src/libsystemd/sd-network/sd-network.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2011 Lennart Poettering
   7   Copyright 2014 Tom Gundersen
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <sys/inotify.h>
  26 #include <poll.h>
  27
  28 #include "util.h"
  29 #include "macro.h"
  30 #include "strv.h"
  31 #include "fileio.h"
  32 #include "sd-network.h"
  33
  34 _public_ int sd_network_get_operational_state(char **state) {
  35         _cleanup_free_ char *s = NULL;
  36         int r;
  37
  38         assert_return(state, -EINVAL);
  39
  40         r = parse_env_file("/run/systemd/netif/state", NEWLINE, "OPER_STATE", &s, NULL);
  41         if (r == -ENOENT)
  42                 return -ENODATA;
  43         if (r < 0)
  44                 return r;
  45         if (isempty(s))
  46                 return -ENODATA;
  47
  48         *state = s;
  49         s = NULL;
  50
  51         return 0;
  52 }
  53
  54 static int network_get_strv(const char *key, char ***ret) {
  55         _cleanup_strv_free_ char **a = NULL;
  56         _cleanup_free_ char *s = NULL;
  57         int r;
  58
  59         assert_return(ret, -EINVAL);
  60
  61         r = parse_env_file("/run/systemd/netif/state", NEWLINE, key, &s, NULL);
  62         if (r == -ENOENT)
  63                 return -ENODATA;
  64         if (r < 0)
  65                 return r;
  66         if (isempty(s)) {
  67                 *ret = NULL;
  68                 return 0;
  69         }
  70
  71         a = strv_split(s, " ");
  72         if (!a)
  73                 return -ENOMEM;
  74
  75         strv_uniq(a);
  76         r = strv_length(a);
  77
  78         *ret = a;
  79         a = NULL;
  80
  81         return r;
  82 }
  83
  84 _public_ int sd_network_get_dns(char ***ret) {
  85         return network_get_strv("DNS", ret);
  86 }
  87
  88 _public_ int sd_network_get_ntp(char ***ret) {
  89         return network_get_strv("NTP", ret);
  90 }
  91
  92 _public_ int sd_network_get_domains(char ***ret) {
  93         return network_get_strv("DOMAINS", ret);
  94 }
  95
  96 _public_ int sd_network_link_get_setup_state(int ifindex, char **state) {
  97         _cleanup_free_ char *s = NULL, *p = NULL;
  98         int r;
  99
 100         assert_return(ifindex > 0, -EINVAL);
 101         assert_return(state, -EINVAL);
 102
 103         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 104                 return -ENOMEM;
 105
 106         r = parse_env_file(p, NEWLINE, "ADMIN_STATE", &s, NULL);
 107         if (r == -ENOENT)
 108                 return -ENODATA;
 109         if (r < 0)
 110                 return r;
 111         if (isempty(s))
 112                 return -ENODATA;
 113
 114         *state = s;
 115         s = NULL;
 116
 117         return 0;
 118 }
 119
 120 _public_ int sd_network_link_get_network_file(int ifindex, char **filename) {
 121         _cleanup_free_ char *s = NULL, *p = NULL;
 122         int r;
 123
 124         assert_return(ifindex > 0, -EINVAL);
 125         assert_return(filename, -EINVAL);
 126
 127         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 128                 return -ENOMEM;
 129
 130         r = parse_env_file(p, NEWLINE, "NETWORK_FILE", &s, NULL);
 131         if (r == -ENOENT)
 132                 return -ENODATA;
 133         if (r < 0)
 134                 return r;
 135         if (isempty(s))
 136                 return -ENODATA;
 137
 138         *filename = s;
 139         s = NULL;
 140
 141         return 0;
 142 }
 143
 144 _public_ int sd_network_link_get_operational_state(int ifindex, char **state) {
 145         _cleanup_free_ char *s = NULL, *p = NULL;
 146         int r;
 147
 148         assert_return(ifindex > 0, -EINVAL);
 149         assert_return(state, -EINVAL);
 150
 151         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 152                 return -ENOMEM;
 153
 154         r = parse_env_file(p, NEWLINE, "OPER_STATE", &s, NULL);
 155         if (r == -ENOENT)
 156                 return -ENODATA;
