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         exit(-1);
  63 }
  64
  65 static int print_noaopt(struct action_util *au, FILE *f, struct rtattr *opt)
  66 {
  67         if (opt && RTA_PAYLOAD(opt))
  68                 fprintf(f, "[Unknown action, optlen=%u] ",
  69                         (unsigned) RTA_PAYLOAD(opt));
  70         return 0;
  71 }
  72
  73 static int parse_noaopt(struct action_util *au, int *argc_p, char ***argv_p, int code, struct nlmsghdr *n)
  74 {
  75         int argc = *argc_p;
  76         char **argv = *argv_p;
  77
  78         if (argc) {
  79                 fprintf(stderr, "Unknown action \"%s\", hence option \"%s\" is unparsable\n", au->id, *argv);
  80         } else {
  81                 fprintf(stderr, "Unknown action \"%s\"\n", au->id);
  82         }
  83         return -1;
  84 }
  85
  86 struct action_util *get_action_kind(char *str)
  87 {
  88         static void *aBODY;
  89         void *dlh;
  90         char buf[256];
  91         struct action_util *a;
  92 #ifdef CONFIG_GACT
  93         int looked4gact = 0;
  94 restart_s:
  95 #endif
  96         for (a = action_list; a; a = a->next) {
  97                 if (strcmp(a->id, str) == 0)
  98                         return a;
  99         }
 100
 101         snprintf(buf, sizeof(buf), "%s/m_%s.so", get_tc_lib(), str);
 102         dlh = dlopen(buf, RTLD_LAZY | RTLD_GLOBAL);
 103         if (dlh == NULL) {
 104                 dlh = aBODY;
 105                 if (dlh == NULL) {
 106                         dlh = aBODY = dlopen(NULL, RTLD_LAZY);
 107                         if (dlh == NULL)
 108                                 goto noexist;
 109                 }
 110         }
 111
 112         snprintf(buf, sizeof(buf), "%s_action_util", str);
 113         a = dlsym(dlh, buf);
 114         if (a == NULL)
 115                 goto noexist;
 116
 117 reg:
 118         a->next = action_list;
 119         action_list = a;
 120         return a;
 121
 122 noexist:
 123 #ifdef CONFIG_GACT
 124         if (!looked4gact) {
 125                 looked4gact = 1;
 126                 strcpy(str,"gact");
 127                 goto restart_s;
 128         }
 129 #endif
 130         a = malloc(sizeof(*a));
 131         if (a) {
 132                 memset(a, 0, sizeof(*a));
 133                 strncpy(a->id, "noact", 15);
 134                 a->parse_aopt = parse_noaopt;
 135                 a->print_aopt = print_noaopt;
 136                 goto reg;
 137         }
 138         return a;
 139 }
 140
 141 int
 142 new_cmd(char **argv)
 143 {
 144         if ((matches(*argv, "change") == 0) ||
 145                 (matches(*argv, "replace") == 0)||
 146                 (matches(*argv, "delete") == 0)||
 147                 (matches(*argv, "add") == 0))
 148                         return 1;
 149
 150         return 0;
 151
 152 }
 153
 154 int
 155 parse_action(int *argc_p, char ***argv_p, int tca_id, struct nlmsghdr *n)
 156 {
 157         int argc = *argc_p;
 158         char **argv = *argv_p;
 159         struct rtattr *tail, *tail2;
 160         char k[16];
 161         int ok = 0;
 162         int eap = 0; /* expect action parameters */
 163
 164         int ret = 0;
 165         int prio = 0;
 166
 167         if (argc <= 0)
 168                 return -1;
 169
 170         tail = tail2 = NLMSG_TAIL(n);
 171
 172         addattr_l(n, MAX_MSG, tca_id, NULL, 0);
 173
 174         while (argc > 0) {
 175
 176                 memset(k, 0, sizeof (k));
 177
 178                 if (strcmp(*argv, "action") == 0 ) {
 179                         argc--;
 180                         argv++;
 181                         eap = 1;
 182 #ifdef CONFIG_GACT
 183                         if (!gact_ld) {
 184                                 get_action_kind("gact");
 185                         }
 186 #endif
 187                         continue;
 188                 } else if (strcmp(*argv, "help") == 0) {
 189                         return -1;
 190                 } else if (new_cmd(argv)) {
 191                         goto done0;
 192                 } else {
 193                         struct action_util *a = NULL;
 194                         strncpy(k, *argv, sizeof (k) - 1);
 195                         eap = 0;
 196                         if (argc > 0 ) {
 197                                 a = get_action_kind(k);
 198                         } else {
 199 done0:
 200                                 if (ok)
 201                                         break;
 202                                 else
 203                                         goto done;
 204                         }
 205
 206                         if (NULL == a) {
 207                                 goto bad_val;
 208                         }
 209
 210                         tail = NLMSG_TAIL(n);
 211                         addattr_l(n, MAX_MSG, ++prio, NULL, 0);
