Index: nss/lib/freebl/rsapkcs.c |
=================================================================== |
--- nss/lib/freebl/rsapkcs.c (revision 0) |
+++ nss/lib/freebl/rsapkcs.c (working copy) |
@@ -0,0 +1,1382 @@ |
+/* 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/. */ |
+ |
+/* |
+ * RSA PKCS#1 v2.1 (RFC 3447) operations |
+ */ |
+ |
+#ifdef FREEBL_NO_DEPEND |
+#include "stubs.h" |
+#endif |
+ |
+#include "secerr.h" |
+ |
+#include "blapi.h" |
+#include "secitem.h" |
+#include "blapii.h" |
+ |
+#define RSA_BLOCK_MIN_PAD_LEN 8 |
+#define RSA_BLOCK_FIRST_OCTET 0x00 |
+#define RSA_BLOCK_PRIVATE_PAD_OCTET 0xff |
+#define RSA_BLOCK_AFTER_PAD_OCTET 0x00 |
+ |
+/* |
+ * RSA block types |
+ * |
+ * The actual values are important -- they are fixed, *not* arbitrary. |
+ * The explicit value assignments are not needed (because C would give |
+ * us those same values anyway) but are included as a reminder... |
+ */ |
+typedef enum { |
+ RSA_BlockUnused = 0, /* unused */ |
+ RSA_BlockPrivate = 1, /* pad for a private-key operation */ |
+ RSA_BlockPublic = 2, /* pad for a public-key operation */ |
+ RSA_BlockRaw = 4, /* simply justify the block appropriately */ |
+ RSA_BlockTotal |
+} RSA_BlockType; |
+ |
+/* Needed for RSA-PSS functions */ |
+static const unsigned char eightZeros[] = { 0, 0, 0, 0, 0, 0, 0, 0 }; |
+ |
+/* Constant time comparison of a single byte. |
+ * Returns 1 iff a == b, otherwise returns 0. |
+ * Note: For ranges of bytes, use constantTimeCompare. |
+ */ |
+static unsigned char constantTimeEQ8(unsigned char a, unsigned char b) { |
+ unsigned char c = ~((a - b) | (b - a)); |
+ c >>= 7; |
+ return c; |
+} |
+ |
+/* Constant time comparison of a range of bytes. |
+ * Returns 1 iff len bytes of a are identical to len bytes of b, otherwise |
+ * returns 0. |
+ */ |
+static unsigned char constantTimeCompare(const unsigned char *a, |
+ const unsigned char *b, |
+ unsigned int len) { |
+ unsigned char tmp = 0; |
+ unsigned int i; |
+ for (i = 0; i < len; ++i, ++a, ++b) |
+ tmp |= *a ^ *b; |
+ return constantTimeEQ8(0x00, tmp); |
+} |
+ |
+/* Constant time conditional. |
+ * Returns a if c is 1, or b if c is 0. The result is undefined if c is |
+ * not 0 or 1. |
+ */ |
+static unsigned int constantTimeCondition(unsigned int c, |
+ unsigned int a, |
+ unsigned int b) |
+{ |
+ return (~(c - 1) & a) | ((c - 1) & b); |
+} |
+ |
+static unsigned int |
+rsa_modulusLen(SECItem * modulus) |
+{ |
+ unsigned char byteZero = modulus->data[0]; |
+ unsigned int modLen = modulus->len - !byteZero; |
+ return modLen; |
+} |
+ |
+/* |
+ * Format one block of data for public/private key encryption using |
+ * the rules defined in PKCS #1. |
+ */ |
+static unsigned char * |
+rsa_FormatOneBlock(unsigned modulusLen, |
+ RSA_BlockType blockType, |
+ SECItem * data) |
+{ |
+ unsigned char *block; |
+ unsigned char *bp; |
+ int padLen; |
+ int i, j; |
+ SECStatus rv; |
+ |
+ block = (unsigned char *) PORT_Alloc(modulusLen); |
+ if (block == NULL) |
+ return NULL; |
+ |
+ bp = block; |
+ |
+ /* |
+ * All RSA blocks start with two octets: |
+ * 0x00 || BlockType |
+ */ |
+ *bp++ = RSA_BLOCK_FIRST_OCTET; |
+ *bp++ = (unsigned char) blockType; |
+ |
+ switch (blockType) { |
+ |
+ /* |
+ * Blocks intended for private-key operation. |
+ */ |
+ case RSA_BlockPrivate: /* preferred method */ |
+ /* |
+ * 0x00 || BT || Pad || 0x00 || ActualData |
+ * 1 1 padLen 1 data->len |
+ * Pad is either all 0x00 or all 0xff bytes, depending on blockType. |
+ */ |
+ padLen = modulusLen - data->len - 3; |
+ PORT_Assert(padLen >= RSA_BLOCK_MIN_PAD_LEN); |
+ if (padLen < RSA_BLOCK_MIN_PAD_LEN) { |
+ PORT_Free(block); |
+ return NULL; |
+ } |
+ PORT_Memset(bp, RSA_BLOCK_PRIVATE_PAD_OCTET, padLen); |
+ bp += padLen; |
+ *bp++ = RSA_BLOCK_AFTER_PAD_OCTET; |
+ PORT_Memcpy(bp, data->data, data->len); |
+ break; |
+ |
+ /* |
+ * Blocks intended for public-key operation. |
+ */ |
+ case RSA_BlockPublic: |
+ /* |
+ * 0x00 || BT || Pad || 0x00 || ActualData |
+ * 1 1 padLen 1 data->len |
+ * Pad is all non-zero random bytes. |
+ * |
+ * Build the block left to right. |
+ * Fill the entire block from Pad to the end with random bytes. |
+ * Use the bytes after Pad as a supply of extra random bytes from |
+ * which to find replacements for the zero bytes in Pad. |
+ * If we need more than that, refill the bytes after Pad with |
