RepoMirrors
/
openssh
mirror of git://anongit.mindrot.org/openssh.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

- markus@cvs.openbsd.org 2002/08/02 22:20:30 

[ssh-rsa.c]
     replace RSA_verify with our own version and avoid the OpenSSL ASN.1 parser
     for authentication; ok deraadt/djm
This commit is contained in:
Ben Lindstrom 2002-08-20 18:40:03 +00:00
parent 0e50d846b3
commit 0deb5d958a
2 changed files with 98 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
ChangeLog
View File

@ -13,6 +13,10 @@
- markus@cvs.openbsd.org 2002/08/02 21:23:41
[ssh-rsa.c]
diff is u_int (2x); ok deraadt/provos
- markus@cvs.openbsd.org 2002/08/02 22:20:30
[ssh-rsa.c]
replace RSA_verify with our own version and avoid the OpenSSL ASN.1 parser
for authentication; ok deraadt/djm
20020813
- (tim) [configure.ac] Display OpenSSL header/library version.
@ -1510,4 +1514,4 @@
- (stevesk) entropy.c: typo in debug message
- (djm) ssh-keygen -i needs seeded RNG; report from markus@
$Id: ChangeLog,v 1.2417 2002/08/20 18:39:14 mouring Exp $
$Id: ChangeLog,v 1.2418 2002/08/20 18:40:03 mouring Exp $

100
ssh-rsa.c
View File

@ -23,7 +23,7 @@
*/
#include "includes.h"
RCSID("$OpenBSD: ssh-rsa.c,v 1.24 2002/08/02 21:23:41 markus Exp $");
RCSID("$OpenBSD: ssh-rsa.c,v 1.25 2002/08/02 22:20:30 markus Exp $");
#include <openssl/evp.h>
#include <openssl/err.h>
@ -37,6 +37,8 @@ RCSID("$OpenBSD: ssh-rsa.c,v 1.24 2002/08/02 21:23:41 markus Exp $");
#include "compat.h"
#include "ssh.h"
static int openssh_RSA_verify(int, u_char *, u_int, u_char *, u_int , RSA *);
/* RSASSA-PKCS1-v1_5 (PKCS #1 v2.0 signature) with SHA1 */
int
ssh_rsa_sign(Key *key, u_char **sigp, u_int *lenp,
@ -167,15 +169,99 @@ ssh_rsa_verify(Key *key, u_char *signature, u_int signaturelen,
EVP_DigestUpdate(&md, data, datalen);
EVP_DigestFinal(&md, digest, &dlen);
ret = RSA_verify(nid, digest, dlen, sigblob, len, key->rsa);
ret = openssh_RSA_verify(nid, digest, dlen, sigblob, len, key->rsa);
memset(digest, 'd', sizeof(digest));
memset(sigblob, 's', len);
xfree(sigblob);
if (ret == 0) {
int ecode = ERR_get_error();
error("ssh_rsa_verify: RSA_verify failed: %s",
ERR_error_string(ecode, NULL));
}
debug("ssh_rsa_verify: signature %scorrect", (ret==0) ? "in" : "");
return ret;
}
/*
* See:
* http://www.rsasecurity.com/rsalabs/pkcs/pkcs-1/
* ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1.asn
*/
/*
* id-sha1 OBJECT IDENTIFIER ::= { iso(1) identified-organization(3)
* oiw(14) secsig(3) algorithms(2) 26 }
*/
static const u_char id_sha1[] = {
0x30, 0x21, /* type Sequence, length 0x21 (33) */
0x30, 0x09, /* type Sequence, length 0x09 */
0x06, 0x05, /* type OID, length 0x05 */
0x2b, 0x0e, 0x03, 0x02, 0x1a, /* id-sha1 OID */
0x05, 0x00, /* NULL */
0x04, 0x14 /* Octet string, length 0x14 (20), followed by sha1 hash */
};
/*
* id-md5 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
* rsadsi(113549) digestAlgorithm(2) 5 }
*/
static const u_char id_md5[] = {
0x30, 0x20, /* type Sequence, length 0x20 (32) */
0x30, 0x0c, /* type Sequence, length 0x09 */
0x06, 0x08, /* type OID, length 0x05 */
0x2a, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x02, 0x05, /* id-md5 */
0x05, 0x00, /* NULL */
0x04, 0x10 /* Octet string, length 0x10 (16), followed by md5 hash */
};
static int
openssh_RSA_verify(int type, u_char *hash, u_int hashlen,
u_char *sigbuf, u_int siglen, RSA *rsa)
{
u_int ret, rsasize, len, oidlen = 0, hlen = 0;
const u_char *oid = NULL;
u_char *decrypted = NULL;
ret = 0;
switch (type) {
case NID_sha1:
oid = id_sha1;
oidlen = sizeof(id_sha1);
hlen = 20;
break;
case NID_md5:
oid = id_md5;
oidlen = sizeof(id_md5);
hlen = 16;
break;
default:
goto done;
break;
}
if (hashlen != hlen) {
error("bad hashlen");
goto done;
}
rsasize = RSA_size(rsa);
if (siglen == 0 || siglen > rsasize) {
error("bad siglen");
goto done;
}
decrypted = xmalloc(rsasize);
if ((len = RSA_public_decrypt(siglen, sigbuf, decrypted, rsa,
RSA_PKCS1_PADDING)) < 0) {
error("RSA_public_decrypt failed: %s",
ERR_error_string(ERR_get_error(), NULL));
goto done;
}
if (len != hlen + oidlen) {
error("bad decrypted len: %d != %d + %d", len, hlen, oidlen);
goto done;
}
if (memcmp(decrypted, oid, oidlen) != 0) {
error("oid mismatch");
goto done;
}
if (memcmp(decrypted + oidlen, hash, hlen) != 0) {
error("hash mismatch");
goto done;
}
ret = 1;
done:
if (decrypted)
xfree(decrypted);
return ret;
}