Update HMAC to support key == NULL or keylen == 0

This commit is contained in:
Zhi Guan
2026-06-09 15:14:37 +08:00
parent 849491cb33
commit d1d75a3109
2 changed files with 52 additions and 50 deletions

View File

@@ -30,8 +30,6 @@ typedef struct hmac_ctx_st {
} HMAC_CTX; } HMAC_CTX;
size_t hmac_size(const HMAC_CTX *ctx);
int hmac_init(HMAC_CTX *ctx, const DIGEST *digest, const uint8_t *key, size_t keylen); int hmac_init(HMAC_CTX *ctx, const DIGEST *digest, const uint8_t *key, size_t keylen);
int hmac_update(HMAC_CTX *ctx, const uint8_t *data, size_t datalen); int hmac_update(HMAC_CTX *ctx, const uint8_t *data, size_t datalen);
int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen); int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen);

View File

@@ -1,5 +1,5 @@
/* /*
* Copyright 2014-2022 The GmSSL Project. All Rights Reserved. * Copyright 2014-2026 The GmSSL Project. All Rights Reserved.
* *
* Licensed under the Apache License, Version 2.0 (the License); you may * Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License. * not use this file except in compliance with the License.
@@ -9,6 +9,7 @@
#include <string.h> #include <string.h>
#include <gmssl/mem.h>
#include <gmssl/hmac.h> #include <gmssl/hmac.h>
#include <gmssl/error.h> #include <gmssl/error.h>
@@ -20,51 +21,75 @@
int hmac_init(HMAC_CTX *ctx, const DIGEST *digest, const uint8_t *key, size_t keylen) int hmac_init(HMAC_CTX *ctx, const DIGEST *digest, const uint8_t *key, size_t keylen)
{ {
uint8_t i_key[DIGEST_MAX_BLOCK_SIZE] = {0}; uint8_t i_key[DIGEST_MAX_BLOCK_SIZE] = {0};
uint8_t o_key[DIGEST_MAX_BLOCK_SIZE] = {0}; uint8_t o_key[sizeof(i_key)] = {0};
size_t blocksize; size_t blocksize;
size_t i; size_t i;
if (!ctx || !digest || !key || !keylen) { if (!ctx || !digest) {
error_print();
return -1;
}
if (digest->block_size > sizeof(i_key)
|| digest->digest_size > HMAC_MAX_SIZE
|| !digest->digest_size
|| !digest->block_size) {
error_print();
return -1;
}
if (!key && keylen) {
error_print(); error_print();
return -1; return -1;
} }
ctx->digest = digest; ctx->digest = digest;
blocksize = digest->block_size; blocksize = digest->block_size;
if (keylen <= blocksize) {
if (key) {
if (keylen > blocksize) {
if (digest_init(&ctx->digest_ctx, digest) != 1
|| digest_update(&ctx->digest_ctx, key, keylen) != 1
|| digest_finish(&ctx->digest_ctx, i_key, &keylen) != 1) {
error_print();
return -1;
}
memcpy(o_key, i_key, keylen);
} else if (keylen) {
memcpy(i_key, key, keylen); memcpy(i_key, key, keylen);
memcpy(o_key, key, keylen); memcpy(o_key, key, keylen);
} else {
digest_init(&ctx->digest_ctx, digest);
digest_update(&ctx->digest_ctx, key, keylen);
digest_finish(&ctx->digest_ctx, i_key, &keylen);
memcpy(o_key, i_key, keylen);
} }
}
for (i = 0; i < blocksize; i++) { for (i = 0; i < blocksize; i++) {
i_key[i] ^= IPAD; i_key[i] ^= IPAD;
o_key[i] ^= OPAD; o_key[i] ^= OPAD;
} }
digest_init(&ctx->i_ctx, digest); if (digest_init(&ctx->i_ctx, digest) != 1
digest_update(&ctx->i_ctx, i_key, blocksize); || digest_update(&ctx->i_ctx, i_key, blocksize) != 1
