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_del_qdisc(const char *ifname, const char *type)
 206 {
 207         char buf[64];
 208
 209         prepare_tc_cmd(buf, sizeof(buf), "qdisc", "del", ifname, type);
 210
 211         return qosify_run_cmd(buf, true);
 212 }
 213
 214 static int
 215 cmd_add_qdisc(struct qosify_iface *iface, const char *ifname, bool egress, bool eth)
 216 {
 217         struct qosify_iface_config *cfg = &iface->config;
 218         const char *bw = egress ? cfg->bandwidth_up : cfg->bandwidth_down;
 219         const char *dir_opts = egress ? cfg->egress_opts : cfg->ingress_opts;
 220         char buf[512];
 221         int ofs;
 222
 223         cmd_del_qdisc(ifname, "root");
 224
 225         ofs = prepare_tc_cmd(buf, sizeof(buf), "qdisc", "add", ifname, "root handle 1: cake");
 226         if (bw)
 227                 APPEND(buf, ofs, " bandwidth %s", bw);
 228
 229         APPEND(buf, ofs, " %s %sgress", cfg->mode, egress ? "e" : "in");
 230         if (!egress && cfg->autorate_ingress)
 231                 APPEND(buf, ofs, " autorate-ingress");
 232
 233         if (cfg->host_isolate)
 234                 APPEND(buf, ofs, " %snat dual-%shost",
 235                         cfg->nat ? "" : "no",
 236                         egress ? "src" : "dst");
 237         else
 238                 APPEND(buf, ofs, " flows");
 239
 240         APPEND(buf, ofs, " %s %s",
 241                cfg->common_opts ? cfg->common_opts : "",
 242                dir_opts ? dir_opts : "");
 243
 244         qosify_run_cmd(buf, false);
 245
 246         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", ifname, "parent 1: bpf");
 247         APPEND(buf, ofs, " object-pinned /sys/fs/bpf/qosify_%sgress_%s verbose direct-action",
 248                egress ? "e" : "in",
 249                    eth ? "eth" : "ip");
 250
 251         return qosify_run_cmd(buf, false);
 252 }
 253
 254 static int
 255 cmd_del_ingress(struct qosify_iface *iface)
 256 {
 257         char buf[256];
 258
 259         cmd_del_qdisc(iface->ifname, "handle ffff: ingress");
 260         snprintf(buf, sizeof(buf), "ip link del '%s'", interface_ifb_name(iface));
 261
 262         return qosify_run_cmd(buf, true);
 263 }
 264
 265
 266 static int
 267 cmd_add_ingress(struct qosify_iface *iface, bool eth)
 268 {
 269         const char *ifbdev = interface_ifb_name(iface);
 270         char buf[256];
 271         int ofs;
 272
 273         cmd_del_ingress(iface);
 274
 275         ofs = prepare_tc_cmd(buf, sizeof(buf), "qdisc", "add", iface->ifname, " handle ffff: ingress");
 276         qosify_run_cmd(buf, false);
 277
 278         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " parent ffff:");
 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, " parent ffff:");
 284         APPEND(buf, ofs, " protocol ipv6 prio 6 u32 match ip6 sport 53 0xffff "
 285                          "flowid 1:1 action mirred egress redirect dev ifb-dns");
 286         qosify_run_cmd(buf, false);
 287
 288         if (!iface->config.ingress)
 289                 return 0;
 290
 291         snprintf(buf, sizeof(buf), "ip link add '%s' type ifb", ifbdev);
 292         qosify_run_cmd(buf, false);
 293
 294         cmd_add_qdisc(iface, ifbdev, false, eth);
 295
 296         snprintf(buf, sizeof(buf), "ip link set dev '%s' up", ifbdev);
 297         qosify_run_cmd(buf, false);
 298
 299         ofs = prepare_tc_cmd(buf, sizeof(buf), "filter", "add", iface->ifname, " parent ffff:");
 300         APPEND(buf, ofs, " protocol all prio 10 u32 match u32 0 0 "
 301                          "flowid 1:1 action mirred egress redirect dev '%s'", ifbdev);
