/*
- * Copyright (c) 2009, 2010, 2012, 2013 Nicira, Inc.
+ * Copyright (c) 2009, 2010, 2012, 2013, 2014 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
}
static struct tcp_stream *
-tcp_stream_lookup(struct tcp_reader *r, const struct flow *flow)
+tcp_stream_lookup(struct tcp_reader *r,
+ const struct tcp_key *key, uint32_t hash)
{
struct tcp_stream *stream;
- struct tcp_key key;
- uint32_t hash;
-
- memset(&key, 0, sizeof key);
- key.nw_src = flow->nw_src;
- key.nw_dst = flow->nw_dst;
- key.tp_src = flow->tp_src;
- key.tp_dst = flow->tp_dst;
- hash = hash_bytes(&key, sizeof key, 0);
HMAP_FOR_EACH_WITH_HASH (stream, hmap_node, hash, &r->streams) {
- if (!memcmp(&stream->key, &key, sizeof key)) {
+ if (!memcmp(&stream->key, key, sizeof *key)) {
return stream;
}
}
+ return NULL;
+}
+
+static struct tcp_stream *
+tcp_stream_new(struct tcp_reader *r, const struct tcp_key *key, uint32_t hash)
+{
+ struct tcp_stream *stream;
stream = xmalloc(sizeof *stream);
hmap_insert(&r->streams, &stream->hmap_node, hash);
- memcpy(&stream->key, &key, sizeof key);
+ memcpy(&stream->key, key, sizeof *key);
stream->seq_no = 0;
ofpbuf_init(&stream->payload, 2048);
return stream;
struct tcp_stream *stream;
struct tcp_header *tcp;
struct ofpbuf *payload;
+ unsigned int l7_length;
+ struct tcp_key key;
+ uint32_t hash;
uint32_t seq;
uint8_t flags;
+ const char *l7 = ofpbuf_get_tcp_payload(packet);
if (flow->dl_type != htons(ETH_TYPE_IP)
|| flow->nw_proto != IPPROTO_TCP
- || !packet->l7) {
+ || !l7) {
return NULL;
}
-
- stream = tcp_stream_lookup(r, flow);
- payload = &stream->payload;
-
- tcp = packet->l4;
+ tcp = ofpbuf_get_l4(packet);
flags = TCP_FLAGS(tcp->tcp_ctl);
+ l7_length = (char *) ofpbuf_tail(packet) - l7;
seq = ntohl(get_16aligned_be32(&tcp->tcp_seq));
- if (flags & TCP_SYN) {
+
+ /* Construct key. */
+ memset(&key, 0, sizeof key);
+ key.nw_src = flow->nw_src;
+ key.nw_dst = flow->nw_dst;
+ key.tp_src = flow->tp_src;
+ key.tp_dst = flow->tp_dst;
+ hash = hash_bytes(&key, sizeof key, 0);
+
+ /* Find existing stream or start a new one for a SYN or if there's data. */
+ stream = tcp_stream_lookup(r, &key, hash);
+ if (!stream) {
+ if (flags & TCP_SYN || l7_length) {
+ stream = tcp_stream_new(r, &key, hash);
+ stream->seq_no = flags & TCP_SYN ? seq + 1 : seq;
+ } else {
+ return NULL;
+ }
+ }
+
+ payload = &stream->payload;
+ if (flags & TCP_SYN || !stream->seq_no) {
ofpbuf_clear(payload);
stream->seq_no = seq + 1;
return NULL;
tcp_stream_destroy(r, stream);
return NULL;
} else if (seq == stream->seq_no) {
- size_t length;
-
/* Shift all of the existing payload to the very beginning of the
* allocated space, so that we reuse allocated space instead of
* continually expanding it. */
ofpbuf_shift(payload, (char *) payload->base - (char *) payload->data);
- length = (char *) ofpbuf_end(packet) - (char *) packet->l7;
- ofpbuf_put(payload, packet->l7, length);
- stream->seq_no += length;
+ ofpbuf_put(payload, l7, l7_length);
+ stream->seq_no += l7_length;
return payload;
} else {
return NULL;