static int tftp_help(struct sk_buff *skb,
unsigned int protoff,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo)
{
const struct tftphdr *tfh;
struct tftphdr _tftph;
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
unsigned int ret = NF_ACCEPT;
typeof(nf_nat_tftp_hook) nf_nat_tftp;
#ifdef CONFIG_CAMEO_ALG_TFTP
if(!tftp_enable)
return NF_ACCEPT;
#endif
tfh = skb_header_pointer(skb, protoff + sizeof(struct udphdr),
sizeof(_tftph), &_tftph);
if (tfh == NULL)
return NF_ACCEPT;
switch (ntohs(tfh->opcode)) {
case TFTP_OPCODE_READ:
case TFTP_OPCODE_WRITE:
/* RRQ and WRQ works the same way */
nf_ct_dump_tuple(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
nf_ct_dump_tuple(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
exp = nf_ct_expect_alloc(ct);
if (exp == NULL)
return NF_DROP;
tuple = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
nf_ct_l3num(ct),
&tuple->src.u3, &tuple->dst.u3,
IPPROTO_UDP, NULL, &tuple->dst.u.udp.port);
pr_debug("expect: ");
nf_ct_dump_tuple(&exp->tuple);
nf_nat_tftp = rcu_dereference(nf_nat_tftp_hook);
if (nf_nat_tftp && ct->status & IPS_NAT_MASK)
ret = nf_nat_tftp(skb, ctinfo, exp);
else if (nf_ct_expect_related(exp) != 0)
ret = NF_DROP;
nf_ct_expect_put(exp);
break;
case TFTP_OPCODE_DATA:
case TFTP_OPCODE_ACK:
pr_debug("Data/ACK opcode\n");
break;
case TFTP_OPCODE_ERROR:
pr_debug("Error opcode\n");
break;
default:
pr_debug("Unknown opcode\n");
}
return ret;
}
static int expect_q931(struct sk_buff *skb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
int i;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
typeof(nat_q931_hook) nat_q931;
#ifdef CONFIG_HTC_NETWORK_MODIFY
if (IS_ERR(info) || (!info))
printk(KERN_ERR "[NET] info is NULL in %s!\n", __func__);
#endif
for (i = 0; i < count; i++) {
if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
sizeof(addr)) == 0 && port != 0)
break;
}
if (i >= count)
return 0;
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
gkrouted_only ?
&ct->tuplehash[!dir].tuple.src.u3 : NULL,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_TCP, NULL, &port);
exp->helper = nf_conntrack_helper_q931;
exp->flags = NF_CT_EXPECT_PERMANENT;
nat_q931 = rcu_dereference(nat_q931_hook);
if (nat_q931 && ct->status & IPS_NAT_MASK) {
ret = nat_q931(skb, ct, ctinfo, data, taddr, i, port, exp);
} else {
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_ras: expect Q.931 ");
nf_ct_dump_tuple(&exp->tuple);
info->sig_port[dir] = port;
} else
ret = -1;
}
nf_ct_expect_put(exp);
return ret;
}
static int expect_callforwarding(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
typeof(nat_callforwarding_hook) nat_callforwarding;
if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
return 0;
if (callforward_filter &&
callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
nf_ct_l3num(ct))) {
pr_debug("nf_ct_q931: Call Forwarding not tracked\n");
return 0;
}
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->helper = nf_conntrack_helper_q931;
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
ct->status & IPS_NAT_MASK) {
ret = nat_callforwarding(skb, ct, ctinfo, data, dataoff,
taddr, port, exp);
} else {
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_q931: expect Call Forwarding ");
nf_ct_dump_tuple(&exp->tuple);
} else
ret = -1;
}
nf_ct_expect_put(exp);
return ret;
}
static int expect_t120(struct sk_buff *skb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
typeof(nat_t120_hook) nat_t120;
if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
