diff options
Diffstat (limited to 'security/nss/lib/softoken/sftkhmac.c')
| -rw-r--r-- | security/nss/lib/softoken/sftkhmac.c | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/security/nss/lib/softoken/sftkhmac.c b/security/nss/lib/softoken/sftkhmac.c new file mode 100644 index 0000000000..bec2df79f1 --- /dev/null +++ b/security/nss/lib/softoken/sftkhmac.c @@ -0,0 +1,477 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "seccomon.h" +#include "secerr.h" +#include "blapi.h" +#include "pkcs11i.h" +#include "softoken.h" +#include "hmacct.h" + +/* sftk_HMACMechanismToHash converts a PKCS#11 MAC mechanism into a freebl hash + * type. */ +HASH_HashType +sftk_HMACMechanismToHash(CK_MECHANISM_TYPE mech) +{ + switch (mech) { + case CKM_MD2_HMAC: + return HASH_AlgMD2; + case CKM_MD5_HMAC: + case CKM_SSL3_MD5_MAC: + return HASH_AlgMD5; + case CKM_SHA_1_HMAC: + case CKM_SSL3_SHA1_MAC: + return HASH_AlgSHA1; + case CKM_SHA224_HMAC: + return HASH_AlgSHA224; + case CKM_SHA256_HMAC: + return HASH_AlgSHA256; + case CKM_SHA384_HMAC: + return HASH_AlgSHA384; + case CKM_SHA512_HMAC: + return HASH_AlgSHA512; + } + return HASH_AlgNULL; +} + +static sftk_MACConstantTimeCtx * +SetupMAC(CK_MECHANISM_PTR mech, SFTKObject *key) +{ + CK_NSS_MAC_CONSTANT_TIME_PARAMS *params = + (CK_NSS_MAC_CONSTANT_TIME_PARAMS *)mech->pParameter; + sftk_MACConstantTimeCtx *ctx; + HASH_HashType alg; + SFTKAttribute *keyval; + unsigned char secret[sizeof(ctx->secret)]; + unsigned int secretLength; + + if (mech->ulParameterLen != sizeof(CK_NSS_MAC_CONSTANT_TIME_PARAMS)) { + return NULL; + } + + alg = sftk_HMACMechanismToHash(params->macAlg); + if (alg == HASH_AlgNULL) { + return NULL; + } + + keyval = sftk_FindAttribute(key, CKA_VALUE); + if (keyval == NULL) { + return NULL; + } + secretLength = keyval->attrib.ulValueLen; + if (secretLength > sizeof(secret)) { + sftk_FreeAttribute(keyval); + return NULL; + } + memcpy(secret, keyval->attrib.pValue, secretLength); + sftk_FreeAttribute(keyval); + + ctx = PORT_Alloc(sizeof(sftk_MACConstantTimeCtx)); + if (!ctx) { + PORT_Memset(secret, 0, secretLength); + return NULL; + } + + memcpy(ctx->secret, secret, secretLength); + ctx->secretLength = secretLength; + ctx->hash = HASH_GetRawHashObject(alg); + ctx->totalLength = params->ulBodyTotalLen; + PORT_Memset(secret, 0, secretLength); + + return ctx; +} + +sftk_MACConstantTimeCtx * +sftk_HMACConstantTime_New(CK_MECHANISM_PTR mech, SFTKObject *key) +{ + CK_NSS_MAC_CONSTANT_TIME_PARAMS *params = + (CK_NSS_MAC_CONSTANT_TIME_PARAMS *)mech->pParameter; + sftk_MACConstantTimeCtx *ctx; + + if (params->ulHeaderLen > sizeof(ctx->header)) { + return NULL; + } + ctx = SetupMAC(mech, key); + if (!ctx) { + return NULL; + } + + ctx->headerLength = params->ulHeaderLen; + memcpy(ctx->header, params->pHeader, params->ulHeaderLen); + return ctx; +} + +sftk_MACConstantTimeCtx * +sftk_SSLv3MACConstantTime_New(CK_MECHANISM_PTR mech, SFTKObject *key) +{ + CK_NSS_MAC_CONSTANT_TIME_PARAMS *params = + (CK_NSS_MAC_CONSTANT_TIME_PARAMS *)mech->pParameter; + unsigned int padLength = 