tc/m_action.c

   1 /*
   2  * m_action.c           Action Management
   3  *
   4  *              This program is free software; you can distribute 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:  J Hadi Salim (hadi@cyberus.ca)
  10  *
  11  * TODO:
  12  * - parse to be passed a filedescriptor for logging purposes
  13  *
  14 */
  15
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <unistd.h>
  19 #include <syslog.h>
  20 #include <fcntl.h>
  21 #include <sys/socket.h>
  22 #include <netinet/in.h>
  23 #include <arpa/inet.h>
  24 #include <string.h>
  25 #include <dlfcn.h>
  26
  27 #include "utils.h"
  28 #include "tc_common.h"
  29 #include "tc_util.h"
  30
  31 static struct action_util * action_list;
  32 #ifdef CONFIG_GACT
  33 int gact_ld = 0 ; //fuckin backward compatibility
  34 #endif
  35 int batch_c = 0;
  36 int tab_flush = 0;
  37
  38 void act_usage(void)
  39 {
  40         /*XXX: In the near future add a action->print_help to improve
  41          * usability
  42          * This would mean new tc will not be backward compatible
  43          * with any action .so from the old days. But if someone really
  44          * does that, they would know how to fix this ..
  45          *
  46          */
  47         fprintf (stderr, "usage: tc actions <ACTSPECOP>*\n");
  48         fprintf(stderr,
  49                 "Where: \tACTSPECOP := ACR | GD | FL\n"
  50                 "\tACR := add | change | replace <ACTSPEC>* \n"
  51                 "\tGD := get | delete | <ACTISPEC>*\n"
  52                 "\tFL := ls | list | flush | <ACTNAMESPEC>\n"
  53                 "\tACTNAMESPEC :=  action <ACTNAME>\n"
  54                 "\tACTISPEC := <ACTNAMESPEC> <INDEXSPEC>\n"
  55                 "\tACTSPEC := action <ACTDETAIL> [INDEXSPEC]\n"
  56                 "\tINDEXSPEC := index <32 bit indexvalue>\n"
  57                 "\tACTDETAIL := <ACTNAME> <ACTPARAMS>\n"
  58                 "\t\tExample ACTNAME is gact, mirred etc\n"
  59                 "\t\tEach action has its own parameters (ACTPARAMS)\n"
  60                 "\n");
  61 }
  62
  63 static int print_noaopt(struct action_util *au, FILE *f, struct rtattr *opt)
  64 {
  65         if (opt && RTA_PAYLOAD(opt))
  66                 fprintf(f, "[Unknown action, optlen=%u] ",
  67                         (unsigned) RTA_PAYLOAD(opt));
  68         return 0;
  69 }
  70
  71 static int parse_noaopt(struct action_util *au, int *argc_p, char ***argv_p, int code, struct nlmsghdr *n)
  72 {
  73         int argc = *argc_p;
  74         char **argv = *argv_p;
  75
  76         if (argc) {
  77                 fprintf(stderr, "Unknown action \"%s\", hence option \"%s\" is unparsable\n", au->id, *argv);
  78         } else {
  79                 fprintf(stderr, "Unknown action \"%s\"\n", au->id);
  80         }
  81         return -1;
  82 }
  83
  84 struct action_util *get_action_kind(char *str)
  85 {
  86         static void *aBODY;
  87         void *dlh;
  88         char buf[256];
  89         struct action_util *a;
  90 #ifdef CONFIG_GACT
  91         int looked4gact = 0;
  92 restart_s:
  93 #endif
  94         for (a = action_list; a; a = a->next) {
  95                 if (strcmp(a->id, str) == 0)
  96                         return a;
  97         }
  98
  99         snprintf(buf, sizeof(buf), "m_%s.so", str);
 100         dlh = dlopen(buf, RTLD_LAZY);
 101         if (dlh == NULL) {
 102                 dlh = aBODY;
 103                 if (dlh == NULL) {
 104                         dlh = aBODY = dlopen(NULL, RTLD_LAZY);
 105                         if (dlh == NULL)
 106                                 goto noexist;
 107                 }
 108         }
 109
 110         snprintf(buf, sizeof(buf), "%s_action_util", str);
 111         a = dlsym(dlh, buf);
 112         if (a == NULL)
 113                 goto noexist;
 114
 115 reg:
 116         a->next = action_list;
 117         action_list = a;
 118         return a;
 119
 120 noexist:
 121 #ifdef CONFIG_GACT
 122         if (!looked4gact) {
 123                 looked4gact = 1;
 124                 strcpy(str,"gact");
 125                 goto restart_s;
 126         }
 127 #endif
 128         a = malloc(sizeof(*a));
 129         if (a) {
 130                 memset(a, 0, sizeof(*a));
 131                 strncpy(a->id, "noact", 15);
 132                 a->parse_aopt = parse_noaopt;
 133                 a->print_aopt = print_noaopt;
 134                 goto reg;
 135         }
 136         return a;
 137 }
 138
 139 int
 140 new_cmd(char **argv)
 141 {
 142         if ((matches(*argv, "change") == 0) ||
 143                 (matches(*argv, "replace") == 0)||
 144                 (matches(*argv, "delete") == 0)||
 145                 (matches(*argv, "add") == 0))
 146                         return 1;
 147
 148         return 0;
 149
 150 }
 151
 152 int
 153 parse_action(int *argc_p, char ***argv_p, int tca_id, struct nlmsghdr *n)
 154 {
 155         int argc = *argc_p;
 156         char **argv = *argv_p;
 157         struct rtattr *tail, *tail2;
 158         char k[16];
 159         int ok = 0;
 160         int eap = 0; /* expect action parameters */
 161
 162         int ret = 0;
 163         int prio = 0;
 164
 165         if (argc <= 0)
 166                 return -1;
 167
 168         tail = tail2 = NLMSG_TAIL(n);
 169
 170         addattr_l(n, MAX_MSG, tca_id, NULL, 0);
 171
 172         while (argc > 0) {
 173
 174                 memset(k, 0, sizeof (k));
 175
 176                 if (strcmp(*argv, "action") == 0 ) {
 177                         argc--;
 178                         argv++;
 179                         eap = 1;
 180 #ifdef CONFIG_GACT
 181                         if (!gact_ld) {
 182                                 get_action_kind("gact");
 183                         }
 184 #endif
 185                         continue;
 186                 } else if (strcmp(*argv, "help") == 0) {
 187                         return -1;
 188                 } else if (new_cmd(argv)) {
 189                         goto done0;
 190                 } else {
 191                         struct action_util *a = NULL;
 192                         strncpy(k, *argv, sizeof (k) - 1);
 193                         eap = 0;
 194                         if (argc > 0 ) {
 195                                 a = get_action_kind(k);
 196                         } else {
 197 done0:
 198                                 if (ok)
 199                                         break;
 200                                 else
 201                                         goto done;
 202                         }
 203
 204                         if (NULL == a) {
 205                                 goto bad_val;
 206                         }
 207
 208                         tail = NLMSG_TAIL(n);
 209                         addattr_l(n, MAX_MSG, ++prio, NULL, 0);
 210                         addattr_l(n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 211
 212                         ret = a->parse_aopt(a,&argc, &argv, TCA_ACT_OPTIONS, n);
 213
 214                         if (ret < 0) {
 215                                 fprintf(stderr,"bad action parsing\n");
 216                                 goto bad_val;
 217                         }
 218                         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 219                         ok++;
 220                 }
 221
 222         }
 223
 224         if (eap > 0) {
 225                 fprintf(stderr,"bad action empty %d\n",eap);
 226                 goto bad_val;
 227         }
 228
 229         tail2->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail2;
 230
 231 done:
 232         *argc_p = argc;
 233         *argv_p = argv;
 234         return 0;
 235 bad_val:
 236         /* no need to undo things, returning from here should
 237          * cause enough pain */
 238         fprintf(stderr, "parse_action: bad value (%d:%s)!\n",argc,*argv);
 239         return -1;
 240 }
 241
 242 int
 243 tc_print_one_action(FILE * f, struct rtattr *arg)
 244 {
 245
 246         struct rtattr *tb[TCA_ACT_MAX + 1];
 247         int err = 0;
 248         struct action_util *a = NULL;
 249
 250         if (arg == NULL)
 251                 return -1;
 252
 253         parse_rtattr_nested(tb, TCA_ACT_MAX, arg);
 254         if (tb[TCA_ACT_KIND] == NULL) {
 255                 fprintf(stderr, "NULL Action!\n");
 256                 return -1;
 257         }
 258
 259
 260         a = get_action_kind(RTA_DATA(tb[TCA_ACT_KIND]));
 261         if (NULL == a)
 262                 return err;
 263
 264         if (tab_flush) {
 265                 fprintf(f," %s \n", a->id);
