Convert various handshake message generation functions to CBB.

ok beck@ inoguchi@

4 files changed, 113 insertions, 56 deletions

diff --git a/lib/libssl/d1_srvr.c b/lib/libssl/d1_srvr.c
index 860a5fc4e3d..508e1317302 100644
--- a/lib/libssl/d1_srvr.c
+++ b/lib/libssl/d1_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: d1_srvr.c,v 1.84 2017/02/07 02:08:38 beck Exp $ */
+/* $OpenBSD: d1_srvr.c,v 1.85 2017/03/05 14:24:12 jsing Exp $ */
 /*
  * DTLS implementation written by Nagendra Modadugu
  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
@@ -693,31 +693,38 @@ end:
 int
 dtls1_send_hello_verify_request(SSL *s)
 {
-	unsigned char *d, *p;
+	CBB cbb, verify, cookie;
 
-	if (s->internal->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) {
-		d = p = ssl3_handshake_msg_start(s,
-		    DTLS1_MT_HELLO_VERIFY_REQUEST);
-
-		*(p++) = s->version >> 8;
-		*(p++) = s->version & 0xFF;
+	memset(&cbb, 0, sizeof(cbb));
 
+	if (s->internal->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) {
 		if (s->ctx->internal->app_gen_cookie_cb == NULL ||
-		    s->ctx->internal->app_gen_cookie_cb(s,
-			D1I(s)->cookie, &(D1I(s)->cookie_len)) == 0) {
+		    s->ctx->internal->app_gen_cookie_cb(s, D1I(s)->cookie,
+			&(D1I(s)->cookie_len)) == 0) {
 			SSLerror(s, ERR_R_INTERNAL_ERROR);
 			return 0;
 		}
 
-		*(p++) = (unsigned char) D1I(s)->cookie_len;
-		memcpy(p, D1I(s)->cookie, D1I(s)->cookie_len);
-		p += D1I(s)->cookie_len;
-
-		ssl3_handshake_msg_finish(s, p - d);
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &verify,
+		    DTLS1_MT_HELLO_VERIFY_REQUEST))
+			goto err;
+		if (!CBB_add_u16(&verify, s->version))
+			goto err;
+		if (!CBB_add_u8_length_prefixed(&verify, &cookie))
+			goto err;
+		if (!CBB_add_bytes(&cookie, D1I(s)->cookie, D1I(s)->cookie_len))
+			goto err;
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
 	}
 
 	/* s->internal->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
diff --git a/lib/libssl/ssl_both.c b/lib/libssl/ssl_both.c
index 14fd121d53b..d1a0879b729 100644
--- a/lib/libssl/ssl_both.c
+++ b/lib/libssl/ssl_both.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_both.c,v 1.6 2017/02/07 02:08:38 beck Exp $ */
+/* $OpenBSD: ssl_both.c,v 1.7 2017/03/05 14:24:12 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -166,9 +166,11 @@ ssl3_do_write(SSL *s, int type)
 int
 ssl3_send_finished(SSL *s, int a, int b, const char *sender, int slen)
 {
-	unsigned char *p;
+	CBB cbb, finished;
 	int md_len;
 
+	memset(&cbb, 0, sizeof(cbb));
+
 	if (s->internal->state == a) {
 		md_len = TLS1_FINISH_MAC_LENGTH;
 		OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);
@@ -189,14 +191,23 @@ ssl3_send_finished(SSL *s, int a, int b, const char *sender, int slen)
 			S3I(s)->previous_server_finished_len = md_len;
 		}
 
-		p = ssl3_handshake_msg_start(s, SSL3_MT_FINISHED);
-		memcpy(p, S3I(s)->tmp.finish_md, md_len);
-		ssl3_handshake_msg_finish(s, md_len);
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &finished,
+		    SSL3_MT_FINISHED))
+                        goto err;
+		if (!CBB_add_bytes(&finished, S3I(s)->tmp.finish_md, md_len))
+			goto err;
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = b;
 	}
 
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
 
 /*
diff --git a/lib/libssl/ssl_clnt.c b/lib/libssl/ssl_clnt.c
index 65939141a27..f46b66c3721 100644
--- a/lib/libssl/ssl_clnt.c
+++ b/lib/libssl/ssl_clnt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_clnt.c,v 1.8 2017/03/04 16:15:02 jsing Exp $ */
+/* $OpenBSD: ssl_clnt.c,v 1.9 2017/03/05 14:24:12 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -2619,27 +2619,40 @@ err:
 int
 ssl3_send_next_proto(SSL *s)
 {
-	unsigned int	 len, padding_len;
-	unsigned char	*d, *p;
+	CBB cbb, nextproto, npn, padding;
+	size_t pad_len;
+	uint8_t *pad;
 
-	if (s->internal->state == SSL3_ST_CW_NEXT_PROTO_A) {
-		d = p = ssl3_handshake_msg_start(s, SSL3_MT_NEXT_PROTO);
+	memset(&cbb, 0, sizeof(cbb));
 