 302         return qosify_run_cmd(buf, false);
 303 }
 304
 305 static void
 306 interface_start(struct qosify_iface *iface)
 307 {
 308         struct ifreq ifr = {};
 309         bool eth;
 310
 311         if (!iface->ifname[0] || iface->active)
 312                 return;
 313
 314         ULOG_INFO("start interface %s\n", iface->ifname);
 315
 316         strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
 317         if (ioctl(socket_fd, SIOCGIFHWADDR, &ifr) < 0) {
 318                 ULOG_ERR("ioctl(SIOCGIFHWADDR, %s) failed: %s\n", iface->ifname, strerror(errno));
 319                 return;
 320         }
 321
 322         eth = ifr.ifr_hwaddr.sa_family == ARPHRD_ETHER;
 323
 324         if (iface->config.egress)
 325                 cmd_add_qdisc(iface, iface->ifname, true, eth);
 326         cmd_add_ingress(iface, eth);
 327
 328         iface->active = true;
 329 }
 330
 331 static void
 332 interface_stop(struct qosify_iface *iface)
 333 {
 334         if (!iface->ifname[0] || !iface->active)
 335                 return;
 336
 337         ULOG_INFO("stop interface %s\n", iface->ifname);
 338         iface->active = false;
 339
 340         if (iface->config.egress)
 341                 cmd_del_qdisc(iface->ifname, "root");
 342         if (iface->config.ingress)
 343                 cmd_del_ingress(iface);
 344 }
 345
 346 static void
 347 interface_set_config(struct qosify_iface *iface, struct blob_attr *config)
 348 {
 349         iface->config_data = blob_memdup(config);
 350         iface_config_set(iface, iface->config_data);
 351         interface_start(iface);
 352 }
 353
 354 static void
 355 interface_update_cb(struct vlist_tree *tree,
 356                     struct vlist_node *node_new, struct vlist_node *node_old)
 357 {
 358         struct qosify_iface *if_new = NULL, *if_old = NULL;
 359
 360         if (node_new)
 361                 if_new = container_of(node_new, struct qosify_iface, node);
 362         if (node_old)
 363                 if_old = container_of(node_old, struct qosify_iface, node);
 364
 365         if (if_new && if_old) {
 366                 if (!iface_config_equal(if_old, if_new)) {
 367                         interface_stop(if_old);
 368                         free(if_old->config_data);
 369                         interface_set_config(if_old, if_new->config_data);
 370                 }
 371
 372                 free(if_new);
 373                 return;
 374         }
 375
 376         if (if_old) {
 377                 interface_stop(if_old);
 378                 free(if_old->config_data);
 379                 free(if_old);
 380         }
 381
 382         if (if_new)
 383                 interface_set_config(if_new, if_new->config_data);
 384 }
 385
 386 static void
 387 interface_create(struct blob_attr *attr, bool device)
 388 {
 389         struct qosify_iface *iface;
 390         const char *name = blobmsg_name(attr);
 391         int name_len = strlen(name);
 392         char *name_buf;
 393
 394         if (strchr(name, '\''))
 395                 return;
 396
 397         if (name_len >= IFNAMSIZ)
 398                 return;
 399
 400         if (blobmsg_type(attr) != BLOBMSG_TYPE_TABLE)
 401                 return;
 402
 403         iface = calloc_a(sizeof(*iface), &name_buf, name_len + 1);
 404         strcpy(name_buf, blobmsg_name(attr));
 405         iface->config_data = attr;
 406         iface->device = device;
 407         vlist_add(device ? &devices : &interfaces, &iface->node, name_buf);
 408 }
 409
 410 void qosify_iface_config_update(struct blob_attr *ifaces, struct blob_attr *devs)
 411 {
