interface.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2021 Felix Fietkau <nbd@nbd.name>
   4  */
   5 #include <sys/types.h>
   6 #include <sys/socket.h>
   7 #include <sys/ioctl.h>
   8 #include <net/if_arp.h>
   9 #include <net/if.h>
  10
  11 #include <unistd.h>
  12 #include <errno.h>
  13
  14 #include <libubox/vlist.h>
  15 #include <libubox/avl-cmp.h>
  16 #include <libubox/uloop.h>
  17
  18 #include "qosify.h"
  19
  20 static void interface_update_cb(struct vlist_tree *tree,
  21                                 struct vlist_node *node_new,
  22                                 struct vlist_node *node_old);
  23
  24 static VLIST_TREE(devices, avl_strcmp, interface_update_cb, true, false);
  25 static VLIST_TREE(interfaces, avl_strcmp, interface_update_cb, true, false);
  26 static int socket_fd;
  27
  28 #define APPEND(_buf, _ofs, _format, ...) _ofs += snprintf(_buf + _ofs, sizeof(_buf) - _ofs, _format, ##__VA_ARGS__)
  29
  30 struct qosify_iface_config {
  31         struct blob_attr *data;
  32
  33         bool ingress;
  34         bool egress;
  35         bool nat;
  36         bool host_isolate;
  37         bool autorate_ingress;
  38
  39         const char *bandwidth_up;
  40         const char *bandwidth_down;
  41         const char *mode;
  42         const char *common_opts;
  43         const char *ingress_opts;
  44         const char *egress_opts;
  45 };
  46
  47
  48 struct qosify_iface {
  49         struct vlist_node node;
  50
  51         char ifname[IFNAMSIZ];
  52         bool active;
  53
  54         bool device;
  55         struct blob_attr *config_data;
  56         struct qosify_iface_config config;
  57 };
  58
  59 enum {
  60         IFACE_ATTR_BW_UP,
  61         IFACE_ATTR_BW_DOWN,
  62         IFACE_ATTR_INGRESS,
  63         IFACE_ATTR_EGRESS,
  64         IFACE_ATTR_MODE,
  65         IFACE_ATTR_NAT,
  66         IFACE_ATTR_HOST_ISOLATE,
  67         IFACE_ATTR_AUTORATE_IN,
  68         IFACE_ATTR_INGRESS_OPTS,
  69         IFACE_ATTR_EGRESS_OPTS,
  70         IFACE_ATTR_OPTS,
  71         __IFACE_ATTR_MAX
  72 };
  73
  74 static inline const char *qosify_iface_name(struct qosify_iface *iface)
  75 {
  76         return iface->node.avl.key;
  77 }
  78
  79 static void
  80 iface_config_parse(struct blob_attr *attr, struct blob_attr **tb)
  81 {
  82         static const struct blobmsg_policy policy[__IFACE_ATTR_MAX] = {
  83                 [IFACE_ATTR_BW_UP] = { "bandwidth_up", BLOBMSG_TYPE_STRING },
  84                 [IFACE_ATTR_BW_DOWN] = { "bandwidth_down", BLOBMSG_TYPE_STRING },
  85                 [IFACE_ATTR_INGRESS] = { "ingress", BLOBMSG_TYPE_BOOL },
  86                 [IFACE_ATTR_EGRESS] = { "egress", BLOBMSG_TYPE_BOOL },
  87                 [IFACE_ATTR_MODE] = { "mode", BLOBMSG_TYPE_STRING },
  88                 [IFACE_ATTR_NAT] = { "nat", BLOBMSG_TYPE_BOOL },
  89                 [IFACE_ATTR_HOST_ISOLATE] = { "host_isolate", BLOBMSG_TYPE_BOOL },
  90                 [IFACE_ATTR_AUTORATE_IN] = { "autorate_ingress", BLOBMSG_TYPE_BOOL },
  91                 [IFACE_ATTR_INGRESS_OPTS] = { "ingress_options", BLOBMSG_TYPE_STRING },
  92                 [IFACE_ATTR_EGRESS_OPTS] = { "egress_options", BLOBMSG_TYPE_STRING },
  93                 [IFACE_ATTR_OPTS] = { "options", BLOBMSG_TYPE_STRING },
  94         };
  95
  96         blobmsg_parse(policy, __IFACE_ATTR_MAX, tb, blobmsg_data(attr), blobmsg_len(attr));
  97 }
  98
  99 static bool
 100 iface_config_equal(struct qosify_iface *if1, struct qosify_iface *if2)
 101 {
 102         struct blob_attr *tb1[__IFACE_ATTR_MAX], *tb2[__IFACE_ATTR_MAX];
 103         int i;
 104
 105         iface_config_parse(if1->config_data, tb1);
 106         iface_config_parse(if2->config_data, tb2);
 107
 108         for (i = 0; i < __IFACE_ATTR_MAX; i++) {
