MEDIUM: netscaler: add support for standard NetScaler CIP protocol
It looks like two version of the protocol exist as reported by
Andreas Mahnke. This patch add support for both legacy and standard CIP
protocol according to NetScaler specifications.
diff --git a/src/connection.c b/src/connection.c
index 58bf4a5..0f8acb0 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -678,14 +678,8 @@
}
/* This handshake handler waits a NetScaler Client IP insertion header
- * at the beginning of the raw data stream. The header looks like this:
- *
- * 4 bytes: CIP magic number
- * 4 bytes: Header length
- * 20+ bytes: Header of the last IP packet sent by the client during
- * TCP handshake.
- * 20+ bytes: Header of the last TCP packet sent by the client during
- * TCP handshake.
+ * at the beginning of the raw data stream. The header format is
+ * described in doc/netscaler-client-ip-insertion-protocol.txt
*
* This line MUST be at the beginning of the buffer and MUST NOT be
* fragmented.
@@ -735,25 +729,39 @@
}
/* Fail if buffer length is not large enough to contain
- * CIP magic, CIP length */
- if (trash.len < 8)
+ * CIP magic, header length or
+ * CIP magic, CIP length, CIP type, header length */
+ if (trash.len < 12)
goto missing;
line = trash.str;
- hdr_len = ntohl(*(uint32_t *)(line+4));
/* Decode a possible NetScaler Client IP request, fail early if
* it does not match */
if (ntohl(*(uint32_t *)line) != objt_listener(conn->target)->bind_conf->ns_cip_magic)
goto bad_magic;
+ /* Legacy CIP protocol */
+ if ((trash.str[8] & 0xD0) == 0x40) {
+ hdr_len = ntohl(*(uint32_t *)(line+4));
+ line += 8;
+ }
+ /* Standard CIP protocol */
+ else if (trash.str[8] == 0x00) {
+ hdr_len = ntohs(*(uint32_t *)(line+10));
+ line += 12;
+ }
+ /* Unknown CIP protocol */
+ else {
+ conn->err_code = CO_ER_CIP_BAD_PROTO;
+ goto fail;
+ }
+
/* Fail if buffer length is not large enough to contain
- * CIP magic, CIP length, minimal IP header */
- if (trash.len < 28)
+ * a minimal IP header */
+ if (trash.len < 20)
goto missing;
- line += 8;
-
/* Get IP version from the first four bits */
ip_v = (*line & 0xf0) >> 4;