| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20201120124921.32172-8-pablo@netfilter.org>
Date: Fri, 20 Nov 2020 13:49:19 +0100
From: Pablo Neira Ayuso <pablo@...filter.org>
To: netfilter-devel@...r.kernel.org
Cc: davem@...emloft.net, netdev@...r.kernel.org, kuba@...nel.org,
fw@...len.de, razor@...ckwall.org, jeremy@...zel.net,
tobias@...dekranz.com
Subject: [PATCH net-next,v5 7/9] netfilter: flowtable: use dev_fill_forward_path() to obtain egress device
The egress device in the tuple is obtained from route. Use
dev_fill_forward_path() instead to provide the real egress device for
this flow whenever this is available.
The new FLOW_OFFLOAD_XMIT_DIRECT type uses dev_queue_xmit() to transmit
ethernet frames. Cache the source and destination hardware address to
use dev_queue_xmit() to transfer packets.
The FLOW_OFFLOAD_XMIT_DIRECT replaces FLOW_OFFLOAD_XMIT_NEIGH if
dev_fill_forward_path() finds a direct transmit path.
In case of topology updates, if peer is moved to different bridge port,
the connection will time out, reconnect will result in a new entry with
the correct path. Snooping fdb updates would allow for cleaning up stale
flowtable entries.
Signed-off-by: Pablo Neira Ayuso <pablo@...filter.org>
---
v5: add note on fdb topology updates, per Jakub Kicinski.
include/net/netfilter/nf_flow_table.h | 16 +++++-
net/netfilter/nf_flow_table_core.c | 35 ++++++++++---
net/netfilter/nf_flow_table_ip.c | 72 +++++++++++++++++++++------
net/netfilter/nft_flow_offload.c | 25 ++++++++--
4 files changed, 118 insertions(+), 30 deletions(-)
diff --git a/include/net/netfilter/nf_flow_table.h b/include/net/netfilter/nf_flow_table.h
index 963f99fb1c06..83110e4705c0 100644
--- a/include/net/netfilter/nf_flow_table.h
+++ b/include/net/netfilter/nf_flow_table.h
@@ -92,6 +92,7 @@ enum flow_offload_tuple_dir {
enum flow_offload_xmit_type {
FLOW_OFFLOAD_XMIT_NEIGH = 0,
FLOW_OFFLOAD_XMIT_XFRM,
+ FLOW_OFFLOAD_XMIT_DIRECT,
};
struct flow_offload_tuple {
@@ -120,8 +121,14 @@ struct flow_offload_tuple {
xmit_type:2;
u16 mtu;
-
- struct dst_entry *dst_cache;
+ union {
+ struct dst_entry *dst_cache;
+ struct {
+ u32 ifidx;
+ u8 h_source[ETH_ALEN];
+ u8 h_dest[ETH_ALEN];
+ } out;
+ };
};
struct flow_offload_tuple_rhash {
@@ -168,6 +175,11 @@ struct nf_flow_route {
struct {
u32 ifindex;
} in;
+ struct {
+ u32 ifindex;
+ u8 h_source[ETH_ALEN];
+ u8 h_dest[ETH_ALEN];
+ } out;
enum flow_offload_xmit_type xmit_type;
} tuple[FLOW_OFFLOAD_DIR_MAX];
};
diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index 27b4315d7b96..751bc1c27c16 100644
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -81,9 +81,6 @@ static int flow_offload_fill_route(struct flow_offload *flow,
struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
struct dst_entry *dst = route->tuple[dir].dst;
- if (!dst_hold_safe(route->tuple[dir].dst))
- return -1;
-
switch (flow_tuple->l3proto) {
case NFPROTO_IPV4:
flow_tuple->mtu = ip_dst_mtu_maybe_forward(dst, true);
@@ -94,12 +91,36 @@ static int flow_offload_fill_route(struct flow_offload *flow,
}
flow_tuple->iifidx = route->tuple[dir].in.ifindex;
+
+ switch (route->tuple[dir].xmit_type) {
+ case FLOW_OFFLOAD_XMIT_DIRECT:
+ memcpy(flow_tuple->out.h_dest, route->tuple[dir].out.h_dest,
+ ETH_ALEN);
+ memcpy(flow_tuple->out.h_source, route->tuple[dir].out.h_source,
+ ETH_ALEN);
+ flow_tuple->out.ifidx = route->tuple[dir].out.ifindex;
+ break;
+ case FLOW_OFFLOAD_XMIT_XFRM:
+ case FLOW_OFFLOAD_XMIT_NEIGH:
+ if (!dst_hold_safe(route->tuple[dir].dst))
+ return -1;
+
+ flow_tuple->dst_cache = dst;
+ break;
+ }
flow_tuple->xmit_type = route->tuple[dir].xmit_type;
- flow_tuple->dst_cache = dst;
return 0;
}
+static void nft_flow_dst_release(struct flow_offload *flow,
