X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=datapath%2Factions.c;h=b75aecdace46d3e7c659918f0bcb9bd0acb81b54;hb=722d19c504351a3e1a6f64e5a01ff9806eb089a4;hp=402041180cf79ea310f2ded3e5895bf9f550e4a9;hpb=f2459fe7d91c4c325dfaa3ed18f56200b63ae27e;p=openvswitch

diff --git a/datapath/actions.c b/datapath/actions.c
index 40204118..b75aecda 100644
--- a/datapath/actions.c
+++ b/datapath/actions.c
@@ -14,6 +14,7 @@
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/in6.h>
+#include <linux/if_arp.h>
 #include <linux/if_vlan.h>
 #include <net/inet_ecn.h>
 #include <net/ip.h>
@@ -24,28 +25,15 @@
 #include "openvswitch/datapath-protocol.h"
 #include "vport.h"
 
-static struct sk_buff *
-make_writable(struct sk_buff *skb, unsigned min_headroom, gfp_t gfp)
+static struct sk_buff *make_writable(struct sk_buff *skb, unsigned min_headroom, gfp_t gfp)
 {
-	if (skb_shared(skb) || skb_cloned(skb)) {
+	if (skb_cloned(skb)) {
 		struct sk_buff *nskb;
 		unsigned headroom = max(min_headroom, skb_headroom(skb));
 
 		nskb = skb_copy_expand(skb, headroom, skb_tailroom(skb), gfp);
 		if (nskb) {
-#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
-			/* Before 2.6.24 these fields were not copied when
-			 * doing an skb_copy_expand. */
-			nskb->ip_summed = skb->ip_summed;
-			nskb->csum = skb->csum;
-#endif
-#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID)
-			/* These fields are copied in skb_clone but not in
-			 * skb_copy or related functions.  We need to manually
-			 * copy them over here. */
-			nskb->proto_data_valid = skb->proto_data_valid;
-			nskb->proto_csum_blank = skb->proto_csum_blank;
-#endif
+			set_skb_csum_bits(skb, nskb);
 			kfree_skb(skb);
 			return nskb;
 		}
@@ -59,20 +47,13 @@ make_writable(struct sk_buff *skb, unsigned min_headroom, gfp_t gfp)
 	return NULL;
 }
 
-static void set_tunnel(struct sk_buff *skb, struct odp_flow_key *key,
-		       __be32 tun_id)
-{
-	OVS_CB(skb)->tun_id = key->tun_id = tun_id;
-}
-
-static struct sk_buff *
-vlan_pull_tag(struct sk_buff *skb)
+static struct sk_buff *vlan_pull_tag(struct sk_buff *skb)
 {
 	struct vlan_ethhdr *vh = vlan_eth_hdr(skb);
 	struct ethhdr *eh;
 
 	/* Verify we were given a vlan packet */
-	if (vh->h_vlan_proto != htons(ETH_P_8021Q))
+	if (vh->h_vlan_proto != htons(ETH_P_8021Q) || skb->len < VLAN_ETH_HLEN)
 		return skb;
 
 	if (OVS_CB(skb)->ip_summed == OVS_CSUM_COMPLETE)
@@ -89,22 +70,19 @@ vlan_pull_tag(struct sk_buff *skb)
 	return skb;
 }
 
-
-static struct sk_buff *
-modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
-		struct odp_flow_key *key, const union odp_action *a,
-		int n_actions, gfp_t gfp)
+static struct sk_buff *modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
+				       const struct odp_flow_key *key,
+				       const union odp_action *a, int n_actions,
+				       gfp_t gfp)
 {
 	u16 tci, mask;
 
 	if (a->type == ODPAT_SET_VLAN_VID) {
 		tci = ntohs(a->vlan_vid.vlan_vid);
 		mask = VLAN_VID_MASK;
-		key->dl_vlan = a->vlan_vid.vlan_vid;
 	} else {
 		tci = a->vlan_pcp.vlan_pcp << VLAN_PCP_SHIFT;
 		mask = VLAN_PCP_MASK;
-		key->dl_vlan_pcp = a->vlan_pcp.vlan_pcp;
 	}
 
 	skb = make_writable(skb, VLAN_HLEN, gfp);
@@ -113,8 +91,14 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 
 	if (skb->protocol == htons(ETH_P_8021Q)) {
 		/* Modify vlan id, but maintain other TCI values */
-		struct vlan_ethhdr *vh = vlan_eth_hdr(skb);
-		__be16 old_tci = vh->h_vlan_TCI;
+		struct vlan_ethhdr *vh;
+		__be16 old_tci;
+
+		if (skb->len < VLAN_ETH_HLEN)
+			return skb;
+
+		vh = vlan_eth_hdr(skb);
+		old_tci = vh->h_vlan_TCI;
 
 		vh->h_vlan_TCI = htons((ntohs(vh->h_vlan_TCI) & ~mask) | tci);
 