port == 0)
return 0;
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
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_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT;
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_t120 = rcu_dereference(nat_t120_hook)) &&
ct->status & IPS_NAT_MASK) {
ret = nat_t120(skb, ct, ctinfo, data, dataoff, taddr,
port, exp);
} else {
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_h323: expect T.120 ");
nf_ct_dump_tuple(&exp->tuple);
} else
ret = -1;
}
nf_ct_expect_put(exp);
return ret;
}
static int process_acf(struct sk_buff *skb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, AdmissionConfirm *acf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
typeof(set_sig_addr_hook) set_sig_addr;
pr_debug("nf_ct_ras: ACF\n");
if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
&addr, &port))
return 0;
if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
set_sig_addr = rcu_dereference(set_sig_addr_hook);
if (set_sig_addr && ct->status & IPS_NAT_MASK)
return set_sig_addr(skb, ct, ctinfo, data,
&acf->destCallSignalAddress, 1);
return 0;
}
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT;
exp->helper = nf_conntrack_helper_q931;
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_ras: expect Q.931 ");
nf_ct_dump_tuple(&exp->tuple);
} else
ret = -1;
nf_ct_expect_put(exp);
return ret;
}
static int process_gcf(struct sk_buff *skb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, GatekeeperConfirm *gcf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
pr_debug("nf_ct_ras: GCF\n");
if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
return 0;
if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
port == ct->tuplehash[dir].tuple.src.u.udp.port)
return 0;
if (test_bit(IPS_EXPECTED_BIT, &ct->status))
return 0;
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_UDP, NULL, &port);
exp->helper = nf_conntrack_helper_ras;
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_ras: expect RAS ");
nf_ct_dump_tuple(&exp->tuple);
} else
ret = -1;
nf_ct_expect_put(exp);
return ret;
}
static int process_lcf(struct sk_buff *skb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, LocationConfirm *lcf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_inet_addr addr;
struct nf_conntrack_expect *exp;
pr_debug("nf_ct_ras: LCF\n");
if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
&addr, &port))
return 0;
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT;
exp->helper = nf_conntrack_helper_q931;
if (nf_ct_expect_related(exp) == 0) {
pr_debug("nf_ct_ras: expect Q.931 ");
nf_ct_dump_tuple(&exp->tuple);
} else
ret = -1;
nf_ct_expect_put(exp);
return ret;
}
/* expect GRE connections (PNS->PAC and PAC->PNS direction) */
static int exp_gre(struct nf_conn *ct, __be16 callid, __be16 peer_callid)
{
struct nf_conntrack_expect *exp_orig, *exp_reply;
enum ip_conntrack_dir dir;
int ret = 1;
typeof(nf_nat_pptp_hook_exp_gre) nf_nat_pptp_exp_gre;
exp_orig = nf_ct_expect_alloc(ct);
if (exp_orig == NULL)
goto out;
exp_reply = nf_ct_expect_alloc(ct);
if (exp_reply == NULL)
goto out_put_orig;
/* original direction, PNS->PAC */
dir = IP_CT_DIR_ORIGINAL;
nf_ct_expect_init(exp_orig, NF_CT_EXPECT_CLASS_DEFAULT,
nf_ct_l3num(ct),
&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[dir].tuple.dst.u3,
IPPROTO_GRE, &peer_callid, &callid);
exp_orig->expectfn = pptp_expectfn;
/* reply direction, PAC->PNS */
dir = IP_CT_DIR_REPLY;
nf_ct_expect_init(exp_reply, NF_CT_EXPECT_CLASS_DEFAULT,
