ip/link_gre6.c

   1 /*
   2  * link_gre6.c  gre driver module
   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:     Dmitry Kozlov <xeb@mail.ru>
  10  *
  11  */
  12
  13 #include <string.h>
  14 #include <net/if.h>
  15 #include <sys/types.h>
  16 #include <sys/socket.h>
  17 #include <arpa/inet.h>
  18
  19 #include <linux/ip.h>
  20 #include <linux/if_tunnel.h>
  21 #include <linux/ip6_tunnel.h>
  22
  23 #include "rt_names.h"
  24 #include "utils.h"
  25 #include "ip_common.h"
  26 #include "tunnel.h"
  27
  28 #define IP6_FLOWINFO_TCLASS     htonl(0x0FF00000)
  29 #define IP6_FLOWINFO_FLOWLABEL  htonl(0x000FFFFF)
  30
  31 #define DEFAULT_TNL_HOP_LIMIT   (64)
  32
  33 static void print_usage(FILE *f)
  34 {
  35         fprintf(f, "Usage: ip link { add | set | change | replace | del } NAME\n");
  36         fprintf(f, "          type { ip6gre | ip6gretap } [ remote ADDR ] [ local ADDR ]\n");
  37         fprintf(f, "          [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
  38         fprintf(f, "          [ hoplimit TTL ] [ encaplimit ELIM ]\n");
  39         fprintf(f, "          [ tclass TCLASS ] [ flowlabel FLOWLABEL ]\n");
  40         fprintf(f, "          [ dscp inherit ] [ dev PHYS_DEV ]\n");
  41         fprintf(f, "\n");
  42         fprintf(f, "Where: NAME      := STRING\n");
  43         fprintf(f, "       ADDR      := IPV6_ADDRESS\n");
  44         fprintf(f, "       TTL       := { 0..255 } (default=%d)\n",
  45                 DEFAULT_TNL_HOP_LIMIT);
  46         fprintf(f, "       KEY       := { DOTTED_QUAD | NUMBER }\n");
  47         fprintf(f, "       ELIM      := { none | 0..255 }(default=%d)\n",
  48                 IPV6_DEFAULT_TNL_ENCAP_LIMIT);
  49         fprintf(f, "       TCLASS    := { 0x0..0xff | inherit }\n");
  50         fprintf(f, "       FLOWLABEL := { 0x0..0xfffff | inherit }\n");
  51 }
  52
  53 static void usage(void) __attribute__((noreturn));
  54 static void usage(void)
  55 {
  56         print_usage(stderr);
  57         exit(-1);
  58 }
  59
  60 static int gre_parse_opt(struct link_util *lu, int argc, char **argv,
  61                          struct nlmsghdr *n)
  62 {
  63         struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1);
  64         struct {
  65                 struct nlmsghdr n;
  66                 struct ifinfomsg i;
  67                 char buf[1024];
  68         } req = {
  69                 .n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi)),
  70                 .n.nlmsg_flags = NLM_F_REQUEST,
  71                 .n.nlmsg_type = RTM_GETLINK,
  72                 .i.ifi_family = preferred_family,
  73                 .i.ifi_index = ifi->ifi_index,
  74         };
  75         struct rtattr *tb[IFLA_MAX + 1];
  76         struct rtattr *linkinfo[IFLA_INFO_MAX+1];
  77         struct rtattr *greinfo[IFLA_GRE_MAX + 1];
  78         __u16 iflags = 0;
  79         __u16 oflags = 0;
  80         unsigned int ikey = 0;
  81         unsigned int okey = 0;
  82         struct in6_addr raddr = IN6ADDR_ANY_INIT;
  83         struct in6_addr laddr = IN6ADDR_ANY_INIT;
  84         unsigned int link = 0;
  85         unsigned int flowinfo = 0;
  86         unsigned int flags = 0;
  87         __u8 hop_limit = DEFAULT_TNL_HOP_LIMIT;
  88         __u8 encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
  89         int len;
  90
  91         if (!(n->nlmsg_flags & NLM_F_CREATE)) {
  92                 if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {
  93 get_failed:
  94                         fprintf(stderr,
  95                                 "Failed to get existing tunnel info.\n");
  96                         return -1;
  97                 }
  98
  99                 len = req.n.nlmsg_len;
 100                 len -= NLMSG_LENGTH(sizeof(*ifi));
 101                 if (len < 0)
 102                         goto get_failed;
 103