 266                 tab_flush = 0;
 267                 return 0;
 268         }
 269
 270         err = a->print_aopt(a,f,tb[TCA_ACT_OPTIONS]);
 271
 272
 273         if (0 > err)
 274                 return err;
 275
 276         if (show_stats && tb[TCA_ACT_STATS]) {
 277                 fprintf(f, "\tAction statistics:\n");
 278                 print_tcstats2_attr(f, tb[TCA_ACT_STATS], "\t", NULL);
 279                 fprintf(f, "\n");
 280         }
 281
 282         return 0;
 283 }
 284
 285 int
 286 tc_print_action(FILE * f, const struct rtattr *arg)
 287 {
 288
 289         int i;
 290         struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
 291
 292         if (arg == NULL)
 293                 return 0;
 294
 295         parse_rtattr_nested(tb, TCA_ACT_MAX_PRIO, arg);
 296
 297         if (tab_flush && NULL != tb[0]  && NULL == tb[1]) {
 298                 int ret = tc_print_one_action(f, tb[0]);
 299                 return ret;
 300         }
 301
 302         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 303                 if (tb[i]) {
 304                         fprintf(f, "\n\taction order %d: ", i + batch_c);
 305                         if (0 > tc_print_one_action(f, tb[i])) {
 306                                 fprintf(f, "Error printing action\n");
 307                         }
 308                 }
 309
 310         }
 311
 312         batch_c+=TCA_ACT_MAX_PRIO ;
 313         return 0;
 314 }
 315
 316 int print_action(const struct sockaddr_nl *who,
 317                            struct nlmsghdr *n,
 318                            void *arg)
 319 {
 320         FILE *fp = (FILE*)arg;
 321         struct tcamsg *t = NLMSG_DATA(n);
 322         int len = n->nlmsg_len;
 323         struct rtattr * tb[TCAA_MAX+1];
 324
 325         len -= NLMSG_LENGTH(sizeof(*t));
 326
 327         if (len < 0) {
 328                 fprintf(stderr, "Wrong len %d\n", len);
 329                 return -1;
 330         }
 331
 332         parse_rtattr(tb, TCAA_MAX, TA_RTA(t), len);
 333
 334         if (NULL == tb[TCA_ACT_TAB]) {
 335                 if (n->nlmsg_type != RTM_GETACTION)
 336                         fprintf(stderr, "print_action: NULL kind\n");
 337                 return -1;
 338         }
 339
 340         if (n->nlmsg_type == RTM_DELACTION) {
 341                 if (n->nlmsg_flags & NLM_F_ROOT) {
 342                         fprintf(fp, "Flushed table ");
 343                         tab_flush = 1;
 344                 } else {
 345                         fprintf(fp, "deleted action ");
 346                 }
 347         }
 348
 349         if (n->nlmsg_type == RTM_NEWACTION)
 350                 fprintf(fp, "Added action ");
 351         tc_print_action(fp, tb[TCA_ACT_TAB]);
 352
 353         return 0;
 354 }
 355
 356 int tc_action_gd(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 357 {
 358         char k[16];
 359         struct action_util *a = NULL;
 360         int argc = *argc_p;
 361         char **argv = *argv_p;
 362         int prio = 0;
 363         int ret = 0;
 364         __u32 i;
 365         struct sockaddr_nl nladdr;
 366         struct rtattr *tail;
 367         struct rtattr *tail2;
 368         struct nlmsghdr *ans = NULL;
 369
 370         struct {
 371                 struct nlmsghdr         n;
 372                 struct tcamsg           t;
 373                 char                    buf[MAX_MSG];
 374         } req;
 375
 376         req.t.tca_family = AF_UNSPEC;
 377
 378         memset(&req, 0, sizeof(req));
 379
 380         memset(&nladdr, 0, sizeof(nladdr));
 381         nladdr.nl_family = AF_NETLINK;
 382
 383         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 384         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 385         req.n.nlmsg_type = cmd;
 386         argc -=1;
 387         argv +=1;
 388
 389
 390         tail = NLMSG_TAIL(&req.n);
 391         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 392
 393         while (argc > 0) {
 394                 if (strcmp(*argv, "action") == 0 ) {
 395                         argc--;
 396                         argv++;
 397                         continue;
 398                 } else if (strcmp(*argv, "help") == 0) {
 399                         return -1;
 400                 }
 401
 402                 strncpy(k, *argv, sizeof (k) - 1);
