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
   8 #include <libubox/blobmsg_json.h>
   9
  10 #include "netifd.h"
  11 #include "interface.h"
  12 #include "interface-ip.h"
  13 #include "proto.h"
  14
  15 static LIST_HEAD(handlers);
  16 static int proto_fd;
  17
  18 struct proto_shell_handler {
  19         struct list_head list;
  20         struct proto_handler proto;
  21         struct config_param_list config;
  22         char *config_buf;
  23         char script_name[];
  24 };
  25
  26 struct proto_shell_state {
  27         struct interface_proto_state proto;
  28         struct proto_shell_handler *handler;
  29         struct blob_attr *config;
  30 };
  31
  32 static int run_script(const char **argv)
  33 {
  34         int pid, ret;
  35
  36         if ((pid = fork()) < 0)
  37                 return -1;
  38
  39         if (!pid) {
  40                 fchdir(proto_fd);
  41                 execvp(argv[0], (char **) argv);
  42                 exit(127);
  43         }
  44
  45         if (waitpid(pid, &ret, 0) == -1)
  46                 ret = -1;
  47
  48         if (ret > 0)
  49                 return -ret;
  50
  51         return 0;
  52 }
  53
  54 static int
  55 proto_shell_handler(struct interface_proto_state *proto,
  56                     enum interface_proto_cmd cmd, bool force)
  57 {
  58         struct proto_shell_state *state;
  59         struct proto_shell_handler *handler;
  60         const char *argv[6];
  61         char *config;
  62         int ret, i = 0;
  63
  64         state = container_of(proto, struct proto_shell_state, proto);
  65         handler = state->handler;
  66
  67         config = blobmsg_format_json(state->config, true);
  68         if (!config)
  69                 return -1;
  70
  71         argv[i++] = handler->script_name;
  72         argv[i++] = handler->proto.name;
  73         argv[i++] = cmd == PROTO_CMD_SETUP ? "setup" : "teardown";
  74         argv[i++] = proto->iface->name;
  75         argv[i++] = config;
  76         if (proto->iface->main_dev.dev)
  77                 argv[i++] = proto->iface->main_dev.dev->ifname;
  78         argv[i] = NULL;
  79
  80         ret = run_script(argv);
  81         free(config);
  82
  83         return ret;
  84 }
  85
  86 static void
  87 proto_shell_free(struct interface_proto_state *proto)
  88 {
  89         struct proto_shell_state *state;
  90
  91         state = container_of(proto, struct proto_shell_state, proto);
  92         free(state->config);
  93         free(state);
  94 }
  95
  96 struct interface_proto_state *
  97 proto_shell_attach(const struct proto_handler *h, struct interface *iface,
  98                    struct blob_attr *attr)
  99 {
 100         struct proto_shell_state *state;
 101
 102         state = calloc(1, sizeof(*state));
 103         state->config = malloc(blob_pad_len(attr));
 104         if (!state->config)
 105                 goto error;
 106
 107         memcpy(state->config, attr, blob_pad_len(attr));
 108         state->proto.free = proto_shell_free;
 109         state->proto.cb = proto_shell_handler;
 110         state->handler = container_of(h, struct proto_shell_handler, proto);
 111
 112         return &state->proto;
 113
 114 error:
 115         free(state);
 116         return NULL;
 117 }
 118
 119 static json_object *
 120 check_type(json_object *obj, json_type type)
 121 {
 122         if (!obj)
 123                 return NULL;
 124
 125         if (json_object_get_type(obj) != type)
 126                 return NULL;
 127
 128         return obj;
 129 }
 130
 131 static inline json_object *
 132 get_field(json_object *obj, const char *name, json_type type)
 133 {
 134         return check_type(json_object_object_get(obj, name), type);
 135 }
 136
 137 static char *
 138 proto_shell_parse_config(struct config_param_list *config, json_object *obj)
 139 {
 140         struct blobmsg_policy *attrs;
 141         char *str_buf, *str_cur;
 142         int str_len = 0;
 143         int i;
 144
 145         attrs = calloc(1, sizeof(*attrs));
 146         if (!attrs)
 147                 return NULL;
 148
 149         config->n_params = json_object_array_length(obj);
 150         config->params = attrs;
 151         for (i = 0; i < config->n_params; i++) {
 152                 json_object *cur, *name, *type;
 153
 154                 cur = check_type(json_object_array_get_idx(obj, i), json_type_array);
 155                 if (!cur)
 156                         goto error;
 157
 158                 name = check_type(json_object_array_get_idx(cur, 0), json_type_string);
 159                 if (!name)
 160                         goto error;
 161
 162                 type = check_type(json_object_array_get_idx(cur, 1), json_type_int);
 163                 if (!type)
 164                         goto error;
 165
 166                 attrs[i].name = json_object_get_string(name);
 167                 attrs[i].type = json_object_get_int(type);