+ * new random bytes as necessary. |
+ */ |
+ padLen = modulusLen - (data->len + 3); |
+ PORT_Assert(padLen >= RSA_BLOCK_MIN_PAD_LEN); |
+ if (padLen < RSA_BLOCK_MIN_PAD_LEN) { |
+ PORT_Free(block); |
+ return NULL; |
+ } |
+ j = modulusLen - 2; |
+ rv = RNG_GenerateGlobalRandomBytes(bp, j); |
+ if (rv == SECSuccess) { |
+ for (i = 0; i < padLen; ) { |
+ unsigned char repl; |
+ /* Pad with non-zero random data. */ |
+ if (bp[i] != RSA_BLOCK_AFTER_PAD_OCTET) { |
+ ++i; |
+ continue; |
+ } |
+ if (j <= padLen) { |
+ rv = RNG_GenerateGlobalRandomBytes(bp + padLen, |
+ modulusLen - (2 + padLen)); |
+ if (rv != SECSuccess) |
+ break; |
+ j = modulusLen - 2; |
+ } |
+ do { |
+ repl = bp[--j]; |
+ } while (repl == RSA_BLOCK_AFTER_PAD_OCTET && j > padLen); |
+ if (repl != RSA_BLOCK_AFTER_PAD_OCTET) { |
+ bp[i++] = repl; |
+ } |
+ } |
+ } |
+ if (rv != SECSuccess) { |
+ PORT_Free(block); |
+ PORT_SetError(SEC_ERROR_LIBRARY_FAILURE); |
+ return NULL; |
+ } |
+ bp += padLen; |
+ *bp++ = RSA_BLOCK_AFTER_PAD_OCTET; |
+ PORT_Memcpy(bp, data->data, data->len); |
+ break; |
+ |
+ default: |
+ PORT_Assert(0); |
+ PORT_Free(block); |
+ return NULL; |
+ } |
+ |
+ return block; |
+} |
+ |
+static SECStatus |
+rsa_FormatBlock(SECItem * result, |
+ unsigned modulusLen, |
+ RSA_BlockType blockType, |
+ SECItem * data) |
+{ |
+ switch (blockType) { |
+ case RSA_BlockPrivate: |
+ case RSA_BlockPublic: |
+ /* |
+ * 0x00 || BT || Pad || 0x00 || ActualData |
+ * |
+ * The "3" below is the first octet + the second octet + the 0x00 |
+ * octet that always comes just before the ActualData. |
+ */ |
+ PORT_Assert(data->len <= (modulusLen - (3 + RSA_BLOCK_MIN_PAD_LEN))); |
+ |
+ result->data = rsa_FormatOneBlock(modulusLen, blockType, data); |
+ if (result->data == NULL) { |
+ result->len = 0; |
+ return SECFailure; |
+ } |
+ result->len = modulusLen; |
+ |
+ break; |
+ |
+ case RSA_BlockRaw: |
+ /* |
+ * Pad || ActualData |
+ * Pad is zeros. The application is responsible for recovering |
+ * the actual data. |
+ */ |
+ if (data->len > modulusLen ) { |
+ return SECFailure; |
+ } |
+ result->data = (unsigned char*)PORT_ZAlloc(modulusLen); |
+ result->len = modulusLen; |
+ PORT_Memcpy(result->data + (modulusLen - data->len), |
+ data->data, data->len); |
+ break; |
+ |
+ default: |
+ PORT_Assert(0); |
+ result->data = NULL; |
+ result->len = 0; |
+ return SECFailure; |
+ } |
+ |
+ return SECSuccess; |
+} |
+ |
+/* |
+ * Mask generation function MGF1 as defined in PKCS #1 v2.1 / RFC 3447. |
+ */ |
+static SECStatus |
+MGF1(HASH_HashType hashAlg, |
+ unsigned char * mask, |
+ unsigned int maskLen, |
+ const unsigned char * mgfSeed, |
+ unsigned int mgfSeedLen) |
+{ |
+ unsigned int digestLen; |
+ PRUint32 counter; |
+ PRUint32 rounds; |
+ unsigned char * tempHash; |
+ unsigned char * temp; |
+ const SECHashObject * hash; |
+ void * hashContext; |
+ unsigned char C[4]; |
+ |
+ hash = HASH_GetRawHashObject(hashAlg); |
+ if (hash == NULL) |
+ return SECFailure; |
+ |
+ hashContext = (*hash->create)(); |
+ rounds = (maskLen + hash->length - 1) / hash->length; |
+ for (counter = 0; counter < rounds; counter++) { |
+ C[0] = (unsigned char)((counter >> 24) & 0xff); |
+ C[1] = (unsigned char)((counter >> 16) & 0xff); |
+ C[2] = (unsigned char)((counter >> 8) & 0xff); |
+ C[3] = (unsigned char)(counter & 0xff); |
+ |
+ /* This could be optimized when the clone functions in |
+ * rawhash.c are implemented. */ |
+ (*hash->begin)(hashContext); |
+ (*hash->update)(hashContext, mgfSeed, mgfSeedLen); |
+ (*hash->update)(hashContext, C, sizeof C); |
+ |
+ tempHash = mask + counter * hash->length; |
+ if (counter != (rounds - 1)) { |
+ (*hash->end)(hashContext, tempHash, &digestLen, hash->length); |
+ } else { /* we're in the last round and need to cut the hash */ |
+ temp = (unsigned char *)PORT_Alloc(hash->length); |
+ (*hash->end)(hashContext, temp, &digestLen, hash->length); |
+ PORT_Memcpy(tempHash, temp, maskLen - counter * hash->length); |
+ PORT_Free(temp); |
+ } |
+ } |
+ (*hash->destroy)(hashContext, PR_TRUE); |
+ |
+ return SECSuccess; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_SignRaw(RSAPrivateKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * data, |
+ unsigned int dataLen) |
+{ |
+ SECStatus rv = SECSuccess; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ SECItem formatted; |
+ SECItem unformatted; |
+ |