40, j; + sftk_MACConstantTimeCtx *ctx; + + if (params->macAlg != CKM_SSL3_MD5_MAC && + params->macAlg != CKM_SSL3_SHA1_MAC) { + return NULL; + } + ctx = SetupMAC(mech, key); + if (!ctx) { + return NULL; + } + + if (params->macAlg == CKM_SSL3_MD5_MAC) { + padLength = 48; + } + + ctx->headerLength = + ctx->secretLength + + padLength + + params->ulHeaderLen; + + if (ctx->headerLength > sizeof(ctx->header)) { + goto loser; + } + + j = 0; + memcpy(&ctx->header[j], ctx->secret, ctx->secretLength); + j += ctx->secretLength; + memset(&ctx->header[j], 0x36, padLength); + j += padLength; + memcpy(&ctx->header[j], params->pHeader, params->ulHeaderLen); + + return ctx; + +loser: + PORT_Free(ctx); + return NULL; +} + +void +sftk_HMACConstantTime_Update(void *pctx, const void *data, unsigned int len) +{ + sftk_MACConstantTimeCtx *ctx = (sftk_MACConstantTimeCtx *)pctx; + PORT_CheckSuccess(HMAC_ConstantTime( + ctx->mac, NULL, sizeof(ctx->mac), + ctx->hash, + ctx->secret, ctx->secretLength, + ctx->header, ctx->headerLength, + data, len, + ctx->totalLength)); +} + +void +sftk_SSLv3MACConstantTime_Update(void *pctx, const void *data, unsigned int len) +{ + sftk_MACConstantTimeCtx *ctx = (sftk_MACConstantTimeCtx *)pctx; + PORT_CheckSuccess(SSLv3_MAC_ConstantTime( + ctx->mac, NULL, sizeof(ctx->mac), + ctx->hash, + ctx->secret, ctx->secretLength, + ctx->header, ctx->headerLength, + data, len, + ctx->totalLength)); +} + +void +sftk_MACConstantTime_EndHash(void *pctx, void *out, unsigned int *outLength, + unsigned int maxLength) +{ + const sftk_MACConstantTimeCtx *ctx = (sftk_MACConstantTimeCtx *)pctx; + unsigned int toCopy = ctx->hash->length; + if (toCopy > maxLength) { + toCopy = maxLength; + } + memcpy(out, ctx->mac, toCopy); + if (outLength) { + *outLength = toCopy; + } +} + +void +sftk_MACConstantTime_DestroyContext(void *pctx, PRBool free) +{ + PORT_ZFree(pctx, sizeof(sftk_MACConstantTimeCtx)); +} + +CK_RV +sftk_MAC_Create(CK_MECHANISM_TYPE mech, SFTKObject *key, sftk_MACCtx **ret_ctx) +{ + CK_RV ret; + + if (ret_ctx == NULL || key == NULL) { + return CKR_HOST_MEMORY; + } + + *ret_ctx = PORT_New(sftk_MACCtx); + if (*ret_ctx == NULL) { + return CKR_HOST_MEMORY; + } + + ret = sftk_MAC_Init(*ret_ctx, mech, key); + if (ret != CKR_OK) { + sftk_MAC_Destroy(*ret_ctx, PR_TRUE); + } + + return ret; +} + +CK_RV +sftk_MAC_Init(sftk_MACCtx *ctx, CK_MECHANISM_TYPE mech, SFTKObject *key) +{ + SFTKAttribute *keyval = NULL; + PRBool isFIPS = sftk_isFIPS(key->slot->slotID); + CK_RV ret = CKR_OK; + + /* Find the actual value of the key. */ + keyval = sftk_FindAttribute(key, CKA_VALUE); + if (keyval == NULL) { + ret = CKR_KEY_SIZE_RANGE; + goto done; + } + + ret = sftk_MAC_InitRaw(ctx, mech, + (const unsigned char *)keyval->attrib.pValue, + keyval->attrib.ulValueLen, isFIPS); + +done: + if (keyval) { + sftk_FreeAttribute(keyval); + } + return ret; +} + +CK_RV +sftk_MAC_InitRaw(sftk_MACCtx *ctx, CK_MECHANISM_TYPE mech, const unsigned char *key, unsigned int key_len, PRBool isFIPS) +{ + const SECHashObject *hashObj = NULL; + CK_RV ret = CKR_OK; + + if (ctx == NULL) { + return CKR_HOST_MEMORY; + } + + /* Clear the context before use. */ + PORT_Memset(ctx, 0, sizeof(*ctx)); + + /* Save the mech. */ + ctx->mech = mech; + + /* Initialize the correct MAC context. */ + switch (mech) { + case CKM_MD2_HMAC: + case CKM_MD5_HMAC: + case CKM_SHA_1_HMAC: + case CKM_SHA224_HMAC: + case CKM_SHA256_HMAC: + case CKM_SHA384_HMAC: + case CKM_SHA512_HMAC: + hashObj = HASH_GetRawHashObject(sftk_HMACMechanismToHash(mech)); + + /* Because we condition above only on hashes we know to be valid, + * hashObj should never be NULL. This assert is only useful when + * adding a new hash function (for which only partial support has + * been added); thus there is no need to turn it into an if and + * avoid the NULL dereference on the following line. */ + PR_ASSERT(hashObj != NULL); + ctx->mac_size = hashObj->length; + + goto hmac; + case CKM_AES_CMAC: + ctx->mac.cmac = CMAC_Create(CMAC_AES, key, key_len); + ctx->destroy_func = (void (*)(void *, PRBool))(&CMAC_Destroy); + + /* Copy the behavior of sftk_doCMACInit here. */ + if (ctx->mac.cmac == NULL) { + if (PORT_GetError() == SEC_ERROR_INVALID_ARGS) { + ret = CKR_KEY_SIZE_RANGE; + goto done; + } + + ret = CKR_HOST_MEMORY; + goto done; + } + + ctx->mac_size = AES_BLOCK_SIZE; + + goto done; + default: + ret = CKR_MECHANISM_PARAM_INVALID; + goto done; + } + +hmac: + ctx->mac.hmac = HMAC_Create(hashObj, key, key_len, isFIPS); + ctx->destroy_func = (void (*)(void *, PRBool))(&HMAC_Destroy); + + /* Copy the behavior of sftk_doHMACInit here. */ + if (ctx->mac.hmac == NULL) { + if (PORT_GetError() == SEC_ERROR_INVALID_ARGS) { + ret = CKR_KEY_SIZE_RANGE; + goto done; + } + ret = CKR_HOST_MEMORY; + goto done; + } + + /* Semantics: HMAC and CMAC should behave the same. Begin HMAC now. */ + HMAC_Begin(ctx->mac.hmac); + +done: + /* Handle a failure: ctx->mac.raw should be NULL, but make sure + * destroy_func isn't set. */ + if (ret != CKR_OK) { + ctx->destroy_func = NULL; + } + + return ret; +} + +CK_RV +sftk_MAC_Reset(sftk_MACCtx *ctx) +{ + /* Useful for resetting the state of MAC prior to calling update again + * + * This lets the caller keep a single MAC instance and re-use it as long + * as the key stays the same. */ + switch (ctx->mech) { + case CKM_MD2_HMAC: + case CKM_MD5_HMAC: + case CKM_SHA_1_HMAC: + case CKM_SHA224_HMAC: + case CKM_SHA256_HMAC: + case CKM_SHA384_HMAC: + case CKM_SHA512_HMAC: + HMAC_Begin(ctx->mac.hmac); + break; + case CKM_AES_CMAC: + if (CMAC_Begin(ctx->mac.cmac) != SECSuccess) { + return CKR_FUNCTION_FAILED; + } + break; + default: + /* This shouldn't happen -- asserting indicates partial support + * for a new MAC type. */ + PR_ASSERT(PR_FALSE); + return CKR_FUNCTION_FAILED; + } + + return CKR_OK; +} + +CK_RV +sftk_MAC_Update(sftk_MACCtx *ctx, const CK_BYTE *data, unsigned int data_len) +{ + switch (ctx->mech) { + case CKM_MD2_HMAC: + case CKM_MD5_HMAC: + case CKM_SHA_1_HMAC: + case CKM_SHA224_HMAC: + case CKM_SHA256_HMAC: + case CKM_SHA384_HMAC: + case CKM_SHA512_HMAC: + /* HMAC doesn't indicate failure in the return code. */ + HMAC_Update(ctx->mac.hmac, data, data_len); + break; + case CKM_AES_CMAC: + /* CMAC indicates failure in the return code, however this is + * unlikely to occur. */ + if (CMAC_Update(ctx->mac.cmac, data, data_len) != SECSuccess) { + return CKR_FUNCTION_FAILED; + } + break; + default: + /* This shouldn't happen -- asserting indicates partial support + * for a new MAC type. */ + PR_ASSERT(PR_FALSE); + return CKR_FUNCTION_FAILED; + } + return CKR_OK; +} + +CK_RV +sftk_MAC_Finish(sftk_MACCtx *ctx, CK_BYTE_PTR result, unsigned int *result_len, unsigned int max_result_len) +{ + unsigned int actual_result_len; + + switch (ctx->mech) { + case CKM_MD2_HMAC: + case CKM_MD5_HMAC: + case CKM_SHA_1_HMAC: + case CKM_SHA224_HMAC: + case CKM_SHA256_HMAC: + case CKM_SHA384_HMAC: + case CKM_SHA512_HMAC: + /* HMAC doesn't indicate failure in the return code. Additionally, + * unlike CMAC, it doesn't support partial results. This means that we + * need to allocate a buffer if max_result_len < ctx->mac_size. */ + if (max_result_len >= ctx->mac_size) { + /* Split this into two calls to avoid an unnecessary stack + * allocation and memcpy when possible. */ + HMAC_Finish(ctx->mac.hmac, result, &actual_result_len, max_result_len); + } else { + uint8_t tmp_buffer[SFTK_MAX_MAC_LENGTH]; + + /* Assumption: buffer is large enough to hold this HMAC's + * output. */ + PR_ASSERT(SFTK_MAX_MAC_LENGTH >= ctx->mac_size); + + HMAC_Finish(ctx->mac.hmac, tmp_buffer, &actual_result_len, SFTK_MAX_MAC_LENGTH); + + if (actual_result_len > max_result_len) { + /* This should always be true since: + * + * (SFTK_MAX_MAC_LENGTH >= ctx->mac_size = + * actual_result_len) > max_result_len, + * + * but guard this truncation just in case. */ + actual_result_len = max_result_len; + } + + PORT_Memcpy(result, tmp_buffer, actual_result_len); + } + break; + case CKM_AES_CMAC: + /* CMAC indicates failure in the return code, however this is + * unlikely to occur. */ + if (CMAC_Finish(ctx->mac.cmac, result, &actual_result_len, max_result_len) != SECSuccess) { + return CKR_FUNCTION_FAILED; + } + break; + default: + /* This shouldn't happen -- asserting indicates partial support + * for a new MAC type. */ + PR_ASSERT(PR_FALSE); + return CKR_FUNCTION_FAILED; + } + + if (result_len) { + /* When result length is passed, inform the caller of its value. */ + *result_len = actual_result_len; + } else if (max_result_len == ctx->mac_size) { + /* Validate that the amount requested was what was actually given; the + * caller assumes that what they passed was the output size of the + * underlying MAC and that they got all the bytes the asked for. */ + PR_ASSERT(actual_result_len == max_result_len); + } + + return CKR_OK; +} + +void +sftk_MAC_Destroy(sftk_MACCtx *ctx, PRBool free_it) +{ + if (ctx == NULL) { + return; + } + + if (ctx->mac.raw != NULL && ctx->destroy_func != NULL) { + ctx->destroy_func(ctx->mac.raw, PR_TRUE); + } + + /* Clean up the struct so we don't double free accidentally. */ + PORT_Memset(ctx, 0, sizeof(sftk_MACCtx)); + + if (free_it == PR_TRUE) { + PORT_Free(ctx); + } +} |