ebtables-compat: add mark target extension

Translate the mark target extension to the xtables-compat environment.

Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/extensions/libebt_mark.c b/extensions/libebt_mark.c
new file mode 100644 (file)
index 0000000..587b4a6
--- /dev/null
+++ b/extensions/libebt_mark.c
@@ -0,0 +1,191 @@
+/* ebt_mark
+ *
+ * Authors:
+ * Bart De Schuymer <bdschuym@pandora.be>
+ *
+ * July, 2002, September 2006
+ *
+ * Adapted by Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
+ * to use libxtables for ebtables-compat in 2015.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <xtables.h>
+#include <linux/netfilter_bridge/ebt_mark_t.h>
+#include "iptables/nft.h"
+#include "iptables/nft-bridge.h"
+
+static int mark_supplied;
+
+#define MARK_TARGET  '1'
+#define MARK_SETMARK '2'
+#define MARK_ORMARK  '3'
+#define MARK_ANDMARK '4'
+#define MARK_XORMARK '5'
+static struct option brmark_opts[] = {
+       { .name = "mark-target",.has_arg = true,        .val = MARK_TARGET },
+       /* an oldtime messup, we should have always used the scheme
+        * <extension-name>-<option> */
+       { .name = "set-mark",   .has_arg = true,        .val = MARK_SETMARK },
+       { .name = "mark-set",   .has_arg = true,        .val = MARK_SETMARK },
+       { .name = "mark-or",    .has_arg = true,        .val = MARK_ORMARK },
+       { .name = "mark-and",   .has_arg = true,        .val = MARK_ANDMARK },
+       { .name = "mark-xor",   .has_arg = true,        .val = MARK_XORMARK },
+       XT_GETOPT_TABLEEND,
+};
+
+static void brmark_print_help(void)
+{
+       printf(
+       "mark target options:\n"
+       " --mark-set value     : Set nfmark value\n"
+       " --mark-or  value     : Or nfmark with value (nfmark |= value)\n"
+       " --mark-and value     : And nfmark with value (nfmark &= value)\n"
+       " --mark-xor value     : Xor nfmark with value (nfmark ^= value)\n"
+       " --mark-target target : ACCEPT, DROP, RETURN or CONTINUE\n");
+}
+
+static void brmark_init(struct xt_entry_target *target)
+{
+       struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)target->data;
+
+       info->target = EBT_ACCEPT;
+       info->mark = 0;
+       mark_supplied = 0;
+}
+
+#define OPT_MARK_TARGET   0x01
+#define OPT_MARK_SETMARK  0x02
+#define OPT_MARK_ORMARK   0x04
+#define OPT_MARK_ANDMARK  0x08
+#define OPT_MARK_XORMARK  0x10
+
+static int
+brmark_parse(int c, char **argv, int invert, unsigned int *flags,
+            const void *entry, struct xt_entry_target **target)
+{
+       struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)
+                                      (*target)->data;
+       char *end;
+       uint32_t mask;
+
+       switch (c) {
+       case MARK_TARGET:
+               { unsigned int tmp;
+               EBT_CHECK_OPTION(flags, OPT_MARK_TARGET);
+               if (ebt_fill_target(optarg, &tmp))
+                       xtables_error(PARAMETER_PROBLEM,
+                                     "Illegal --mark-target target");
+               /* the 4 lsb are left to designate the target */
+               info->target = (info->target & ~EBT_VERDICT_BITS) |
+                              (tmp & EBT_VERDICT_BITS);
+               }
+               return 1;
+       case MARK_SETMARK:
+               EBT_CHECK_OPTION(flags, OPT_MARK_SETMARK);
+               mask = (OPT_MARK_ORMARK|OPT_MARK_ANDMARK|OPT_MARK_XORMARK);
+               if (*flags & mask)
+                       xtables_error(PARAMETER_PROBLEM,
+                                     "--mark-set cannot be used together with"
+                                     " specific --mark option");
+               info->target = (info->target & EBT_VERDICT_BITS) |
+                              MARK_SET_VALUE;
+               break;
+       case MARK_ORMARK:
+               EBT_CHECK_OPTION(flags, OPT_MARK_ORMARK);
+               mask = (OPT_MARK_SETMARK|OPT_MARK_ANDMARK|OPT_MARK_XORMARK);
+               if (*flags & mask)
+                       xtables_error(PARAMETER_PROBLEM,
+                                     "--mark-or cannot be used together with"
+                                     " specific --mark option");
+               info->target = (info->target & EBT_VERDICT_BITS) |
+                              MARK_OR_VALUE;
+               break;
+       case MARK_ANDMARK:
+               EBT_CHECK_OPTION(flags, OPT_MARK_ANDMARK);
+               mask = (OPT_MARK_SETMARK|OPT_MARK_ORMARK|OPT_MARK_XORMARK);
+               if (*flags & mask)
+                       xtables_error(PARAMETER_PROBLEM,
+                                     "--mark-and cannot be used together with"
+                                     " specific --mark option");
+               info->target = (info->target & EBT_VERDICT_BITS) |
+                              MARK_AND_VALUE;
+               break;
+       case MARK_XORMARK:
+               EBT_CHECK_OPTION(flags, OPT_MARK_XORMARK);
+               mask = (OPT_MARK_SETMARK|OPT_MARK_ANDMARK|OPT_MARK_ORMARK);
+               if (*flags & mask)
+                       xtables_error(PARAMETER_PROBLEM,
+                                     "--mark-xor cannot be used together with"
+                                     " specific --mark option");
+               info->target = (info->target & EBT_VERDICT_BITS) |
+                              MARK_XOR_VALUE;
+               break;
+       default:
+               return 0;
+       }
+       /* mutual code */
+       info->mark = strtoul(optarg, &end, 0);
+       if (*end != '\0' || end == optarg)
+               xtables_error(PARAMETER_PROBLEM, "Bad MARK value '%s'",
+                             optarg);
+
+       mark_supplied = 1;
+       return 1;
+}
+
+static void brmark_print(const void *ip, const struct xt_entry_target *target,
+                        int numeric)
+{
+       struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)target->data;
+       int tmp;
+
+       tmp = info->target & ~EBT_VERDICT_BITS;
+       if (tmp == MARK_SET_VALUE)
+               printf("--mark-set");
+       else if (tmp == MARK_OR_VALUE)
+               printf("--mark-or");
+       else if (tmp == MARK_XOR_VALUE)
+               printf("--mark-xor");
+       else if (tmp == MARK_AND_VALUE)
+               printf("--mark-and");
+       else
+               xtables_error(PARAMETER_PROBLEM, "Unknown mark action");
+
+       printf(" 0x%lx", info->mark);
+       tmp = info->target | ~EBT_VERDICT_BITS;
+       printf(" --mark-target %s", ebt_target_name(tmp));
+}
+
+static void brmark_final_check(unsigned int flags)
+{
+       if (mark_supplied == 0)
+               xtables_error(PARAMETER_PROBLEM, "No mark value supplied");
+
+       if (!flags)
+               xtables_error(PARAMETER_PROBLEM,
+                             "You must specify some option");
+}
+
+static struct xtables_target brmark_target = {
+       .name           = "mark",
+       .revision       = 0,
+       .version        = XTABLES_VERSION,
+       .family         = NFPROTO_BRIDGE,
+       .size           = XT_ALIGN(sizeof(struct ebt_mark_t_info)),
+       .userspacesize  = XT_ALIGN(sizeof(struct ebt_mark_t_info)),
+       .help           = brmark_print_help,
+       .init           = brmark_init,
+       .parse          = brmark_parse,
+       .final_check    = brmark_final_check,
+       .print          = brmark_print,
+       .extra_opts     = brmark_opts,
+};
+
+void _init(void)
+{
+       xtables_register_target(&brmark_target);
+}

