-/* crypto/rsa/rsa_sign.c */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
- *
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to. The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code. The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * "This product includes cryptographic software written by
- * Eric Young (eay@cryptsoft.com)"
- * The word 'cryptographic' can be left out if the rouines from the library
- * being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- * the apps directory (application code) you must include an acknowledgement:
- * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
+/*
+ * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
*
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed. i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
+ * Licensed under the OpenSSL license (the "License"). You may not use
+ * this file except in compliance with the License. You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
*/
#include <stdio.h>
-#include "cryptlib.h"
+#include "internal/cryptlib.h"
#include <openssl/bn.h>
#include <openssl/rsa.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
+#include "internal/x509_int.h"
#include "rsa_locl.h"
/* Size of an SSL signature: MD5+SHA1 */
#define SSL_SIG_LENGTH 36
-int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
- unsigned char *sigret, unsigned int *siglen, RSA *rsa)
+/*
+ * encode_pkcs1 encodes a DigestInfo prefix of hash |type| and digest |m|, as
+ * described in EMSA-PKCS1-v1_5-ENCODE, RFC 3447 section 9.2 step 2. This
+ * encodes the DigestInfo (T and tLen) but does not add the padding.
+ *
+ * On success, it returns one and sets |*out| to a newly allocated buffer
+ * containing the result and |*out_len| to its length. The caller must free
+ * |*out| with |OPENSSL_free|. Otherwise, it returns zero.
+ */
+static int encode_pkcs1(unsigned char **out, int *out_len, int type,
+ const unsigned char *m, unsigned int m_len)
{
X509_SIG sig;
- ASN1_TYPE parameter;
- int i, j, ret = 1;
- unsigned char *p, *tmps = NULL;
- const unsigned char *s = NULL;
X509_ALGOR algor;
+ ASN1_TYPE parameter;
ASN1_OCTET_STRING digest;
- if ((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign) {
+ uint8_t *der = NULL;
+ int len;
+
+ sig.algor = &algor;
+ sig.algor->algorithm = OBJ_nid2obj(type);
+ if (sig.algor->algorithm == NULL) {
+ RSAerr(RSA_F_ENCODE_PKCS1, RSA_R_UNKNOWN_ALGORITHM_TYPE);
+ return 0;
+ }
+ if (OBJ_length(sig.algor->algorithm) == 0) {
+ RSAerr(RSA_F_ENCODE_PKCS1,
+ RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
+ return 0;
+ }
+ parameter.type = V_ASN1_NULL;
+ parameter.value.ptr = NULL;
+ sig.algor->parameter = ¶meter;
+
+ sig.digest = &digest;
+ sig.digest->data = (unsigned char *)m;
+ sig.digest->length = m_len;
+
+ len = i2d_X509_SIG(&sig, &der);
+ if (len < 0)
+ return 0;
+
+ *out = der;
+ *out_len = len;
+ return 1;
+}
+
+int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
+ unsigned char *sigret, unsigned int *siglen, RSA *rsa)
+{
+ int encrypt_len, encoded_len = 0, ret = 0;
+ unsigned char *tmps = NULL;
+ const unsigned char *encoded = NULL;
+
+ if (rsa->meth->rsa_sign) {
return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
}
- /* Special case: SSL signature, just check the length */
+
+ /* Compute the encoded digest. */
if (type == NID_md5_sha1) {
+ /*
+ * NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
+ * earlier. It has no DigestInfo wrapper but otherwise is
+ * RSASSA-PKCS1-v1_5.
+ */
if (m_len != SSL_SIG_LENGTH) {
RSAerr(RSA_F_RSA_SIGN, RSA_R_INVALID_MESSAGE_LENGTH);
- return (0);
+ return 0;
}
- i = SSL_SIG_LENGTH;
- s = m;
+ encoded_len = SSL_SIG_LENGTH;
+ encoded = m;
} else {
- sig.algor = &algor;
- sig.algor->algorithm = OBJ_nid2obj(type);
- if (sig.algor->algorithm == NULL) {
- RSAerr(RSA_F_RSA_SIGN, RSA_R_UNKNOWN_ALGORITHM_TYPE);
- return (0);
- }
- if (OBJ_length(sig.algor->algorithm) == 0) {
- RSAerr(RSA_F_RSA_SIGN,
- RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
- return (0);
- }
- parameter.type = V_ASN1_NULL;
- parameter.value.ptr = NULL;
- sig.algor->parameter = ¶meter;
-
- sig.digest = &digest;
- sig.digest->data = (unsigned char *)m; /* TMP UGLY CAST */
- sig.digest->length = m_len;
-
- i = i2d_X509_SIG(&sig, NULL);
+ if (!encode_pkcs1(&tmps, &encoded_len, type, m, m_len))
+ goto err;
+ encoded = tmps;
}
- j = RSA_size(rsa);
- if (i > (j - RSA_PKCS1_PADDING_SIZE)) {
+
+ if (encoded_len > RSA_size(rsa) - RSA_PKCS1_PADDING_SIZE) {
RSAerr(RSA_F_RSA_SIGN, RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
- return (0);
- }
- if (type != NID_md5_sha1) {
- tmps = (unsigned char *)OPENSSL_malloc((unsigned int)j + 1);
- if (tmps == NULL) {
- RSAerr(RSA_F_RSA_SIGN, ERR_R_MALLOC_FAILURE);
- return (0);
- }
- p = tmps;
- i2d_X509_SIG(&sig, &p);
- s = tmps;
+ goto err;
}
- i = RSA_private_encrypt(i, s, sigret, rsa, RSA_PKCS1_PADDING);
- if (i <= 0)
- ret = 0;
- else
- *siglen = i;
+ encrypt_len = RSA_private_encrypt(encoded_len, encoded, sigret, rsa,
+ RSA_PKCS1_PADDING);
+ if (encrypt_len <= 0)
+ goto err;
- if (type != NID_md5_sha1) {
- OPENSSL_cleanse(tmps, (unsigned int)j + 1);
- OPENSSL_free(tmps);
- }
- return (ret);
-}
+ *siglen = encrypt_len;
+ ret = 1;
-/*
- * Check DigestInfo structure does not contain extraneous data by reencoding
- * using DER and checking encoding against original.
