lib/libnetlink.c

   1 /*
   2  * libnetlink.c RTnetlink service routines.
   3  *
   4  *              This program is free software; you can redistribute 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:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <syslog.h>
  17 #include <fcntl.h>
  18 #include <net/if_arp.h>
  19 #include <sys/socket.h>
  20 #include <netinet/in.h>
  21 #include <string.h>
  22 #include <errno.h>
  23 #include <time.h>
  24 #include <sys/uio.h>
  25
  26 #include "libnetlink.h"
  27
  28 #ifndef SOL_NETLINK
  29 #define SOL_NETLINK 270
  30 #endif
  31
  32 #ifndef MIN
  33 #define MIN(a, b) ((a) < (b) ? (a) : (b))
  34 #endif
  35
  36 int rcvbuf = 1024 * 1024;
  37
  38 void rtnl_close(struct rtnl_handle *rth)
  39 {
  40         if (rth->fd >= 0) {
  41                 close(rth->fd);
  42                 rth->fd = -1;
  43         }
  44 }
  45
  46 int rtnl_open_byproto(struct rtnl_handle *rth, unsigned subscriptions,
  47                       int protocol)
  48 {
  49         socklen_t addr_len;
  50         int sndbuf = 32768;
  51
  52         memset(rth, 0, sizeof(*rth));
  53
  54         rth->proto = protocol;
  55         rth->fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol);
  56         if (rth->fd < 0) {
  57                 perror("Cannot open netlink socket");
  58                 return -1;
  59         }
  60
  61         if (setsockopt(rth->fd,SOL_SOCKET,SO_SNDBUF,&sndbuf,sizeof(sndbuf)) < 0) {
  62                 perror("SO_SNDBUF");
  63                 return -1;
  64         }
  65
  66         if (setsockopt(rth->fd,SOL_SOCKET,SO_RCVBUF,&rcvbuf,sizeof(rcvbuf)) < 0) {
  67                 perror("SO_RCVBUF");
  68                 return -1;
  69         }
  70
  71         memset(&rth->local, 0, sizeof(rth->local));
  72         rth->local.nl_family = AF_NETLINK;
  73         rth->local.nl_groups = subscriptions;
  74
  75         if (bind(rth->fd, (struct sockaddr*)&rth->local, sizeof(rth->local)) < 0) {
  76                 perror("Cannot bind netlink socket");
  77                 return -1;
  78         }
  79         addr_len = sizeof(rth->local);
  80         if (getsockname(rth->fd, (struct sockaddr*)&rth->local, &addr_len) < 0) {
  81                 perror("Cannot getsockname");
  82                 return -1;
  83         }
  84         if (addr_len != sizeof(rth->local)) {
  85                 fprintf(stderr, "Wrong address length %d\n", addr_len);
  86                 return -1;
  87         }
  88         if (rth->local.nl_family != AF_NETLINK) {
  89                 fprintf(stderr, "Wrong address family %d\n", rth->local.nl_family);
  90                 return -1;
  91         }
  92         rth->seq = time(NULL);
  93         return 0;
  94 }
  95
  96 int rtnl_open(struct rtnl_handle *rth, unsigned subscriptions)
  97 {
  98         return rtnl_open_byproto(rth, subscriptions, NETLINK_ROUTE);
  99 }
 100
 101 int rtnl_wilddump_request(struct rtnl_handle *rth, int family, int type)
 102 {
 103         return rtnl_wilddump_req_filter(rth, family, type, RTEXT_FILTER_VF);
 104 }
 105
 106 int rtnl_wilddump_req_filter(struct rtnl_handle *rth, int family, int type,
 107                             __u32 filt_mask)
 108 {
 109         struct {
 110                 struct nlmsghdr nlh;
 111                 struct ifinfomsg ifm;
 112                 /* attribute has to be NLMSG aligned */
 113                 struct rtattr ext_req __attribute__ ((aligned(NLMSG_ALIGNTO)));
 114                 __u32 ext_filter_mask;
 115         } req = {
 116                 .nlh.nlmsg_len = sizeof(req),
 117                 .nlh.nlmsg_type = type,
 118                 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 119                 .nlh.nlmsg_seq = rth->dump = ++rth->seq,
 120                 .ifm.ifi_family = family,
 121                 .ext_req.rta_type = IFLA_EXT_MASK,
 122                 .ext_req.rta_len = RTA_LENGTH(sizeof(__u32)),
 123                 .ext_filter_mask = filt_mask,
 124         };
 125
 126         return send(rth->fd, (void*)&req, sizeof(req), 0);
 127 }
 128
