酷!學園

Dear All:
            看了andrew的討論版後發覺有問題的人還一直沒有得到解答,我也不想跑太遠,這樣摟誰將study-area的新竹點搞定,並安排實做課程,我提供一個月2天免費教學好了,將我所學與學員分享摟,來來來embedded 入門,進階,深入 來這裡學拉。

新竹也需要有人推廣linux阿...小弟願意幫忙推廣當新竹的聯絡窗口...需要一些協助請跟我連絡...xlinux_huang@hotmail.com

哈哈解了不再用upnp這方法了剛剛測試完成確定都ok快來跟網友報告;
--- sip-conntrack-nat/linux-2.4.30/include/linux/netfilter_ipv4/ip_conntrack_sip.h   (revision 0)
+++ sip-conntrack-nat/linux-2.4.30/include/linux/netfilter_ipv4/ip_conntrack_sip.h   (revision 0)
@@ -0,0 +1,75 @@
+#ifndef __IP_CONNTRACK_SIP_H__
+#define __IP_CONNTRACK_SIP_H__
+/* SIP tracking. */
+
+#ifdef __KERNEL__
+
+#define SIP_PORT   5060
+#define SIP_TIMEOUT   3600
+
+#define POS_VIA      0
+#define POS_CONTACT   1
+#define   POS_CONTENT   2
+#define POS_MEDIA   3
+#define POS_OWNER   4
+#define POS_CONECTION   5
+#define POS_REQ_HEADER   6
+#define POS_SDP_HEADER   7
+
+struct sip_header_nfo {
+   const char *lname;
+   size_t lnlen;
+   const char *sname;
+   size_t snlen;
+   const char *ln_str;
+   size_t ln_strlen;
+   int (*match_len)(const char *, const char *, int *);
+
+};
+
+extern unsigned int (*ip_nat_sip_hook)(struct sk_buff **pskb,
+            enum ip_conntrack_info ctinfo,
+            struct ip_conntrack *ct,
+            char **dptr);
+            
+/* For NAT to hook in when on expect. */
+extern unsigned int (*ip_nat_sdp_hook)(struct sk_buff **pskb,
+            enum ip_conntrack_info ctinfo,
+            struct ip_conntrack_expect *exp,
+            char *dptr);
+
+extern int ct_sip_get_info(char *dptr, int dlen, int *matchoff,
+            int *matchlen, struct sip_header_nfo *hnfo);
+
+/* get line lenght until first CR or LF seen. */
+static __inline__ int ct_sip_lnlen(char *line, char *limit)
+{
+        char *k = line;
+
+        while ((line <= limit) && (*line == '\r' || *line == '\n'))
+                line++;
+
+        while (line <= limit) {
+                if (*line == '\r' || *line == '\n')
+                        break;
+                line++;
+        }
+        return line - k;
+}
+
+/* Linear string search, case sensitive. */
+static __inline__ char *ct_sip_search(const char *needle, char *haystack,
+            int needle_len, int haystack_len)
+{
+   char *limit = haystack + (haystack_len - needle_len);
+
+   while (haystack <= limit) {
+      if (memcmp(haystack, needle, needle_len) == 0)
+         return haystack;
+      haystack++;
+   }
+   return NULL;
+}
+#endif /* __KERNEL__ */
+
+#endif /* __IP_CONNTRACK_SIP_H__ */
Index: sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Makefile.ladd
===================================================================
--- sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Makefile.ladd   (revision 0)
+++ sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Makefile.ladd   (revision 0)
@@ -0,0 +1,6 @@
+obj-$(CONFIG_IP_NF_CONNTRACK) += ip_conntrack.o
+
+# SIP support
+obj-$(CONFIG_IP_NF_SIP) += ip_conntrack_sip.o
+obj-$(CONFIG_IP_NF_NAT_SIP) += ip_nat_sip.o
+
Index: sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Kconfig.ladd
===================================================================
--- sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Kconfig.ladd   (revision 0)
+++ sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/Kconfig.ladd   (revision 0)
@@ -0,0 +1,18 @@
+config IP_NF_NAT_SIP
+   tristate
+   depends on IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
+   default IP_NF_NAT if IP_NF_SIP=y
+   default m if IP_NF_SIP=m
+
+config IP_NF_SIP
+   tristate  'SIP support'
+   depends on IP_NF_CONNTRACK
+   help
+     SIP is an application-layer control protocol that can establish,
+        modify, and terminate multimedia sessions (conferences) such as
+        Internet telephony calls. With the ip_conntrack_sip and
+     the ip_nat_sip modules you can support the protocol on a connection
+     tracking/NATing firewall.
+   
+     If you want to compile it as a module, say 'M' here and read
+     Documentation/modules.txt.  If unsure, say 'N'.
Index: sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_conntrack_sip.c
===================================================================
--- sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_conntrack_sip.c   (revision 0)
+++ sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_conntrack_sip.c   (revision 0)
@@ -0,0 +1,405 @@
+/* SIP extension for IP connection tracking.
+ *
+ * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
+ * based on RR's ip_conntrack_ftp.c and other modules.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/netfilter.h>
+#include <linux/ip.h>
+#include <linux/ctype.h>
+#include <net/checksum.h>
+#include <net/udp.h>
+
+#include <linux/netfilter_ipv4/lockhelp.h>
+#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
+#include <linux/netfilter_ipv4/ip_conntrack_sip.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>");
+MODULE_DESCRIPTION("SIP connection tracking helper");
+
+static DECLARE_LOCK(sipbf_lock);
+
+#define MAX_PORTS   8
+static int ports[MAX_PORTS];
+static int ports_c;
+module_param_array(ports, int, &ports_c, 0400);
+MODULE_PARM_DESC(ports, " port numbers of sip servers");
+
+static unsigned int sip_timeout = SIP_TIMEOUT;
+
+module_param(sip_timeout, int, 0600);
+MODULE_PARM_DESC(sip_timeout, "timeout for the master sip session");
+
+unsigned int (*ip_nat_sip_hook)(struct sk_buff **pskb,
+            enum ip_conntrack_info ctinfo,
+            struct ip_conntrack *ct,
+            char **dptr);
+EXPORT_SYMBOL_GPL(ip_nat_sip_hook);
+            
+unsigned int (*ip_nat_sdp_hook)(struct sk_buff **pskb,
+            enum ip_conntrack_info ctinfo,
+            struct ip_conntrack_expect *exp,
+            char *dptr);
+EXPORT_SYMBOL_GPL(ip_nat_sdp_hook);
+
+int ct_sip_get_info(char *dptr, int dlen, int *matchoff, int *matchlen,
+            struct sip_header_nfo *hnfo);
+
+EXPORT_SYMBOL(ct_sip_get_info);
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(format, args...)
+#endif
+
+static int digits_len(const char *dptr, const char *limit, int *shift);
+static int epaddr_len(const char *dptr, const char *limit, int *shift);
+static int skp_digits_len(const char *dptr, const char *limit, int *shift);
+static int skp_epaddr_len(const char *dptr, const char *limit, int *shift);
+
+struct sip_header_nfo ct_sip_hdrs[] = {
+   {    /* Via header */
+      "Via:",      sizeof("Via:") - 1,
+      "\r\nv:",   sizeof("\r\nv:") - 1, /* rfc3261 says "end in CRLF" */
+      "UDP ",    sizeof("UDP ") - 1,
+      epaddr_len
+   },
+   {    /* Contact header */
+      "Contact:",   sizeof("Contact:") - 1,
+      "\r\nm:",   sizeof("\r\nm:") - 1,
+      "sip:",      sizeof("sip:") - 1,
+      skp_epaddr_len
+   },
+   {    /* Content length header */
+      "Content-Length:", sizeof("Content-Length:") - 1,
+      "\r\nl:",   sizeof("\r\nl:") - 1,
+      ":",      sizeof(":") - 1,
+      skp_digits_len
+   },
+   {   /* SDP media info */
+      "\nm=",      sizeof("\nm=") - 1,   
+      "\rm=",      sizeof("\rm=") - 1,
+      "audio ",   sizeof("audio ") - 1,
+      digits_len
+   },
+   {    /* SDP owner address*/   
+      "\no=",      sizeof("\no=") - 1,
+      "\ro=",      sizeof("\ro=") - 1,
+      "IN IP4 ",   sizeof("IN IP4 ") - 1,
+      epaddr_len
+   },
+   {    /* SDP connection info */
+      "\nc=",      sizeof("\nc=") - 1,
+      "\rc=",      sizeof("\rc=") - 1,
+      "IN IP4 ",   sizeof("IN IP4 ") - 1,
+      epaddr_len
+   },
+   {    /* Requests headers */
+      "sip:",      sizeof("sip:") - 1,
+      "sip:",      sizeof("sip:") - 1, /* yes, i know.. */
+      "@",       sizeof("@") - 1,
+      epaddr_len
+   },
+   {    /* SDP version header */
+      "\nv=",      sizeof("\nv=") - 1,
+      "\rv=",      sizeof("\rv=") - 1,
+      "=",       sizeof("=") - 1,
+      digits_len
+   }
+};
+EXPORT_SYMBOL(ct_sip_hdrs);
+
+
+static int digits_len(const char *dptr, const char *limit, int *shift)
+{
+   int len = 0;   
+   while (dptr <= limit && isdigit(*dptr)) {
+      dptr++;
+      len++;
+   }
+   return len;
+}
+
+/* get digits lenght, skiping blank spaces. */
+static int skp_digits_len(const char *dptr, const char *limit, int *shift)
+{
+   for (; dptr <= limit && *dptr == ' '; dptr++)
+      (*shift)++;
+      
+   return digits_len(dptr, limit, shift);
+}
+
+/* Simple ipaddr parser.. */
+static int parse_ipaddr(const char *cp, char **endp,
+         uint32_t *ipaddr, const char *limit)
+{
+   unsigned long int val;
+   int i, digit = 0;
+   
+   for (i = 0, *ipaddr = 0; cp <= limit && i < 4; i++) {
+      digit = 0;
+      if (!isdigit(*cp))
+         break;
+      
+      val = simple_strtoul(cp, (char **)&cp, 10);
+      if (val > 0xFF)
+         return -1;
+   
+      ((uint8_t *)ipaddr) = val;   
+      digit = 1;
+   
+      if (*cp != '.')
+         break;
+      cp++;
+   }
+   if (!digit)
+      return -1;
+   
+   if (endp)
+      *endp = (char *)cp;
+
+   return 0;
+}
+
+/* skip ip address. returns it lenght. */
+static int epaddr_len(const char *dptr, const char *limit, int *shift)
+{
+   const char *aux = dptr;
+   uint32_t ip;
+   
+   if (parse_ipaddr(dptr, (char **)&dptr, &ip, limit) < 0) {
+      DEBUGP("ip: %s parse failed.!\n", dptr);
+      return 0;
+   }
+
+   /* Port number */
+   if (*dptr == ':') {
+      dptr++;
+      dptr += digits_len(dptr, limit, shift);
+   }
+   return dptr - aux;
+}
+
+/* get address lenght, skiping user info. */
+static int skp_epaddr_len(const char *dptr, const char *limit, int *shift)
+{
+   for (; dptr <= limit && *dptr != '@'; dptr++)
+         (*shift)++;   
+   
+   if (*dptr == '@') {
+      dptr++;
+      (*shift)++;
+      return epaddr_len(dptr, limit, shift);
+   }   
+   return  0;
+}
+
+/* Returns 0 if not found, -1 error parsing. */
+int ct_sip_get_info(char *dptr, int dlen,
+      int *matchoff, int *matchlen,
+      struct sip_header_nfo *hnfo)
+{
+   char *limit = dptr + (dlen - hnfo->lnlen);
+   char *aux, *k = dptr;
+   int shift = 0;
+
+   while (dptr <= limit) {
+      if ((strncmp(dptr, hnfo->lname, hnfo->lnlen) != 0) &&
+         (strncmp(dptr, hnfo->sname, hnfo->snlen) != 0))
+      {
+         dptr++;
+         continue;
+      }
+      aux = ct_sip_search(hnfo->ln_str, dptr, hnfo->ln_strlen,
+                  ct_sip_lnlen(dptr, limit));
+      if (!aux) {
+         DEBUGP("'%s' not found in '%s'.\n", hnfo->ln_str, hnfo->lname);
+         return -1;
+      }
+      aux += hnfo->ln_strlen;
+      
+      *matchlen = hnfo->match_len(aux, limit, &shift);
+      if (!*matchlen)
+         return -1;
+
+      *matchoff = (aux - k) + shift;
+      
+      DEBUGP("%s match succeeded! - len: %u\n", hnfo->lname, *matchlen);
+      return 1;
+   }
+   DEBUGP("%s header not found.\n", hnfo->lname);
+   return 0;
+}
+
+static int set_expected_rtp(struct sk_buff **pskb,
+         struct ip_conntrack *ct,
+         enum ip_conntrack_info ctinfo,
+         uint32_t ipaddr, uint16_t port,
+         char *dptr)
+{
+   struct ip_conntrack_expect *exp;
+   
+   exp = ip_conntrack_expect_alloc();
+   if (exp == NULL)
+      return NF_DROP;
+
+   exp->tuple = ((struct ip_conntrack_tuple)
+      { { ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip, { 0 } },
+        { ipaddr, { .udp = { htons(port) } }, IPPROTO_UDP }});
+        
+   exp->mask = ((struct ip_conntrack_tuple)
+      { { 0xFFFFFFFF, { 0 } },
+        { 0xFFFFFFFF, { .udp = { 0xFFFF } }, 0xFF }});
+
+   exp->expectfn = NULL;
+   exp->master = ct;
+   
+   if (ip_nat_sdp_hook)
+      return ip_nat_sdp_hook(pskb, ctinfo, exp, dptr);
+   else if (ip_conntrack_expect_related(exp) != 0) {
+      ip_conntrack_expect_free(exp);
+      return NF_DROP;
+   }
+   return NF_ACCEPT;
+}
+
+static int sip_help(struct sk_buff **pskb,
+         struct ip_conntrack *ct,
+         enum ip_conntrack_info ctinfo)
+{
+   unsigned int dataoff, datalen;
+   char *dptr;
+   int ret = NF_ACCEPT;
+   int matchoff, matchlen;
+   uint32_t ipaddr;
+   uint16_t port;
+   
+   /* No Data ? */
+   dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
+   if (dataoff >= (*pskb)->len) {
+      DEBUGP("skb->len = %u\n", (*pskb)->len);
+      return NF_ACCEPT;
+        }
+        
+   ip_ct_refresh_acct(ct, ctinfo, NULL, sip_timeout * HZ);
+      
+   LOCK_BH(&sipbf_lock);
+   
+   if ((dataoff + (*pskb)->len - dataoff) <= skb_headlen(*pskb))
+      dptr = (*pskb)->data + dataoff;
+   else {
+      DEBUGP("SIP mangle in copied skbuff not supported yet.\n");
+      goto out;
+   }
+   
+   if (ip_nat_sip_hook) {
+      if (!ip_nat_sip_hook(pskb, ctinfo, ct, &dptr)) {
+         ret = NF_DROP;
+         goto out;
+      }
+   }
+   
+   if ((ctinfo) >= IP_CT_IS_REPLY)
+      goto out;
+
+   /* After this point NAT, could have mangled skb, so
+      we need to recalculate payload lenght. */
+   datalen = (*pskb)->len - dataoff;
+
+   if (datalen < (sizeof("SIP/2.0 200") - 1))
+      goto out;
+   
+   /* RTP info only in some SDP pkts */
+   if (memcmp(dptr, "INVITE", sizeof("INVITE") - 1) != 0 &&
+       memcmp(dptr, "SIP/2.0 200", sizeof("SIP/2.0 200") - 1) != 0) {
+      goto out;
+   }
+   /* Get ip and port address from SDP packet. */
+   if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
+       &ct_sip_hdrs[POS_CONECTION]) > 0) {
+
+      /* We'll drop only if there are parse problems. */
+      if (parse_ipaddr(dptr + matchoff, NULL, &ipaddr,
+          dptr + datalen) < 0) {
+         ret = NF_DROP;
+         goto out;
+      }
+      if (ct_sip_get_info(dptr, datalen, &matchoff, &matchlen,
+          &ct_sip_hdrs[POS_MEDIA]) > 0) {
+
+         port = simple_strtoul(dptr + matchoff, NULL, 10);
+         if (port < 1024) {
+            ret = NF_DROP;
+            goto out;
+         }
+         ret = set_expected_rtp(pskb, ct, ctinfo,
+                  ipaddr, port, dptr);
+      }
+   }
+out:   UNLOCK_BH(&sipbf_lock);
+   return ret;
+}
+
+static struct ip_conntrack_helper sip[MAX_PORTS];
+static char sip_names[MAX_PORTS][10];
+
+static void fini(void)
+{
+   int i = 0;
+   for (; i < ports_c; i++) {
+      DEBUGP("unregistering helper for port %d\n", ports);
+      ip_conntrack_helper_unregister(&sip);
+   }
+}
+
+static int __init init(void)
+{
+   int i, ret;
+   char *tmpname;
+
+   if (ports_c == 0)
+      ports[ports_c++] = SIP_PORT;
+
+   for (i = 0; i < ports_c; i++) {
+      /* Create helper structure */
+      memset(&sip, 0, sizeof(struct ip_conntrack_helper));
+
+      sip.tuple.dst.protonum = IPPROTO_UDP;
+      sip.tuple.src.u.udp.port = htons(ports);
+      sip.mask.src.u.udp.port = 0xFFFF;
+      sip.mask.dst.protonum = 0xFF;
+      sip.max_expected = 1;
+      sip.timeout = 3 * 60; /* 3 minutes */
+      sip.me = THIS_MODULE;
+      sip.help = sip_help;
+
+      tmpname = &sip_names[0];
+      if (ports == SIP_PORT)
+         sprintf(tmpname, "sip");
+      else
+         sprintf(tmpname, "sip-%d", i);
+      sip.name = tmpname;
+
+      DEBUGP("port #%d: %d\n", i, ports);
+
+      ret=ip_conntrack_helper_register(&sip);
+      if (ret) {
+         printk("ERROR registering helper for port %d\n",
+            ports);
+         fini();
+         return(ret);
+      }
+   }
+   return(0);
+}
+
+module_init(init);
+module_exit(fini);
Index: sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_nat_sip.c
===================================================================
--- sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_nat_sip.c   (revision 0)
+++ sip-conntrack-nat/linux-2.4.30/net/ipv4/netfilter/ip_nat_sip.c   (revision 0)
@@ -0,0 +1,253 @@
+/* SIP extension for UDP NAT alteration.
+ *
+ * (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
+ * based on RR's ip_nat_ftp.c and other modules.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <linux/moduleparam.h>
+#include <net/udp.h>
+#include <linux/netfilter_ipv4/ip_nat.h>
+#include <linux/netfilter_ipv4/ip_nat_helper.h>
+#include <linux/netfilter_ipv4/ip_nat_rule.h>
+#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
+#include <linux/netfilter_ipv4/ip_conntrack_sip.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Christian Hentschel <chentschel@arnet.com.ar>");
+MODULE_DESCRIPTION("SIP NAT helper");
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(format, args...)
+#endif
+
+extern struct sip_header_nfo ct_sip_hdrs[];
+
+static unsigned int mangle_sip_packet(struct sk_buff **pskb,
+         enum ip_conntrack_info ctinfo,
+         struct ip_conntrack *ct,
+         char **dptr, int dlen,
+         char *buffer, int bufflen,
+         struct sip_header_nfo *hnfo)
+{
+   unsigned int matchlen, matchoff;
+   
+   if (ct_sip_get_info(*dptr, dlen, &matchoff, &matchlen, hnfo) <= 0)
+      return 0;
+
+   if (!ip_nat_mangle_udp_packet(pskb, ct, ctinfo,
+       matchoff, matchlen, buffer, bufflen)) {
+      return 0;
+   }
+   /* We need to reload this. Thanks Patrick. */
+   *dptr = (*pskb)->data + (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
+   return 1;
+}
+
+static unsigned int ip_nat_sip(struct sk_buff **pskb,
+         enum ip_conntrack_info ctinfo,
+         struct ip_conntrack *ct,
+         char **dptr)
+{
+   char buffer[sizeof("nnn.nnn.nnn.nnn:nnnnn")];   
+   unsigned int bufflen, dataoff;
+   uint32_t ip;
+   uint16_t port;
+   
+   dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
+   
+   if ((ctinfo) >= IP_CT_IS_REPLY) {
+      ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
+      port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port;
+   } else {
+      ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
+      port = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.udp.port;
+   }
+   bufflen = sprintf(buffer, "%u.%u.%u.%u:%u", NIPQUAD(ip), ntohs(port));
+   
+   /* short packet ? */
+   if (((*pskb)->len - dataoff) < (sizeof("SIP/2.0") - 1))
+      return 0;
+   
+   /* Basic rules: requests and responses. */
+   if (memcmp(*dptr, "SIP/2.0", sizeof("SIP/2.0") - 1) == 0) {
+   
+      if ((ctinfo) < IP_CT_IS_REPLY) {
+         mangle_sip_packet(pskb, ctinfo, ct, dptr,
+            (*pskb)->len - dataoff, buffer, bufflen,
+            &ct_sip_hdrs[POS_CONTACT]);
+         return 1;
+      }
+
+      if (!mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
+          buffer, bufflen, &ct_sip_hdrs[POS_VIA])) {
+         return 0;
+      }
+      
+      /* This search should ignore case, but later.. */
+      char *aux = ct_sip_search("CSeq:", *dptr, sizeof("CSeq:") - 1,
+                  (*pskb)->len - dataoff);
+      if (!aux)
+         return 0;
+      
+      if (!ct_sip_search("REGISTER", aux, sizeof("REGISTER"),
+          ct_sip_lnlen(aux, *dptr + (*pskb)->len - dataoff))) {
+         return 1;
+      }
+      return mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
+                  buffer, bufflen, &ct_sip_hdrs[POS_CONTACT]);
+   }
+   if ((ctinfo) < IP_CT_IS_REPLY) {
+      if (!mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
+          buffer, bufflen, &ct_sip_hdrs[POS_VIA])) {
+         return 0;
+      }
+      
+      /* Mangle Contact if exists only. - watch udp_nat_mangle()! */
+      mangle_sip_packet(pskb, ctinfo, ct, dptr, (*pskb)->len - dataoff,
+                  buffer, bufflen, &ct_sip_hdrs[POS_CONTACT]);
+      return 1;
+   }
+   /* This mangle requests headers. */
+   return mangle_sip_packet(pskb, ctinfo, ct, dptr,
+         ct_sip_lnlen(*dptr, *dptr + (*pskb)->len - dataoff),
+         buffer, bufflen, &ct_sip_hdrs[POS_REQ_HEADER]);
+}
+
+static int mangle_content_len(struct sk_buff **pskb,
+         enum ip_conntrack_info ctinfo,
+         struct ip_conntrack *ct,
+         char *dptr)
+{
+   unsigned int dataoff, matchoff, matchlen;
+   char buffer[sizeof("65536")];
+   int bufflen;
+   
+   dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
+   
+   /* Get actual SDP lenght */
+   if (ct_sip_get_info(dptr, (*pskb)->len - dataoff, &matchoff,
+       &matchlen, &ct_sip_hdrs[POS_SDP_HEADER]) > 0) {
+      
+      /* since ct_sip_get_info() give us a pointer passing 'v='
+         we need to add 2 bytes in this count. */
+      int c_len = (*pskb)->len - dataoff - matchoff + 2;
+      
+      /* Now, update SDP lenght */
+      if (ct_sip_get_info(dptr, (*pskb)->len - dataoff, &matchoff,
+          &matchlen, &ct_sip_hdrs[POS_CONTENT]) > 0) {
+
+         bufflen = sprintf(buffer, "%u", c_len);
+      
+         return ip_nat_mangle_udp_packet(pskb, ct, ctinfo, matchoff,
+                     matchlen, buffer, bufflen);
+      }
+   }
+   return 0;
+}
+
+static unsigned int mangle_sdp(struct sk_buff **pskb,
+         enum ip_conntrack_info ctinfo,
+         struct ip_conntrack *ct,
+         uint32_t newip, uint16_t port,
+         char *dptr)
+{
+   char buffer[sizeof("nnn.nnn.nnn.nnn")];
+   unsigned int dataoff, bufflen;
+
+   dataoff = (*pskb)->nh.iph->ihl*4 + sizeof(struct udphdr);
+   
+   /* Mangle owner and contact info. */
+   bufflen = sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(newip));
+   if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
+       buffer, bufflen, &ct_sip_hdrs[POS_OWNER])) {
+      return 0;   
+   }
+   
+   if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
+       buffer, bufflen, &ct_sip_hdrs[POS_CONECTION])) {
+      return 0;
+   }
+   
+   /* Mangle media port. */
+   bufflen = sprintf(buffer, "%u", port);
+   if (!mangle_sip_packet(pskb, ctinfo, ct, &dptr, (*pskb)->len - dataoff,
+       buffer, bufflen, &ct_sip_hdrs[POS_MEDIA])) {
+      return 0;
+   }
+   
+   return mangle_content_len(pskb, ctinfo, ct, dptr);
+}
+
+/* So, this packet has hit the connection tracking matching code.