- */
-static int rsa_check_digestinfo(X509_SIG *sig, const unsigned char *dinfo,
- int dinfolen)
-{
- unsigned char *der = NULL;
- int derlen;
- int ret = 0;
- derlen = i2d_X509_SIG(sig, &der);
- if (derlen <= 0)
- return 0;
- if (derlen == dinfolen && !memcmp(dinfo, der, derlen))
- ret = 1;
- OPENSSL_cleanse(der, derlen);
- OPENSSL_free(der);
+err:
+ OPENSSL_clear_free(tmps, (size_t)encoded_len);
return ret;
}
-int int_rsa_verify(int dtype, const unsigned char *m,
- unsigned int m_len,
+/*
+ * int_rsa_verify verifies an RSA signature in |sigbuf| using |rsa|. It may be
+ * called in two modes. If |rm| is NULL, it verifies the signature for digest
+ * |m|. Otherwise, it recovers the digest from the signature, writing the digest
+ * to |rm| and the length to |*prm_len|. |type| is the NID of the digest
+ * algorithm to use. It returns one on successful verification and zero
+ * otherwise.
+ */
+int int_rsa_verify(int type, const unsigned char *m, unsigned int m_len,
unsigned char *rm, size_t *prm_len,
const unsigned char *sigbuf, size_t siglen, RSA *rsa)
{
- int i, ret = 0, sigtype;
- unsigned char *s;
- X509_SIG *sig = NULL;
+ int decrypt_len, ret = 0, encoded_len = 0;
+ unsigned char *decrypt_buf = NULL, *encoded = NULL;
- if (siglen != (unsigned int)RSA_size(rsa)) {
+ if (siglen != (size_t)RSA_size(rsa)) {
RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_WRONG_SIGNATURE_LENGTH);
- return (0);
- }
-
- if ((dtype == NID_md5_sha1) && rm) {
- i = RSA_public_decrypt((int)siglen,
- sigbuf, rm, rsa, RSA_PKCS1_PADDING);
- if (i <= 0)
- return 0;
- *prm_len = i;
- return 1;
+ return 0;
}
- s = (unsigned char *)OPENSSL_malloc((unsigned int)siglen);
- if (s == NULL) {
+ /* Recover the encoded digest. */
+ decrypt_buf = OPENSSL_malloc(siglen);
+ if (decrypt_buf == NULL) {
RSAerr(RSA_F_INT_RSA_VERIFY, ERR_R_MALLOC_FAILURE);
goto err;
}
- if ((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH)) {
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_MESSAGE_LENGTH);
- goto err;
- }
- i = RSA_public_decrypt((int)siglen, sigbuf, s, rsa, RSA_PKCS1_PADDING);
- if (i <= 0)
+ decrypt_len = RSA_public_decrypt((int)siglen, sigbuf, decrypt_buf, rsa,
+ RSA_PKCS1_PADDING);
+ if (decrypt_len <= 0)
goto err;
- /*
- * Oddball MDC2 case: signature can be OCTET STRING. check for correct
- * tag and length octets.
- */
- if (dtype == NID_mdc2 && i == 18 && s[0] == 0x04 && s[1] == 0x10) {
- if (rm) {
- memcpy(rm, s + 2, 16);
- *prm_len = 16;
- ret = 1;
- } else if (memcmp(m, s + 2, 16))
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
- else
- ret = 1;
- }
- /* Special case: SSL signature */
- if (dtype == NID_md5_sha1) {
- if ((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
+ if (type == NID_md5_sha1) {
+ /*
+ * NID_md5_sha1 corresponds to the MD5/SHA1 combination in TLS 1.1 and
+ * earlier. It has no DigestInfo wrapper but otherwise is
+ * RSASSA-PKCS1-v1_5.