 168                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 169                         goto error;
 170
 171                 str_len += strlen(attrs[i].name + 1);
 172         }
 173
 174         str_buf = malloc(str_len);
 175         if (!str_buf)
 176                 goto error;
 177
 178         str_cur = str_buf;
 179         for (i = 0; i < config->n_params; i++) {
 180                 const char *name = attrs[i].name;
 181
 182                 attrs[i].name = str_cur;
 183                 str_cur += sprintf(str_cur, "%s", name) + 1;
 184         }
 185
 186         return str_buf;
 187
 188 error:
 189         free(attrs);
 190         config->n_params = 0;
 191         return NULL;
 192 }
 193
 194 static void
 195 proto_shell_add_handler(const char *script, json_object *obj)
 196 {
 197         struct proto_shell_handler *handler;
 198         struct proto_handler *proto;
 199         json_object *config, *tmp;
 200         const char *name;
 201         char *str;
 202
 203         if (!check_type(obj, json_type_object))
 204                 return;
 205
 206         tmp = get_field(obj, "name", json_type_string);
 207         if (!tmp)
 208                 return;
 209
 210         name = json_object_get_string(tmp);
 211
 212         handler = calloc(1, sizeof(*handler) +
 213                          strlen(script) + 1 +
 214                          strlen(name) + 1);
 215         if (!handler)
 216                 return;
 217
 218         strcpy(handler->script_name, script);
 219
 220         str = handler->script_name + strlen(handler->script_name) + 1;
 221         strcpy(str, name);
 222
 223         proto = &handler->proto;
 224         proto->name = str;
 225         proto->config_params = &handler->config;
 226         proto->attach = proto_shell_attach;
 227
 228         tmp = get_field(obj, "no-device", json_type_boolean);
 229         if (tmp && json_object_get_boolean(tmp))
 230                 handler->proto.flags |= PROTO_FLAG_NODEV;
 231
 232         config = get_field(obj, "config", json_type_array);
 233         if (config)
 234                 handler->config_buf = proto_shell_parse_config(&handler->config, config);
 235
 236         DPRINTF("Add handler for script %s: %s\n", script, proto->name);
 237         add_proto_handler(proto);
 238 }
 239
 240 static void proto_shell_add_script(const char *name)
 241 {
 242         struct json_tokener *tok = NULL;
 243         json_object *obj;
 244         static char buf[512];
 245         char *start, *end, *cmd;
 246         FILE *f;
 247         int buflen, len;
 248
 249 #define DUMP_SUFFIX     " '' dump"
 250
 251         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
 252         sprintf(cmd, "%s" DUMP_SUFFIX, name);
 253
 254         f = popen(cmd, "r");
 255         if (!f)
 256                 return;
 257
 258         do {
 259                 buflen = fread(buf, 1, sizeof(buf) - 1, f);
 260                 if (buflen <= 0)
 261                         continue;
 262
 263                 start = buf;
 264                 len = buflen;
 265                 do {
 266                         end = memchr(start, '\n', len);
 267                         if (end)
 268                                 len = end - start;
 269
 270                         if (!tok)
 271                                 tok = json_tokener_new();
 272
 273                         obj = json_tokener_parse_ex(tok, start, len);
 274                         if (!is_error(obj)) {
 275                                 proto_shell_add_handler(name, obj);
 276                                 json_object_put(obj);
 277                                 json_tokener_free(tok);
 278                                 tok = NULL;
 279                         }
 280
 281                         if (end) {
 282                                 start = end + 1;
 283                                 len = buflen - (start - buf);
 284                         }
 285                 } while (len > 0);
 286         } while (!feof(f) && !ferror(f));
 287
 288         if (tok)
 289                 json_tokener_free(tok);
 290
 291         pclose(f);
 292 }
 293
 294 void __init proto_shell_init(void)
 295 {
 296         glob_t g;
 297         int main_fd;
 298         int i;
 299
 300         main_fd = open(".", O_RDONLY | O_DIRECTORY);
 301         if (main_fd < 0)
 302                 return;
 303
 304         if (chdir(main_path)) {
 305                 perror("chdir(main path)");
 306                 goto close_cur;
 307         }
 308
 309         if (chdir("./proto"))
 310                 goto close_cur;
 311
 312         proto_fd = open(".", O_RDONLY | O_DIRECTORY);
 313         if (proto_fd < 0)
 314                 goto close_cur;
 315
 316         glob("./*.sh", 0, NULL, &g);
 317         for (i = 0; i < g.gl_pathc; i++)
 318                 proto_shell_add_script(g.gl_pathv[i]);
 319
 320 close_cur:
 321         fchdir(main_fd);
 322         close(main_fd);
 323 }