proto-shell.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <glob.h>
   5 #include <unistd.h>
   6 #include <fcntl.h>
   7 #include <signal.h>
   8
   9 #include <libubox/blobmsg_json.h>
  10
  11 #include "netifd.h"
  12 #include "interface.h"
  13 #include "interface-ip.h"
  14 #include "proto.h"
  15
  16 static LIST_HEAD(handlers);
  17 static int proto_fd;
  18
  19 struct proto_shell_handler {
  20         struct list_head list;
  21         struct proto_handler proto;
  22         struct config_param_list config;
  23         char *config_buf;
  24         char script_name[];
  25 };
  26
  27 struct proto_shell_state {
  28         struct interface_proto_state proto;
  29         struct proto_shell_handler *handler;
  30         struct blob_attr *config;
  31
  32         struct device_user l3_dev;
  33
  34         struct uloop_timeout setup_timeout;
  35         struct uloop_process setup_task;
  36         struct uloop_process teardown_task;
  37         bool teardown_pending;
  38 };
  39
  40 static int
  41 run_script(const char **argv, struct uloop_process *proc)
  42 {
  43         int pid;
  44
  45         if ((pid = fork()) < 0)
  46                 return -1;
  47
  48         if (!pid) {
  49                 fchdir(proto_fd);
  50                 execvp(argv[0], (char **) argv);
  51                 exit(127);
  52         }
  53
  54         if (pid < 0)
  55                 return -1;
  56
  57         proc->pid = pid;
  58         uloop_process_add(proc);
  59
  60         return 0;
  61 }
  62
  63 static void
  64 proto_shell_set_down(struct proto_shell_state *state)
  65 {
  66         if (!state->l3_dev.dev)
  67                 return;
  68
  69         device_remove_user(&state->l3_dev);
  70 }
  71
  72 static int
  73 proto_shell_handler(struct interface_proto_state *proto,
  74                     enum interface_proto_cmd cmd, bool force)
  75 {
  76         struct proto_shell_state *state;
  77         struct proto_shell_handler *handler;
  78         struct uloop_process *proc;
  79         const char *argv[6];
  80         const char *action;
  81         char *config;
  82         int ret, i = 0;
  83
  84         state = container_of(proto, struct proto_shell_state, proto);
  85         handler = state->handler;
  86
  87         if (cmd == PROTO_CMD_SETUP) {
  88                 action = "setup";
  89                 proc = &state->setup_task;
  90         } else {
  91                 action = "teardown";
  92                 proc = &state->teardown_task;
  93                 if (state->setup_task.pending) {
  94                         uloop_timeout_set(&state->setup_timeout, 1000);
  95                         kill(state->setup_task.pid, SIGINT);
  96                         state->teardown_pending = true;
  97                         return 0;
  98                 }
  99         }
 100
 101         config = blobmsg_format_json(state->config, true);
 102         if (!config)
 103                 return -1;
 104
 105         argv[i++] = handler->script_name;
 106         argv[i++] = handler->proto.name;
 107         argv[i++] = action;
 108         argv[i++] = proto->iface->name;
 109         argv[i++] = config;
 110         if (proto->iface->main_dev.dev)
 111                 argv[i++] = proto->iface->main_dev.dev->ifname;
 112         argv[i] = NULL;
 113
 114         ret = run_script(argv, proc);
 115         free(config);
 116
 117         return ret;
 118 }
 119
 120 static void
 121 proto_shell_setup_timeout_cb(struct uloop_timeout *timeout)
 122 {
 123         struct proto_shell_state *state;
 124
 125         state = container_of(timeout, struct proto_shell_state, setup_timeout);
 126         kill(state->setup_task.pid, SIGKILL);
 127 }
 128
 129 static void
 130 proto_shell_setup_cb(struct uloop_process *p, int ret)
 131 {
 132         struct proto_shell_state *state;
 133
 134         state = container_of(p, struct proto_shell_state, setup_task);
 135         uloop_timeout_cancel(&state->setup_timeout);
 136         if (state->teardown_pending) {
 137                 state->teardown_pending = 0;
 138                 proto_shell_handler(&state->proto, PROTO_CMD_TEARDOWN, false);
 139         }
 140 }
 141
 142 static void
 143 proto_shell_teardown_cb(struct uloop_process *p, int ret)
 144 {
 145         struct proto_shell_state *state;
 146
 147         state = container_of(p, struct proto_shell_state, teardown_task);
 148         proto_shell_set_down(state);
 149         state->proto.proto_event(&state->proto, IFPEV_DOWN);
 150 }
 151
 152 static void
 153 proto_shell_free(struct interface_proto_state *proto)
 154 {
 155         struct proto_shell_state *state;
