wolf SSL
wolfSSL 3.11.1 for TLS1.3 beta
Diff: wolfcrypt/src/hmac.c
- Revision:
- 0:d92f9d21154c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/wolfcrypt/src/hmac.c Fri Jun 26 00:39:20 2015 +0000
@@ -0,0 +1,880 @@
+/* hmac.h
+ *
+ * Copyright (C) 2006-2015 wolfSSL Inc.
+ *
+ * This file is part of wolfSSL. (formerly known as CyaSSL)
+ *
+ * wolfSSL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#ifdef HAVE_CONFIG_H
+ #include <config.h>
+#endif
+
+#include <wolfssl/wolfcrypt/settings.h>
+
+#ifndef NO_HMAC
+
+#include <wolfssl/wolfcrypt/hmac.h>
+
+#ifdef HAVE_FIPS
+/* does init */
+int wc_HmacSetKey(Hmac* hmac, int type, const byte* key, word32 keySz)
+{
+ return HmacSetKey_fips(hmac, type, key, keySz);
+}
+
+
+int wc_HmacUpdate(Hmac* hmac, const byte* in, word32 sz)
+{
+ return HmacUpdate_fips(hmac, in, sz);
+}
+
+
+int wc_HmacFinal(Hmac* hmac, byte* out)
+{
+ return HmacFinal_fips(hmac, out);
+}
+
+
+#ifdef HAVE_CAVIUM
+ int wc_HmacInitCavium(Hmac* hmac, int i)
+ {
+ return HmacInitCavium(hmac, i);
+ }
+
+
+ void wc_HmacFreeCavium(Hmac* hmac)
+ {
+ HmacFreeCavium(hmac);
+ }
+#endif
+
+int wolfSSL_GetHmacMaxSize(void)
+{
+ return CyaSSL_GetHmacMaxSize();
+}
+
+#ifdef HAVE_HKDF
+
+int wc_HKDF(int type, const byte* inKey, word32 inKeySz,
+ const byte* salt, word32 saltSz,
+ const byte* info, word32 infoSz,
+ byte* out, word32 outSz)
+{
+ return HKDF(type, inKey, inKeySz, salt, saltSz, info, infoSz, out, outSz);
+}
+
+
+#endif /* HAVE_HKDF */
+#else /* else build without fips */
+#ifdef WOLFSSL_PIC32MZ_HASH
+
+#define wc_InitMd5 wc_InitMd5_sw
+#define wc_Md5Update wc_Md5Update_sw
+#define wc_Md5Final wc_Md5Final_sw
+
+#define wc_InitSha wc_InitSha_sw
+#define wc_ShaUpdate wc_ShaUpdate_sw
+#define wc_ShaFinal wc_ShaFinal_sw
+
+#define wc_InitSha256 wc_InitSha256_sw
+#define wc_Sha256Update wc_Sha256Update_sw
+#define wc_Sha256Final wc_Sha256Final_sw
+
+#endif
+
+#ifdef HAVE_FIPS
+ /* set NO_WRAPPERS before headers, use direct internal f()s not wrappers */
+ #define FIPS_NO_WRAPPERS
+#endif
+
+#include <wolfssl/wolfcrypt/error-crypt.h>
+
+
+#ifdef HAVE_CAVIUM
+ static void HmacCaviumFinal(Hmac* hmac, byte* hash);
+ static void HmacCaviumUpdate(Hmac* hmac, const byte* msg, word32 length);
+ static void HmacCaviumSetKey(Hmac* hmac, int type, const byte* key,
+ word32 length);
+#endif
+
+static int InitHmac(Hmac* hmac, int type)
+{
+ int ret = 0;
+
+ hmac->innerHashKeyed = 0;
+ hmac->macType = (byte)type;
+
+ if (!(type == MD5 || type == SHA || type == SHA256 || type == SHA384
+ || type == SHA512 || type == BLAKE2B_ID))
+ return BAD_FUNC_ARG;
+
+ switch (type) {
+ #ifndef NO_MD5
+ case MD5:
+ wc_InitMd5(&hmac->hash.md5);
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ ret = wc_InitSha(&hmac->hash.sha);
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ ret = wc_InitSha256(&hmac->hash.sha256);
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ ret = wc_InitSha384(&hmac->hash.sha384);
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ ret = wc_InitSha512(&hmac->hash.sha512);
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ ret = wc_InitBlake2b(&hmac->hash.blake2b, BLAKE2B_256);
+ break;
+ #endif
+
+ default:
+ return BAD_FUNC_ARG;
+ }
+
+ return ret;
+}
+
+
+int wc_HmacSetKey(Hmac* hmac, int type, const byte* key, word32 length)
+{
+ byte* ip = (byte*) hmac->ipad;