 212                         addattr_l(n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 213
 214                         ret = a->parse_aopt(a,&argc, &argv, TCA_ACT_OPTIONS, n);
 215
 216                         if (ret < 0) {
 217                                 fprintf(stderr,"bad action parsing\n");
 218                                 goto bad_val;
 219                         }
 220                         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 221                         ok++;
 222                 }
 223
 224         }
 225
 226         if (eap > 0) {
 227                 fprintf(stderr,"bad action empty %d\n",eap);
 228                 goto bad_val;
 229         }
 230
 231         tail2->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail2;
 232
 233 done:
 234         *argc_p = argc;
 235         *argv_p = argv;
 236         return 0;
 237 bad_val:
 238         /* no need to undo things, returning from here should
 239          * cause enough pain */
 240         fprintf(stderr, "parse_action: bad value (%d:%s)!\n",argc,*argv);
 241         return -1;
 242 }
 243
 244 int
 245 tc_print_one_action(FILE * f, struct rtattr *arg)
 246 {
 247
 248         struct rtattr *tb[TCA_ACT_MAX + 1];
 249         int err = 0;
 250         struct action_util *a = NULL;
 251
 252         if (arg == NULL)
 253                 return -1;
 254
 255         parse_rtattr_nested(tb, TCA_ACT_MAX, arg);
 256         if (tb[TCA_ACT_KIND] == NULL) {
 257                 fprintf(stderr, "NULL Action!\n");
 258                 return -1;
 259         }
 260
 261
 262         a = get_action_kind(RTA_DATA(tb[TCA_ACT_KIND]));
 263         if (NULL == a)
 264                 return err;
 265
 266         if (tab_flush) {
 267                 fprintf(f," %s \n", a->id);
 268                 tab_flush = 0;
 269                 return 0;
 270         }
 271
 272         err = a->print_aopt(a,f,tb[TCA_ACT_OPTIONS]);
 273
 274
 275         if (0 > err)
 276                 return err;
 277
 278         if (show_stats && tb[TCA_ACT_STATS]) {
 279                 fprintf(f, "\tAction statistics:\n");
 280                 print_tcstats2_attr(f, tb[TCA_ACT_STATS], "\t", NULL);
 281                 fprintf(f, "\n");
 282         }
 283
 284         return 0;
 285 }
 286
 287 int
 288 tc_print_action(FILE * f, const struct rtattr *arg)
 289 {
 290
 291         int i;
 292         struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
 293
 294         if (arg == NULL)
 295                 return 0;
 296
 297         parse_rtattr_nested(tb, TCA_ACT_MAX_PRIO, arg);
 298
 299         if (tab_flush && NULL != tb[0]  && NULL == tb[1]) {
 300                 int ret = tc_print_one_action(f, tb[0]);
 301                 return ret;
 302         }
 303
 304         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 305                 if (tb[i]) {
 306                         fprintf(f, "\n\taction order %d: ", i + batch_c);
 307                         if (0 > tc_print_one_action(f, tb[i])) {
 308                                 fprintf(f, "Error printing action\n");
 309                         }
 310                 }
 311
 312         }
 313
 314         batch_c+=TCA_ACT_MAX_PRIO ;
 315         return 0;
 316 }
 317
 318 int print_action(const struct sockaddr_nl *who,
 319                            struct nlmsghdr *n,
 320                            void *arg)
 321 {
 322         FILE *fp = (FILE*)arg;
 323         struct tcamsg *t = NLMSG_DATA(n);
 324         int len = n->nlmsg_len;
 325         struct rtattr * tb[TCAA_MAX+1];
 326
 327         len -= NLMSG_LENGTH(sizeof(*t));
 328
 329         if (len < 0) {
 330                 fprintf(stderr, "Wrong len %d\n", len);
 331                 return -1;
 332         }
 333
 334         parse_rtattr(tb, TCAA_MAX, TA_RTA(t), len);
 335
 336         if (NULL == tb[TCA_ACT_TAB]) {
 337                 if (n->nlmsg_type != RTM_GETACTION)
 338                         fprintf(stderr, "print_action: NULL kind\n");
 339                 return -1;
 340         }
 341
 342         if (n->nlmsg_type == RTM_DELACTION) {
 343                 if (n->nlmsg_flags & NLM_F_ROOT) {
 344                         fprintf(fp, "Flushed table ");
 345                         tab_flush = 1;
 346                 } else {
 347                         fprintf(fp, "deleted action ");
 348                 }
 349         }
 350
 351         if (n->nlmsg_type == RTM_NEWACTION)
 352                 fprintf(fp, "Added action ");
 353         tc_print_action(fp, tb[TCA_ACT_TAB]);
 354
 355         return 0;
 356 }
 357
 358 int tc_action_gd(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 359 {
 360         char k[16];
 361         struct action_util *a = NULL;
 362         int argc = *argc_p;
 363         char **argv = *argv_p;
 364         int prio = 0;
 365         int ret = 0;
 366         __u32 i;
 367         struct sockaddr_nl nladdr;
 368         struct rtattr *tail;