@@ -125,6 +109,8 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 						~skb->csum);
 		}
 	} else {
+		int err;
+
 		/* Add vlan header */
 
 		/* Set up checksumming pointers for checksum-deferred packets
@@ -132,7 +118,11 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 		 * when we send the packet out on the wire, and it will fail at
 		 * that point because skb_checksum_setup() will not look inside
 		 * an 802.1Q header. */
-		vswitch_skb_checksum_setup(skb);
+		err = vswitch_skb_checksum_setup(skb);
+		if (unlikely(err)) {
+			kfree_skb(skb);
+			return ERR_PTR(err);
+		}
 
 		/* GSO is not implemented for packets with an 802.1Q header, so
 		 * we have to do segmentation before we add that header.
@@ -169,9 +159,8 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 				segs = __vlan_put_tag(segs, tci);
 				err = -ENOMEM;
 				if (segs) {
-					struct odp_flow_key segkey = *key;
 					err = execute_actions(dp, segs,
-							      &segkey, a + 1,
+							      key, a + 1,
 							      n_actions - 1,
 							      gfp);
 				}
@@ -211,32 +200,26 @@ modify_vlan_tci(struct datapath *dp, struct sk_buff *skb,
 	return skb;
 }
 
-static struct sk_buff *strip_vlan(struct sk_buff *skb,
-				  struct odp_flow_key *key, gfp_t gfp)
+static struct sk_buff *strip_vlan(struct sk_buff *skb, gfp_t gfp)
 {
 	skb = make_writable(skb, 0, gfp);
-	if (skb) {
+	if (skb)
 		vlan_pull_tag(skb);
-		key->dl_vlan = htons(ODP_VLAN_NONE);
-	}
+
 	return skb;
 }
 
 static struct sk_buff *set_dl_addr(struct sk_buff *skb,
-				   struct odp_flow_key *key,
 				   const struct odp_action_dl_addr *a,
 				   gfp_t gfp)
 {
 	skb = make_writable(skb, 0, gfp);
 	if (skb) {
 		struct ethhdr *eh = eth_hdr(skb);
-		if (a->type == ODPAT_SET_DL_SRC) {
+		if (a->type == ODPAT_SET_DL_SRC)
 			memcpy(eh->h_source, a->dl_addr, ETH_ALEN);
-			memcpy(key->dl_src, a->dl_addr, ETH_ALEN);
-		} else {
+		else
 			memcpy(eh->h_dest, a->dl_addr, ETH_ALEN);
-			memcpy(key->dl_dst, a->dl_addr, ETH_ALEN);
-		}
 	}
 	return skb;
 }
@@ -261,45 +244,60 @@ static void update_csum(__sum16 *sum, struct sk_buff *skb,
 				csum_unfold(*sum)));
 }
 
+static bool is_ip(struct sk_buff *skb, const struct odp_flow_key *key)
+{
+	return (key->dl_type == htons(ETH_P_IP) &&
+		skb->transport_header > skb->network_header);
+}
+
+static __sum16 *get_l4_checksum(struct sk_buff *skb, const struct odp_flow_key *key)
+{
+	int transport_len = skb->len - skb_transport_offset(skb);
+	if (key->nw_proto == IPPROTO_TCP) {
+		if (likely(transport_len >= sizeof(struct tcphdr)))
+			return &tcp_hdr(skb)->check;
+	} else if (key->nw_proto == IPPROTO_UDP) {
+		if (likely(transport_len >= sizeof(struct udphdr)))
+			return &udp_hdr(skb)->check;
+	}
+	return NULL;
+}
+
 static struct sk_buff *set_nw_addr(struct sk_buff *skb,
-				   struct odp_flow_key *key,
+				   const struct odp_flow_key *key,
 				   const struct odp_action_nw_addr *a,
 				   gfp_t gfp)
 {
-	if (key->dl_type != htons(ETH_P_IP))
+	struct iphdr *nh;
+	__sum16 *check;
+	__be32 *nwaddr;
+
+	if (unlikely(!is_ip(skb, key)))
 		return skb;
 
