tc/m_mirred.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * m_egress.c           ingress/egress packet mirror/redir actions module
   4  *
   5  * Authors:  J Hadi Salim (hadi@cyberus.ca)
   6  *
   7  * TODO: Add Ingress support
   8  */
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <fcntl.h>
  14 #include <sys/socket.h>
  15 #include <netinet/in.h>
  16 #include <arpa/inet.h>
  17 #include <string.h>
  18 #include "utils.h"
  19 #include "tc_util.h"
  20 #include "tc_common.h"
  21 #include <linux/tc_act/tc_mirred.h>
  22
  23 static void
  24 explain(void)
  25 {
  26         fprintf(stderr,
  27                 "Usage: mirred <DIRECTION> <ACTION> [index INDEX] <TARGET>\n"
  28                 "where:\n"
  29                 "\tDIRECTION := <ingress | egress>\n"
  30                 "\tACTION := <mirror | redirect>\n"
  31                 "\tINDEX  is the specific policy instance id\n"
  32                 "\tTARGET := <BLOCK | DEVICE>\n"
  33                 "\tDEVICE := dev DEVICENAME\n"
  34                 "\tDEVICENAME is the devicename\n"
  35                 "\tBLOCK := blockid BLOCKID\n"
  36                 "\tBLOCKID := 32-bit unsigned block ID\n");
  37 }
  38
  39 static void
  40 usage(void)
  41 {
  42         explain();
  43         exit(-1);
  44 }
  45
  46 static const char *mirred_n2a(int action)
  47 {
  48         switch (action) {
  49         case TCA_EGRESS_REDIR:
  50                 return "Egress Redirect";
  51         case TCA_INGRESS_REDIR:
  52                 return "Ingress Redirect";
  53         case TCA_EGRESS_MIRROR:
  54                 return "Egress Mirror";
  55         case TCA_INGRESS_MIRROR:
  56                 return "Ingress Mirror";
  57         default:
  58                 return "unknown";
  59         }
  60 }
  61
  62 static const char *mirred_direction(int action)
  63 {
  64         switch (action) {
  65         case TCA_EGRESS_REDIR:
  66         case TCA_EGRESS_MIRROR:
  67                 return "egress";
  68         case TCA_INGRESS_REDIR:
  69         case TCA_INGRESS_MIRROR:
  70                 return "ingress";
  71         default:
  72                 return "unknown";
  73         }
  74 }
  75
  76 static const char *mirred_action(int action)
  77 {
  78         switch (action) {
  79         case TCA_EGRESS_REDIR:
  80         case TCA_INGRESS_REDIR:
  81                 return "redirect";
  82         case TCA_EGRESS_MIRROR:
  83         case TCA_INGRESS_MIRROR:
  84                 return "mirror";
  85         default:
  86                 return "unknown";
  87         }
  88 }
  89
  90 static int
  91 parse_direction(const struct action_util *a, int *argc_p, char ***argv_p,
  92                 int tca_id, struct nlmsghdr *n)
  93 {
  94
  95         int argc = *argc_p;
  96         char **argv = *argv_p;
  97         int ok = 0, iok = 0, mirror = 0, redir = 0, ingress = 0, egress = 0;
  98         struct tc_mirred p = {};
  99         struct rtattr *tail;
 100         char d[IFNAMSIZ] = {};
 101         __u32 blockid = 0;
 102
 103         while (argc > 0) {
 104
 105                 if (matches(*argv, "action") == 0) {
 106                         NEXT_ARG();
 107                         break;
 108                 } else if (!egress && matches(*argv, "egress") == 0) {
 109                         egress = 1;
 110                         if (ingress) {
 111                                 fprintf(stderr,
 112                                         "Can't have both egress and ingress\n");
 113                                 return -1;
 114                         }
 115                         NEXT_ARG();
 116                         ok++;
 117                         continue;
 118                 } else if (!ingress && matches(*argv, "ingress") == 0) {
 119                         ingress = 1;
 120                         if (egress) {
 121                                 fprintf(stderr,
 122                                         "Can't have both ingress and egress\n");
 123                                 return -1;
 124                         }
 125                         NEXT_ARG();
 126                         ok++;
 127                         continue;
 128                 } else {
 129
 130                         if (matches(*argv, "index") == 0) {
 131                                 NEXT_ARG();
 132                                 if (get_u32(&p.index, *argv, 10)) {
 133                                         fprintf(stderr, "Illegal \"index\"\n");
 134                                         return -1;
 135                                 }
