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