+ if (maxOutputLen < modulusLen) |
+ return SECFailure; |
+ |
+ unformatted.len = dataLen; |
+ unformatted.data = (unsigned char*)data; |
+ formatted.data = NULL; |
+ rv = rsa_FormatBlock(&formatted, modulusLen, RSA_BlockRaw, &unformatted); |
+ if (rv != SECSuccess) |
+ goto done; |
+ |
+ rv = RSA_PrivateKeyOpDoubleChecked(key, output, formatted.data); |
+ *outputLen = modulusLen; |
+ |
+done: |
+ if (formatted.data != NULL) |
+ PORT_ZFree(formatted.data, modulusLen); |
+ return rv; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_CheckSignRaw(RSAPublicKey * key, |
+ const unsigned char * sig, |
+ unsigned int sigLen, |
+ const unsigned char * hash, |
+ unsigned int hashLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned char * buffer; |
+ |
+ if (sigLen != modulusLen) |
+ goto failure; |
+ if (hashLen > modulusLen) |
+ goto failure; |
+ |
+ buffer = (unsigned char *)PORT_Alloc(modulusLen + 1); |
+ if (!buffer) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, buffer, sig); |
+ if (rv != SECSuccess) |
+ goto loser; |
+ |
+ /* |
+ * make sure we get the same results |
+ */ |
+ /* XXX(rsleevi): Constant time */ |
+ /* NOTE: should we verify the leading zeros? */ |
+ if (PORT_Memcmp(buffer + (modulusLen - hashLen), hash, hashLen) != 0) |
+ goto loser; |
+ |
+ PORT_Free(buffer); |
+ return SECSuccess; |
+ |
+loser: |
+ PORT_Free(buffer); |
+failure: |
+ return SECFailure; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_CheckSignRecoverRaw(RSAPublicKey * key, |
+ unsigned char * data, |
+ unsigned int * dataLen, |
+ unsigned int maxDataLen, |
+ const unsigned char * sig, |
+ unsigned int sigLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ |
+ if (sigLen != modulusLen) |
+ goto failure; |
+ if (maxDataLen < modulusLen) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, data, sig); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ *dataLen = modulusLen; |
+ return SECSuccess; |
+ |
+failure: |
+ return SECFailure; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_EncryptRaw(RSAPublicKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ SECItem formatted; |
+ SECItem unformatted; |
+ |
+ formatted.data = NULL; |
+ if (maxOutputLen < modulusLen) |
+ goto failure; |
+ |
+ unformatted.len = inputLen; |
+ unformatted.data = (unsigned char*)input; |
+ formatted.data = NULL; |
+ rv = rsa_FormatBlock(&formatted, modulusLen, RSA_BlockRaw, &unformatted); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, output, formatted.data); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ PORT_ZFree(formatted.data, modulusLen); |
+ *outputLen = modulusLen; |
+ return SECSuccess; |
+ |
+failure: |
+ if (formatted.data != NULL) |
+ PORT_ZFree(formatted.data, modulusLen); |
+ return SECFailure; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_DecryptRaw(RSAPrivateKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ |
+ if (modulusLen > maxOutputLen) |
+ goto failure; |
+ if (inputLen != modulusLen) |
+ goto failure; |
+ |
+ rv = RSA_PrivateKeyOp(key, output, input); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ *outputLen = modulusLen; |
+ return SECSuccess; |
+ |
+failure: |
+ return SECFailure; |
+} |
+ |
+/* |
+ * Decodes an EME-OAEP encoded block, validating the encoding in constant |
+ * time. |
+ * Described in RFC 3447, section 7.1.2. |
+ * input contains the encoded block, after decryption. |
+ * label is the optional value L that was associated with the message. |
+ * On success, the original message and message length will be stored in |
+ * output and outputLen. |
+ */ |
+static SECStatus |
+eme_oaep_decode(unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * label, |
+ unsigned int labelLen) |
+{ |
+ const SECHashObject * hash; |
+ void * hashContext; |
+ SECStatus rv = SECFailure; |
+ unsigned char labelHash[HASH_LENGTH_MAX]; |
+ unsigned int i; |
+ unsigned int maskLen; |
+ unsigned int paddingOffset; |
+ unsigned char * mask = NULL; |
+ unsigned char * tmpOutput = NULL; |
+ unsigned char isGood; |
+ unsigned char foundPaddingEnd; |
+ |
+ hash = HASH_GetRawHashObject(hashAlg); |
+ |
+ /* 1.c */ |
+ if (inputLen < (hash->length * 2) + 2) { |
+ PORT_SetError(SEC_ERROR_INPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ /* Step 3.a - Generate lHash */ |
+ hashContext = (*hash->create)(); |
+ if (hashContext == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ (*hash->begin)(hashContext); |