nf_ct_l3num(ct),
&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[dir].tuple.dst.u3,
IPPROTO_GRE, &callid, &peer_callid);
exp_reply->expectfn = pptp_expectfn;
nf_nat_pptp_exp_gre = rcu_dereference(nf_nat_pptp_hook_exp_gre);
if (nf_nat_pptp_exp_gre && ct->status & IPS_NAT_MASK)
nf_nat_pptp_exp_gre(exp_orig, exp_reply);
if (nf_ct_expect_related(exp_orig) != 0)
goto out_put_both;
if (nf_ct_expect_related(exp_reply) != 0)
goto out_unexpect_orig;
/* Add GRE keymap entries */
if (nf_ct_gre_keymap_add(ct, IP_CT_DIR_ORIGINAL, &exp_orig->tuple) != 0)
goto out_unexpect_both;
if (nf_ct_gre_keymap_add(ct, IP_CT_DIR_REPLY, &exp_reply->tuple) != 0) {
nf_ct_gre_keymap_destroy(ct);
goto out_unexpect_both;
}
ret = 0;
out_put_both:
nf_ct_expect_put(exp_reply);
out_put_orig:
nf_ct_expect_put(exp_orig);
out:
return ret;
out_unexpect_both:
nf_ct_unexpect_related(exp_reply);
out_unexpect_orig:
nf_ct_unexpect_related(exp_orig);
goto out_put_both;
}
static int help(struct sk_buff *skb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
unsigned int dataoff;
const struct iphdr *iph;
const struct tcphdr *th;
struct tcphdr _tcph;
const char *data_limit;
char *data, *ib_ptr;
int dir = CTINFO2DIR(ctinfo);
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
__be32 dcc_ip;
u_int16_t dcc_port;
__be16 port;
int i, ret = NF_ACCEPT;
char *addr_beg_p, *addr_end_p;
typeof(nf_nat_irc_hook) nf_nat_irc;
/* If packet is coming from IRC server */
if (dir == IP_CT_DIR_REPLY)
return NF_ACCEPT;
/* Until there's been traffic both ways, don't look in packets. */
if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
return NF_ACCEPT;
/* Not a full tcp header? */
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
if (th == NULL)
return NF_ACCEPT;
/* No data? */
dataoff = protoff + th->doff*4;
if (dataoff >= skb->len)
return NF_ACCEPT;
spin_lock_bh(&irc_buffer_lock);
ib_ptr = skb_header_pointer(skb, dataoff, skb->len - dataoff,
irc_buffer);
BUG_ON(ib_ptr == NULL);
data = ib_ptr;
data_limit = ib_ptr + skb->len - dataoff;
/* strlen("\1DCC SENT t AAAAAAAA P\1\n")=24
* 5+MINMATCHLEN+strlen("t AAAAAAAA P\1\n")=14 */
while (data < data_limit - (19 + MINMATCHLEN)) {
if (memcmp(data, "\1DCC ", 5)) {
data++;
continue;
}
data += 5;
/* we have at least (19+MINMATCHLEN)-5 bytes valid data left */
iph = ip_hdr(skb);
pr_debug("DCC found in master %pI4:%u %pI4:%u\n",
&iph->saddr, ntohs(th->source),
&iph->daddr, ntohs(th->dest));
for (i = 0; i < ARRAY_SIZE(dccprotos); i++) {
if (memcmp(data, dccprotos[i], strlen(dccprotos[i]))) {
/* no match */
continue;
}
data += strlen(dccprotos[i]);
pr_debug("DCC %s detected\n", dccprotos[i]);
/* we have at least
* (19+MINMATCHLEN)-5-dccprotos[i].matchlen bytes valid
* data left (== 14/13 bytes) */
if (parse_dcc(data, data_limit, &dcc_ip,
&dcc_port, &addr_beg_p, &addr_end_p)) {
pr_debug("unable to parse dcc command\n");
continue;
}
pr_debug("DCC bound ip/port: %pI4:%u\n",
&dcc_ip, dcc_port);
/* dcc_ip can be the internal OR external (NAT'ed) IP */
tuple = &ct->tuplehash[dir].tuple;
if (tuple->src.u3.ip != dcc_ip &&
tuple->dst.u3.ip != dcc_ip) {
net_warn_ratelimited("Forged DCC command from %pI4: %pI4:%u\n",
&tuple->src.u3.ip,
&dcc_ip, dcc_port);
continue;
}
exp = nf_ct_expect_alloc(ct);
if (exp == NULL) {
nf_ct_helper_log(skb, ct,
"cannot alloc expectation");
ret = NF_DROP;
goto out;
}
tuple = &ct->tuplehash[!dir].tuple;
port = htons(dcc_port);
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
tuple->src.l3num,
NULL, &tuple->dst.u3,
IPPROTO_TCP, NULL, &port);
nf_nat_irc = rcu_dereference(nf_nat_irc_hook);
if (nf_nat_irc && ct->status & IPS_NAT_MASK)
ret = nf_nat_irc(skb, ctinfo, protoff,
addr_beg_p - ib_ptr,
addr_end_p - addr_beg_p,
exp);
else if (nf_ct_expect_related(exp) != 0) {
nf_ct_helper_log(skb, ct,
"cannot add expectation");
ret = NF_DROP;
}
nf_ct_expect_put(exp);
goto out;
}
}
out:
spin_unlock_bh(&irc_buffer_lock);
return ret;
}
static int help(struct sk_buff *skb,
unsigned int protoff,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo)
{
unsigned int dataoff, datalen;
const struct tcphdr *th;
struct tcphdr _tcph;
void *sb_ptr;
int ret = NF_ACCEPT;
int dir = CTINFO2DIR(ctinfo);
struct nf_ct_sane_master *ct_sane_info;
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
struct sane_request *req;
struct sane_reply_net_start *reply;
ct_sane_info = &nfct_help(ct)->help.ct_sane_info;
/* Until there's been traffic both ways, don't look in packets. */
if (ctinfo != IP_CT_ESTABLISHED &&
ctinfo != IP_CT_ESTABLISHED+IP_CT_IS_REPLY)
return NF_ACCEPT;
/* Not a full tcp header? */
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
if (th == NULL)
return NF_ACCEPT;
/* No data? */
dataoff = protoff + th->doff * 4;
if (dataoff >= skb->len)
return NF_ACCEPT;
datalen = skb->len - dataoff;
spin_lock_bh(&nf_sane_lock);
sb_ptr = skb_header_pointer(skb, dataoff, datalen, sane_buffer);
BUG_ON(sb_ptr == NULL);
if (dir == IP_CT_DIR_ORIGINAL) {
if (datalen != sizeof(struct sane_request))
goto out;
req = sb_ptr;
if (req->RPC_code != htonl(SANE_NET_START)) {
/* Not an interesting command */
ct_sane_info->state = SANE_STATE_NORMAL;
goto out;
}
/* We're interested in the next reply */
ct_sane_info->state = SANE_STATE_START_REQUESTED;
goto out;
}
/* Is it a reply to an uninteresting command? */
if (ct_sane_info->state != SANE_STATE_START_REQUESTED)
goto out;
/* It's a reply to SANE_NET_START. */
ct_sane_info->state = SANE_STATE_NORMAL;
if (datalen < sizeof(struct sane_reply_net_start)) {
pr_debug("nf_ct_sane: NET_START reply too short\n");
goto out;
}
reply = sb_ptr;
if (reply->status != htonl(SANE_STATUS_SUCCESS)) {
/* saned refused the command */
pr_debug("nf_ct_sane: unsuccessful SANE_STATUS = %u\n",
ntohl(reply->status));
goto out;
}
/* Invalid saned reply? Ignore it. */
if (reply->zero != 0)
goto out;
exp = nf_ct_expect_alloc(ct);
if (exp == NULL) {
ret = NF_DROP;
goto out;
}
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&tuple->src.u3, &tuple->dst.u3,
IPPROTO_TCP, NULL, &reply->port);
pr_debug("nf_ct_sane: expect: ");
nf_ct_dump_tuple(&exp->tuple);
/* Can't expect this? Best to drop packet now. */
if (nf_ct_expect_related(exp) != 0)
ret = NF_DROP;
nf_ct_expect_put(exp);
out:
spin_unlock_bh(&nf_sane_lock);
return ret;
}
static int help(struct sk_buff *skb,
unsigned int protoff,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo)
{
unsigned int dataoff, datalen;
const struct tcphdr *th;
struct tcphdr _tcph;
void *sb_ptr;
int ret = NF_ACCEPT;
int dir = CTINFO2DIR(ctinfo);
struct nf_ct_sane_master *ct_sane_info;
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
struct sane_request *req;
struct sane_reply_net_start *reply;
ct_sane_info = &nfct_help(ct)->help.ct_sane_info;
if (ctinfo != IP_CT_ESTABLISHED &&
ctinfo != IP_CT_ESTABLISHED+IP_CT_IS_REPLY)
return NF_ACCEPT;
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
if (th == NULL)
return NF_ACCEPT;
dataoff = protoff + th->doff * 4;
if (dataoff >= skb->len)
return NF_ACCEPT;
datalen = skb->len - dataoff;
