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 {
  64                 struct nlmsghdr n;
  65                 struct ifinfomsg i;
  66                 char buf[1024];
  67         } req;
  68         struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1);
  69         struct rtattr *tb[IFLA_MAX + 1];
  70         struct rtattr *linkinfo[IFLA_INFO_MAX+1];
  71         struct rtattr *greinfo[IFLA_GRE_MAX + 1];
  72         __u16 iflags = 0;
  73         __u16 oflags = 0;
  74         unsigned ikey = 0;
  75         unsigned okey = 0;
  76         struct in6_addr raddr = IN6ADDR_ANY_INIT;
  77         struct in6_addr laddr = IN6ADDR_ANY_INIT;
  78         unsigned link = 0;
  79         unsigned flowinfo = 0;
  80         unsigned flags = 0;
  81         __u8 hop_limit = DEFAULT_TNL_HOP_LIMIT;
  82         __u8 encap_limit = IPV6_DEFAULT_TNL_ENCAP_LIMIT;
  83         int len;
  84
  85         if (!(n->nlmsg_flags & NLM_F_CREATE)) {
  86                 memset(&req, 0, sizeof(req));
  87
  88                 req.n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi));
  89                 req.n.nlmsg_flags = NLM_F_REQUEST;
  90                 req.n.nlmsg_type = RTM_GETLINK;
  91                 req.i.ifi_family = preferred_family;
  92                 req.i.ifi_index = ifi->ifi_index;
  93
  94                 if (rtnl_talk(&rth, &req.n, &req.n, sizeof(req)) < 0) {
  95 get_failed:
  96                         fprintf(stderr,
  97                                 "Failed to get existing tunnel info.\n");
  98                         return -1;
  99                 }
 100
 101                 len = req.n.nlmsg_len;
 102                 len -= NLMSG_LENGTH(sizeof(*ifi));
 103                 if (len < 0)
 104                         goto get_failed;
 105
 106                 parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len);
 107
 108                 if (!tb[IFLA_LINKINFO])
 109                         goto get_failed;
 110
 111                 parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
 112
 113                 if (!linkinfo[IFLA_INFO_DATA])
 114                         goto get_failed;
 115
 116                 parse_rtattr_nested(greinfo, IFLA_GRE_MAX,
 117                                     linkinfo[IFLA_INFO_DATA]);
 118
 119                 if (greinfo[IFLA_GRE_IKEY])
 120                         ikey = rta_getattr_u32(greinfo[IFLA_GRE_IKEY]);
 121
 122                 if (greinfo[IFLA_GRE_OKEY])
 123                         okey = rta_getattr_u32(greinfo[IFLA_GRE_OKEY]);
 124
 125                 if (greinfo[IFLA_GRE_IFLAGS])
 126                         iflags = rta_getattr_u16(greinfo[IFLA_GRE_IFLAGS]);
 127
 128                 if (greinfo[IFLA_GRE_OFLAGS])
 129                         oflags = rta_getattr_u16(greinfo[IFLA_GRE_OFLAGS]);
 130
 131                 if (greinfo[IFLA_GRE_LOCAL])
 132                         memcpy(&laddr, RTA_DATA(greinfo[IFLA_GRE_LOCAL]), sizeof(laddr));
 133
 134                 if (greinfo[IFLA_GRE_REMOTE])
 135                         memcpy(&raddr, RTA_DATA(greinfo[IFLA_GRE_REMOTE]), sizeof(raddr));
 136
 137                 if (greinfo[IFLA_GRE_TTL])
 138                         hop_limit = rta_getattr_u8(greinfo[IFLA_GRE_TTL]);
 139
 140                 if (greinfo[IFLA_GRE_LINK])
 141                         link = rta_getattr_u32(greinfo[IFLA_GRE_LINK]);
 142
 143                 if (greinfo[IFLA_GRE_ENCAP_LIMIT])
 144                         encap_limit = rta_getattr_u8(greinfo[IFLA_GRE_ENCAP_LIMIT]);
 145
 146                 if (greinfo[IFLA_GRE_FLOWINFO])
 147                         flowinfo = rta_getattr_u32(greinfo[IFLA_GRE_FLOWINFO]);
 148
 149                 if (greinfo[IFLA_GRE_FLAGS])
 150                         flags = rta_getattr_u32(greinfo[IFLA_GRE_FLAGS]);
 151         }
 152
 153         while (argc > 0) {
 154                 if (!matches(*argv, "key")) {
 155                         unsigned uval;
 156
 157                         NEXT_ARG();
 158                         iflags |= GRE_KEY;
 159                         oflags |= GRE_KEY;
 160                         if (strchr(*argv, '.'))
 161                                 uval = get_addr32(*argv);
 162                         else {
 163                                 if (get_unsigned(&uval, *argv, 0) < 0) {
 164                                         fprintf(stderr,
 165                                                 "Invalid value for \"key\"\n");
 166                                         exit(-1);
 167                                 }
 168                                 uval = htonl(uval);
 169                         }
 170
 171                         ikey = okey = uval;
 172                 } else if (!matches(*argv, "ikey")) {
 173                         unsigned uval;
 174
 175                         NEXT_ARG();
 176                         iflags |= GRE_KEY;
 177                         if (strchr(*argv, '.'))
 178                                 uval = get_addr32(*argv);
 179                         else {
 180                                 if (get_unsigned(&uval, *argv, 0)<0) {
 181                                         fprintf(stderr, "invalid value of \"ikey\"\n");
 182                                         exit(-1);
 183                                 }
 184                                 uval = htonl(uval);
 185                         }
 186                         ikey = uval;
 187                 } else if (!matches(*argv, "okey")) {
 188                         unsigned uval;
 189
 190                         NEXT_ARG();
 191                         oflags |= GRE_KEY;
 192                         if (strchr(*argv, '.'))
 193                                 uval = get_addr32(*argv);
 194                         else {
 195                                 if (get_unsigned(&uval, *argv, 0)<0) {
 196                                         fprintf(stderr, "invalid value of \"okey\"\n");
 197                                         exit(-1);
 198                                 }
 199                                 uval = htonl(uval);
 200                         }
 201                         okey = uval;
 202                 } else if (!matches(*argv, "seq")) {
 203                         iflags |= GRE_SEQ;
 204                         oflags |= GRE_SEQ;
 205                 } else if (!matches(*argv, "iseq")) {
 206                         iflags |= GRE_SEQ;
 207                 } else if (!matches(*argv, "oseq")) {
 208                         oflags |= GRE_SEQ;
 209                 } else if (!matches(*argv, "csum")) {
 210                         iflags |= GRE_CSUM;
 211                         oflags |= GRE_CSUM;
 212                 } else if (!matches(*argv, "icsum")) {
 213                         iflags |= GRE_CSUM;
 214                 } else if (!matches(*argv, "ocsum")) {
 215                         oflags |= GRE_CSUM;
 216                 } else if (!matches(*argv, "remote")) {
 217                         inet_prefix addr;
 218                         NEXT_ARG();
 219                         get_prefix(&addr, *argv, preferred_family);
 220                         if (addr.family == AF_UNSPEC)
 221                                 invarg("\"remote\" address family is AF_UNSPEC", *argv);
 222                         memcpy(&raddr, &addr.data, sizeof(raddr));
 223                 } else if (!matches(*argv, "local")) {
 224                         inet_prefix addr;
 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                         NEXT_ARG();
 242                         if (get_u8(&uval, *argv, 0))
 243                                 invarg("invalid TTL", *argv);
 244                         hop_limit = uval;
