blob: ba79308ba8354cd716d4d097b204d354b46b8fec [file] [log] [blame]
/*
* m_skbmod.c skb modifier action module
*
* This program is free software; you can distribute 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.
*
* Authors: J Hadi Salim (jhs@mojatatu.com)
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <syslog.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <linux/netdevice.h>
#include "rt_names.h"
#include "utils.h"
#include "tc_util.h"
#include <linux/tc_act/tc_skbmod.h>
static void skbmod_explain(void)
{
fprintf(stderr,
"Usage:... skbmod {[set <SETTABLE>] [swap <SWAPABLE>]} [CONTROL] [index INDEX]\n"
"where SETTABLE is: [dmac DMAC] [smac SMAC] [etype ETYPE]\n"
"where SWAPABLE is: \"mac\" to swap mac addresses\n"
"note: \"swap mac\" is done after any outstanding D/SMAC change\n"
"\tDMAC := 6 byte Destination MAC address\n"
"\tSMAC := optional 6 byte Source MAC address\n"
"\tETYPE := optional 16 bit ethertype\n"
"\tCONTROL := reclassify | pipe | drop | continue | ok |\n"
"\t goto chain <CHAIN_INDEX>\n"
"\tINDEX := skbmod index value to use\n");
}
static void skbmod_usage(void)
{
skbmod_explain();
exit(-1);
}
static int parse_skbmod(struct action_util *a, int *argc_p, char ***argv_p,
int tca_id, struct nlmsghdr *n)
{
int argc = *argc_p;
char **argv = *argv_p;
int ok = 0;
struct tc_skbmod p;
struct rtattr *tail;
char dbuf[ETH_ALEN];
char sbuf[ETH_ALEN];
__u16 skbmod_etype = 0;
char *daddr = NULL;
char *saddr = NULL;
memset(&p, 0, sizeof(p));
if (argc <= 0)
return -1;
while (argc > 0) {
if (matches(*argv, "skbmod") == 0) {
NEXT_ARG();
continue;
} else if (matches(*argv, "swap") == 0) {
NEXT_ARG();
continue;
} else if (matches(*argv, "mac") == 0) {
p.flags |= SKBMOD_F_SWAPMAC;
ok += 1;
} else if (matches(*argv, "set") == 0) {
NEXT_ARG();
continue;
} else if (matches(*argv, "etype") == 0) {
NEXT_ARG();
if (get_u16(&skbmod_etype, *argv, 0))
invarg("ethertype is invalid", *argv);
fprintf(stderr, "skbmod etype 0x%x\n", skbmod_etype);
p.flags |= SKBMOD_F_ETYPE;
ok += 1;
} else if (matches(*argv, "dmac") == 0) {
NEXT_ARG();
daddr = *argv;
if (sscanf(daddr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
dbuf, dbuf + 1, dbuf + 2,
dbuf + 3, dbuf + 4, dbuf + 5) != 6) {
fprintf(stderr, "Invalid dst mac address %s\n",
daddr);
return -1;
}
p.flags |= SKBMOD_F_DMAC;
fprintf(stderr, "dst MAC address <%s>\n", daddr);
ok += 1;
} else if (matches(*argv, "smac") == 0) {
NEXT_ARG();
saddr = *argv;
if (sscanf(saddr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
sbuf, sbuf + 1, sbuf + 2,
sbuf + 3, sbuf + 4, sbuf + 5) != 6) {
fprintf(stderr, "Invalid smac address %s\n",
saddr);
return -1;
}
p.flags |= SKBMOD_F_SMAC;
fprintf(stderr, "src MAC address <%s>\n", saddr);
ok += 1;
} else if (matches(*argv, "help") == 0) {
skbmod_usage();
} else {
break;
}
argc--;
argv++;
}
parse_action_control_dflt(&argc, &argv, &p.action, false, TC_ACT_PIPE);
if (argc) {
if (matches(*argv, "index") == 0) {
NEXT_ARG();
if (get_u32(&p.index, *argv, 0)) {
fprintf(stderr, "skbmod: Illegal \"index\"\n");
return -1;
}
ok++;
argc--;
argv++;
}
}
if (!ok) {
fprintf(stderr, "skbmod requires at least one option\n");
skbmod_usage();
}
tail = NLMSG_TAIL(n);
addattr_l(n, MAX_MSG, tca_id, NULL, 0);
addattr_l(n, MAX_MSG, TCA_SKBMOD_PARMS, &p, sizeof(p));
if (daddr)
addattr_l(n, MAX_MSG, TCA_SKBMOD_DMAC, dbuf, ETH_ALEN);
if (skbmod_etype)
addattr16(n, MAX_MSG, TCA_SKBMOD_ETYPE, skbmod_etype);
if (saddr)
addattr_l(n, MAX_MSG, TCA_SKBMOD_SMAC, sbuf, ETH_ALEN);
tail->rta_len = (void *)NLMSG_TAIL(n) - (void *)tail;
*argc_p = argc;
*argv_p = argv;
return 0;
}
static int print_skbmod(struct action_util *au, FILE *f, struct rtattr *arg)
{
struct tc_skbmod *p = NULL;
struct rtattr *tb[TCA_SKBMOD_MAX + 1];
__u16 skbmod_etype = 0;
int has_optional = 0;
SPRINT_BUF(b1);
SPRINT_BUF(b2);
if (arg == NULL)
return -1;
parse_rtattr_nested(tb, TCA_SKBMOD_MAX, arg);
if (tb[TCA_SKBMOD_PARMS] == NULL) {
fprintf(f, "[NULL skbmod parameters]");
return -1;
}
p = RTA_DATA(tb[TCA_SKBMOD_PARMS]);
fprintf(f, "skbmod ");
print_action_control(f, "", p->action, " ");
if (tb[TCA_SKBMOD_ETYPE]) {
skbmod_etype = rta_getattr_u16(tb[TCA_SKBMOD_ETYPE]);
has_optional = 1;
fprintf(f, "set etype 0x%X ", skbmod_etype);
}
if (has_optional)
fprintf(f, "\n\t ");
if (tb[TCA_SKBMOD_DMAC]) {
has_optional = 1;
fprintf(f, "set dmac %s ",
ll_addr_n2a(RTA_DATA(tb[TCA_SKBMOD_DMAC]),
RTA_PAYLOAD(tb[TCA_SKBMOD_DMAC]), 0, b1,
sizeof(b1)));
}
if (tb[TCA_SKBMOD_SMAC]) {
has_optional = 1;
fprintf(f, "set smac %s ",
ll_addr_n2a(RTA_DATA(tb[TCA_SKBMOD_SMAC]),
RTA_PAYLOAD(tb[TCA_SKBMOD_SMAC]), 0, b2,
sizeof(b2)));
}
if (p->flags & SKBMOD_F_SWAPMAC)
fprintf(f, "swap mac ");
fprintf(f, "\n\t index %u ref %d bind %d", p->index, p->refcnt,
p->bindcnt);
if (show_stats) {
if (tb[TCA_SKBMOD_TM]) {
struct tcf_t *tm = RTA_DATA(tb[TCA_SKBMOD_TM]);
print_tm(f, tm);
}
}
fprintf(f, "\n");
return 0;
}
struct action_util skbmod_action_util = {
.id = "skbmod",
.parse_aopt = parse_skbmod,
.print_aopt = print_skbmod,
};