 	skb = make_writable(skb, 0, gfp);
-	if (skb) {
-		struct iphdr *nh = ip_hdr(skb);
-		u32 *f = a->type == ODPAT_SET_NW_SRC ? &nh->saddr : &nh->daddr;
-		u32 old = *f;
-		u32 new = a->nw_addr;
-
-		if (key->nw_proto == IPPROTO_TCP) {
-			struct tcphdr *th = tcp_hdr(skb);
-			update_csum(&th->check, skb, old, new, 1);
-		} else if (key->nw_proto == IPPROTO_UDP) {
-			struct udphdr *th = udp_hdr(skb);
-			update_csum(&th->check, skb, old, new, 1);
-		}
-		update_csum(&nh->check, skb, old, new, 0);
-		*f = new;
+	if (unlikely(!skb))
+		return NULL;
+
+	nh = ip_hdr(skb);
+	nwaddr = a->type == ODPAT_SET_NW_SRC ? &nh->saddr : &nh->daddr;
+
+	check = get_l4_checksum(skb, key);
+	if (likely(check))
+		update_csum(check, skb, *nwaddr, a->nw_addr, 1);
+	update_csum(&nh->check, skb, *nwaddr, a->nw_addr, 0);
+
+	*nwaddr = a->nw_addr;
 
-		if (a->type == ODPAT_SET_NW_SRC)
-			key->nw_src = a->nw_addr;
-		else
-			key->nw_dst = a->nw_addr;
-	}
 	return skb;
 }
 
 static struct sk_buff *set_nw_tos(struct sk_buff *skb,
-				   struct odp_flow_key *key,
+				   const struct odp_flow_key *key,
 				   const struct odp_action_nw_tos *a,
 				   gfp_t gfp)
 {
-	if (key->dl_type != htons(ETH_P_IP))
+	if (unlikely(!is_ip(skb, key)))
 		return skb;
 
 	skb = make_writable(skb, 0, gfp);
@@ -311,61 +309,80 @@ static struct sk_buff *set_nw_tos(struct sk_buff *skb,
 
 		/* Set the DSCP bits and preserve the ECN bits. */
 		new = a->nw_tos | (nh->tos & INET_ECN_MASK);
-		update_csum(&nh->check, skb, htons((uint16_t)old),
-				htons((uint16_t)new), 0);
+		update_csum(&nh->check, skb, htons((u16)old),
+			    htons((u16)new), 0);
 		*f = new;
-		key->nw_tos = a->nw_tos;
 	}
 	return skb;
 }
 
-static struct sk_buff *
-set_tp_port(struct sk_buff *skb, struct odp_flow_key *key,
-	    const struct odp_action_tp_port *a,
-	    gfp_t gfp)
+static struct sk_buff *set_tp_port(struct sk_buff *skb,
+				   const struct odp_flow_key *key,
+				   const struct odp_action_tp_port *a, gfp_t gfp)
 {
-	int check_ofs;
+	struct udphdr *th;
+	__sum16 *check;
+	__be16 *port;
 
-	if (key->dl_type != htons(ETH_P_IP))
+	if (unlikely(!is_ip(skb, key)))
 		return skb;
 
-	if (key->nw_proto == IPPROTO_TCP)
-		check_ofs = offsetof(struct tcphdr, check);
-	else if (key->nw_proto == IPPROTO_UDP)
-		check_ofs = offsetof(struct udphdr, check);
-	else
+	skb = make_writable(skb, 0, gfp);
+	if (unlikely(!skb))
+		return NULL;
+
+	/* Must follow make_writable() since that can move the skb data. */
+	check = get_l4_checksum(skb, key);
+	if (unlikely(!check))
 		return skb;
 
-	skb = make_writable(skb, 0, gfp);
-	if (skb) {
-		struct udphdr *th = udp_hdr(skb);
-		u16 *f = a->type == ODPAT_SET_TP_SRC ? &th->source : &th->dest;
-		u16 old = *f;
-		u16 new = a->tp_port;
-		update_csum((u16*)(skb_transport_header(skb) + check_ofs), 
-				skb, old, new, 0);
-		*f = new;
-		if (a->type == ODPAT_SET_TP_SRC)
-			key->tp_src = a->tp_port;
-		else
-			key->tp_dst = a->tp_port;
-	}
+	/*
+	 * Update port and checksum.
+	 *
+	 * This is OK because source and destination port numbers are at the
+	 * same offsets in both UDP and TCP headers, and get_l4_checksum() only
+	 * supports those protocols.
+	 */
+	th = udp_hdr(skb);
+	port = a->type == ODPAT_SET_TP_SRC ? &th->source : &th->dest;
+	update_csum(check, skb, *port, a->tp_port, 0);
+	*port = a->tp_port;
+
 	return skb;
 }
 