 109                 if (!!tb1[i] != !!tb2[i])
 110                         return false;
 111
 112                 if (!tb1[i])
 113                         continue;
 114
 115                 if (blob_raw_len(tb1[i]) != blob_raw_len(tb2[i]))
 116                         return false;
 117
 118                 if (memcmp(tb1[i], tb2[i], blob_raw_len(tb1[i])) != 0)
 119                         return false;
 120         }
 121
 122         return true;
 123 }
 124
 125 static const char *check_str(struct blob_attr *attr)
 126 {
 127         const char *str = blobmsg_get_string(attr);
 128
 129         if (strchr(str, '\''))
 130                 return NULL;
 131
 132         return str;
 133 }
 134
 135 static void
 136 iface_config_set(struct qosify_iface *iface, struct blob_attr *attr)
 137 {
 138         struct qosify_iface_config *cfg = &iface->config;
 139         struct blob_attr *tb[__IFACE_ATTR_MAX];
 140         struct blob_attr *cur;
 141
 142         iface_config_parse(attr, tb);
 143
 144         memset(cfg, 0, sizeof(*cfg));
 145
 146         /* defaults */
 147         cfg->mode = "diffserv4";
 148         cfg->ingress = true;
 149         cfg->egress = true;
 150         cfg->host_isolate = true;
 151         cfg->autorate_ingress = false;
 152         cfg->nat = !iface->device;
 153
 154         if ((cur = tb[IFACE_ATTR_BW_UP]) != NULL)
 155                 cfg->bandwidth_up = check_str(cur);
 156         if ((cur = tb[IFACE_ATTR_BW_DOWN]) != NULL)
 157                 cfg->bandwidth_down = check_str(cur);
 158         if ((cur = tb[IFACE_ATTR_MODE]) != NULL)
 159                 cfg->mode = check_str(cur);
 160         if ((cur = tb[IFACE_ATTR_OPTS]) != NULL)
 161                 cfg->common_opts = check_str(cur);
 162         if ((cur = tb[IFACE_ATTR_EGRESS_OPTS]) != NULL)
 163                 cfg->egress_opts = check_str(cur);
 164         if ((cur = tb[IFACE_ATTR_INGRESS_OPTS]) != NULL)
 165                 cfg->ingress_opts = check_str(cur);
 166         if ((cur = tb[IFACE_ATTR_INGRESS]) != NULL)
 167                 cfg->ingress = blobmsg_get_bool(cur);
 168         if ((cur = tb[IFACE_ATTR_EGRESS]) != NULL)
 169                 cfg->egress = blobmsg_get_bool(cur);
 170         if ((cur = tb[IFACE_ATTR_NAT]) != NULL)
 171                 cfg->nat = blobmsg_get_bool(cur);
 172         if ((cur = tb[IFACE_ATTR_HOST_ISOLATE]) != NULL)
 173                 cfg->host_isolate = blobmsg_get_bool(cur);
 174         if ((cur = tb[IFACE_ATTR_AUTORATE_IN]) != NULL)
 175                 cfg->autorate_ingress = blobmsg_get_bool(cur);
 176 }
 177
 178 static const char *
 179 interface_ifb_name(struct qosify_iface *iface)
 180 {
 181         static char ifname[IFNAMSIZ + 1] = "ifb-";
 182         int len = strlen(iface->ifname);
 183
 184         if (len + 4 < IFNAMSIZ) {
 185                 snprintf(ifname + 4, IFNAMSIZ - 4, "%s", iface->ifname);
 186
 187                 return ifname;
 188         }
 189
 190         ifname[4] = iface->ifname[0];
 191         ifname[5] = iface->ifname[1];
 192         snprintf(ifname + 6, IFNAMSIZ - 6, "%s", iface->ifname + len - (IFNAMSIZ + 6) - 1);
 193
 194         return ifname;
 195 }
 196
 197 static int
 198 prepare_tc_cmd(char *buf, int len, const char *type, const char *cmd,
 199                const char *dev, const char *extra)
 200 {
 201         return snprintf(buf, len, "tc %s %s dev '%s' %s", type, cmd, dev, extra);
 202 }
 203
 204 static int
 205 __cmd_add_del_qdisc(const char *ifname, const char *type, bool add)
 206 {
 207         char buf[64];
 208
 209         prepare_tc_cmd(buf, sizeof(buf), "qdisc", add ? "add" : "del", ifname, type);
 210
 211         return qosify_run_cmd(buf, true);
 212 }
 213
 214 static int
 215 cmd_del_qdisc(const char *ifname, const char *type)
 216 {
 217         return __cmd_add_del_qdisc(ifname, type, false);
