Skip to content

Commit

Permalink
[NETFILTER]: bridge netfilter: consolidate header pushing/pulling code
Browse files Browse the repository at this point in the history 
Consolidate the common push/pull sequences into a few helper functions.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Patrick McHardy authored and David S. Miller committed May 3, 2007
1 parent cfd6c38 commit fc38582
Show file tree
Hide file tree
Showing 2 changed files with 56 additions and 107 deletions.
25 changes: 16 additions & 9 deletions include/linux/netfilter_bridge.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -55,18 +55,25 @@ static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
return 0;
}

static inline unsigned int nf_bridge_encap_header_len(const struct sk_buff *skb)
{
switch (skb->protocol) {
case __constant_htons(ETH_P_8021Q):
return VLAN_HLEN;
case __constant_htons(ETH_P_PPP_SES):
return PPPOE_SES_HLEN;
default:
return 0;
}
}

/* This is called by the IP fragmenting code and it ensures there is
* enough room for the encapsulating header (if there is one). */
static inline int nf_bridge_pad(const struct sk_buff *skb)
static inline unsigned int nf_bridge_pad(const struct sk_buff *skb)
{
int padding = 0;

if (skb->nf_bridge && skb->protocol == htons(ETH_P_8021Q))
padding = VLAN_HLEN;
else if (skb->nf_bridge && skb->protocol == htons(ETH_P_PPP_SES))
padding = PPPOE_SES_HLEN;

return padding;
if (skb->nf_bridge)
return nf_bridge_encap_header_len(skb);
return 0;
}

struct bridge_skb_cb {
Expand Down
138 changes: 40 additions & 98 deletions net/bridge/br_netfilter.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -142,14 +142,33 @@ static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb)
return skb->nf_bridge;
}

static inline void nf_bridge_save_header(struct sk_buff *skb)
static inline void nf_bridge_push_encap_header(struct sk_buff *skb)
{
unsigned int len = nf_bridge_encap_header_len(skb);

skb_push(skb, len);
skb->network_header -= len;
}

static inline void nf_bridge_pull_encap_header(struct sk_buff *skb)
{
int header_size = ETH_HLEN;
unsigned int len = nf_bridge_encap_header_len(skb);

skb_pull(skb, len);
skb->network_header += len;
}

if (skb->protocol == htons(ETH_P_8021Q))
header_size += VLAN_HLEN;
else if (skb->protocol == htons(ETH_P_PPP_SES))
header_size += PPPOE_SES_HLEN;
static inline void nf_bridge_pull_encap_header_rcsum(struct sk_buff *skb)
{
unsigned int len = nf_bridge_encap_header_len(skb);

skb_pull_rcsum(skb, len);
skb->network_header += len;
}

static inline void nf_bridge_save_header(struct sk_buff *skb)
{
int header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);

skb_copy_from_linear_data_offset(skb, -header_size,
skb->nf_bridge->data, header_size);
Expand All @@ -162,24 +181,15 @@ static inline void nf_bridge_save_header(struct sk_buff *skb)
int nf_bridge_copy_header(struct sk_buff *skb)
{
int err;
int header_size = ETH_HLEN;

if (skb->protocol == htons(ETH_P_8021Q))
header_size += VLAN_HLEN;
else if (skb->protocol == htons(ETH_P_PPP_SES))
header_size += PPPOE_SES_HLEN;
int header_size = ETH_HLEN + nf_bridge_encap_header_len(skb);

err = skb_cow(skb, header_size);
if (err)
return err;

skb_copy_to_linear_data_offset(skb, -header_size,
skb->nf_bridge->data, header_size);

if (skb->protocol == htons(ETH_P_8021Q))
__skb_push(skb, VLAN_HLEN);
else if (skb->protocol == htons(ETH_P_PPP_SES))
__skb_push(skb, PPPOE_SES_HLEN);
__skb_push(skb, nf_bridge_encap_header_len(skb));
return 0;
}

Expand All @@ -200,13 +210,7 @@ static int br_nf_pre_routing_finish_ipv6(struct sk_buff *skb)
dst_hold(skb->dst);

skb->dev = nf_bridge->physindev;
if (skb->protocol == htons(ETH_P_8021Q)) {
skb_push(skb, VLAN_HLEN);
skb->network_header -= VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_push(skb, PPPOE_SES_HLEN);
skb->network_header -= PPPOE_SES_HLEN;
}
nf_bridge_push_encap_header(skb);
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
br_handle_frame_finish, 1);