+ */
+ if (decrypt_len != SSL_SIG_LENGTH) {
RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
- else
- ret = 1;
- } else {
- const unsigned char *p = s;
- sig = d2i_X509_SIG(NULL, &p, (long)i);
-
- if (sig == NULL)
goto err;
+ }
- /* Excess data can be used to create forgeries */
- if (p != s + i || !rsa_check_digestinfo(sig, s, i)) {
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
- goto err;
+ if (rm != NULL) {
+ memcpy(rm, decrypt_buf, SSL_SIG_LENGTH);
+ *prm_len = SSL_SIG_LENGTH;
+ } else {
+ if (m_len != SSL_SIG_LENGTH) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_MESSAGE_LENGTH);
+ goto err;
+ }
+
+ if (memcmp(decrypt_buf, m, SSL_SIG_LENGTH) != 0) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
+ goto err;
+ }
}
+ } else if (type == NID_mdc2 && decrypt_len == 2 + 16
+ && decrypt_buf[0] == 0x04 && decrypt_buf[1] == 0x10) {
+ /*
+ * Oddball MDC2 case: signature can be OCTET STRING. check for correct
+ * tag and length octets.
+ */
+ if (rm != NULL) {
+ memcpy(rm, decrypt_buf + 2, 16);
+ *prm_len = 16;
+ } else {
+ if (m_len != 16) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_MESSAGE_LENGTH);
+ goto err;
+ }
+ if (memcmp(m, decrypt_buf + 2, 16) != 0) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
+ goto err;
+ }
+ }
+ } else {
/*
- * Parameters to the signature algorithm can also be used to create
- * forgeries
+ * If recovering the digest, extract a digest-sized output from the end
+ * of |decrypt_buf| for |encode_pkcs1|, then compare the decryption
+ * output as in a standard verification.
*/
- if (sig->algor->parameter
- && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) {
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
- goto err;
+ if (rm != NULL) {
+ const EVP_MD *md = EVP_get_digestbynid(type);
+ if (md == NULL) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_UNKNOWN_ALGORITHM_TYPE);
+ goto err;
+ }
+
+ m_len = EVP_MD_size(md);
+ if (m_len > (size_t)decrypt_len) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_DIGEST_LENGTH);
+ goto err;
+ }
+ m = decrypt_buf + decrypt_len - m_len;
}
- sigtype = OBJ_obj2nid(sig->algor->algorithm);
+ /* Construct the encoded digest and ensure it matches. */
+ if (!encode_pkcs1(&encoded, &encoded_len, type, m, m_len))
+ goto err;
-#ifdef RSA_DEBUG
- /* put a backward compatibility flag in EAY */
- fprintf(stderr, "in(%s) expect(%s)\n", OBJ_nid2ln(sigtype),
- OBJ_nid2ln(dtype));
-#endif
- if (sigtype != dtype) {
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_ALGORITHM_MISMATCH);
+ if (encoded_len != decrypt_len
+ || memcmp(encoded, decrypt_buf, encoded_len) != 0) {
+ RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
goto err;
}
- if (rm) {
- const EVP_MD *md;
- md = EVP_get_digestbynid(dtype);
- if (md && (EVP_MD_size(md) != sig->digest->length))
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_DIGEST_LENGTH);
- else {
- memcpy(rm, sig->digest->data, sig->digest->length);
- *prm_len = sig->digest->length;
- ret = 1;
- }
- } else if (((unsigned int)sig->digest->length != m_len) ||
- (memcmp(m, sig->digest->data, m_len) != 0)) {
- RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
- } else
- ret = 1;
- }
- err:
- if (sig != NULL)
- X509_SIG_free(sig);
- if (s != NULL) {
- OPENSSL_cleanse(s, (unsigned int)siglen);
- OPENSSL_free(s);
+
+ /* Output the recovered digest. */
+ if (rm != NULL) {
+ memcpy(rm, m, m_len);
+ *prm_len = m_len;
+ }
}
- return (ret);
+
+ ret = 1;
+
+err:
+ OPENSSL_clear_free(encoded, (size_t)encoded_len);
+ OPENSSL_clear_free(decrypt_buf, siglen);
+ return ret;
}
-int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
+int RSA_verify(int type, const unsigned char *m, unsigned int m_len,
const unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
{
- if ((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify) {
- return rsa->meth->rsa_verify(dtype, m, m_len, sigbuf, siglen, rsa);
+ if (rsa->meth->rsa_verify) {
+ return rsa->meth->rsa_verify(type, m, m_len, sigbuf, siglen, rsa);
}
- return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
+ return int_rsa_verify(type, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
}
projects / openssl.git / blobdiff