 129 int rtnl_wilddump_req_filter_fn(struct rtnl_handle *rth, int family, int type,
 130                                 req_filter_fn_t filter_fn)
 131 {
 132         struct {
 133                 struct nlmsghdr nlh;
 134                 struct ifinfomsg ifm;
 135                 char buf[1024];
 136         } req = {
 137                 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
 138                 .nlh.nlmsg_type = type,
 139                 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 140                 .nlh.nlmsg_seq = rth->dump = ++rth->seq,
 141                 .ifm.ifi_family = family,
 142         };
 143         int err;
 144
 145         if (!filter_fn)
 146                 return -EINVAL;
 147
 148         err = filter_fn(&req.nlh, sizeof(req));
 149         if (err)
 150                 return err;
 151
 152         return send(rth->fd, (void*)&req, sizeof(req), 0);
 153 }
 154
 155 int rtnl_wilddump_stats_req_filter(struct rtnl_handle *rth, int fam, int type,
 156                                    __u32 filt_mask)
 157 {
 158         struct {
 159                 struct nlmsghdr nlh;
 160                 struct if_stats_msg ifsm;
 161         } req;
 162
 163         memset(&req, 0, sizeof(req));
 164         req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct if_stats_msg));
 165         req.nlh.nlmsg_type = type;
 166         req.nlh.nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
 167         req.nlh.nlmsg_pid = 0;
 168         req.nlh.nlmsg_seq = rth->dump = ++rth->seq;
 169         req.ifsm.family = fam;
 170         req.ifsm.filter_mask = filt_mask;
 171
 172         return send(rth->fd, (void *)&req, sizeof(req), 0);
 173 }
 174
 175 int rtnl_send(struct rtnl_handle *rth, const void *buf, int len)
 176 {
 177         return send(rth->fd, buf, len, 0);
 178 }
 179
 180 int rtnl_send_check(struct rtnl_handle *rth, const void *buf, int len)
 181 {
 182         struct nlmsghdr *h;
 183         int status;
 184         char resp[1024];
 185
 186         status = send(rth->fd, buf, len, 0);
 187         if (status < 0)
 188                 return status;
 189
 190         /* Check for immediate errors */
 191         status = recv(rth->fd, resp, sizeof(resp), MSG_DONTWAIT|MSG_PEEK);
 192         if (status < 0) {
 193                 if (errno == EAGAIN)
 194                         return 0;
 195                 return -1;
 196         }
 197
 198         for (h = (struct nlmsghdr *)resp; NLMSG_OK(h, status);
 199              h = NLMSG_NEXT(h, status)) {
 200                 if (h->nlmsg_type == NLMSG_ERROR) {
 201                         struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
 202                         if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr)))
 203                                 fprintf(stderr, "ERROR truncated\n");
 204                         else
 205                                 errno = -err->error;
 206                         return -1;
 207                 }
 208         }
 209
 210         return 0;
 211 }
 212
 213 int rtnl_dump_request(struct rtnl_handle *rth, int type, void *req, int len)
 214 {
 215         struct nlmsghdr nlh = {
 216                 .nlmsg_len = NLMSG_LENGTH(len),
 217                 .nlmsg_type = type,
 218                 .nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
 219                 .nlmsg_seq = rth->dump = ++rth->seq,
 220         };
 221         struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
 222         struct iovec iov[2] = {
 223                 { .iov_base = &nlh, .iov_len = sizeof(nlh) },
 224                 { .iov_base = req, .iov_len = len }
 225         };
 226         struct msghdr msg = {
 227                 .msg_name = &nladdr,
 228                 .msg_namelen = sizeof(nladdr),
 229                 .msg_iov = iov,
 230                 .msg_iovlen = 2,
 231         };
 232
 233         return sendmsg(rth->fd, &msg, 0);
 234 }
 235
 236 int rtnl_dump_request_n(struct rtnl_handle *rth, struct nlmsghdr *n)
 237 {
 238         struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
 239         struct iovec iov = {
 240                 .iov_base = (void*) n,
