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