+   Mangle it, and change the expectation to match the new version. */
+static unsigned int ip_nat_sdp(struct sk_buff **pskb,
+         enum ip_conntrack_info ctinfo,
+         struct ip_conntrack_expect *exp,
+         char *dptr)
+{
+   struct ip_conntrack *ct = exp->master;
+   uint32_t newip;
+   uint16_t port;
+   
+   DEBUGP("ip_nat_sdp():\n");
+
+   /* Connection will come from reply */
+   newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
+   
+   exp->tuple.dst.ip = newip;
+   exp->saved_proto.udp.port = exp->tuple.dst.u.udp.port;
+   exp->dir = IP_CT_DIR_REPLY;
+
+   /* When you see the packet, we need to NAT it the same as the
+      this one. */
+   exp->expectfn = ip_nat_follow_master;
+
+   /* Try to get same port: if not, try to change it. */
+   for (port = ntohs(exp->saved_proto.udp.port); port != 0; port++) {
+      exp->tuple.dst.u.udp.port = htons(port);
+      if (ip_conntrack_expect_related(exp) == 0)
+         break;
+   }
+   
+   if (port == 0) {
+      ip_conntrack_expect_free(exp);
+      return NF_DROP;
+   }
+   
+   if (!mangle_sdp(pskb, ctinfo, ct, newip, port, dptr)) {
+      ip_conntrack_unexpect_related(exp);
+      return NF_DROP;
+   }
+   return NF_ACCEPT;
+}
+
+static void __exit fini(void)
+{
+   ip_nat_sip_hook = NULL;
+   ip_nat_sdp_hook = NULL;
+   /* Make sure noone calls it, meanwhile. */
+   synchronize_net();
+}
+
+static int __init init(void)
+{
+   BUG_ON(ip_nat_sip_hook);
+   BUG_ON(ip_nat_sdp_hook);
+   ip_nat_sip_hook = ip_nat_sip;
+   ip_nat_sdp_hook = ip_nat_sdp;
+   return 0;
+}
+
+module_init(init);
+module_exit(fini);
Index: sip-conntrack-nat/help
===================================================================
--- sip-conntrack-nat/help   (revision 0)
+++ sip-conntrack-nat/help   (revision 0)
@@ -0,0 +1,7 @@
+This adds CONFIG_IP_NF_SIP: SIP support module for netfilter
+connection tracking and NAT.
+
+The SIP conntrack/NAT modules support the connection tracking/NATing of
+the data streams requested on the dynamic RTP/RTCP ports, as well as mangling
+of SIP requests/responses.
+
Index: sip-conntrack-nat/info
===================================================================
--- sip-conntrack-nat/info   (revision 0)
+++ sip-conntrack-nat/info   (revision 0)
@@ -0,0 +1,5 @@
+Title: SIP connection tracking and NAT helper
+Author: Christian Hentschel <chentschel@arnet.com.ar>
+Status: Alpha
+Repository: extra
+Requires: linux-2.4 >= 2.4.30
如果在src裡加裝patch也就是我給各位的helpers-2.4.20.patch.gz+以上的程式測試過後確定用iptables1.3.0通過測試..也就是說我的patch今天可以算大功告成..

linux的Ha 跟server負載頻衡...不要在nat下的...且裝在各地如台北台南台中...等...要能及時備援..有哪位大大架過crsync2等..可以分享一下安裝設定嗎?要能負載上百萬人的server請問有哪些解決方法異地備援如yahoo那樣有多台機器...ping -c yahoo.com.tw ===XXXXXXXXX.123 xxx.xxx.xxx.124 XXX.XXX.XXX.99等這種做法

請問有沒有高手知到嵌入式disk on modules 防烤備的方法

不知有沒有網友也是做嵌入式linux,用的也是ramdisk..我遇到一個滿頭痛的問題當記憶體備用完機器幾乎不會動了....實體記憶體512mb有沒有人知道哪有相關資料swap請mail to kiki670218@yahoo.com.tw 或回覆我的問題一下

Open Source total-incoming and total-outgoing可以完整互通了各位網友快來完成 屬於我們用的一套免費網路電話巴!經過測試得知h323+sip為了要讓防火牆外的voip可以撥到防火牆內的voip 有粉多種方法 ....最新功能可用linux做多人同步線上會議喔.... 感謝 ....再感謝.........
V-ezlinux有一事想請教網友....有沒有人softswitch有架成功了sip跟h323可以互通 voice codec g.711~g.729都可以通的好心回覆我我們討論一下...

尋找有緣人,預計6月底想辦個聚會,熱愛linux的高手們可以將你們有空的時間給我一下嗎?6 月25 .26可以嗎? mail  to xlinux_huang@hotmail.com