openwrt/package/iptables/patches/002-layer7-1.5nbd.patch

Index: iptables-1.3.7/extensions/.layer7-test
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ iptables-1.3.7/extensions/.layer7-test	2007-06-04 13:21:43.708331992 +0200
@@ -0,0 +1,2 @@
+#! /bin/sh
+[ -f $KERNEL_DIR/include/linux/netfilter_ipv4/ipt_layer7.h ] && echo layer7
Index: iptables-1.3.7/extensions/ipt_layer7.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ iptables-1.3.7/extensions/ipt_layer7.h	2007-06-04 13:21:43.708331992 +0200
@@ -0,0 +1,27 @@
+/* 
+  By Matthew Strait <quadong@users.sf.net>, Dec 2003.
+  http://l7-filter.sf.net
+
+  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.
+  http://www.gnu.org/licenses/gpl.txt
+*/
+
+#ifndef _IPT_LAYER7_H
+#define _IPT_LAYER7_H
+
+#define MAX_PATTERN_LEN 8192
+#define MAX_PROTOCOL_LEN 256
+
+typedef char *(*proc_ipt_search) (char *, char, char *);
+
+struct ipt_layer7_info {
+    char protocol[MAX_PROTOCOL_LEN];
+    char invert:1;
+    char pattern[MAX_PATTERN_LEN];
+	char pkt;
+};
+
+#endif /* _IPT_LAYER7_H */
Index: iptables-1.3.7/extensions/libipt_layer7.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ iptables-1.3.7/extensions/libipt_layer7.c	2007-06-04 13:21:43.709331840 +0200
@@ -0,0 +1,358 @@
+/* 
+   Shared library add-on to iptables to add layer 7 matching support. 
+  
+   By Matthew Strait <quadong@users.sf.net>, Oct 2003.
+
+   http://l7-filter.sf.net 
+
+   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.
+   http://www.gnu.org/licenses/gpl.txt
+
+   Based on libipt_string.c (C) 2000 Emmanuel Roger <winfield@freegates.be>
+*/
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <ctype.h>
+#include <dirent.h>
+
+#include <iptables.h>
+#include "ipt_layer7.h"
+
+#define MAX_FN_LEN 256
+
+static char l7dir[MAX_FN_LEN] = "\0";
+
+/* Function which prints out usage message. */
+static void help(void)
+{
+	printf(
+	"LAYER7 match v%s options:\n"
+	"--l7dir <directory>  : Look for patterns here instead of /etc/l7-protocols/\n"
+	"                       (--l7dir must be specified before --l7proto if used!)\n"
+	"--l7proto [!] <name> : Match the protocol defined in /etc/l7-protocols/name.pat\n"
+	"--l7pkt              : Skip connection tracking and match individual packets\n",
+	IPTABLES_VERSION);
+	fputc('\n', stdout);
+}
+
+static struct option opts[] = {
+	{ .name = "l7proto", .has_arg = 1, .flag = 0, .val = '1' },
+	{ .name = "l7dir",   .has_arg = 1, .flag = 0, .val = '2' },
+	{ .name = "l7pkt",   .has_arg = 0, .flag = 0, .val = '3' },
+	{ .name = 0 }
+};
+
+/* reads filename, puts protocol info into layer7_protocol_info, number of protocols to numprotos */
+int parse_protocol_file(char * filename, const unsigned char * protoname, struct ipt_layer7_info *info)
+{
+	FILE * f;
+	char * line = NULL;
+	size_t len = 0;
+
+	enum { protocol, pattern, done } datatype = protocol;
+
+	f = fopen(filename, "r");
+
+	if(!f)
+		return 0;
+
+	while(getline(&line, &len, f) != -1)
+	{
+		if(strlen(line) < 2 || line[0] == '#')
+			continue;
+
+		/* strip the pesky newline... */
+		if(line[strlen(line) - 1] == '\n')
+			line[strlen(line) - 1] = '\0';
+
