DO NOT MERGE

Re-enable SSL's cut-through feature in Kraken. This is identical to
  https://android-git.corp.google.com/g/#change,49244
which is for Froyo.

Change-Id: I6df6b8dcdd9f27ad6af7978e0b0587ff886a0137
diff --git a/android.testssl/testssl b/android.testssl/testssl
index 049fe2f..5720c75 100755
--- a/android.testssl/testssl
+++ b/android.testssl/testssl
@@ -79,6 +79,8 @@
 echo test sslv2/sslv3 with both client and server authentication and small client and server buffers
 $ssltest -server_auth -client_auth -c_small_records -s_small_records $CA $extra || exit 1
 
+echo test sslv2/sslv3 with both client and server authentication and handshake cutthrough
+$ssltest -server_auth -client_auth -cutthrough $CA $extra || exit 1
 
 echo test sslv2 via BIO pair
 $ssltest -bio_pair -ssl2 $extra || exit 1
diff --git a/apps/s_client.c b/apps/s_client.c
index 2f743f0..c071658 100644
--- a/apps/s_client.c
+++ b/apps/s_client.c
@@ -248,6 +248,7 @@
 	BIO_printf(bio_err," -tlsextdebug      - hex dump of all TLS extensions received\n");
 	BIO_printf(bio_err," -status           - request certificate status from server\n");
 	BIO_printf(bio_err," -no_ticket        - disable use of RFC4507bis session tickets\n");
+	BIO_printf(bio_err," -cutthrough       - enable 1-RTT full-handshake for strong ciphers\n");
 #endif
 	BIO_printf(bio_err," -legacy_renegotiation - enable use of legacy renegotiation (dangerous)\n");
 	}
@@ -305,6 +306,7 @@
 	EVP_PKEY *key = NULL;
 	char *CApath=NULL,*CAfile=NULL,*cipher=NULL;
 	int reconnect=0,badop=0,verify=SSL_VERIFY_NONE,bugs=0;
+	int cutthrough=0;
 	int crlf=0;
 	int write_tty,read_tty,write_ssl,read_ssl,tty_on,ssl_pending;
 	SSL_CTX *ctx=NULL;
@@ -535,6 +537,8 @@
 		else if	(strcmp(*argv,"-no_ticket") == 0)
 			{ off|=SSL_OP_NO_TICKET; }
 #endif
+		else if (strcmp(*argv,"-cutthrough") == 0)
+			cutthrough=1;
 		else if (strcmp(*argv,"-serverpref") == 0)
 			off|=SSL_OP_CIPHER_SERVER_PREFERENCE;
 		else if (strcmp(*argv,"-legacy_renegotiation") == 0)
@@ -725,6 +729,15 @@
 	 */
 	if (sock_type == SOCK_DGRAM) SSL_CTX_set_read_ahead(ctx, 1);
 
+	/* Enable handshake cutthrough for client connections using
+	 * strong ciphers. */
+	if (cutthrough)
+		{
+		int ssl_mode = SSL_CTX_get_mode(ctx);
+		ssl_mode |= SSL_MODE_HANDSHAKE_CUTTHROUGH;
+		SSL_CTX_set_mode(ctx, ssl_mode);
+		}
+
 	if (state) SSL_CTX_set_info_callback(ctx,apps_ssl_info_callback);
 	if (cipher != NULL)
 		if(!SSL_CTX_set_cipher_list(ctx,cipher)) {
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index 4e4964e..c7167f1 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -563,6 +563,10 @@
 /* Use small read and write buffers: (a) lazy allocate read buffers for
  * large incoming records, and (b) limit the size of outgoing records. */
 #define SSL_MODE_SMALL_BUFFERS 0x00000010L
+/* When set, clients may send application data before receipt of CCS
+ * and Finished.  This mode enables full-handshakes to 'complete' in
+ * one RTT. */
+#define SSL_MODE_HANDSHAKE_CUTTHROUGH 0x00000020L
 
