Disable buggy code variant in BN_mod_mul_montgomery that was enabled

in 0.9.6-beta1 and 0.9.6-beta2 and caused the BN_mont_exp_mont_word()
failure (bug report "openssh 2.2.0p1 fails with openssl 0.9.6-beta1").

diff --git a/crypto/bn/bn_mont.c b/crypto/bn/bn_mont.c
index ca58ad33d23eaa7138542d3634e111b3ff67966d..932f5cecef5a5052c6c105d8fc9705d173301318 100644 (file)
--- a/crypto/bn/bn_mont.c
+++ b/crypto/bn/bn_mont.c
@@ -85,7 +85,26 @@ int BN_mod_mul_montgomery(BIGNUM *r, BIGNUM *a, BIGNUM *b,
 
        if (a == b)
                {
-#if 1 
+#if 0 /* buggy -- try squaring  g  in the following parameters
+         (but note that squaring 2 or 4 works):
+Diffie-Hellman-Parameters: (1024 bit)
+    prime:
+        00:ff:ff:ff:ff:ff:ff:ff:ff:c9:0f:da:a2:21:68:
+        c2:34:c4:c6:62:8b:80:dc:1c:d1:29:02:4e:08:8a:
+        67:cc:74:02:0b:be:a6:3b:13:9b:22:51:4a:08:79:
+        8e:34:04:dd:ef:95:19:b3:cd:3a:43:1b:30:2b:0a:
+        6d:f2:5f:14:37:4f:e1:35:6d:6d:51:c2:45:e4:85:
+        b5:76:62:5e:7e:c6:f4:4c:42:e9:a6:37:ed:6b:0b:
+        ff:5c:b6:f4:06:b7:ed:ee:38:6b:fb:5a:89:9f:a5:
+        ae:9f:24:11:7c:4b:1f:e6:49:28:66:51:ec:e6:53:
+        81:ff:ff:ff:ff:ff:ff:ff:ff
+    generator: 8 (0x8)
+-----BEGIN DH PARAMETERS-----
+MIGHAoGBAP//////////yQ/aoiFowjTExmKLgNwc0SkCTgiKZ8x0Agu+pjsTmyJR
+Sgh5jjQE3e+VGbPNOkMbMCsKbfJfFDdP4TVtbVHCReSFtXZiXn7G9ExC6aY37WsL
+/1y29Aa37e44a/taiZ+lrp8kEXxLH+ZJKGZR7OZTgf//////////AgEI
+-----END DH PARAMETERS-----
+*/
                bn_wexpand(tmp,a->top*2);
                bn_wexpand(tmp2,a->top*4);
                bn_sqr_recursive(tmp->d,a->d,a->top,tmp2->d);