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