 403                 a = get_action_kind(k);
 404                 if (NULL == a) {
 405                         fprintf(stderr, "Error: non existent action: %s\n",k);
 406                         ret = -1;
 407                         goto bad_val;
 408                 }
 409                 if (strcmp(a->id, k) != 0) {
 410                         fprintf(stderr, "Error: non existent action: %s\n",k);
 411                         ret = -1;
 412                         goto bad_val;
 413                 }
 414
 415                 argc -=1;
 416                 argv +=1;
 417                 if (argc <= 0) {
 418                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 419                         ret = -1;
 420                         goto bad_val;
 421                 }
 422
 423                 if (matches(*argv, "index") == 0) {
 424                         NEXT_ARG();
 425                         if (get_u32(&i, *argv, 10)) {
 426                                 fprintf(stderr, "Illegal \"index\"\n");
 427                                 ret = -1;
 428                                 goto bad_val;
 429                         }
 430                         argc -=1;
 431                         argv +=1;
 432                 } else {
 433                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 434                         ret = -1;
 435                         goto bad_val;
 436                 }
 437
 438                 tail2 = NLMSG_TAIL(&req.n);
 439                 addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 440                 addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 441                 addattr32(&req.n, MAX_MSG, TCA_ACT_INDEX, i);
 442                 tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 443
 444         }
 445
 446         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 447
 448         req.n.nlmsg_seq = rth.dump = ++rth.seq;
 449         if (cmd == RTM_GETACTION)
 450                 ans = &req.n;
 451
 452         if (rtnl_talk(&rth, &req.n, 0, 0, ans, NULL, NULL) < 0) {
 453                 fprintf(stderr, "We have an error talking to the kernel\n");
 454                 return 1;
 455         }
 456
 457         if (ans && print_action(NULL, &req.n, (void*)stdout) < 0) {
 458                 fprintf(stderr, "Dump terminated\n");
 459                 return 1;
 460         }
 461
 462         *argc_p = argc;
 463         *argv_p = argv;
 464 bad_val:
 465         return ret;
 466 }
 467
 468 int tc_action_modify(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 469 {
 470         int argc = *argc_p;
 471         char **argv = *argv_p;
 472         int ret = 0;
 473
 474         struct rtattr *tail;
 475         struct {
 476                 struct nlmsghdr         n;
 477                 struct tcamsg           t;
 478                 char                    buf[MAX_MSG];
 479         } req;
 480
 481         req.t.tca_family = AF_UNSPEC;
 482
 483         memset(&req, 0, sizeof(req));
 484
 485         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 486         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 487         req.n.nlmsg_type = cmd;
 488         tail = NLMSG_TAIL(&req.n);
 489         argc -=1;
 490         argv +=1;
 491         if (parse_action(&argc, &argv, TCA_ACT_TAB, &req.n)) {
 492                 fprintf(stderr, "Illegal \"action\"\n");
 493                 return -1;
 494         }
 495         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 496
 497         if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) {
 498                 fprintf(stderr, "We have an error talking to the kernel\n");
 499                 ret = -1;
 500         }
 501
 502         *argc_p = argc;
 503         *argv_p = argv;
 504
 505         return ret;
 506 }
 507
 508 int tc_act_list_or_flush(int argc, char **argv, int event)
 509 {
 510         int ret = 0, prio = 0, msg_size = 0;
 511         char k[16];
 512         struct rtattr *tail,*tail2;
 513         struct action_util *a = NULL;
 514         struct {
 515                 struct nlmsghdr         n;
 516                 struct tcamsg           t;
 517                 char                    buf[MAX_MSG];
 518         } req;
 519
 520         req.t.tca_family = AF_UNSPEC;
 521
