Add return value to dh_generate_f().

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@501 7dcaeef0-15fb-0310-b436-a5af3365683c

include/libssh/priv.h

@@ -514,11 +514,11 @@ void ssh_set_error(void *error, int code, const char *descr, ...) PRINTF_ATTRIBU
 
 /* in dh.c */
 /* DH key generation */
-int dh_generate_e(SSH_SESSION *session);
 void ssh_print_bignum(const char *which,bignum num);
+int dh_generate_e(SSH_SESSION *session);
+int dh_generate_f(SSH_SESSION *session);
 int dh_generate_x(SSH_SESSION *session);
 int dh_generate_y(SSH_SESSION *session);
-void dh_generate_f(SSH_SESSION *session);
 
 int ssh_crypto_init(void);
 void ssh_crypto_finalize(void);

libssh/dh.c

@@ -285,22 +285,34 @@ int dh_generate_e(SSH_SESSION *session) {
   return 0;
 }
 
-void dh_generate_f(SSH_SESSION *session){
+int dh_generate_f(SSH_SESSION *session) {
 #ifdef HAVE_LIBCRYPTO
   bignum_CTX ctx = bignum_ctx_new();
+  if (ctx == NULL) {
+    return -1;
+  }
 #endif
+
   session->next_crypto->f = bignum_new();
+  if (session->next_crypto->f == NULL) {
+    return -1;
+  }
+
 #ifdef HAVE_LIBGCRYPT
   bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y, p);
 #elif defined HAVE_LIBCRYPTO
   bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y, p, ctx);
 #endif
+
 #ifdef DEBUG_CRYPTO
   ssh_print_bignum("f", session->next_crypto->f);
 #endif
+
 #ifdef HAVE_LIBCRYPTO
   bignum_ctx_free(ctx);
 #endif
+
+  return 0;
 }
 
 STRING *make_bignum_string(bignum num){

libssh/server.c

@@ -278,7 +278,10 @@ static int dh_handshake_server(SSH_SESSION *session){
       ssh_set_error(session,SSH_FATAL,"Could not create y number");
       return -1;
     }
-    dh_generate_f(session);
+    if (dh_generate_f(session) < 0) {
+      ssh_set_error(session,SSH_FATAL,"Could not create f number");
+      return -1;
+    }
     f=dh_get_f(session);
     switch(session->hostkeys){
         case TYPE_DSS: