summaryrefslogtreecommitdiff
path: root/pfinet/linux-src/net/ipv4/ip_masq_vdolive.c
diff options
context:
space:
mode:
Diffstat (limited to 'pfinet/linux-src/net/ipv4/ip_masq_vdolive.c')
-rw-r--r--pfinet/linux-src/net/ipv4/ip_masq_vdolive.c294
1 files changed, 294 insertions, 0 deletions
diff --git a/pfinet/linux-src/net/ipv4/ip_masq_vdolive.c b/pfinet/linux-src/net/ipv4/ip_masq_vdolive.c
new file mode 100644
index 00000000..4724e3b9
--- /dev/null
+++ b/pfinet/linux-src/net/ipv4/ip_masq_vdolive.c
@@ -0,0 +1,294 @@
+/*
+ * IP_MASQ_VDOLIVE - VDO Live masquerading module
+ *
+ *
+ * Version: @(#)$Id: ip_masq_vdolive.c,v 1.4 1998/10/06 04:49:07 davem Exp $
+ *
+ * Author: Nigel Metheringham <Nigel.Metheringham@ThePLAnet.net>
+ * PLAnet Online Ltd
+ *
+ * Fixes: Minor changes for 2.1 by
+ * Steven Clarke <Steven.Clarke@ThePlanet.Net>, Planet Online Ltd
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Thanks:
+ * Thank you to VDOnet Corporation for allowing me access to
+ * a protocol description without an NDA. This means that
+ * this module can be distributed as source - a great help!
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <asm/system.h>
+#include <linux/skbuff.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/init.h>
+#include <net/protocol.h>
+#include <net/tcp.h>
+#include <net/ip_masq.h>
+
+struct vdolive_priv_data {
+ /* Ports used */
+ unsigned short origport;
+ unsigned short masqport;
+ /* State of decode */
+ unsigned short state;
+};
+
+/*
+ * List of ports (up to MAX_MASQ_APP_PORTS) to be handled by helper
+ * First port is set to the default port.
+ */
+static int ports[MAX_MASQ_APP_PORTS] = {7000}; /* I rely on the trailing items being set to zero */
+struct ip_masq_app *masq_incarnations[MAX_MASQ_APP_PORTS];
+
+/*
+ * Debug level
+ */
+#ifdef CONFIG_IP_MASQ_DEBUG
+static int debug=0;
+MODULE_PARM(debug, "i");
+#endif
+
+MODULE_PARM(ports, "1-" __MODULE_STRING(MAX_MASQ_APP_PORTS) "i");
+
+static int
+masq_vdolive_init_1 (struct ip_masq_app *mapp, struct ip_masq *ms)
+{
+ MOD_INC_USE_COUNT;
+ if ((ms->app_data = kmalloc(sizeof(struct vdolive_priv_data),
+ GFP_ATOMIC)) == NULL)
+ IP_MASQ_DEBUG(1-debug, "VDOlive: No memory for application data\n");
+ else
+ {
+ struct vdolive_priv_data *priv =
+ (struct vdolive_priv_data *)ms->app_data;
+ priv->origport = 0;
+ priv->masqport = 0;
+ priv->state = 0;
+ }
+ return 0;
+}
+
+static int
+masq_vdolive_done_1 (struct ip_masq_app *mapp, struct ip_masq *ms)
+{
+ MOD_DEC_USE_COUNT;
+ if (ms->app_data)
+ kfree_s(ms->app_data, sizeof(struct vdolive_priv_data));
+ return 0;
+}
+
+int
+masq_vdolive_out (struct ip_masq_app *mapp, struct ip_masq *ms, struct sk_buff **skb_p, __u32 maddr)
+{
+ struct sk_buff *skb;
+ struct iphdr *iph;
+ struct tcphdr *th;
+ char *data, *data_limit;
+ unsigned int tagval; /* This should be a 32 bit quantity */
+ struct ip_masq *n_ms;
+ struct vdolive_priv_data *priv =
+ (struct vdolive_priv_data *)ms->app_data;
+
+ /* This doesn't work at all if no priv data was allocated on startup */
+ if (!priv)
+ return 0;
+
+ /* Everything running correctly already */
+ if (priv->state == 3)
+ return 0;
+
+ skb = *skb_p;
+ iph = skb->nh.iph;
+ th = (struct tcphdr *)&(((char *)iph)[iph->ihl*4]);
+ data = (char *)&th[1];
+
+ data_limit = skb->h.raw + skb->len;
+
+ if (data+8 > data_limit) {
+ IP_MASQ_DEBUG(1-debug, "VDOlive: packet too short for ID %p %p\n", data, data_limit);
+ return 0;
+ }
+ memcpy(&tagval, data+4, 4);
+ IP_MASQ_DEBUG(1-debug, "VDOlive: packet seen, tag %ld, in initial state %d\n", ntohl(tagval), priv->state);
+
+ /* Check for leading packet ID */
+ if ((ntohl(tagval) != 6) && (ntohl(tagval) != 1)) {
+ IP_MASQ_DEBUG(1-debug, "VDOlive: unrecognised tag %ld, in initial state %d\n", ntohl(tagval), priv->state);
+ return 0;
+ }
+
+
+ /* Check packet is long enough for data - ignore if not */
+ if ((ntohl(tagval) == 6) && (data+36 > data_limit)) {
+ IP_MASQ_DEBUG(1-debug, "VDOlive: initial packet too short %p %p\n", data, data_limit);
+ return 0;
+ } else if ((ntohl(tagval) == 1) && (data+20 > data_limit)) {
+ IP_MASQ_DEBUG(1-debug,"VDOlive: secondary packet too short %p %p\n", data, data_limit);
+ return 0;
+ }
+
+ /* Adjust data pointers */
+ /*
+ * I could check the complete protocol version tag
+ * in here however I am just going to look for the
+ * "VDO Live" tag in the hope that this part will
+ * remain constant even if the version changes
+ */
+ if (ntohl(tagval) == 6) {
+ data += 24;
+ IP_MASQ_DEBUG(1-debug, "VDOlive: initial packet found\n");
+ } else {
+ data += 8;
+ IP_MASQ_DEBUG(1-debug, "VDOlive: secondary packet found\n");
+ }
+
+ if (memcmp(data, "VDO Live", 8) != 0) {
+ IP_MASQ_DEBUG(1-debug,"VDOlive: did not find tag\n");
+ return 0;
+ }
+ /*
+ * The port number is the next word after the tag.
