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