digest_init(&ctx->o_ctx, digest); || digest_init(&ctx->o_ctx, digest) != 1
digest_update(&ctx->o_ctx, o_key, blocksize); || digest_update(&ctx->o_ctx, o_key, blocksize) != 1) {
error_print();
return -1;
}
memcpy(&ctx->digest_ctx, &ctx->i_ctx, sizeof(DIGEST_CTX)); memcpy(&ctx->digest_ctx, &ctx->i_ctx, sizeof(DIGEST_CTX));
memset(i_key, 0, sizeof(i_key)); gmssl_secure_clear(i_key, sizeof(i_key));
memset(o_key, 0, sizeof(o_key)); gmssl_secure_clear(o_key, sizeof(o_key));
return 1; return 1;
} }
int hmac_update(HMAC_CTX *ctx, const uint8_t *data, size_t datalen) int hmac_update(HMAC_CTX *ctx, const uint8_t *data, size_t datalen)
{ {
if (ctx == NULL) { if (!ctx) {
error_print(); error_print();
return -1; return -1;
} }
if (data == NULL || datalen == 0) { if (!data && datalen) {
return 0; error_print();
return -1;
}
if (!data || datalen == 0) {
return 1;
} }
if (digest_update(&ctx->digest_ctx, data, datalen) != 1) { if (digest_update(&ctx->digest_ctx, data, datalen) != 1) {
error_print(); error_print();
@@ -75,7 +100,7 @@ int hmac_update(HMAC_CTX *ctx, const uint8_t *data, size_t datalen)
int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen) int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen)
{ {
if (ctx == NULL || maclen == NULL) { if (!ctx || !mac || !maclen) {
error_print(); error_print();
return -1; return -1;
} }
@@ -84,7 +109,7 @@ int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen)
return -1; return -1;
} }
memcpy(&ctx->digest_ctx, &ctx->o_ctx, sizeof(DIGEST_CTX)); memcpy(&ctx->digest_ctx, &ctx->o_ctx, sizeof(DIGEST_CTX));
if (digest_update(&ctx->digest_ctx, mac, *maclen) != 1 if (digest_update(&ctx->digest_ctx, mac, ctx->digest->digest_size) != 1
|| digest_finish(&ctx->digest_ctx, mac, maclen) != 1) { || digest_finish(&ctx->digest_ctx, mac, maclen) != 1) {
error_print(); error_print();
return -1; return -1;
@@ -92,38 +117,17 @@ int hmac_finish(HMAC_CTX *ctx, uint8_t *mac, size_t *maclen)
return 1; return 1;
} }
int hmac_finish_and_verify(HMAC_CTX *ctx, const uint8_t *mac, size_t maclen)
{
uint8_t hmac[64];
size_t hmaclen;
if (hmac_finish(ctx, hmac, &hmaclen) != 1) {
error_print();
return -1;
}
if (maclen != hmaclen
|| memcmp(hmac, mac, maclen) != 0) {
error_print();
return -1;
}
return 1;
}
int hmac(const DIGEST *digest, const uint8_t *key, size_t keylen, int hmac(const DIGEST *digest, const uint8_t *key, size_t keylen,
const uint8_t *data, size_t datalen, const uint8_t *data, size_t datalen,
uint8_t *mac, size_t *maclen) uint8_t *mac, size_t *maclen)
{ {
int ret = 0;
HMAC_CTX ctx; HMAC_CTX ctx;
if (hmac_init(&ctx, digest, key, keylen) != 1 if (hmac_init(&ctx, digest, key, keylen) != 1
|| hmac_update(&ctx, data, datalen) != 1 || hmac_update(&ctx, data, datalen) != 1
|| hmac_finish(&ctx, mac, maclen) != 1) { || hmac_finish(&ctx, mac, maclen) != 1) {
goto end; gmssl_secure_clear(&ctx, sizeof(ctx));
return -1;
} }
ret = 1; gmssl_secure_clear(&ctx, sizeof(ctx));
return 1;
end:
memset(&ctx, 0, sizeof(ctx));
return ret;
} }