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 tab_flush = 0;
  36
  37 static void act_usage(void)
  38 {
  39         /*XXX: In the near future add a action->print_help to improve
  40          * usability
  41          * This would mean new tc will not be backward compatible
  42          * with any action .so from the old days. But if someone really
  43          * does that, they would know how to fix this ..
  44          *
  45         */
  46         fprintf (stderr, "usage: tc actions <ACTSPECOP>*\n");
  47         fprintf(stderr,
  48                 "Where: \tACTSPECOP := ACR | GD | FL\n"
  49                         "\tACR := add | change | replace <ACTSPEC>* \n"
  50                         "\tGD := get | delete | <ACTISPEC>*\n"
  51                         "\tFL := ls | list | flush | <ACTNAMESPEC>\n"
  52                         "\tACTNAMESPEC :=  action <ACTNAME>\n"
  53                         "\tACTISPEC := <ACTNAMESPEC> <INDEXSPEC>\n"
  54                         "\tACTSPEC := action <ACTDETAIL> [INDEXSPEC]\n"
  55                         "\tINDEXSPEC := index <32 bit indexvalue>\n"
  56                         "\tACTDETAIL := <ACTNAME> <ACTPARAMS>\n"
  57                         "\t\tExample ACTNAME is gact, mirred, bpf, etc\n"
  58                         "\t\tEach action has its own parameters (ACTPARAMS)\n"
  59                         "\n");
  60
  61         exit(-1);
  62 }
  63
  64 static int print_noaopt(struct action_util *au, FILE *f, struct rtattr *opt)
  65 {
  66         if (opt && RTA_PAYLOAD(opt))
  67                 fprintf(f, "[Unknown action, optlen=%u] ",
  68                         (unsigned) RTA_PAYLOAD(opt));
  69         return 0;
  70 }
  71
  72 static int parse_noaopt(struct action_util *au, int *argc_p, char ***argv_p, int code, struct nlmsghdr *n)
  73 {
  74         int argc = *argc_p;
  75         char **argv = *argv_p;
  76
  77         if (argc) {
  78                 fprintf(stderr, "Unknown action \"%s\", hence option \"%s\" is unparsable\n", au->id, *argv);
  79         } else {
  80                 fprintf(stderr, "Unknown action \"%s\"\n", au->id);
  81         }
  82         return -1;
  83 }
  84
  85 static struct action_util *get_action_kind(char *str)
  86 {
  87         static void *aBODY;
  88         void *dlh;
  89         char buf[256];
  90         struct action_util *a;
  91 #ifdef CONFIG_GACT
  92         int looked4gact = 0;
  93 restart_s:
  94 #endif
  95         for (a = action_list; a; a = a->next) {
  96                 if (strcmp(a->id, str) == 0)
  97                         return a;
  98         }
  99
 100         snprintf(buf, sizeof(buf), "%s/m_%s.so", get_tc_lib(), str);
 101         dlh = dlopen(buf, RTLD_LAZY | RTLD_GLOBAL);
 102         if (dlh == NULL) {
 103                 dlh = aBODY;
 104                 if (dlh == NULL) {
 105                         dlh = aBODY = dlopen(NULL, RTLD_LAZY);
 106                         if (dlh == NULL)
 107                                 goto noexist;
 108                 }
 109         }
 110
 111         snprintf(buf, sizeof(buf), "%s_action_util", str);
 112         a = dlsym(dlh, buf);
 113         if (a == NULL)
 114                 goto noexist;
 115
 116 reg:
 117         a->next = action_list;
 118         action_list = a;
 119         return a;
 120
 121 noexist:
 122 #ifdef CONFIG_GACT
 123         if (!looked4gact) {
 124                 looked4gact = 1;
 125                 strcpy(str,"gact");
 126                 goto restart_s;
 127         }
 128 #endif
 129         a = malloc(sizeof(*a));
 130         if (a) {
 131                 memset(a, 0, sizeof(*a));
 132                 strncpy(a->id, "noact", 15);
 133                 a->parse_aopt = parse_noaopt;
 134                 a->print_aopt = print_noaopt;
 135                 goto reg;
 136         }
 137         return a;
 138 }
 139
 140 static int
 141 new_cmd(char **argv)
 142 {
 143         if ((matches(*argv, "change") == 0) ||
 144                 (matches(*argv, "replace") == 0)||
 145                 (matches(*argv, "delete") == 0)||