 218 }
 219
 220
 221 static int
 222 cmd_add_qdisc(struct qosify_iface *iface, const char *ifname, bool egress, bool eth)
 223 {
 224         struct qosify_iface_config *cfg = &iface->config;
 225         const char *bw = egress ? cfg->bandwidth_up : cfg->bandwidth_down;
 226         const char *dir_opts = egress ? cfg->egress_opts : cfg->ingress_opts;
 227         char buf[512];
 228         int ofs;
 229
 230         __cmd_add_del_qdisc(ifname, "clsact", true);
 231
 232         ofs = prepare_tc_cmd(buf, sizeof(buf), "qdisc", "add", ifname, "root cake");
 233         if (bw)
 234                 APPEND(buf, ofs, " bandwidth %s", bw);
 235
 236         APPEND(buf, ofs, " %s %sgress", cfg->mode, egress ? "e" : "in");
 237         if (!egress && cfg->autorate_ingress)
 238                 APPEND(buf, ofs, " autorate-ingress");
 239
 240         if (cfg->host_isolate)
 241                 APPEND(buf, ofs, " %snat dual-%shost",
 242                         cfg->nat ? "" : "no",
 243                         egress ? "src" : "dst");
 244         else
 245                 APPEND(buf, ofs, " flows");
 246
 247         APPEND(buf, ofs, " %s %s",
 248                cfg->common_opts ? cfg->common_opts : "",
 249                dir_opts ? dir_opts : "");
 250
 251         qosify_run_cmd(buf, false);
 252
 253         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", ifname, "egress bpf");
 254         APPEND(buf, ofs, " object-pinned /sys/fs/bpf/qosify_%sgress_%s verbose direct-action",
 255                egress ? "e" : "in",
 256                    eth ? "eth" : "ip");
 257
 258         return qosify_run_cmd(buf, false);
 259 }
 260
 261 static int
 262 cmd_del_ingress(struct qosify_iface *iface)
 263 {
 264         char buf[256];
 265
 266         snprintf(buf, sizeof(buf), "ip link del '%s'", interface_ifb_name(iface));
 267
 268         return qosify_run_cmd(buf, true);
 269 }
 270
 271 static int
 272 cmd_add_ingress(struct qosify_iface *iface, bool eth)
 273 {
 274         const char *ifbdev = interface_ifb_name(iface);
 275         char buf[256];
 276         int ofs;
 277
 278         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 279         APPEND(buf, ofs, " protocol ip prio 5 u32 match ip sport 53 0xffff "
 280                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 281         qosify_run_cmd(buf, false);
 282
 283         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 284         APPEND(buf, ofs, " protocol ip prio 5 u32 match ip sport 53 0xffff "
 285                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 286         qosify_run_cmd(buf, false);
 287
 288         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 289         APPEND(buf, ofs, " protocol 802.1Q prio 6 u32 offset plus 4 match ip sport 53 0xffff "
 290                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 291         qosify_run_cmd(buf, false);
 292
 293         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 294         APPEND(buf, ofs, " protocol ipv6 prio 7 u32 match ip6 sport 53 0xffff "
 295                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 296         qosify_run_cmd(buf, false);
 297
 298         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 299         APPEND(buf, ofs, " protocol ipv6 prio 8 u32 offset plus 4 match ip6 sport 53 0xffff "
 300                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 301         qosify_run_cmd(buf, false);
 302
 303         if (!iface->config.ingress)
 304                 return 0;
 305
 306         snprintf(buf, sizeof(buf), "ip link add '%s' type ifb", ifbdev);
 307         qosify_run_cmd(buf, false);
 308
 309         cmd_add_qdisc(iface, ifbdev, false, eth);
 310
 311         snprintf(buf, sizeof(buf), "ip link set dev '%s' up", ifbdev);
 312         qosify_run_cmd(buf, false);