diff --git a/include/linux/netfilter_bridge/ebt_mark_t.h b/include/linux/netfilter_bridge/ebt_mark_t.h
new file mode 100644 (file)
index 0000000..7d5a268
--- /dev/null
+++ b/include/linux/netfilter_bridge/ebt_mark_t.h
@@ -0,0 +1,23 @@
+#ifndef __LINUX_BRIDGE_EBT_MARK_T_H
+#define __LINUX_BRIDGE_EBT_MARK_T_H
+
+/* The target member is reused for adding new actions, the
+ * value of the real target is -1 to -NUM_STANDARD_TARGETS.
+ * For backward compatibility, the 4 lsb (2 would be enough,
+ * but let's play it safe) are kept to designate this target.
+ * The remaining bits designate the action. By making the set
+ * action 0xfffffff0, the result will look ok for older
+ * versions. [September 2006] */
+#define MARK_SET_VALUE (0xfffffff0)
+#define MARK_OR_VALUE  (0xffffffe0)
+#define MARK_AND_VALUE (0xffffffd0)
+#define MARK_XOR_VALUE (0xffffffc0)
+
+struct ebt_mark_t_info {
+       unsigned long mark;
+       /* EBT_ACCEPT, EBT_DROP, EBT_CONTINUE or EBT_RETURN */
+       int target;
+};
+#define EBT_MARK_TARGET "mark"
+
+#endif