 369         struct rtattr *tail2;
 370         struct nlmsghdr *ans = NULL;
 371
 372         struct {
 373                 struct nlmsghdr         n;
 374                 struct tcamsg           t;
 375                 char                    buf[MAX_MSG];
 376         } req;
 377
 378         req.t.tca_family = AF_UNSPEC;
 379
 380         memset(&req, 0, sizeof(req));
 381
 382         memset(&nladdr, 0, sizeof(nladdr));
 383         nladdr.nl_family = AF_NETLINK;
 384
 385         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 386         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 387         req.n.nlmsg_type = cmd;
 388         argc -=1;
 389         argv +=1;
 390
 391
 392         tail = NLMSG_TAIL(&req.n);
 393         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 394
 395         while (argc > 0) {
 396                 if (strcmp(*argv, "action") == 0 ) {
 397                         argc--;
 398                         argv++;
 399                         continue;
 400                 } else if (strcmp(*argv, "help") == 0) {
 401                         return -1;
 402                 }
 403
 404                 strncpy(k, *argv, sizeof (k) - 1);
 405                 a = get_action_kind(k);
 406                 if (NULL == a) {
 407                         fprintf(stderr, "Error: non existent action: %s\n",k);
 408                         ret = -1;
 409                         goto bad_val;
 410                 }
 411                 if (strcmp(a->id, k) != 0) {
 412                         fprintf(stderr, "Error: non existent action: %s\n",k);
 413                         ret = -1;
 414                         goto bad_val;
 415                 }
 416
 417                 argc -=1;
 418                 argv +=1;
 419                 if (argc <= 0) {
 420                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 421                         ret = -1;
 422                         goto bad_val;
 423                 }
 424
 425                 if (matches(*argv, "index") == 0) {
 426                         NEXT_ARG();
 427                         if (get_u32(&i, *argv, 10)) {
 428                                 fprintf(stderr, "Illegal \"index\"\n");
 429                                 ret = -1;
 430                                 goto bad_val;
 431                         }
 432                         argc -=1;
 433                         argv +=1;
 434                 } else {
 435                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 436                         ret = -1;
 437                         goto bad_val;
 438                 }
 439
 440                 tail2 = NLMSG_TAIL(&req.n);
 441                 addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 442                 addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 443                 addattr32(&req.n, MAX_MSG, TCA_ACT_INDEX, i);
 444                 tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 445
 446         }
 447
 448         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 449
 450         req.n.nlmsg_seq = rth.dump = ++rth.seq;
 451         if (cmd == RTM_GETACTION)
 452                 ans = &req.n;
 453
 454         if (rtnl_talk(&rth, &req.n, 0, 0, ans) < 0) {
 455                 fprintf(stderr, "We have an error talking to the kernel\n");
 456                 return 1;
 457         }
 458
 459         if (ans && print_action(NULL, &req.n, (void*)stdout) < 0) {
 460                 fprintf(stderr, "Dump terminated\n");
 461                 return 1;
 462         }
 463
 464         *argc_p = argc;
 465         *argv_p = argv;
 466 bad_val:
 467         return ret;
 468 }
 469
 470 int tc_action_modify(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 471 {
 472         int argc = *argc_p;
 473         char **argv = *argv_p;
 474         int ret = 0;
 475
 476         struct rtattr *tail;
 477         struct {
 478                 struct nlmsghdr         n;
 479                 struct tcamsg           t;
 480                 char                    buf[MAX_MSG];
 481         } req;
 482
 483         req.t.tca_family = AF_UNSPEC;
 484
 485         memset(&req, 0, sizeof(req));
 486
 487         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 488         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 489         req.n.nlmsg_type = cmd;
 490         tail = NLMSG_TAIL(&req.n);
 491         argc -=1;
 492         argv +=1;
 493         if (parse_action(&argc, &argv, TCA_ACT_TAB, &req.n)) {
 494                 fprintf(stderr, "Illegal \"action\"\n");
 495                 return -1;
 496         }
 497         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 498
 499         if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0) {
 500                 fprintf(stderr, "We have an error talking to the kernel\n");
 501                 ret = -1;
 502         }