 313
 314         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " ingress");
 315         APPEND(buf, ofs, " protocol all prio 10 u32 match u32 0 0 "
 316                          "flowid 1:1 action mirred egress redirect dev '%s'", ifbdev);
 317         return qosify_run_cmd(buf, false);
 318 }
 319
 320 static void
 321 interface_clear_qdisc(struct qosify_iface *iface)
 322 {
 323         cmd_del_qdisc(iface->ifname, "root");
 324         cmd_del_qdisc(iface->ifname, "clsact");
 325         cmd_del_ingress(iface);
 326 }
 327
 328 static void
 329 interface_start(struct qosify_iface *iface)
 330 {
 331         struct ifreq ifr = {};
 332         bool eth;
 333
 334         if (!iface->ifname[0] || iface->active)
 335                 return;
 336
 337         ULOG_INFO("start interface %s\n", iface->ifname);
 338
 339         strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
 340         if (ioctl(socket_fd, SIOCGIFHWADDR, &ifr) < 0) {
 341                 ULOG_ERR("ioctl(SIOCGIFHWADDR, %s) failed: %s\n", iface->ifname, strerror(errno));
 342                 return;
 343         }
 344
 345         eth = ifr.ifr_hwaddr.sa_family == ARPHRD_ETHER;
 346
 347         interface_clear_qdisc(iface);
 348         if (iface->config.egress)
 349                 cmd_add_qdisc(iface, iface->ifname, true, eth);
 350         cmd_add_ingress(iface, eth);
 351
 352         iface->active = true;
 353 }
 354
 355 static void
 356 interface_stop(struct qosify_iface *iface)
 357 {
 358         if (!iface->ifname[0] || !iface->active)
 359                 return;
 360
 361         ULOG_INFO("stop interface %s\n", iface->ifname);
 362         iface->active = false;
 363
 364         interface_clear_qdisc(iface);
 365 }
 366
 367 static void
 368 interface_set_config(struct qosify_iface *iface, struct blob_attr *config)
 369 {
 370         iface->config_data = blob_memdup(config);
 371         iface_config_set(iface, iface->config_data);
 372         interface_start(iface);
 373 }
 374
 375 static void
 376 interface_update_cb(struct vlist_tree *tree,
 377                     struct vlist_node *node_new, struct vlist_node *node_old)
 378 {
 379         struct qosify_iface *if_new = NULL, *if_old = NULL;
 380
 381         if (node_new)
 382                 if_new = container_of(node_new, struct qosify_iface, node);
 383         if (node_old)
 384                 if_old = container_of(node_old, struct qosify_iface, node);
 385
 386         if (if_new && if_old) {
 387                 if (!iface_config_equal(if_old, if_new)) {
 388                         interface_stop(if_old);
 389                         free(if_old->config_data);
 390                         interface_set_config(if_old, if_new->config_data);
 391                 }
 392
 393                 free(if_new);
 394                 return;
 395         }
 396
 397         if (if_old) {
 398                 interface_stop(if_old);
 399                 free(if_old->config_data);
 400                 free(if_old);
 401         }
 402
 403         if (if_new)
 404                 interface_set_config(if_new, if_new->config_data);
 405 }
 406
 407 static void
 408 interface_create(struct blob_attr *attr, bool device)
 409 {
 410         struct qosify_iface *iface;
 411         const char *name = blobmsg_name(attr);
 412         int name_len = strlen(name);
 413         char *name_buf;
 414
 415         if (strchr(name, '\''))
 416                 return;
 417
 418         if (name_len >= IFNAMSIZ)
 419                 return;
 420
 421         if (blobmsg_type(attr) != BLOBMSG_TYPE_TABLE)
 422                 return;
 423
 424         iface = calloc_a(sizeof(*iface), &name_buf, name_len + 1);
 425         strcpy(name_buf, blobmsg_name(attr));
 426         iface->config_data = attr;
 427         iface->device = device;