 241                 .iov_len = n->nlmsg_len
 242         };
 243         struct msghdr msg = {
 244                 .msg_name = &nladdr,
 245                 .msg_namelen = sizeof(nladdr),
 246                 .msg_iov = &iov,
 247                 .msg_iovlen = 1,
 248         };
 249
 250         n->nlmsg_flags = NLM_F_DUMP|NLM_F_REQUEST;
 251         n->nlmsg_pid = 0;
 252         n->nlmsg_seq = rth->dump = ++rth->seq;
 253
 254         return sendmsg(rth->fd, &msg, 0);
 255 }
 256
 257 int rtnl_dump_filter_l(struct rtnl_handle *rth,
 258                        const struct rtnl_dump_filter_arg *arg)
 259 {
 260         struct sockaddr_nl nladdr;
 261         struct iovec iov;
 262         struct msghdr msg = {
 263                 .msg_name = &nladdr,
 264                 .msg_namelen = sizeof(nladdr),
 265                 .msg_iov = &iov,
 266                 .msg_iovlen = 1,
 267         };
 268         char buf[32768];
 269         int dump_intr = 0;
 270
 271         iov.iov_base = buf;
 272         while (1) {
 273                 int status;
 274                 const struct rtnl_dump_filter_arg *a;
 275                 int found_done = 0;
 276                 int msglen = 0;
 277
 278                 iov.iov_len = sizeof(buf);
 279                 status = recvmsg(rth->fd, &msg, 0);
 280
 281                 if (status < 0) {
 282                         if (errno == EINTR || errno == EAGAIN)
 283                                 continue;
 284                         fprintf(stderr, "netlink receive error %s (%d)\n",
 285                                 strerror(errno), errno);
 286                         return -1;
 287                 }
 288
 289                 if (status == 0) {
 290                         fprintf(stderr, "EOF on netlink\n");
 291                         return -1;
 292                 }
 293
 294                 if (rth->dump_fp)
 295                         fwrite(buf, 1, NLMSG_ALIGN(status), rth->dump_fp);
 296
 297                 for (a = arg; a->filter; a++) {
 298                         struct nlmsghdr *h = (struct nlmsghdr*)buf;
 299                         msglen = status;
 300
 301                         while (NLMSG_OK(h, msglen)) {
 302                                 int err = 0;
 303
 304                                 h->nlmsg_flags &= ~a->nc_flags;
 305
 306                                 if (nladdr.nl_pid != 0 ||
 307                                     h->nlmsg_pid != rth->local.nl_pid ||
 308                                     h->nlmsg_seq != rth->dump)
 309                                         goto skip_it;
 310
 311                                 if (h->nlmsg_flags & NLM_F_DUMP_INTR)
 312                                         dump_intr = 1;
 313
 314                                 if (h->nlmsg_type == NLMSG_DONE) {
 315                                         found_done = 1;
 316                                         break; /* process next filter */
 317                                 }
 318                                 if (h->nlmsg_type == NLMSG_ERROR) {
 319                                         struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
 320                                         if (h->nlmsg_len < NLMSG_LENGTH(sizeof(struct nlmsgerr))) {
 321                                                 fprintf(stderr,
 322                                                         "ERROR truncated\n");
 323                                         } else {
 324                                                 errno = -err->error;
 325                                                 if (rth->proto == NETLINK_SOCK_DIAG &&
 326                                                     (errno == ENOENT ||
 327                                                      errno == EOPNOTSUPP))
 328                                                         return -1;
 329
 330                                                 perror("RTNETLINK answers");
 331                                         }
 332                                         return -1;
 333                                 }
 334
 335                                 if (!rth->dump_fp) {