spin_lock_bh(&nf_sane_lock);
sb_ptr = skb_header_pointer(skb, dataoff, datalen, sane_buffer);
BUG_ON(sb_ptr == NULL);
if (dir == IP_CT_DIR_ORIGINAL) {
if (datalen != sizeof(struct sane_request))
goto out;
req = sb_ptr;
if (req->RPC_code != htonl(SANE_NET_START)) {
ct_sane_info->state = SANE_STATE_NORMAL;
goto out;
}
ct_sane_info->state = SANE_STATE_START_REQUESTED;
goto out;
}
if (ct_sane_info->state != SANE_STATE_START_REQUESTED)
goto out;
ct_sane_info->state = SANE_STATE_NORMAL;
if (datalen < sizeof(struct sane_reply_net_start)) {
pr_debug("nf_ct_sane: NET_START reply too short\n");
goto out;
}
reply = sb_ptr;
if (reply->status != htonl(SANE_STATUS_SUCCESS)) {
pr_debug("nf_ct_sane: unsuccessful SANE_STATUS = %u\n",
ntohl(reply->status));
goto out;
}
if (reply->zero != 0)
goto out;
exp = nf_ct_expect_alloc(ct);
if (exp == NULL) {
ret = NF_DROP;
goto out;
}
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
&tuple->src.u3, &tuple->dst.u3,
IPPROTO_TCP, NULL, &reply->port);
pr_debug("nf_ct_sane: expect: ");
nf_ct_dump_tuple(&exp->tuple);
if (nf_ct_expect_related(exp) != 0)
ret = NF_DROP;
nf_ct_expect_put(exp);
out:
spin_unlock_bh(&nf_sane_lock);
return ret;
}
static int help(struct sk_buff *skb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
unsigned int dataoff;
const struct iphdr *iph;
const struct tcphdr *th;
struct tcphdr _tcph;
const char *data_limit;
char *data, *ib_ptr;
int dir = CTINFO2DIR(ctinfo);
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
__be32 dcc_ip;
u_int16_t dcc_port;
__be16 port;
int i, ret = NF_ACCEPT;
char *addr_beg_p, *addr_end_p;
typeof(nf_nat_irc_hook) nf_nat_irc;
if (dir == IP_CT_DIR_REPLY)
return NF_ACCEPT;
if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
return NF_ACCEPT;
th = skb_header_pointer(skb, protoff, sizeof(_tcph), &_tcph);
if (th == NULL)
return NF_ACCEPT;
dataoff = protoff + th->doff*4;
if (dataoff >= skb->len)
return NF_ACCEPT;
spin_lock_bh(&irc_buffer_lock);
ib_ptr = skb_header_pointer(skb, dataoff, skb->len - dataoff,
irc_buffer);
BUG_ON(ib_ptr == NULL);
data = ib_ptr;
data_limit = ib_ptr + skb->len - dataoff;
while (data < data_limit - (19 + MINMATCHLEN)) {
if (memcmp(data, "\1DCC ", 5)) {
data++;
continue;
}
data += 5;
iph = ip_hdr(skb);
pr_debug("DCC found in master %pI4:%u %pI4:%u\n",
&iph->saddr, ntohs(th->source),
&iph->daddr, ntohs(th->dest));
for (i = 0; i < ARRAY_SIZE(dccprotos); i++) {
if (memcmp(data, dccprotos[i], strlen(dccprotos[i]))) {
continue;
}
data += strlen(dccprotos[i]);
pr_debug("DCC %s detected\n", dccprotos[i]);
if (parse_dcc(data, data_limit, &dcc_ip,
&dcc_port, &addr_beg_p, &addr_end_p)) {
pr_debug("unable to parse dcc command\n");
continue;
}
pr_debug("DCC bound ip/port: %pI4:%u\n",
&dcc_ip, dcc_port);
tuple = &ct->tuplehash[dir].tuple;
if (tuple->src.u3.ip != dcc_ip &&
tuple->dst.u3.ip != dcc_ip) {
if (net_ratelimit())
printk(KERN_WARNING
"Forged DCC command from %pI4: %pI4:%u\n",
&tuple->src.u3.ip,
&dcc_ip, dcc_port);
continue;
}
exp = nf_ct_expect_alloc(ct);
if (exp == NULL) {
ret = NF_DROP;
goto out;
}
tuple = &ct->tuplehash[!dir].tuple;
port = htons(dcc_port);
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
tuple->src.l3num,
NULL, &tuple->dst.u3,
IPPROTO_TCP, NULL, &port);
nf_nat_irc = rcu_dereference(nf_nat_irc_hook);
if (nf_nat_irc && ct->status & IPS_NAT_MASK)
ret = nf_nat_irc(skb, ctinfo,
addr_beg_p - ib_ptr,
addr_end_p - addr_beg_p,
exp);
else if (nf_ct_expect_related(exp) != 0)
ret = NF_DROP;
nf_ct_expect_put(exp);
