Added new signature wrapper functions to allow direct use of hash wc_SignatureVerifyHash and wc_SignatureGenerateHash. These new function abstract existing signature wrapper code, so minimal code size increase. Added test cases for new functions for RSA (with and without DER encoding) and ECC.

wolfcrypt/src/signature.c

@@ -63,6 +63,7 @@ static int wc_SignatureDerEncode(enum wc_HashType hash_type, byte** hash_data,
             ret = wc_EncodeSignature(digest_buf, *hash_data, *hash_len, oid);
             if (ret > 0) {
                 digest_len = ret;
+                ret = 0;
 
                 /* Replace hash with digest (DER encoding + hash) */
                 XFREE(*hash_data, NULL, DYNAMIC_TYPE_TMP_BUFFER);
@@ -93,7 +94,7 @@ int wc_SignatureGetSize(enum wc_SignatureType sig_type,
     switch(sig_type) {
         case WC_SIGNATURE_TYPE_ECC:
 #ifdef HAVE_ECC
-            /* Santity check that void* key is at least ecc_key in size */
+            /* Sanity check that void* key is at least ecc_key in size */
             if (key_len >= sizeof(ecc_key)) {
                 sig_len = wc_ecc_sig_size((ecc_key*)key);
             }
@@ -108,7 +109,7 @@ int wc_SignatureGetSize(enum wc_SignatureType sig_type,
         case WC_SIGNATURE_TYPE_RSA_W_ENC:
         case WC_SIGNATURE_TYPE_RSA:
 #ifndef NO_RSA
-            /* Santity check that void* key is at least RsaKey in size */
+            /* Sanity check that void* key is at least RsaKey in size */
             if (key_len >= sizeof(RsaKey)) {
                 sig_len = wc_RsaEncryptSize((RsaKey*)key);
             }
@@ -128,18 +129,17 @@ int wc_SignatureGetSize(enum wc_SignatureType sig_type,
     return sig_len;
 }
 
-int wc_SignatureVerify(
+int wc_SignatureVerifyHash(
     enum wc_HashType hash_type, enum wc_SignatureType sig_type,
-    const byte* data, word32 data_len,
+    const byte* hash_data, word32 hash_len,
     const byte* sig, word32 sig_len,
     const void* key, word32 key_len)
 {
     int ret;
-    word32 hash_len;
-    byte *hash_data = NULL;
 
     /* Check arguments */
-    if (data == NULL || data_len <= 0 || sig == NULL || sig_len <= 0 ||
+    if (hash_data == NULL || hash_len <= 0 ||
+        sig == NULL || sig_len <= 0 ||
         key == NULL || key_len <= 0) {
         return BAD_FUNC_ARG;
     }
@@ -156,18 +156,9 @@ int wc_SignatureVerify(
         WOLFSSL_MSG("wc_SignatureVerify: Invalid hash type/len");
         return ret;
     }
-    hash_len = ret;
+    ret = 0;
 
-    /* Allocate temporary buffer for hash data */
+    /* Verify signature using hash */
-    hash_data = (byte*)XMALLOC(hash_len, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-    if (hash_data == NULL) {
-        return MEMORY_E;
-    }
-
-    /* Perform hash of data */
-    ret = wc_Hash(hash_type, data, data_len, hash_data, hash_len);
-    if(ret == 0) {
-        /* Verify signature using hash as data */
     switch (sig_type) {
         case WC_SIGNATURE_TYPE_ECC:
         {
@@ -194,20 +185,6 @@ int wc_SignatureVerify(
         }
 
