fixing common off-by-one error with respect to maximum message size

[oweals/gnunet.git] / src / fs / fs_download.c

diff --git a/src/fs/fs_download.c b/src/fs/fs_download.c
index c3ab514d96017f88d728667c12b07a9af0b55f2a..057f57b538d705a59ffb9436070ed418dfdee66e 100644 (file)
--- a/src/fs/fs_download.c
+++ b/src/fs/fs_download.c
@@ -305,12 +305,10 @@ schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
   fh = NULL;
   if ( (dc->old_file_size > off) &&
-       (dc->filename != NULL) )
-    {
-      fh = GNUNET_DISK_file_open (dc->filename,
-                                 GNUNET_DISK_OPEN_READ,
-                                 GNUNET_DISK_PERM_NONE);
-    }
+       (dc->filename != NULL) )    
+    fh = GNUNET_DISK_file_open (dc->filename,
+                               GNUNET_DISK_OPEN_READ,
+                               GNUNET_DISK_PERM_NONE);    
   if ( (fh != NULL) &&
        (off  == 
        GNUNET_DISK_file_seek (fh,
@@ -332,15 +330,23 @@ schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
          GNUNET_HashCode query;
 
          GNUNET_CRYPTO_hash_to_aes_key (&key, &sk, &iv);
-         GNUNET_CRYPTO_aes_encrypt (block, len,
-                                    &sk,
-                                    &iv,
-                                    enc);
+         if (-1 == GNUNET_CRYPTO_aes_encrypt (block, len,
+                                              &sk,
+                                              &iv,
+                                              enc))
+           {
+             GNUNET_break (0);
+             goto do_download;
+           }
          GNUNET_CRYPTO_hash (enc, len, &query);
          if (0 == memcmp (&query,
                           &chk->query,
                           sizeof (GNUNET_HashCode)))
            {
+#if DEBUG_DOWNLOAD
+             GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                         "Matching block already present, no need for download!\n");
+#endif
              /* already got it! */
              prc.dc = dc;
              prc.data = enc;
@@ -358,9 +364,11 @@ schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
            {
              GNUNET_break_op (0);
            }
+         GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (fh));
          return;
        }
     }
+ do_download:
   if (fh != NULL)
     GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (fh));
   if (depth < dc->treedepth)
@@ -374,12 +382,18 @@ schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
 
   if ( (dc->th == NULL) &&
        (dc->client != NULL) )
-    dc->th = GNUNET_CLIENT_notify_transmit_ready (dc->client,
-                                                 sizeof (struct SearchMessage),
-                                                 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
-                                                 GNUNET_NO,
-                                                 &transmit_download_request,
-                                                 dc);
+    {
+#if DEBUG_DOWNLOAD
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Asking for transmission to FS service\n");
+#endif
+      dc->th = GNUNET_CLIENT_notify_transmit_ready (dc->client,
+                                                   sizeof (struct SearchMessage),
+                                                   GNUNET_CONSTANTS_SERVICE_TIMEOUT,
+                                                   GNUNET_NO,
+                                                   &transmit_download_request,
+                                                   dc);
+    }
 }
 
 
@@ -906,11 +920,16 @@ process_result_with_request (void *cls,
       ppos = ppos->next;
     }
   GNUNET_CRYPTO_hash_to_aes_key (&sm->chk.key, &skey, &iv);
-  GNUNET_CRYPTO_aes_decrypt (prc->data,
-                            prc->size,
-                            &skey,
-                            &iv,
-                            pt);
+  if (-1 == GNUNET_CRYPTO_aes_decrypt (prc->data,
+                                      prc->size,
+                                      &skey,
+                                      &iv,
+                                      pt))
+    {
+      GNUNET_break (0);
+      dc->emsg = GNUNET_strdup ("internal error decrypting content");
+      goto signal_error;
+    }
   off = compute_disk_offset (GNUNET_ntohll (dc->uri->data.chk.file_length),
                             sm->offset,
                             sm->depth,
@@ -1203,6 +1222,10 @@ transmit_download_request (void *cls,
   dc->th = NULL;
   if (NULL == buf)
     {
+#if DEBUG_DOWNLOAD
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Transmitting download request failed, trying to reconnect\n");
+#endif
       try_reconnect (dc);
       return 0;
     }
@@ -1326,6 +1349,10 @@ try_reconnect (struct GNUNET_FS_DownloadContext *dc)
   
