(trunk, libT) #5517 when parsing a torrent's metainfo's path list, allow empty components because some .torrent files innocently have them. Update unit tests.

libtransmission/metainfo-test.c

@@ -7,12 +7,14 @@
  * $Id$
  */
 
-#include "transmission.h"
-
 #include "libtransmission-test.h"
 
+#include "transmission.h"
+
+#include <errno.h>
+
 static int
-test1 (void)
+test_magnet_link (void)
 {
   tr_info inf;
   tr_ctor * ctor;
@@ -43,4 +45,64 @@ test1 (void)
   return 0;
 }
 
-MAIN_SINGLE_TEST (test1)
+#define BEFORE_PATH "d10:created by25:Transmission/2.82 (14160)13:creation datei1402280218e8:encoding5:UTF-84:infod5:filesld6:lengthi2e4:pathl"
+#define AFTER_PATH "eed6:lengthi2e4:pathl5:b.txteee4:name3:foo12:piece lengthi32768e6:pieces20:ÞÉ`âM‘‹Šs¡Å;˺¬.åÂà7:privatei0eee"
+
+static int
+test_metainfo (void)
+{
+  size_t i;
+  const struct {
+    int expected_benc_err;
+    int expected_parse_result;
+    const void * benc;
+  } metainfo[] = {
+    { 0,      TR_PARSE_OK,  BEFORE_PATH "5:a.txt"     AFTER_PATH },
+
+    /* allow empty components, but not =all= empty components, see bug #5517 */
+    { 0,      TR_PARSE_OK,  BEFORE_PATH "0:5:a.txt"   AFTER_PATH },
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "0:0:"        AFTER_PATH },
+
+    /* don't allow path components in a filename */
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "7:a/a.txt"   AFTER_PATH },
+
+    /* fail on "." components */
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "1:.5:a.txt"  AFTER_PATH },
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "5:a.txt1:."  AFTER_PATH },
+
+    /* fail on ".." components */
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "2:..5:a.txt" AFTER_PATH },
+    { 0,      TR_PARSE_ERR, BEFORE_PATH "5:a.txt2:.." AFTER_PATH },
+
+    /* fail on empty string */
+    { EILSEQ, TR_PARSE_ERR, "" }
+  };
+
+  tr_logSetLevel(0); /* yes, we already know these will generate errors, thank you... */
+
+
+  for (i=0; i<(sizeof(metainfo) / sizeof(metainfo[0])); i++)
+    {
+      tr_ctor * ctor = tr_ctorNew (NULL);
+      const int err = tr_ctorSetMetainfo (ctor, metainfo[i].benc, strlen(metainfo[i].benc));
+      check_int_eq (metainfo[i].expected_benc_err, err);
+      if (!err)
+        {
+          const tr_parse_result parse_result = tr_torrentParse (ctor, NULL);
+          check_int_eq (metainfo[i].expected_parse_result, parse_result);
+        }
+      tr_ctorFree (ctor);
+    }
+
+  return 0;
+}
+    
+int
+main (void)
+{
+  const testFunc tests[] = { test_magnet_link,
+                             test_metainfo };
+
+  return runTests (tests, NUM_TESTS (tests));
+}
+

libtransmission/metainfo.c

@@ -76,7 +76,6 @@ static bool
 path_component_is_suspicious (const char * component)
 {
   return (component == NULL)
-      || (*component == '\0')
       || (strpbrk (component, PATH_DELIMITER_CHARS) != NULL)
       || (strcmp (component, ".") == 0)
       || (strcmp (component, "..") == 0);
@@ -86,6 +85,7 @@ static bool
 getfile (char ** setme, const char * root, tr_variant * path, struct evbuffer * buf)
 {
   bool success = false;
+  size_t root_len = 0;
 
   *setme = NULL;
 
@@ -99,7 +99,8 @@ getfile (char ** setme, const char * root, tr_variant * path, struct evbuffer *
 
       success = true;
       evbuffer_drain (buf, evbuffer_get_length (buf));
-      evbuffer_add (buf, root, strlen (root));
+      root_len = strlen (root);
+      evbuffer_add (buf, root, root_len);
 
       for (i=0; i<n; i++)
         {
@@ -113,11 +114,19 @@ getfile (char ** setme, const char * root, tr_variant * path, struct evbuffer *
               break;
             }
 
+          if (!*str)
+            continue;
+
           evbuffer_add (buf, TR_PATH_DELIMITER_STR, 1);
           evbuffer_add (buf, str, len);
         }
     }
 
+  if (success && (evbuffer_get_length (buf) <= root_len))
+    {
+      success = false;
+    }
+
   if (success)
     {
       *setme = tr_utf8clean ((char*)evbuffer_pullup (buf, -1), evbuffer_get_length (buf));

libtransmission/variant-benc.c

@@ -248,8 +248,8 @@ tr_variantParseBenc (const void    * buf_in,
         break;
     }
 
-  if (!err)
-    err = !top->type || !tr_ptrArrayEmpty(&stack);
+  if (!err && (!top->type || !tr_ptrArrayEmpty(&stack)))
+    err = EILSEQ;
 
   if (!err && setme_end)
     *setme_end = (const char*) buf;