 245                 } else if (!matches(*argv, "tos") ||
 246                            !matches(*argv, "tclass") ||
 247                            !matches(*argv, "dsfield")) {
 248                         __u8 uval;
 249                         NEXT_ARG();
 250                         if (strcmp(*argv, "inherit") == 0)
 251                                 flags |= IP6_TNL_F_USE_ORIG_TCLASS;
 252                         else {
 253                                 if (get_u8(&uval, *argv, 16))
 254                                         invarg("invalid TClass", *argv);
 255                                 flowinfo |= htonl((__u32)uval << 20) & IP6_FLOWINFO_TCLASS;
 256                                 flags &= ~IP6_TNL_F_USE_ORIG_TCLASS;
 257                         }
 258                 } else if (strcmp(*argv, "flowlabel") == 0 ||
 259                            strcmp(*argv, "fl") == 0) {
 260                         __u32 uval;
 261                         NEXT_ARG();
 262                         if (strcmp(*argv, "inherit") == 0)
 263                                 flags |= IP6_TNL_F_USE_ORIG_FLOWLABEL;
 264                         else {
 265                                 if (get_u32(&uval, *argv, 16))
 266                                         invarg("invalid Flowlabel", *argv);
 267                                 if (uval > 0xFFFFF)
 268                                         invarg("invalid Flowlabel", *argv);
 269                                 flowinfo |= htonl(uval) & IP6_FLOWINFO_FLOWLABEL;
 270                                 flags &= ~IP6_TNL_F_USE_ORIG_FLOWLABEL;
 271                         }
 272                 } else if (strcmp(*argv, "dscp") == 0) {
 273                         NEXT_ARG();
 274                         if (strcmp(*argv, "inherit") != 0)
 275                                 invarg("not inherit", *argv);
 276                         flags |= IP6_TNL_F_RCV_DSCP_COPY;
 277                 } else
 278                         usage();
 279                 argc--; argv++;
 280         }
 281
 282         addattr32(n, 1024, IFLA_GRE_IKEY, ikey);
 283         addattr32(n, 1024, IFLA_GRE_OKEY, okey);
 284         addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2);
 285         addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2);
 286         addattr_l(n, 1024, IFLA_GRE_LOCAL, &laddr, sizeof(laddr));
 287         addattr_l(n, 1024, IFLA_GRE_REMOTE, &raddr, sizeof(raddr));
 288         if (link)
 289                 addattr32(n, 1024, IFLA_GRE_LINK, link);
 290         addattr_l(n, 1024, IFLA_GRE_TTL, &hop_limit, 1);
 291         addattr_l(n, 1024, IFLA_GRE_ENCAP_LIMIT, &encap_limit, 1);
 292         addattr_l(n, 1024, IFLA_GRE_FLOWINFO, &flowinfo, 4);
 293         addattr_l(n, 1024, IFLA_GRE_FLAGS, &flowinfo, 4);
 294
 295         return 0;
 296 }
 297
 298 static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 299 {
 300         char s1[1024];
 301         char s2[64];
 302         const char *local = "any";
 303         const char *remote = "any";
 304         unsigned iflags = 0;
 305         unsigned oflags = 0;
 306         unsigned flags = 0;
 307         unsigned flowinfo = 0;
 308         struct in6_addr in6_addr_any = IN6ADDR_ANY_INIT;
 309
 310         if (!tb)
 311                 return;
 312
 313         if (tb[IFLA_GRE_FLAGS])
 314                 flags = rta_getattr_u32(tb[IFLA_GRE_FLAGS]);
 315
 316         if (tb[IFLA_GRE_FLOWINFO])
 317                 flags = rta_getattr_u32(tb[IFLA_GRE_FLOWINFO]);
 318
 319         if (tb[IFLA_GRE_REMOTE]) {
 320                 struct in6_addr addr;
