* advertising or publicity pertaining to the Software or any
* derivatives without specific, written prior permission.
*/
+#include <config.h>
#include <sys/types.h>
#include "flow.h"
#include <inttypes.h>
#include <netinet/in.h>
#include <string.h>
-#include "buffer.h"
#include "hash.h"
+#include "ofpbuf.h"
#include "openflow.h"
#include "packets.h"
#include "vlog.h"
#define THIS_MODULE VLM_flow
-void
-flow_extract(struct buffer *packet, uint16_t in_port, struct flow *flow)
+static struct ip_header *
+pull_ip(struct ofpbuf *packet)
{
- struct buffer b = *packet;
+ if (packet->size >= IP_HEADER_LEN) {
+ struct ip_header *ip = packet->data;
+ int ip_len = IP_IHL(ip->ip_ihl_ver) * 4;
+ if (ip_len >= IP_HEADER_LEN && packet->size >= ip_len) {
+ return ofpbuf_pull(packet, ip_len);
+ }
+ }
+ return NULL;
+}
+
+static struct tcp_header *
+pull_tcp(struct ofpbuf *packet)
+{
+ if (packet->size >= TCP_HEADER_LEN) {
+ struct tcp_header *tcp = packet->data;
+ int tcp_len = TCP_OFFSET(tcp->tcp_ctl) * 4;
+ if (tcp_len >= TCP_HEADER_LEN && packet->size >= tcp_len) {
+ return ofpbuf_pull(packet, tcp_len);
+ }
+ }
+ return NULL;
+}
+
+static struct udp_header *
+pull_udp(struct ofpbuf *packet)
+{
+ return ofpbuf_try_pull(packet, UDP_HEADER_LEN);
+}
+
+static struct eth_header *
+pull_eth(struct ofpbuf *packet)
+{
+ return ofpbuf_try_pull(packet, ETH_HEADER_LEN);
+}
+
+static struct vlan_header *
+pull_vlan(struct ofpbuf *packet)
+{
+ return ofpbuf_try_pull(packet, VLAN_HEADER_LEN);
+}
+
+/* Returns 1 if 'packet' is an IP fragment, 0 otherwise. */
+int
+flow_extract(struct ofpbuf *packet, uint16_t in_port, struct flow *flow)
+{
+ struct ofpbuf b = *packet;
struct eth_header *eth;
+ int retval = 0;
if (b.size < ETH_TOTAL_MIN) {
- VLOG_WARN("packet length %zu less than minimum size %d",
- b.size, ETH_TOTAL_MIN);
+ /* This message is not too useful since there are various ways that we
+ * can end up with runt frames, e.g. frames that only ever passed
+ * through virtual network devices and never touched a physical
+ * Ethernet. */
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 60);
+ VLOG_DBG_RL(&rl, "packet length %zu less than minimum size %d",
+ b.size, ETH_TOTAL_MIN);
}
memset(flow, 0, sizeof *flow);
+ flow->dl_vlan = htons(OFP_VLAN_NONE);
flow->in_port = htons(in_port);
packet->l2 = b.data;
packet->l3 = NULL;
packet->l4 = NULL;
+ packet->l7 = NULL;
- eth = buffer_at(&b, 0, sizeof *eth);
+ eth = pull_eth(&b);
if (eth) {
- buffer_pull(&b, ETH_HEADER_LEN);
if (ntohs(eth->eth_type) >= OFP_DL_TYPE_ETH2_CUTOFF) {
/* This is an Ethernet II frame */
flow->dl_type = eth->eth_type;
} else {
/* This is an 802.2 frame */
- struct llc_snap_header *h = buffer_at(&b, 0, sizeof *h);
+ struct llc_snap_header *h = ofpbuf_at(&b, 0, sizeof *h);
if (h == NULL) {
- return;
+ return 0;
}
if (h->llc.llc_dsap == LLC_DSAP_SNAP
&& h->llc.llc_ssap == LLC_SSAP_SNAP
&& !memcmp(h->snap.snap_org, SNAP_ORG_ETHERNET,
sizeof h->snap.snap_org)) {
flow->dl_type = h->snap.snap_type;
- buffer_pull(&b, sizeof *h);
+ ofpbuf_pull(&b, sizeof *h);
} else {
- flow->dl_type = OFP_DL_TYPE_NOT_ETH_TYPE;
- buffer_pull(&b, sizeof(struct llc_header));
+ flow->dl_type = htons(OFP_DL_TYPE_NOT_ETH_TYPE);
+ ofpbuf_pull(&b, sizeof(struct llc_header));
}
}
/* Check for a VLAN tag */
- if (flow->dl_type != htons(ETH_TYPE_VLAN)) {
- flow->dl_vlan = htons(OFP_VLAN_NONE);
- } else {
- struct vlan_header *vh = buffer_at(&b, 0, sizeof *vh);
- flow->dl_type = vh->vlan_next_type;
- flow->dl_vlan = vh->vlan_tci & htons(VLAN_VID);
- buffer_pull(&b, sizeof *vh);
+ if (flow->dl_type == htons(ETH_TYPE_VLAN)) {
+ struct vlan_header *vh = pull_vlan(&b);
+ if (vh) {
+ flow->dl_type = vh->vlan_next_type;
+ flow->dl_vlan = vh->vlan_tci & htons(VLAN_VID_MASK);
+ }
}
memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
packet->l3 = b.data;
if (flow->dl_type == htons(ETH_TYPE_IP)) {
- const struct ip_header *nh = buffer_at(&b, 0, sizeof *nh);
+ const struct ip_header *nh = pull_ip(&b);
if (nh) {
- int ip_len = IP_IHL(nh->ip_ihl_ver) * 4;
- if (ip_len < IP_HEADER_LEN) {
- return;
- }
-
flow->nw_src = nh->ip_src;
flow->nw_dst = nh->ip_dst;
flow->nw_proto = nh->ip_proto;
- if (flow->nw_proto == IP_TYPE_TCP
- || flow->nw_proto == IP_TYPE_UDP) {
- const struct udp_header *th;
- th = packet->l4 = buffer_at(&b, ip_len, sizeof *th);
- if (th) {
- flow->tp_src = th->udp_src;
- flow->tp_dst = th->udp_dst;
- } else {
- /* Avoid tricking other code into thinking that this
- * packet has an L4 header. */
- flow->nw_proto = 0;
+ packet->l4 = b.data;
+ if (!IP_IS_FRAGMENT(nh->ip_frag_off)) {
+ if (flow->nw_proto == IP_TYPE_TCP) {
+ const struct tcp_header *tcp = pull_tcp(&b);
+ if (tcp) {
+ flow->tp_src = tcp->tcp_src;
+ flow->tp_dst = tcp->tcp_dst;
+ packet->l7 = b.data;
+ } else {
+ /* Avoid tricking other code into thinking that
+ * this packet has an L4 header. */
+ flow->nw_proto = 0;
+ }
+ } else if (flow->nw_proto == IP_TYPE_UDP) {
+ const struct udp_header *udp = pull_udp(&b);
+ if (udp) {
+ flow->tp_src = udp->udp_src;
+ flow->tp_dst = udp->udp_dst;
+ packet->l7 = b.data;
+ } else {
+ /* Avoid tricking other code into thinking that
+ * this packet has an L4 header. */
+ flow->nw_proto = 0;
+ }
}
+ } else {
+ retval = 1;
}
}
}
}
+ return retval;
}
void
git://git.onelab.eu / sliver-openvswitch.git / blobdiff