 146                 (matches(*argv, "get") == 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, "flowid") == 0) {
 189                         break;
 190                 } else if (strcmp(*argv, "classid") == 0) {
 191                         break;
 192                 } else if (strcmp(*argv, "help") == 0) {
 193                         return -1;
 194                 } else if (new_cmd(argv)) {
 195                         goto done0;
 196                 } else {
 197                         struct action_util *a = NULL;
 198                         strncpy(k, *argv, sizeof (k) - 1);
 199                         eap = 0;
 200                         if (argc > 0 ) {
 201                                 a = get_action_kind(k);
 202                         } else {
 203 done0:
 204                                 if (ok)
 205                                         break;
 206                                 else
 207                                         goto done;
 208                         }
 209
 210                         if (NULL == a) {
 211                                 goto bad_val;
 212                         }
 213
 214                         tail = NLMSG_TAIL(n);
 215                         addattr_l(n, MAX_MSG, ++prio, NULL, 0);
 216                         addattr_l(n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 217
 218                         ret = a->parse_aopt(a,&argc, &argv, TCA_ACT_OPTIONS, n);
 219
 220                         if (ret < 0) {
 221                                 fprintf(stderr,"bad action parsing\n");
 222                                 goto bad_val;
 223                         }
 224                         tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
 225                         ok++;
 226                 }
 227
 228         }
 229
 230         if (eap > 0) {
 231                 fprintf(stderr,"bad action empty %d\n",eap);
 232                 goto bad_val;
 233         }
 234
 235         tail2->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail2;
 236
 237 done:
 238         *argc_p = argc;
 239         *argv_p = argv;
 240         return 0;
 241 bad_val:
 242         /* no need to undo things, returning from here should
 243          * cause enough pain */
 244         fprintf(stderr, "parse_action: bad value (%d:%s)!\n",argc,*argv);
 245         return -1;
 246 }
 247
 248 static int
 249 tc_print_one_action(FILE * f, struct rtattr *arg)
 250 {
 251
 252         struct rtattr *tb[TCA_ACT_MAX + 1];
 253         int err = 0;
 254         struct action_util *a = NULL;
 255
 256         if (arg == NULL)
 257                 return -1;
 258
 259         parse_rtattr_nested(tb, TCA_ACT_MAX, arg);
 260
 261         if (tb[TCA_ACT_KIND] == NULL) {
 262                 fprintf(stderr, "NULL Action!\n");
 263                 return -1;
 264         }
 265
 266
 267         a = get_action_kind(RTA_DATA(tb[TCA_ACT_KIND]));
 268         if (NULL == a)
 269                 return err;
 270
 271         err = a->print_aopt(a, f, tb[TCA_ACT_OPTIONS]);
 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 static int
 286 tc_print_action_flush(FILE *f, const struct rtattr *arg)
 287 {
 288
 289         struct rtattr *tb[TCA_MAX + 1];
 290         int err = 0;
 291         struct action_util *a = NULL;
 292         __u32 *delete_count = 0;
 293
 294         parse_rtattr_nested(tb, TCA_MAX, arg);
 295
 296         if (tb[TCA_KIND] == NULL) {
 297                 fprintf(stderr, "NULL Action!\n");
 298                 return -1;
 299         }
 300
 301         a = get_action_kind(RTA_DATA(tb[TCA_KIND]));
 302         if (NULL == a)
 303                 return err;
 304
 305         delete_count = RTA_DATA(tb[TCA_FCNT]);
 306         fprintf(f," %s (%d entries)\n", a->id, *delete_count);
 307         tab_flush = 0;
 308         return 0;
 309 }
 310
 311 int
 312 tc_print_action(FILE *f, const struct rtattr *arg)
 313 {
 314
 315         int i;
 316         struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
 317