 412         struct blob_attr *cur;
 413         int rem;
 414
 415         vlist_update(&devices);
 416         blobmsg_for_each_attr(cur, devs, rem)
 417                 interface_create(cur, true);
 418         vlist_flush(&devices);
 419
 420         vlist_update(&interfaces);
 421         blobmsg_for_each_attr(cur, ifaces, rem)
 422                 interface_create(cur, false);
 423         vlist_flush(&interfaces);
 424 }
 425
 426 static void
 427 qosify_iface_check_device(struct qosify_iface *iface)
 428 {
 429         const char *name = qosify_iface_name(iface);
 430         int ifindex;
 431
 432         ifindex = if_nametoindex(name);
 433         if (!ifindex) {
 434                 interface_stop(iface);
 435                 iface->ifname[0] = 0;
 436         } else {
 437                 snprintf(iface->ifname, sizeof(iface->ifname), "%s", name);
 438                 interface_start(iface);
 439         }
 440 }
 441
 442 static void
 443 qosify_iface_check_interface(struct qosify_iface *iface)
 444 {
 445         const char *name = qosify_iface_name(iface);
 446         char ifname[IFNAMSIZ];
 447
 448         if (qosify_ubus_check_interface(name, ifname, sizeof(ifname)) == 0) {
 449                 snprintf(iface->ifname, sizeof(iface->ifname), "%s", ifname);
 450                 interface_start(iface);
 451         } else {
 452                 interface_stop(iface);
 453                 iface->ifname[0] = 0;
 454         }
 455 }
 456
 457 static void qos_iface_check_cb(struct uloop_timeout *t)
 458 {
 459         struct qosify_iface *iface;
 460
 461         vlist_for_each_element(&devices, iface, node)
 462                 qosify_iface_check_device(iface);
 463         vlist_for_each_element(&interfaces, iface, node)
 464                 qosify_iface_check_interface(iface);
 465 }
 466
 467 void qosify_iface_check(void)
 468 {
 469         static struct uloop_timeout timer = {
 470                 .cb = qos_iface_check_cb,
 471         };
 472
 473         uloop_timeout_set(&timer, 10);
 474 }
 475
 476 static void
 477 __qosify_iface_status(struct blob_buf *b, struct qosify_iface *iface)
 478 {
 479         void *c;
 480
 481         c = blobmsg_open_table(b, qosify_iface_name(iface));
 482         blobmsg_add_u8(b, "active", iface->active);
 483         if (iface->ifname)
 484                 blobmsg_add_string(b, "ifname", iface->ifname);
 485         blobmsg_add_u8(b, "egress", iface->config.egress);
 486         blobmsg_add_u8(b, "ingress", iface->config.ingress);
 487         blobmsg_close_table(b, c);
 488
 489 }
 490
 491 void qosify_iface_status(struct blob_buf *b)
 492 {
 493         struct qosify_iface *iface;
 494         void *c;
 495
 496         c = blobmsg_open_table(b, "devices");
 497         vlist_for_each_element(&devices, iface, node)
 498                 __qosify_iface_status(b, iface);
 499         blobmsg_close_table(b, c);
 500
 501         c = blobmsg_open_table(b, "interfaces");
 502         vlist_for_each_element(&interfaces, iface, node)
 503                 __qosify_iface_status(b, iface);
 504         blobmsg_close_table(b, c);
 505 }
 506
 507 int qosify_iface_init(void)
 508 {
 509         socket_fd = socket(AF_UNIX, SOCK_DGRAM, 0);
 510         if (socket < 0)
 511                 return -1;
 512
 513         return 0;
 514 }
 515
 516 void qosify_iface_stop(void)
 517 {
 518         struct qosify_iface *iface;
 519
 520         vlist_for_each_element(&interfaces, iface, node)
 521                 interface_stop(iface);
 522         vlist_for_each_element(&devices, iface, node)
 523                 interface_stop(iface);
 524 }
 525