 136                                 iok++;
 137                                 if (!ok) {
 138                                         argc--;
 139                                         argv++;
 140                                         break;
 141                                 }
 142                         } else if (!ok) {
 143                                 fprintf(stderr,
 144                                         "was expecting egress or ingress (%s)\n",
 145                                         *argv);
 146                                 break;
 147
 148                         } else if (!mirror && matches(*argv, "mirror") == 0) {
 149                                 mirror = 1;
 150                                 if (redir) {
 151                                         fprintf(stderr,
 152                                                 "Can't have both mirror and redir\n");
 153                                         return -1;
 154                                 }
 155                                 p.eaction = egress ? TCA_EGRESS_MIRROR :
 156                                         TCA_INGRESS_MIRROR;
 157                                 p.action = TC_ACT_PIPE;
 158                                 ok++;
 159                         } else if (!redir && matches(*argv, "redirect") == 0) {
 160                                 redir = 1;
 161                                 if (mirror) {
 162                                         fprintf(stderr,
 163                                                 "Can't have both mirror and redir\n");
 164                                         return -1;
 165                                 }
 166                                 p.eaction = egress ? TCA_EGRESS_REDIR :
 167                                         TCA_INGRESS_REDIR;
 168                                 p.action = TC_ACT_STOLEN;
 169                                 ok++;
 170                         } else if ((redir || mirror)) {
 171                                 if (strcmp(*argv, "blockid") == 0) {
 172                                         if (strlen(d)) {
 173                                                 fprintf(stderr,
 174                                                         "blockid and device are mutually exclusive.\n");
 175                                                 return -1;
 176                                         }
 177                                         NEXT_ARG();
 178                                         if (get_u32(&blockid, *argv, 0) ||
 179                                             !blockid) {
 180                                                 fprintf(stderr,
 181                                                         "invalid block ID");
 182                                                 return -1;
 183                                         }
 184                                         argc--;
 185                                         argv++;
 186                                 }
 187                                 if (argc && matches(*argv, "dev") == 0) {
 188                                         if (blockid) {
 189                                                 fprintf(stderr,
 190                                                         "blockid and device are mutually exclusive.\n");
 191                                                 return -1;
 192                                         }
 193                                         NEXT_ARG();
 194                                         if (strlen(d))
 195                                                 duparg("dev", *argv);
 196
 197                                         strncpy(d, *argv, sizeof(d)-1);
 198                                         argc--;
 199                                         argv++;
 200                                 }
 201
 202                                 break;
 203
 204                         }
 205                 }
 206
 207                 NEXT_ARG();
 208         }
 209
 210         if (!ok && !iok)
 211                 return -1;
 212
 213         if (d[0])  {
 214                 int idx;
 215
 216                 ll_init_map(&rth);
 217
 218                 idx = ll_name_to_index(d);
 219                 if (!idx)
 220                         return nodev(d);
 221
 222                 p.ifindex = idx;
 223         }
 224
 225
 226         if (p.eaction == TCA_EGRESS_MIRROR || p.eaction == TCA_INGRESS_MIRROR)
 227                 parse_action_control_dflt(&argc, &argv, &p.action, false,
 228                                           TC_ACT_PIPE);
 229