-		len = s->internal->next_proto_negotiated_len;
-		padding_len = 32 - ((len + 2) % 32);
-		*(p++) = len;
-		memcpy(p, s->internal->next_proto_negotiated, len);
-		p += len;
-		*(p++) = padding_len;
-		memset(p, 0, padding_len);
-		p += padding_len;
+	if (s->internal->state == SSL3_ST_CW_NEXT_PROTO_A) {
+		pad_len = 32 - ((s->internal->next_proto_negotiated_len + 2) % 32);
 
-		ssl3_handshake_msg_finish(s, p - d);
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &nextproto,
+		    SSL3_MT_NEXT_PROTO))
+			goto err;
+		if (!CBB_add_u8_length_prefixed(&nextproto, &npn))
+			goto err;
+		if (!CBB_add_bytes(&npn, s->internal->next_proto_negotiated,
+		    s->internal->next_proto_negotiated_len))
+			goto err;
+		if (!CBB_add_u8_length_prefixed(&nextproto, &padding))
+			goto err;
+		if (!CBB_add_space(&padding, &pad, pad_len))
+			goto err;
+		memset(pad, 0, pad_len);
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = SSL3_ST_CW_NEXT_PROTO_B;
 	}
 
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
 
 /*
diff --git a/lib/libssl/ssl_srvr.c b/lib/libssl/ssl_srvr.c
index ddf8755707b..09ea6571748 100644
--- a/lib/libssl/ssl_srvr.c
+++ b/lib/libssl/ssl_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_srvr.c,v 1.8 2017/03/01 14:01:24 jsing Exp $ */
+/* $OpenBSD: ssl_srvr.c,v 1.9 2017/03/05 14:24:12 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -705,15 +705,27 @@ end:
 int
 ssl3_send_hello_request(SSL *s)
 {
+	CBB cbb, hello;
+
+	memset(&cbb, 0, sizeof(cbb));
+
 	if (s->internal->state == SSL3_ST_SW_HELLO_REQ_A) {
-		ssl3_handshake_msg_start(s, SSL3_MT_HELLO_REQUEST);
-		ssl3_handshake_msg_finish(s, 0);
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &hello,
+		    SSL3_MT_HELLO_REQUEST))
+			goto err;
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = SSL3_ST_SW_HELLO_REQ_B;
 	}
 
 	/* SSL3_ST_SW_HELLO_REQ_B */
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
 
 int
@@ -1166,15 +1178,27 @@ ssl3_send_server_hello(SSL *s)
 int
 ssl3_send_server_done(SSL *s)
 {
+	CBB cbb, done;
+
+	memset(&cbb, 0, sizeof(cbb));
+
 	if (s->internal->state == SSL3_ST_SW_SRVR_DONE_A) {
-		ssl3_handshake_msg_start(s, SSL3_MT_SERVER_DONE);
-		ssl3_handshake_msg_finish(s, 0);
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &done,
+		    SSL3_MT_SERVER_DONE))
+			goto err;
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = SSL3_ST_SW_SRVR_DONE_B;
 	}
 
 	/* SSL3_ST_SW_SRVR_DONE_B */
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
 
 int
@@ -2718,32 +2742,34 @@ ssl3_send_newsession_ticket(SSL *s)
 int
 ssl3_send_cert_status(SSL *s)
 {
-	unsigned char *p;
+	CBB cbb, certstatus, ocspresp;
+
+	memset(&cbb, 0, sizeof(cbb));
 
 	if (s->internal->state == SSL3_ST_SW_CERT_STATUS_A) {
-		/*
-		 * Grow buffer if need be: the length calculation is as
- 		 * follows 1 (message type) + 3 (message length) +
- 		 * 1 (ocsp response type) + 3 (ocsp response length)
- 		 * + (ocsp response)
- 		 */
-		if (!BUF_MEM_grow(s->internal->init_buf, SSL3_HM_HEADER_LENGTH + 4 +
+		if (!ssl3_handshake_msg_start_cbb(s, &cbb, &certstatus,
+		    SSL3_MT_CERTIFICATE_STATUS))
+			goto err;
+		if (!CBB_add_u8(&certstatus, s->tlsext_status_type))
+			goto err;
+		if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp))
+			goto err;
+		if (!CBB_add_bytes(&ocspresp, s->internal->tlsext_ocsp_resp,
 		    s->internal->tlsext_ocsp_resplen))
-			return (-1);
-
-		p = ssl3_handshake_msg_start(s, SSL3_MT_CERTIFICATE_STATUS);
-
-		*(p++) = s->tlsext_status_type;
-		l2n3(s->internal->tlsext_ocsp_resplen, p);
-		memcpy(p, s->internal->tlsext_ocsp_resp, s->internal->tlsext_ocsp_resplen);
-
-		ssl3_handshake_msg_finish(s, s->internal->tlsext_ocsp_resplen + 4);
+			goto err;
+		if (!ssl3_handshake_msg_finish_cbb(s, &cbb))
+			goto err;
 
 		s->internal->state = SSL3_ST_SW_CERT_STATUS_B;
 	}
 
 	/* SSL3_ST_SW_CERT_STATUS_B */
 	return (ssl3_handshake_write(s));
+
+ err:
+	CBB_cleanup(&cbb);
+
+	return (-1);
 }
 
 /*