 503
 504         *argc_p = argc;
 505         *argv_p = argv;
 506
 507         return ret;
 508 }
 509
 510 int tc_act_list_or_flush(int argc, char **argv, int event)
 511 {
 512         int ret = 0, prio = 0, msg_size = 0;
 513         char k[16];
 514         struct rtattr *tail,*tail2;
 515         struct action_util *a = NULL;
 516         struct {
 517                 struct nlmsghdr         n;
 518                 struct tcamsg           t;
 519                 char                    buf[MAX_MSG];
 520         } req;
 521
 522         req.t.tca_family = AF_UNSPEC;
 523
 524         memset(&req, 0, sizeof(req));
 525
 526         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 527
 528         tail = NLMSG_TAIL(&req.n);
 529         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 530         tail2 = NLMSG_TAIL(&req.n);
 531
 532         strncpy(k, *argv, sizeof (k) - 1);
 533 #ifdef CONFIG_GACT
 534         if (!gact_ld) {
 535                 get_action_kind("gact");
 536         }
 537 #endif
 538         a = get_action_kind(k);
 539         if (NULL == a) {
 540                 fprintf(stderr,"bad action %s\n",k);
 541                 goto bad_val;
 542         }
 543         if (strcmp(a->id, k) != 0) {
 544                 fprintf(stderr,"bad action %s\n",k);
 545                 goto bad_val;
 546         }
 547         strncpy(k, *argv, sizeof (k) - 1);
 548
 549         addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 550         addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 551         tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 552         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 553
 554         msg_size = NLMSG_ALIGN(req.n.nlmsg_len) - NLMSG_ALIGN(sizeof(struct nlmsghdr));
 555
 556         if (event == RTM_GETACTION) {
 557                 if (rtnl_dump_request(&rth, event, (void *)&req.t, msg_size) < 0) {
 558                         perror("Cannot send dump request");
 559                         return 1;
 560                 }
 561                 ret = rtnl_dump_filter(&rth, print_action, stdout);
 562         }
 563
 564         if (event == RTM_DELACTION) {
 565                 req.n.nlmsg_len = NLMSG_ALIGN(req.n.nlmsg_len);
 566                 req.n.nlmsg_type = RTM_DELACTION;
 567                 req.n.nlmsg_flags |= NLM_F_ROOT;
 568                 req.n.nlmsg_flags |= NLM_F_REQUEST;
 569                 if (rtnl_talk(&rth, &req.n, 0, 0, NULL) < 0) {
 570                         fprintf(stderr, "We have an error flushing\n");
 571                         return 1;
 572                 }
 573
 574         }
 575
 576 bad_val:
 577
 578         return ret;
 579 }
 580
 581 int do_action(int argc, char **argv)
 582 {
 583
 584         int ret = 0;
 585
 586         while (argc > 0) {
 587
 588                 if (matches(*argv, "add") == 0) {
 589                         ret =  tc_action_modify(RTM_NEWACTION, NLM_F_EXCL|NLM_F_CREATE, &argc, &argv);
 590                 } else if (matches(*argv, "change") == 0 ||
 591                           matches(*argv, "replace") == 0) {
 592                         ret = tc_action_modify(RTM_NEWACTION, NLM_F_CREATE|NLM_F_REPLACE, &argc, &argv);
 593                 } else if (matches(*argv, "delete") == 0) {
 594                         argc -=1;
 595                         argv +=1;
 596                         ret = tc_action_gd(RTM_DELACTION, 0,  &argc, &argv);
 597                 } else if (matches(*argv, "get") == 0) {
 598                         argc -=1;
 599                         argv +=1;
 600                         ret = tc_action_gd(RTM_GETACTION, 0,  &argc, &argv);
 601                 } else if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
 602                                                 || matches(*argv, "lst") == 0) {
 603                         if (argc <= 2) {
 604                                 act_usage();
 605                                 return -1;
 606                         }
 607                         return tc_act_list_or_flush(argc-2, argv+2, RTM_GETACTION);
 608                 } else if (matches(*argv, "flush") == 0) {
 609                         if (argc <= 2) {
 610                                 act_usage();
 611                                 return -1;
 612                         }
 613                         return tc_act_list_or_flush(argc-2, argv+2, RTM_DELACTION);
 614                 } else if (matches(*argv, "help") == 0) {
 615                         act_usage();
 616                         return -1;
 617                 } else {
 618
 619                         ret = -1;
 620                 }
 621
 622                 if (ret < 0) {
 623                         fprintf(stderr, "Command \"%s\" is unknown, try \"tc actions help\".\n", *argv);
 624                         return -1;
 625                 }
 626         }
 627
 628         return 0;
 629 }
 630