3 files changed, 54 insertions, 40 deletions

diff --git a/src/lib/libssl/s23_clnt.c b/src/lib/libssl/s23_clnt.c
index 8674cdf627..2511a94b28 100644
--- a/src/lib/libssl/s23_clnt.c
+++ b/src/lib/libssl/s23_clnt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s23_clnt.c,v 1.47 2016/12/04 14:32:30 jsing Exp $ */
+/* $OpenBSD: s23_clnt.c,v 1.48 2016/12/30 16:57:01 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -231,43 +231,15 @@ ssl23_client_hello(SSL *s)
         unsigned char *buf;
         unsigned char *p, *d;
         unsigned long l;
-        int version = 0, version_major, version_minor;
-        int ret;
-        unsigned long mask, options = s->options;
+        uint16_t version;
         size_t outlen;
-
-        /*
-         * SSL_OP_NO_X disables all protocols above X *if* there are
-         * some protocols below X enabled. This is required in order
-         * to maintain "version capability" vector contiguous. So
-         * that if application wants to disable TLS1.0 in favour of
-         * TLS1>=1, it would be insufficient to pass SSL_NO_TLSv1, the
-         * answer is SSL_OP_NO_TLSv1|SSL_OP_NO_SSLv3|SSL_OP_NO_SSLv2.
-         */
-        mask = SSL_OP_NO_TLSv1_1|SSL_OP_NO_TLSv1;
-        version = TLS1_2_VERSION;
-
-        if ((options & SSL_OP_NO_TLSv1_2) && (options & mask) != mask)
-                version = TLS1_1_VERSION;
-        mask &= ~SSL_OP_NO_TLSv1_1;
-        if ((options & SSL_OP_NO_TLSv1_1) && (options & mask) != mask)
-                version = TLS1_VERSION;
-        mask &= ~SSL_OP_NO_TLSv1;
+        int ret;
 
         buf = (unsigned char *)s->init_buf->data;
         if (s->state == SSL23_ST_CW_CLNT_HELLO_A) {
                 arc4random_buf(s->s3->client_random, SSL3_RANDOM_SIZE);
 
-                if (version == TLS1_2_VERSION) {
-                        version_major = TLS1_2_VERSION_MAJOR;
-                        version_minor = TLS1_2_VERSION_MINOR;
-                } else if (version == TLS1_1_VERSION) {
-                        version_major = TLS1_1_VERSION_MAJOR;
-                        version_minor = TLS1_1_VERSION_MINOR;
-                } else if (version == TLS1_VERSION) {
-                        version_major = TLS1_VERSION_MAJOR;
-                        version_minor = TLS1_VERSION_MINOR;
-                } else {
+                if (ssl_enabled_version_range(s, NULL, &version) == -1) {
                         SSLerr(SSL_F_SSL23_CLIENT_HELLO,
                             SSL_R_NO_PROTOCOLS_AVAILABLE);
                         return (-1);
@@ -283,8 +255,8 @@ ssl23_client_hello(SSL *s)
                  */
                 d = p = &(buf[SSL3_RT_HEADER_LENGTH + SSL3_HM_HEADER_LENGTH]);
 
-                *(p++) = version_major;
-                *(p++) = version_minor;
+                *(p++) = version >> 8;
+                *(p++) = version & 0xff;
 
                 /* Random stuff */
                 memcpy(p, s->s3->client_random, SSL3_RANDOM_SIZE);
@@ -334,7 +306,7 @@ ssl23_client_hello(SSL *s)
                 /* fill in 5-byte record header */
                 d = buf;
                 *(d++) = SSL3_RT_HANDSHAKE;
-                *(d++) = version_major;
+                *(d++) = version >> 8;
 
                 /*
                  * Some servers hang if we use long client hellos
@@ -343,7 +315,7 @@ ssl23_client_hello(SSL *s)
                 if (TLS1_get_client_version(s) > TLS1_VERSION)
                         *(d++) = 1;
                 else
-                        *(d++) = version_minor;
+                        *(d++) = version & 0xff;
                 s2n((int)l, d);
 
