static inline unsigned int tse6_sack_adjust(struct sk_buff **pskb,
struct tcphdr *tcph,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned int thoff)
{
unsigned int dir, optoff, optend;
struct nf_conn_nat *nat = &ct->nat;
optoff = thoff + sizeof(struct tcphdr);
optend = thoff + tcph->doff*4;
if (!skb_make_writable(pskb, optend))
return 0;
dir = CTINFO2DIR(ctinfo);
while (optoff < optend) {
/* Usually: option, length. */
unsigned char *op = (*pskb)->data + optoff;
switch (op[0]) {
case TCPOPT_EOL:
return 1;
case TCPOPT_NOP:
optoff++;
continue;
default:
/* no partial options */
if (optoff + 1 == optend ||
optoff + op[1] > optend ||
op[1] < 2)
return 0;
if (op[0] == TCPOPT_SACK &&
op[1] >= 2+TCPOLEN_SACK_PERBLOCK &&
((op[1] - 2) % TCPOLEN_SACK_PERBLOCK) == 0)
sack_adjust(*pskb, tcph, optoff+2,
optoff+op[1],
&nat->info.seq[!dir]);
optoff += op[1];
}
}
return 1;
}
static inline unsigned int
nf_nat_sack_adjust(struct sk_buff *skb,
struct tcphdr *tcph,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo)
{
unsigned int dir, optoff, optend;
struct nf_conn_nat *nat = nfct_nat(ct);
optoff = ip_hdrlen(skb) + sizeof(struct tcphdr);
optend = ip_hdrlen(skb) + tcph->doff * 4;
if (!skb_make_writable(skb, optend))
return 0;
dir = CTINFO2DIR(ctinfo);
while (optoff < optend) {
unsigned char *op = skb->data + optoff;
switch (op[0]) {
case TCPOPT_EOL:
return 1;
case TCPOPT_NOP:
optoff++;
continue;
default:
if (optoff + 1 == optend ||
optoff + op[1] > optend ||
op[1] < 2)
return 0;
if (op[0] == TCPOPT_SACK &&
op[1] >= 2+TCPOLEN_SACK_PERBLOCK &&
((op[1] - 2) % TCPOLEN_SACK_PERBLOCK) == 0)
sack_adjust(skb, tcph, optoff+2,
optoff+op[1], &nat->seq[!dir]);
optoff += op[1];
}
}
return 1;
}