static unsigned int mangle_sdp(struct sk_buff **pskb,
enum ip_conntrack_info ctinfo,
struct ip_conntrack *ct,
u_int32_t newip, u_int16_t port,
const char *dptr)
{
char buffer[sizeof("nnn.nnn.nnn.nnn")];
unsigned int dataoff, bufflen;
dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
/* Mangle owner and contact info. */
bufflen = sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip));
if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_OWNER]))
return 0;
if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_CONNECTION]))
return 0;
/* Mangle media port. */
bufflen = sprintf(buffer, "%u", port);
if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_MEDIA]))
return 0;
return mangle_content_len(pskb, ctinfo, ct, dptr);
}
static unsigned int mangle_sdp(struct sk_buff *skb,
enum ip_conntrack_info ctinfo,
struct nf_conn *ct,
__be32 newip, u_int16_t port,
const char *dptr)
{
char buffer[sizeof("nnn.nnn.nnn.nnn")];
unsigned int dataoff, bufflen;
dataoff = ip_hdrlen(skb) + sizeof(struct udphdr);
/* Mangle owner and contact info. */
bufflen = sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip));
if (!mangle_sip_packet(skb, ctinfo, ct, &dptr, skb->len - dataoff,
buffer, bufflen, POS_OWNER_IP4))
return 0;
if (!mangle_sip_packet(skb, ctinfo, ct, &dptr, skb->len - dataoff,
buffer, bufflen, POS_CONNECTION_IP4))
return 0;
/* Mangle media port. */
bufflen = sprintf(buffer, "%u", port);
if (!mangle_sip_packet(skb, ctinfo, ct, &dptr, skb->len - dataoff,
buffer, bufflen, POS_MEDIA))
return 0;
return mangle_content_len(skb, ctinfo, ct, dptr);
}
static unsigned int ip_nat_sip(struct sk_buff **pskb,
enum ip_conntrack_info ctinfo,
struct ip_conntrack *ct,
const char **dptr)
{
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];
unsigned int bufflen, dataoff;
u_int32_t ip;
u_int16_t port;
dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
ip = ct->tuplehash[!dir].tuple.dst.ip;
port = ct->tuplehash[!dir].tuple.dst.u.udp.port;
bufflen = sprintf(buffer, "%u.%u.%u.%u:%u", NIPQUAD(ip), ntohs(port));
/* short packet ? */
if (((*pskb)->len - dataoff) < (sizeof("SIP/2.0") - 1))
return 0;
/* Basic rules: requests and responses. */
if (memcmp(*dptr, "SIP/2.0", sizeof("SIP/2.0") - 1) == 0) {
const char *aux;
if ((ctinfo) < IP_CT_IS_REPLY) {
mangle_sip_packet(pskb, ctinfo, ct, dptr,
(*pskb)->len - dataoff,
buffer, bufflen,
&ct_sip_hdrs[POS_CONTACT]);
return 1;
}
if (!mangle_sip_packet(pskb, ctinfo, ct, dptr,
(*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_VIA]))
return 0;
/* This search should ignore case, but later.. */
aux = ct_sip_search("CSeq:", *dptr, sizeof("CSeq:") - 1,
(*pskb)->len - dataoff);
if (!aux)
return 0;
if (!ct_sip_search("REGISTER", aux, sizeof("REGISTER"),
ct_sip_lnlen(aux, *dptr + (*pskb)->len - dataoff)))
return 1;
return mangle_sip_packet(pskb, ctinfo, ct, dptr,
(*pskb)->len - dataoff,
buffer, bufflen,
&ct_sip_hdrs[POS_CONTACT]);
}
if ((ctinfo) < IP_CT_IS_REPLY) {
if (!mangle_sip_packet(pskb, ctinfo, ct, dptr,
(*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_VIA]))
return 0;
/* Mangle Contact if exists only. - watch udp_nat_mangle()! */
mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
buffer, bufflen, &ct_sip_hdrs[POS_CONTACT]);
return 1;
}
/* This mangle requests headers. */
return mangle_sip_packet(pskb, ctinfo, ct, dptr,
ct_sip_lnlen(*dptr,
*dptr + (*pskb)->len - dataoff),
buffer, bufflen, &ct_sip_hdrs[POS_REQ_HEADER]);
}