[openssl-commits] [openssl] master update

Matt Caswell matt at openssl.org
Fri May 20 13:13:09 UTC 2016


The branch master has been updated
       via  464175692f1f00a9e5a87f040d0c59184d63b53b (commit)
      from  72106aaab439eddc69df29aa328fb5eeb2086f84 (commit)


- Log -----------------------------------------------------------------
commit 464175692f1f00a9e5a87f040d0c59184d63b53b
Author: Matt Caswell <matt at openssl.org>
Date:   Tue May 17 12:28:14 2016 +0100

    Simplify SSL BIO buffering logic
    
    The write BIO for handshake messages is bufferred so that we only write
    out to the network when we have a complete flight. There was some
    complexity in the buffering logic so that we switched buffering on and
    off at various points through out the handshake. The only real reason to
    do this was historically it complicated the state machine when you wanted
    to flush because you had to traverse through the "flush" state (in order
    to cope with NBIO). Where we knew up front that there was only going to
    be one message in the flight we switched off buffering to avoid that.
    
    In the new state machine there is no longer a need for a flush state so
    it is simpler just to have buffering on for the whole handshake. This
    also gives us the added benefit that we can simply call flush after every
    flight even if it only has one message in it. This means that BIO authors
    can implement their own buffering strategies and not have to be aware of
    the state of the SSL object (previously they would have to switch off
    their own buffering during the handshake because they could not rely on
    a flush being received when they really needed to write data out). This
    last point addresses GitHub Issue #322.
    
    Reviewed-by: Andy Polyakov <appro at openssl.org>

-----------------------------------------------------------------------

Summary of changes:
 ssl/ssl_lib.c            | 23 ++++++++---------------
 ssl/ssl_locl.h           |  4 ++--
 ssl/statem/statem.c      | 20 ++++++++++----------
 ssl/statem/statem_clnt.c | 15 ++-------------
 test/heartbeat_test.c    |  2 +-
 5 files changed, 23 insertions(+), 41 deletions(-)

diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 9fb6e89..83ad9ef 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -3220,34 +3220,27 @@ const COMP_METHOD *SSL_get_current_expansion(SSL *s)
 #endif
 }
 
-int ssl_init_wbio_buffer(SSL *s, int push)
+int ssl_init_wbio_buffer(SSL *s)
 {
     BIO *bbio;
 
     if (s->bbio == NULL) {
         bbio = BIO_new(BIO_f_buffer());
         if (bbio == NULL)
-            return (0);
+            return 0;
         s->bbio = bbio;
+        s->wbio = BIO_push(bbio, s->wbio);
     } else {
         bbio = s->bbio;
-        if (s->bbio == s->wbio)
-            s->wbio = BIO_pop(s->wbio);
+        (void)BIO_reset(bbio);
     }
-    (void)BIO_reset(bbio);
-/*      if (!BIO_set_write_buffer_size(bbio,16*1024)) */
+
     if (!BIO_set_read_buffer_size(bbio, 1)) {
         SSLerr(SSL_F_SSL_INIT_WBIO_BUFFER, ERR_R_BUF_LIB);
-        return (0);
-    }
-    if (push) {
-        if (s->wbio != bbio)
-            s->wbio = BIO_push(bbio, s->wbio);
-    } else {
-        if (s->wbio == bbio)
-            s->wbio = BIO_pop(bbio);
+        return 0;
     }
-    return (1);
+
+    return 1;
 }
 
 void ssl_free_wbio_buffer(SSL *s)
diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h
index 968a2ec..a1f5774 100644
--- a/ssl/ssl_locl.h
+++ b/ssl/ssl_locl.h
@@ -1787,7 +1787,7 @@ const SSL_METHOD *func_name(void)  \
         }
 
 struct openssl_ssl_test_functions {
-    int (*p_ssl_init_wbio_buffer) (SSL *s, int push);
+    int (*p_ssl_init_wbio_buffer) (SSL *s);
     int (*p_ssl3_setup_buffers) (SSL *s);
 # ifndef OPENSSL_NO_HEARTBEATS
     int (*p_dtls1_process_heartbeat) (SSL *s,
@@ -1963,7 +1963,7 @@ __owur int dtls1_shutdown(SSL *s);
 
 __owur int dtls1_dispatch_alert(SSL *s);
 
-__owur int ssl_init_wbio_buffer(SSL *s, int push);
+__owur int ssl_init_wbio_buffer(SSL *s);
 void ssl_free_wbio_buffer(SSL *s);
 
 __owur int tls1_change_cipher_state(SSL *s, int which);
diff --git a/ssl/statem/statem.c b/ssl/statem/statem.c
index d0ea55f..20353c3 100644
--- a/ssl/statem/statem.c
+++ b/ssl/statem/statem.c
@@ -320,20 +320,20 @@ static int state_machine(SSL *s, int server)
          */
         s->s3->change_cipher_spec = 0;
 
-        if (!server || st->state != MSG_FLOW_RENEGOTIATE) {
-                /*
-                 * Ok, we now need to push on a buffering BIO ...but not with
-                 * SCTP
-                 */
+
+        /*
+         * Ok, we now need to push on a buffering BIO ...but not with
+         * SCTP
+         */
 #ifndef OPENSSL_NO_SCTP
-                if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
+        if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
 #endif
-                    if (!ssl_init_wbio_buffer(s, server ? 1 : 0)) {
-                        goto end;
-                    }
+            if (!ssl_init_wbio_buffer(s)) {
+                goto end;
+            }
 
+        if (!server || st->state != MSG_FLOW_RENEGOTIATE)
             ssl3_init_finished_mac(s);
-        }
 
         if (server) {
             if (st->state != MSG_FLOW_RENEGOTIATE) {
diff --git a/ssl/statem/statem_clnt.c b/ssl/statem/statem_clnt.c
index 7591bb9..ecbc43b 100644
--- a/ssl/statem/statem_clnt.c
+++ b/ssl/statem/statem_clnt.c
@@ -437,20 +437,9 @@ WORK_STATE ossl_statem_client_post_work(SSL *s, WORK_STATE wst)
 
     switch(st->hand_state) {
     case TLS_ST_CW_CLNT_HELLO:
-        if (SSL_IS_DTLS(s) && s->d1->cookie_len > 0 && statem_flush(s) != 1)
+        if (wst == WORK_MORE_A && statem_flush(s) != 1)
             return WORK_MORE_A;
-#ifndef OPENSSL_NO_SCTP
-        /* Disable buffering for SCTP */
-        if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s))) {
-#endif
-            /*
-             * turn on buffering for the next lot of output
-             */
-            if (s->bbio != s->wbio)
-                s->wbio = BIO_push(s->bbio, s->wbio);
-#ifndef OPENSSL_NO_SCTP
-            }
-#endif
+
         if (SSL_IS_DTLS(s)) {
             /* Treat the next message as the first packet */
             s->first_packet = 1;
diff --git a/test/heartbeat_test.c b/test/heartbeat_test.c
index f92510a..906736c 100644
--- a/test/heartbeat_test.c
+++ b/test/heartbeat_test.c
@@ -101,7 +101,7 @@ static HEARTBEAT_TEST_FIXTURE set_up(const char *const test_case_name,
         goto fail;
     }
 
-    if (!ssl_init_wbio_buffer(fixture.s, 1)) {
+    if (!ssl_init_wbio_buffer(fixture.s)) {
         fprintf(stderr, "Failed to set up wbio buffer for test: %s\n",
                 test_case_name);
         setup_ok = 0;


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