summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorEmmanuel Roger <winfield@freegates.be>2000-10-04 15:19:31 +0000
committerRusty Russell <rusty@rustcorp.com.au>2000-10-04 15:19:31 +0000
commit3071913784b69423fd25c3db2344e585872920cc (patch)
tree77b4d5d229dd22090fe619474b5ab76dcfa69d23
parent3c7a6c479f3eccd65a78dc103f33f4085e8e4703 (diff)
Emmanuel Roger's string matching patch.
-rwxr-xr-xextensions/.string-test2
-rw-r--r--extensions/libipt_string.c127
2 files changed, 129 insertions, 0 deletions
diff --git a/extensions/.string-test b/extensions/.string-test
new file mode 100755
index 00000000..609f1c2b
--- /dev/null
+++ b/extensions/.string-test
@@ -0,0 +1,2 @@
+#! /bin/sh
+[ -f $KERNEL_DIR/include/linux/netfilter_ipv4/ipt_string.h ] && echo string
diff --git a/extensions/libipt_string.c b/extensions/libipt_string.c
new file mode 100644
index 00000000..25dacdc5
--- /dev/null
+++ b/extensions/libipt_string.c
@@ -0,0 +1,127 @@
+/* Shared library add-on to iptables to add string matching support.
+ *
+ * Copyright (C) 2000 Emmanuel Roger <winfield@freegates.be>
+ */
+#include <stdio.h>
+#include <netdb.h>
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+
+#include <iptables.h>
+#include <linux/netfilter_ipv4/ipt_string.h>
+
+/* Function which prints out usage message. */
+static void
+help(void)
+{
+ printf(
+"STRING match v%s options:\n"
+"--string [!] string Match a string in a packet\n",
+NETFILTER_VERSION);
+
+ fputc('\n', stdout);
+}
+
+static struct option opts[] = {
+ { "string", 1, 0, '1' },
+ {0}
+};
+
+/* Initialize the match. */
+static void
+init(struct ipt_entry_match *m, unsigned int *nfcache)
+{
+ *nfcache |= NFC_UNKNOWN;
+}
+
+static void
+parse_string(const unsigned char *s, struct ipt_string_info *info)
+{
+ if (strlen(s) <= 255) strcpy(info->string, s);
+ else exit_error(PARAMETER_PROBLEM, "STRING too long `%s'", s);
+}
+
+/* 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_string_info *stringinfo = (struct ipt_string_info *)(*match)->data;
+
+ switch (c) {
+ case '1':
+ if (check_inverse(optarg, &invert))
+ optind++;
+ parse_string(argv[optind-1], stringinfo);
+ if (invert)
+ stringinfo->invert = 1;
+ *flags = 1;
+ break;
+
+ default:
+ return 0;
+ }
+ return 1;
+}
+
+static void
+print_string(char string[], int invert, int numeric)
+{
+
+ if (invert)
+ fputc('!', stdout);
+ printf("%s ",string);
+}
+
+/* Final check; must have specified --string. */
+static void
+final_check(unsigned int flags)
+{
+ if (!flags)
+ exit_error(PARAMETER_PROBLEM,
+ "STRING match: You must specify `--string'");
+}
+
+/* Prints out the matchinfo. */
+static void
+print(const struct ipt_ip *ip,
+ const struct ipt_entry_match *match,
+ int numeric)
+{
+ printf("STRING match ");
+ print_string(((struct ipt_string_info *)match->data)->string,
+ ((struct ipt_string_info *)match->data)->invert, numeric);
+}
+
+/* Saves the union ipt_matchinfo in parsable form to stdout. */
+static void
+save(const struct ipt_ip *ip, const struct ipt_entry_match *match)
+{
+ printf("--tos ");
+ print_string(((struct ipt_string_info *)match->data)->string,
+ ((struct ipt_string_info *)match->data)->invert, 0);
+}
+
+struct iptables_match string
+= { NULL,
+ "string",
+ NETFILTER_VERSION,
+ IPT_ALIGN(sizeof(struct ipt_string_info)),
+ IPT_ALIGN(sizeof(struct ipt_string_info)),
+ &help,
+ &init,
+ &parse,
+ &final_check,
+ &print,
+ &save,
+ opts
+};
+
+void _init(void)
+{
+ register_match(&string);
+}