#include <linux/ip.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
+#include <linux/llc.h>
#include <linux/module.h>
#include <linux/tcp.h>
#include <linux/udp.h>
+#include <linux/icmp.h>
#include <linux/in.h>
#include <linux/rcupdate.h>
#include <net/ip.h>
-#include "openflow.h"
+#include "openflow/openflow.h"
#include "compat.h"
-#include "snap.h"
struct kmem_cache *flow_cache;
/* Internal function used to compare fields in flow. */
static inline
int flow_fields_match(const struct sw_flow_key *a, const struct sw_flow_key *b,
- uint16_t w)
+ uint32_t w, uint32_t src_mask, uint32_t dst_mask)
{
return ((w & OFPFW_IN_PORT || a->in_port == b->in_port)
&& (w & OFPFW_DL_VLAN || a->dl_vlan == b->dl_vlan)
&& (w & OFPFW_DL_SRC || !memcmp(a->dl_src, b->dl_src, ETH_ALEN))
&& (w & OFPFW_DL_DST || !memcmp(a->dl_dst, b->dl_dst, ETH_ALEN))
&& (w & OFPFW_DL_TYPE || a->dl_type == b->dl_type)
- && (w & OFPFW_NW_SRC || a->nw_src == b->nw_src)
- && (w & OFPFW_NW_DST || a->nw_dst == b->nw_dst)
+ && !((a->nw_src ^ b->nw_src) & src_mask)
+ && !((a->nw_dst ^ b->nw_dst) & dst_mask)
&& (w & OFPFW_NW_PROTO || a->nw_proto == b->nw_proto)
&& (w & OFPFW_TP_SRC || a->tp_src == b->tp_src)
&& (w & OFPFW_TP_DST || a->tp_dst == b->tp_dst));
}
/* Returns nonzero if 'a' and 'b' match, that is, if their fields are equal
- * modulo wildcards, zero otherwise. */
-int flow_matches(const struct sw_flow_key *a, const struct sw_flow_key *b)
+ * modulo wildcards in 'b', zero otherwise. */
+int flow_matches_1wild(const struct sw_flow_key *a,
+ const struct sw_flow_key *b)
{
- return flow_fields_match(a, b, (a->wildcards | b->wildcards));
+ return flow_fields_match(a, b, b->wildcards,
+ b->nw_src_mask, b->nw_dst_mask);
}
-EXPORT_SYMBOL(flow_matches);
+EXPORT_SYMBOL(flow_matches_1wild);
-/* Returns nonzero if 't' (the table entry's key) and 'd' (the key
- * describing the deletion) match, that is, if their fields are
+/* Returns nonzero if 'a' and 'b' match, that is, if their fields are equal
+ * modulo wildcards in 'a' or 'b', zero otherwise. */
+int flow_matches_2wild(const struct sw_flow_key *a,
+ const struct sw_flow_key *b)
+{
+ return flow_fields_match(a, b,
+ a->wildcards | b->wildcards,
+ a->nw_src_mask & b->nw_src_mask,
+ a->nw_dst_mask & b->nw_dst_mask);
+}
+EXPORT_SYMBOL(flow_matches_2wild);
+
+/* Returns nonzero if 't' (the table entry's key) and 'd' (the key
+ * describing the match) match, that is, if their fields are
* equal modulo wildcards, zero otherwise. If 'strict' is nonzero, the
* wildcards must match in both 't_key' and 'd_key'. Note that the
* table's wildcards are ignored unless 'strict' is set. */
-int flow_del_matches(const struct sw_flow_key *t, const struct sw_flow_key *d, int strict)
+int flow_matches_desc(const struct sw_flow_key *t, const struct sw_flow_key *d,
+ int strict)
{
- if (strict && (t->wildcards != d->wildcards))
+ if (strict && d->wildcards != t->wildcards)