 336                                         err = a->filter(&nladdr, h, a->arg1);
 337                                         if (err < 0)
 338                                                 return err;
 339                                 }
 340
 341 skip_it:
 342                                 h = NLMSG_NEXT(h, msglen);
 343                         }
 344                 }
 345
 346                 if (found_done) {
 347                         if (dump_intr)
 348                                 fprintf(stderr,
 349                                         "Dump was interrupted and may be inconsistent.\n");
 350                         return 0;
 351                 }
 352
 353                 if (msg.msg_flags & MSG_TRUNC) {
 354                         fprintf(stderr, "Message truncated\n");
 355                         continue;
 356                 }
 357                 if (msglen) {
 358                         fprintf(stderr, "!!!Remnant of size %d\n", msglen);
 359                         exit(1);
 360                 }
 361         }
 362 }
 363
 364 int rtnl_dump_filter_nc(struct rtnl_handle *rth,
 365                      rtnl_filter_t filter,
 366                      void *arg1, __u16 nc_flags)
 367 {
 368         const struct rtnl_dump_filter_arg a[2] = {
 369                 { .filter = filter, .arg1 = arg1, .nc_flags = nc_flags, },
 370                 { .filter = NULL,   .arg1 = NULL, .nc_flags = 0, },
 371         };
 372
 373         return rtnl_dump_filter_l(rth, a);
 374 }
 375
 376 int rtnl_talk(struct rtnl_handle *rtnl, struct nlmsghdr *n,
 377               struct nlmsghdr *answer, size_t maxlen)
 378 {
 379         int status;
 380         unsigned seq;
 381         struct nlmsghdr *h;
 382         struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
 383         struct iovec iov = {
 384                 .iov_base = (void*) n,
 385                 .iov_len = n->nlmsg_len
 386         };
 387         struct msghdr msg = {
 388                 .msg_name = &nladdr,
 389                 .msg_namelen = sizeof(nladdr),
 390                 .msg_iov = &iov,
 391                 .msg_iovlen = 1,
 392         };
 393         char   buf[32768] = {};
 394
 395         n->nlmsg_seq = seq = ++rtnl->seq;
 396
 397         if (answer == NULL)
 398                 n->nlmsg_flags |= NLM_F_ACK;
 399
 400         status = sendmsg(rtnl->fd, &msg, 0);
 401         if (status < 0) {
 402                 perror("Cannot talk to rtnetlink");
 403                 return -1;
 404         }
 405
 406         iov.iov_base = buf;
 407         while (1) {
 408                 iov.iov_len = sizeof(buf);
 409                 status = recvmsg(rtnl->fd, &msg, 0);
 410
 411                 if (status < 0) {
 412                         if (errno == EINTR || errno == EAGAIN)
 413                                 continue;
 414                         fprintf(stderr, "netlink receive error %s (%d)\n",
 415                                 strerror(errno), errno);
 416                         return -1;
 417                 }
 418                 if (status == 0) {
 419                         fprintf(stderr, "EOF on netlink\n");
 420                         return -1;
 421                 }
 422                 if (msg.msg_namelen != sizeof(nladdr)) {
 423                         fprintf(stderr, "sender address length == %d\n", msg.msg_namelen);
 424                         exit(1);
 425                 }
 426                 for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
 427                         int len = h->nlmsg_len;
 428                         int l = len - sizeof(*h);
 429
 430                         if (l < 0 || len>status) {
 431                                 if (msg.msg_flags & MSG_TRUNC) {
 432                                         fprintf(stderr, "Truncated message\n");
 433                                         return -1;
 434                                 }
 435                                 fprintf(stderr, "!!!malformed message: len=%d\n", len);
 436                                 exit(1);
 437                         }
 438