 104                 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len);
 105
 106                 if (!tb[IFLA_LINKINFO])
 107                         goto get_failed;
 108
 109                 parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 110
 111                 if (!linkinfo[IFLA_INFO_DATA])
 112                         goto get_failed;
 113
 114                 parse_rtattr_nested(greinfo, IFLA_GRE_MAX,
 115                                     linkinfo[IFLA_INFO_DATA]);
 116
 117                 if (greinfo[IFLA_GRE_IKEY])
 118                         ikey = rta_getattr_u32(greinfo[IFLA_GRE_IKEY]);
 119
 120                 if (greinfo[IFLA_GRE_OKEY])
 121                         okey = rta_getattr_u32(greinfo[IFLA_GRE_OKEY]);
 122
 123                 if (greinfo[IFLA_GRE_IFLAGS])
 124                         iflags = rta_getattr_u16(greinfo[IFLA_GRE_IFLAGS]);
 125
 126                 if (greinfo[IFLA_GRE_OFLAGS])
 127                         oflags = rta_getattr_u16(greinfo[IFLA_GRE_OFLAGS]);
 128
 129                 if (greinfo[IFLA_GRE_LOCAL])
 130                         memcpy(&laddr, RTA_DATA(greinfo[IFLA_GRE_LOCAL]), sizeof(laddr));
 131
 132                 if (greinfo[IFLA_GRE_REMOTE])
 133                         memcpy(&raddr, RTA_DATA(greinfo[IFLA_GRE_REMOTE]), sizeof(raddr));
 134
 135                 if (greinfo[IFLA_GRE_TTL])
 136                         hop_limit = rta_getattr_u8(greinfo[IFLA_GRE_TTL]);
 137
 138                 if (greinfo[IFLA_GRE_LINK])
 139                         link = rta_getattr_u32(greinfo[IFLA_GRE_LINK]);
 140
 141                 if (greinfo[IFLA_GRE_ENCAP_LIMIT])
 142                         encap_limit = rta_getattr_u8(greinfo[IFLA_GRE_ENCAP_LIMIT]);
 143
 144                 if (greinfo[IFLA_GRE_FLOWINFO])
 145                         flowinfo = rta_getattr_u32(greinfo[IFLA_GRE_FLOWINFO]);
 146
 147                 if (greinfo[IFLA_GRE_FLAGS])
 148                         flags = rta_getattr_u32(greinfo[IFLA_GRE_FLAGS]);
 149         }
 150
 151         while (argc > 0) {
 152                 if (!matches(*argv, "key")) {
 153                         unsigned int uval;
 154
 155                         NEXT_ARG();
 156                         iflags |= GRE_KEY;
 157                         oflags |= GRE_KEY;
 158                         if (strchr(*argv, '.'))
 159                                 uval = get_addr32(*argv);
 160                         else {
 161                                 if (get_unsigned(&uval, *argv, 0) < 0) {
 162                                         fprintf(stderr,
 163                                                 "Invalid value for \"key\"\n");
 164                                         exit(-1);
 165                                 }
 166                                 uval = htonl(uval);
 167                         }
 168
 169                         ikey = okey = uval;
 170                 } else if (!matches(*argv, "ikey")) {
 171                         unsigned int uval;
 172
 173                         NEXT_ARG();
 174                         iflags |= GRE_KEY;
 175                         if (strchr(*argv, '.'))
 176                                 uval = get_addr32(*argv);
 177                         else {
 178                                 if (get_unsigned(&uval, *argv, 0) < 0) {
 179                                         fprintf(stderr, "invalid value of \"ikey\"\n");
 180                                         exit(-1);
 181                                 }
 182                                 uval = htonl(uval);
 183                         }
 184                         ikey = uval;
 185                 } else if (!matches(*argv, "okey")) {
 186                         unsigned int uval;
 187
 188                         NEXT_ARG();
 189                         oflags |= GRE_KEY;
 190                         if (strchr(*argv, '.'))
