diff options
Diffstat (limited to 'security/nss/lib/freebl/alghmac.c')
| -rw-r--r-- | security/nss/lib/freebl/alghmac.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/alghmac.c b/security/nss/lib/freebl/alghmac.c new file mode 100644 index 0000000000..58bbaa9ec8 --- /dev/null +++ b/security/nss/lib/freebl/alghmac.c @@ -0,0 +1,209 @@ +/* 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/. */ + +#ifdef FREEBL_NO_DEPEND +#include "stubs.h" +#endif + +#include "secport.h" +#include "hasht.h" +#include "blapit.h" +#include "alghmac.h" +#include "secerr.h" + +#define HMAC_PAD_SIZE HASH_BLOCK_LENGTH_MAX + +struct HMACContextStr { + void *hash; + const SECHashObject *hashobj; + PRBool wasAllocated; + unsigned char ipad[HMAC_PAD_SIZE]; + unsigned char opad[HMAC_PAD_SIZE]; +}; + +void +HMAC_Destroy(HMACContext *cx, PRBool freeit) +{ + if (cx == NULL) + return; + + PORT_Assert(!freeit == !cx->wasAllocated); + if (cx->hash != NULL) { + cx->hashobj->destroy(cx->hash, PR_TRUE); + PORT_Memset(cx, 0, sizeof *cx); + } + if (freeit) + PORT_Free(cx); +} + +static SECStatus +hmac_initKey(HMACContext *cx, const unsigned char *secret, + unsigned int secret_len, PRBool isFIPS) +{ + unsigned int i; + unsigned char hashed_secret[HASH_LENGTH_MAX]; + + /* required by FIPS 198 Section 3 */ + if (isFIPS && secret_len < cx->hashobj->length / 2) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + + if (secret_len > cx->hashobj->blocklength) { + cx->hashobj->begin(cx->hash); + cx->hashobj->update(cx->hash, secret, secret_len); + PORT_Assert(cx->hashobj->length <= sizeof hashed_secret); + cx->hashobj->end(cx->hash, hashed_secret, &secret_len, + sizeof hashed_secret); + if (secret_len != cx->hashobj->length) { + PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); + goto loser; + } + secret = (const unsigned char *)&hashed_secret[0]; + } + + PORT_Memset(cx->ipad, 0x36, cx->hashobj->blocklength); + PORT_Memset(cx->opad, 0x5c, cx->hashobj->blocklength); + + /* fold secret into padding */ + for (i = 0; i < secret_len; i++) { + cx->ipad[i] ^= secret[i]; + cx->opad[i] ^= secret[i]; + } + PORT_Memset(hashed_secret, 0, sizeof hashed_secret); + return SECSuccess; + +loser: + PORT_Memset(hashed_secret, 0, sizeof hashed_secret); + return SECFailure; +} + +SECStatus +HMAC_Init(HMACContext *cx, const SECHashObject *hash_obj, + const unsigned char *secret, unsigned int secret_len, PRBool isFIPS) +{ + SECStatus rv; + + if (cx == NULL) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + cx->wasAllocated = PR_FALSE; + cx->hashobj = hash_obj; + cx->hash = cx->hashobj->create(); + if (cx->hash == NULL) + goto loser; + + rv = hmac_initKey(cx, secret, secret_len, isFIPS); + if (rv != SECSuccess) + goto loser; + + return rv; +loser: + if (cx->hash != NULL) + cx->hashobj->destroy(cx->hash, PR_TRUE); + return SECFailure; +} + +HMACContext * +HMAC_Create(const SECHashObject *hash_obj, const unsigned char *secret, + unsigned int secret_len, PRBool isFIPS) +{ + SECStatus rv; + HMACContext *cx = PORT_ZNew(HMACContext); + if (cx == NULL) + return NULL; + rv = HMAC_Init(cx, hash_obj, secret, secret_len, isFIPS); + cx->wasAllocated = PR_TRUE; + if (rv != SECSuccess) { + PORT_Free(cx); /* contains no secret info */ + cx = NULL; + } + return cx; +} + +/* this allows us to reuse an existing HMACContext with a new key and + * Hash function */ +SECStatus +HMAC_ReInit(HMACContext *cx, const SECHashObject *hash_obj, + const unsigned char *secret, unsigned int secret_len, PRBool isFIPS) +{ + PRBool wasAllocated; + SECStatus rv; + + /* if we are using the same hash, keep the hash contexts and only + * init the key */ + if ((cx->hashobj == hash_obj) && (cx->hash != NULL)) { + return hmac_initKey(cx, secret, secret_len, isFIPS); + } + /* otherwise we destroy the contents of the context and + * initalize it from scratch. We need to preseve the current state + * of wasAllocated to the final destroy works correctly */ + wasAllocated = cx->wasAllocated; + cx->wasAllocated = PR_FALSE; + HMAC_Destroy(cx, PR_FALSE); + rv = HMAC_Init(cx, hash_obj, secret, secret_len, isFIPS); + if (rv != SECSuccess) { + return rv; + } + cx->wasAllocated = wasAllocated; + return SECSuccess; +} + +void +HMAC_Begin(HMACContext *cx) +{ + /* start inner hash */ + cx->hashobj->begin(cx->hash); + cx->hashobj->update(cx->hash, cx->ipad, cx->hashobj->blocklength); +} + +void +HMAC_Update(HMACContext *cx, const unsigned char *data, unsigned int data_len) +{ + cx->hashobj->update(cx->hash, data, data_len); +} + +SECStatus +HMAC_Finish(HMACContext *cx, unsigned char *result, unsigned int *result_len, + unsigned int max_result_len) +{ + if (max_result_len < cx->hashobj->length) { + PORT_SetError(SEC_ERROR_INVALID_ARGS); + return SECFailure; + } + + cx->hashobj->end(cx->hash, result, result_len, max_result_len); + if (*result_len != cx->hashobj->length) + return SECFailure; + + cx->hashobj->begin(cx->hash); + cx->hashobj->update(cx->hash, cx->opad, cx->hashobj->blocklength); + cx->hashobj->update(cx->hash, result, *result_len); + cx->hashobj->end(cx->hash, result, result_len, max_result_len); + return SECSuccess; +} + +HMACContext * +HMAC_Clone(HMACContext *cx) +{ + HMACContext *newcx; + + newcx = (HMACContext *)PORT_ZAlloc(sizeof(HMACContext)); + if (newcx == NULL) + goto loser; + + newcx->wasAllocated = PR_TRUE; + newcx->hashobj = cx->hashobj; + newcx->hash = cx->hashobj->clone(cx->hash); + if (newcx->hash == NULL) + goto loser; + PORT_Memcpy(newcx->ipad, cx->ipad, cx->hashobj->blocklength); + PORT_Memcpy(newcx->opad, cx->opad, cx->hashobj->blocklength); + return newcx; + +loser: + HMAC_Destroy(newcx, PR_TRUE); + return NULL; +} |