From a62729888b9d8eafbfa952fca63a04100ed90f69 Mon Sep 17 00:00:00 2001
From: Paul Bakker
Date: Fri, 12 Apr 2013 13:13:43 +0200
Subject: [PATCH] Ability to specify allowed ciphersuites based on the protocol
version.
The ciphersuites parameter in the ssl_session structure changed from
'int *' to 'int **' and is now malloced in ssl_init() and freed in
ssl_free().
The new function ssl_set_ciphersuite_for_version() sets specific entries
inside this array. ssl_set_ciphersuite() sets all entries to the same
value.
---
ChangeLog | 3 +++
include/polarssl/ssl.h | 20 +++++++++++++++++++-
library/ssl_cli.c | 12 ++++++------
library/ssl_srv.c | 12 ++++++------
library/ssl_tls.c | 22 ++++++++++++++++++++--
5 files changed, 54 insertions(+), 15 deletions(-)
diff --git a/ChangeLog b/ChangeLog
index 18be08ab7..e007de42e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,9 @@
PolarSSL ChangeLog
= Branch 1.2
+Features
+ * Ability to specify allowed ciphersuites based on the protocol version.
+
Bugfix
* Fix for MPI assembly for ARM
diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 9746e276b..d5e8e1b45 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -491,7 +491,7 @@ struct _ssl_context
int verify_result; /*!< verification result */
int disable_renegotiation; /*!< enable/disable renegotiation */
int allow_legacy_renegotiation; /*!< allow legacy renegotiation */
- const int *ciphersuites; /*!< allowed ciphersuites */
+ const int **ciphersuites; /*!< allowed ciphersuites / version */
#if defined(POLARSSL_DHM_C)
mpi dhm_P; /*!< prime modulus for DHM */
@@ -718,12 +718,30 @@ void ssl_set_session( ssl_context *ssl, const ssl_session *session );
/**
* \brief Set the list of allowed ciphersuites
+ * (Overrides all version specific lists)
*
* \param ssl SSL context
* \param ciphersuites 0-terminated list of allowed ciphersuites
*/
void ssl_set_ciphersuites( ssl_context *ssl, const int *ciphersuites );
+/**
+ * \brief Set the list of allowed ciphersuites for a specific
+ * version of the protocol.
+ * (Only useful on the server side)
+ *
+ * \param ssl SSL context
+ * \param ciphersuites 0-terminated list of allowed ciphersuites
+ * \param major Major version number (only SSL_MAJOR_VERSION_3
+ * supported)
+ * \param minor Minor version number (SSL_MINOR_VERSION_0,
+ * SSL_MINOR_VERSION_1 and SSL_MINOR_VERSION_2,
+ * SSL_MINOR_VERSION_3 supported)
+ */
+void ssl_set_ciphersuites_for_version( ssl_context *ssl,
+ const int *ciphersuites,
+ int major, int minor );
+
/**
* \brief Set the data required to verify peer certificate
*
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 545906a2a..7019ed07b 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -119,7 +119,7 @@ static int ssl_write_client_hello( ssl_context *ssl )
SSL_DEBUG_MSG( 3, ( "client hello, session id len.: %d", n ) );
SSL_DEBUG_BUF( 3, "client hello, session id", buf + 39, n );
- for( n = 0; ssl->ciphersuites[n] != 0; n++ );
+ for( n = 0; ssl->ciphersuites[ssl->minor_ver][n] != 0; n++ );
if( ssl->renegotiation == SSL_INITIAL_HANDSHAKE ) n++;
*p++ = (unsigned char)( n >> 7 );
*p++ = (unsigned char)( n << 1 );
@@ -139,10 +139,10 @@ static int ssl_write_client_hello( ssl_context *ssl )
for( i = 0; i < n; i++ )
{
SSL_DEBUG_MSG( 3, ( "client hello, add ciphersuite: %2d",
- ssl->ciphersuites[i] ) );
+ ssl->ciphersuites[ssl->minor_ver][i] ) );
- *p++ = (unsigned char)( ssl->ciphersuites[i] >> 8 );
- *p++ = (unsigned char)( ssl->ciphersuites[i] );
+ *p++ = (unsigned char)( ssl->ciphersuites[ssl->minor_ver][i] >> 8 );
+ *p++ = (unsigned char)( ssl->ciphersuites[ssl->minor_ver][i] );
}
#if defined(POLARSSL_ZLIB_SUPPORT)