Expand Down Expand Up @@ -284,13 +288,7 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
if (!skb->dev)
kfree_skb(skb);
else {
if (skb->protocol == htons(ETH_P_8021Q)) {
skb_pull(skb, VLAN_HLEN);
skb->network_header += VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_pull(skb, PPPOE_SES_HLEN);
skb->network_header += PPPOE_SES_HLEN;
}
nf_bridge_pull_encap_header(skb);
skb->dst->output(skb);
}
return 0;
Expand Down Expand Up @@ -356,15 +354,7 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb)
* bridged frame */
nf_bridge->mask |= BRNF_BRIDGED_DNAT;
skb->dev = nf_bridge->physindev;
if (skb->protocol ==
htons(ETH_P_8021Q)) {
skb_push(skb, VLAN_HLEN);
skb->network_header -= VLAN_HLEN;
} else if(skb->protocol ==
htons(ETH_P_PPP_SES)) {
skb_push(skb, PPPOE_SES_HLEN);
skb->network_header -= PPPOE_SES_HLEN;
}
nf_bridge_push_encap_header(skb);
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING,
skb, skb->dev, NULL,
br_nf_pre_routing_finish_bridge,
Expand All @@ -380,13 +370,7 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb)
}

skb->dev = nf_bridge->physindev;
if (skb->protocol == htons(ETH_P_8021Q)) {
skb_push(skb, VLAN_HLEN);
skb->network_header -= VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_push(skb, PPPOE_SES_HLEN);
skb->network_header -= PPPOE_SES_HLEN;
}
nf_bridge_push_encap_header(skb);
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_PRE_ROUTING, skb, skb->dev, NULL,
br_handle_frame_finish, 1);

Expand Down Expand Up @@ -536,14 +520,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,
#endif
if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
goto out;

if (skb->protocol == htons(ETH_P_8021Q)) {
skb_pull_rcsum(skb, VLAN_HLEN);
skb->network_header += VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_pull_rcsum(skb, PPPOE_SES_HLEN);
skb->network_header += PPPOE_SES_HLEN;
}
nf_bridge_pull_encap_header_rcsum(skb);
return br_nf_pre_routing_ipv6(hook, skb, in, out, okfn);
}
#ifdef CONFIG_SYSCTL
Expand All @@ -557,14 +534,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb,

if ((skb = skb_share_check(*pskb, GFP_ATOMIC)) == NULL)
goto out;

if (skb->protocol == htons(ETH_P_8021Q)) {
skb_pull_rcsum(skb, VLAN_HLEN);
skb->network_header += VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_pull_rcsum(skb, PPPOE_SES_HLEN);
skb->network_header += PPPOE_SES_HLEN;
}
nf_bridge_pull_encap_header_rcsum(skb);

if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto inhdr_error;
Expand Down Expand Up @@ -642,13 +612,7 @@ static int br_nf_forward_finish(struct sk_buff *skb)
} else {
in = *((struct net_device **)(skb->cb));
}
if (skb->protocol == htons(ETH_P_8021Q)) {
skb_push(skb, VLAN_HLEN);
skb->network_header -= VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_push(skb, PPPOE_SES_HLEN);
skb->network_header -= PPPOE_SES_HLEN;
}
nf_bridge_push_encap_header(skb);
NF_HOOK_THRESH(PF_BRIDGE, NF_BR_FORWARD, skb, in,
skb->dev, br_forward_finish, 1);
return 0;
Expand Down Expand Up @@ -682,13 +646,7 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff **pskb,
else
pf = PF_INET6;

if (skb->protocol == htons(ETH_P_8021Q)) {
skb_pull(*pskb, VLAN_HLEN);
(*pskb)->network_header += VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_pull(*pskb, PPPOE_SES_HLEN);
(*pskb)->network_header += PPPOE_SES_HLEN;
}
nf_bridge_pull_encap_header(*pskb);

nf_bridge = skb->nf_bridge;
if (skb->pkt_type == PACKET_OTHERHOST) {
Expand Down Expand Up @@ -722,15 +680,12 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb,
if (skb->protocol != htons(ETH_P_ARP)) {
if (!IS_VLAN_ARP(skb))
return NF_ACCEPT;
skb_pull(*pskb, VLAN_HLEN);
(*pskb)->network_header += VLAN_HLEN;
nf_bridge_pull_encap_header(*pskb);
}

if (arp_hdr(skb)->ar_pln != 4) {
if (IS_VLAN_ARP(skb)) {
skb_push(*pskb, VLAN_HLEN);
(*pskb)->network_header -= VLAN_HLEN;
}
if (IS_VLAN_ARP(skb))
nf_bridge_push_encap_header(*pskb);
return NF_ACCEPT;
}
*d = (struct net_device *)in;
Expand Down Expand Up @@ -777,13 +732,7 @@ static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb,
skb->pkt_type = PACKET_OTHERHOST;
nf_bridge->mask ^= BRNF_PKT_TYPE;
}
if (skb->protocol == htons(ETH_P_8021Q)) {
skb_push(skb, VLAN_HLEN);
skb->network_header -= VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_push(skb, PPPOE_SES_HLEN);
skb->network_header -= PPPOE_SES_HLEN;
}
nf_bridge_push_encap_header(skb);

NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev, skb->dev,
br_forward_finish);
Expand Down Expand Up @@ -848,14 +797,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb,
nf_bridge->mask |= BRNF_PKT_TYPE;
}

if (skb->protocol == htons(ETH_P_8021Q)) {
skb_pull(skb, VLAN_HLEN);
skb->network_header += VLAN_HLEN;
} else if (skb->protocol == htons(ETH_P_PPP_SES)) {
skb_pull(skb, PPPOE_SES_HLEN);
skb->network_header += PPPOE_SES_HLEN;
}

nf_bridge_pull_encap_header(skb);
nf_bridge_save_header(skb);

#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
Expand Down

0 comments on commit fc38582

Please sign in to comment.