 230         if (argc) {
 231                 if (iok && matches(*argv, "index") == 0) {
 232                         fprintf(stderr, "mirred: Illegal double index\n");
 233                         return -1;
 234                 }
 235
 236                 if (matches(*argv, "index") == 0) {
 237                         NEXT_ARG();
 238                         if (get_u32(&p.index, *argv, 10)) {
 239                                 fprintf(stderr,
 240                                         "mirred: Illegal \"index\"\n");
 241                                 return -1;
 242                         }
 243                         argc--;
 244                         argv++;
 245                 }
 246         }
 247
 248         tail = addattr_nest(n, MAX_MSG, tca_id);
 249         addattr_l(n, MAX_MSG, TCA_MIRRED_PARMS, &p, sizeof(p));
 250         if (blockid)
 251                 addattr32(n, MAX_MSG, TCA_MIRRED_BLOCKID, blockid);
 252         addattr_nest_end(n, tail);
 253
 254         *argc_p = argc;
 255         *argv_p = argv;
 256         return 0;
 257 }
 258
 259
 260 static int
 261 parse_mirred(const struct action_util *a, int *argc_p, char ***argv_p,
 262              int tca_id, struct nlmsghdr *n)
 263 {
 264
 265         int argc = *argc_p;
 266         char **argv = *argv_p;
 267
 268         if (argc < 0) {
 269                 fprintf(stderr, "mirred bad argument count %d\n", argc);
 270                 return -1;
 271         }
 272
 273         if (matches(*argv, "mirred") == 0) {
 274                 NEXT_ARG();
 275         } else {
 276                 fprintf(stderr, "mirred bad argument %s\n", *argv);
 277                 return -1;
 278         }
 279
 280
 281         if (matches(*argv, "egress") == 0 || matches(*argv, "ingress") == 0 ||
 282             matches(*argv, "index") == 0) {
 283                 int ret = parse_direction(a, &argc, &argv, tca_id, n);
 284
 285                 if (ret == 0) {
 286                         *argc_p = argc;
 287                         *argv_p = argv;
 288                         return 0;
 289                 }
 290
 291         } else if (matches(*argv, "help") == 0) {
 292                 usage();
 293         } else {
 294                 fprintf(stderr, "mirred option not supported %s\n", *argv);
 295         }
 296
 297         return -1;
 298
 299 }
 300
 301 static int
 302 print_mirred(const struct action_util *au, FILE *f, struct rtattr *arg)
 303 {
 304         struct tc_mirred *p;
 305         struct rtattr *tb[TCA_MIRRED_MAX + 1];
 306         const char *dev;
 307
 308         print_string(PRINT_ANY, "kind", "%s ", "mirred");
 309         if (arg == NULL)
 310                 return 0;
 311
 312         parse_rtattr_nested(tb, TCA_MIRRED_MAX, arg);
 313
 314         if (tb[TCA_MIRRED_PARMS] == NULL) {
 315                 fprintf(stderr, "Missing mirred parameters\n");
 316                 return -1;
 317         }
 318         p = RTA_DATA(tb[TCA_MIRRED_PARMS]);
 319
 320         dev = ll_index_to_name(p->ifindex);
 321         if (dev == 0) {
 322                 fprintf(stderr, "Cannot find device %d\n", p->ifindex);
 323                 return -1;
 324         }
 325
 326         print_string(PRINT_FP, NULL, "(%s", mirred_n2a(p->eaction));
 327         print_string(PRINT_JSON, "mirred_action", NULL,
 328                      mirred_action(p->eaction));
 329         print_string(PRINT_JSON, "direction", NULL,
 330                      mirred_direction(p->eaction));
 331         if (tb[TCA_MIRRED_BLOCKID]) {
 332                 const __u32 *blockid = RTA_DATA(tb[TCA_MIRRED_BLOCKID]);
 333
 334                 print_uint(PRINT_ANY, "to_blockid", " to blockid %u)",
 335                            *blockid);
 336         } else {
 337                 print_string(PRINT_ANY, "to_dev", " to device %s)", dev);
 338         }
 339
 340         print_action_control(f, " ", p->action, "");
 341
 342         print_nl();
 343         print_uint(PRINT_ANY, "index", "\tindex %u", p->index);
 344         print_int(PRINT_ANY, "ref", " ref %d", p->refcnt);
 345         print_int(PRINT_ANY, "bind", " bind %d", p->bindcnt);
 346
 347         if (show_stats) {
 348                 if (tb[TCA_MIRRED_TM]) {
 349                         struct tcf_t *tm = RTA_DATA(tb[TCA_MIRRED_TM]);
 350
 351                         print_tm(f, tm);
 352                 }
 353         }
 354         print_nl();
 355         return 0;
 356 }
 357
 358 struct action_util mirred_action_util = {
 359         .id = "mirred",
 360         .parse_aopt = parse_mirred,
 361         .print_aopt = print_mirred,
 362 };