patches.chromium/0012-paddingext2.patch

diff --git android-openssl.orig/ssl/d1_clnt.c android-openssl/ssl/d1_clnt.c
index 7e8077e..735e544 100644
--- android-openssl.orig/ssl/d1_clnt.c
+++ android-openssl/ssl/d1_clnt.c
@@ -874,7 +874,7 @@ int dtls1_client_hello(SSL *s)
 		*(p++)=0; /* Add the NULL method */
 
 #ifndef OPENSSL_NO_TLSEXT
-		if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
+		if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, 0)) == NULL)
 			{
 			SSLerr(SSL_F_DTLS1_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 			goto err;
diff --git android-openssl.orig/ssl/s23_clnt.c android-openssl/ssl/s23_clnt.c
index 08ee86d..750d208 100644
--- android-openssl.orig/ssl/s23_clnt.c
+++ android-openssl/ssl/s23_clnt.c
@@ -467,9 +467,9 @@ static int ssl23_client_hello(SSL *s)
 			/* create Client Hello in SSL 3.0/TLS 1.0 format */
 
 			/* do the record header (5 bytes) and handshake message
-			 * header (4 bytes) last. Note: the code to add the
-			 * padding extension in t1_lib.c depends on the size of
-			 * this prefix. */
+			 * header (4 bytes) last. Note: the final argument to
+			 * ssl_add_clienthello_tlsext below depends on the size
+			 * of this prefix. */
 			d = p = &(buf[9]);
 			
 			*(p++) = version_major;
@@ -526,7 +526,10 @@ static int ssl23_client_hello(SSL *s)
 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
 				return -1;
 				}
-			if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
+			/* The buffer includes the 5 byte record header, so
+			 * subtract it to compute hlen for
+			 * ssl_add_clienthello_tlsext. */
+			if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, p-buf-5)) == NULL)
 				{
 				SSLerr(SSL_F_SSL23_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 				return -1;
diff --git android-openssl.orig/ssl/s3_clnt.c android-openssl/ssl/s3_clnt.c
index d1b3224..640df80 100644
--- android-openssl.orig/ssl/s3_clnt.c
+++ android-openssl/ssl/s3_clnt.c
@@ -759,7 +759,7 @@ int ssl3_client_hello(SSL *s)
 			goto err;
 
 		/* Do the message type and length last.
-		 * Note: the code to add the padding extension in t1_lib.c
+		 * Note: the final argument to ssl_add_clienthello_tlsext below
 		 * depends on the size of this prefix. */
 		d=p= &(buf[4]);
 
@@ -867,7 +867,7 @@ int ssl3_client_hello(SSL *s)
 			SSLerr(SSL_F_SSL3_CLIENT_HELLO,SSL_R_CLIENTHELLO_TLSEXT);
 			goto err;
 			}
-		if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == NULL)
+		if ((p = ssl_add_clienthello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH, p-buf)) == NULL)
 			{
 			SSLerr(SSL_F_SSL3_CLIENT_HELLO,ERR_R_INTERNAL_ERROR);
 			goto err;
diff --git android-openssl.orig/ssl/ssl_locl.h android-openssl/ssl/ssl_locl.h
index 4e27d9e..531a291 100644
--- android-openssl.orig/ssl/ssl_locl.h
+++ android-openssl/ssl/ssl_locl.h
@@ -1127,7 +1127,7 @@ int tls1_ec_nid2curve_id(int nid);
 #endif /* OPENSSL_NO_EC */
 
 #ifndef OPENSSL_NO_TLSEXT
-unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit); 
+unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, size_t header_len);
 unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit); 
 int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al);
 int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al);
diff --git android-openssl.orig/ssl/t1_lib.c android-openssl/ssl/t1_lib.c
index a53d56b..3fe6612 100644
--- android-openssl.orig/ssl/t1_lib.c
+++ android-openssl/ssl/t1_lib.c
@@ -341,7 +341,10 @@ int tls12_get_req_sig_algs(SSL *s, unsigned char *p)
 	return (int)slen;
 	}
 
-unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit)
+/* header_len is the length of the ClientHello header written so far, used to
+ * compute padding. It does not include the record header. Pass 0 if no padding
+ * is to be done. */
+unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned char *limit, size_t header_len)
 	{
 	int extdatalen=0;
 	unsigned char *orig = buf;
@@ -664,27 +667,25 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *buf, unsigned c
 
 	/* Add padding to workaround bugs in F5 terminators.
 	 * See https://tools.ietf.org/html/draft-agl-tls-padding-02 */
-	{
-	int hlen = ret - (unsigned char *)s->init_buf->data;
-	/* The code in s23_clnt.c to build ClientHello messages includes the
-	 * 5-byte record header in the buffer, while the code in s3_clnt.c does
-	 * not. */
-	if (s->state == SSL23_ST_CW_CLNT_HELLO_A)
-		hlen -= 5;
-	if (hlen > 0xff && hlen < 0x200)
+	if (header_len > 0)
 		{
-		hlen = 0x200 - hlen;
-		if (hlen >= 4)
-			hlen -= 4;
-		else
-			hlen = 0;
+		header_len += ret - orig;
+		if (header_len > 0xff && header_len < 0x200)
+			{
+			size_t padding_len = 0x200 - header_len;
+			if (padding_len >= 4)
+				padding_len -= 4;
+			else
+				padding_len = 0;
+			if (limit - ret - 4 - (long)padding_len < 0)
+				return NULL;
 
-		s2n(TLSEXT_TYPE_padding, ret);
-		s2n(hlen, ret);
-		memset(ret, 0, hlen);
-		ret += hlen;
+			s2n(TLSEXT_TYPE_padding, ret);
+			s2n(padding_len, ret);
+			memset(ret, 0, padding_len);
+			ret += padding_len;
+			}
 		}
-	}
 
 
 	if ((extdatalen = ret-orig-2)== 0)