handler.c

   1 /*
   2  * netifd - network interface daemon
   3  * Copyright (C) 2012-2013 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #define _GNU_SOURCE
  16 #include <glob.h>
  17 #include <fcntl.h>
  18 #include <stdio.h>
  19 #include <unistd.h>
  20
  21 #include "netifd.h"
  22 #include "system.h"
  23 #include "handler.h"
  24
  25 static int
  26 netifd_dir_push(int fd)
  27 {
  28         int prev_fd = open(".", O_RDONLY | O_DIRECTORY);
  29         system_fd_set_cloexec(prev_fd);
  30         if (fd >= 0)
  31                 fchdir(fd);
  32         return prev_fd;
  33 }
  34
  35 static void
  36 netifd_dir_pop(int prev_fd)
  37 {
  38         fchdir(prev_fd);
  39         close(prev_fd);
  40 }
  41
  42 int netifd_open_subdir(const char *name)
  43 {
  44         int prev_dir;
  45         int ret = -1;
  46
  47         prev_dir = netifd_dir_push(-1);
  48         if (chdir(main_path)) {
  49                 perror("chdir(main path)");
  50                 goto out;
  51         }
  52
  53         ret = open(name, O_RDONLY | O_DIRECTORY);
  54         if (ret >= 0)
  55                 system_fd_set_cloexec(ret);
  56
  57 out:
  58         netifd_dir_pop(prev_dir);
  59         return ret;
  60 }
  61
  62 static void
  63 netifd_init_script_handler(const char *script, json_object *obj, script_dump_cb cb)
  64 {
  65         json_object *tmp;
  66         const char *name;
  67
  68         if (!json_check_type(obj, json_type_object))
  69                 return;
  70
  71         tmp = json_get_field(obj, "name", json_type_string);
  72         if (!tmp)
  73                 return;
  74
  75         name = json_object_get_string(tmp);
  76         cb(script, name, obj);
  77 }
  78
  79 static void
  80 netifd_parse_script_handler(const char *name, script_dump_cb cb)
  81 {
  82         struct json_tokener *tok = NULL;
  83         json_object *obj;
  84         static char buf[512];
  85         char *start, *cmd;
  86         FILE *f;
  87         int len;
  88
  89 #define DUMP_SUFFIX     " '' dump"
  90
  91         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
  92         sprintf(cmd, "%s" DUMP_SUFFIX, name);
  93
  94         f = popen(cmd, "r");
  95         if (!f)
  96                 return;
  97
  98         do {
  99                 start = fgets(buf, sizeof(buf), f);
 100                 if (!start)
 101                         continue;
 102
 103                 len = strlen(start);
 104
 105                 if (!tok)
 106                         tok = json_tokener_new();
 107
 108                 obj = json_tokener_parse_ex(tok, start, len);
 109                 if (!is_error(obj)) {
 110                         netifd_init_script_handler(name, obj, cb);
 111                         json_object_put(obj);
 112                         json_tokener_free(tok);
 113                         tok = NULL;
 114                 } else if (start[len - 1] == '\n') {
 115                         json_tokener_free(tok);
 116                         tok = NULL;
 117                 }
 118         } while (!feof(f) && !ferror(f));
 119
 120         if (tok)
 121                 json_tokener_free(tok);
 122
 123         pclose(f);
 124 }
 125
 126 void netifd_init_script_handlers(int dir_fd, script_dump_cb cb)
 127 {
 128         glob_t g;
 129         int i, prev_fd;
 130
 131         prev_fd = netifd_dir_push(dir_fd);
 132         glob("./*.sh", 0, NULL, &g);
 133         for (i = 0; i < g.gl_pathc; i++)
 134                 netifd_parse_script_handler(g.gl_pathv[i], cb);
 135         netifd_dir_pop(prev_fd);
 136 }
 137
 138 char *
 139 netifd_handler_parse_config(struct uci_blob_param_list *config, json_object *obj)
 140 {
 141         struct blobmsg_policy *attrs;
 142         char *str_buf, *str_cur;
 143         int str_len = 0;
 144         int i;
 145
 146         config->n_params = json_object_array_length(obj);
 147         attrs = calloc(1, sizeof(*attrs) * config->n_params);
 148         if (!attrs)
 149                 return NULL;
 150
 151         config->params = attrs;
 152         for (i = 0; i < config->n_params; i++) {
 153                 json_object *cur, *name, *type;
 154
 155                 cur = json_check_type(json_object_array_get_idx(obj, i), json_type_array);
 156                 if (!cur)
 157                         goto error;
 158
 159                 name = json_check_type(json_object_array_get_idx(cur, 0), json_type_string);
 160                 if (!name)
 161                         goto error;
 162
 163                 type = json_check_type(json_object_array_get_idx(cur, 1), json_type_int);
 164                 if (!type)
 165                         goto error;
 166
 167                 attrs[i].name = json_object_get_string(name);
 168                 attrs[i].type = json_object_get_int(type);
 169                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 170                         goto error;
 171
 172                 str_len += strlen(attrs[i].name) + 1;
 173         }
 174
 175         str_buf = malloc(str_len);
 176         if (!str_buf)
 177                 goto error;
 178
 179         str_cur = str_buf;
 180         for (i = 0; i < config->n_params; i++) {
 181                 const char *name = attrs[i].name;
 182
 183                 attrs[i].name = str_cur;
 184                 str_cur += sprintf(str_cur, "%s", name) + 1;
 185         }
 186
 187         return str_buf;
 188
 189 error:
 190         free(attrs);
 191         config->n_params = 0;
 192         return NULL;
 193 }