commit 5324d411da32d754a9658ff3eb5c1e59960d2bd9
author Manuel Pégourié-Gonnard <mpg@elzevir.fr> Fri Jun 26 18:20:34 2015 +0200
committer Manuel Pégourié-Gonnard <mpg@elzevir.fr> Mon Jun 29 18:54:28 2015 +0200
tree 30ac9742fda10936a4b87e064d82bedc3084b3a2
parent 7b209579c693eb12f3338fe03e29b7d889baeedb

Up min size of DHM params to 1024 bits

ChangeLog

diff --git a/ChangeLog b/ChangeLog
index 1ff0658..d2328b6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 PolarSSL ChangeLog
 
+= Version 1.2.15 released 2015-mm-dd
+
+Security
+   * Increase the minimum size of Diffie-Hellman parameters accepted by the
+     lient to 1024 bits, to protect against Logjam attack.
+
+Changes
+   * Add SSL_MIN_DHM_BYTES configuration parameter in config.h to choose the
+     minimum size of Diffie-Hellman parameters accepted by the client.
+
 = Version 1.2.14 released 2015-06-26
 
 Security

include/polarssl/config.h

diff --git a/include/polarssl/config.h b/include/polarssl/config.h
index 10b4fb1..3a18f8a 100644
--- a/include/polarssl/config.h
+++ b/include/polarssl/config.h
@@ -1017,6 +1017,7 @@
 // SSL options
 //
 #define SSL_MAX_CONTENT_LEN             16384 /**< Size of the input / output buffer */
+#define SSL_MIN_DHM_BYTES                 128 /**< Min size of the Diffie-Hellman prime */
 
 // X509 options
 //

include/polarssl/ssl.h

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 14ec0fd..e6cc2ad 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -130,6 +130,7 @@
  */
 #if !defined(POLARSSL_CONFIG_OPTIONS)
 #define SSL_MAX_CONTENT_LEN         16384   /**< Size of the input / output buffer */
+#define SSL_MIN_DHM_BYTES             128   /**< Min size of the Diffie-Hellman prime */
 #endif /* !POLARSSL_CONFIG_OPTIONS */
 
 /*

library/ssl_cli.c

diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 0817ea7..db9e179 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -778,7 +778,8 @@
         return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );
     }
 
-    if( ssl->handshake->dhm_ctx.len < 64 || ssl->handshake->dhm_ctx.len > 512 )
+    if( ssl->handshake->dhm_ctx.len < SSL_MIN_DHM_BYTES ||
+        ssl->handshake->dhm_ctx.len > 512 )
     {
         SSL_DEBUG_MSG( 1, ( "bad server key exchange message" ) );
         return( POLARSSL_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE );

tests/compat.sh

diff --git a/tests/compat.sh b/tests/compat.sh
index be1d720..b7170ff 100644
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -12,7 +12,7 @@
 then
     P_SERVER_ARGS="auth_mode=required crt_file=data_files/server1.crt key_file=data_files/server1.key ca_file=data_files/test-ca.crt"
     P_CLIENT_ARGS="crt_file=data_files/server2.crt key_file=data_files/server2.key ca_file=data_files/test-ca.crt"
-    O_SERVER_ARGS="-verify 10 -CAfile data_files/test-ca.crt -cert data_files/server1.crt -key data_files/server1.key"
+    O_SERVER_ARGS="-verify 10 -CAfile data_files/test-ca.crt -cert data_files/server1.crt -key data_files/server1.key -dhparam data_files/dhparams.pem"
     O_CLIENT_ARGS="-cert data_files/server2.crt -key data_files/server2.key -CAfile data_files/test-ca.crt"
 fi