tag_len)); return err_status_ok; } @@ -248,7 +189,7 @@ hmac_compute (hmac_ctx_t *state, const void *message, /* begin test case 0 */ uint8_t - hmac_test_case_0_key[HMAC_KEYLEN_MAX] = { + hmac_test_case_0_key[SHA1_DIGEST_SIZE] = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b @@ -260,7 +201,7 @@ uint8_t }; uint8_t - hmac_test_case_0_tag[HMAC_KEYLEN_MAX] = { + hmac_test_case_0_tag[SHA1_DIGEST_SIZE] = { 0xb6, 0x17, 0x31, 0x86, 0x55, 0x05, 0x72, 0x64, 0xe2, 0x8b, 0xc0, 0xb6, 0xfb, 0x37, 0x8c, 0x8e, 0xf1, 0x46, 0xbe, 0x00 --- a/crypto/include/hmac.h 2017-08-01 11:57:38 UTC +++ b/crypto/include/hmac.h @@ -53,10 +53,6 @@ typedef struct { uint8_t opad[64]; sha1_ctx_t ctx; sha1_ctx_t init_ctx; -#ifdef OPENSSL - int ctx_initialized; - int init_ctx_initialized; -#endif } hmac_ctx_t; err_status_t