+ byte* op = (byte*) hmac->opad;
+ word32 i, hmac_block_size = 0;
+ int ret;
+
+#ifdef HAVE_CAVIUM
+ if (hmac->magic == WOLFSSL_HMAC_CAVIUM_MAGIC)
+ return HmacCaviumSetKey(hmac, type, key, length);
+#endif
+
+ ret = InitHmac(hmac, type);
+ if (ret != 0)
+ return ret;
+
+#ifdef HAVE_FIPS
+ if (length < HMAC_FIPS_MIN_KEY)
+ return HMAC_MIN_KEYLEN_E;
+#endif
+
+ switch (hmac->macType) {
+ #ifndef NO_MD5
+ case MD5:
+ {
+ hmac_block_size = MD5_BLOCK_SIZE;
+ if (length <= MD5_BLOCK_SIZE) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ wc_Md5Update(&hmac->hash.md5, key, length);
+ wc_Md5Final(&hmac->hash.md5, ip);
+ length = MD5_DIGEST_SIZE;
+ }
+ }
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ {
+ hmac_block_size = SHA_BLOCK_SIZE;
+ if (length <= SHA_BLOCK_SIZE) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ wc_ShaUpdate(&hmac->hash.sha, key, length);
+ wc_ShaFinal(&hmac->hash.sha, ip);
+ length = SHA_DIGEST_SIZE;
+ }
+ }
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ {
+ hmac_block_size = SHA256_BLOCK_SIZE;
+ if (length <= SHA256_BLOCK_SIZE) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ ret = wc_Sha256Update(&hmac->hash.sha256, key, length);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha256Final(&hmac->hash.sha256, ip);
+ if (ret != 0)
+ return ret;
+
+ length = SHA256_DIGEST_SIZE;
+ }
+ }
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ {
+ hmac_block_size = SHA384_BLOCK_SIZE;
+ if (length <= SHA384_BLOCK_SIZE) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ ret = wc_Sha384Update(&hmac->hash.sha384, key, length);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha384Final(&hmac->hash.sha384, ip);
+ if (ret != 0)
+ return ret;
+
+ length = SHA384_DIGEST_SIZE;
+ }
+ }
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ {
+ hmac_block_size = SHA512_BLOCK_SIZE;
+ if (length <= SHA512_BLOCK_SIZE) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ ret = wc_Sha512Update(&hmac->hash.sha512, key, length);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha512Final(&hmac->hash.sha512, ip);
+ if (ret != 0)
+ return ret;
+
+ length = SHA512_DIGEST_SIZE;
+ }
+ }
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ {
+ hmac_block_size = BLAKE2B_BLOCKBYTES;
+ if (length <= BLAKE2B_BLOCKBYTES) {
+ XMEMCPY(ip, key, length);
+ }
+ else {
+ ret = wc_Blake2bUpdate(&hmac->hash.blake2b, key, length);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Blake2bFinal(&hmac->hash.blake2b, ip, BLAKE2B_256);
+ if (ret != 0)
+ return ret;
+
+ length = BLAKE2B_256;
+ }
+ }
+ break;
+ #endif
+
+ default:
+ return BAD_FUNC_ARG;
+ }
+ if (length < hmac_block_size)
+ XMEMSET(ip + length, 0, hmac_block_size - length);
+
+ for(i = 0; i < hmac_block_size; i++) {
+ op[i] = ip[i] ^ OPAD;
+ ip[i] ^= IPAD;
+ }
+ return 0;
+}
+
+
+static int HmacKeyInnerHash(Hmac* hmac)
+{
+ int ret = 0;
+
+ switch (hmac->macType) {
+ #ifndef NO_MD5
+ case MD5:
+ wc_Md5Update(&hmac->hash.md5, (byte*) hmac->ipad, MD5_BLOCK_SIZE);
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ wc_ShaUpdate(&hmac->hash.sha, (byte*) hmac->ipad, SHA_BLOCK_SIZE);
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ ret = wc_Sha256Update(&hmac->hash.sha256,
+ (byte*) hmac->ipad, SHA256_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ ret = wc_Sha384Update(&hmac->hash.sha384,