+ enum flow_offload_tuple_dir dir)
+{
+ if (flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_NEIGH ||
+ flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)
+ dst_release(flow->tuplehash[dir].tuple.dst_cache);
+}
+
int flow_offload_route_init(struct flow_offload *flow,
const struct nf_flow_route *route)
{
@@ -118,7 +139,7 @@ int flow_offload_route_init(struct flow_offload *flow,
return 0;
err_route_reply:
- dst_release(route->tuple[FLOW_OFFLOAD_DIR_ORIGINAL].dst);
+ nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
return err;
}
@@ -169,8 +190,8 @@ static void flow_offload_fixup_ct(struct nf_conn *ct)
static void flow_offload_route_release(struct flow_offload *flow)
{
- dst_release(flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_cache);
- dst_release(flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_cache);
+ nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
+ nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_REPLY);
}
void flow_offload_free(struct flow_offload *flow)
diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index af49672bd38d..ae0b008c639a 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -248,6 +248,24 @@ static unsigned int nf_flow_xmit_xfrm(struct sk_buff *skb,
return NF_STOLEN;
}
+static unsigned int nf_flow_queue_xmit(struct net *net, struct sk_buff *skb,
+ const struct flow_offload_tuple_rhash *tuplehash,
+ unsigned short type)
+{
+ struct net_device *outdev;
+
+ outdev = dev_get_by_index_rcu(net, tuplehash->tuple.out.ifidx);
+ if (!outdev)
+ return NF_DROP;
+
+ skb->dev = outdev;
+ dev_hard_header(skb, skb->dev, type, tuplehash->tuple.out.h_dest,
+ tuplehash->tuple.out.h_source, skb->len);
+ dev_queue_xmit(skb);
+
+ return NF_STOLEN;
+}
+
unsigned int
nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
const struct nf_hook_state *state)
@@ -262,6 +280,7 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
unsigned int thoff;
struct iphdr *iph;
__be32 nexthop;
+ int ret;
if (skb->protocol != htons(ETH_P_IP))
return NF_ACCEPT;
@@ -303,22 +322,32 @@ nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
if (flow_table->flags & NF_FLOWTABLE_COUNTER)
nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
- rt = (struct rtable *)tuplehash->tuple.dst_cache;
-
if (unlikely(tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)) {
+ rt = (struct rtable *)tuplehash->tuple.dst_cache;
memset(skb->cb, 0, sizeof(struct inet_skb_parm));
IPCB(skb)->iif = skb->dev->ifindex;
IPCB(skb)->flags = IPSKB_FORWARDED;
return nf_flow_xmit_xfrm(skb, state, &rt->dst);
}
- outdev = rt->dst.dev;
- skb->dev = outdev;
- nexthop = rt_nexthop(rt, flow->tuplehash[!dir].tuple.src_v4.s_addr);
- skb_dst_set_noref(skb, &rt->dst);
- neigh_xmit(NEIGH_ARP_TABLE, outdev, &nexthop, skb);
+ switch (tuplehash->tuple.xmit_type) {
+ case FLOW_OFFLOAD_XMIT_NEIGH:
+ rt = (struct rtable *)tuplehash->tuple.dst_cache;
+ outdev = rt->dst.dev;
+ skb->dev = outdev;
+ nexthop = rt_nexthop(rt, flow->tuplehash[!dir].tuple.src_v4.s_addr);
+ skb_dst_set_noref(skb, &rt->dst);
+ neigh_xmit(NEIGH_ARP_TABLE, outdev, &nexthop, skb);
+ ret = NF_STOLEN;
+ break;
+ case FLOW_OFFLOAD_XMIT_DIRECT:
+ ret = nf_flow_queue_xmit(state->net, skb, tuplehash, ETH_P_IP);
+ if (ret == NF_DROP)
+ flow_offload_teardown(flow);
+ break;
+ }
- return NF_STOLEN;
+ return ret;
}
EXPORT_SYMBOL_GPL(nf_flow_offload_ip_hook);
@@ -504,6 +533,7 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
struct net_device *outdev;
struct ipv6hdr *ip6h;
struct rt6_info *rt;
+ int ret;
if (skb->protocol != htons(ETH_P_IPV6))
return NF_ACCEPT;
@@ -545,21 +575,31 @@ nf_flow_offload_ipv6_hook(void *priv, struct sk_buff *skb,
if (flow_table->flags & NF_FLOWTABLE_COUNTER)