 156
 157         state = container_of(proto, struct proto_shell_state, proto);
 158         free(state->config);
 159         free(state);
 160 }
 161
 162 enum {
 163         NOTIFY_LINK_UP,
 164         NOTIFY_IFNAME,
 165         __NOTIFY_LAST
 166 };
 167
 168 static const struct blobmsg_policy notify_attr[__NOTIFY_LAST] = {
 169         [NOTIFY_LINK_UP] = { .name = "link-up", .type = BLOBMSG_TYPE_BOOL },
 170         [NOTIFY_IFNAME] = { .name = "ifname", .type = BLOBMSG_TYPE_STRING },
 171 };
 172
 173 static int
 174 proto_shell_notify(struct interface_proto_state *proto, struct blob_attr *attr)
 175 {
 176         struct proto_shell_state *state;
 177         struct blob_attr *tb[__NOTIFY_LAST];
 178         bool up;
 179
 180         state = container_of(proto, struct proto_shell_state, proto);
 181
 182         blobmsg_parse(notify_attr, __NOTIFY_LAST, tb, blob_data(attr), blob_len(attr));
 183         if (!tb[NOTIFY_LINK_UP])
 184                 return UBUS_STATUS_INVALID_ARGUMENT;
 185
 186         up = blobmsg_get_bool(tb[NOTIFY_LINK_UP]);
 187         if (up) {
 188                 if (!tb[NOTIFY_IFNAME])
 189                         return UBUS_STATUS_INVALID_ARGUMENT;
 190
 191                 device_add_user(&state->l3_dev,
 192                         device_get(blobmsg_data(tb[NOTIFY_IFNAME]), true));
 193                 device_claim(&state->l3_dev);
 194                 state->proto.iface->l3_dev = &state->l3_dev;
 195                 state->proto.proto_event(&state->proto, IFPEV_UP);
 196         } else {
 197                 proto_shell_set_down(state);
 198         }
 199
 200         return 0;
 201 }
 202
 203 struct interface_proto_state *
 204 proto_shell_attach(const struct proto_handler *h, struct interface *iface,
 205                    struct blob_attr *attr)
 206 {
 207         struct proto_shell_state *state;
 208
 209         state = calloc(1, sizeof(*state));
 210         state->config = malloc(blob_pad_len(attr));
 211         if (!state->config)
 212                 goto error;
 213
 214         memcpy(state->config, attr, blob_pad_len(attr));
 215         state->proto.free = proto_shell_free;
 216         state->proto.notify = proto_shell_notify;
 217         state->proto.cb = proto_shell_handler;
 218         state->setup_timeout.cb = proto_shell_setup_timeout_cb;
 219         state->setup_task.cb = proto_shell_setup_cb;
 220         state->teardown_task.cb = proto_shell_teardown_cb;
 221         state->handler = container_of(h, struct proto_shell_handler, proto);
 222
 223         return &state->proto;
 224
 225 error:
 226         free(state);
 227         return NULL;
 228 }
 229
 230 static json_object *
 231 check_type(json_object *obj, json_type type)
 232 {
 233         if (!obj)
 234                 return NULL;
 235
 236         if (json_object_get_type(obj) != type)
 237                 return NULL;
 238
 239         return obj;
 240 }
 241
 242 static inline json_object *
 243 get_field(json_object *obj, const char *name, json_type type)
 244 {
 245         return check_type(json_object_object_get(obj, name), type);
 246 }
 247
 248 static char *
 249 proto_shell_parse_config(struct config_param_list *config, json_object *obj)
 250 {
 251         struct blobmsg_policy *attrs;
 252         char *str_buf, *str_cur;
 253         int str_len = 0;
 254         int i;
 255
 256         attrs = calloc(1, sizeof(*attrs));
 257         if (!attrs)
 258                 return NULL;
 259
 260         config->n_params = json_object_array_length(obj);
 261         config->params = attrs;
 262         for (i = 0; i < config->n_params; i++) {
 263                 json_object *cur, *name, *type;
 264
 265                 cur = check_type(json_object_array_get_idx(obj, i), json_type_array);
 266                 if (!cur)
 267                         goto error;
 268
 269                 name = check_type(json_object_array_get_idx(cur, 0), json_type_string);
 270                 if (!name)
 271                         goto error;
 272
 273                 type = check_type(json_object_array_get_idx(cur, 1), json_type_int);
 274                 if (!type)
 275                         goto error;
 276
 277                 attrs[i].name = json_object_get_string(name);
 278                 attrs[i].type = json_object_get_int(type);
 279                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 280                         goto error;
 281
 282                 str_len += strlen(attrs[i].name + 1);
 283         }
 284
 285         str_buf = malloc(str_len);
 286         if (!str_buf)
 287                 goto error;
 288
 289         str_cur = str_buf;