 191                                 uval = get_addr32(*argv);
 192                         else {
 193                                 if (get_unsigned(&uval, *argv, 0) < 0) {
 194                                         fprintf(stderr, "invalid value of \"okey\"\n");
 195                                         exit(-1);
 196                                 }
 197                                 uval = htonl(uval);
 198                         }
 199                         okey = uval;
 200                 } else if (!matches(*argv, "seq")) {
 201                         iflags |= GRE_SEQ;
 202                         oflags |= GRE_SEQ;
 203                 } else if (!matches(*argv, "iseq")) {
 204                         iflags |= GRE_SEQ;
 205                 } else if (!matches(*argv, "oseq")) {
 206                         oflags |= GRE_SEQ;
 207                 } else if (!matches(*argv, "csum")) {
 208                         iflags |= GRE_CSUM;
 209                         oflags |= GRE_CSUM;
 210                 } else if (!matches(*argv, "icsum")) {
 211                         iflags |= GRE_CSUM;
 212                 } else if (!matches(*argv, "ocsum")) {
 213                         oflags |= GRE_CSUM;
 214                 } else if (!matches(*argv, "remote")) {
 215                         inet_prefix addr;
 216
 217                         NEXT_ARG();
 218                         get_prefix(&addr, *argv, preferred_family);
 219                         if (addr.family == AF_UNSPEC)
 220                                 invarg("\"remote\" address family is AF_UNSPEC", *argv);
 221                         memcpy(&raddr, &addr.data, sizeof(raddr));
 222                 } else if (!matches(*argv, "local")) {
 223                         inet_prefix addr;
 224
 225                         NEXT_ARG();
 226                         get_prefix(&addr, *argv, preferred_family);
 227                         if (addr.family == AF_UNSPEC)
 228                                 invarg("\"local\" address family is AF_UNSPEC", *argv);
 229                         memcpy(&laddr, &addr.data, sizeof(laddr));
 230                 } else if (!matches(*argv, "dev")) {
 231                         NEXT_ARG();
 232                         link = if_nametoindex(*argv);
 233                         if (link == 0) {
 234                                 fprintf(stderr, "Cannot find device \"%s\"\n",
 235                                         *argv);
 236                                 exit(-1);
 237                         }
 238                 } else if (!matches(*argv, "ttl") ||
 239                            !matches(*argv, "hoplimit")) {
 240                         __u8 uval;
 241
 242                         NEXT_ARG();
 243                         if (get_u8(&uval, *argv, 0))
 244                                 invarg("invalid TTL", *argv);
 245                         hop_limit = uval;
 246                 } else if (!matches(*argv, "tos") ||
 247                            !matches(*argv, "tclass") ||
 248                            !matches(*argv, "dsfield")) {
 249                         __u8 uval;
 250
 251                         NEXT_ARG();
 252                         if (strcmp(*argv, "inherit") == 0)
 253                                 flags |= IP6_TNL_F_USE_ORIG_TCLASS;
 254                         else {
 255                                 if (get_u8(&uval, *argv, 16))
 256                                         invarg("invalid TClass", *argv);
 257                                 flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
 258                                 flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
 259                         }
 260                 } else if (strcmp(*argv, "flowlabel") == 0 ||
 261                            strcmp(*argv, "fl") == 0) {
 262                         __u32 uval;
 263
 264                         NEXT_ARG();
 265                         if (strcmp(*argv, "inherit") == 0)
 266                                 flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
 267                         else {
 268                                 if (get_u32(&uval, *argv, 16))
 269                                         invarg("invalid Flowlabel", *argv);
 270                                 if (uval > 0xFFFFF)
 271                                         invarg("invalid Flowlabel", *argv);
 272                                 flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
 273                                 flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
 274                         }
 275                 } else if (strcmp(*argv, "dscp") == 0) {
 276                         NEXT_ARG();
 277                         if (strcmp(*argv, "inherit") != 0)
 278                                 invarg("not inherit", *argv);
 279                         flags |= IP6_TNL_F_RCV_DSCP_COPY;
 280                 } else
 281                         usage();
 282                 argc--; argv++;
 283         }
 284
 285         addattr32(n, 1024, IFLA_GRE_IKEY, ikey);