   if (NULL != dc->client)
     {
+#if DEBUG_DOWNLOAD
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Moving all requests back to pending list\n");
+#endif
       if (NULL != dc->th)
        {
          GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th);
@@ -1337,6 +1364,10 @@ try_reconnect (struct GNUNET_FS_DownloadContext *dc)
       GNUNET_CLIENT_disconnect (dc->client, GNUNET_NO);
       dc->client = NULL;
     }
+#if DEBUG_DOWNLOAD
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+             "Will try to reconnect in 1s\n");
+#endif
   dc->task
     = GNUNET_SCHEDULER_add_delayed (dc->h->sched,
                                    GNUNET_TIME_UNIT_SECONDS,
@@ -1360,6 +1391,8 @@ activate_fs_download (void *cls,
   struct GNUNET_FS_ProgressInfo pi;
 
   GNUNET_assert (NULL != client);
+  GNUNET_assert (dc->client == NULL);
+  GNUNET_assert (dc->th == NULL);
   dc->client = client;
   GNUNET_CLIENT_receive (client,
                         &receive_results,
@@ -1370,14 +1403,12 @@ activate_fs_download (void *cls,
   GNUNET_CONTAINER_multihashmap_iterate (dc->active,
                                         &retry_entry,
                                         dc);
-  if ( (dc->th == NULL) &&
-       (dc->client != NULL) )
-    dc->th = GNUNET_CLIENT_notify_transmit_ready (dc->client,
-                                                 sizeof (struct SearchMessage),
-                                                 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
-                                                 GNUNET_NO,
-                                                 &transmit_download_request,
-                                                 dc);
+  dc->th = GNUNET_CLIENT_notify_transmit_ready (dc->client,
+                                               sizeof (struct SearchMessage),
+                                               GNUNET_CONSTANTS_SERVICE_TIMEOUT,
+                                               GNUNET_NO,
+                                               &transmit_download_request,
+                                               dc);    
 }
 
 
@@ -1559,6 +1590,12 @@ GNUNET_FS_download_start (struct GNUNET_FS_Handle *h,
              "Download tree has depth %u\n",
              dc->treedepth);
 #endif
+  if (parent == NULL)
+    {
+      dc->top = GNUNET_FS_make_top (dc->h,
+                                   &GNUNET_FS_download_signal_suspend_,
+                                   dc);
+    }
   pi.status = GNUNET_FS_STATUS_DOWNLOAD_START;
   pi.value.download.specifics.start.meta = meta;
   GNUNET_FS_download_make_status_ (&pi, dc);
@@ -1568,11 +1605,6 @@ GNUNET_FS_download_start (struct GNUNET_FS_Handle *h,
                           1 /* 0 == CHK, 1 == top */); 
   GNUNET_FS_download_sync_ (dc);
   GNUNET_FS_download_start_downloading_ (dc);
-  if (parent == NULL)
-    dc->top = GNUNET_FS_make_top (dc->h,
-                                 &GNUNET_FS_download_signal_suspend_,
-                                 dc);
-
   return dc;
 }
 
@@ -1625,7 +1657,8 @@ GNUNET_FS_download_start_from_search (struct GNUNET_FS_Handle *h,
   struct GNUNET_FS_ProgressInfo pi;
   struct GNUNET_FS_DownloadContext *dc;
 
-  if (sr->download != NULL)
+  if ( (sr == NULL) ||
+       (sr->download != NULL) )
     {
       GNUNET_break (0);
       return NULL;
@@ -1709,6 +1742,7 @@ GNUNET_FS_download_start_from_search (struct GNUNET_FS_Handle *h,
 void
 GNUNET_FS_download_start_downloading_ (struct GNUNET_FS_DownloadContext *dc)
 {
+  GNUNET_assert (dc->job_queue == NULL);
   dc->job_queue = GNUNET_FS_queue_ (dc->h, 
                                    &activate_fs_download,
                                    &deactivate_fs_download,