         case WC_SIGNATURE_TYPE_RSA_W_ENC:
-#if defined(NO_RSA) || defined(NO_ASN)
-                ret = SIG_TYPE_E;
-                break;
-#else
-                ret = wc_SignatureDerEncode(hash_type, &hash_data, &hash_len);
-                /* Check for error */
-                if (ret < 0) {
-                    break;
-                }
-                /* Otherwise fall-through and perform normal RSA verify against updated
-                 * DER encoding + hash */
-#endif
-                FALL_THROUGH;
-
         case WC_SIGNATURE_TYPE_RSA:
         {
 #ifndef NO_RSA
@@ -256,6 +233,64 @@ int wc_SignatureVerify(
             ret = BAD_FUNC_ARG;
             break;
     }
+
+    return ret;
+}
+
+int wc_SignatureVerify(
+    enum wc_HashType hash_type, enum wc_SignatureType sig_type,
+    const byte* data, word32 data_len,
+    const byte* sig, word32 sig_len,
+    const void* key, word32 key_len)
+{
+    int ret;
+    word32 hash_len;
+    byte *hash_data = NULL;
+
+    /* Check arguments */
+    if (data == NULL || data_len <= 0 ||
+        sig == NULL || sig_len <= 0 ||
+        key == NULL || key_len <= 0) {
+        return BAD_FUNC_ARG;
+    }
+
+    /* Validate signature len (1 to max is okay) */
+    if ((int)sig_len > wc_SignatureGetSize(sig_type, key, key_len)) {
+        WOLFSSL_MSG("wc_SignatureVerify: Invalid sig type/len");
+        return BAD_FUNC_ARG;
+    }
+
+    /* Validate hash size */
+    ret = wc_HashGetDigestSize(hash_type);
+    if (ret < 0) {
+        WOLFSSL_MSG("wc_SignatureVerify: Invalid hash type/len");
+        return ret;
+    }
+    hash_len = ret;
+
+    /* Allocate temporary buffer for hash data */
+    hash_data = (byte*)XMALLOC(hash_len, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+    if (hash_data == NULL) {
+        return MEMORY_E;
+    }
+
+    /* Perform hash of data */
+    ret = wc_Hash(hash_type, data, data_len, hash_data, hash_len);
+    if (ret == 0) {
+        /* Handle RSA with DER encoding */
+        if (sig_type == WC_SIGNATURE_TYPE_RSA_W_ENC) {
+        #if defined(NO_RSA) || defined(NO_ASN)
+            ret = SIG_TYPE_E;
+        #else
+            ret = wc_SignatureDerEncode(hash_type, &hash_data, &hash_len);
+        #endif
+        }
+
+        if (ret == 0) {
+            /* Verify signature using hash */
+            ret = wc_SignatureVerifyHash(hash_type, sig_type,
+                hash_data, hash_len, sig, sig_len, key, key_len);
+        }
     }
 
     if (hash_data) {
@@ -265,22 +300,22 @@ int wc_SignatureVerify(
     return ret;
 }
 
-int wc_SignatureGenerate(
+
+int wc_SignatureGenerateHash(
     enum wc_HashType hash_type, enum wc_SignatureType sig_type,
-    const byte* data, word32 data_len,
+    const byte* hash_data, word32 hash_len,
     byte* sig, word32 *sig_len,
     const void* key, word32 key_len, WC_RNG* rng)
 {
     int ret;
-    word32 hash_len;
-    byte *hash_data = NULL;
 
     /* Suppress possible unused arg if all signature types are disabled */
     (void)rng;
 
     /* Check arguments */
-    if (data == NULL || data_len <= 0 || sig == NULL || sig_len == NULL ||
+    if (hash_data == NULL || hash_len <= 0 ||
-        *sig_len <= 0 || key == NULL || key_len <= 0) {
+        sig == NULL || sig_len == NULL || *sig_len <= 0 ||
+        key == NULL || key_len <= 0) {
         return BAD_FUNC_ARG;
     }
 
@@ -296,17 +331,8 @@ int wc_SignatureGenerate(
         WOLFSSL_MSG("wc_SignatureGenerate: Invalid hash type/len");
         return ret;
     }
-    hash_len = ret;
+    ret = 0;
 
-    /* Allocate temporary buffer for hash data */
-    hash_data = (byte*)XMALLOC(hash_len, NULL, DYNAMIC_TYPE_TMP_BUFFER);
-    if (hash_data == NULL) {
-        return MEMORY_E;
-    }
-
-    /* Perform hash of data */
-    ret = wc_Hash(hash_type, data, data_len, hash_data, hash_len);
-    if (ret == 0) {
     /* Create signature using hash as data */
     switch (sig_type) {
         case WC_SIGNATURE_TYPE_ECC:
@@ -327,19 +353,6 @@ int wc_SignatureGenerate(
             break;
 
         case WC_SIGNATURE_TYPE_RSA_W_ENC:
-#if defined(NO_RSA) || defined(NO_ASN)
-                ret = SIG_TYPE_E;
-                break;
-#else
-                ret = wc_SignatureDerEncode(hash_type, &hash_data, &hash_len);
-                /* Check for error */
-                if (ret < 0) {
-                    break;
-                }
-                /* Otherwise fall-through and perform normal RSA sign against updated
-                 * DER encoding + hash */
-#endif
-                FALL_THROUGH;
         case WC_SIGNATURE_TYPE_RSA:
 #ifndef NO_RSA
             /* Create signature using provided RSA key */
@@ -366,6 +379,64 @@ int wc_SignatureGenerate(
             ret = BAD_FUNC_ARG;
             break;
     }
+
+    return ret;
+}
+
+int wc_SignatureGenerate(
+    enum wc_HashType hash_type, enum wc_SignatureType sig_type,
+    const byte* data, word32 data_len,
+    byte* sig, word32 *sig_len,
+    const void* key, word32 key_len, WC_RNG* rng)
+{
+    int ret;
+    word32 hash_len;
+    byte *hash_data = NULL;
+
+    /* Check arguments */
+    if (data == NULL || data_len <= 0 ||
+        sig == NULL || sig_len == NULL || *sig_len <= 0 ||
+        key == NULL || key_len <= 0) {
+        return BAD_FUNC_ARG;
+    }
+
+    /* Validate signature len (needs to be at least max) */
+    if ((int)*sig_len < wc_SignatureGetSize(sig_type, key, key_len)) {
+        WOLFSSL_MSG("wc_SignatureGenerate: Invalid sig type/len");
+        return BAD_FUNC_ARG;
+    }
+
+    /* Validate hash size */
+    ret = wc_HashGetDigestSize(hash_type);
+    if (ret < 0) {
+        WOLFSSL_MSG("wc_SignatureGenerate: Invalid hash type/len");
+        return ret;
+    }
+    hash_len = ret;
+
+    /* Allocate temporary buffer for hash data */
+    hash_data = (byte*)XMALLOC(hash_len, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+    if (hash_data == NULL) {
+        return MEMORY_E;
+    }
+
+    /* Perform hash of data */
+    ret = wc_Hash(hash_type, data, data_len, hash_data, hash_len);
+    if (ret == 0) {
+        /* Handle RSA with DER encoding */
+        if (sig_type == WC_SIGNATURE_TYPE_RSA_W_ENC) {
+        #if defined(NO_RSA) || defined(NO_ASN)
+            ret = SIG_TYPE_E;
+        #else
+            ret = wc_SignatureDerEncode(hash_type, &hash_data, &hash_len);
+        #endif
+        }
+
+        if (ret == 0) {
+            /* Generate signature using hash */
+            ret = wc_SignatureGenerateHash(hash_type, sig_type,
+                hash_data, hash_len, sig, sig_len, key, key_len, rng);
+        }
     }
 
     if (hash_data) {

wolfcrypt/test/test.c

@@ -8205,7 +8205,23 @@ static int rsa_sig_test(RsaKey* key, word32 keyLen, int modLen, WC_RNG* rng)
 {
     int ret;
     word32 sigSz;
-    byte   in[] = "Everyone gets Friday off.";
+    const byte in[] = "Everyone gets Friday off.";
+    const byte hash[] = {
+        0xf2, 0x02, 0x95, 0x65, 0xcb, 0xf6, 0x2a, 0x59,
+        0x39, 0x2c, 0x05, 0xff, 0x0e, 0x29, 0xaf, 0xfe,
+        0x47, 0x33, 0x8c, 0x99, 0x8d, 0x58, 0x64, 0x83,
+        0xa6, 0x58, 0x0a, 0x33, 0x0b, 0x84, 0x5f, 0x5f
+    };
+    const byte hashEnc[] = {
+        0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86,
+        0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05,
+        0x00, 0x04, 0x20,
+
+        0xf2, 0x02, 0x95, 0x65, 0xcb, 0xf6, 0x2a, 0x59,
+        0x39, 0x2c, 0x05, 0xff, 0x0e, 0x29, 0xaf, 0xfe,
+        0x47, 0x33, 0x8c, 0x99, 0x8d, 0x58, 0x64, 0x83,
+        0xa6, 0x58, 0x0a, 0x33, 0x0b, 0x84, 0x5f, 0x5f
+    };
     word32 inLen = (word32)XSTRLEN((char*)in);
     byte   out[256];
 
@@ -8316,7 +8332,7 @@ static int rsa_sig_test(RsaKey* key, word32 keyLen, int modLen, WC_RNG* rng)
     if (ret != 0)
         return -5358;
 
-    sigSz = sizeof(out);
+    sigSz = (word32)sizeof(out);
     ret = wc_SignatureGenerate(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_RSA_W_ENC,
                                in, inLen, out, &sigSz, key, keyLen, rng);
     if (ret != 0)
@@ -8333,6 +8349,30 @@ static int rsa_sig_test(RsaKey* key, word32 keyLen, int modLen, WC_RNG* rng)
     if (ret == 0)
         return -5361;
 