+		if(datatype == protocol)
+		{
+			if(strcmp(line, protoname))
+				exit_error(OTHER_PROBLEM, 
+					"Protocol name (%s) doesn't match file name (%s).  Bailing out\n",
+					protoname, filename);
+
+			if(strlen(line) >= MAX_PROTOCOL_LEN)
+				 exit_error(PARAMETER_PROBLEM, 
+					"Protocol name in %s too long!", filename);
+			strncpy(info->protocol, line, MAX_PROTOCOL_LEN);
+
+			datatype = pattern; 
+		}
+		else if(datatype == pattern)
+		{
+			if(strlen(line) >= MAX_PATTERN_LEN)
+				 exit_error(PARAMETER_PROBLEM, "Pattern in %s too long!", filename);
+			strncpy(info->pattern, line, MAX_PATTERN_LEN);
+			
+			datatype = done;			
+			break;
+		}
+		else
+			exit_error(OTHER_PROBLEM, "Internal error");
+	}
+
+	if(datatype != done)
+		exit_error(OTHER_PROBLEM, "Failed to get all needed data from %s", filename);
+
+	if(line) free(line);
+	fclose(f);
+
+	return 1;
+
+/*
+	fprintf(stderr, "protocol: %s\npattern: %s\n\n", 
+			info->protocol,
+			info->pattern);
+*/
+}
+
+static int hex2dec(char c)
+{
+        switch (c)
+        {
+                case '0' ... '9':
+                        return c - '0';
+                case 'a' ... 'f':
+                        return c - 'a' + 10;
+                case 'A' ... 'F':
+                        return c - 'A' + 10;
+                default:
+                        exit_error(OTHER_PROBLEM, "hex2dec: bad value!\n");
+                        return 0;
+        }
+}
+
+/* takes a string with \xHH escapes and returns one with the characters 
+they stand for */
+static char * pre_process(char * s)
+{
+	char * result = malloc(strlen(s) + 1);
+	int sindex = 0, rindex = 0;
+        while( sindex < strlen(s) )
+        {
+            if( sindex + 3 < strlen(s) &&
+                s[sindex] == '\\' && s[sindex+1] == 'x' && 
+                isxdigit(s[sindex + 2]) && isxdigit(s[sindex + 3]) ) 
+                {
+                        /* carefully remember to call tolower here... */
+                        result[rindex] = tolower( hex2dec(s[sindex + 2])*16 +
+                                                  hex2dec(s[sindex + 3] ) );
+                        sindex += 3; /* 4 total */
+                }
+                else
+                        result[rindex] = tolower(s[sindex]);
+
+		sindex++; 
+		rindex++;
+        }
+	result[rindex] = '\0';
+
+	return result;
+}
+
+#define MAX_SUBDIRS 128
+char ** readl7dir(char * dirname)
+{
+        DIR             * scratchdir;
+        struct dirent   ** namelist;
+	char ** subdirs = malloc(MAX_SUBDIRS * sizeof(char *));
+
+        int n, d = 1;
+	subdirs[0] = "";
+
+        n = scandir(dirname, &namelist, 0, alphasort);
+
+	if (n < 0)
+	{
+            perror("scandir");
+	    exit_error(OTHER_PROBLEM, "Couldn't open %s\n", dirname);
+	}
+        else 
+	{
+            	while(n--) 
+		{
+			char fulldirname[MAX_FN_LEN];
+
+			snprintf(fulldirname, MAX_FN_LEN, "%s/%s", dirname, namelist[n]->d_name);
+
+                	if((scratchdir = opendir(fulldirname)) != NULL)
+			{
+				closedir(scratchdir);
+
+				if(!strcmp(namelist[n]->d_name, ".") || 
+				   !strcmp(namelist[n]->d_name, ".."))
+					/* do nothing */ ;
+				else
+				{
+					subdirs[d] = malloc(strlen(namelist[n]->d_name) + 1);
+					strcpy(subdirs[d], namelist[n]->d_name);
+					d++;
+					if(d >= MAX_SUBDIRS - 1)
+					{
+						fprintf(stderr, 
+						  "Too many subdirectories, skipping the rest!\n");
+						break;
+					}
+				}
+			}
+                	free(namelist[n]);
+            	}
+            	free(namelist);
+        }
+	
+	subdirs[d] = NULL;
+
+	return subdirs;
+}
+
+static void
+parse_layer7_protocol(const unsigned char *s, struct ipt_layer7_info *info)
+{
+	char filename[MAX_FN_LEN];
+	char * dir = NULL;
+	char ** subdirs;
+	int n = 0, done = 0;
+
+	if(strlen(l7dir) > 0)
+		dir = l7dir;
+	else
+		dir = "/etc/l7-protocols";
+
+	subdirs = readl7dir(dir);
+
+	while(subdirs[n] != NULL)
+	{
+		int c = snprintf(filename, MAX_FN_LEN, "%s/%s/%s.pat", dir, subdirs[n], s);
+
+		//fprintf(stderr, "Trying to find pattern in %s ... ", filename);
+
+		if(c > MAX_FN_LEN)
+		{
+			exit_error(OTHER_PROBLEM, 
+				"Filename beginning with %s is too long!\n", filename);
+		}
+
+		/* read in the pattern from the file */
+		if(parse_protocol_file(filename, s, info))
+		{
+			//fprintf(stderr, "found\n");
+			done = 1;
+			break;
+		}
+		
+		//fprintf(stderr, "not found\n");
+
+		n++;
+	}
+
+	if(!done)
+		exit_error(OTHER_PROBLEM, 
+			"Couldn't find a pattern definition file for %s.\n", s);
+
+	/* process \xHH escapes and tolower everything. (our regex lib has no
+	case insensitivity option.) */
+	strncpy(info->pattern, pre_process(info->pattern), MAX_PATTERN_LEN);
+}
+
+/* Function which parses command options; returns true if it ate an option */
+static int parse(int c, char **argv, int invert, unsigned int *flags,
+      const struct ipt_entry *entry, unsigned int *nfcache,
+      struct ipt_entry_match **match)
+{
+	struct ipt_layer7_info *layer7info = 
+		(struct ipt_layer7_info *)(*match)->data;
+
+	switch (c) {
+	case '1':
+		check_inverse(optarg, &invert, &optind, 0);
+		parse_layer7_protocol(argv[optind-1], layer7info);
+		if (invert)
+			layer7info->invert = 1;
+		*flags = 1;
+		break;
+
+	case '2':
+		/* not going to use this, but maybe we need to strip a ! anyway (?) */
+		check_inverse(optarg, &invert, &optind, 0);
+
+		if(strlen(argv[optind-1]) >= MAX_FN_LEN)
+			exit_error(PARAMETER_PROBLEM, "directory name too long\n");
+
+		strncpy(l7dir, argv[optind-1], MAX_FN_LEN);
+
+		*flags = 1;
+		break;
+	case '3':
+		layer7info->pkt = 1;
+		break;
+
+	default:
+		return 0;
+	}
+
+	return 1;
+}
+
+/* Final check; must have specified --pattern. */
+static void final_check(unsigned int flags)
+{
+	if (!flags)
+		exit_error(PARAMETER_PROBLEM,
+			   "LAYER7 match: You must specify `--pattern'");
+}
+
+static void print_protocol(char s[], int invert, int numeric)
+{
+	fputs("l7proto ", stdout);
+	if (invert) fputc('!', stdout);
+	printf("%s ", s);
+}
+
+/* Prints out the matchinfo. */
+static void print(const struct ipt_ip *ip,
+      const struct ipt_entry_match *match,
+      int numeric)
+{
+	printf("LAYER7 ");
+
+	print_protocol(((struct ipt_layer7_info *)match->data)->protocol,
+		  ((struct ipt_layer7_info *)match->data)->invert, numeric);
+
+	if (((struct ipt_layer7_info *)match->data)->pkt)
+		printf("l7pkt ");
+}
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
+{
+        const struct ipt_layer7_info *info =
+            (const struct ipt_layer7_info*) match->data;
+
+        printf("--l7proto %s%s ", (info->invert)   ? "! ": "", info->protocol);
+}
+
+static struct iptables_match layer7 = { 
+    .name          = "layer7",
+    .version       = IPTABLES_VERSION,
+    .size          = IPT_ALIGN(sizeof(struct ipt_layer7_info)),
+    .userspacesize = IPT_ALIGN(sizeof(struct ipt_layer7_info)),
+    .help          = &help,
+    .parse         = &parse,
+    .final_check   = &final_check,
+    .print         = &print,
+    .save          = &save,
+    .extra_opts    = opts
+};
+
+void _init(void)
+{
+	register_match(&layer7);
+}
Index: iptables-1.3.7/extensions/libipt_layer7.man
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ iptables-1.3.7/extensions/libipt_layer7.man	2007-06-04 13:21:43.709331840 +0200
@@ -0,0 +1,13 @@
+This module matches packets based on the application layer data of 
+their connections.  It uses regular expression matching to compare 
+the application layer data to regular expressions found it the layer7 
+configuration files.  This is an experimental module which can be found at 
+http://l7-filter.sf.net.  It takes two options.
+.TP
+.BI "--l7proto " "\fIprotocol\fP"
+Match the specified protocol.  The protocol name must match a file 
+name in /etc/l7-protocols/
+.TP
+.BI "--l7dir " "\fIdirectory\fP"
+Use \fIdirectory\fP instead of /etc/l7-protocols/
+