+ (byte*) hmac->ipad, SHA384_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ ret = wc_Sha512Update(&hmac->hash.sha512,
+ (byte*) hmac->ipad, SHA512_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ ret = wc_Blake2bUpdate(&hmac->hash.blake2b,
+ (byte*) hmac->ipad,BLAKE2B_BLOCKBYTES);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ default:
+ break;
+ }
+
+ hmac->innerHashKeyed = 1;
+
+ return ret;
+}
+
+
+int wc_HmacUpdate(Hmac* hmac, const byte* msg, word32 length)
+{
+ int ret;
+
+#ifdef HAVE_CAVIUM
+ if (hmac->magic == WOLFSSL_HMAC_CAVIUM_MAGIC)
+ return HmacCaviumUpdate(hmac, msg, length);
+#endif
+
+ if (!hmac->innerHashKeyed) {
+ ret = HmacKeyInnerHash(hmac);
+ if (ret != 0)
+ return ret;
+ }
+
+ switch (hmac->macType) {
+ #ifndef NO_MD5
+ case MD5:
+ wc_Md5Update(&hmac->hash.md5, msg, length);
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ wc_ShaUpdate(&hmac->hash.sha, msg, length);
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ ret = wc_Sha256Update(&hmac->hash.sha256, msg, length);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ ret = wc_Sha384Update(&hmac->hash.sha384, msg, length);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ ret = wc_Sha512Update(&hmac->hash.sha512, msg, length);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ ret = wc_Blake2bUpdate(&hmac->hash.blake2b, msg, length);
+ if (ret != 0)
+ return ret;
+ break;
+ #endif
+
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+
+int wc_HmacFinal(Hmac* hmac, byte* hash)
+{
+ int ret;
+
+#ifdef HAVE_CAVIUM
+ if (hmac->magic == WOLFSSL_HMAC_CAVIUM_MAGIC)
+ return HmacCaviumFinal(hmac, hash);
+#endif
+
+ if (!hmac->innerHashKeyed) {
+ ret = HmacKeyInnerHash(hmac);
+ if (ret != 0)
+ return ret;
+ }
+
+ switch (hmac->macType) {
+ #ifndef NO_MD5
+ case MD5:
+ {
+ wc_Md5Final(&hmac->hash.md5, (byte*) hmac->innerHash);
+
+ wc_Md5Update(&hmac->hash.md5, (byte*) hmac->opad, MD5_BLOCK_SIZE);
+ wc_Md5Update(&hmac->hash.md5,
+ (byte*) hmac->innerHash, MD5_DIGEST_SIZE);
+
+ wc_Md5Final(&hmac->hash.md5, hash);
+ }
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ {
+ wc_ShaFinal(&hmac->hash.sha, (byte*) hmac->innerHash);
+
+ wc_ShaUpdate(&hmac->hash.sha, (byte*) hmac->opad, SHA_BLOCK_SIZE);
+ wc_ShaUpdate(&hmac->hash.sha,
+ (byte*) hmac->innerHash, SHA_DIGEST_SIZE);
+
+ wc_ShaFinal(&hmac->hash.sha, hash);
+ }
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ {
+ ret = wc_Sha256Final(&hmac->hash.sha256, (byte*) hmac->innerHash);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha256Update(&hmac->hash.sha256,
+ (byte*) hmac->opad, SHA256_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha256Update(&hmac->hash.sha256,
+ (byte*) hmac->innerHash, SHA256_DIGEST_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha256Final(&hmac->hash.sha256, hash);
+ if (ret != 0)
+ return ret;
+ }
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ {
+ ret = wc_Sha384Final(&hmac->hash.sha384, (byte*) hmac->innerHash);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha384Update(&hmac->hash.sha384,
+ (byte*) hmac->opad, SHA384_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha384Update(&hmac->hash.sha384,
+ (byte*) hmac->innerHash, SHA384_DIGEST_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha384Final(&hmac->hash.sha384, hash);
+ if (ret != 0)
+ return ret;
+ }
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ {
+ ret = wc_Sha512Final(&hmac->hash.sha512, (byte*) hmac->innerHash);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha512Update(&hmac->hash.sha512,
+ (byte*) hmac->opad, SHA512_BLOCK_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha512Update(&hmac->hash.sha512,
+ (byte*) hmac->innerHash, SHA512_DIGEST_SIZE);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Sha512Final(&hmac->hash.sha512, hash);
+ if (ret != 0)
+ return ret;
+ }
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ {
+ ret = wc_Blake2bFinal(&hmac->hash.blake2b, (byte*) hmac->innerHash,
+ BLAKE2B_256);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Blake2bUpdate(&hmac->hash.blake2b,
+ (byte*) hmac->opad, BLAKE2B_BLOCKBYTES);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Blake2bUpdate(&hmac->hash.blake2b,
+ (byte*) hmac->innerHash, BLAKE2B_256);
+ if (ret != 0)
+ return ret;
+
+ ret = wc_Blake2bFinal(&hmac->hash.blake2b, hash, BLAKE2B_256);
+ if (ret != 0)
+ return ret;
+ }
+ break;
+ #endif
+
+ default:
+ break;
+ }
+
+ hmac->innerHashKeyed = 0;
+
+ return 0;
+}
+
+
+#ifdef HAVE_CAVIUM
+
+/* Initiliaze Hmac for use with Nitrox device */
+int wc_HmacInitCavium(Hmac* hmac, int devId)
+{
+ if (hmac == NULL)
+ return -1;
+
+ if (CspAllocContext(CONTEXT_SSL, &hmac->contextHandle, devId) != 0)
+ return -1;
+
+ hmac->keyLen = 0;
+ hmac->dataLen = 0;
+ hmac->type = 0;
+ hmac->devId = devId;
+ hmac->magic = WOLFSSL_HMAC_CAVIUM_MAGIC;
+ hmac->data = NULL; /* buffered input data */
+
+ hmac->innerHashKeyed = 0;
+
+ return 0;
+}
+
+
+/* Free Hmac from use with Nitrox device */
+void wc_HmacFreeCavium(Hmac* hmac)
+{
+ if (hmac == NULL)
+ return;
+
+ CspFreeContext(CONTEXT_SSL, hmac->contextHandle, hmac->devId);
+ hmac->magic = 0;
+ XFREE(hmac->data, NULL, DYNAMIC_TYPE_CAVIUM_TMP);
+ hmac->data = NULL;
+}
+
+
+static void HmacCaviumFinal(Hmac* hmac, byte* hash)
+{
+ word32 requestId;
+
+ if (CspHmac(CAVIUM_BLOCKING, hmac->type, NULL, hmac->keyLen,
+ (byte*)hmac->ipad, hmac->dataLen, hmac->data, hash, &requestId,
+ hmac->devId) != 0) {
+ WOLFSSL_MSG("Cavium Hmac failed");
+ }
+ hmac->innerHashKeyed = 0; /* tell update to start over if used again */
+}
+
+
+static void HmacCaviumUpdate(Hmac* hmac, const byte* msg, word32 length)
+{
+ word16 add = (word16)length;
+ word32 total;
+ byte* tmp;
+
+ if (length > WOLFSSL_MAX_16BIT) {
+ WOLFSSL_MSG("Too big msg for cavium hmac");
+ return;
+ }
+
+ if (hmac->innerHashKeyed == 0) { /* starting new */
+ hmac->dataLen = 0;
+ hmac->innerHashKeyed = 1;
+ }
+
+ total = add + hmac->dataLen;
+ if (total > WOLFSSL_MAX_16BIT) {
+ WOLFSSL_MSG("Too big msg for cavium hmac");
+ return;
+ }
+
+ tmp = XMALLOC(hmac->dataLen + add, NULL,DYNAMIC_TYPE_CAVIUM_TMP);
+ if (tmp == NULL) {
+ WOLFSSL_MSG("Out of memory for cavium update");
+ return;
+ }
+ if (hmac->dataLen)
+ XMEMCPY(tmp, hmac->data, hmac->dataLen);
+ XMEMCPY(tmp + hmac->dataLen, msg, add);
+
+ hmac->dataLen += add;
+ XFREE(hmac->data, NULL, DYNAMIC_TYPE_CAVIUM_TMP);
+ hmac->data = tmp;
+}
+
+
+static void HmacCaviumSetKey(Hmac* hmac, int type, const byte* key,
+ word32 length)
+{
+ hmac->macType = (byte)type;
+ if (type == MD5)
+ hmac->type = MD5_TYPE;
+ else if (type == SHA)
+ hmac->type = SHA1_TYPE;
+ else if (type == SHA256)
+ hmac->type = SHA256_TYPE;
+ else {
+ WOLFSSL_MSG("unsupported cavium hmac type");
+ }
+
