- markus@cvs.openbsd.org 2002/06/08 05:07:56

[openssh.git] / ssh-rsa.c

diff --git a/ssh-rsa.c b/ssh-rsa.c
index c4339b95bd12d3c5cc66436203afbfbc921cfcdf..458c9c840efab6d4375b655de7ce18d2a3090059 100644 (file)
--- a/ssh-rsa.c
+++ b/ssh-rsa.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh-rsa.c,v 1.15 2002/01/25 21:42:11 markus Exp $");
+RCSID("$OpenBSD: ssh-rsa.c,v 1.19 2002/05/31 13:20:50 markus Exp $");
 
 #include <openssl/evp.h>
 #include <openssl/err.h>
@@ -35,13 +35,14 @@ RCSID("$OpenBSD: ssh-rsa.c,v 1.15 2002/01/25 21:42:11 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
 ssh_rsa_sign(
     Key *key,
-    u_char **sigp, int *lenp,
-    u_char *data, int datalen)
+    u_char **sigp, u_int *lenp,
+    u_char *data, u_int datalen)
 {
        const EVP_MD *evp_md;
        EVP_MD_CTX md;
@@ -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);
@@ -110,26 +107,22 @@ ssh_rsa_sign(
 int
 ssh_rsa_verify(
     Key *key,
-    u_char *signature, int signaturelen,
-    u_char *data, int datalen)
+    u_char *signature, u_int signaturelen,
+    u_char *data, u_int datalen)
 {
        Buffer b;
        const EVP_MD *evp_md;
        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) {
+       if (BN_num_bits(key->rsa->n) < SSH_RSA_MINIMUM_MODULUS_SIZE) {
                error("ssh_rsa_verify: n too small: %d bits",
                    BN_num_bits(key->rsa->n));
                return -1;
@@ -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);