@@ -515,13 +515,13 @@ static int ssl_parse_server_hello( ssl_context *ssl )
i = 0;
while( 1 )
{
- if( ssl->ciphersuites[i] == 0 )
+ if( ssl->ciphersuites[ssl->minor_ver][i] == 0 )
{
SSL_DEBUG_MSG( 1, ( "bad server hello message" ) );
return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
}
- if( ssl->ciphersuites[i++] == ssl->session_negotiate->ciphersuite )
+ if( ssl->ciphersuites[ssl->minor_ver][i++] == ssl->session_negotiate->ciphersuite )
break;
}
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 325440d9d..1678e3146 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -359,13 +359,13 @@ static int ssl_parse_client_hello_v2( ssl_context *ssl )
}
}
- for( i = 0; ssl->ciphersuites[i] != 0; i++ )
+ for( i = 0; ssl->ciphersuites[ssl->minor_ver][i] != 0; i++ )
{
for( j = 0, p = buf + 6; j < ciph_len; j += 3, p += 3 )
{
if( p[0] == 0 &&
p[1] == 0 &&
- p[2] == ssl->ciphersuites[i] )
+ p[2] == ssl->ciphersuites[ssl->minor_ver][i] )
goto have_ciphersuite_v2;
}
}
@@ -375,7 +375,7 @@ static int ssl_parse_client_hello_v2( ssl_context *ssl )
return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
have_ciphersuite_v2:
- ssl->session_negotiate->ciphersuite = ssl->ciphersuites[i];
+ ssl->session_negotiate->ciphersuite = ssl->ciphersuites[ssl->minor_ver][i];
ssl_optimize_checksum( ssl, ssl->session_negotiate->ciphersuite );
/*
@@ -642,12 +642,12 @@ static int ssl_parse_client_hello( ssl_context *ssl )
/*
* Search for a matching ciphersuite
*/
- for( i = 0; ssl->ciphersuites[i] != 0; i++ )
+ for( i = 0; ssl->ciphersuites[ssl->minor_ver][i] != 0; i++ )
{
for( j = 0, p = buf + 41 + sess_len; j < ciph_len;
j += 2, p += 2 )
{
- if( p[0] == 0 && p[1] == ssl->ciphersuites[i] )
+ if( p[0] == 0 && p[1] == ssl->ciphersuites[ssl->minor_ver][i] )
goto have_ciphersuite;
}
}
@@ -657,7 +657,7 @@ static int ssl_parse_client_hello( ssl_context *ssl )
return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
have_ciphersuite:
- ssl->session_negotiate->ciphersuite = ssl->ciphersuites[i];
+ ssl->session_negotiate->ciphersuite = ssl->ciphersuites[ssl->minor_ver][i];
ssl_optimize_checksum( ssl, ssl->session_negotiate->ciphersuite );
ext = buf + 44 + sess_len + ciph_len + comp_len;
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index dde0155cb..9455ae2ec 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2952,7 +2952,8 @@ int ssl_init( ssl_context *ssl )
ssl->min_major_ver = SSL_MAJOR_VERSION_3;
ssl->min_minor_ver = SSL_MINOR_VERSION_0;
- ssl->ciphersuites = ssl_default_ciphersuites;
+ ssl->ciphersuites = malloc( sizeof(int *) * 4 );
+ ssl_set_ciphersuites( ssl, ssl_default_ciphersuites );
#if defined(POLARSSL_DHM_C)
if( ( ret = mpi_read_string( &ssl->dhm_P, 16,
@@ -3133,7 +3134,22 @@ void ssl_set_session( ssl_context *ssl, const ssl_session *session )
void ssl_set_ciphersuites( ssl_context *ssl, const int *ciphersuites )
{
- ssl->ciphersuites = ciphersuites;
+ ssl->ciphersuites[SSL_MINOR_VERSION_0] = ciphersuites;
+ ssl->ciphersuites[SSL_MINOR_VERSION_1] = ciphersuites;
+ ssl->ciphersuites[SSL_MINOR_VERSION_2] = ciphersuites;
+ ssl->ciphersuites[SSL_MINOR_VERSION_3] = ciphersuites;
+}
+
+void ssl_set_ciphersuites_for_version( ssl_context *ssl, const int *ciphersuites,
+ int major, int minor )
+{
+ if( major != SSL_MAJOR_VERSION_3 )
+ return;
+
+ if( minor < SSL_MINOR_VERSION_0 || minor > SSL_MINOR_VERSION_3 )
+ return;
+
+ ssl->ciphersuites[minor] = ciphersuites;
}
void ssl_set_ca_chain( ssl_context *ssl, x509_cert *ca_chain,
@@ -3897,6 +3913,8 @@ void ssl_free( ssl_context *ssl )
{
SSL_DEBUG_MSG( 2, ( "=> free" ) );
+ free( ssl->ciphersuites );
+
if( ssl->out_ctr != NULL )
{
memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );