ITS#7506 tls_o.c: Fix Diffie-Hellman parameter usage.

If a DHParamFile or olcDHParamFile is specified, then it will be used,
otherwise a hardcoded 1024 bit parameter will be used. This allows the use of
larger parameters; previously only 512 or 1024 bit parameters would ever be
used.

diff --git a/libraries/libldap/tls_o.c b/libraries/libldap/tls_o.c
index 2ecee465bd35d35d1a6b87c8f59b0d52ef5a91ef..367797e3df0ed07f572052fa55a2b6ad3bd14758 100644 (file)
--- a/libraries/libldap/tls_o.c
+++ b/libraries/libldap/tls_o.c
@@ -59,15 +59,13 @@ static int tlso_verify_cb( int ok, X509_STORE_CTX *ctx );
 static int tlso_verify_ok( int ok, X509_STORE_CTX *ctx );
 static RSA * tlso_tmp_rsa_cb( SSL *ssl, int is_export, int key_length );
 
-static DH * tlso_tmp_dh_cb( SSL *ssl, int is_export, int key_length );
-
-typedef struct dhplist {
-       struct dhplist *next;
-       int keylength;
-       DH *param;
-} dhplist;
-
-static dhplist *tlso_dhparams;
+/* From the OpenSSL 0.9.7 distro */
+static const char tlso_dhpem1024[] =
+"-----BEGIN DH PARAMETERS-----\n\
+MIGHAoGBAJf2QmHKtQXdKCjhPx1ottPb0PMTBH9A6FbaWMsTuKG/K3g6TG1Z1fkq\n\
+/Gz/PWk/eLI9TzFgqVAuPvr3q14a1aZeVUMTgo2oO5/y2UHe6VaJ+trqCTat3xlx\n\
+/mNbIK9HA2RgPC3gWfVLZQrY+gz3ASHHR5nXWHEyvpuZm7m3h+irAgEC\n\
+-----END DH PARAMETERS-----\n";
 
 static int tlso_seed_PRNG( const char *randfile );
 
@@ -76,7 +74,6 @@ static int tlso_seed_PRNG( const char *randfile );
  * provide mutexes for the OpenSSL library.
  */
 static ldap_pvt_thread_mutex_t tlso_mutexes[CRYPTO_NUM_LOCKS];
-static ldap_pvt_thread_mutex_t tlso_dh_mutex;
 
 static void tlso_locking_cb( int mode, int type, const char *file, int line )
 {
@@ -107,7 +104,6 @@ static void tlso_thr_init( void )
        for( i=0; i< CRYPTO_NUM_LOCKS ; i++ ) {
                ldap_pvt_thread_mutex_init( &tlso_mutexes[i] );
        }
-       ldap_pvt_thread_mutex_init( &tlso_dh_mutex );
        CRYPTO_set_locking_callback( tlso_locking_cb );
        CRYPTO_set_id_callback( tlso_thread_self );
 }
@@ -308,28 +304,32 @@ tlso_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
                return -1;
        }
 
-       if ( lo->ldo_tls_dhfile ) {
+       if (is_server) {
                DH *dh = NULL;
                BIO *bio;
-               dhplist *p;
+               SSL_CTX_set_options( ctx, SSL_OP_SINGLE_DH_USE );
+               if ( lo->ldo_tls_dhfile ) {
 
-               if (( bio=BIO_new_file( lt->lt_dhfile,"r" )) == NULL ) {
+                       if (( bio=BIO_new_file( lt->lt_dhfile,"r" )) == NULL ) {
+                               Debug( LDAP_DEBUG_ANY,
+                                       "TLS: could not use DH parameters file `%s'.\n",
+                                       lo->ldo_tls_dhfile,0,0);
+                               tlso_report_error();
+                               return -1;
+                       }
+               } else {
+                       bio = BIO_new_mem_buf( tlso_dhpem1024, -1 );
+               }
+               if (!( dh=PEM_read_bio_DHparams( bio, NULL, NULL, NULL ))) {
                        Debug( LDAP_DEBUG_ANY,
-                               "TLS: could not use DH parameters file `%s'.\n",
+                               "TLS: could not read DH parameters file `%s'.\n",
                                lo->ldo_tls_dhfile,0,0);
                        tlso_report_error();
+                       BIO_free( bio );
                        return -1;
                }
-               while (( dh=PEM_read_bio_DHparams( bio, NULL, NULL, NULL ))) {
-                       p = LDAP_MALLOC( sizeof(dhplist) );
-                       if ( p != NULL ) {
-                               p->keylength = DH_size( dh ) * 8;
-                               p->param = dh;
-                               p->next = tlso_dhparams;
-                               tlso_dhparams = p;
-                       }
-               }
                BIO_free( bio );
+               SSL_CTX_set_tmp_dh( ctx, dh );
        }
 
        if ( tlso_opt_trace ) {
@@ -349,9 +349,6 @@ tlso_ctx_init( struct ldapoptions *lo, struct ldaptls *lt, int is_server )
                lo->ldo_tls_require_cert == LDAP_OPT_X_TLS_ALLOW ?
                tlso_verify_ok : tlso_verify_cb );
        SSL_CTX_set_tmp_rsa_callback( ctx, tlso_tmp_rsa_cb );
-       if ( lo->ldo_tls_dhfile ) {
-               SSL_CTX_set_tmp_dh_callback( ctx, tlso_tmp_dh_cb );
-       }
 #ifdef HAVE_OPENSSL_CRL
        if ( lo->ldo_tls_crlcheck ) {
                X509_STORE *x509_s = SSL_CTX_get_cert_store( ctx );
@@ -1175,108 +1172,6 @@ tlso_seed_PRNG( const char *randfile )
        return 0;
 }
 
-struct dhinfo {
-       int keylength;
-       const char *pem;
-       size_t size;
-};
-
-
-/* From the OpenSSL 0.9.7 distro */
-static const char tlso_dhpem512[] =
-"-----BEGIN DH PARAMETERS-----\n\
-MEYCQQDaWDwW2YUiidDkr3VvTMqS3UvlM7gE+w/tlO+cikQD7VdGUNNpmdsp13Yn\n\
-a6LT1BLiGPTdHghM9tgAPnxHdOgzAgEC\n\
------END DH PARAMETERS-----\n";
-
-static const char tlso_dhpem1024[] =
-"-----BEGIN DH PARAMETERS-----\n\
-MIGHAoGBAJf2QmHKtQXdKCjhPx1ottPb0PMTBH9A6FbaWMsTuKG/K3g6TG1Z1fkq\n\
-/Gz/PWk/eLI9TzFgqVAuPvr3q14a1aZeVUMTgo2oO5/y2UHe6VaJ+trqCTat3xlx\n\
-/mNbIK9HA2RgPC3gWfVLZQrY+gz3ASHHR5nXWHEyvpuZm7m3h+irAgEC\n\
------END DH PARAMETERS-----\n";
-
-static const char tlso_dhpem2048[] =
-"-----BEGIN DH PARAMETERS-----\n\
-MIIBCAKCAQEA7ZKJNYJFVcs7+6J2WmkEYb8h86tT0s0h2v94GRFS8Q7B4lW9aG9o\n\
-AFO5Imov5Jo0H2XMWTKKvbHbSe3fpxJmw/0hBHAY8H/W91hRGXKCeyKpNBgdL8sh\n\
-z22SrkO2qCnHJ6PLAMXy5fsKpFmFor2tRfCzrfnggTXu2YOzzK7q62bmqVdmufEo\n\
-pT8igNcLpvZxk5uBDvhakObMym9mX3rAEBoe8PwttggMYiiw7NuJKO4MqD1llGkW\n\
-aVM8U2ATsCun1IKHrRxynkE1/MJ86VHeYYX8GZt2YA8z+GuzylIOKcMH6JAWzMwA\n\
-Gbatw6QwizOhr9iMjZ0B26TE3X8LvW84wwIBAg==\n\
------END DH PARAMETERS-----\n";
-
-static const char tlso_dhpem4096[] =
-"-----BEGIN DH PARAMETERS-----\n\
-MIICCAKCAgEA/urRnb6vkPYc/KEGXWnbCIOaKitq7ySIq9dTH7s+Ri59zs77zty7\n\
-vfVlSe6VFTBWgYjD2XKUFmtqq6CqXMhVX5ElUDoYDpAyTH85xqNFLzFC7nKrff/H\n\
-TFKNttp22cZE9V0IPpzedPfnQkE7aUdmF9JnDyv21Z/818O93u1B4r0szdnmEvEF\n\
-bKuIxEHX+bp0ZR7RqE1AeifXGJX3d6tsd2PMAObxwwsv55RGkn50vHO4QxtTARr1\n\
-rRUV5j3B3oPMgC7Offxx+98Xn45B1/G0Prp11anDsR1PGwtaCYipqsvMwQUSJtyE\n\
-EOQWk+yFkeMe4vWv367eEi0Sd/wnC+TSXBE3pYvpYerJ8n1MceI5GQTdarJ77OW9\n\
-bGTHmxRsLSCM1jpLdPja5jjb4siAa6EHc4qN9c/iFKS3PQPJEnX7pXKBRs5f7AF3\n\
-W3RIGt+G9IVNZfXaS7Z/iCpgzgvKCs0VeqN38QsJGtC1aIkwOeyjPNy2G6jJ4yqH\n\
-ovXYt/0mc00vCWeSNS1wren0pR2EiLxX0ypjjgsU1mk/Z3b/+zVf7fZSIB+nDLjb\n\
-NPtUlJCVGnAeBK1J1nG3TQicqowOXoM6ISkdaXj5GPJdXHab2+S7cqhKGv5qC7rR\n\
-jT6sx7RUr0CNTxzLI7muV2/a4tGmj0PSdXQdsZ7tw7gbXlaWT1+MM2MCAQI=\n\
------END DH PARAMETERS-----\n";
-
-static const struct dhinfo tlso_dhpem[] = {
-       { 512, tlso_dhpem512, sizeof(tlso_dhpem512) },
-       { 1024, tlso_dhpem1024, sizeof(tlso_dhpem1024) },
-       { 2048, tlso_dhpem2048, sizeof(tlso_dhpem2048) },
-       { 4096, tlso_dhpem4096, sizeof(tlso_dhpem4096) },
-       { 0, NULL, 0 }
-};
-
-static DH *
-tlso_tmp_dh_cb( SSL *ssl, int is_export, int key_length )
-{
-       struct dhplist *p = NULL;
-       BIO *b = NULL;
-       DH *dh = NULL;
-       int i;
-
-       /* Do we have params of this length already? */
-       LDAP_MUTEX_LOCK( &tlso_dh_mutex );
-       for ( p = tlso_dhparams; p; p=p->next ) {
-               if ( p->keylength == key_length ) {
-                       LDAP_MUTEX_UNLOCK( &tlso_dh_mutex );
-                       return p->param;
-               }
-       }
-
-       /* No - check for hardcoded params */
-
-       for (i=0; tlso_dhpem[i].keylength; i++) {
-               if ( tlso_dhpem[i].keylength == key_length ) {
-                       b = BIO_new_mem_buf( (char *)tlso_dhpem[i].pem, tlso_dhpem[i].size );
-                       break;
-               }
-       }
-
-       if ( b ) {
-               dh = PEM_read_bio_DHparams( b, NULL, NULL, NULL );
-               BIO_free( b );
-       }
-
-       /* Generating on the fly is expensive/slow... */
-       if ( !dh ) {
-               dh = DH_generate_parameters( key_length, DH_GENERATOR_2, NULL, NULL );
-       }
-       if ( dh ) {
-               p = LDAP_MALLOC( sizeof(struct dhplist) );
-               if ( p != NULL ) {
-                       p->keylength = key_length;
-                       p->param = dh;
-                       p->next = tlso_dhparams;
-                       tlso_dhparams = p;
-               }
-       }
-
-       LDAP_MUTEX_UNLOCK( &tlso_dh_mutex );
-       return dh;
-}
 
 tls_impl ldap_int_tls_impl = {
        "OpenSSL",