return 0;
+ return flow_matches_1wild(t, d);
+}
+EXPORT_SYMBOL(flow_matches_desc);
- return flow_fields_match(t, d, d->wildcards);
+static uint32_t make_nw_mask(int n_wild_bits)
+{
+ n_wild_bits &= (1u << OFPFW_NW_SRC_BITS) - 1;
+ return n_wild_bits < 32 ? htonl(~((1u << n_wild_bits) - 1)) : 0;
}
-EXPORT_SYMBOL(flow_del_matches);
void flow_extract_match(struct sw_flow_key* to, const struct ofp_match* from)
{
- to->wildcards = ntohs(from->wildcards) & OFPFW_ALL;
- memset(to->pad, '\0', sizeof(to->pad));
+ to->wildcards = ntohl(from->wildcards) & OFPFW_ALL;
+ to->pad = 0;
to->in_port = from->in_port;
to->dl_vlan = from->dl_vlan;
memcpy(to->dl_src, from->dl_src, ETH_ALEN);
to->tp_src = to->tp_dst = 0;
#define OFPFW_TP (OFPFW_TP_SRC | OFPFW_TP_DST)
-#define OFPFW_NW (OFPFW_NW_SRC | OFPFW_NW_DST | OFPFW_NW_PROTO)
+#define OFPFW_NW (OFPFW_NW_SRC_MASK | OFPFW_NW_DST_MASK | OFPFW_NW_PROTO)
if (to->wildcards & OFPFW_DL_TYPE) {
/* Can't sensibly match on network or transport headers if the
* data link type is unknown. */
* network protocol is unknown. */
to->wildcards |= OFPFW_TP;
} else if (from->nw_proto == IPPROTO_TCP
- || from->nw_proto == IPPROTO_UDP) {
+ || from->nw_proto == IPPROTO_UDP
+ || from->nw_proto == IPPROTO_ICMP) {
to->tp_src = from->tp_src;
to->tp_dst = from->tp_dst;
} else {
* instead of falling into table-linear. */
to->wildcards &= ~(OFPFW_NW | OFPFW_TP);
}
+
+ /* We set these late because code above adjusts to->wildcards. */
+ to->nw_src_mask = make_nw_mask(to->wildcards >> OFPFW_NW_SRC_SHIFT);
+ to->nw_dst_mask = make_nw_mask(to->wildcards >> OFPFW_NW_DST_SHIFT);
}
void flow_fill_match(struct ofp_match* to, const struct sw_flow_key* from)
{
- to->wildcards = htons(from->wildcards);
+ to->wildcards = htonl(from->wildcards);
to->in_port = from->in_port;
to->dl_vlan = from->dl_vlan;
memcpy(to->dl_src, from->dl_src, ETH_ALEN);
memcpy(to->dl_dst, from->dl_dst, ETH_ALEN);
to->dl_type = from->dl_type;
- to->nw_src = from->nw_src;
- to->nw_dst = from->nw_dst;
+ to->nw_src = from->nw_src;
+ to->nw_dst = from->nw_dst;
to->nw_proto = from->nw_proto;
- to->tp_src = from->tp_src;
- to->tp_dst = from->tp_dst;
- memset(to->pad, '\0', sizeof(to->pad));
+ to->tp_src = from->tp_src;
+ to->tp_dst = from->tp_dst;
+ to->pad = 0;
}
int flow_timeout(struct sw_flow *flow)
}
EXPORT_SYMBOL(flow_timeout);
-/* Allocates and returns a new flow with 'n_actions' action, using allocation
- * flags 'flags'. Returns the new flow or a null pointer on failure. */
-struct sw_flow *flow_alloc(int n_actions, gfp_t flags)
+/* Returns nonzero if 'flow' contains an output action to 'out_port' or
+ * has the value OFPP_NONE. 'out_port' is in network-byte order. */
+int flow_has_out_port(struct sw_flow *flow, uint16_t out_port)
+{
+ struct sw_flow_actions *sf_acts;
+ size_t actions_len;
+ uint8_t *p;
+
+ if (out_port == htons(OFPP_NONE))
+ return 1;
+
