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[5];
  61         char *config;
  62         int ret;
  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[0] = handler->script_name;
  72         argv[1] = handler->proto.name;
  73         argv[2] = "teardown";
  74         argv[3] = config;
  75         argv[4] = NULL;
  76
  77         switch(cmd) {
  78         case PROTO_CMD_SETUP:
  79                 argv[2] = "setup";
  80                 /* fall through */
  81         case PROTO_CMD_TEARDOWN:
  82                 ret = run_script(argv);
  83                 break;
  84         }
  85
  86         free(config);
  87
  88         return ret;
  89 }
  90
  91 static void
  92 proto_shell_free(struct interface_proto_state *proto)
  93 {
  94         struct proto_shell_state *state;
  95
  96         state = container_of(proto, struct proto_shell_state, proto);
  97         free(state->config);
  98         free(state);
  99 }
 100
 101 struct interface_proto_state *
 102 proto_shell_attach(const struct proto_handler *h, struct interface *iface,
 103                    struct blob_attr *attr)
 104 {
 105         struct proto_shell_state *state;
 106
 107         state = calloc(1, sizeof(*state));
 108         state->config = malloc(blob_pad_len(attr));
 109         if (!state->config)
 110                 goto error;
 111
 112         memcpy(state->config, attr, blob_pad_len(attr));
 113         state->proto.free = proto_shell_free;
 114         state->proto.handler = proto_shell_handler;
 115         state->handler = container_of(h, struct proto_shell_handler, proto);
 116
 117         return &state->proto;
 118
 119 error:
 120         free(state);
 121         return NULL;
 122 }
 123
 124 static char *
 125 proto_shell_parse_config(struct config_param_list *config, struct json_object *obj)
 126 {
 127         struct blobmsg_policy *attrs;
 128         char *str_buf, *str_cur;
 129         int str_len = 0;
 130         int i;
 131
 132         attrs = calloc(1, sizeof(*attrs));
 133         if (!attrs)
 134                 return NULL;
 135
 136         config->n_params = json_object_array_length(obj);
 137         config->params = attrs;
 138         for (i = 0; i < config->n_params; i++) {
 139                 struct json_object *cur, *name, *type;
 140
 141                 cur = json_object_array_get_idx(obj, i);
 142                 if (!cur || json_object_get_type(cur) != json_type_array)
 143                         goto error;
 144
 145                 name = json_object_array_get_idx(cur, 0);
 146                 if (!name || json_object_get_type(name) != json_type_string)
 147                         goto error;
 148
 149                 type = json_object_array_get_idx(cur, 1);
 150                 if (!type || json_object_get_type(type) != json_type_int)
 151                         goto error;
 152
 153                 attrs[i].name = json_object_get_string(name);
 154                 attrs[i].type = json_object_get_int(type);
 155                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 156                         goto error;
 157
 158                 str_len += strlen(attrs[i].name + 1);
 159         }
 160
 161         str_buf = malloc(str_len);
 162         if (!str_buf)
 163                 goto error;
 164
 165         str_cur = str_buf;
 166         for (i = 0; i < config->n_params; i++) {
 167                 const char *name = attrs[i].name;
 168
 169                 attrs[i].name = str_cur;
 170                 str_cur += sprintf(str_cur, "%s", name) + 1;
 171         }
 172
 173         return str_buf;
 174
 175 error:
 176         free(attrs);
 177         config->n_params = 0;
 178         return NULL;
 179 }
 180
 181 static void
 182 proto_shell_add_handler(const char *script, struct json_object *obj)
 183 {
 184         struct proto_shell_handler *handler;
 185         struct proto_handler *proto;
 186         json_object *config, *tmp;
 187         const char *name;
 188         char *str;
 189
 190         if (json_object_get_type(obj) != json_type_object)
 191                 return;
 192
 193         tmp = json_object_object_get(obj, "name");
 194         if (!tmp || json_object_get_type(tmp) != json_type_string)
 195                 return;
 196
 197         name = json_object_get_string(tmp);
 198
 199         handler = calloc(1, sizeof(*handler) +
 200                          strlen(script) + 1 +
 201                          strlen(name) + 1);
 202         if (!handler)
 203                 return;
 204
 205         strcpy(handler->script_name, script);
 206
 207         str = handler->script_name + strlen(handler->script_name) + 1;
 208         strcpy(str, name);
 209
 210         proto = &handler->proto;
 211         proto->name = str;
 212         proto->config_params = &handler->config;
 213         proto->attach = proto_shell_attach;
 214
 215         config = json_object_object_get(obj, "config");
 216         if (config && json_object_get_type(config) == json_type_array)
 217                 handler->config_buf = proto_shell_parse_config(&handler->config, config);
 218
 219         DPRINTF("Add handler for script %s: %s\n", script, proto->name);
 220         add_proto_handler(proto);
 221 }
 222
 223 static void proto_shell_add_script(const char *name)
 224 {
 225         struct json_tokener *tok = NULL;
 226         struct json_object *obj;
 227         static char buf[512];
 228         char *start, *end, *cmd;
 229         FILE *f;
 230         int buflen, len;
 231
 232 #define DUMP_SUFFIX     " '' dump"
 233
 234         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
 235         sprintf(cmd, "%s" DUMP_SUFFIX, name);
 236
 237         f = popen(cmd, "r");
 238         if (!f)
 239                 return;
 240
 241         do {
 242                 buflen = fread(buf, 1, sizeof(buf) - 1, f);
 243                 if (buflen <= 0)
 244                         continue;
 245
 246                 start = buf;
 247                 len = buflen;
 248                 do {
 249                         end = memchr(start, '\n', len);
 250                         if (end)
 251                                 len = end - start;
 252
 253                         if (!tok)
 254                                 tok = json_tokener_new();
 255
 256                         obj = json_tokener_parse_ex(tok, start, len);
 257                         if (!is_error(obj)) {
 258                                 proto_shell_add_handler(name, obj);
 259                                 json_object_put(obj);
 260                                 json_tokener_free(tok);
 261                                 tok = NULL;
 262                         }
 263
 264                         if (end) {
 265                                 start = end + 1;
 266                                 len = buflen - (start - buf);
 267                         }
 268                 } while (len > 0);
 269         } while (!feof(f) && !ferror(f));
 270
 271         if (tok)
 272                 json_tokener_free(tok);
 273
 274         pclose(f);
 275 }
 276
 277 void __init proto_shell_init(void)
 278 {
 279         glob_t g;
 280         int main_fd;
 281         int i;
 282
 283         main_fd = open(".", O_RDONLY | O_DIRECTORY);
 284         if (main_fd < 0)
 285                 return;
 286
 287         if (chdir(main_path)) {
 288                 perror("chdir(main path)");
 289                 goto close_cur;
 290         }
 291
 292         if (chdir("./proto"))
 293                 goto close_cur;
 294
 295         proto_fd = open(".", O_RDONLY | O_DIRECTORY);
 296         if (proto_fd < 0)
 297                 goto close_cur;
 298
 299         glob("./*.sh", 0, NULL, &g);
 300         for (i = 0; i < g.gl_pathc; i++)
 301                 proto_shell_add_script(g.gl_pathv[i]);
 302
 303 close_cur:
 304         fchdir(main_fd);
 305         close(main_fd);
 306 }