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[NETFILTER]: ipt_TCPMSS: reformat 

- fix whitespace error
- break lines at 80 characters
- reformat some expressions to be more readable

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2006-09-20 11:58:35 -07:00 committed by David S. Miller
parent 50b9f1d509
commit 68e1f188de
1 changed files with 31 additions and 27 deletions
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48
net/ipv4/netfilter/ipt_TCPMSS.c
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@ -31,8 +31,10 @@ static inline unsigned int
optlen(const u_int8_t *opt, unsigned int offset) optlen(const u_int8_t *opt, unsigned int offset)
{ {
/* Beware zero-length options: make finite progress */ /* Beware zero-length options: make finite progress */
if (opt[offset] <= TCPOPT_NOP || opt[offset+1] == 0) return 1; if (opt[offset] <= TCPOPT_NOP || opt[offset+1] == 0)
else return opt[offset+1]; return 1;
else
return opt[offset+1];
} }
static unsigned int static unsigned int
@ -55,7 +57,6 @@ ipt_tcpmss_target(struct sk_buff **pskb,
iph = (*pskb)->nh.iph; iph = (*pskb)->nh.iph;
tcplen = (*pskb)->len - iph->ihl*4; tcplen = (*pskb)->len - iph->ihl*4;
tcph = (void *)iph + iph->ihl*4; tcph = (void *)iph + iph->ihl*4;
/* Since it passed flags test in tcp match, we know it is is /* Since it passed flags test in tcp match, we know it is is
@ -74,33 +75,35 @@ ipt_tcpmss_target(struct sk_buff **pskb,
if (tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU) { if (tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU) {
if (!(*pskb)->dst) { if (!(*pskb)->dst) {
if (net_ratelimit()) if (net_ratelimit())
printk(KERN_ERR printk(KERN_ERR "ipt_tcpmss_target: "
"ipt_tcpmss_target: no dst?! can't determine path-MTU\n"); "no dst?! can't determine path-MTU\n");
return NF_DROP; /* or IPT_CONTINUE ?? */ return NF_DROP; /* or IPT_CONTINUE ?? */
} }
if(dst_mtu((*pskb)->dst) <= (sizeof(struct iphdr) + sizeof(struct tcphdr))) { if (dst_mtu((*pskb)->dst) <= sizeof(struct iphdr) +
sizeof(struct tcphdr)) {
if (net_ratelimit()) if (net_ratelimit())
printk(KERN_ERR printk(KERN_ERR "ipt_tcpmss_target: "
"ipt_tcpmss_target: unknown or invalid path-MTU (%d)\n", dst_mtu((*pskb)->dst)); "unknown or invalid path-MTU (%d)\n",
dst_mtu((*pskb)->dst));
return NF_DROP; /* or IPT_CONTINUE ?? */ return NF_DROP; /* or IPT_CONTINUE ?? */
} }
newmss = dst_mtu((*pskb)->dst) - sizeof(struct iphdr) - sizeof(struct tcphdr); newmss = dst_mtu((*pskb)->dst) - sizeof(struct iphdr) -
sizeof(struct tcphdr);
} else } else
newmss = tcpmssinfo->mss; newmss = tcpmssinfo->mss;
opt = (u_int8_t *)tcph; opt = (u_int8_t *)tcph;
for (i = sizeof(struct tcphdr); i < tcph->doff*4; i += optlen(opt, i)) { for (i = sizeof(struct tcphdr); i < tcph->doff*4; i += optlen(opt, i)) {
if ((opt[i] == TCPOPT_MSS) && if (opt[i] == TCPOPT_MSS && tcph->doff*4 - i >= TCPOLEN_MSS &&
((tcph->doff*4 - i) >= TCPOLEN_MSS) && opt[i+1] == TCPOLEN_MSS) {
(opt[i+1] == TCPOLEN_MSS)) {
u_int16_t oldmss; u_int16_t oldmss;
oldmss = (opt[i+2] << 8) | opt[i+3]; oldmss = (opt[i+2] << 8) | opt[i+3];
if((tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU) && if (tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU &&
(oldmss <= newmss)) oldmss <= newmss)
return IPT_CONTINUE; return IPT_CONTINUE;
opt[i+2] = (newmss & 0xff00) >> 8; opt[i+2] = (newmss & 0xff00) >> 8;
@ -193,9 +196,9 @@ static inline int find_syn_match(const struct ipt_entry_match *m)
{ {
const struct ipt_tcp *tcpinfo = (const struct ipt_tcp *)m->data; const struct ipt_tcp *tcpinfo = (const struct ipt_tcp *)m->data;
if (strcmp(m->u.kernel.match->name, "tcp") == 0 if (strcmp(m->u.kernel.match->name, "tcp") == 0 &&
&& (tcpinfo->flg_cmp & TH_SYN) tcpinfo->flg_cmp & TH_SYN &&
&& !(tcpinfo->invflags & IPT_TCP_INV_FLAGS)) !(tcpinfo->invflags & IPT_TCP_INV_FLAGS))
return 1; return 1;
return 0; return 0;
@ -212,11 +215,12 @@ ipt_tcpmss_checkentry(const char *tablename,
const struct ipt_tcpmss_info *tcpmssinfo = targinfo; const struct ipt_tcpmss_info *tcpmssinfo = targinfo;
const struct ipt_entry *e = e_void; const struct ipt_entry *e = e_void;
if((tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU) && if (tcpmssinfo->mss == IPT_TCPMSS_CLAMP_PMTU &&
((hook_mask & ~((1 << NF_IP_FORWARD) (hook_mask & ~((1 << NF_IP_FORWARD) |
| (1 << NF_IP_LOCAL_OUT) (1 << NF_IP_LOCAL_OUT) |
| (1 << NF_IP_POST_ROUTING))) != 0)) { (1 << NF_IP_POST_ROUTING))) != 0) {
printk("TCPMSS: path-MTU clamping only supported in FORWARD, OUTPUT and POSTROUTING hooks\n"); printk("TCPMSS: path-MTU clamping only supported in "
"FORWARD, OUTPUT and POSTROUTING hooks\n");
return 0; return 0;
} }