1 /* $OpenBSD: rsa_sign.c,v 1.26 2017/01/29 17:49:23 beck Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
62 #include <openssl/bn.h>
63 #include <openssl/err.h>
64 #include <openssl/objects.h>
65 #include <openssl/rsa.h>
66 #include <openssl/x509.h>
70 /* Size of an SSL signature: MD5+SHA1 */
71 #define SSL_SIG_LENGTH 36
74 RSA_sign(int type
, const unsigned char *m
, unsigned int m_len
,
75 unsigned char *sigret
, unsigned int *siglen
, RSA
*rsa
)
80 unsigned char *p
, *tmps
= NULL
;
81 const unsigned char *s
= NULL
;
83 ASN1_OCTET_STRING digest
;
85 if ((rsa
->flags
& RSA_FLAG_SIGN_VER
) && rsa
->meth
->rsa_sign
)
86 return rsa
->meth
->rsa_sign(type
, m
, m_len
, sigret
, siglen
, rsa
);
88 /* Special case: SSL signature, just check the length */
89 if (type
== NID_md5_sha1
) {
90 if (m_len
!= SSL_SIG_LENGTH
) {
91 RSAerror(RSA_R_INVALID_MESSAGE_LENGTH
);
98 sig
.algor
->algorithm
= OBJ_nid2obj(type
);
99 if (sig
.algor
->algorithm
== NULL
) {
100 RSAerror(RSA_R_UNKNOWN_ALGORITHM_TYPE
);
103 if (sig
.algor
->algorithm
->length
== 0) {
104 RSAerror(RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD
);
107 parameter
.type
= V_ASN1_NULL
;
108 parameter
.value
.ptr
= NULL
;
109 sig
.algor
->parameter
= ¶meter
;
111 sig
.digest
= &digest
;
112 sig
.digest
->data
= (unsigned char *)m
; /* TMP UGLY CAST */
113 sig
.digest
->length
= m_len
;
115 i
= i2d_X509_SIG(&sig
, NULL
);
118 if (i
> j
- RSA_PKCS1_PADDING_SIZE
) {
119 RSAerror(RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY
);
122 if (type
!= NID_md5_sha1
) {
123 tmps
= malloc(j
+ 1);
125 RSAerror(ERR_R_MALLOC_FAILURE
);
129 i2d_X509_SIG(&sig
, &p
);
132 i
= RSA_private_encrypt(i
, s
, sigret
, rsa
, RSA_PKCS1_PADDING
);
138 if (type
!= NID_md5_sha1
) {
139 explicit_bzero(tmps
, (unsigned int)j
+ 1);
146 int_rsa_verify(int dtype
, const unsigned char *m
, unsigned int m_len
,
147 unsigned char *rm
, size_t *prm_len
, const unsigned char *sigbuf
,
148 size_t siglen
, RSA
*rsa
)
150 int i
, ret
= 0, sigtype
;
152 X509_SIG
*sig
= NULL
;
154 if (siglen
!= (unsigned int)RSA_size(rsa
)) {
155 RSAerror(RSA_R_WRONG_SIGNATURE_LENGTH
);
159 if ((dtype
== NID_md5_sha1
) && rm
) {
160 i
= RSA_public_decrypt((int)siglen
, sigbuf
, rm
, rsa
,
170 RSAerror(ERR_R_MALLOC_FAILURE
);
173 if (dtype
== NID_md5_sha1
&& m_len
!= SSL_SIG_LENGTH
) {
174 RSAerror(RSA_R_INVALID_MESSAGE_LENGTH
);
177 i
= RSA_public_decrypt((int)siglen
, sigbuf
, s
, rsa
, RSA_PKCS1_PADDING
);
182 /* Special case: SSL signature */
183 if (dtype
== NID_md5_sha1
) {
184 if (i
!= SSL_SIG_LENGTH
|| memcmp(s
, m
, SSL_SIG_LENGTH
))
185 RSAerror(RSA_R_BAD_SIGNATURE
);
189 const unsigned char *p
= s
;
191 sig
= d2i_X509_SIG(NULL
, &p
, (long)i
);
196 /* Excess data can be used to create forgeries */
198 RSAerror(RSA_R_BAD_SIGNATURE
);
202 /* Parameters to the signature algorithm can also be used to
204 if (sig
->algor
->parameter
&&
205 ASN1_TYPE_get(sig
->algor
->parameter
) != V_ASN1_NULL
) {
206 RSAerror(RSA_R_BAD_SIGNATURE
);
210 sigtype
= OBJ_obj2nid(sig
->algor
->algorithm
);
212 if (sigtype
!= dtype
) {
213 RSAerror(RSA_R_ALGORITHM_MISMATCH
);
219 md
= EVP_get_digestbynid(dtype
);
220 if (md
&& (EVP_MD_size(md
) != sig
->digest
->length
))
221 RSAerror(RSA_R_INVALID_DIGEST_LENGTH
);
223 memcpy(rm
, sig
->digest
->data
,
224 sig
->digest
->length
);
225 *prm_len
= sig
->digest
->length
;
228 } else if ((unsigned int)sig
->digest
->length
!= m_len
||
229 memcmp(m
, sig
->digest
->data
, m_len
) != 0) {
230 RSAerror(RSA_R_BAD_SIGNATURE
);
238 explicit_bzero(s
, (unsigned int)siglen
);
245 RSA_verify(int dtype
, const unsigned char *m
, unsigned int m_len
,
246 const unsigned char *sigbuf
, unsigned int siglen
, RSA
*rsa
)
248 if ((rsa
->flags
& RSA_FLAG_SIGN_VER
) && rsa
->meth
->rsa_verify
)
249 return rsa
->meth
->rsa_verify(dtype
, m
, m_len
, sigbuf
, siglen
,
252 return int_rsa_verify(dtype
, m
, m_len
, NULL
, NULL
, sigbuf
, siglen
, rsa
);