 /* Note: SSL[_CTX]_set_{options,mode} use |= op on the previous value,
  * they cannot be used to clear bits. */
@@ -1113,10 +1117,12 @@
 /* Is the SSL_connection established? */
 #define SSL_get_state(a)		SSL_state(a)
 #define SSL_is_init_finished(a)		(SSL_state(a) == SSL_ST_OK)
-#define SSL_in_init(a)			(SSL_state(a)&SSL_ST_INIT)
+#define SSL_in_init(a)			((SSL_state(a)&SSL_ST_INIT) && \
+                                  !SSL_cutthrough_complete(a))
 #define SSL_in_before(a)		(SSL_state(a)&SSL_ST_BEFORE)
 #define SSL_in_connect_init(a)		(SSL_state(a)&SSL_ST_CONNECT)
 #define SSL_in_accept_init(a)		(SSL_state(a)&SSL_ST_ACCEPT)
+int SSL_cutthrough_complete(const SSL *s);
 
 /* The following 2 states are kept in ssl->rstate when reads fail,
  * you should not need these */
diff --git a/include/openssl/ssl3.h b/include/openssl/ssl3.h
index bf71ef9..7c4ea8a 100644
--- a/include/openssl/ssl3.h
+++ b/include/openssl/ssl3.h
@@ -465,6 +465,7 @@
 /*client */
 /* extra state */
 #define SSL3_ST_CW_FLUSH		(0x100|SSL_ST_CONNECT)
+#define SSL3_ST_CUTTHROUGH_COMPLETE	(0x101|SSL_ST_CONNECT)
 /* write to server */
 #define SSL3_ST_CW_CLNT_HELLO_A		(0x110|SSL_ST_CONNECT)
 #define SSL3_ST_CW_CLNT_HELLO_B		(0x111|SSL_ST_CONNECT)
diff --git a/openssl.config b/openssl.config
index d6fc918..acf8d7b 100644
--- a/openssl.config
+++ b/openssl.config
@@ -74,9 +74,8 @@
         progs.patch                 \
         arm-asm.patch               \
         small_records.patch         \
+        handshake_cutthrough.patch  \
         bad_version.patch"
-# Disabled for compatibility b/2586347
-#       handshake_cutthrough.patch
 
 OPENSSL_PATCHES_progs_SOURCES="\
 	apps/progs.h \
diff --git a/ssl/s3_clnt.c b/ssl/s3_clnt.c
index e5138b6..2bfff13 100644
--- a/ssl/s3_clnt.c
+++ b/ssl/s3_clnt.c
@@ -182,6 +182,20 @@
 	
 	s->in_handshake++;
 	if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 
+	if (SSL_get_mode(s) & SSL_MODE_HANDSHAKE_CUTTHROUGH)
+		{
+		/* Renegotiation complicates the state machine */
+		s->s3->flags |= SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS;
+#if 0	/* Send app data in separate packet, otherwise, some particular site
+	 * (only one site so far) closes the socket.
+	 * Note: there is a very small chance that two TCP packets
+	 * could be arriving at server combined into a single TCP packet,
+	 * then trigger that site to break. We haven't encounter that though.
+	 */
+		/* Send app data along with CCS/Finished */
+		s->s3->flags |= SSL3_FLAGS_DELAY_CLIENT_FINISHED;
+#endif
+		}
 
 	for (;;)
 		{
@@ -450,14 +464,29 @@
 				}
 			else
 				{
-#ifndef OPENSSL_NO_TLSEXT
-				/* Allow NewSessionTicket if ticket expected */
-				if (s->tlsext_ticket_expected)
-					s->s3->tmp.next_state=SSL3_ST_CR_SESSION_TICKET_A;
+				if ((SSL_get_mode(s) & SSL_MODE_HANDSHAKE_CUTTHROUGH) && SSL_get_cipher_bits(s, NULL) >= 128)
+					{
+					if (s->s3->flags & SSL3_FLAGS_DELAY_CLIENT_FINISHED)
+						{
+						s->state=SSL3_ST_CUTTHROUGH_COMPLETE;
+						s->s3->flags|=SSL3_FLAGS_POP_BUFFER;
+						s->s3->delay_buf_pop_ret=0;
+						}
+					else
+						{
+						s->s3->tmp.next_state=SSL3_ST_CUTTHROUGH_COMPLETE;
+						}
+					}
 				else
+					{
+#ifndef OPENSSL_NO_TLSEXT
+					/* Allow NewSessionTicket if ticket expected */
+					if (s->tlsext_ticket_expected)
+						s->s3->tmp.next_state=SSL3_ST_CR_SESSION_TICKET_A;
+					else
 #endif
-				
-				s->s3->tmp.next_state=SSL3_ST_CR_FINISHED_A;
+						s->s3->tmp.next_state=SSL3_ST_CR_FINISHED_A;
+					}
 				}
 			s->init_num=0;
 			break;
@@ -505,6 +534,24 @@
 			s->state=s->s3->tmp.next_state;
 			break;
 