 290         for (i = 0; i < config->n_params; i++) {
 291                 const char *name = attrs[i].name;
 292
 293                 attrs[i].name = str_cur;
 294                 str_cur += sprintf(str_cur, "%s", name) + 1;
 295         }
 296
 297         return str_buf;
 298
 299 error:
 300         free(attrs);
 301         config->n_params = 0;
 302         return NULL;
 303 }
 304
 305 static void
 306 proto_shell_add_handler(const char *script, json_object *obj)
 307 {
 308         struct proto_shell_handler *handler;
 309         struct proto_handler *proto;
 310         json_object *config, *tmp;
 311         const char *name;
 312         char *str;
 313
 314         if (!check_type(obj, json_type_object))
 315                 return;
 316
 317         tmp = get_field(obj, "name", json_type_string);
 318         if (!tmp)
 319                 return;
 320
 321         name = json_object_get_string(tmp);
 322
 323         handler = calloc(1, sizeof(*handler) +
 324                          strlen(script) + 1 +
 325                          strlen(name) + 1);
 326         if (!handler)
 327                 return;
 328
 329         strcpy(handler->script_name, script);
 330
 331         str = handler->script_name + strlen(handler->script_name) + 1;
 332         strcpy(str, name);
 333
 334         proto = &handler->proto;
 335         proto->name = str;
 336         proto->config_params = &handler->config;
 337         proto->attach = proto_shell_attach;
 338
 339         tmp = get_field(obj, "no-device", json_type_boolean);
 340         if (tmp && json_object_get_boolean(tmp))
 341                 handler->proto.flags |= PROTO_FLAG_NODEV;
 342
 343         config = get_field(obj, "config", json_type_array);
 344         if (config)
 345                 handler->config_buf = proto_shell_parse_config(&handler->config, config);
 346
 347         DPRINTF("Add handler for script %s: %s\n", script, proto->name);
 348         add_proto_handler(proto);
 349 }
 350
 351 static void proto_shell_add_script(const char *name)
 352 {
 353         struct json_tokener *tok = NULL;
 354         json_object *obj;
 355         static char buf[512];
 356         char *start, *end, *cmd;
 357         FILE *f;
 358         int buflen, len;
 359
 360 #define DUMP_SUFFIX     " '' dump"
 361
 362         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
 363         sprintf(cmd, "%s" DUMP_SUFFIX, name);
 364
 365         f = popen(cmd, "r");
 366         if (!f)
 367                 return;
 368
 369         do {
 370                 buflen = fread(buf, 1, sizeof(buf) - 1, f);
 371                 if (buflen <= 0)
 372                         continue;
 373
 374                 start = buf;
 375                 len = buflen;
 376                 do {
 377                         end = memchr(start, '\n', len);
 378                         if (end)
 379                                 len = end - start;
 380
 381                         if (!tok)
 382                                 tok = json_tokener_new();
 383
 384                         obj = json_tokener_parse_ex(tok, start, len);
 385                         if (!is_error(obj)) {
 386                                 proto_shell_add_handler(name, obj);
 387                                 json_object_put(obj);
 388                                 json_tokener_free(tok);
 389                                 tok = NULL;
 390                         }
 391
 392                         if (end) {
 393                                 start = end + 1;
 394                                 len = buflen - (start - buf);
 395                         }
 396                 } while (len > 0);
 397         } while (!feof(f) && !ferror(f));
 398
 399         if (tok)
 400                 json_tokener_free(tok);
 401
 402         pclose(f);
 403 }
 404
 405 void __init proto_shell_init(void)
 406 {
 407         glob_t g;
 408         int main_fd;
 409         int i;
 410
 411         main_fd = open(".", O_RDONLY | O_DIRECTORY);
 412         if (main_fd < 0)
 413                 return;
 414
 415         if (chdir(main_path)) {
 416                 perror("chdir(main path)");
 417                 goto close_cur;
 418         }
 419
 420         if (chdir("./proto"))
 421                 goto close_cur;
 422
 423         proto_fd = open(".", O_RDONLY | O_DIRECTORY);
 424         if (proto_fd < 0)
 425                 goto close_cur;
 426
 427         glob("./*.sh", 0, NULL, &g);
 428         for (i = 0; i < g.gl_pathc; i++)
 429                 proto_shell_add_script(g.gl_pathv[i]);
 430
 431 close_cur:
 432         fchdir(main_fd);
 433         close(main_fd);
 434 }