+ if (labelLen > 0) |
+ (*hash->update)(hashContext, label, labelLen); |
+ (*hash->end)(hashContext, labelHash, &i, sizeof(labelHash)); |
+ (*hash->destroy)(hashContext, PR_TRUE); |
+ |
+ tmpOutput = (unsigned char*)PORT_Alloc(inputLen); |
+ if (tmpOutput == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ goto done; |
+ } |
+ |
+ maskLen = inputLen - hash->length - 1; |
+ mask = (unsigned char*)PORT_Alloc(maskLen); |
+ if (mask == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ goto done; |
+ } |
+ |
+ PORT_Memcpy(tmpOutput, input, inputLen); |
+ |
+ /* 3.c - Generate seedMask */ |
+ MGF1(maskHashAlg, mask, hash->length, &tmpOutput[1 + hash->length], |
+ inputLen - hash->length - 1); |
+ /* 3.d - Unmask seed */ |
+ for (i = 0; i < hash->length; ++i) |
+ tmpOutput[1 + i] ^= mask[i]; |
+ |
+ /* 3.e - Generate dbMask */ |
+ MGF1(maskHashAlg, mask, maskLen, &tmpOutput[1], hash->length); |
+ /* 3.f - Unmask DB */ |
+ for (i = 0; i < maskLen; ++i) |
+ tmpOutput[1 + hash->length + i] ^= mask[i]; |
+ |
+ /* 3.g - Compare Y, lHash, and PS in constant time |
+ * Warning: This code is timing dependent and must not disclose which of |
+ * these were invalid. |
+ */ |
+ paddingOffset = 0; |
+ isGood = 1; |
+ foundPaddingEnd = 0; |
+ |
+ /* Compare Y */ |
+ isGood &= constantTimeEQ8(0x00, tmpOutput[0]); |
+ |
+ /* Compare lHash and lHash' */ |
+ isGood &= constantTimeCompare(&labelHash[0], |
+ &tmpOutput[1 + hash->length], |
+ hash->length); |
+ |
+ /* Compare that the padding is zero or more zero octets, followed by a |
+ * 0x01 octet */ |
+ for (i = 1 + (hash->length * 2); i < inputLen; ++i) { |
+ unsigned char isZero = constantTimeEQ8(0x00, tmpOutput[i]); |
+ unsigned char isOne = constantTimeEQ8(0x01, tmpOutput[i]); |
+ /* non-constant time equivalent: |
+ * if (tmpOutput[i] == 0x01 && !foundPaddingEnd) |
+ * paddingOffset = i; |
+ */ |
+ paddingOffset = constantTimeCondition(isOne & ~foundPaddingEnd, i, |
+ paddingOffset); |
+ /* non-constant time equivalent: |
+ * if (tmpOutput[i] == 0x01) |
+ * foundPaddingEnd = true; |
+ * |
+ * Note: This may yield false positives, as it will be set whenever |
+ * a 0x01 byte is encountered. If there was bad padding (eg: |
+ * 0x03 0x02 0x01), foundPaddingEnd will still be set to true, and |
+ * paddingOffset will still be set to 2. |
+ */ |
+ foundPaddingEnd = constantTimeCondition(isOne, 1, foundPaddingEnd); |
+ /* non-constant time equivalent: |
+ * if (tmpOutput[i] != 0x00 && tmpOutput[i] != 0x01 && |
+ * !foundPaddingEnd) { |
+ * isGood = false; |
+ * } |
+ * |
+ * Note: This may yield false positives, as a message (and padding) |
+ * that is entirely zeros will result in isGood still being true. Thus |
+ * it's necessary to check foundPaddingEnd is positive below. |
+ */ |
+ isGood = constantTimeCondition(~foundPaddingEnd & ~isZero, 0, isGood); |
+ } |
+ |
+ /* While both isGood and foundPaddingEnd may have false positives, they |
+ * cannot BOTH have false positives. If both are not true, then an invalid |
+ * message was received. Note, this comparison must still be done in constant |
+ * time so as not to leak either condition. |
+ */ |
+ if (!(isGood & foundPaddingEnd)) { |
+ PORT_SetError(SEC_ERROR_BAD_DATA); |
+ goto done; |
+ } |
+ |
+ /* End timing dependent code */ |
+ |
+ ++paddingOffset; /* Skip the 0x01 following the end of PS */ |
+ |
+ *outputLen = inputLen - paddingOffset; |
+ if (*outputLen > maxOutputLen) { |
+ PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
+ goto done; |
+ } |
+ |
+ if (*outputLen) |
+ PORT_Memcpy(output, &tmpOutput[paddingOffset], *outputLen); |
+ rv = SECSuccess; |
+ |
+done: |
+ if (mask) |
+ PORT_ZFree(mask, maskLen); |
+ if (tmpOutput) |
+ PORT_ZFree(tmpOutput, inputLen); |
+ return rv; |
+} |
+ |
+/* |
+ * Generate an EME-OAEP encoded block for encryption |
+ * Described in RFC 3447, section 7.1.1 |
+ * We use input instead of M for the message to be encrypted |
+ * label is the optional value L to be associated with the message. |
+ */ |
+static SECStatus |
+eme_oaep_encode(unsigned char * em, |
+ unsigned int emLen, |
+ const unsigned char * input, |
+ unsigned int inputLen, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * label, |
+ unsigned int labelLen, |
+ const unsigned char * seed, |
+ unsigned int seedLen) |
+{ |
+ const SECHashObject * hash; |