+
+    /* check hash functions */
+    sigSz = (word32)sizeof(out);
+    ret = wc_SignatureGenerateHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_RSA,
+        hash, (int)sizeof(hash), out, &sigSz, key, keyLen, rng);
+    if (ret != 0)
+        return -5362;
+
+    ret = wc_SignatureVerifyHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_RSA,
+        hash, (int)sizeof(hash), out, (word32)modLen, key, keyLen);
+    if (ret != 0)
+        return -5363;
+
+    sigSz = (word32)sizeof(out);
+    ret = wc_SignatureGenerateHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_RSA_W_ENC,
+        hashEnc, (int)sizeof(hashEnc), out, &sigSz, key, keyLen, rng);
+    if (ret != 0)
+        return -5364;
+
+    ret = wc_SignatureVerifyHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_RSA_W_ENC,
+        hashEnc, (int)sizeof(hashEnc), out, (word32)modLen, key, keyLen);
+    if (ret != 0)
+        return -5365;
+
     return 0;
 }
 #endif /* !NO_SIG_WRAPPER */
@@ -14590,24 +14630,41 @@ static int ecc_sig_test(WC_RNG* rng, ecc_key* key)
     int     size;
     byte    out[ECC_MAX_SIG_SIZE];
     byte    in[] = "Everyone gets Friday off.";
+    const byte hash[] = {
+        0xf2, 0x02, 0x95, 0x65, 0xcb, 0xf6, 0x2a, 0x59,
+        0x39, 0x2c, 0x05, 0xff, 0x0e, 0x29, 0xaf, 0xfe,
+        0x47, 0x33, 0x8c, 0x99, 0x8d, 0x58, 0x64, 0x83,
+        0xa6, 0x58, 0x0a, 0x33, 0x0b, 0x84, 0x5f, 0x5f
+    };
     word32 inLen = (word32)XSTRLEN((char*)in);
 
     size = wc_ecc_sig_size(key);
 
     ret = wc_SignatureGetSize(WC_SIGNATURE_TYPE_ECC, key, sizeof(*key));
     if (ret != size)
-        return -6628;
+        return -6740;
 
     sigSz = (word32)ret;
     ret = wc_SignatureGenerate(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_ECC, in,
                                inLen, out, &sigSz, key, sizeof(*key), rng);
     if (ret != 0)
-        return -6629;
+        return -6741;
 
     ret = wc_SignatureVerify(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_ECC, in,
                              inLen, out, sigSz, key, sizeof(*key));
     if (ret != 0)
-        return -6630;
+        return -6742;
+
+    sigSz = (word32)sizeof(out);
+    ret = wc_SignatureGenerateHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_ECC,
+        hash, (int)sizeof(hash), out, &sigSz, key, sizeof(*key), rng);
+    if (ret != 0)
+        return -6743;
+
+    ret = wc_SignatureVerifyHash(WC_HASH_TYPE_SHA256, WC_SIGNATURE_TYPE_ECC,
+        hash, (int)sizeof(hash), out, sigSz, key, sizeof(*key));
+    if (ret != 0)
+        return -6744;
 
     return 0;
 }

wolfssl/wolfcrypt/signature.h

@@ -45,12 +45,23 @@ enum wc_SignatureType {
 WOLFSSL_API int wc_SignatureGetSize(enum wc_SignatureType sig_type,
     const void* key, word32 key_len);
 
+WOLFSSL_API int wc_SignatureVerifyHash(
+    enum wc_HashType hash_type, enum wc_SignatureType sig_type,
+    const byte* hash_data, word32 hash_len,
+    const byte* sig, word32 sig_len,
+    const void* key, word32 key_len);
+
 WOLFSSL_API int wc_SignatureVerify(
     enum wc_HashType hash_type, enum wc_SignatureType sig_type,
     const byte* data, word32 data_len,
     const byte* sig, word32 sig_len,
     const void* key, word32 key_len);
 
+WOLFSSL_API int wc_SignatureGenerateHash(
+    enum wc_HashType hash_type, enum wc_SignatureType sig_type,
+    const byte* hash_data, word32 hash_len,
+    byte* sig, word32 *sig_len,
+    const void* key, word32 key_len, WC_RNG* rng);
 WOLFSSL_API int wc_SignatureGenerate(
     enum wc_HashType hash_type, enum wc_SignatureType sig_type,
     const byte* data, word32 data_len,