                 /* number of bytes to write */
@@ -362,8 +334,7 @@ ssl23_client_hello(SSL *s)
 
         if ((ret >= 2) && s->msg_callback) {
                 /* Client Hello has been sent; tell msg_callback */
-
-                s->msg_callback(1, version, SSL3_RT_HANDSHAKE,
+                s->msg_callback(1, s->client_version, SSL3_RT_HANDSHAKE,
                     s->init_buf->data + 5, ret - 5, s, s->msg_callback_arg);
         }
 
diff --git a/src/lib/libssl/ssl_lib.c b/src/lib/libssl/ssl_lib.c
index 5d93a3bc13..11f46161a9 100644
--- a/src/lib/libssl/ssl_lib.c
+++ b/src/lib/libssl/ssl_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_lib.c,v 1.122 2016/12/04 14:32:30 jsing Exp $ */
+/* $OpenBSD: ssl_lib.c,v 1.123 2016/12/30 16:57:01 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -2484,6 +2484,48 @@ SSL_get_version(const SSL *s)
         return ssl_version_string(s->version);
 }
 
+int
+ssl_enabled_version_range(SSL *s, uint16_t *min_ver, uint16_t *max_ver)
+{
+        uint16_t min_version, max_version;
+
+        /*
+         * The enabled versions have to be a contiguous range, which means we
+         * cannot enable and disable single versions at our whim, even though
+         * this is what the OpenSSL flags allow. The historical way this has
+         * been handled is by making a flag mean that all higher versions
+         * are disabled, if any version lower than the flag is enabled.
+         */
+
+        min_version = 0;
+        max_version = TLS1_2_VERSION;
+
+        if ((s->options & SSL_OP_NO_TLSv1) == 0)
+                min_version = TLS1_VERSION;
+        else if ((s->options & SSL_OP_NO_TLSv1_1) == 0)
+                min_version = TLS1_1_VERSION;
+        else if ((s->options & SSL_OP_NO_TLSv1_2) == 0)
+                min_version = TLS1_2_VERSION;
+
+        if ((s->options & SSL_OP_NO_TLSv1_2) && min_version < TLS1_2_VERSION)
+                max_version = TLS1_1_VERSION;
+        if ((s->options & SSL_OP_NO_TLSv1_1) && min_version < TLS1_1_VERSION)
+                max_version = TLS1_VERSION;
+        if ((s->options & SSL_OP_NO_TLSv1) && min_version < TLS1_VERSION)
+                max_version = 0;
+
+        /* Everything has been disabled... */
+        if (min_version == 0 || max_version == 0)
+                return -1;
+
+        if (min_ver != NULL)
+                *min_ver = min_version;
+        if (max_ver != NULL)
+                *max_ver = max_version;
+
+        return 0;
+}
+
 uint16_t
 ssl_max_server_version(SSL *s)
 {
diff --git a/src/lib/libssl/ssl_locl.h b/src/lib/libssl/ssl_locl.h
index de977846a4..e8fbd23572 100644
--- a/src/lib/libssl/ssl_locl.h
+++ b/src/lib/libssl/ssl_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_locl.h,v 1.142 2016/12/30 15:12:45 jsing Exp $ */
+/* $OpenBSD: ssl_locl.h,v 1.143 2016/12/30 16:57:01 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -497,6 +497,7 @@ extern SSL3_ENC_METHOD ssl3_undef_enc_method;
 extern SSL_CIPHER ssl3_ciphers[];
 
 const char *ssl_version_string(int ver);
+int ssl_enabled_version_range(SSL *s, uint16_t *min_ver, uint16_t *max_ver);
 uint16_t ssl_max_server_version(SSL *s);
 
 extern SSL3_ENC_METHOD DTLSv1_enc_data;