+ void * hashContext; |
+ SECStatus rv; |
+ unsigned char * mask; |
+ unsigned int reservedLen; |
+ unsigned int dbMaskLen; |
+ unsigned int i; |
+ |
+ hash = HASH_GetRawHashObject(hashAlg); |
+ PORT_Assert(seed == NULL || seedLen == hash->length); |
+ |
+ /* Step 1.b */ |
+ reservedLen = (2 * hash->length) + 2; |
+ if (emLen < reservedLen || inputLen > (emLen - reservedLen)) { |
+ PORT_SetError(SEC_ERROR_INPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ /* |
+ * From RFC 3447, Section 7.1 |
+ * +----------+---------+-------+ |
+ * DB = | lHash | PS | M | |
+ * +----------+---------+-------+ |
+ * | |
+ * +----------+ V |
+ * | seed |--> MGF ---> xor |
+ * +----------+ | |
+ * | | |
+ * +--+ V | |
+ * |00| xor <----- MGF <-----| |
+ * +--+ | | |
+ * | | | |
+ * V V V |
+ * +--+----------+----------------------------+ |
+ * EM = |00|maskedSeed| maskedDB | |
+ * +--+----------+----------------------------+ |
+ * |
+ * We use mask to hold the result of the MGF functions, and all other |
+ * values are generated in their final resting place. |
+ */ |
+ *em = 0x00; |
+ |
+ /* Step 2.a - Generate lHash */ |
+ hashContext = (*hash->create)(); |
+ if (hashContext == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ (*hash->begin)(hashContext); |
+ if (labelLen > 0) |
+ (*hash->update)(hashContext, label, labelLen); |
+ (*hash->end)(hashContext, &em[1 + hash->length], &i, hash->length); |
+ (*hash->destroy)(hashContext, PR_TRUE); |
+ |
+ /* Step 2.b - Generate PS */ |
+ if (emLen - reservedLen - inputLen > 0) { |
+ PORT_Memset(em + 1 + (hash->length * 2), 0x00, |
+ emLen - reservedLen - inputLen); |
+ } |
+ |
+ /* Step 2.c. - Generate DB |
+ * DB = lHash || PS || 0x01 || M |
+ * Note that PS and lHash have already been placed into em at their |
+ * appropriate offsets. This just copies M into place |
+ */ |
+ em[emLen - inputLen - 1] = 0x01; |
+ if (inputLen) |
+ PORT_Memcpy(em + emLen - inputLen, input, inputLen); |
+ |
+ if (seed == NULL) { |
+ /* Step 2.d - Generate seed */ |
+ rv = RNG_GenerateGlobalRandomBytes(em + 1, hash->length); |
+ if (rv != SECSuccess) { |
+ return rv; |
+ } |
+ } else { |
+ /* For Known Answer Tests, copy the supplied seed. */ |
+ PORT_Memcpy(em + 1, seed, seedLen); |
+ } |
+ |
+ /* Step 2.e - Generate dbMask*/ |
+ dbMaskLen = emLen - hash->length - 1; |
+ mask = (unsigned char*)PORT_Alloc(dbMaskLen); |
+ if (mask == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ MGF1(maskHashAlg, mask, dbMaskLen, em + 1, hash->length); |
+ /* Step 2.f - Compute maskedDB*/ |
+ for (i = 0; i < dbMaskLen; ++i) |
+ em[1 + hash->length + i] ^= mask[i]; |
+ |
+ /* Step 2.g - Generate seedMask */ |
+ MGF1(maskHashAlg, mask, hash->length, &em[1 + hash->length], dbMaskLen); |
+ /* Step 2.h - Compute maskedSeed */ |
+ for (i = 0; i < hash->length; ++i) |
+ em[1 + i] ^= mask[i]; |
+ |
+ PORT_ZFree(mask, dbMaskLen); |
+ return SECSuccess; |
+} |
+ |
+SECStatus |
+RSA_EncryptOAEP(RSAPublicKey * key, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * label, |
+ unsigned int labelLen, |
+ const unsigned char * seed, |
+ unsigned int seedLen, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv = SECFailure; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned char * oaepEncoded = NULL; |
+ |
+ if (maxOutputLen < modulusLen) { |
+ PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ if ((hashAlg == HASH_AlgNULL) || (maskHashAlg == HASH_AlgNULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ if ((labelLen == 0 && label != NULL) || |
+ (labelLen > 0 && label == NULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ oaepEncoded = (unsigned char *)PORT_Alloc(modulusLen); |
+ if (oaepEncoded == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ rv = eme_oaep_encode(oaepEncoded, modulusLen, input, inputLen, |
+ hashAlg, maskHashAlg, label, labelLen, seed, seedLen); |
+ if (rv != SECSuccess) |
+ goto done; |
+ |
+ rv = RSA_PublicKeyOp(key, output, oaepEncoded); |
+ if (rv != SECSuccess) |
+ goto done; |
+ *outputLen = modulusLen; |
+ |
+done: |
+ PORT_Free(oaepEncoded); |
+ return rv; |
+} |
+ |
+SECStatus |
+RSA_DecryptOAEP(RSAPrivateKey * key, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * label, |
+ unsigned int labelLen, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv = SECFailure; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned char * oaepEncoded = NULL; |