 318         if (arg == NULL)
 319                 return 0;
 320
 321         parse_rtattr_nested(tb, TCA_ACT_MAX_PRIO, arg);
 322
 323         if (tab_flush && NULL != tb[0]  && NULL == tb[1])
 324                 return tc_print_action_flush(f, tb[0]);
 325
 326         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 327                 if (tb[i]) {
 328                         fprintf(f, "\n\taction order %d: ", i);
 329                         if (0 > tc_print_one_action(f, tb[i])) {
 330                                 fprintf(f, "Error printing action\n");
 331                         }
 332                 }
 333
 334         }
 335
 336         return 0;
 337 }
 338
 339 int print_action(const struct sockaddr_nl *who,
 340                            struct nlmsghdr *n,
 341                            void *arg)
 342 {
 343         FILE *fp = (FILE*)arg;
 344         struct tcamsg *t = NLMSG_DATA(n);
 345         int len = n->nlmsg_len;
 346         struct rtattr * tb[TCAA_MAX+1];
 347
 348         len -= NLMSG_LENGTH(sizeof(*t));
 349
 350         if (len < 0) {
 351                 fprintf(stderr, "Wrong len %d\n", len);
 352                 return -1;
 353         }
 354
 355         parse_rtattr(tb, TCAA_MAX, TA_RTA(t), len);
 356
 357         if (NULL == tb[TCA_ACT_TAB]) {
 358                 if (n->nlmsg_type != RTM_GETACTION)
 359                         fprintf(stderr, "print_action: NULL kind\n");
 360                 return -1;
 361         }
 362
 363         if (n->nlmsg_type == RTM_DELACTION) {
 364                 if (n->nlmsg_flags & NLM_F_ROOT) {
 365                         fprintf(fp, "Flushed table ");
 366                         tab_flush = 1;
 367                 } else {
 368                         fprintf(fp, "deleted action ");
 369                 }
 370         }
 371
 372         if (n->nlmsg_type == RTM_NEWACTION)
 373                 fprintf(fp, "Added action ");
 374         tc_print_action(fp, tb[TCA_ACT_TAB]);
 375
 376         return 0;
 377 }
 378
 379 static int tc_action_gd(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 380 {
 381         char k[16];
 382         struct action_util *a = NULL;
 383         int argc = *argc_p;
 384         char **argv = *argv_p;
 385         int prio = 0;
 386         int ret = 0;
 387         __u32 i;
 388         struct sockaddr_nl nladdr;
 389         struct rtattr *tail;
 390         struct rtattr *tail2;
 391         struct nlmsghdr *ans = NULL;
 392
 393         struct {
 394                 struct nlmsghdr         n;
 395                 struct tcamsg           t;
 396                 char                    buf[MAX_MSG];
 397         } req;
 398
 399         req.t.tca_family = AF_UNSPEC;
 400
 401         memset(&req, 0, sizeof(req));
 402
 403         memset(&nladdr, 0, sizeof(nladdr));
 404         nladdr.nl_family = AF_NETLINK;
 405
 406         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 407         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 408         req.n.nlmsg_type = cmd;
 409         argc -=1;
 410         argv +=1;
 411
 412
 413         tail = NLMSG_TAIL(&req.n);
 414         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 415
 416         while (argc > 0) {
 417                 if (strcmp(*argv, "action") == 0 ) {
 418                         argc--;
 419                         argv++;
 420                         continue;
 421                 } else if (strcmp(*argv, "help") == 0) {
 422                         return -1;
 423                 }
 424
 425                 strncpy(k, *argv, sizeof (k) - 1);
 426                 a = get_action_kind(k);
 427                 if (NULL == a) {
 428                         fprintf(stderr, "Error: non existent action: %s\n",k);
 429                         ret = -1;
 430                         goto bad_val;
 431                 }
 432                 if (strcmp(a->id, k) != 0) {
 433                         fprintf(stderr, "Error: non existent action: %s\n",k);
 434                         ret = -1;
 435                         goto bad_val;
 436                 }
