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                 device_add_user(&state->l3_dev,
 184                         device_get(blobmsg_data(tb[NOTIFY_IFNAME]), true));
 185                 device_claim(&state->l3_dev);
 186                 state->proto.iface->l3_dev = &state->l3_dev;
 187                 state->proto.proto_event(&state->proto, IFPEV_UP);
 188         } else {
 189                 state->proto.proto_event(&state->proto, IFPEV_LINK_LOST);
 190         }
 191
 192         return 0;
 193 }
 194
 195 struct interface_proto_state *
 196 proto_shell_attach(const struct proto_handler *h, struct interface *iface,
 197                    struct blob_attr *attr)
 198 {
 199         struct proto_shell_state *state;
 200
 201         state = calloc(1, sizeof(*state));
 202         state->config = malloc(blob_pad_len(attr));
 203         if (!state->config)
 204                 goto error;
 205
 206         memcpy(state->config, attr, blob_pad_len(attr));
 207         state->proto.free = proto_shell_free;
 208         state->proto.notify = proto_shell_notify;
 209         state->proto.cb = proto_shell_handler;
 210         state->setup_timeout.cb = proto_shell_setup_timeout_cb;
 211         state->setup_task.cb = proto_shell_setup_cb;
 212         state->teardown_task.cb = proto_shell_teardown_cb;
 213         state->handler = container_of(h, struct proto_shell_handler, proto);
 214
 215         return &state->proto;
 216
 217 error:
 218         free(state);
 219         return NULL;
 220 }
 221
 222 static json_object *
 223 check_type(json_object *obj, json_type type)
 224 {
 225         if (!obj)
 226                 return NULL;
 227
 228         if (json_object_get_type(obj) != type)
 229                 return NULL;
 230
 231         return obj;
 232 }
 233
 234 static inline json_object *
 235 get_field(json_object *obj, const char *name, json_type type)
 236 {
 237         return check_type(json_object_object_get(obj, name), type);
 238 }
 239
 240 static char *
 241 proto_shell_parse_config(struct config_param_list *config, json_object *obj)
 242 {
 243         struct blobmsg_policy *attrs;
 244         char *str_buf, *str_cur;
 245         int str_len = 0;
 246         int i;
 247
 248         attrs = calloc(1, sizeof(*attrs));
 249         if (!attrs)
 250                 return NULL;
 251
 252         config->n_params = json_object_array_length(obj);
 253         config->params = attrs;
 254         for (i = 0; i < config->n_params; i++) {
 255                 json_object *cur, *name, *type;
 256
 257                 cur = check_type(json_object_array_get_idx(obj, i), json_type_array);
 258                 if (!cur)
 259                         goto error;
 260
 261                 name = check_type(json_object_array_get_idx(cur, 0), json_type_string);
 262                 if (!name)
 263                         goto error;
 264
 265                 type = check_type(json_object_array_get_idx(cur, 1), json_type_int);
 266                 if (!type)
 267                         goto error;
 268
 269                 attrs[i].name = json_object_get_string(name);
 270                 attrs[i].type = json_object_get_int(type);
 271                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 272                         goto error;
 273
 274                 str_len += strlen(attrs[i].name + 1);
 275         }
 276
 277         str_buf = malloc(str_len);
 278         if (!str_buf)
 279                 goto error;
 280
 281         str_cur = str_buf;
 282         for (i = 0; i < config->n_params; i++) {
 283                 const char *name = attrs[i].name;
 284
 285                 attrs[i].name = str_cur;
 286                 str_cur += sprintf(str_cur, "%s", name) + 1;
 287         }
 288
 289         return str_buf;
 290
 291 error:
 292         free(attrs);
 293         config->n_params = 0;
 294         return NULL;
 295 }
 296
 297 static void
 298 proto_shell_add_handler(const char *script, json_object *obj)
 299 {
 300         struct proto_shell_handler *handler;
 301         struct proto_handler *proto;
