static inline int
help_out(struct sk_buff *skb, unsigned char *rb_ptr, unsigned int datalen,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
struct ip_ct_rtsp_expect expinfo;
int dir = CTINFO2DIR(ctinfo); /* = IP_CT_DIR_ORIGINAL */
//struct tcphdr* tcph = (void*)iph + iph->ihl * 4;
//uint tcplen = pktlen - iph->ihl * 4;
char* pdata = rb_ptr;
//uint datalen = tcplen - tcph->doff * 4;
uint dataoff = 0;
int ret = NF_ACCEPT;
struct nf_conntrack_expect *exp;
__be16 be_loport;
typeof(nf_nat_rtsp_hook) nf_nat_rtsp;
memset(&expinfo, 0, sizeof(expinfo));
while (dataoff < datalen) {
uint cmdoff = dataoff;
uint hdrsoff = 0;
uint hdrslen = 0;
uint cseqoff = 0;
uint cseqlen = 0;
uint transoff = 0;
uint translen = 0;
uint off;
if (!rtsp_parse_message(pdata, datalen, &dataoff,
&hdrsoff, &hdrslen,
&cseqoff, &cseqlen,
&transoff, &translen))
break; /* not a valid message */
if (strncmp(pdata+cmdoff, "SETUP ", 6) != 0)
continue; /* not a SETUP message */
pr_debug("found a setup message\n");
off = 0;
if(translen) {
rtsp_parse_transport(pdata+transoff, translen, &expinfo);
}
if (expinfo.loport == 0) {
pr_debug("no udp transports found\n");
continue; /* no udp transports found */
}
pr_debug("udp transport found, ports=(%d,%hu,%hu)\n",
(int)expinfo.pbtype, expinfo.loport, expinfo.hiport);
exp = nf_ct_expect_alloc(ct);
if (!exp) {
ret = NF_DROP;
goto out;
}
be_loport = htons(expinfo.loport);
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
/* media stream source can be different from the RTSP server address */
// &ct->tuplehash[!dir].tuple.src.u3, &ct->tuplehash[!dir].tuple.dst.u3,
NULL, &ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_UDP, NULL, &be_loport);
exp->master = ct;
exp->expectfn = expected;
exp->flags = 0;
if (expinfo.pbtype == pb_range) {
pr_debug("Changing expectation mask to handle multiple ports\n");
//exp->mask.dst.u.udp.port = 0xfffe;
}
pr_debug("expect_related %pI4:%u-%pI4:%u\n",
&exp->tuple.src.u3.ip,
ntohs(exp->tuple.src.u.udp.port),
&exp->tuple.dst.u3.ip,
ntohs(exp->tuple.dst.u.udp.port));
nf_nat_rtsp = rcu_dereference(nf_nat_rtsp_hook);
if (nf_nat_rtsp && ct->status & IPS_NAT_MASK)
/* pass the request off to the nat helper */
ret = nf_nat_rtsp(skb, ctinfo, hdrsoff, hdrslen, &expinfo, exp);
else if (nf_ct_expect_related(exp) != 0) {
pr_info("nf_conntrack_expect_related failed\n");
ret = NF_DROP;
}
nf_ct_expect_put(exp);
goto out;
}
out:
return ret;
}
static inline int
help_out(struct sk_buff **pskb, unsigned char *rb_ptr, unsigned int datalen,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
struct ip_ct_rtsp_expect expinfo;
int dir = CTINFO2DIR(ctinfo); /* = IP_CT_DIR_ORIGINAL */
//struct tcphdr* tcph = (void*)iph + iph->ihl * 4;
//uint tcplen = pktlen - iph->ihl * 4;
char* pdata = rb_ptr;
//uint datalen = tcplen - tcph->doff * 4;
uint dataoff = 0;
int ret = NF_ACCEPT;
struct nf_conntrack_expect *exp;
__be16 be_loport;
typeof(nf_nat_rtsp_hook) nf_nat_rtsp;
memset(&expinfo, 0, sizeof(expinfo));
while (dataoff < datalen) {
uint cmdoff = dataoff;
uint hdrsoff = 0;
uint hdrslen = 0;
uint cseqoff = 0;
uint cseqlen = 0;
uint transoff = 0;
uint translen = 0;
uint off;
if (!rtsp_parse_message(pdata, datalen, &dataoff,
&hdrsoff, &hdrslen,
&cseqoff, &cseqlen,
&transoff, &translen))
break; /* not a valid message */
if (strncmp(pdata+cmdoff, "SETUP ", 6) != 0)
continue; /* not a SETUP message */
pr_debug("found a setup message\n");
off = 0;
if(translen) {
rtsp_parse_transport(pdata+transoff, translen, &expinfo);
}
if (expinfo.loport == 0) {
pr_debug("no udp transports found\n");
continue; /* no udp transports found */
}
pr_debug("udp transport found, ports=(%d,%hu,%hu)\n",
(int)expinfo.pbtype, expinfo.loport, expinfo.hiport);
exp = nf_conntrack_expect_alloc(ct);
if (!exp) {
ret = NF_DROP;
goto out;
}
be_loport = htons(expinfo.loport);
/*
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&ct->tuplehash[!dir].tuple.src.u3, &ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_UDP, NULL, &be_loport);
¸øexp¸³Öµ */
exp->tuple.dst.u3 = ct->tuplehash[!dir].tuple.dst.u3;
exp->tuple.src.u3 = ct->tuplehash[!dir].tuple.src.u3;
exp->tuple.src.l3num = ct->tuplehash[dir].tuple.src.l3num;
exp->tuple.src.u.udp.port = 0;
exp->tuple.dst.u.udp.port = be_loport;
exp->tuple.dst.protonum = IPPROTO_UDP;
exp->mask = (struct nf_conntrack_tuple)
{ .src = { .l3num = 0xFFFF,
.u = { .udp = { 0 }},
},
.dst = { .protonum = 0xFF,
.u = { .udp = { __constant_htons(0xFFFF) }},
},
};
if (ct->tuplehash[dir].tuple.src.l3num == PF_INET) {
exp->mask.src.u3.ip = htonl(0xFFFFFFFF);
exp->mask.dst.u3.ip = htonl(0xFFFFFFFF);
} else {
memset(exp->mask.src.u3.ip6, 0xFF,
sizeof(exp->mask.src.u3.ip6));
memset(exp->mask.dst.u3.ip6, 0xFF,
sizeof(exp->mask.src.u3.ip6));
}
// exp->master = ct;
exp->helper = NULL;
exp->flags = 0;
if (expinfo.pbtype == pb_range) {
pr_debug("Changing expectation mask to handle multiple ports\n");
//exp->mask.dst.u.udp.port = 0xfffe;
}
pr_debug("expect_related %u.%u.%u.%u:%u-%u.%u.%u.%u:%u\n",
NIPQUAD(exp->tuple.src.u3.ip),
ntohs(exp->tuple.src.u.udp.port),
NIPQUAD(exp->tuple.dst.u3.ip),
ntohs(exp->tuple.dst.u.udp.port));
nf_nat_rtsp = rcu_dereference(nf_nat_rtsp_hook);
if (nf_nat_rtsp && ct->status & IPS_NAT_MASK)
/* pass the request off to the nat helper */
ret = nf_nat_rtsp(pskb, ctinfo, hdrsoff, hdrslen, &expinfo, exp);
else if (nf_conntrack_expect_related(exp) != 0) {
pr_info("nf_conntrack_expect_related failed\n");
ret = NF_DROP;
}
nf_conntrack_expect_put(exp);
goto out;
}