+ sf_acts = rcu_dereference(flow->sf_acts);
+
+ actions_len = sf_acts->actions_len;
+ p = (uint8_t *)sf_acts->actions;
+
+ while (actions_len > 0) {
+ struct ofp_action_header *ah = (struct ofp_action_header *)p;
+ size_t len = ntohs(ah->len);
+
+ if (ah->type == htons(OFPAT_OUTPUT)) {
+ struct ofp_action_output *oa = (struct ofp_action_output *)p;
+ if (oa->port == out_port)
+ return 1;
+ }
+
+ p += len;
+ actions_len -= len;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(flow_has_out_port);
+
+/* Allocates and returns a new flow with room for 'actions_len' actions,
+ * using allocation flags 'flags'. Returns the new flow or a null pointer
+ * on failure. */
+struct sw_flow *flow_alloc(size_t actions_len, gfp_t flags)
{
+ struct sw_flow_actions *sfa;
+ size_t size = sizeof *sfa + actions_len;
struct sw_flow *flow = kmem_cache_alloc(flow_cache, flags);
if (unlikely(!flow))
return NULL;
- flow->n_actions = n_actions;
- flow->actions = kmalloc(n_actions * sizeof *flow->actions,
- flags);
- if (unlikely(!flow->actions) && n_actions > 0) {
+ sfa = kmalloc(size, flags);
+ if (unlikely(!sfa)) {
kmem_cache_free(flow_cache, flow);
return NULL;
}
+ sfa->actions_len = actions_len;
+ flow->sf_acts = sfa;
+
return flow;
}
{
if (unlikely(!flow))
return;
- kfree(flow->actions);
+ kfree(flow->sf_acts);
kmem_cache_free(flow_cache, flow);
}
EXPORT_SYMBOL(flow_free);
/* RCU callback used by flow_deferred_free. */
-static void rcu_callback(struct rcu_head *rcu)
+static void rcu_free_flow_callback(struct rcu_head *rcu)
{
struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
flow_free(flow);
* The caller must hold rcu_read_lock for this to be sensible. */
void flow_deferred_free(struct sw_flow *flow)
{
- call_rcu(&flow->rcu, rcu_callback);
+ call_rcu(&flow->rcu, rcu_free_flow_callback);
}
EXPORT_SYMBOL(flow_deferred_free);
+/* RCU callback used by flow_deferred_free_acts. */
+static void rcu_free_acts_callback(struct rcu_head *rcu)
+{
+ struct sw_flow_actions *sf_acts = container_of(rcu,
+ struct sw_flow_actions, rcu);
+ kfree(sf_acts);
+}
+
+/* Schedules 'sf_acts' to be freed after the next RCU grace period.
+ * The caller must hold rcu_read_lock for this to be sensible. */
+void flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
+{
+ call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
+}
+EXPORT_SYMBOL(flow_deferred_free_acts);
+
+/* Copies 'actions' into a newly allocated structure for use by 'flow'
+ * and safely frees the structure that defined the previous actions. */
+void flow_replace_acts(struct sw_flow *flow,
+ const struct ofp_action_header *actions, size_t actions_len)
+{
+ struct sw_flow_actions *sfa;
+ struct sw_flow_actions *orig_sfa = flow->sf_acts;
+ size_t size = sizeof *sfa + actions_len;
+
+ sfa = kmalloc(size, GFP_ATOMIC);
+ if (unlikely(!sfa))
+ return;
+
+ sfa->actions_len = actions_len;
+ memcpy(sfa->actions, actions, actions_len);