 321                 memcpy(&addr, RTA_DATA(tb[IFLA_GRE_REMOTE]), sizeof(addr));
 322
 323                 if (memcmp(&addr, &in6_addr_any, sizeof(addr)))
 324                         remote = format_host(AF_INET6, sizeof(addr), &addr, s1, sizeof(s1));
 325         }
 326
 327         fprintf(f, "remote %s ", remote);
 328
 329         if (tb[IFLA_GRE_LOCAL]) {
 330                 struct in6_addr addr;
 331                 memcpy(&addr, RTA_DATA(tb[IFLA_GRE_LOCAL]), sizeof(addr));
 332
 333                 if (memcmp(&addr, &in6_addr_any, sizeof(addr)))
 334                         local = format_host(AF_INET6, sizeof(addr), &addr, s1, sizeof(s1));
 335         }
 336
 337         fprintf(f, "local %s ", local);
 338
 339         if (tb[IFLA_GRE_LINK] && rta_getattr_u32(tb[IFLA_GRE_LINK])) {
 340                 unsigned link = rta_getattr_u32(tb[IFLA_GRE_LINK]);
 341                 const char *n = if_indextoname(link, s2);
 342
 343                 if (n)
 344                         fprintf(f, "dev %s ", n);
 345                 else
 346                         fprintf(f, "dev %u ", link);
 347         }
 348
 349         if (tb[IFLA_GRE_TTL] && rta_getattr_u8(tb[IFLA_GRE_TTL]))
 350                 fprintf(f, "hoplimit %d ", rta_getattr_u8(tb[IFLA_GRE_TTL]));
 351
 352         if (flags & IP6_TNL_F_IGN_ENCAP_LIMIT)
 353                 fprintf(f, "encaplimit none ");
 354         else if (tb[IFLA_GRE_ENCAP_LIMIT]) {
 355                 int encap_limit = rta_getattr_u8(tb[IFLA_GRE_ENCAP_LIMIT]);
 356
 357                 fprintf(f, "encaplimit %d ", encap_limit);
 358         }
 359
 360         if (flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
 361                 fprintf(f, "flowlabel inherit ");
 362         else
 363                 fprintf(f, "flowlabel 0x%05x ", ntohl(flowinfo & IP6_FLOWINFO_FLOWLABEL));
 364
 365         if (flags & IP6_TNL_F_RCV_DSCP_COPY)
 366                 fprintf(f, "dscp inherit ");
 367
 368         if (tb[IFLA_GRE_IFLAGS])
 369                 iflags = rta_getattr_u16(tb[IFLA_GRE_IFLAGS]);
 370
 371         if (tb[IFLA_GRE_OFLAGS])
 372                 oflags = rta_getattr_u16(tb[IFLA_GRE_OFLAGS]);
 373
 374         if ((iflags & GRE_KEY) && tb[IFLA_GRE_IKEY]) {
 375                 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_IKEY]), s2, sizeof(s2));
 376                 fprintf(f, "ikey %s ", s2);
 377         }
 378
 379         if ((oflags & GRE_KEY) && tb[IFLA_GRE_OKEY]) {
 380                 inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_OKEY]), s2, sizeof(s2));
 381                 fprintf(f, "okey %s ", s2);
 382         }
 383
 384         if (iflags & GRE_SEQ)
 385                 fputs("iseq ", f);
 386         if (oflags & GRE_SEQ)
 387                 fputs("oseq ", f);
 388         if (iflags & GRE_CSUM)
 389                 fputs("icsum ", f);
 390         if (oflags & GRE_CSUM)
 391                 fputs("ocsum ", f);
 392 }
 393
 394 static void gre_print_help(struct link_util *lu, int argc, char **argv,
 395         FILE *f)
 396 {
 397         print_usage(f);
 398 }
 399
 400 struct link_util ip6gre_link_util = {
 401         .id = "ip6gre",
 402         .maxattr = IFLA_GRE_MAX,
 403         .parse_opt = gre_parse_opt,
 404         .print_opt = gre_print_opt,
 405         .print_help = gre_print_help,
 406 };
 407
 408 struct link_util ip6gretap_link_util = {
 409         .id = "ip6gretap",
 410         .maxattr = IFLA_GRE_MAX,
 411         .parse_opt = gre_parse_opt,
 412         .print_opt = gre_print_opt,
 413         .print_help = gre_print_help,
 414 };