 522         memset(&req, 0, sizeof(req));
 523
 524         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 525
 526         tail = NLMSG_TAIL(&req.n);
 527         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 528         tail2 = NLMSG_TAIL(&req.n);
 529
 530         strncpy(k, *argv, sizeof (k) - 1);
 531 #ifdef CONFIG_GACT
 532         if (!gact_ld) {
 533                 get_action_kind("gact");
 534         }
 535 #endif
 536         a = get_action_kind(k);
 537         if (NULL == a) {
 538                 fprintf(stderr,"bad action %s\n",k);
 539                 goto bad_val;
 540         }
 541         if (strcmp(a->id, k) != 0) {
 542                 fprintf(stderr,"bad action %s\n",k);
 543                 goto bad_val;
 544         }
 545         strncpy(k, *argv, sizeof (k) - 1);
 546
 547         addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 548         addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 549         tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 550         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 551
 552         msg_size = NLMSG_ALIGN(req.n.nlmsg_len) - NLMSG_ALIGN(sizeof(struct nlmsghdr));
 553
 554         if (event == RTM_GETACTION) {
 555                 if (rtnl_dump_request(&rth, event, (void *)&req.t, msg_size) < 0) {
 556                         perror("Cannot send dump request");
 557                         return 1;
 558                 }
 559                 ret = rtnl_dump_filter(&rth, print_action, stdout, NULL, NULL);
 560         }
 561
 562         if (event == RTM_DELACTION) {
 563                 req.n.nlmsg_len = NLMSG_ALIGN(req.n.nlmsg_len);
 564                 req.n.nlmsg_type = RTM_DELACTION;
 565                 req.n.nlmsg_flags |= NLM_F_ROOT;
 566                 req.n.nlmsg_flags |= NLM_F_REQUEST;
 567                 if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) {
 568                         fprintf(stderr, "We have an error flushing\n");
 569                         return 1;
 570                 }
 571
 572         }
 573
 574 bad_val:
 575
 576         return ret;
 577 }
 578
 579 int do_action(int argc, char **argv)
 580 {
 581
 582         int ret = 0;
 583
 584         while (argc > 0) {
 585
 586                 if (matches(*argv, "add") == 0) {
 587                         ret =  tc_action_modify(RTM_NEWACTION, NLM_F_EXCL|NLM_F_CREATE, &argc, &argv);
 588                 } else if (matches(*argv, "change") == 0 ||
 589                           matches(*argv, "replace") == 0) {
 590                         ret = tc_action_modify(RTM_NEWACTION, NLM_F_CREATE|NLM_F_REPLACE, &argc, &argv);
 591                 } else if (matches(*argv, "delete") == 0) {
 592                         argc -=1;
 593                         argv +=1;
 594                         ret = tc_action_gd(RTM_DELACTION, 0,  &argc, &argv);
 595                 } else if (matches(*argv, "get") == 0) {
 596                         argc -=1;
 597                         argv +=1;
 598                         ret = tc_action_gd(RTM_GETACTION, 0,  &argc, &argv);
 599                 } else if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
 600                                                 || matches(*argv, "lst") == 0) {
 601                         if (argc <= 2) {
 602                                 act_usage();
 603                                 return -1;
 604                         }
 605                         return tc_act_list_or_flush(argc-2, argv+2, RTM_GETACTION);
 606                 } else if (matches(*argv, "flush") == 0) {
 607                         if (argc <= 2) {
 608                                 act_usage();
 609                                 return -1;
 610                         }
 611                         return tc_act_list_or_flush(argc-2, argv+2, RTM_DELACTION);
 612                 } else if (matches(*argv, "help") == 0) {
 613                         act_usage();
 614                         return -1;
 615                 } else {
 616
 617                         ret = -1;
 618                 }
 619
 620                 if (ret < 0) {
 621                         fprintf(stderr, "Command \"%s\" is unknown, try \"tc actions help\".\n", *argv);
 622                         return -1;
 623                 }
 624         }
 625
 626         return 0;
 627 }
 628