 157         if (r < 0)
 158                 return r;
 159         if (isempty(s))
 160                 return -ENODATA;
 161
 162         *state = s;
 163         s = NULL;
 164
 165         return 0;
 166 }
 167
 168 _public_ int sd_network_link_get_llmnr(int ifindex, char **llmnr) {
 169         _cleanup_free_ char *s = NULL, *p = NULL;
 170         int r;
 171
 172         assert_return(ifindex > 0, -EINVAL);
 173         assert_return(llmnr, -EINVAL);
 174
 175         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 176                 return -ENOMEM;
 177
 178         r = parse_env_file(p, NEWLINE, "LLMNR", &s, NULL);
 179         if (r == -ENOENT)
 180                 return -ENODATA;
 181         if (r < 0)
 182                 return r;
 183         if (isempty(s))
 184                 return -ENODATA;
 185
 186         *llmnr = s;
 187         s = NULL;
 188
 189         return 0;
 190 }
 191
 192 _public_ int sd_network_link_get_lldp(int ifindex, char **lldp) {
 193         _cleanup_free_ char *s = NULL, *p = NULL;
 194         size_t size;
 195         int r;
 196
 197         assert_return(ifindex > 0, -EINVAL);
 198         assert_return(lldp, -EINVAL);
 199
 200         if (asprintf(&p, "/run/systemd/netif/lldp/%d", ifindex) < 0)
 201                 return -ENOMEM;
 202
 203         r = read_full_file(p, &s, &size);
 204         if (r == -ENOENT)
 205                 return -ENODATA;
 206         if (r < 0)
 207                 return r;
 208         if (size <= 0)
 209                 return -ENODATA;
 210
 211         *lldp = s;
 212         s = NULL;
 213
 214         return 0;
 215 }
 216
 217
 218 static int network_get_link_strv(const char *key, int ifindex, char ***ret) {
 219         _cleanup_free_ char *p = NULL, *s = NULL;
 220         _cleanup_strv_free_ char **a = NULL;
 221         int r;
 222
 223         assert_return(ifindex > 0, -EINVAL);
 224         assert_return(ret, -EINVAL);
 225
 226         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 227                 return -ENOMEM;
 228
 229         r = parse_env_file(p, NEWLINE, key, &s, NULL);
 230         if (r == -ENOENT)
 231                 return -ENODATA;
 232         if (r < 0)
 233                 return r;
 234         if (isempty(s)) {
 235                 *ret = NULL;
 236                 return 0;
 237         }
 238
 239         a = strv_split(s, " ");
 240         if (!a)
 241                 return -ENOMEM;
 242
 243         strv_uniq(a);
 244         r = strv_length(a);
 245
 246         *ret = a;
 247         a = NULL;
 248
 249         return r;
 250 }
 251
 252 _public_ int sd_network_link_get_dns(int ifindex, char ***ret) {
 253         return network_get_link_strv("DNS", ifindex, ret);
 254 }
 255
 256 _public_ int sd_network_link_get_ntp(int ifindex, char ***ret) {
 257         return network_get_link_strv("NTP", ifindex, ret);
 258 }
 259
 260 _public_ int sd_network_link_get_domains(int ifindex, char ***ret) {
 261         return network_get_link_strv("DOMAINS", ifindex, ret);
 262 }
 263
 264 _public_ int sd_network_link_get_carrier_bound_to(int ifindex, char ***ret) {
 265         return network_get_link_strv("CARRIER_BOUND_TO", ifindex, ret);
 266 }
 267
 268 _public_ int sd_network_link_get_carrier_bound_by(int ifindex, char ***ret) {
 269         return network_get_link_strv("CARRIER_BOUND_BY", ifindex, ret);
 270 }
 271
 272 _public_ int sd_network_link_get_wildcard_domain(int ifindex) {
 273         int r;
 274         _cleanup_free_ char *p = NULL, *s = NULL;
 275
 276         assert_return(ifindex > 0, -EINVAL);
 277
 278         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
 279                 return -ENOMEM;
 280
 281         r = parse_env_file(p, NEWLINE, "WILDCARD_DOMAIN", &s, NULL);
 282         if (r == -ENOENT)
 283                 return -ENODATA;
 284         if (r < 0)
 285                 return r;
 286         if (isempty(s))
 287                 return -ENODATA;
 288
 289         return parse_boolean(s);
 290 }
 291
