Add return values to generate_session_keys() and generate_one_key().

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@508 7dcaeef0-15fb-0310-b436-a5af3365683c

include/libssh/priv.h

@@ -533,7 +533,7 @@ int make_sessionid(SSH_SESSION *session);
 /* add data for the final cookie */
 int hashbufin_add_cookie(SSH_SESSION *session, unsigned char *cookie);
 int hashbufout_add_cookie(SSH_SESSION *session);
-void generate_session_keys(SSH_SESSION *session);
+int generate_session_keys(SSH_SESSION *session);
 /* returns 1 if server signature ok, 0 otherwise. The NEXT crypto is checked, not the current one */
 int signature_verify(SSH_SESSION *session,STRING *signature);
 bignum make_string_bn(STRING *string);

libssh/client.c

@@ -313,7 +313,10 @@ static int dh_handshake(SSH_SESSION *session) {
         goto error;
       }
 
-      generate_session_keys(session);
+      if (generate_session_keys(session) < 0) {
+        rc = SSH_ERROR;
+        goto error;
+      }
 
       /* Verify the host's signature. FIXME do it sooner */
       signature = session->dh_server_signature;

libssh/dh.c

@@ -662,48 +662,84 @@ int hashbufin_add_cookie(SSH_SESSION *session, unsigned char *cookie) {
   return 0;
 }
 
-/* TODO FIXME add return value for memory checks */
+static int generate_one_key(STRING *k,
-static void generate_one_key(STRING *k,unsigned char session_id[SHA_DIGEST_LEN],unsigned char output[SHA_DIGEST_LEN],char letter){
+    unsigned char session_id[SHA_DIGEST_LEN],
-    SHACTX ctx=sha1_init();
+    unsigned char output[SHA_DIGEST_LEN],
+    char letter) {
+  SHACTX ctx = NULL;
+
+  ctx = sha1_init();
   if (ctx == NULL) {
-      return;
+    return -1;
   }
+
   sha1_update(ctx, k, string_len(k) + 4);
   sha1_update(ctx, session_id, SHA_DIGEST_LEN);
   sha1_update(ctx, &letter, 1);
   sha1_update(ctx, session_id, SHA_DIGEST_LEN);
   sha1_final(output, ctx);
+
+  return 0;
 }
 
-/* TODO FIXME add return value for memory checks */
+int generate_session_keys(SSH_SESSION *session) {
-void generate_session_keys(SSH_SESSION *session){
+  STRING *k_string = NULL;
-    STRING *k_string;
+  SHACTX ctx = NULL;
-    SHACTX ctx;
+  int rc = -1;
+
   enter_function();
+
   k_string = make_bignum_string(session->next_crypto->k);
+  if (k_string == NULL) {
+    goto error;
+  }
 
   /* IV */
   if (session->client) {
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptIV,'A');
+    if (generate_one_key(k_string, session->next_crypto->session_id,
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptIV,'B');
+          session->next_crypto->encryptIV, 'A') < 0) {
+      goto error;
+    }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->decryptIV, 'B') < 0) {
+      goto error;
+    }
   } else {
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptIV,'A');
+    if (generate_one_key(k_string, session->next_crypto->session_id,
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptIV,'B');
+          session->next_crypto->decryptIV, 'A') < 0) {
+      goto error;
+    }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->encryptIV, 'B') < 0) {
+      goto error;
+    }
   }
   if (session->client) {
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptkey,'C');
+    if (generate_one_key(k_string, session->next_crypto->session_id,
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptkey,'D');
+          session->next_crypto->encryptkey, 'C') < 0) {
-    } else {
+      goto error;
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptkey,'C');
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptkey,'D');
     }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->decryptkey, 'D') < 0) {
+      goto error;
+    }
+  } else {
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->decryptkey, 'C') < 0) {
+      goto error;
+    }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->encryptkey, 'D') < 0) {
+      goto error;
+    }
+  }
+
   /* some ciphers need more than 20 bytes of input key */
   /* XXX verify it's ok for server implementation */
   if (session->next_crypto->out_cipher->keysize > SHA_DIGEST_LEN * 8) {
     ctx = sha1_init();
     if (ctx == NULL) {
-          leave_function();
+      goto error;
-          return;
     }
     sha1_update(ctx, k_string, string_len(k_string) + 4);
     sha1_update(ctx, session->next_crypto->session_id, SHA_DIGEST_LEN);
@@ -719,23 +755,42 @@ void generate_session_keys(SSH_SESSION *session){
     sha1_final(session->next_crypto->decryptkey + SHA_DIGEST_LEN, ctx);
   }
   if(session->client) {
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptMAC,'E');
+    if (generate_one_key(k_string, session->next_crypto->session_id,
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptMAC,'F');
+          session->next_crypto->encryptMAC, 'E') < 0) {
+      goto error;
+    }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->decryptMAC, 'F') < 0) {
+      goto error;
+    }
   } else {
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->decryptMAC,'E');
+    if (generate_one_key(k_string, session->next_crypto->session_id,
-        generate_one_key(k_string,session->next_crypto->session_id,session->next_crypto->encryptMAC,'F');
+          session->next_crypto->decryptMAC, 'E') < 0) {
+      goto error;
+    }
+    if (generate_one_key(k_string, session->next_crypto->session_id,
+          session->next_crypto->encryptMAC, 'F') < 0) {
+      goto error;
+    }
   }
 
 #ifdef DEBUG_CRYPTO
-    ssh_print_hexa("encrypt IV",session->next_crypto->encryptIV,SHA_DIGEST_LEN);
+  ssh_print_hexa("Encrypt IV", session->next_crypto->encryptIV, SHA_DIGEST_LEN);
-    ssh_print_hexa("decrypt IV",session->next_crypto->decryptIV,SHA_DIGEST_LEN);
+  ssh_print_hexa("Decrypt IV", session->next_crypto->decryptIV, SHA_DIGEST_LEN);
-    ssh_print_hexa("encryption key",session->next_crypto->encryptkey,session->next_crypto->out_cipher->keysize);
+  ssh_print_hexa("Encryption key", session->next_crypto->encryptkey,
-    ssh_print_hexa("decryption key",session->next_crypto->decryptkey,session->next_crypto->in_cipher->keysize);
+      session->next_crypto->out_cipher->keysize);
+  ssh_print_hexa("Decryption key", session->next_crypto->decryptkey,
+      session->next_crypto->in_cipher->keysize);
   ssh_print_hexa("Encryption MAC", session->next_crypto->encryptMAC, SHA_DIGEST_LEN);
   ssh_print_hexa("Decryption MAC", session->next_crypto->decryptMAC, 20);
 #endif
-    free(k_string);
+
+  rc = 0;
+error:
+  string_free(k_string);
   leave_function();
+
+  return rc;
 }
 
 /** \addtogroup ssh_session

libssh/server.c

@@ -330,7 +330,9 @@ static int dh_handshake_server(SSH_SESSION *session){
 
     packet_wait(session,SSH2_MSG_NEWKEYS,1);
     ssh_log(session, SSH_LOG_PACKET, "Got SSH_MSG_NEWKEYS");
-    generate_session_keys(session);
+    if (generate_session_keys(session) < 0) {
+      return -1;
+    }
     /* once we got SSH2_MSG_NEWKEYS we can switch next_crypto and current_crypto */
     if(session->current_crypto)
         crypto_free(session->current_crypto);