URL
https://opencores.org/ocsvn/or1k/or1k/trunk
Subversion Repositories or1k
[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [net/] [ipv4/] [ip_masq_vdolive.c] - Rev 1772
Go to most recent revision | Compare with Previous | Blame | View Log
/* * IP_MASQ_VDOLIVE - VDO Live masquerading module * * * Version: @(#)$Id: ip_masq_vdolive.c,v 1.1 2005-12-20 10:41:09 jcastillo Exp $ * * Author: Nigel Metheringham <Nigel.Metheringham@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/module.h> #include <asm/system.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/skbuff.h> #include <linux/in.h> #include <linux/ip.h> #include <net/protocol.h> #include <net/tcp.h> #include <net/ip_masq.h> #ifndef DEBUG_CONFIG_IP_MASQ_VDOLIVE #define DEBUG_CONFIG_IP_MASQ_VDOLIVE 0 #endif struct vdolive_priv_data { /* Ports used */ unsigned short origport; unsigned short masqport; /* State of decode */ unsigned short state; }; #ifdef MODULE #define STATIC #else #define STATIC static #endif /* * 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]; 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) printk(KERN_INFO "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, struct device *dev) { 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->h.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) { #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: packet too short for ID %lx %lx\n", data, data_limit); #endif return 0; } memcpy(&tagval, data+4, 4); #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: packet seen, tag %ld, in initial state %d\n", ntohl(tagval), priv->state); #endif /* Check for leading packet ID */ if ((ntohl(tagval) != 6) && (ntohl(tagval) != 1)) { #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: unrecognised tag %ld, in initial state %d\n", ntohl(tagval), priv->state); #endif return 0; } /* Check packet is long enough for data - ignore if not */ if ((ntohl(tagval) == 6) && (data+36 > data_limit)) { #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: initial packet too short %lx %lx\n", data, data_limit); #endif return 0; } else if ((ntohl(tagval) == 1) && (data+20 > data_limit)) { #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: secondary packet too short %lx %lx\n", data, data_limit); #endif 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; #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: initial packet found\n"); #endif } else { data += 8; #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: secondary packet found\n"); #endif } if (memcmp(data, "VDO Live", 8) != 0) { #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: did not find tag\n"); #endif 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); #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: found port %d\n", ntohs(priv->origport)); #endif /* Open up a tunnel */ n_ms = ip_masq_new(dev, IPPROTO_UDP, ms->saddr, priv->origport, ms->daddr, 0, IP_MASQ_F_NO_DPORT); if (n_ms==NULL) { printk("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_set_expire(n_ms, ip_masq_expire->udp_timeout); priv->masqport = n_ms->mport; } else if (memcmp(data, &(priv->origport), 2)) { printk("VDOlive: ports do not match\n"); /* Write the port in anyhow!!! */ } /* * Write masq port into packet */ memcpy(data, &(priv->masqport), 2); #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: rewrote port %d to %d, server %s\n", ntohs(priv->origport), ntohs(priv->masqport), in_ntoa(ms->saddr)); #endif /* * 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 */ 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; } #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("RealAudio: loaded support on port[%d] = %d\n", i, ports[i]); #endif } 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; #if DEBUG_CONFIG_IP_MASQ_VDOLIVE printk("VDOlive: unloaded support on port[%d] = %d\n", i, ports[i]); #endif } } } return k; } #ifdef MODULE int init_module(void) { if (ip_masq_vdolive_init() != 0) return -EIO; register_symtab(0); return 0; } void cleanup_module(void) { if (ip_masq_vdolive_done() != 0) printk("ip_masq_vdolive: can't remove module"); } #endif /* MODULE */
Go to most recent revision | Compare with Previous | Blame | View Log