 428         vlist_add(device ? &devices : &interfaces, &iface->node, name_buf);
 429 }
 430
 431 void qosify_iface_config_update(struct blob_attr *ifaces, struct blob_attr *devs)
 432 {
 433         struct blob_attr *cur;
 434         int rem;
 435
 436         vlist_update(&devices);
 437         blobmsg_for_each_attr(cur, devs, rem)
 438                 interface_create(cur, true);
 439         vlist_flush(&devices);
 440
 441         vlist_update(&interfaces);
 442         blobmsg_for_each_attr(cur, ifaces, rem)
 443                 interface_create(cur, false);
 444         vlist_flush(&interfaces);
 445 }
 446
 447 static void
 448 qosify_iface_check_device(struct qosify_iface *iface)
 449 {
 450         const char *name = qosify_iface_name(iface);
 451         int ifindex;
 452
 453         ifindex = if_nametoindex(name);
 454         if (!ifindex) {
 455                 interface_stop(iface);
 456                 iface->ifname[0] = 0;
 457         } else {
 458                 snprintf(iface->ifname, sizeof(iface->ifname), "%s", name);
 459                 interface_start(iface);
 460         }
 461 }
 462
 463 static void
 464 qosify_iface_check_interface(struct qosify_iface *iface)
 465 {
 466         const char *name = qosify_iface_name(iface);
 467         char ifname[IFNAMSIZ];
 468
 469         if (qosify_ubus_check_interface(name, ifname, sizeof(ifname)) == 0) {
 470                 snprintf(iface->ifname, sizeof(iface->ifname), "%s", ifname);
 471                 interface_start(iface);
 472         } else {
 473                 interface_stop(iface);
 474                 iface->ifname[0] = 0;
 475         }
 476 }
 477
 478 static void qos_iface_check_cb(struct uloop_timeout *t)
 479 {
 480         struct qosify_iface *iface;
 481
 482         vlist_for_each_element(&devices, iface, node)
 483                 qosify_iface_check_device(iface);
 484         vlist_for_each_element(&interfaces, iface, node)
 485                 qosify_iface_check_interface(iface);
 486 }
 487
 488 void qosify_iface_check(void)
 489 {
 490         static struct uloop_timeout timer = {
 491                 .cb = qos_iface_check_cb,
 492         };
 493
 494         uloop_timeout_set(&timer, 10);
 495 }
 496
 497 static void
 498 __qosify_iface_status(struct blob_buf *b, struct qosify_iface *iface)
 499 {
 500         void *c;
 501
 502         c = blobmsg_open_table(b, qosify_iface_name(iface));
 503         blobmsg_add_u8(b, "active", iface->active);
 504         if (iface->ifname)
 505                 blobmsg_add_string(b, "ifname", iface->ifname);
 506         blobmsg_add_u8(b, "egress", iface->config.egress);
 507         blobmsg_add_u8(b, "ingress", iface->config.ingress);
 508         blobmsg_close_table(b, c);
 509
 510 }
 511
 512 void qosify_iface_status(struct blob_buf *b)
 513 {
 514         struct qosify_iface *iface;
 515         void *c;
 516
 517         c = blobmsg_open_table(b, "devices");
 518         vlist_for_each_element(&devices, iface, node)
 519                 __qosify_iface_status(b, iface);
 520         blobmsg_close_table(b, c);
 521
 522         c = blobmsg_open_table(b, "interfaces");
 523         vlist_for_each_element(&interfaces, iface, node)
 524                 __qosify_iface_status(b, iface);
 525         blobmsg_close_table(b, c);
 526 }
 527
 528 int qosify_iface_init(void)
 529 {
 530         socket_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
 531         if (socket < 0)
 532                 return -1;
 533
 534         return 0;
 535 }
 536
 537 void qosify_iface_stop(void)
 538 {
 539         struct qosify_iface *iface;
 540
 541         vlist_for_each_element(&interfaces, iface, node)
 542                 interface_stop(iface);
 543         vlist_for_each_element(&devices, iface, node)
 544                 interface_stop(iface);
 545 }
 546