MODULE_DESCRIPTION("tftp NAT helper");
MODULE_LICENSE("GPL");
-#define MAX_PORTS 8
-
-static int ports[MAX_PORTS];
-static int ports_c = 0;
-module_param_array(ports, int, ports_c, 0400);
-MODULE_PARM_DESC(ports, "port numbers of tftp servers");
-
-#if 0
-#define DEBUGP(format, args...) printk("%s:%s:" format, \
- __FILE__, __FUNCTION__ , ## args)
-#else
-#define DEBUGP(format, args...)
-#endif
-static unsigned int
-tftp_nat_help(struct ip_conntrack *ct,
- struct ip_conntrack_expect *exp,
- struct ip_nat_info *info,
- enum ip_conntrack_info ctinfo,
- unsigned int hooknum,
- struct sk_buff **pskb)
+static unsigned int help(struct sk_buff **pskb,
+ enum ip_conntrack_info ctinfo,
+ struct ip_conntrack_expect *exp)
{
- int dir = CTINFO2DIR(ctinfo);
- struct tftphdr _tftph, *tfh;
- struct ip_conntrack_tuple repl;
-
- if (!((hooknum == NF_IP_POST_ROUTING && dir == IP_CT_DIR_ORIGINAL)
- || (hooknum == NF_IP_PRE_ROUTING && dir == IP_CT_DIR_REPLY)))
- return NF_ACCEPT;
-
- if (!exp) {
- DEBUGP("no conntrack expectation to modify\n");
- return NF_ACCEPT;
- }
-
- tfh = skb_header_pointer(*pskb,
- (*pskb)->nh.iph->ihl*4+sizeof(struct udphdr),
- sizeof(_tftph), &_tftph);
- if (tfh == NULL)
+ exp->saved_proto.udp.port = exp->tuple.dst.u.tcp.port;
+ exp->dir = IP_CT_DIR_REPLY;
+ exp->expectfn = ip_nat_follow_master;
+ if (ip_conntrack_expect_related(exp) != 0) {
+ ip_conntrack_expect_free(exp);
return NF_DROP;
-
- switch (ntohs(tfh->opcode)) {
- /* RRQ and WRQ works the same way */
- case TFTP_OPCODE_READ:
- case TFTP_OPCODE_WRITE:
- repl = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
- DEBUGP("");
- DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
- DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
- DEBUGP("expecting: ");
- DUMP_TUPLE(&repl);
- DUMP_TUPLE(&exp->mask);
- ip_conntrack_change_expect(exp, &repl);
- break;
- default:
- DEBUGP("Unknown opcode\n");
- }
-
- return NF_ACCEPT;
-}
-
-static unsigned int
-tftp_nat_expected(struct sk_buff **pskb,
- unsigned int hooknum,
- struct ip_conntrack *ct,
- struct ip_nat_info *info)
-{
- const struct ip_conntrack *master = ct->master->expectant;
- const struct ip_conntrack_tuple *orig =
- &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
- struct ip_nat_multi_range mr;
-#if 0
- const struct ip_conntrack_tuple *repl =
- &master->tuplehash[IP_CT_DIR_REPLY].tuple;
- struct udphdr _udph, *uh;
-
- uh = skb_header_pointer(*pskb,
- (*pskb)->nh.iph->ihl*4,
- sizeof(_udph), &_udph);
- if (uh == NULL)
- return NF_DROP;
-#endif
-
- IP_NF_ASSERT(info);
- IP_NF_ASSERT(master);
- IP_NF_ASSERT(!(info->initialized & (1 << HOOK2MANIP(hooknum))));
-
- mr.rangesize = 1;
- mr.range[0].flags = IP_NAT_RANGE_MAP_IPS;
-
- if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) {
- mr.range[0].min_ip = mr.range[0].max_ip = orig->dst.ip;
- DEBUGP("orig: %u.%u.%u.%u:%u <-> %u.%u.%u.%u:%u "
- "newsrc: %u.%u.%u.%u\n",
- NIPQUAD((*pskb)->nh.iph->saddr), ntohs(uh->source),
- NIPQUAD((*pskb)->nh.iph->daddr), ntohs(uh->dest),
- NIPQUAD(orig->dst.ip));
- } else {
- mr.range[0].min_ip = mr.range[0].max_ip = orig->src.ip;
- mr.range[0].min.udp.port = mr.range[0].max.udp.port =
- orig->src.u.udp.port;
- mr.range[0].flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
-
- DEBUGP("orig: %u.%u.%u.%u:%u <-> %u.%u.%u.%u:%u "
- "newdst: %u.%u.%u.%u:%u\n",
- NIPQUAD((*pskb)->nh.iph->saddr), ntohs(uh->source),
- NIPQUAD((*pskb)->nh.iph->daddr), ntohs(uh->dest),
- NIPQUAD(orig->src.ip), ntohs(orig->src.u.udp.port));
}
-
- return ip_nat_setup_info(ct,&mr,hooknum);
+ return NF_ACCEPT;
}
-static struct ip_nat_helper tftp[MAX_PORTS];
-static char tftp_names[MAX_PORTS][10];
-
-static void fini(void)
+static void __exit fini(void)
{
- int i;
-
- for (i = 0 ; i < ports_c; i++) {
- DEBUGP("unregistering helper for port %d\n", ports[i]);
- ip_nat_helper_unregister(&tftp[i]);
- }
+ ip_nat_tftp_hook = NULL;
+ /* Make sure noone calls it, meanwhile. */
+ synchronize_net();
}
static int __init init(void)
{
- int i, ret = 0;
- char *tmpname;
-
- if (ports_c == 0)
- ports[ports_c++] = TFTP_PORT;
-
- for (i = 0; i < ports_c; i++) {
- memset(&tftp[i], 0, sizeof(struct ip_nat_helper));
-
- tftp[i].tuple.dst.protonum = IPPROTO_UDP;
- tftp[i].tuple.src.u.udp.port = htons(ports[i]);
- tftp[i].mask.dst.protonum = 0xFFFF;
- tftp[i].mask.src.u.udp.port = 0xFFFF;
- tftp[i].help = tftp_nat_help;
- tftp[i].flags = 0;
- tftp[i].me = THIS_MODULE;
- tftp[i].expect = tftp_nat_expected;
-
- tmpname = &tftp_names[i][0];
- if (ports[i] == TFTP_PORT)
- sprintf(tmpname, "tftp");
- else
- sprintf(tmpname, "tftp-%d", i);
- tftp[i].name = tmpname;
-
- DEBUGP("ip_nat_tftp: registering for port %d: name %s\n",
- ports[i], tftp[i].name);
- ret = ip_nat_helper_register(&tftp[i]);
-
- if (ret) {
- printk("ip_nat_tftp: unable to register for port %d\n",
- ports[i]);
- fini();
- return ret;
- }
- }
- return ret;
+ BUG_ON(ip_nat_tftp_hook);
+ ip_nat_tftp_hook = help;
+ return 0;
}
module_init(init);
git://git.onelab.eu / linux-2.6.git / blobdiff