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 ff3eb09e1477455806186e848b014c25d0aff4dd..057f57b538d705a59ffb9436070ed418dfdee66e 100644 (file)
--- a/src/fs/fs_download.c
+++ b/src/fs/fs_download.c
@@ -33,7 +33,7 @@
 #include "fs.h"
 #include "fs_tree.h"
 
-#define DEBUG_DOWNLOAD GNUNET_YES
+#define DEBUG_DOWNLOAD GNUNET_NO
 
 /**
  * Determine if the given download (options and meta data) should cause
@@ -330,10 +330,14 @@ 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,
@@ -364,6 +368,7 @@ schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
          return;
        }
     }
+ do_download:
   if (fh != NULL)
     GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (fh));
   if (depth < dc->treedepth)
@@ -915,11 +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,
@@ -1647,7 +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;