+ |
+ if ((hashAlg == HASH_AlgNULL) || (maskHashAlg == HASH_AlgNULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ if (inputLen != modulusLen) { |
+ PORT_SetError(SEC_ERROR_INPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ if ((labelLen == 0 && label != NULL) || |
+ (labelLen > 0 && label == NULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ oaepEncoded = (unsigned char *)PORT_Alloc(modulusLen); |
+ if (oaepEncoded == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ |
+ rv = RSA_PrivateKeyOpDoubleChecked(key, oaepEncoded, input); |
+ if (rv != SECSuccess) { |
+ goto done; |
+ } |
+ rv = eme_oaep_decode(output, outputLen, maxOutputLen, oaepEncoded, |
+ modulusLen, hashAlg, maskHashAlg, label, |
+ labelLen); |
+ |
+done: |
+ if (oaepEncoded) |
+ PORT_ZFree(oaepEncoded, modulusLen); |
+ return rv; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_EncryptBlock(RSAPublicKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ SECItem formatted; |
+ SECItem unformatted; |
+ |
+ formatted.data = NULL; |
+ if (maxOutputLen < modulusLen) |
+ goto failure; |
+ |
+ unformatted.len = inputLen; |
+ unformatted.data = (unsigned char*)input; |
+ formatted.data = NULL; |
+ rv = rsa_FormatBlock(&formatted, modulusLen, RSA_BlockPublic, |
+ &unformatted); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, output, formatted.data); |
+ if (rv != SECSuccess) |
+ goto failure; |
+ |
+ PORT_ZFree(formatted.data, modulusLen); |
+ *outputLen = modulusLen; |
+ return SECSuccess; |
+ |
+failure: |
+ if (formatted.data != NULL) |
+ PORT_ZFree(formatted.data, modulusLen); |
+ return SECFailure; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_DecryptBlock(RSAPrivateKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned int i; |
+ unsigned char * buffer; |
+ |
+ if (inputLen != modulusLen) |
+ goto failure; |
+ |
+ buffer = (unsigned char *)PORT_Alloc(modulusLen + 1); |
+ if (!buffer) |
+ goto failure; |
+ |
+ rv = RSA_PrivateKeyOp(key, buffer, input); |
+ if (rv != SECSuccess) |
+ goto loser; |
+ |
+ /* XXX(rsleevi): Constant time */ |
+ if (buffer[0] != RSA_BLOCK_FIRST_OCTET || |
+ buffer[1] != (unsigned char)RSA_BlockPublic) { |
+ goto loser; |
+ } |
+ *outputLen = 0; |
+ for (i = 2; i < modulusLen; i++) { |
+ if (buffer[i] == RSA_BLOCK_AFTER_PAD_OCTET) { |
+ *outputLen = modulusLen - i - 1; |
+ break; |
+ } |
+ } |
+ if (*outputLen == 0) |
+ goto loser; |
+ if (*outputLen > maxOutputLen) |
+ goto loser; |
+ |
+ PORT_Memcpy(output, buffer + modulusLen - *outputLen, *outputLen); |
+ |
+ PORT_Free(buffer); |
+ return SECSuccess; |
+ |
+loser: |
+ PORT_Free(buffer); |
+failure: |
+ return SECFailure; |
+} |
+ |
+/* |
+ * Encode a RSA-PSS signature. |
+ * Described in RFC 3447, section 9.1.1. |
+ * We use mHash instead of M as input. |
+ * emBits from the RFC is just modBits - 1, see section 8.1.1. |
+ * We only support MGF1 as the MGF. |
+ * |
+ * NOTE: this code assumes modBits is a multiple of 8. |
+ */ |
+static SECStatus |
+emsa_pss_encode(unsigned char * em, |
+ unsigned int emLen, |
+ const unsigned char * mHash, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * salt, |
+ unsigned int saltLen) |
+{ |
+ const SECHashObject * hash; |
+ void * hash_context; |
+ unsigned char * dbMask; |
+ unsigned int dbMaskLen; |
+ unsigned int i; |
+ SECStatus rv; |
+ |
+ hash = HASH_GetRawHashObject(hashAlg); |
+ dbMaskLen = emLen - hash->length - 1; |
+ |
+ /* Step 3 */ |
+ if (emLen < hash->length + saltLen + 2) { |
+ PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ /* Step 4 */ |
+ if (salt == NULL) { |
+ rv = RNG_GenerateGlobalRandomBytes(&em[dbMaskLen - saltLen], saltLen); |
+ if (rv != SECSuccess) { |
+ return rv; |
+ } |
+ } else { |
+ PORT_Memcpy(&em[dbMaskLen - saltLen], salt, saltLen); |
+ } |
+ |
+ /* Step 5 + 6 */ |
+ /* Compute H and store it at its final location &em[dbMaskLen]. */ |
+ hash_context = (*hash->create)(); |
+ if (hash_context == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ (*hash->begin)(hash_context); |
+ (*hash->update)(hash_context, eightZeros, 8); |
+ (*hash->update)(hash_context, mHash, hash->length); |
+ (*hash->update)(hash_context, &em[dbMaskLen - saltLen], saltLen); |
+ (*hash->end)(hash_context, &em[dbMaskLen], &i, hash->length); |
+ (*hash->destroy)(hash_context, PR_TRUE); |
+ |
+ /* Step 7 + 8 */ |