 292 static inline int MONITOR_TO_FD(sd_network_monitor *m) {
 293         return (int) (unsigned long) m - 1;
 294 }
 295
 296 static inline sd_network_monitor* FD_TO_MONITOR(int fd) {
 297         return (sd_network_monitor*) (unsigned long) (fd + 1);
 298 }
 299
 300 static int monitor_add_inotify_watch(int fd) {
 301         int k;
 302
 303         k = inotify_add_watch(fd, "/run/systemd/netif/links/", IN_MOVED_TO|IN_DELETE);
 304         if (k >= 0)
 305                 return 0;
 306         else if (errno != ENOENT)
 307                 return -errno;
 308
 309         k = inotify_add_watch(fd, "/run/systemd/netif/", IN_CREATE|IN_ISDIR);
 310         if (k >= 0)
 311                 return 0;
 312         else if (errno != ENOENT)
 313                 return -errno;
 314
 315         k = inotify_add_watch(fd, "/run/systemd/", IN_CREATE|IN_ISDIR);
 316         if (k < 0)
 317                 return -errno;
 318
 319         return 0;
 320 }
 321
 322 _public_ int sd_network_monitor_new(sd_network_monitor **m, const char *category) {
 323         _cleanup_close_ int fd = -1;
 324         int k;
 325         bool good = false;
 326
 327         assert_return(m, -EINVAL);
 328
 329         fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
 330         if (fd < 0)
 331                 return -errno;
 332
 333         if (!category || streq(category, "links")) {
 334                 k = monitor_add_inotify_watch(fd);
 335                 if (k < 0)
 336                         return k;
 337
 338                 good = true;
 339         }
 340
 341         if (!good)
 342                 return -EINVAL;
 343
 344         *m = FD_TO_MONITOR(fd);
 345         fd = -1;
 346
 347         return 0;
 348 }
 349
 350 _public_ sd_network_monitor* sd_network_monitor_unref(sd_network_monitor *m) {
 351         int fd;
 352
 353         if (m) {
 354                 fd = MONITOR_TO_FD(m);
 355                 close_nointr(fd);
 356         }
 357
 358         return NULL;
 359 }
 360
 361 _public_ int sd_network_monitor_flush(sd_network_monitor *m) {
 362         union inotify_event_buffer buffer;
 363         struct inotify_event *e;
 364         ssize_t l;
 365         int fd, k;
 366
 367         assert_return(m, -EINVAL);
 368
 369         fd = MONITOR_TO_FD(m);
 370
 371         l = read(fd, &buffer, sizeof(buffer));
 372         if (l < 0) {
 373                 if (errno == EAGAIN || errno == EINTR)
 374                         return 0;
 375
 376                 return -errno;
 377         }
 378
 379         FOREACH_INOTIFY_EVENT(e, buffer, l) {
 380                 if (e->mask & IN_ISDIR) {
 381                         k = monitor_add_inotify_watch(fd);
 382                         if (k < 0)
 383                                 return k;
 384
 385                         k = inotify_rm_watch(fd, e->wd);
 386                         if (k < 0)
 387                                 return -errno;
 388                 }
 389         }
 390
 391         return 0;
 392 }
 393
 394 _public_ int sd_network_monitor_get_fd(sd_network_monitor *m) {
 395
 396         assert_return(m, -EINVAL);
 397
 398         return MONITOR_TO_FD(m);
 399 }
 400
 401 _public_ int sd_network_monitor_get_events(sd_network_monitor *m) {
 402
 403         assert_return(m, -EINVAL);
 404
 405         /* For now we will only return POLLIN here, since we don't
 406          * need anything else ever for inotify.  However, let's have
 407          * this API to keep our options open should we later on need
 408          * it. */
 409         return POLLIN;
 410 }
 411
 412 _public_ int sd_network_monitor_get_timeout(sd_network_monitor *m, uint64_t *timeout_usec) {
 413
 414         assert_return(m, -EINVAL);
 415         assert_return(timeout_usec, -EINVAL);
 416
 417         /* For now we will only return (uint64_t) -1, since we don't
 418          * need any timeout. However, let's have this API to keep our
 419          * options open should we later on need it. */
 420         *timeout_usec = (uint64_t) -1;
 421         return 0;
 422 }