nf_ct_acct_update(flow->ct, tuplehash->tuple.dir, skb->len);
- rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
-
if (unlikely(tuplehash->tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)) {
+ rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
memset(skb->cb, 0, sizeof(struct inet6_skb_parm));
IP6CB(skb)->iif = skb->dev->ifindex;
IP6CB(skb)->flags = IP6SKB_FORWARDED;
return nf_flow_xmit_xfrm(skb, state, &rt->dst);
}
- outdev = rt->dst.dev;
- skb->dev = outdev;
- nexthop = rt6_nexthop(rt, &flow->tuplehash[!dir].tuple.src_v6);
- skb_dst_set_noref(skb, &rt->dst);
- neigh_xmit(NEIGH_ND_TABLE, outdev, nexthop, skb);
+ switch (tuplehash->tuple.xmit_type) {
+ case FLOW_OFFLOAD_XMIT_NEIGH:
+ rt = (struct rt6_info *)tuplehash->tuple.dst_cache;
+ outdev = rt->dst.dev;
+ skb->dev = outdev;
+ nexthop = rt6_nexthop(rt, &flow->tuplehash[!dir].tuple.src_v6);
+ skb_dst_set_noref(skb, &rt->dst);
+ neigh_xmit(NEIGH_ND_TABLE, outdev, nexthop, skb);
+ ret = NF_STOLEN;
+ break;
+ case FLOW_OFFLOAD_XMIT_DIRECT:
+ ret = nf_flow_queue_xmit(state->net, skb, tuplehash, ETH_P_IPV6);
+ if (ret == NF_DROP)
+ flow_offload_teardown(flow);
+ break;
+ }
- return NF_STOLEN;
+ return ret;
}
EXPORT_SYMBOL_GPL(nf_flow_offload_ipv6_hook);
diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
index 15f5a3b38253..68d03569c293 100644
--- a/net/netfilter/nft_flow_offload.c
+++ b/net/netfilter/nft_flow_offload.c
@@ -39,12 +39,11 @@ static void nft_default_forward_path(struct nf_flow_route *route,
static int nft_dev_fill_forward_path(const struct nf_flow_route *route,
const struct dst_entry *dst_cache,
const struct nf_conn *ct,
- enum ip_conntrack_dir dir,
+ enum ip_conntrack_dir dir, u8 *ha,
struct net_device_path_stack *stack)
{
const void *daddr = &ct->tuplehash[!dir].tuple.src.u3;
struct net_device *dev = dst_cache->dev;
- unsigned char ha[ETH_ALEN];
struct neighbour *n;
u8 nud_state;
@@ -66,10 +65,14 @@ static int nft_dev_fill_forward_path(const struct nf_flow_route *route,
struct nft_forward_info {
const struct net_device *indev;
+ u8 h_source[ETH_ALEN];
+ u8 h_dest[ETH_ALEN];
+ enum flow_offload_xmit_type xmit_type;
};
static void nft_dev_path_info(const struct net_device_path_stack *stack,
- struct nft_forward_info *info)
+ struct nft_forward_info *info,
+ unsigned char *ha)
{
const struct net_device_path *path;
int i;
@@ -79,10 +82,14 @@ static void nft_dev_path_info(const struct net_device_path_stack *stack,
switch (path->type) {
case DEV_PATH_ETHERNET:
info->indev = path->dev;
+ memcpy(info->h_dest, path->dev->dev_addr, ETH_ALEN);
+ memcpy(info->h_source, ha, ETH_ALEN);
break;
case DEV_PATH_VLAN:
break;
case DEV_PATH_BRIDGE:
+ memcpy(info->h_dest, path->dev->dev_addr, ETH_ALEN);
+ info->xmit_type = FLOW_OFFLOAD_XMIT_DIRECT;
break;
}
}
@@ -113,14 +120,22 @@ static void nft_dev_forward_path(struct nf_flow_route *route,
const struct dst_entry *dst = route->tuple[dir].dst;
struct net_device_path_stack stack;
struct nft_forward_info info = {};
+ unsigned char ha[ETH_ALEN];
- if (nft_dev_fill_forward_path(route, dst, ct, dir, &stack) >= 0)
- nft_dev_path_info(&stack, &info);
+ if (nft_dev_fill_forward_path(route, dst, ct, dir, ha, &stack) >= 0)
+ nft_dev_path_info(&stack, &info, ha);
if (!info.indev || !nft_flowtable_find_dev(info.indev, ft))
return;
route->tuple[!dir].in.ifindex = info.indev->ifindex;
+
+ if (info.xmit_type == FLOW_OFFLOAD_XMIT_DIRECT) {
+ memcpy(route->tuple[dir].out.h_dest, info.h_source, ETH_ALEN);
+ memcpy(route->tuple[dir].out.h_source, info.h_dest, ETH_ALEN);
+ route->tuple[dir].out.ifindex = info.indev->ifindex;
+ route->tuple[dir].xmit_type = info.xmit_type;
+ }
}
static int nft_flow_route(const struct nft_pktinfo *pkt,
--
2.20.1
Powered by blists - more mailing lists