 302         json_object *config, *tmp;
 303         const char *name;
 304         char *str;
 305
 306         if (!check_type(obj, json_type_object))
 307                 return;
 308
 309         tmp = get_field(obj, "name", json_type_string);
 310         if (!tmp)
 311                 return;
 312
 313         name = json_object_get_string(tmp);
 314
 315         handler = calloc(1, sizeof(*handler) +
 316                          strlen(script) + 1 +
 317                          strlen(name) + 1);
 318         if (!handler)
 319                 return;
 320
 321         strcpy(handler->script_name, script);
 322
 323         str = handler->script_name + strlen(handler->script_name) + 1;
 324         strcpy(str, name);
 325
 326         proto = &handler->proto;
 327         proto->name = str;
 328         proto->config_params = &handler->config;
 329         proto->attach = proto_shell_attach;
 330
 331         tmp = get_field(obj, "no-device", json_type_boolean);
 332         if (tmp && json_object_get_boolean(tmp))
 333                 handler->proto.flags |= PROTO_FLAG_NODEV;
 334
 335         config = get_field(obj, "config", json_type_array);
 336         if (config)
 337                 handler->config_buf = proto_shell_parse_config(&handler->config, config);
 338
 339         DPRINTF("Add handler for script %s: %s\n", script, proto->name);
 340         add_proto_handler(proto);
 341 }
 342
 343 static void proto_shell_add_script(const char *name)
 344 {
 345         struct json_tokener *tok = NULL;
 346         json_object *obj;
 347         static char buf[512];
 348         char *start, *end, *cmd;
 349         FILE *f;
 350         int buflen, len;
 351
 352 #define DUMP_SUFFIX     " '' dump"
 353
 354         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
 355         sprintf(cmd, "%s" DUMP_SUFFIX, name);
 356
 357         f = popen(cmd, "r");
 358         if (!f)
 359                 return;
 360
 361         do {
 362                 buflen = fread(buf, 1, sizeof(buf) - 1, f);
 363                 if (buflen <= 0)
 364                         continue;
 365
 366                 start = buf;
 367                 len = buflen;
 368                 do {
 369                         end = memchr(start, '\n', len);
 370                         if (end)
 371                                 len = end - start;
 372
 373                         if (!tok)
 374                                 tok = json_tokener_new();
 375
 376                         obj = json_tokener_parse_ex(tok, start, len);
 377                         if (!is_error(obj)) {
 378                                 proto_shell_add_handler(name, obj);
 379                                 json_object_put(obj);
 380                                 json_tokener_free(tok);
 381                                 tok = NULL;
 382                         }
 383
 384                         if (end) {
 385                                 start = end + 1;
 386                                 len = buflen - (start - buf);
 387                         }
 388                 } while (len > 0);
 389         } while (!feof(f) && !ferror(f));
 390
 391         if (tok)
 392                 json_tokener_free(tok);
 393
 394         pclose(f);
 395 }
 396
 397 void __init proto_shell_init(void)
 398 {
 399         glob_t g;
 400         int main_fd;
 401         int i;
 402
 403         main_fd = open(".", O_RDONLY | O_DIRECTORY);
 404         if (main_fd < 0)
 405                 return;
 406
 407         if (chdir(main_path)) {
 408                 perror("chdir(main path)");
 409                 goto close_cur;
 410         }
 411
 412         if (chdir("./proto"))
 413                 goto close_cur;
 414
 415         proto_fd = open(".", O_RDONLY | O_DIRECTORY);
 416         if (proto_fd < 0)
 417                 goto close_cur;
 418
 419         glob("./*.sh", 0, NULL, &g);
 420         for (i = 0; i < g.gl_pathc; i++)
 421                 proto_shell_add_script(g.gl_pathv[i]);
 422
 423 close_cur:
 424         fchdir(main_fd);
 425         close(main_fd);
 426 }