goto out;
}
}
out:
spin_unlock_bh(&irc_buffer_lock);
return ret;
}
static int expect_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
__be16 rtp_port, rtcp_port;
union nf_inet_addr addr;
struct nf_conntrack_expect *rtp_exp;
struct nf_conntrack_expect *rtcp_exp;
typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
port == 0)
return 0;
port &= htons(~1);
rtp_port = port;
rtcp_port = htons(ntohs(port) + 1);
if ((rtp_exp = nf_ct_expect_alloc(ct)) == NULL)
return -1;
nf_ct_expect_init(rtp_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, &rtp_port);
if ((rtcp_exp = nf_ct_expect_alloc(ct)) == NULL) {
nf_ct_expect_put(rtp_exp);
return -1;
}
nf_ct_expect_init(rtcp_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, &rtcp_port);
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
ct->status & IPS_NAT_MASK) {
ret = nat_rtp_rtcp(skb, ct, ctinfo, data, dataoff,
taddr, port, rtp_port, rtp_exp, rtcp_exp);
} else {
if (nf_ct_expect_related(rtp_exp) == 0) {
if (nf_ct_expect_related(rtcp_exp) == 0) {
pr_debug("nf_ct_h323: expect RTP ");
nf_ct_dump_tuple(&rtp_exp->tuple);
pr_debug("nf_ct_h323: expect RTCP ");
nf_ct_dump_tuple(&rtcp_exp->tuple);
} else {
nf_ct_unexpect_related(rtp_exp);
ret = -1;
}
} else
ret = -1;
}
nf_ct_expect_put(rtp_exp);
nf_ct_expect_put(rtcp_exp);
return ret;
}
static int
cone_nat_help(struct sk_buff *skb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
int dir = CTINFO2DIR(ctinfo);
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple *tuple;
union nf_inet_addr *src_addr = NULL;
__be16 *src_port = NULL;
int ret = NF_ACCEPT;
if (ctinfo == IP_CT_ESTABLISHED || dir != IP_CT_DIR_ORIGINAL)
return NF_ACCEPT;
pr_debug("skb[%p] ctinfo[%d] dir[%d]\n", skb, ctinfo, dir);
pr_debug("packet[%d bytes] "
"%pI4:%hu->%pI4:%hu, "
"reply: %pI4:%hu->%pI4:%hu\n",
skb->len,
&(ct->tuplehash[dir].tuple.src.u3.ip),
ntohs(ct->tuplehash[dir].tuple.src.u.udp.port),
&(ct->tuplehash[dir].tuple.dst.u3.ip),
ntohs(ct->tuplehash[dir].tuple.dst.u.udp.port),
&(ct->tuplehash[!dir].tuple.src.u3.ip),
ntohs(ct->tuplehash[!dir].tuple.src.u.udp.port),
&(ct->tuplehash[!dir].tuple.dst.u3.ip),
ntohs(ct->tuplehash[!dir].tuple.dst.u.udp.port));
/* Create expect */
if ((exp = nf_ct_expect_alloc(ct)) == NULL)
return NF_ACCEPT;
/*
IP_CT_DIR_REPLY
0 - symmetric nat
1 - full, *:* -> natip:natport -> lanip:lanport
2 - restricted, wanip:* -> natip:natport -> lanip:lanport
3 - port restricted, wanip:wanport -> natip:natport -> lanip:lanport
*/
tuple = &ct->tuplehash[!dir].tuple;
switch (conenat_type)
{
case 1:
src_addr = NULL;
src_port = NULL;
break;
case 2:
src_addr = &tuple->src.u3;
src_port = NULL;
break;
case 3:
src_addr = &tuple->src.u3;
src_port = &tuple->src.u.udp.port;
break;
default:
src_addr = NULL;
src_port = NULL;
break;
}
nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
nf_ct_l3num(ct),
src_addr, &tuple->dst.u3,
tuple->dst.protonum,
src_port, &tuple->dst.u.udp.port);
exp->dir = !dir;
exp->flags = NF_CT_EXPECT_PERMANENT;
exp->saved_ip = ct->tuplehash[dir].tuple.src.u3.ip;
exp->saved_proto = ct->tuplehash[dir].tuple.src.u;
exp->expectfn = cone_nat_expect;
pr_debug("save %pI4:%hu, ",
&exp->saved_ip, ntohs(exp->saved_proto.udp.port));
nf_ct_dump_tuple(&exp->tuple);
/* Setup expect */
ret = nf_ct_expect_related(exp);
nf_ct_expect_put(exp);
if (ret == 0)
{
pr_debug("expect setup, skb=%p, ret=%d.\n", skb, ret);
}
else
{
pr_debug("expect setup failed.\n");
}
return NF_ACCEPT;
}
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;
}
