Import of OpenSSH 3.3p1

[gssapi-openssh.git] / openssh / ssh-rsa.c

diff --git a/openssh/ssh-rsa.c b/openssh/ssh-rsa.c
index 8e79d4e1d310749269e80341b258c0155de08610..3e66294e9f8c4ad939cfb0a8b40e8b5c673f5728 100644 (file)
--- a/openssh/ssh-rsa.c
+++ b/openssh/ssh-rsa.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-rsa.c,v 1.16 2002/02/24 19:14:59 markus Exp $");
+RCSID("$OpenBSD: ssh-rsa.c,v 1.20 2002/06/10 16:53:06 stevesk Exp $");
 
 #include <openssl/evp.h>
 #include <openssl/err.h>
@@ -35,6 +35,7 @@ RCSID("$OpenBSD: ssh-rsa.c,v 1.16 2002/02/24 19:14:59 markus Exp $");
 #include "key.h"
 #include "ssh-rsa.h"
 #include "compat.h"
+#include "ssh.h"
 
 /* RSASSA-PKCS1-v1_5 (PKCS #1 v2.0 signature) with SHA1 */
 int
@@ -54,10 +55,6 @@ ssh_rsa_sign(
                error("ssh_rsa_sign: no RSA key");
                return -1;
        }
-       if (datafellows & SSH_BUG_SIGBLOB) {
-               error("ssh_rsa_sign: SSH_BUG_SIGBLOB not supported");
-               return -1;
-       }
        nid = (datafellows & SSH_BUG_RSASIGMD5) ? NID_md5 : NID_sha1;
        if ((evp_md = EVP_get_digestbynid(nid)) == NULL) {
                error("ssh_rsa_sign: EVP_get_digestbynid %d failed", nid);
@@ -118,20 +115,16 @@ ssh_rsa_verify(
        EVP_MD_CTX md;
        char *ktype;
        u_char digest[EVP_MAX_MD_SIZE], *sigblob;
-       u_int len, dlen;
+       u_int len, dlen, modlen;
        int rlen, ret, nid;
 
        if (key == NULL || key->type != KEY_RSA || key->rsa == NULL) {
                error("ssh_rsa_verify: no RSA key");
                return -1;
        }
-       if (datafellows & SSH_BUG_SIGBLOB) {
-               error("ssh_rsa_verify: SSH_BUG_SIGBLOB not supported");
-               return -1;
-       }
-       if (BN_num_bits(key->rsa->n) < 768) {
-               error("ssh_rsa_verify: n too small: %d bits",
-                   BN_num_bits(key->rsa->n));
+       if (BN_num_bits(key->rsa->n) < SSH_RSA_MINIMUM_MODULUS_SIZE) {
+               error("ssh_rsa_verify: RSA modulus too small: %d < minimum %d bits",
+                   BN_num_bits(key->rsa->n), SSH_RSA_MINIMUM_MODULUS_SIZE);
                return -1;
        }
        buffer_init(&b);
@@ -152,6 +145,21 @@ ssh_rsa_verify(
                xfree(sigblob);
                return -1;
        }
+       /* RSA_verify expects a signature of RSA_size */
+       modlen = RSA_size(key->rsa);
+       if (len > modlen) {
+               error("ssh_rsa_verify: len %d > modlen %d", len, modlen);
+               xfree(sigblob);
+               return -1;
+       } else if (len < modlen) {
+               int diff = modlen - len;
+               debug("ssh_rsa_verify: add padding: modlen %d > len %d",
+                   modlen, len);
+               sigblob = xrealloc(sigblob, modlen);
+               memmove(sigblob + diff, sigblob, len);
+               memset(sigblob, 0, diff);
+               len = modlen;
+       }
        nid = (datafellows & SSH_BUG_RSASIGMD5) ? NID_md5 : NID_sha1;
        if ((evp_md = EVP_get_digestbynid(nid)) == NULL) {
                error("ssh_rsa_verify: EVP_get_digestbynid %d failed", nid);