aboutsummaryrefslogtreecommitdiff
path: root/net/netfilter/xt_TCPMSS.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/netfilter/xt_TCPMSS.c')
-rw-r--r--net/netfilter/xt_TCPMSS.c58
1 files changed, 27 insertions, 31 deletions
diff --git a/net/netfilter/xt_TCPMSS.c b/net/netfilter/xt_TCPMSS.c
index d40f7e4b128..07435a602b1 100644
--- a/net/netfilter/xt_TCPMSS.c
+++ b/net/netfilter/xt_TCPMSS.c
@@ -39,7 +39,7 @@ optlen(const u_int8_t *opt, unsigned int offset)
}
static int
-tcpmss_mangle_packet(struct sk_buff **pskb,
+tcpmss_mangle_packet(struct sk_buff *skb,
const struct xt_tcpmss_info *info,
unsigned int tcphoff,
unsigned int minlen)
@@ -50,11 +50,11 @@ tcpmss_mangle_packet(struct sk_buff **pskb,
u16 newmss;
u8 *opt;
- if (!skb_make_writable(pskb, (*pskb)->len))
+ if (!skb_make_writable(skb, skb->len))
return -1;
- tcplen = (*pskb)->len - tcphoff;
- tcph = (struct tcphdr *)(skb_network_header(*pskb) + tcphoff);
+ tcplen = skb->len - tcphoff;
+ tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
/* Since it passed flags test in tcp match, we know it is is
not a fragment, and has data >= tcp header length. SYN
@@ -64,19 +64,19 @@ tcpmss_mangle_packet(struct sk_buff **pskb,
if (tcplen != tcph->doff*4) {
if (net_ratelimit())
printk(KERN_ERR "xt_TCPMSS: bad length (%u bytes)\n",
- (*pskb)->len);
+ skb->len);
return -1;
}
if (info->mss == XT_TCPMSS_CLAMP_PMTU) {
- if (dst_mtu((*pskb)->dst) <= minlen) {
+ if (dst_mtu(skb->dst) <= minlen) {
if (net_ratelimit())
printk(KERN_ERR "xt_TCPMSS: "
"unknown or invalid path-MTU (%u)\n",
- dst_mtu((*pskb)->dst));
+ dst_mtu(skb->dst));
return -1;
}
- newmss = dst_mtu((*pskb)->dst) - minlen;
+ newmss = dst_mtu(skb->dst) - minlen;
} else
newmss = info->mss;
@@ -95,7 +95,7 @@ tcpmss_mangle_packet(struct sk_buff **pskb,
opt[i+2] = (newmss & 0xff00) >> 8;
opt[i+3] = newmss & 0x00ff;
- nf_proto_csum_replace2(&tcph->check, *pskb,
+ nf_proto_csum_replace2(&tcph->check, skb,
htons(oldmss), htons(newmss), 0);
return 0;
}
@@ -104,57 +104,53 @@ tcpmss_mangle_packet(struct sk_buff **pskb,
/*
* MSS Option not found ?! add it..
*/
- if (skb_tailroom((*pskb)) < TCPOLEN_MSS) {
- struct sk_buff *newskb;
-
- newskb = skb_copy_expand(*pskb, skb_headroom(*pskb),
- TCPOLEN_MSS, GFP_ATOMIC);
- if (!newskb)
+ if (skb_tailroom(skb) < TCPOLEN_MSS) {
+ if (pskb_expand_head(skb, 0,
+ TCPOLEN_MSS - skb_tailroom(skb),
+ GFP_ATOMIC))
return -1;
- kfree_skb(*pskb);
- *pskb = newskb;
- tcph = (struct tcphdr *)(skb_network_header(*pskb) + tcphoff);
+ tcph = (struct tcphdr *)(skb_network_header(skb) + tcphoff);
}
- skb_put((*pskb), TCPOLEN_MSS);
+ skb_put(skb, TCPOLEN_MSS);
opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
memmove(opt + TCPOLEN_MSS, opt, tcplen - sizeof(struct tcphdr));
- nf_proto_csum_replace2(&tcph->check, *pskb,
+ nf_proto_csum_replace2(&tcph->check, skb,
htons(tcplen), htons(tcplen + TCPOLEN_MSS), 1);
opt[0] = TCPOPT_MSS;
opt[1] = TCPOLEN_MSS;
opt[2] = (newmss & 0xff00) >> 8;
opt[3] = newmss & 0x00ff;
- nf_proto_csum_replace4(&tcph->check, *pskb, 0, *((__be32 *)opt), 0);
+ nf_proto_csum_replace4(&tcph->check, skb, 0, *((__be32 *)opt), 0);
oldval = ((__be16 *)tcph)[6];
tcph->doff += TCPOLEN_MSS/4;
- nf_proto_csum_replace2(&tcph->check, *pskb,
+ nf_proto_csum_replace2(&tcph->check, skb,
oldval, ((__be16 *)tcph)[6], 0);
return TCPOLEN_MSS;
}
static unsigned int
-xt_tcpmss_target4(struct sk_buff **pskb,
+xt_tcpmss_target4(struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
const struct xt_target *target,
const void *targinfo)
{
- struct iphdr *iph = ip_hdr(*pskb);
+ struct iphdr *iph = ip_hdr(skb);
__be16 newlen;
int ret;
- ret = tcpmss_mangle_packet(pskb, targinfo, iph->ihl * 4,
+ ret = tcpmss_mangle_packet(skb, targinfo, iph->ihl * 4,
sizeof(*iph) + sizeof(struct tcphdr));
if (ret < 0)
return NF_DROP;
if (ret > 0) {
- iph = ip_hdr(*pskb);
+ iph = ip_hdr(skb);
newlen = htons(ntohs(iph->tot_len) + ret);
nf_csum_replace2(&iph->check, iph->tot_len, newlen);
iph->tot_len = newlen;
@@ -164,30 +160,30 @@ xt_tcpmss_target4(struct sk_buff **pskb,
#if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
static unsigned int
-xt_tcpmss_target6(struct sk_buff **pskb,
+xt_tcpmss_target6(struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
const struct xt_target *target,
const void *targinfo)
{
- struct ipv6hdr *ipv6h = ipv6_hdr(*pskb);
+ struct ipv6hdr *ipv6h = ipv6_hdr(skb);
u8 nexthdr;
int tcphoff;
int ret;
nexthdr = ipv6h->nexthdr;
- tcphoff = ipv6_skip_exthdr(*pskb, sizeof(*ipv6h), &nexthdr);
+ tcphoff = ipv6_skip_exthdr(skb, sizeof(*ipv6h), &nexthdr);
if (tcphoff < 0) {
WARN_ON(1);
return NF_DROP;
}
- ret = tcpmss_mangle_packet(pskb, targinfo, tcphoff,
+ ret = tcpmss_mangle_packet(skb, targinfo, tcphoff,
sizeof(*ipv6h) + sizeof(struct tcphdr));
if (ret < 0)
return NF_DROP;
if (ret > 0) {
- ipv6h = ipv6_hdr(*pskb);
+ ipv6h = ipv6_hdr(skb);
ipv6h->payload_len = htons(ntohs(ipv6h->payload_len) + ret);
}
return XT_CONTINUE;