+		case SSL3_ST_CUTTHROUGH_COMPLETE:
+#ifndef OPENSSL_NO_TLSEXT
+			/* Allow NewSessionTicket if ticket expected */
+			if (s->tlsext_ticket_expected)
+				s->state=SSL3_ST_CR_SESSION_TICKET_A;
+			else
+#endif
+				s->state=SSL3_ST_CR_FINISHED_A;
+
+			/* SSL_write() will take care of flushing buffered data if
+			 * DELAY_CLIENT_FINISHED is set.
+			 */
+			if (!(s->s3->flags & SSL3_FLAGS_DELAY_CLIENT_FINISHED))
+				ssl_free_wbio_buffer(s);
+			ret = 1;
+			goto end;
+			/* break; */
+
 		case SSL_ST_OK:
 			/* clean a few things up */
 			ssl3_cleanup_key_block(s);
diff --git a/ssl/s3_lib.c b/ssl/s3_lib.c
index 8fa4ab0..592d6b9 100644
--- a/ssl/s3_lib.c
+++ b/ssl/s3_lib.c
@@ -2566,9 +2566,22 @@
 
 static int ssl3_read_internal(SSL *s, void *buf, int len, int peek)
 	{
-	int ret;
+	int n,ret;
 	
 	clear_sys_error();
+	if ((s->s3->flags & SSL3_FLAGS_POP_BUFFER) && (s->wbio == s->bbio))
+		{
+		/* Deal with an application that calls SSL_read() when handshake data
+		 * is yet to be written.
+		 */
+		if (BIO_wpending(s->wbio) > 0)
+			{
+			s->rwstate=SSL_WRITING;
+			n=BIO_flush(s->wbio);
+			if (n <= 0) return(n);
+			s->rwstate=SSL_NOTHING;
+			}
+		}
 	if (s->s3->renegotiate) ssl3_renegotiate_check(s);
 	s->s3->in_read_app_data=1;
 	ret=s->method->ssl_read_bytes(s,SSL3_RT_APPLICATION_DATA,buf,len,peek);
diff --git a/ssl/ssl.h b/ssl/ssl.h
index 4e4964e..c7167f1 100644
--- a/ssl/ssl.h
+++ b/ssl/ssl.h
@@ -563,6 +563,10 @@
 /* Use small read and write buffers: (a) lazy allocate read buffers for
  * large incoming records, and (b) limit the size of outgoing records. */
 #define SSL_MODE_SMALL_BUFFERS 0x00000010L
+/* When set, clients may send application data before receipt of CCS
+ * and Finished.  This mode enables full-handshakes to 'complete' in
+ * one RTT. */
+#define SSL_MODE_HANDSHAKE_CUTTHROUGH 0x00000020L
 
 /* Note: SSL[_CTX]_set_{options,mode} use |= op on the previous value,
  * they cannot be used to clear bits. */
@@ -1113,10 +1117,12 @@
 /* Is the SSL_connection established? */
 #define SSL_get_state(a)		SSL_state(a)
 #define SSL_is_init_finished(a)		(SSL_state(a) == SSL_ST_OK)
-#define SSL_in_init(a)			(SSL_state(a)&SSL_ST_INIT)
+#define SSL_in_init(a)			((SSL_state(a)&SSL_ST_INIT) && \
+                                  !SSL_cutthrough_complete(a))
 #define SSL_in_before(a)		(SSL_state(a)&SSL_ST_BEFORE)
 #define SSL_in_connect_init(a)		(SSL_state(a)&SSL_ST_CONNECT)
 #define SSL_in_accept_init(a)		(SSL_state(a)&SSL_ST_ACCEPT)
+int SSL_cutthrough_complete(const SSL *s);
 
