- markus@cvs.openbsd.org 2001/04/30 15:50:46

     [compat.c compat.h kex.c]
     allow interop with weaker key generation used by ssh-2.0.x, x < 10

diff --git a/ChangeLog b/ChangeLog
index 86a953a26bcd39b8d890cdc92e49414ec6dfe4ee..6733f7d53d63847fbe40f5c145f0f0daf4cae5d2 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,9 @@
    - markus@cvs.openbsd.org 2001/04/30 11:18:52
      [readconf.c readconf.h ssh.1 ssh.c sshconnect.c]
      implement 'ssh -b bind_address' like 'telnet -b'
+   - markus@cvs.openbsd.org 2001/04/30 15:50:46
+     [compat.c compat.h kex.c]
+     allow interop with weaker key generation used by ssh-2.0.x, x < 10
  - (tim) [contrib/caldera/openssh.spec] add Requires line for Caldera 3.1
 
 20010430

diff --git a/compat.c b/compat.c
index 683da100f891ddc689d326696ee4a9b3b8c3a7bd..faf66fe427a0b4a473c9b60fad0e61c4cbb9f03f 100644 (file)
--- a/compat.c
+++ b/compat.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: compat.c,v 1.48 2001/04/29 19:16:52 markus Exp $");
+RCSID("$OpenBSD: compat.c,v 1.49 2001/04/30 15:50:46 markus Exp $");
 
 #ifdef HAVE_LIBPCRE
 #  include <pcreposix.h>
@@ -94,11 +94,17 @@ compat_datafellows(const char *version)
                                        SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
                                        SSH_BUG_PKOK|SSH_BUG_RSASIGMD5|
                                        SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE },
-               { "^2\\.0\\.",          SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+               { "^2\\.0\\.1[0-2]",    SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
                                        SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
                                        SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
                                        SSH_BUG_PKAUTH|SSH_BUG_PKOK|
                                        SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE },
+               { "^2\\.0\\.",          SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+                                       SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+                                       SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
+                                       SSH_BUG_PKAUTH|SSH_BUG_PKOK|
+                                       SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
+                                       SSH_BUG_DERIVEKEY },
                { "^2\\.[23]\\.0",      SSH_BUG_HMAC|SSH_BUG_RSASIGMD5 },
                { "^2\\.3\\.",          SSH_BUG_RSASIGMD5 },
                { "^2\\.[2-9]\\.",      0 },

diff --git a/compat.h b/compat.h
index fa509c247f40cfe81b588759e9a1de846734b387..0ccc1ed375f4a38c952245f8702256ba392b7892 100644 (file)
--- a/compat.h
+++ b/compat.h
@@ -21,7 +21,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-/* RCSID("$OpenBSD: compat.h,v 1.24 2001/04/29 19:16:52 markus Exp $"); */
+/* RCSID("$OpenBSD: compat.h,v 1.25 2001/04/30 15:50:46 markus Exp $"); */
 
 #ifndef COMPAT_H
 #define COMPAT_H
@@ -49,6 +49,7 @@
 #define SSH_BUG_NOREKEY                0x00008000
 #define SSH_BUG_HBSERVICE      0x00010000
 #define SSH_BUG_OPENFAILURE    0x00020000
+#define SSH_BUG_DERIVEKEY      0x00040000
 
 void    enable_compat13(void);
 void    enable_compat20(void);

diff --git a/kex.c b/kex.c
index 69ba102e169405c44ff088bfa31dee8a9d9b798c..6b68ba5046d83b38637cc51d3f8f9606b73fd508 100644 (file)
--- a/kex.c
+++ b/kex.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: kex.c,v 1.33 2001/04/05 10:42:50 markus Exp $");
+RCSID("$OpenBSD: kex.c,v 1.34 2001/04/30 15:50:46 markus Exp $");
 
 #include <openssl/crypto.h>
 
@@ -375,7 +375,8 @@ derive_key(Kex *kex, int id, int need, u_char *hash, BIGNUM *shared_secret)
 
        /* K1 = HASH(K || H || "A" || session_id) */
        EVP_DigestInit(&md, evp_md);
-       EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
+       if (!(datafellows & SSH_BUG_DERIVEKEY))
+               EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
        EVP_DigestUpdate(&md, hash, mdsz);
        EVP_DigestUpdate(&md, &c, 1);
        EVP_DigestUpdate(&md, kex->session_id, kex->session_id_len);
@@ -388,7 +389,8 @@ derive_key(Kex *kex, int id, int need, u_char *hash, BIGNUM *shared_secret)
         */
        for (have = mdsz; need > have; have += mdsz) {
                EVP_DigestInit(&md, evp_md);
-               EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
+               if (!(datafellows & SSH_BUG_DERIVEKEY))
+                       EVP_DigestUpdate(&md, buffer_ptr(&b), buffer_len(&b));
                EVP_DigestUpdate(&md, hash, mdsz);
                EVP_DigestUpdate(&md, digest, have);
                EVP_DigestFinal(&md, digest + have, NULL);