 439                         if (nladdr.nl_pid != 0 ||
 440                             h->nlmsg_pid != rtnl->local.nl_pid ||
 441                             h->nlmsg_seq != seq) {
 442                                 /* Don't forget to skip that message. */
 443                                 status -= NLMSG_ALIGN(len);
 444                                 h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
 445                                 continue;
 446                         }
 447
 448                         if (h->nlmsg_type == NLMSG_ERROR) {
 449                                 struct nlmsgerr *err = (struct nlmsgerr*)NLMSG_DATA(h);
 450                                 if (l < sizeof(struct nlmsgerr)) {
 451                                         fprintf(stderr, "ERROR truncated\n");
 452                                 } else if (!err->error) {
 453                                         if (answer)
 454                                                 memcpy(answer, h,
 455                                                        MIN(maxlen, h->nlmsg_len));
 456                                         return 0;
 457                                 }
 458
 459                                 if (rtnl->proto != NETLINK_SOCK_DIAG)
 460                                         fprintf(stderr,
 461                                                 "RTNETLINK answers: %s\n",
 462                                                 strerror(-err->error));
 463                                 errno = -err->error;
 464                                 return -1;
 465                         }
 466
 467                         if (answer) {
 468                                 memcpy(answer, h,
 469                                        MIN(maxlen, h->nlmsg_len));
 470                                 return 0;
 471                         }
 472
 473                         fprintf(stderr, "Unexpected reply!!!\n");
 474
 475                         status -= NLMSG_ALIGN(len);
 476                         h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
 477                 }
 478
 479                 if (msg.msg_flags & MSG_TRUNC) {
 480                         fprintf(stderr, "Message truncated\n");
 481                         continue;
 482                 }
 483
 484                 if (status) {
 485                         fprintf(stderr, "!!!Remnant of size %d\n", status);
 486                         exit(1);
 487                 }
 488         }
 489 }
 490
 491 int rtnl_listen_all_nsid(struct rtnl_handle *rth)
 492 {
 493         unsigned int on = 1;
 494
 495         if (setsockopt(rth->fd, SOL_NETLINK, NETLINK_LISTEN_ALL_NSID, &on,
 496                        sizeof(on)) < 0) {
 497                 perror("NETLINK_LISTEN_ALL_NSID");
 498                 return -1;
 499         }
 500         rth->flags |= RTNL_HANDLE_F_LISTEN_ALL_NSID;
 501         return 0;
 502 }
 503
 504 int rtnl_listen(struct rtnl_handle *rtnl,
 505                 rtnl_listen_filter_t handler,
 506                 void *jarg)
 507 {
 508         int status;
 509         struct nlmsghdr *h;
 510         struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
 511         struct iovec iov;
 512         struct msghdr msg = {
 513                 .msg_name = &nladdr,
 514                 .msg_namelen = sizeof(nladdr),
 515                 .msg_iov = &iov,
 516                 .msg_iovlen = 1,
 517         };
 518         char   buf[16384];
 519         char   cmsgbuf[BUFSIZ];
 520
 521         if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
 522                 msg.msg_control = &cmsgbuf;
 523                 msg.msg_controllen = sizeof(cmsgbuf);
 524         }
 525
 526         iov.iov_base = buf;
 527         while (1) {
 528                 struct rtnl_ctrl_data ctrl;
 529                 struct cmsghdr *cmsg;
 530
 531                 iov.iov_len = sizeof(buf);
 532                 status = recvmsg(rtnl->fd, &msg, 0);
 533
 534                 if (status < 0) {
 535                         if (errno == EINTR || errno == EAGAIN)
 536                                 continue;
