tc/f_fw.c

   1 /*
   2  * f_fw.c               FW filter.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <fcntl.h>
  17 #include <sys/socket.h>
  18 #include <netinet/in.h>
  19 #include <arpa/inet.h>
  20 #include <string.h>
  21 #include <linux/if.h> /* IFNAMSIZ */
  22 #include "utils.h"
  23 #include "tc_util.h"
  24
  25 static void explain(void)
  26 {
  27         fprintf(stderr,
  28                 "Usage: ... fw [ classid CLASSID ] [ indev DEV ] [ action ACTION_SPEC ]\n"
  29                 "       CLASSID := Push matching packets to the class identified by CLASSID with format X:Y\n"
  30                 "               CLASSID is parsed as hexadecimal input.\n"
  31                 "       DEV := specify device for incoming device classification.\n"
  32                 "       ACTION_SPEC := Apply an action on matching packets.\n"
  33                 "       NOTE: handle is represented as HANDLE[/FWMASK].\n"
  34                 "               FWMASK is 0xffffffff by default.\n");
  35 }
  36
  37 static int fw_parse_opt(struct filter_util *qu, char *handle, int argc, char **argv, struct nlmsghdr *n)
  38 {
  39         struct tcmsg *t = NLMSG_DATA(n);
  40         struct rtattr *tail;
  41         __u32 mask = 0;
  42         int mask_set = 0;
  43
  44         if (handle) {
  45                 char *slash;
  46
  47                 if ((slash = strchr(handle, '/')) != NULL)
  48                         *slash = '\0';
  49                 if (get_u32(&t->tcm_handle, handle, 0)) {
  50                         fprintf(stderr, "Illegal \"handle\"\n");
  51                         return -1;
  52                 }
  53                 if (slash) {
  54                         if (get_u32(&mask, slash+1, 0)) {
  55                                 fprintf(stderr, "Illegal \"handle\" mask\n");
  56                                 return -1;
  57                         }
  58                         mask_set = 1;
  59                 }
  60         }
  61
  62         if (argc == 0)
  63                 return 0;
  64
  65         tail = addattr_nest(n, 4096, TCA_OPTIONS);
  66
  67         if (mask_set)
  68                 addattr32(n, MAX_MSG, TCA_FW_MASK, mask);
  69
  70         while (argc > 0) {
  71                 if (matches(*argv, "classid") == 0 ||
  72                     matches(*argv, "flowid") == 0) {
  73                         unsigned int handle;
  74
  75                         NEXT_ARG();
  76                         if (get_tc_classid(&handle, *argv)) {
  77                                 fprintf(stderr, "Illegal \"classid\"\n");
  78                                 return -1;
  79                         }
  80                         addattr_l(n, 4096, TCA_FW_CLASSID, &handle, 4);
  81                 } else if (matches(*argv, "police") == 0) {
  82                         NEXT_ARG();
  83                         if (parse_police(&argc, &argv, TCA_FW_POLICE, n)) {
  84                                 fprintf(stderr, "Illegal \"police\"\n");
  85                                 return -1;
  86                         }
  87                         continue;
  88                 } else if (matches(*argv, "action") == 0) {
  89                         NEXT_ARG();
  90                         if (parse_action(&argc, &argv, TCA_FW_ACT, n)) {
  91                                 fprintf(stderr, "Illegal fw \"action\"\n");
  92                                 return -1;
  93                         }
  94                         continue;
  95                 } else if (strcmp(*argv, "indev") == 0) {
  96                         char d[IFNAMSIZ+1] = {};
  97
  98                         argc--;
  99                         argv++;
 100                         if (argc < 1) {
 101                                 fprintf(stderr, "Illegal indev\n");
 102                                 return -1;
 103                         }
 104                         strncpy(d, *argv, sizeof(d) - 1);
 105                         addattr_l(n, MAX_MSG, TCA_FW_INDEV, d, strlen(d) + 1);
 106                 } else if (strcmp(*argv, "help") == 0) {
 107                         explain();
 108                         return -1;
 109                 } else {
 110                         fprintf(stderr, "What is \"%s\"?\n", *argv);
 111                         explain();
 112                         return -1;
 113                 }
 114                 argc--; argv++;
 115         }
 116         addattr_nest_end(n, tail);
 117         return 0;
 118 }
 119
 120 static int fw_print_opt(struct filter_util *qu, FILE *f, struct rtattr *opt, __u32 handle)
 121 {
 122         struct rtattr *tb[TCA_FW_MAX+1];
 123
 124         if (opt == NULL)
 125                 return 0;
 126
 127         parse_rtattr_nested(tb, TCA_FW_MAX, opt);
 128
 129         if (handle || tb[TCA_FW_MASK]) {
 130                 __u32 mark = 0, mask = 0;
 131
 132                 if (handle)
 133                         mark = handle;
 134                 if (tb[TCA_FW_MASK] &&
 135                     (mask = rta_getattr_u32(tb[TCA_FW_MASK])) != 0xFFFFFFFF)
 136                         fprintf(f, "handle 0x%x/0x%x ", mark, mask);
 137                 else
 138                         fprintf(f, "handle 0x%x ", handle);
 139         }
 140
 141         if (tb[TCA_FW_CLASSID]) {
 142                 SPRINT_BUF(b1);
 143                 fprintf(f, "classid %s ", sprint_tc_classid(rta_getattr_u32(tb[TCA_FW_CLASSID]), b1));
 144         }
 145
 146         if (tb[TCA_FW_POLICE])
 147                 tc_print_police(f, tb[TCA_FW_POLICE]);
 148         if (tb[TCA_FW_INDEV]) {
 149                 struct rtattr *idev = tb[TCA_FW_INDEV];
 150
 151                 fprintf(f, "input dev %s ", rta_getattr_str(idev));
 152         }
 153
 154         if (tb[TCA_FW_ACT]) {
 155                 fprintf(f, "\n");
 156                 tc_print_action(f, tb[TCA_FW_ACT], 0);
 157         }
 158         return 0;
 159 }
 160
 161 struct filter_util fw_filter_util = {
 162         .id = "fw",
 163         .parse_fopt = fw_parse_opt,
 164         .print_fopt = fw_print_opt,
 165 };