 437
 438                 argc -=1;
 439                 argv +=1;
 440                 if (argc <= 0) {
 441                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 442                         ret = -1;
 443                         goto bad_val;
 444                 }
 445
 446                 if (matches(*argv, "index") == 0) {
 447                         NEXT_ARG();
 448                         if (get_u32(&i, *argv, 10)) {
 449                                 fprintf(stderr, "Illegal \"index\"\n");
 450                                 ret = -1;
 451                                 goto bad_val;
 452                         }
 453                         argc -=1;
 454                         argv +=1;
 455                 } else {
 456                         fprintf(stderr, "Error: no index specified action: %s\n",k);
 457                         ret = -1;
 458                         goto bad_val;
 459                 }
 460
 461                 tail2 = NLMSG_TAIL(&req.n);
 462                 addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 463                 addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 464                 addattr32(&req.n, MAX_MSG, TCA_ACT_INDEX, i);
 465                 tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 466
 467         }
 468
 469         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 470
 471         req.n.nlmsg_seq = rth.dump = ++rth.seq;
 472         if (cmd == RTM_GETACTION)
 473                 ans = &req.n;
 474
 475         if (rtnl_talk(&rth, &req.n, ans, MAX_MSG) < 0) {
 476                 fprintf(stderr, "We have an error talking to the kernel\n");
 477                 return 1;
 478         }
 479
 480         if (ans && print_action(NULL, &req.n, (void*)stdout) < 0) {
 481                 fprintf(stderr, "Dump terminated\n");
 482                 return 1;
 483         }
 484
 485         *argc_p = argc;
 486         *argv_p = argv;
 487 bad_val:
 488         return ret;
 489 }
 490
 491 static int tc_action_modify(int cmd, unsigned flags, int *argc_p, char ***argv_p)
 492 {
 493         int argc = *argc_p;
 494         char **argv = *argv_p;
 495         int ret = 0;
 496
 497         struct rtattr *tail;
 498         struct {
 499                 struct nlmsghdr         n;
 500                 struct tcamsg           t;
 501                 char                    buf[MAX_MSG];
 502         } req;
 503
 504         req.t.tca_family = AF_UNSPEC;
 505
 506         memset(&req, 0, sizeof(req));
 507
 508         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 509         req.n.nlmsg_flags = NLM_F_REQUEST|flags;
 510         req.n.nlmsg_type = cmd;
 511         tail = NLMSG_TAIL(&req.n);
 512         argc -=1;
 513         argv +=1;
 514         if (parse_action(&argc, &argv, TCA_ACT_TAB, &req.n)) {
 515                 fprintf(stderr, "Illegal \"action\"\n");
 516                 return -1;
 517         }
 518         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 519
 520         if (rtnl_talk(&rth, &req.n, NULL, 0) < 0) {
 521                 fprintf(stderr, "We have an error talking to the kernel\n");
 522                 ret = -1;
 523         }
 524
 525         *argc_p = argc;
 526         *argv_p = argv;
 527
 528         return ret;
 529 }
 530
 531 static int tc_act_list_or_flush(int argc, char **argv, int event)
 532 {
 533         int ret = 0, prio = 0, msg_size = 0;
 534         char k[16];
 535         struct rtattr *tail,*tail2;
 536         struct action_util *a = NULL;
 537         struct {
 538                 struct nlmsghdr         n;
 539                 struct tcamsg           t;
 540                 char                    buf[MAX_MSG];
 541         } req;
 542
 543         req.t.tca_family = AF_UNSPEC;
 544
 545         memset(&req, 0, sizeof(req));
 546
 547         req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 548
 549         tail = NLMSG_TAIL(&req.n);
 550         addattr_l(&req.n, MAX_MSG, TCA_ACT_TAB, NULL, 0);
 551         tail2 = NLMSG_TAIL(&req.n);
 552