 537                         fprintf(stderr, "netlink receive error %s (%d)\n",
 538                                 strerror(errno), errno);
 539                         if (errno == ENOBUFS)
 540                                 continue;
 541                         return -1;
 542                 }
 543                 if (status == 0) {
 544                         fprintf(stderr, "EOF on netlink\n");
 545                         return -1;
 546                 }
 547                 if (msg.msg_namelen != sizeof(nladdr)) {
 548                         fprintf(stderr, "Sender address length == %d\n", msg.msg_namelen);
 549                         exit(1);
 550                 }
 551
 552                 if (rtnl->flags & RTNL_HANDLE_F_LISTEN_ALL_NSID) {
 553                         memset(&ctrl, 0, sizeof(ctrl));
 554                         ctrl.nsid = -1;
 555                         for (cmsg = CMSG_FIRSTHDR(&msg); cmsg;
 556                              cmsg = CMSG_NXTHDR(&msg, cmsg))
 557                                 if (cmsg->cmsg_level == SOL_NETLINK &&
 558                                     cmsg->cmsg_type == NETLINK_LISTEN_ALL_NSID &&
 559                                     cmsg->cmsg_len == CMSG_LEN(sizeof(int))) {
 560                                         int *data = (int *)CMSG_DATA(cmsg);
 561
 562                                         ctrl.nsid = *data;
 563                                 }
 564                 }
 565
 566                 for (h = (struct nlmsghdr*)buf; status >= sizeof(*h); ) {
 567                         int err;
 568                         int len = h->nlmsg_len;
 569                         int l = len - sizeof(*h);
 570
 571                         if (l<0 || len>status) {
 572                                 if (msg.msg_flags & MSG_TRUNC) {
 573                                         fprintf(stderr, "Truncated message\n");
 574                                         return -1;
 575                                 }
 576                                 fprintf(stderr, "!!!malformed message: len=%d\n", len);
 577                                 exit(1);
 578                         }
 579
 580                         err = handler(&nladdr, &ctrl, h, jarg);
 581                         if (err < 0)
 582                                 return err;
 583
 584                         status -= NLMSG_ALIGN(len);
 585                         h = (struct nlmsghdr*)((char*)h + NLMSG_ALIGN(len));
 586                 }
 587                 if (msg.msg_flags & MSG_TRUNC) {
 588                         fprintf(stderr, "Message truncated\n");
 589                         continue;
 590                 }
 591                 if (status) {
 592                         fprintf(stderr, "!!!Remnant of size %d\n", status);
 593                         exit(1);
 594                 }
 595         }
 596 }
 597
 598 int rtnl_from_file(FILE *rtnl, rtnl_listen_filter_t handler,
 599                    void *jarg)
 600 {
 601         int status;
 602         struct sockaddr_nl nladdr = { .nl_family = AF_NETLINK };
 603         char   buf[16384];
 604         struct nlmsghdr *h = (void*)buf;
 605
 606         while (1) {
 607                 int err, len;
 608                 int l;
 609
 610                 status = fread(&buf, 1, sizeof(*h), rtnl);
 611
 612                 if (status < 0) {
 613                         if (errno == EINTR)
 614                                 continue;
 615                         perror("rtnl_from_file: fread");
 616                         return -1;
 617                 }
 618                 if (status == 0)
 619                         return 0;
 620
 621                 len = h->nlmsg_len;
 622                 l = len - sizeof(*h);
 623
 624                 if (l<0 || len>sizeof(buf)) {
 625                         fprintf(stderr, "!!!malformed message: len=%d @%lu\n",
 626                                 len, ftell(rtnl));
 627                         return -1;
 628                 }
 629
 630                 status = fread(NLMSG_DATA(h), 1, NLMSG_ALIGN(l), rtnl);
 631
 632                 if (status < 0) {