 286         addattr32(n, 1024, IFLA_GRE_OKEY, okey);
 287         addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2);
 288         addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2);
 289         addattr_l(n, 1024, IFLA_GRE_LOCAL, &laddr, sizeof(laddr));
 290         addattr_l(n, 1024, IFLA_GRE_REMOTE, &raddr, sizeof(raddr));
 291         if (link)
 292                 addattr32(n, 1024, IFLA_GRE_LINK, link);
 293         addattr_l(n, 1024, IFLA_GRE_TTL, &hop_limit, 1);
 294         addattr_l(n, 1024, IFLA_GRE_ENCAP_LIMIT, &encap_limit, 1);
 295         addattr_l(n, 1024, IFLA_GRE_FLOWINFO, &flowinfo, 4);
 296         addattr_l(n, 1024, IFLA_GRE_FLAGS, &flowinfo, 4);
 297
 298         return 0;
 299 }
 300
 301 static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 302 {
 303         char s2[64];
 304         const char *local = "any";
 305         const char *remote = "any";
 306         unsigned int iflags = 0;
 307         unsigned int oflags = 0;
 308         unsigned int flags = 0;
 309         unsigned int flowinfo = 0;
 310         struct in6_addr in6_addr_any = IN6ADDR_ANY_INIT;
 311
 312         if (!tb)
 313                 return;
 314
 315         if (tb[IFLA_GRE_FLAGS])
 316                 flags = rta_getattr_u32(tb[IFLA_GRE_FLAGS]);
 317
 318         if (tb[IFLA_GRE_FLOWINFO])
 319                 flags = rta_getattr_u32(tb[IFLA_GRE_FLOWINFO]);
 320
 321         if (tb[IFLA_GRE_REMOTE]) {
 322                 struct in6_addr addr;
 323
 324                 memcpy(&addr, RTA_DATA(tb[IFLA_GRE_REMOTE]), sizeof(addr));
 325
 326                 if (memcmp(&addr, &in6_addr_any, sizeof(addr)))
 327                         remote = format_host(AF_INET6, sizeof(addr), &addr);
 328         }
 329
 330         fprintf(f, "remote %s ", remote);
 331
 332         if (tb[IFLA_GRE_LOCAL]) {
 333                 struct in6_addr addr;
 334
 335                 memcpy(&addr, RTA_DATA(tb[IFLA_GRE_LOCAL]), sizeof(addr));
 336
 337                 if (memcmp(&addr, &in6_addr_any, sizeof(addr)))
 338                         local = format_host(AF_INET6, sizeof(addr), &addr);
 339         }
 340
 341         fprintf(f, "local %s ", local);
 342
 343         if (tb[IFLA_GRE_LINK] && rta_getattr_u32(tb[IFLA_GRE_LINK])) {
 344                 unsigned int link = rta_getattr_u32(tb[IFLA_GRE_LINK]);
 345                 const char *n = if_indextoname(link, s2);
 346
 347                 if (n)
 348                         fprintf(f, "dev %s ", n);
 349                 else
 350                         fprintf(f, "dev %u ", link);
 351         }
 352
 353         if (tb[IFLA_GRE_TTL] && rta_getattr_u8(tb[IFLA_GRE_TTL]))
 354                 fprintf(f, "hoplimit %d ", rta_getattr_u8(tb[IFLA_GRE_TTL]));
 355
 356         if (flags & IP6_TNL_F_IGN_ENCAP_LIMIT)
 357                 fprintf(f, "encaplimit none ");
 358         else if (tb[IFLA_GRE_ENCAP_LIMIT]) {
 359                 int encap_limit = rta_getattr_u8(tb[IFLA_GRE_ENCAP_LIMIT]);
 360
 361                 fprintf(f, "encaplimit %d ", encap_limit);
 362         }
 363
 364         if (flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 365                 fprintf(f, "flowlabel inherit ");
 366         else
 367                 fprintf(f, "flowlabel 0x%05x ", ntohl(flowinfo & IP6_FLOWINFO_FLOWLABEL));
 368
 369         if (flags & IP6_TNL_F_RCV_DSCP_COPY)
 370                 fprintf(f, "dscp inherit ");
 371
 372         if (tb[IFLA_GRE_IFLAGS])
 373                 iflags = rta_getattr_u16(tb[IFLA_GRE_IFLAGS]);
 374
 375         if (tb[IFLA_GRE_OFLAGS])
 376                 oflags = rta_getattr_u16(tb[IFLA_GRE_OFLAGS]);
 377
 378         if ((iflags & GRE_KEY) && tb[IFLA_GRE_IKEY]) {
 379                 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_IKEY]), s2, sizeof(s2));
 380                 fprintf(f, "ikey %s ", s2);
 381         }
 382
 383         if ((oflags & GRE_KEY) && tb[IFLA_GRE_OKEY]) {
 384                 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_OKEY]), s2, sizeof(s2));
 385                 fprintf(f, "okey %s ", s2);
 386         }
 387
 388         if (iflags & GRE_SEQ)
 389                 fputs("iseq ", f);
 390         if (oflags & GRE_SEQ)
 391                 fputs("oseq ", f);
 392         if (iflags & GRE_CSUM)
 393                 fputs("icsum ", f);
 394         if (oflags & GRE_CSUM)
 395                 fputs("ocsum ", f);
 396 }
 397
 398 static void gre_print_help(struct link_util *lu, int argc, char **argv,
 399         FILE *f)
 400 {
 401         print_usage(f);
 402 }
 403
 404 struct link_util ip6gre_link_util = {
 405         .id = "ip6gre",
 406         .maxattr = IFLA_GRE_MAX,
 407         .parse_opt = gre_parse_opt,
 408         .print_opt = gre_print_opt,
 409         .print_help = gre_print_help,
 410 };
 411
 412 struct link_util ip6gretap_link_util = {
 413         .id = "ip6gretap",
 414         .maxattr = IFLA_GRE_MAX,
 415         .parse_opt = gre_parse_opt,
 416         .print_opt = gre_print_opt,
 417         .print_help = gre_print_help,
 418 };