Remove workaround for TLS padding bug from SSLeay days.

OpenSSL doesn't remember which clients were impacted and the
functionality has been broken in their stable releases for 2 years.

Based on OpenSSL commit a8e4ac6a2fe67c19672ecf0c6aeafa15801ce3a5.

ok jsing@

6 files changed, 12 insertions, 37 deletions

diff --git a/lib/libssl/d1_enc.c b/lib/libssl/d1_enc.c
index 7eac48785e4..c58e109ae57 100644
--- a/lib/libssl/d1_enc.c
+++ b/lib/libssl/d1_enc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: d1_enc.c,v 1.9 2014/12/14 15:30:50 jsing Exp $ */
+/* $OpenBSD: d1_enc.c,v 1.10 2015/07/17 07:04:40 doug Exp $ */
 /*
  * DTLS implementation written by Nagendra Modadugu
  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
@@ -187,10 +187,6 @@ dtls1_enc(SSL *s, int send)
 
 			/* we need to add 'i' padding bytes of value j */
 			j = i - 1;
-			if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG) {
-				if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
-					j++;
-			}
 			for (k = (int)l; k < (int)(l + i); k++)
 				rec->input[k] = j;
 			l += i;
diff --git a/lib/libssl/doc/SSL_CTX_set_options.3 b/lib/libssl/doc/SSL_CTX_set_options.3
index 53a7a6c9c06..922522a33c1 100644
--- a/lib/libssl/doc/SSL_CTX_set_options.3
+++ b/lib/libssl/doc/SSL_CTX_set_options.3
@@ -1,7 +1,7 @@
 .\"
-.\"	$OpenBSD: SSL_CTX_set_options.3,v 1.6 2015/06/15 05:32:58 doug Exp $
+.\"	$OpenBSD: SSL_CTX_set_options.3,v 1.7 2015/07/17 07:04:40 doug Exp $
 .\"
-.Dd $Mdocdate: June 15 2015 $
+.Dd $Mdocdate: July 17 2015 $
 .Dt SSL_CTX_SET_OPTIONS 3
 .Os
 .Sh NAME
@@ -125,7 +125,9 @@ this option has no effect.
 .It Dv SSL_OP_TLS_D5_BUG
 \&...
 .It Dv SSL_OP_TLS_BLOCK_PADDING_BUG
-\&...
+As of
+.Ox 5.8 ,
+this option has no effect.
 .It Dv SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
 Disables a countermeasure against a SSL 3.0/TLS 1.0 protocol vulnerability
 affecting CBC ciphers, which cannot be handled by some broken SSL
diff --git a/lib/libssl/s3_cbc.c b/lib/libssl/s3_cbc.c
index fd4781b64cc..57485caacf1 100644
--- a/lib/libssl/s3_cbc.c
+++ b/lib/libssl/s3_cbc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: s3_cbc.c,v 1.9 2014/12/15 00:46:53 doug Exp $ */
+/* $OpenBSD: s3_cbc.c,v 1.10 2015/07/17 07:04:40 doug Exp $ */
 /* ====================================================================
  * Copyright (c) 2012 The OpenSSL Project.  All rights reserved.
  *
@@ -165,24 +165,6 @@ tls1_cbc_remove_padding(const SSL* s, SSL3_RECORD *rec, unsigned block_size,
 
 	padding_length = rec->data[rec->length - 1];
 