 633                         perror("rtnl_from_file: fread");
 634                         return -1;
 635                 }
 636                 if (status < l) {
 637                         fprintf(stderr, "rtnl-from_file: truncated message\n");
 638                         return -1;
 639                 }
 640
 641                 err = handler(&nladdr, NULL, h, jarg);
 642                 if (err < 0)
 643                         return err;
 644         }
 645 }
 646
 647 int addattr(struct nlmsghdr *n, int maxlen, int type)
 648 {
 649         return addattr_l(n, maxlen, type, NULL, 0);
 650 }
 651
 652 int addattr8(struct nlmsghdr *n, int maxlen, int type, __u8 data)
 653 {
 654         return addattr_l(n, maxlen, type, &data, sizeof(__u8));
 655 }
 656
 657 int addattr16(struct nlmsghdr *n, int maxlen, int type, __u16 data)
 658 {
 659         return addattr_l(n, maxlen, type, &data, sizeof(__u16));
 660 }
 661
 662 int addattr32(struct nlmsghdr *n, int maxlen, int type, __u32 data)
 663 {
 664         return addattr_l(n, maxlen, type, &data, sizeof(__u32));
 665 }
 666
 667 int addattr64(struct nlmsghdr *n, int maxlen, int type, __u64 data)
 668 {
 669         return addattr_l(n, maxlen, type, &data, sizeof(__u64));
 670 }
 671
 672 int addattrstrz(struct nlmsghdr *n, int maxlen, int type, const char *str)
 673 {
 674         return addattr_l(n, maxlen, type, str, strlen(str)+1);
 675 }
 676
 677 int addattr_l(struct nlmsghdr *n, int maxlen, int type, const void *data,
 678               int alen)
 679 {
 680         int len = RTA_LENGTH(alen);
 681         struct rtattr *rta;
 682
 683         if (NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len) > maxlen) {
 684                 fprintf(stderr, "addattr_l ERROR: message exceeded bound of %d\n",maxlen);
 685                 return -1;
 686         }
 687         rta = NLMSG_TAIL(n);
 688         rta->rta_type = type;
 689         rta->rta_len = len;
 690         memcpy(RTA_DATA(rta), data, alen);
 691         n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
 692         return 0;
 693 }
 694
 695 int addraw_l(struct nlmsghdr *n, int maxlen, const void *data, int len)
 696 {
 697         if (NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len) > maxlen) {
 698                 fprintf(stderr, "addraw_l ERROR: message exceeded bound of %d\n",maxlen);
 699                 return -1;
 700         }
 701
 702         memcpy(NLMSG_TAIL(n), data, len);
 703         memset((void *) NLMSG_TAIL(n) + len, 0, NLMSG_ALIGN(len) - len);
 704         n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + NLMSG_ALIGN(len);
 705         return 0;
 706 }
 707
 708 struct rtattr *addattr_nest(struct nlmsghdr *n, int maxlen, int type)
 709 {
 710         struct rtattr *nest = NLMSG_TAIL(n);
 711
 712         addattr_l(n, maxlen, type, NULL, 0);
 713         return nest;
 714 }
 715
 716 int addattr_nest_end(struct nlmsghdr *n, struct rtattr *nest)
 717 {
 718         nest->rta_len = (void *)NLMSG_TAIL(n) - (void *)nest;
 719         return n->nlmsg_len;
 720 }
 721
 722 struct rtattr *addattr_nest_compat(struct nlmsghdr *n, int maxlen, int type,
 723                                    const void *data, int len)
 724 {
 725         struct rtattr *start = NLMSG_TAIL(n);
 726
 727         addattr_l(n, maxlen, type, data, len);
 728         addattr_nest(n, maxlen, type);
 729         return start;
 730 }
 731
 732 int addattr_nest_compat_end(struct nlmsghdr *n, struct rtattr *start)
 733 {
 734         struct rtattr *nest = (void *)start + NLMSG_ALIGN(start->rta_len);
 735
 736         start->rta_len = (void *)NLMSG_TAIL(n) - (void *)start;
 737         addattr_nest_end(n, nest);
 738         return n->nlmsg_len;
 739 }
 740
 741 int rta_addattr32(struct rtattr *rta, int maxlen, int type, __u32 data)
 742 {
 743         int len = RTA_LENGTH(4);
 744         struct rtattr *subrta;
 745
 746         if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
 747                 fprintf(stderr,"rta_addattr32: Error! max allowed bound %d exceeded\n",maxlen);
 748                 return -1;
 749         }
 750         subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