+ PORT_Memset(em, 0, dbMaskLen - saltLen - 1); |
+ em[dbMaskLen - saltLen - 1] = 0x01; |
+ |
+ /* Step 9 */ |
+ dbMask = (unsigned char *)PORT_Alloc(dbMaskLen); |
+ if (dbMask == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ MGF1(maskHashAlg, dbMask, dbMaskLen, &em[dbMaskLen], hash->length); |
+ |
+ /* Step 10 */ |
+ for (i = 0; i < dbMaskLen; i++) |
+ em[i] ^= dbMask[i]; |
+ PORT_Free(dbMask); |
+ |
+ /* Step 11 */ |
+ em[0] &= 0x7f; |
+ |
+ /* Step 12 */ |
+ em[emLen - 1] = 0xbc; |
+ |
+ return SECSuccess; |
+} |
+ |
+/* |
+ * Verify a RSA-PSS signature. |
+ * Described in RFC 3447, section 9.1.2. |
+ * We use mHash instead of M as input. |
+ * emBits from the RFC is just modBits - 1, see section 8.1.2. |
+ * We only support MGF1 as the MGF. |
+ * |
+ * NOTE: this code assumes modBits is a multiple of 8. |
+ */ |
+static SECStatus |
+emsa_pss_verify(const unsigned char * mHash, |
+ const unsigned char * em, |
+ unsigned int emLen, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ unsigned int saltLen) |
+{ |
+ const SECHashObject * hash; |
+ void * hash_context; |
+ unsigned char * db; |
+ unsigned char * H_; /* H' from the RFC */ |
+ unsigned int i; |
+ unsigned int dbMaskLen; |
+ SECStatus rv; |
+ |
+ hash = HASH_GetRawHashObject(hashAlg); |
+ dbMaskLen = emLen - hash->length - 1; |
+ |
+ /* Step 3 + 4 + 6 */ |
+ if ((emLen < (hash->length + saltLen + 2)) || |
+ (em[emLen - 1] != 0xbc) || |
+ ((em[0] & 0x80) != 0)) { |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ return SECFailure; |
+ } |
+ |
+ /* Step 7 */ |
+ db = (unsigned char *)PORT_Alloc(dbMaskLen); |
+ if (db == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ /* &em[dbMaskLen] points to H, used as mgfSeed */ |
+ MGF1(maskHashAlg, db, dbMaskLen, &em[dbMaskLen], hash->length); |
+ |
+ /* Step 8 */ |
+ for (i = 0; i < dbMaskLen; i++) { |
+ db[i] ^= em[i]; |
+ } |
+ |
+ /* Step 9 */ |
+ db[0] &= 0x7f; |
+ |
+ /* Step 10 */ |
+ for (i = 0; i < (dbMaskLen - saltLen - 1); i++) { |
+ if (db[i] != 0) { |
+ PORT_Free(db); |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ return SECFailure; |
+ } |
+ } |
+ if (db[dbMaskLen - saltLen - 1] != 0x01) { |
+ PORT_Free(db); |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ return SECFailure; |
+ } |
+ |
+ /* Step 12 + 13 */ |
+ H_ = (unsigned char *)PORT_Alloc(hash->length); |
+ if (H_ == NULL) { |
+ PORT_Free(db); |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ hash_context = (*hash->create)(); |
+ if (hash_context == NULL) { |
+ PORT_Free(db); |
+ PORT_Free(H_); |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ (*hash->begin)(hash_context); |
+ (*hash->update)(hash_context, eightZeros, 8); |
+ (*hash->update)(hash_context, mHash, hash->length); |
+ (*hash->update)(hash_context, &db[dbMaskLen - saltLen], saltLen); |
+ (*hash->end)(hash_context, H_, &i, hash->length); |
+ (*hash->destroy)(hash_context, PR_TRUE); |
+ |
+ PORT_Free(db); |
+ |
+ /* Step 14 */ |
+ if (PORT_Memcmp(H_, &em[dbMaskLen], hash->length) != 0) { |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ rv = SECFailure; |
+ } else { |
+ rv = SECSuccess; |
+ } |
+ |
+ PORT_Free(H_); |
+ return rv; |
+} |
+ |
+SECStatus |
+RSA_SignPSS(RSAPrivateKey * key, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ const unsigned char * salt, |
+ unsigned int saltLength, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv = SECSuccess; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned char *pssEncoded = NULL; |
+ |
+ if (maxOutputLen < modulusLen) { |
+ PORT_SetError(SEC_ERROR_OUTPUT_LEN); |
+ return SECFailure; |
+ } |
+ |
+ if ((hashAlg == HASH_AlgNULL) || (maskHashAlg == HASH_AlgNULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ pssEncoded = (unsigned char *)PORT_Alloc(modulusLen); |
+ if (pssEncoded == NULL) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ rv = emsa_pss_encode(pssEncoded, modulusLen, input, hashAlg, |
+ maskHashAlg, salt, saltLength); |
+ if (rv != SECSuccess) |
+ goto done; |
+ |
+ rv = RSA_PrivateKeyOpDoubleChecked(key, output, pssEncoded); |
+ *outputLen = modulusLen; |
+ |
+done: |
+ PORT_Free(pssEncoded); |
+ return rv; |
+} |
+ |
+SECStatus |
+RSA_CheckSignPSS(RSAPublicKey * key, |
+ HASH_HashType hashAlg, |
+ HASH_HashType maskHashAlg, |
+ unsigned int saltLength, |
+ const unsigned char * sig, |
+ unsigned int sigLen, |
+ const unsigned char * hash, |