+
+ rcu_assign_pointer(flow->sf_acts, sfa);
+ flow_deferred_free_acts(orig_sfa);
+
+ return;
+}
+EXPORT_SYMBOL(flow_replace_acts);
+
/* Prints a representation of 'key' to the kernel log. */
void print_flow(const struct sw_flow_key *key)
{
- printk("wild%04x port%04x:vlan%04x mac%02x:%02x:%02x:%02x:%02x:%02x"
+ printk("wild%08x port%04x:vlan%04x mac%02x:%02x:%02x:%02x:%02x:%02x"
"->%02x:%02x:%02x:%02x:%02x:%02x "
"proto%04x ip%u.%u.%u.%u->%u.%u.%u.%u port%d->%d\n",
key->wildcards, ntohs(key->in_port), ntohs(key->dl_vlan),
}
EXPORT_SYMBOL(print_flow);
+#define SNAP_OUI_LEN 3
+
+struct eth_snap_hdr
+{
+ struct ethhdr eth;
+ uint8_t dsap; /* Always 0xAA */
+ uint8_t ssap; /* Always 0xAA */
+ uint8_t ctrl;
+ uint8_t oui[SNAP_OUI_LEN];
+ uint16_t ethertype;
+} __attribute__ ((packed));
+
+static int is_snap(const struct eth_snap_hdr *esh)
+{
+ return (esh->dsap == LLC_SAP_SNAP
+ && esh->ssap == LLC_SAP_SNAP
+ && !memcmp(esh->oui, "\0\0\0", 3));
+}
+
+static int iphdr_ok(struct sk_buff *skb)
+{
+ int nh_ofs = skb_network_offset(skb);
+ if (skb->len >= nh_ofs + sizeof(struct iphdr)) {
+ int ip_len = ip_hdrlen(skb);
+ return (ip_len >= sizeof(struct iphdr)
+ && pskb_may_pull(skb, nh_ofs + ip_len));
+ }
+ return 0;
+}
+
static int tcphdr_ok(struct sk_buff *skb)
{
int th_ofs = skb_transport_offset(skb);
- if (skb->len >= th_ofs + sizeof(struct tcphdr)) {
+ if (pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))) {
int tcp_len = tcp_hdrlen(skb);
return (tcp_len >= sizeof(struct tcphdr)
&& skb->len >= th_ofs + tcp_len);
static int udphdr_ok(struct sk_buff *skb)
{
int th_ofs = skb_transport_offset(skb);
- return skb->len >= th_ofs + sizeof(struct udphdr);
+ return pskb_may_pull(skb, th_ofs + sizeof(struct udphdr));
+}
+
+static int icmphdr_ok(struct sk_buff *skb)
+{
+ int th_ofs = skb_transport_offset(skb);
+ return pskb_may_pull(skb, th_ofs + sizeof(struct icmphdr));
}
/* Parses the Ethernet frame in 'skb', which was received on 'in_port',
int flow_extract(struct sk_buff *skb, uint16_t in_port,
struct sw_flow_key *key)
{
- struct ethhdr *mac;
- int nh_ofs, th_ofs;
+ struct ethhdr *eth;
+ struct eth_snap_hdr *esh;
int retval = 0;
+ int nh_ofs;
+ memset(key, 0, sizeof *key);
+ key->dl_vlan = htons(OFP_VLAN_NONE);
key->in_port = htons(in_port);
- key->wildcards = 0;
- memset(key->pad, '\0', sizeof(key->pad));
-
- /* This code doesn't check that skb->len is long enough to contain the
- * MAC or network header. With a 46-byte minimum length frame this
- * assumption is always correct. */
- /* Doesn't verify checksums. Should it? */
+ if (skb->len < sizeof *eth)
+ return 0;
+ if (!pskb_may_pull(skb, skb->len >= 64 ? 64 : skb->len)) {
+ return 0;
+ }
- /* Data link layer. We only support Ethernet. */
- mac = eth_hdr(skb);
- nh_ofs = sizeof(struct ethhdr);
- if (likely(ntohs(mac->h_proto) >= OFP_DL_TYPE_ETH2_CUTOFF)) {
- /* This is an Ethernet II frame */