 751         subrta->rta_type = type;
 752         subrta->rta_len = len;
 753         memcpy(RTA_DATA(subrta), &data, 4);
 754         rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
 755         return 0;
 756 }
 757
 758 int rta_addattr_l(struct rtattr *rta, int maxlen, int type,
 759                   const void *data, int alen)
 760 {
 761         struct rtattr *subrta;
 762         int len = RTA_LENGTH(alen);
 763
 764         if (RTA_ALIGN(rta->rta_len) + RTA_ALIGN(len) > maxlen) {
 765                 fprintf(stderr,"rta_addattr_l: Error! max allowed bound %d exceeded\n",maxlen);
 766                 return -1;
 767         }
 768         subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
 769         subrta->rta_type = type;
 770         subrta->rta_len = len;
 771         memcpy(RTA_DATA(subrta), data, alen);
 772         rta->rta_len = NLMSG_ALIGN(rta->rta_len) + RTA_ALIGN(len);
 773         return 0;
 774 }
 775
 776 int rta_addattr8(struct rtattr *rta, int maxlen, int type, __u8 data)
 777 {
 778         return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u8));
 779 }
 780
 781 int rta_addattr16(struct rtattr *rta, int maxlen, int type, __u16 data)
 782 {
 783         return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u16));
 784 }
 785
 786 int rta_addattr64(struct rtattr *rta, int maxlen, int type, __u64 data)
 787 {
 788         return rta_addattr_l(rta, maxlen, type, &data, sizeof(__u64));
 789 }
 790
 791 struct rtattr *rta_nest(struct rtattr *rta, int maxlen, int type)
 792 {
 793         struct rtattr *nest = RTA_TAIL(rta);
 794
 795         rta_addattr_l(rta, maxlen, type, NULL, 0);
 796
 797         return nest;
 798 }
 799
 800 int rta_nest_end(struct rtattr *rta, struct rtattr *nest)
 801 {
 802         nest->rta_len = (void *)RTA_TAIL(rta) - (void *)nest;
 803
 804         return rta->rta_len;
 805 }
 806
 807 int parse_rtattr(struct rtattr *tb[], int max, struct rtattr *rta, int len)
 808 {
 809         return parse_rtattr_flags(tb, max, rta, len, 0);
 810 }
 811
 812 int parse_rtattr_flags(struct rtattr *tb[], int max, struct rtattr *rta,
 813                        int len, unsigned short flags)
 814 {
 815         unsigned short type;
 816
 817         memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
 818         while (RTA_OK(rta, len)) {
 819                 type = rta->rta_type & ~flags;
 820                 if ((type <= max) && (!tb[type]))
 821                         tb[type] = rta;
 822                 rta = RTA_NEXT(rta,len);
 823         }
 824         if (len)
 825                 fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
 826         return 0;
 827 }
 828
 829 int parse_rtattr_byindex(struct rtattr *tb[], int max, struct rtattr *rta, int len)
 830 {
 831         int i = 0;
 832
 833         memset(tb, 0, sizeof(struct rtattr *) * max);
 834         while (RTA_OK(rta, len)) {
 835                 if (rta->rta_type <= max && i < max)
 836                         tb[i++] = rta;
 837                 rta = RTA_NEXT(rta,len);
 838         }
 839         if (len)
 840                 fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
 841         return i;
 842 }
 843
 844 struct rtattr *parse_rtattr_one(int type, struct rtattr *rta, int len)
 845 {
 846         while (RTA_OK(rta, len)) {
 847                 if (rta->rta_type == type)
 848                         return rta;
 849                 rta = RTA_NEXT(rta, len);
 850         }
 851         if (len)
 852                 fprintf(stderr, "!!!Deficit %d, rta_len=%d\n", len, rta->rta_len);
 853         return NULL;
 854 }
 855
 856 int __parse_rtattr_nested_compat(struct rtattr *tb[], int max, struct rtattr *rta,
 857                                  int len)
 858 {
 859         if (RTA_PAYLOAD(rta) < len)
 860                 return -1;
 861         if (RTA_PAYLOAD(rta) >= RTA_ALIGN(len) + sizeof(struct rtattr)) {
 862                 rta = RTA_DATA(rta) + RTA_ALIGN(len);
 863                 return parse_rtattr_nested(tb, max, rta);
 864         }
 865         memset(tb, 0, sizeof(struct rtattr *) * (max + 1));
 866         return 0;
 867 }