-static inline unsigned packet_length(const struct sk_buff *skb)
+/**
+ * is_spoofed_arp - check for invalid ARP packet
+ *
+ * @skb: skbuff containing an Ethernet packet, with network header pointing
+ * just past the Ethernet and optional 802.1Q header.
+ * @key: flow key extracted from @skb by flow_extract()
+ *
+ * Returns true if @skb is an invalid Ethernet+IPv4 ARP packet: one with screwy
+ * or truncated header fields or one whose inner and outer Ethernet address
+ * differ.
+ */
+static bool is_spoofed_arp(struct sk_buff *skb, const struct odp_flow_key *key)
 {
-	unsigned length = skb->len - ETH_HLEN;
-	if (skb->protocol == htons(ETH_P_8021Q))
-		length -= VLAN_HLEN;
-	return length;
+	struct arp_eth_header *arp;
+
+	if (key->dl_type != htons(ETH_P_ARP))
+		return false;
+
+	if (skb_network_offset(skb) + sizeof(struct arp_eth_header) > skb->len)
+		return true;
+
+	arp = (struct arp_eth_header *)skb_network_header(skb);
+	return (arp->ar_hrd != htons(ARPHRD_ETHER) ||
+		arp->ar_pro != htons(ETH_P_IP) ||
+		arp->ar_hln != ETH_ALEN ||
+		arp->ar_pln != 4 ||
+		compare_ether_addr(arp->ar_sha, eth_hdr(skb)->h_source));
 }
 
-static void
-do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
+static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
 {
 	struct dp_port *p;
-	int mtu;
 
 	if (!skb)
 		goto error;
@@ -374,13 +391,6 @@ do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
 	if (!p)
 		goto error;
 
-	mtu = vport_get_mtu(p->vport);
-	if (packet_length(skb) > mtu && !skb_is_gso(skb)) {
-		printk(KERN_WARNING "%s: dropped over-mtu packet: %d > %d\n",
-		       dp_name(dp), packet_length(skb), mtu);
-		goto error;
-	}
-
 	vport_send(p->vport, skb);
 	return;
 
@@ -414,8 +424,8 @@ static int output_group(struct datapath *dp, __u16 group,
 	return prev_port;
 }
 
-static int
-output_control(struct datapath *dp, struct sk_buff *skb, u32 arg, gfp_t gfp)
+static int output_control(struct datapath *dp, struct sk_buff *skb, u32 arg,
+			  gfp_t gfp)
 {
 	skb = skb_clone(skb, gfp);
 	if (!skb)
@@ -447,7 +457,7 @@ static void sflow_sample(struct datapath *dp, struct sk_buff *skb,
 
 /* Execute a list of actions against 'skb'. */
 int execute_actions(struct datapath *dp, struct sk_buff *skb,
-		    struct odp_flow_key *key,
+		    const struct odp_flow_key *key,
 		    const union odp_action *a, int n_actions,
 		    gfp_t gfp)
 {
@@ -456,6 +466,7 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 	 * then freeing the original skbuff is wasteful.  So the following code
 	 * is slightly obscure just to avoid that. */
 	int prev_port = -1;
+	u32 priority = skb->priority;
 	int err;
 
 	if (dp->sflow_probability) {
@@ -471,7 +482,6 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 	OVS_CB(skb)->tun_id = 0;
 
 	for (; n_actions > 0; a++, n_actions--) {
-		WARN_ON_ONCE(skb_shared(skb));
 		if (prev_port != -1) {
 			do_output(dp, skb_clone(skb, gfp), prev_port);
 			prev_port = -1;
@@ -496,7 +506,7 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 			break;
 
 		case ODPAT_SET_TUNNEL:
-			set_tunnel(skb, key, a->tunnel.tun_id);
+			OVS_CB(skb)->tun_id = a->tunnel.tun_id;
 			break;
 
 		case ODPAT_SET_VLAN_VID:
@@ -507,12 +517,12 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 			break;
 
 		case ODPAT_STRIP_VLAN:
-			skb = strip_vlan(skb, key, gfp);
+			skb = strip_vlan(skb, gfp);
 			break;
 
 		case ODPAT_SET_DL_SRC:
 		case ODPAT_SET_DL_DST:
-			skb = set_dl_addr(skb, key, &a->dl_addr, gfp);
+			skb = set_dl_addr(skb, &a->dl_addr, gfp);
 			break;
 
 		case ODPAT_SET_NW_SRC:
@@ -528,10 +538,24 @@ int execute_actions(struct datapath *dp, struct sk_buff *skb,
 		case ODPAT_SET_TP_DST:
 			skb = set_tp_port(skb, key, &a->tp_port, gfp);
 			break;
+
+		case ODPAT_SET_PRIORITY:
+			skb->priority = a->priority.priority;
+			break;
+
+		case ODPAT_POP_PRIORITY:
+			skb->priority = priority;
+			break;
+
+		case ODPAT_DROP_SPOOFED_ARP:
+			if (unlikely(is_spoofed_arp(skb, key)))
+				goto exit;
+			break;
 		}
 		if (!skb)
 			return -ENOMEM;
 	}
+exit:
 	if (prev_port != -1)
 		do_output(dp, skb, prev_port);
 	else