Oops.. =) mispelt NGROUPS_MAX.

[openssh.git] / sshd.c

diff --git a/sshd.c b/sshd.c
index d46e4aa8b051de98e06c430653b7fa997dded4f0..02fe2ec426885165c1b0eae6e51e637def373214 100644 (file)
--- a/sshd.c
+++ b/sshd.c
@@ -40,7 +40,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.158 2001/01/28 10:37:26 markus Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.159 2001/01/29 19:47:31 markus Exp $");
 
 #include <openssl/dh.h>
 #include <openssl/bn.h>
@@ -1186,6 +1186,7 @@ do_ssh1_kex(void)
 {
        int i, len;
        int plen, slen;
+       int rsafail = 0;
        BIGNUM *session_key_int;
        u_char session_key[SSH_SESSION_KEY_LENGTH];
        u_char cookie[8];
@@ -1296,7 +1297,7 @@ do_ssh1_kex(void)
         * with larger modulus first).
         */
        if (BN_cmp(sensitive_data.server_key->rsa->n, sensitive_data.ssh1_host_key->rsa->n) > 0) {
-               /* Private key has bigger modulus. */
+               /* Server key has bigger modulus. */
                if (BN_num_bits(sensitive_data.server_key->rsa->n) <
                    BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED) {
                        fatal("do_connection: %s: server_key %d < host_key %d + SSH_KEY_BITS_RESERVED %d",
@@ -1305,10 +1306,12 @@ do_ssh1_kex(void)
                            BN_num_bits(sensitive_data.ssh1_host_key->rsa->n),
                            SSH_KEY_BITS_RESERVED);
                }
-               rsa_private_decrypt(session_key_int, session_key_int,
-                   sensitive_data.server_key->rsa);
-               rsa_private_decrypt(session_key_int, session_key_int,
-                   sensitive_data.ssh1_host_key->rsa);
+               if (rsa_private_decrypt(session_key_int, session_key_int,
+                   sensitive_data.server_key->rsa) <= 0)
+                       rsafail++;
+               if (rsa_private_decrypt(session_key_int, session_key_int,
+                   sensitive_data.ssh1_host_key->rsa) <= 0)
+                       rsafail++;
        } else {
                /* Host key has bigger modulus (or they are equal). */
                if (BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) <
@@ -1319,10 +1322,12 @@ do_ssh1_kex(void)
                            BN_num_bits(sensitive_data.server_key->rsa->n),
                            SSH_KEY_BITS_RESERVED);
                }
-               rsa_private_decrypt(session_key_int, session_key_int,
-                   sensitive_data.ssh1_host_key->rsa);
-               rsa_private_decrypt(session_key_int, session_key_int,
-                   sensitive_data.server_key->rsa);
+               if (rsa_private_decrypt(session_key_int, session_key_int,
+                   sensitive_data.ssh1_host_key->rsa) < 0)
+                       rsafail++;
+               if (rsa_private_decrypt(session_key_int, session_key_int,
+                   sensitive_data.server_key->rsa) < 0)
+                       rsafail++;
        }
 
        compute_session_id(session_id, cookie,
@@ -1337,15 +1342,29 @@ do_ssh1_kex(void)
         * least significant 256 bits of the integer; the first byte of the
         * key is in the highest bits.
         */
-       BN_mask_bits(session_key_int, sizeof(session_key) * 8);
-       len = BN_num_bytes(session_key_int);
-       if (len < 0 || len > sizeof(session_key))
-               fatal("do_connection: bad len from %s: session_key_int %d > sizeof(session_key) %d",
-                   get_remote_ipaddr(),
-                   len, sizeof(session_key));
-       memset(session_key, 0, sizeof(session_key));
-       BN_bn2bin(session_key_int, session_key + sizeof(session_key) - len);
-
+       if (!rsafail) {
+               BN_mask_bits(session_key_int, sizeof(session_key) * 8);
+               len = BN_num_bytes(session_key_int);
+               if (len < 0 || len > sizeof(session_key)) {
+                       error("do_connection: bad session key len from %s: "
+                           "session_key_int %d > sizeof(session_key) %d",
+                           get_remote_ipaddr(), len, sizeof(session_key));
+                       rsafail++;
+               } else {
+                       memset(session_key, 0, sizeof(session_key));
+                       BN_bn2bin(session_key_int,
+                           session_key + sizeof(session_key) - len);
+               }
+       }
+       if (rsafail) {
+               log("do_connection: generating a fake encryption key");
+               for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
+                       if (i % 4 == 0)
+                               rand = arc4random();
+                       session_key[i] = rand & 0xff;
+                       rand >>= 8;
+               }
+       }
        /* Destroy the decrypted integer.  It is no longer needed. */
        BN_clear_free(session_key_int);