- key->dl_type = mac->h_proto;
+ skb_reset_mac_header(skb);
+ eth = eth_hdr(skb);
+ esh = (struct eth_snap_hdr *) eth;
+ nh_ofs = sizeof *eth;
+ if (likely(ntohs(eth->h_proto) >= OFP_DL_TYPE_ETH2_CUTOFF))
+ key->dl_type = eth->h_proto;
+ else if (skb->len >= sizeof *esh && is_snap(esh)) {
+ key->dl_type = esh->ethertype;
+ nh_ofs = sizeof *esh;
} else {
- /* This is an 802.2 frame */
- if (snap_get_ethertype(skb, &key->dl_type) != -EINVAL) {
- nh_ofs += sizeof(struct snap_hdr);
- } else {
- key->dl_type = htons(OFP_DL_TYPE_NOT_ETH_TYPE);
- nh_ofs += sizeof(struct llc_pdu_un);
+ key->dl_type = htons(OFP_DL_TYPE_NOT_ETH_TYPE);
+ if (skb->len >= nh_ofs + sizeof(struct llc_pdu_un)) {
+ nh_ofs += sizeof(struct llc_pdu_un);
}
}
/* Check for a VLAN tag */
- if (likely(key->dl_type != htons(ETH_P_8021Q))) {
- key->dl_vlan = htons(OFP_VLAN_NONE);
- } else {
- struct vlan_hdr *vh = (struct vlan_hdr *)(skb_mac_header(skb) + nh_ofs);
+ if (key->dl_type == htons(ETH_P_8021Q) &&
+ skb->len >= nh_ofs + sizeof(struct vlan_hdr)) {
+ struct vlan_hdr *vh = (struct vlan_hdr*)(skb->data + nh_ofs);
key->dl_type = vh->h_vlan_encapsulated_proto;
key->dl_vlan = vh->h_vlan_TCI & htons(VLAN_VID_MASK);
- nh_ofs += sizeof(*vh);
+ nh_ofs += sizeof(struct vlan_hdr);
}
- memcpy(key->dl_src, mac->h_source, ETH_ALEN);
- memcpy(key->dl_dst, mac->h_dest, ETH_ALEN);
+ memcpy(key->dl_src, eth->h_source, ETH_ALEN);
+ memcpy(key->dl_dst, eth->h_dest, ETH_ALEN);
skb_set_network_header(skb, nh_ofs);
/* Network layer. */
- if (likely(key->dl_type == htons(ETH_P_IP))) {
+ if (key->dl_type == htons(ETH_P_IP) && iphdr_ok(skb)) {
struct iphdr *nh = ip_hdr(skb);
+ int th_ofs = nh_ofs + nh->ihl * 4;
key->nw_src = nh->saddr;
key->nw_dst = nh->daddr;
key->nw_proto = nh->protocol;
- th_ofs = nh_ofs + nh->ihl * 4;
skb_set_transport_header(skb, th_ofs);
/* Transport layer. */
/* Avoid tricking other code into
* thinking that this packet has an L4
* header. */
- goto no_proto;
+ key->nw_proto = 0;
}
} else if (key->nw_proto == IPPROTO_UDP) {
if (udphdr_ok(skb)) {
/* Avoid tricking other code into
* thinking that this packet has an L4
* header. */
- goto no_proto;
+ key->nw_proto = 0;
+ }
+ } else if (key->nw_proto == IPPROTO_ICMP) {
+ if (icmphdr_ok(skb)) {
+ struct icmphdr *icmp = icmp_hdr(skb);
+ /* The ICMP type and code fields use the 16-bit
+ * transport port fields, so we need to store them
+ * in 16-bit network byte order. */
+ key->icmp_type = htons(icmp->type);
+ key->icmp_code = htons(icmp->code);
+ } else {
+ /* Avoid tricking other code into
+ * thinking that this packet has an L4
+ * header. */
+ key->nw_proto = 0;
}
- } else {
- goto no_th;
}
} else {
retval = 1;
- goto no_th;
}
-
- return 0;
+ } else {
+ skb_reset_transport_header(skb);
}
-
- key->nw_src = 0;
- key->nw_dst = 0;
-
-no_proto:
- key->nw_proto = 0;
-
-no_th:
- key->tp_src = 0;
- key->tp_dst = 0;
return retval;
}