- Added support for passive mode FTP by aliasing 227 replies.

  It does mean that it is now possible to run passive-mode FTP
  server behind NAT.

- SECURITY: FTP aliasing engine now ensures that:
  o the segment preceding a PORT/227 segment terminates with a \r\n;
  o the IP address in the PORT/227 matches the source IP address of
    the packet;
  o the port number in the PORT command or 277 reply is greater than
    or equal to 1024.

Submitted by:	Erik Salander <erik@whistle.com>
Reviewed by:	ru

1 files changed, 19 insertions, 0 deletions

diff --git a/lib/libalias/alias_db.c b/lib/libalias/alias_db.c
index e7a8901..211a7c2 100644
--- a/lib/libalias/alias_db.c
+++ b/lib/libalias/alias_db.c
@@ -274,6 +274,7 @@ struct alias_link                /* Main data structure */
 #define LINK_PERMANENT             0x04
 #define LINK_PARTIALLY_SPECIFIED   0x03 /* logical-or of first two bits */
 #define LINK_UNFIREWALLED          0x08
+#define LINK_LAST_LINE_CRLF_TERMED 0x10
 
     int timestamp;               /* Time link was last accessed         */
     int expire_time;             /* Expire time for link                */
@@ -1596,6 +1597,7 @@ FindAliasAddress(struct in_addr original_addr)
     GetOriginalPort(), GetAliasPort()
     SetAckModified(), GetAckModified()
     GetDeltaAckIn(), GetDeltaSeqOut(), AddSeq()
+    SetLastLineCrlfTermed(), GetLastLineCrlfTermed()
 */
 
 
@@ -1961,6 +1963,23 @@ ClearCheckNewLink(void)
     newDefaultLink = 0;
 }
 
+void
+SetLastLineCrlfTermed(struct alias_link *link, int yes)
+{
+
+    if (yes)
+	link->flags |= LINK_LAST_LINE_CRLF_TERMED;
+    else
+	link->flags &= ~LINK_LAST_LINE_CRLF_TERMED;
+}
+
+int
+GetLastLineCrlfTermed(struct alias_link *link)
+{
+
+    return (link->flags & LINK_LAST_LINE_CRLF_TERMED);
+}
+
 
 /* Miscellaneous Functions