-	/* NB: if compression is in operation the first packet may not be of
-	 * even length so the padding bug check cannot be performed. This bug
-	 * workaround has been around since SSLeay so hopefully it is either
-	 * fixed now or no buggy implementation supports compression [steve]
-	 * (We don't support compression either, so it's not in operation.)
-	 */
-	if ((s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)) {
-		/* First packet is even in size, so check */
-		if ((memcmp(s->s3->read_sequence, "\0\0\0\0\0\0\0\0",
-		    SSL3_SEQUENCE_SIZE) == 0) && !(padding_length & 1)) {
-			s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
-		}
-		if ((s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG) &&
-		    padding_length > 0) {
-			padding_length--;
-		}
-	}
-
 	if (EVP_CIPHER_flags(s->enc_read_ctx->cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) {
 		/* padding is already verified */
 		rec->length -= padding_length + 1;
diff --git a/lib/libssl/ssl.h b/lib/libssl/ssl.h
index c47ae4632fe..84154a51765 100644
--- a/lib/libssl/ssl.h
+++ b/lib/libssl/ssl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl.h,v 1.87 2015/06/20 12:29:39 jsing Exp $ */
+/* $OpenBSD: ssl.h,v 1.88 2015/07/17 07:04:41 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -522,7 +522,6 @@ struct ssl_session_st {
 #define SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER		0x00000020L
 #define SSL_OP_SAFARI_ECDHE_ECDSA_BUG			0x00000040L
 #define SSL_OP_TLS_D5_BUG				0x00000100L
-#define SSL_OP_TLS_BLOCK_PADDING_BUG			0x00000200L
 
 /* Disable SSL 3.0/TLS 1.0 CBC vulnerability workaround that was added
  * in OpenSSL 0.9.6d.  Usually (depending on the application protocol)
@@ -578,7 +577,6 @@ struct ssl_session_st {
      SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER | \
      SSL_OP_SAFARI_ECDHE_ECDSA_BUG | \
      SSL_OP_TLS_D5_BUG | \
-     SSL_OP_TLS_BLOCK_PADDING_BUG | \
      SSL_OP_CRYPTOPRO_TLSEXT_BUG)
 
 /* Obsolete flags kept for compatibility. No sane code should use them. */
@@ -594,6 +592,7 @@ struct ssl_session_st {
 #define SSL_OP_PKCS1_CHECK_2				0x0
 #define SSL_OP_SSLEAY_080_CLIENT_DH_BUG			0x0
 #define SSL_OP_SSLREF2_REUSE_CERT_TYPE_BUG		0x0
+#define SSL_OP_TLS_BLOCK_PADDING_BUG			0x0
 
 /* Allow SSL_write(..., n) to return r with 0 < r < n (i.e. report success
  * when just a single record has been written): */
diff --git a/lib/libssl/ssl3.h b/lib/libssl/ssl3.h
index 265d18810e4..8bcf9e37e82 100644
--- a/lib/libssl/ssl3.h
+++ b/lib/libssl/ssl3.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl3.h,v 1.37 2015/06/18 22:51:05 doug Exp $ */
+/* $OpenBSD: ssl3.h,v 1.38 2015/07/17 07:04:41 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -351,7 +351,7 @@ typedef struct ssl3_buffer_st {
 #define SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS	0x0001
 #define SSL3_FLAGS_DELAY_CLIENT_FINISHED	0x0002
 #define SSL3_FLAGS_POP_BUFFER			0x0004
-#define TLS1_FLAGS_TLS_PADDING_BUG		0x0008
+#define TLS1_FLAGS_TLS_PADDING_BUG		0x0
 #define TLS1_FLAGS_SKIP_CERT_VERIFY		0x0010
 #define TLS1_FLAGS_KEEP_HANDSHAKE		0x0020
 #define SSL3_FLAGS_CCS_OK			0x0080
diff --git a/lib/libssl/t1_enc.c b/lib/libssl/t1_enc.c
index b48e248b239..5cd1688a37f 100644
--- a/lib/libssl/t1_enc.c
+++ b/lib/libssl/t1_enc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: t1_enc.c,v 1.78 2015/06/17 14:27:56 jsing Exp $ */
+/* $OpenBSD: t1_enc.c,v 1.79 2015/07/17 07:04:41 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -875,10 +875,6 @@ tls1_enc(SSL *s, int send)
 
 			/* we need to add 'i' padding bytes of value j */
 			j = i - 1;
-			if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG) {
-				if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
-					j++;
-			}
 			for (k = (int)l; k < (int)(l + i); k++)
 				rec->input[k] = j;
 			l += i;