 553         strncpy(k, *argv, sizeof (k) - 1);
 554 #ifdef CONFIG_GACT
 555         if (!gact_ld) {
 556                 get_action_kind("gact");
 557         }
 558 #endif
 559         a = get_action_kind(k);
 560         if (NULL == a) {
 561                 fprintf(stderr,"bad action %s\n",k);
 562                 goto bad_val;
 563         }
 564         if (strcmp(a->id, k) != 0) {
 565                 fprintf(stderr,"bad action %s\n",k);
 566                 goto bad_val;
 567         }
 568         strncpy(k, *argv, sizeof (k) - 1);
 569
 570         addattr_l(&req.n, MAX_MSG, ++prio, NULL, 0);
 571         addattr_l(&req.n, MAX_MSG, TCA_ACT_KIND, k, strlen(k) + 1);
 572         tail2->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail2;
 573         tail->rta_len = (void *) NLMSG_TAIL(&req.n) - (void *) tail;
 574
 575         msg_size = NLMSG_ALIGN(req.n.nlmsg_len) - NLMSG_ALIGN(sizeof(struct nlmsghdr));
 576
 577         if (event == RTM_GETACTION) {
 578                 if (rtnl_dump_request(&rth, event, (void *)&req.t, msg_size) < 0) {
 579                         perror("Cannot send dump request");
 580                         return 1;
 581                 }
 582                 ret = rtnl_dump_filter(&rth, print_action, stdout);
 583         }
 584
 585         if (event == RTM_DELACTION) {
 586                 req.n.nlmsg_len = NLMSG_ALIGN(req.n.nlmsg_len);
 587                 req.n.nlmsg_type = RTM_DELACTION;
 588                 req.n.nlmsg_flags |= NLM_F_ROOT;
 589                 req.n.nlmsg_flags |= NLM_F_REQUEST;
 590                 if (rtnl_talk(&rth, &req.n, NULL, 0) < 0) {
 591                         fprintf(stderr, "We have an error flushing\n");
 592                         return 1;
 593                 }
 594
 595         }
 596
 597 bad_val:
 598
 599         return ret;
 600 }
 601
 602 int do_action(int argc, char **argv)
 603 {
 604
 605         int ret = 0;
 606
 607         while (argc > 0) {
 608
 609                 if (matches(*argv, "add") == 0) {
 610                         ret =  tc_action_modify(RTM_NEWACTION, NLM_F_EXCL|NLM_F_CREATE, &argc, &argv);
 611                 } else if (matches(*argv, "change") == 0 ||
 612                           matches(*argv, "replace") == 0) {
 613                         ret = tc_action_modify(RTM_NEWACTION, NLM_F_CREATE|NLM_F_REPLACE, &argc, &argv);
 614                 } else if (matches(*argv, "delete") == 0) {
 615                         argc -=1;
 616                         argv +=1;
 617                         ret = tc_action_gd(RTM_DELACTION, 0,  &argc, &argv);
 618                 } else if (matches(*argv, "get") == 0) {
 619                         argc -=1;
 620                         argv +=1;
 621                         ret = tc_action_gd(RTM_GETACTION, 0,  &argc, &argv);
 622                 } else if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0
 623                                                 || matches(*argv, "lst") == 0) {
 624                         if (argc <= 2) {
 625                                 act_usage();
 626                                 return -1;
 627                         }
 628                         return tc_act_list_or_flush(argc-2, argv+2, RTM_GETACTION);
 629                 } else if (matches(*argv, "flush") == 0) {
 630                         if (argc <= 2) {
 631                                 act_usage();
 632                                 return -1;
 633                         }
 634                         return tc_act_list_or_flush(argc-2, argv+2, RTM_DELACTION);
 635                 } else if (matches(*argv, "help") == 0) {
 636                         act_usage();
 637                         return -1;
 638                 } else {
 639
 640                         ret = -1;
 641                 }
 642
 643                 if (ret < 0) {
 644                         fprintf(stderr, "Command \"%s\" is unknown, try \"tc actions help\".\n", *argv);
 645                         return -1;
 646                 }
 647         }
 648
 649         return 0;
 650 }
 651