+ hmac->innerHashKeyed = 0; /* should we key Startup flag */
+
+ hmac->keyLen = (word16)length;
+ /* store key in ipad */
+ XMEMCPY(hmac->ipad, key, length);
+}
+
+#endif /* HAVE_CAVIUM */
+
+int wolfSSL_GetHmacMaxSize(void)
+{
+ return MAX_DIGEST_SIZE;
+}
+
+#ifdef HAVE_HKDF
+
+#ifndef WOLFSSL_HAVE_MIN
+#define WOLFSSL_HAVE_MIN
+
+ static INLINE word32 min(word32 a, word32 b)
+ {
+ return a > b ? b : a;
+ }
+
+#endif /* WOLFSSL_HAVE_MIN */
+
+
+static INLINE int GetHashSizeByType(int type)
+{
+ if (!(type == MD5 || type == SHA || type == SHA256 || type == SHA384
+ || type == SHA512 || type == BLAKE2B_ID))
+ return BAD_FUNC_ARG;
+
+ switch (type) {
+ #ifndef NO_MD5
+ case MD5:
+ return MD5_DIGEST_SIZE;
+ break;
+ #endif
+
+ #ifndef NO_SHA
+ case SHA:
+ return SHA_DIGEST_SIZE;
+ break;
+ #endif
+
+ #ifndef NO_SHA256
+ case SHA256:
+ return SHA256_DIGEST_SIZE;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA384
+ case SHA384:
+ return SHA384_DIGEST_SIZE;
+ break;
+ #endif
+
+ #ifdef WOLFSSL_SHA512
+ case SHA512:
+ return SHA512_DIGEST_SIZE;
+ break;
+ #endif
+
+ #ifdef HAVE_BLAKE2
+ case BLAKE2B_ID:
+ return BLAKE2B_OUTBYTES;
+ break;
+ #endif
+
+ default:
+ return BAD_FUNC_ARG;
+ break;
+ }
+}
+
+
+/* HMAC-KDF with hash type, optional salt and info, return 0 on success */
+int wc_HKDF(int type, const byte* inKey, word32 inKeySz,
+ const byte* salt, word32 saltSz,
+ const byte* info, word32 infoSz,
+ byte* out, word32 outSz)
+{
+ Hmac myHmac;
+#ifdef WOLFSSL_SMALL_STACK
+ byte* tmp;
+ byte* prk;
+#else
+ byte tmp[MAX_DIGEST_SIZE]; /* localSalt helper and T */
+ byte prk[MAX_DIGEST_SIZE];
+#endif
+ const byte* localSalt; /* either points to user input or tmp */
+ int hashSz = GetHashSizeByType(type);
+ word32 outIdx = 0;
+ byte n = 0x1;
+ int ret;
+
+ if (hashSz < 0)
+ return BAD_FUNC_ARG;
+
+#ifdef WOLFSSL_SMALL_STACK
+ tmp = (byte*)XMALLOC(MAX_DIGEST_SIZE, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+ if (tmp == NULL)
+ return MEMORY_E;
+
+ prk = (byte*)XMALLOC(MAX_DIGEST_SIZE, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+ if (prk == NULL) {
+ XFREE(tmp, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+ return MEMORY_E;
+ }
+#endif
+
+ localSalt = salt;
+ if (localSalt == NULL) {
+ XMEMSET(tmp, 0, hashSz);
+ localSalt = tmp;
+ saltSz = hashSz;
+ }
+
+ do {
+ ret = wc_HmacSetKey(&myHmac, type, localSalt, saltSz);
+ if (ret != 0)
+ break;
+ ret = wc_HmacUpdate(&myHmac, inKey, inKeySz);
+ if (ret != 0)
+ break;
+ ret = wc_HmacFinal(&myHmac, prk);
+ } while (0);
+
+ if (ret == 0) {
+ while (outIdx < outSz) {
+ int tmpSz = (n == 1) ? 0 : hashSz;
+ word32 left = outSz - outIdx;
+
+ ret = wc_HmacSetKey(&myHmac, type, prk, hashSz);
+ if (ret != 0)
+ break;
+ ret = wc_HmacUpdate(&myHmac, tmp, tmpSz);
+ if (ret != 0)
+ break;
+ ret = wc_HmacUpdate(&myHmac, info, infoSz);
+ if (ret != 0)
+ break;
+ ret = wc_HmacUpdate(&myHmac, &n, 1);
+ if (ret != 0)
+ break;
+ ret = wc_HmacFinal(&myHmac, tmp);
+ if (ret != 0)
+ break;
+
+ left = min(left, (word32)hashSz);
+ XMEMCPY(out+outIdx, tmp, left);
+
+ outIdx += hashSz;
+ n++;
+ }
+ }
+
+#ifdef WOLFSSL_SMALL_STACK
+ XFREE(tmp, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+ XFREE(prk, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
+
+ return ret;
+}
+
+#endif /* HAVE_HKDF */
+
+#endif /* HAVE_FIPS */
+#endif /* NO_HMAC */
+
+