+ unsigned int hashLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned char * buffer; |
+ |
+ if (sigLen != modulusLen) { |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ return SECFailure; |
+ } |
+ |
+ if ((hashAlg == HASH_AlgNULL) || (maskHashAlg == HASH_AlgNULL)) { |
+ PORT_SetError(SEC_ERROR_INVALID_ALGORITHM); |
+ return SECFailure; |
+ } |
+ |
+ buffer = (unsigned char *)PORT_Alloc(modulusLen); |
+ if (!buffer) { |
+ PORT_SetError(SEC_ERROR_NO_MEMORY); |
+ return SECFailure; |
+ } |
+ |
+ rv = RSA_PublicKeyOp(key, buffer, sig); |
+ if (rv != SECSuccess) { |
+ PORT_Free(buffer); |
+ PORT_SetError(SEC_ERROR_BAD_SIGNATURE); |
+ return SECFailure; |
+ } |
+ |
+ rv = emsa_pss_verify(hash, buffer, modulusLen, hashAlg, |
+ maskHashAlg, saltLength); |
+ PORT_Free(buffer); |
+ |
+ return rv; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_Sign(RSAPrivateKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * input, |
+ unsigned int inputLen) |
+{ |
+ SECStatus rv = SECSuccess; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ SECItem formatted; |
+ SECItem unformatted; |
+ |
+ if (maxOutputLen < modulusLen) |
+ return SECFailure; |
+ |
+ unformatted.len = inputLen; |
+ unformatted.data = (unsigned char*)input; |
+ formatted.data = NULL; |
+ rv = rsa_FormatBlock(&formatted, modulusLen, RSA_BlockPrivate, |
+ &unformatted); |
+ if (rv != SECSuccess) |
+ goto done; |
+ |
+ rv = RSA_PrivateKeyOpDoubleChecked(key, output, formatted.data); |
+ *outputLen = modulusLen; |
+ |
+ goto done; |
+ |
+done: |
+ if (formatted.data != NULL) |
+ PORT_ZFree(formatted.data, modulusLen); |
+ return rv; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_CheckSign(RSAPublicKey * key, |
+ const unsigned char * sig, |
+ unsigned int sigLen, |
+ const unsigned char * data, |
+ unsigned int dataLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned int i; |
+ unsigned char * buffer; |
+ |
+ if (sigLen != modulusLen) |
+ goto failure; |
+ /* |
+ * 0x00 || BT || Pad || 0x00 || ActualData |
+ * |
+ * The "3" below is the first octet + the second octet + the 0x00 |
+ * octet that always comes just before the ActualData. |
+ */ |
+ if (dataLen > modulusLen - (3 + RSA_BLOCK_MIN_PAD_LEN)) |
+ goto failure; |
+ |
+ buffer = (unsigned char *)PORT_Alloc(modulusLen + 1); |
+ if (!buffer) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, buffer, sig); |
+ if (rv != SECSuccess) |
+ goto loser; |
+ |
+ /* |
+ * check the padding that was used |
+ */ |
+ if (buffer[0] != RSA_BLOCK_FIRST_OCTET || |
+ buffer[1] != (unsigned char)RSA_BlockPrivate) { |
+ goto loser; |
+ } |
+ for (i = 2; i < modulusLen - dataLen - 1; i++) { |
+ if (buffer[i] != RSA_BLOCK_PRIVATE_PAD_OCTET) |
+ goto loser; |
+ } |
+ if (buffer[i] != RSA_BLOCK_AFTER_PAD_OCTET) |
+ goto loser; |
+ |
+ /* |
+ * make sure we get the same results |
+ */ |
+ if (PORT_Memcmp(buffer + modulusLen - dataLen, data, dataLen) != 0) |
+ goto loser; |
+ |
+ PORT_Free(buffer); |
+ return SECSuccess; |
+ |
+loser: |
+ PORT_Free(buffer); |
+failure: |
+ return SECFailure; |
+} |
+ |
+/* XXX Doesn't set error code */ |
+SECStatus |
+RSA_CheckSignRecover(RSAPublicKey * key, |
+ unsigned char * output, |
+ unsigned int * outputLen, |
+ unsigned int maxOutputLen, |
+ const unsigned char * sig, |
+ unsigned int sigLen) |
+{ |
+ SECStatus rv; |
+ unsigned int modulusLen = rsa_modulusLen(&key->modulus); |
+ unsigned int i; |
+ unsigned char * buffer; |
+ |
+ if (sigLen != modulusLen) |
+ goto failure; |
+ |
+ buffer = (unsigned char *)PORT_Alloc(modulusLen + 1); |
+ if (!buffer) |
+ goto failure; |
+ |
+ rv = RSA_PublicKeyOp(key, buffer, sig); |
+ if (rv != SECSuccess) |
+ goto loser; |
+ *outputLen = 0; |
+ |
+ /* |
+ * check the padding that was used |
+ */ |
+ if (buffer[0] != RSA_BLOCK_FIRST_OCTET || |
+ buffer[1] != (unsigned char)RSA_BlockPrivate) { |
+ goto loser; |
+ } |
+ for (i = 2; i < modulusLen; i++) { |
+ if (buffer[i] == RSA_BLOCK_AFTER_PAD_OCTET) { |
+ *outputLen = modulusLen - i - 1; |
+ break; |
+ } |
+ if (buffer[i] != RSA_BLOCK_PRIVATE_PAD_OCTET) |
+ goto loser; |
+ } |
+ if (*outputLen == 0) |
+ goto loser; |
+ if (*outputLen > maxOutputLen) |
+ goto loser; |
+ |
+ PORT_Memcpy(output, buffer + modulusLen - *outputLen, *outputLen); |
+ |
+ PORT_Free(buffer); |
+ return SECSuccess; |
+ |
+loser: |
+ PORT_Free(buffer); |
+failure: |
+ return SECFailure; |
+} |