+ * VDOlive encodes all of these values
+ * in 32 bit words, so in this case I am
+ * skipping the first 2 bytes of the next
+ * word to get to the relevant 16 bits
+ */
+ data += 10;
+
+ /*
+ * If we have not seen the port already,
+ * set the masquerading tunnel up
+ */
+ if (!priv->origport) {
+ memcpy(&priv->origport, data, 2);
+ IP_MASQ_DEBUG(1-debug, "VDOlive: found port %d\n", ntohs(priv->origport));
+
+ /* Open up a tunnel */
+ n_ms = ip_masq_new(IPPROTO_UDP,
+ maddr, 0,
+ ms->saddr, priv->origport,
+ ms->daddr, 0,
+ IP_MASQ_F_NO_DPORT);
+
+ if (n_ms==NULL) {
+ ip_masq_put(n_ms);
+ IP_MASQ_DEBUG(1-debug, "VDOlive: unable to build UDP tunnel for %x:%x\n", ms->saddr, priv->origport);
+ /* Leave state as unset */
+ priv->origport = 0;
+ return 0;
+ }
+ ip_masq_listen(n_ms);
+
+ ip_masq_put(ms);
+ priv->masqport = n_ms->mport;
+ } else if (memcmp(data, &(priv->origport), 2)) {
+ IP_MASQ_DEBUG(1-debug, "VDOlive: ports do not match\n");
+ /* Write the port in anyhow!!! */
+ }
+
+ /*
+ * Write masq port into packet
+ */
+ memcpy(data, &(priv->masqport), 2);
+ IP_MASQ_DEBUG(1-debug, "VDOlive: rewrote port %d to %d, server %08X\n", ntohs(priv->origport), ntohs(priv->masqport), ms->saddr);
+
+ /*
+ * Set state bit to make which bit has been done
+ */
+
+ priv->state |= (ntohl(tagval) == 6) ? 1 : 2;
+
+ return 0;
+}
+
+
+struct ip_masq_app ip_masq_vdolive = {
+ NULL, /* next */
+ "VDOlive", /* name */
+ 0, /* type */
+ 0, /* n_attach */
+ masq_vdolive_init_1, /* ip_masq_init_1 */
+ masq_vdolive_done_1, /* ip_masq_done_1 */
+ masq_vdolive_out, /* pkt_out */
+ NULL /* pkt_in */
+};
+
+/*
+ * ip_masq_vdolive initialization
+ */
+
+__initfunc(int ip_masq_vdolive_init(void))
+{
+ int i, j;
+
+ for (i=0; (i<MAX_MASQ_APP_PORTS); i++) {
+ if (ports[i]) {
+ if ((masq_incarnations[i] = kmalloc(sizeof(struct ip_masq_app),
+ GFP_KERNEL)) == NULL)
+ return -ENOMEM;
+ memcpy(masq_incarnations[i], &ip_masq_vdolive, sizeof(struct ip_masq_app));
+ if ((j = register_ip_masq_app(masq_incarnations[i],
+ IPPROTO_TCP,
+ ports[i]))) {
+ return j;
+ }
+ IP_MASQ_DEBUG(1-debug, "RealAudio: loaded support on port[%d] = %d\n", i, ports[i]);
+ } else {
+ /* To be safe, force the incarnation table entry to NULL */
+ masq_incarnations[i] = NULL;
+ }
+ }
+ return 0;
+}
+
+/*
+ * ip_masq_vdolive fin.
+ */
+
+int ip_masq_vdolive_done(void)
+{
+ int i, j, k;
+
+ k=0;
+ for (i=0; (i<MAX_MASQ_APP_PORTS); i++) {
+ if (masq_incarnations[i]) {
+ if ((j = unregister_ip_masq_app(masq_incarnations[i]))) {
+ k = j;
+ } else {
+ kfree(masq_incarnations[i]);
+ masq_incarnations[i] = NULL;
+ IP_MASQ_DEBUG(1-debug,"VDOlive: unloaded support on port[%d] = %d\n", i, ports[i]);
+ }
+ }
+ }
+ return k;
+}
+
+
+#ifdef MODULE
+EXPORT_NO_SYMBOLS;
+
+int init_module(void)
+{
+ if (ip_masq_vdolive_init() != 0)
+ return -EIO;
+ return 0;
+}
+
+void cleanup_module(void)
+{
+ if (ip_masq_vdolive_done() != 0)
+ IP_MASQ_DEBUG(1-debug, "ip_masq_vdolive: can't remove module");
+}
+
+#endif /* MODULE */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 15:41:01 +0000