 /* The following 2 states are kept in ssl->rstate when reads fail,
  * you should not need these */
diff --git a/ssl/ssl3.h b/ssl/ssl3.h
index bf71ef9..7c4ea8a 100644
--- a/ssl/ssl3.h
+++ b/ssl/ssl3.h
@@ -465,6 +465,7 @@
 /*client */
 /* extra state */
 #define SSL3_ST_CW_FLUSH		(0x100|SSL_ST_CONNECT)
+#define SSL3_ST_CUTTHROUGH_COMPLETE	(0x101|SSL_ST_CONNECT)
 /* write to server */
 #define SSL3_ST_CW_CLNT_HELLO_A		(0x110|SSL_ST_CONNECT)
 #define SSL3_ST_CW_CLNT_HELLO_B		(0x111|SSL_ST_CONNECT)
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 15650da..0ba658e 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -2752,7 +2752,17 @@
 	SSL_callback_ctrl(ssl, SSL_CTRL_SET_MSG_CALLBACK, (void (*)(void))cb);
 	}
 
-
+int SSL_cutthrough_complete(const SSL *s)
+	{
+	return (!s->server &&                 /* cutthrough only applies to clients */
+		!s->hit &&                        /* full-handshake */
+		s->version >= SSL3_VERSION &&
+		s->s3->in_read_app_data == 0 &&   /* cutthrough only applies to write() */
+		(SSL_get_mode((SSL*)s) & SSL_MODE_HANDSHAKE_CUTTHROUGH) &&  /* cutthrough enabled */
+		SSL_get_cipher_bits(s, NULL) >= 128 &&                      /* strong cipher choosen */
+		(s->state == SSL3_ST_CR_SESSION_TICKET_A ||                 /* ready to write app-data*/
+			s->state == SSL3_ST_CR_FINISHED_A));
+	}
 
 #if defined(_WINDLL) && defined(OPENSSL_SYS_WIN16)
 #include "../crypto/bio/bss_file.c"
diff --git a/ssl/ssltest.c b/ssl/ssltest.c
index 09d3502..cf23987 100644
--- a/ssl/ssltest.c
+++ b/ssl/ssltest.c
@@ -279,6 +279,7 @@
 	fprintf(stderr," -test_cipherlist - verifies the order of the ssl cipher lists\n");
 	fprintf(stderr," -c_small_records - enable client side use of small SSL record buffers\n");
 	fprintf(stderr," -s_small_records - enable server side use of small SSL record buffers\n");
+	fprintf(stderr," -cutthrough      - enable 1-RTT full-handshake for strong ciphers\n");
 	}
 
 static void print_details(SSL *c_ssl, const char *prefix)
@@ -436,6 +437,7 @@
 	int ssl_mode = 0;
 	int c_small_records=0;
 	int s_small_records=0;
+	int cutthrough = 0;
 
 	verbose = 0;
 	debug = 0;
@@ -632,6 +634,10 @@
 			{
 			s_small_records = 1;
 			}
+		else if (strcmp(*argv, "-cutthrough") == 0)
+			{
+			cutthrough = 1;
+			}
 		else
 			{
 			fprintf(stderr,"unknown option %s\n",*argv);
@@ -782,6 +788,13 @@
 		ssl_mode |= SSL_MODE_SMALL_BUFFERS;
 		SSL_CTX_set_mode(s_ctx, ssl_mode);
 		}
+	ssl_mode = 0;
+	if (cutthrough)
+		{
+		ssl_mode = SSL_CTX_get_mode(c_ctx);
+		ssl_mode = SSL_MODE_HANDSHAKE_CUTTHROUGH;
+		SSL_CTX_set_mode(c_ctx, ssl_mode);
+		}
 
 #ifndef OPENSSL_NO_DH
 	if (!no_dhe)