FTP: allow garbage instead of "ls -l" permissions listing.

Some broken servers send garbage in that place,
and we still can parse the rest of the line.

BUG=none


Review URL: https://chromiumcodereview.appspot.com/11475039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@172149 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 17 insertions, 46 deletions

diff --git a/net/ftp/ftp_directory_listing_parser_ls.cc b/net/ftp/ftp_directory_listing_parser_ls.cc
index 1257d5a..9657ccd 100644
--- a/net/ftp/ftp_directory_listing_parser_ls.cc
+++ b/net/ftp/ftp_directory_listing_parser_ls.cc
@@ -16,42 +16,6 @@
 
 namespace {
 
-bool LooksLikeUnixPermission(const string16& text) {
-  if (text.length() != 3)
-    return false;
-
-  // Meaning of the flags:
-  // r - file is readable
-  // w - file is writable
-  // x - file is executable
-  // s, S or l - setuid/setgid bit set
-  // t or T - "sticky" bit set
-  return ((text[0] == 'r' || text[0] == '-') &&
-          (text[1] == 'w' || text[1] == '-') &&
-          (text[2] == 'x' || text[2] == '-' ||
-           text[2] == 's' || text[2] == 'S' || text[2] == 'l' ||
-           text[2] == 't' || text[2] == 'T'));
-}
-
-bool LooksLikeUnixPermissionsListing(const string16& text) {
-  if (text.length() < 7)
-    return false;
-
-  // Do not check the first character (entry type). There are many weird
-  // servers that use special file types (for example Plan9 and append-only
-  // files). Fortunately, the rest of the permission listing is more consistent.
-
-  // Do not check the rest of the string. Some servers fail to properly
-  // separate this column from the next column (number of links), resulting
-  // in additional characters at the end. Also, sometimes there is a "+"
-  // sign at the end indicating the file has ACLs set.
-
-  // In fact, we don't even expect three "rwx" triplets of permission
-  // listing, as some FTP servers like Hylafax only send two.
-  return (LooksLikeUnixPermission(text.substr(1, 3)) &&
-          LooksLikeUnixPermission(text.substr(4, 3)));
-}
-
 bool TwoColumnDateListingToTime(const string16& date,
                                 const string16& time,
                                 base::Time* result) {
@@ -209,11 +173,12 @@ bool ParseFtpDirectoryListingLs(
       return false;
     }
 
-    if (!LooksLikeUnixPermissionsListing(columns[0]))
-      return false;
-    if (columns[0][0] == 'l') {
+    // Do not check "validity" of the permission listing. It's quirky,
+    // and some servers send garbage here while other parts of the line are OK.
+
+    if (!columns[0].empty() && columns[0][0] == 'l') {
       entry.type = FtpDirectoryListingEntry::SYMLINK;
-    } else if (columns[0][0] == 'd') {
+    } else if (!columns[0].empty() && columns[0][0] == 'd') {
       entry.type = FtpDirectoryListingEntry::DIRECTORY;
     } else {
       entry.type = FtpDirectoryListingEntry::FILE;
diff --git a/net/ftp/ftp_directory_listing_parser_ls_unittest.cc b/net/ftp/ftp_directory_listing_parser_ls_unittest.cc
index 456fb6e..92431bc 100644
--- a/net/ftp/ftp_directory_listing_parser_ls_unittest.cc
+++ b/net/ftp/ftp_directory_listing_parser_ls_unittest.cc
@@ -136,6 +136,18 @@ TEST_F(FtpDirectoryListingParserLsTest, Good) {
       "Shortcut to incoming.lnk -> /t11/member/incoming",
       FtpDirectoryListingEntry::SYMLINK, "Shortcut to incoming.lnk", -1,
       2007, 2, 8, 0, 0 },
+
+    // Garbage in permissions (with no effect on other bits).
+    // Also test multiple "columns" resulting from the garbage.
+    { "garbage    1 ftp      ftp           528 Nov 01  2007 README",
+      FtpDirectoryListingEntry::FILE, "README", 528,
+      2007, 11, 1, 0, 0 },
+    { "gar bage    1 ftp      ftp           528 Nov 01  2007 README",
+      FtpDirectoryListingEntry::FILE, "README", 528,
+      2007, 11, 1, 0, 0 },
+    { "g a r b a g e    1 ftp      ftp           528 Nov 01  2007 README",
+      FtpDirectoryListingEntry::FILE, "README", 528,
+      2007, 11, 1, 0, 0 },
   };
   for (size_t i = 0; i < arraysize(good_cases); i++) {
     SCOPED_TRACE(base::StringPrintf("Test[%" PRIuS "]: %s", i,
@@ -182,17 +194,11 @@ TEST_F(FtpDirectoryListingParserLsTest, Bad) {
     " foo",
     "garbage",
     "-rw-r--r-- ftp ftp",
-    "-rw-rgbr-- ftp ftp 528 Nov 01 2007 README",
-    "qrwwr--r-- ftp ftp 528 Nov 01 2007 README",
     "-rw-r--r-- ftp ftp 528 Foo 01 2007 README",
     "-rw-r--r-- 1 ftp ftp",
-    "-rw-rgbr-- 1 ftp ftp 528 Nov 01 2007 README",
-    "qrwwr--r-- 1 ftp ftp 528 Nov 01 2007 README",
     "-rw-r--r-- 1 ftp ftp 528 Foo 01 2007 README",
     "drwxrwxrwx   1 owner    group               1024 Sep 13  0:3 audio",
 
-    "-qqqqqqqqq+  2 sys          512 Mar 27  2009 pub",
-
     // Invalid month value (30).
     "drwxrwxrwx 2 root root  4096 2012-30-07 00:31 notas_servico",
   };