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
  20 #include "netifd.h"
  21 #include "system.h"
  22 #include "handler.h"
  23
  24 static int
  25 netifd_dir_push(int fd)
  26 {
  27         int prev_fd = open(".", O_RDONLY | O_DIRECTORY);
  28         system_fd_set_cloexec(prev_fd);
  29         if (fd >= 0)
  30                 if (fchdir(fd)) {}
  31         return prev_fd;
  32 }
  33
  34 static void
  35 netifd_dir_pop(int prev_fd)
  36 {
  37         if (fchdir(prev_fd)) {}
  38         close(prev_fd);
  39 }
  40
  41 int netifd_open_subdir(const char *name)
  42 {
  43         int prev_dir;
  44         int ret = -1;
  45
  46         prev_dir = netifd_dir_push(-1);
  47         if (chdir(main_path)) {
  48                 perror("chdir(main path)");
  49                 goto out;
  50         }
  51
  52         ret = open(name, O_RDONLY | O_DIRECTORY);
  53         if (ret >= 0)
  54                 system_fd_set_cloexec(ret);
  55
  56 out:
  57         netifd_dir_pop(prev_dir);
  58         return ret;
  59 }
  60
  61 static void
  62 netifd_init_script_handler(const char *script, json_object *obj, script_dump_cb cb)
  63 {
  64         json_object *tmp;
  65         const char *name;
  66
  67         if (!json_check_type(obj, json_type_object))
  68                 return;
  69
  70         tmp = json_get_field(obj, "name", json_type_string);
  71         if (!tmp)
  72                 return;
  73
  74         name = json_object_get_string(tmp);
  75         cb(script, name, obj);
  76 }
  77
  78 static void
  79 netifd_parse_script_handler(const char *name, script_dump_cb cb)
  80 {
  81         struct json_tokener *tok = NULL;
  82         json_object *obj;
  83         static char buf[512];
  84         char *start, *cmd;
  85         FILE *f;
  86         int len;
  87
  88 #define DUMP_SUFFIX     " '' dump"
  89
  90         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
  91         sprintf(cmd, "%s" DUMP_SUFFIX, name);
  92
  93         f = popen(cmd, "r");
  94         if (!f)
  95                 return;
  96
  97         do {
  98                 start = fgets(buf, sizeof(buf), f);
  99                 if (!start)
 100                         continue;
 101
 102                 len = strlen(start);
 103
 104                 if (!tok)
 105                         tok = json_tokener_new();
 106
 107                 obj = json_tokener_parse_ex(tok, start, len);
 108                 if (!is_error(obj)) {
 109                         netifd_init_script_handler(name, obj, cb);
 110                         json_object_put(obj);
 111                         json_tokener_free(tok);
 112                         tok = NULL;
 113                 } else if (start[len - 1] == '\n') {
 114                         json_tokener_free(tok);
 115                         tok = NULL;
 116                 }
 117         } while (!feof(f) && !ferror(f));
 118
 119         if (tok)
 120                 json_tokener_free(tok);
 121
 122         pclose(f);
 123 }
 124
 125 void netifd_init_script_handlers(int dir_fd, script_dump_cb cb)
 126 {
 127         glob_t g;
 128         int i, prev_fd;
 129
 130         prev_fd = netifd_dir_push(dir_fd);
 131         if (glob("./*.sh", 0, NULL, &g))
 132                 return;
 133
 134         for (i = 0; i < g.gl_pathc; i++)
 135                 netifd_parse_script_handler(g.gl_pathv[i], cb);
 136         netifd_dir_pop(prev_fd);
 137
 138         globfree(&g);
 139 }
 140
 141 char *
 142 netifd_handler_parse_config(struct uci_blob_param_list *config, json_object *obj)
 143 {
 144         struct blobmsg_policy *attrs;
 145         char *str_buf, *str_cur;
 146         char const **validate;
 147         int str_len = 0;
 148         int i;
 149
 150         config->n_params = json_object_array_length(obj);
 151         attrs = calloc(1, sizeof(*attrs) * config->n_params);
 152         if (!attrs)
 153                 return NULL;
 154
 155         validate = calloc(1, sizeof(char*) * config->n_params);
 156         if (!validate)
 157                 goto error;
 158
 159         config->params = attrs;
 160         config->validate = validate;
 161         for (i = 0; i < config->n_params; i++) {
 162                 json_object *cur, *name, *type;
 163
 164                 cur = json_check_type(json_object_array_get_idx(obj, i), json_type_array);
 165                 if (!cur)
 166                         goto error;
 167
 168                 name = json_check_type(json_object_array_get_idx(cur, 0), json_type_string);
 169                 if (!name)
 170                         goto error;
 171
 172                 type = json_check_type(json_object_array_get_idx(cur, 1), json_type_int);
 173                 if (!type)
 174                         goto error;
 175
 176                 attrs[i].name = json_object_get_string(name);
 177                 attrs[i].type = json_object_get_int(type);
 178                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 179                         goto error;
 180
 181                 str_len += strlen(attrs[i].name) + 1;
 182         }
 183
 184         str_buf = malloc(str_len);
 185         if (!str_buf)
 186                 goto error;
 187
 188         str_cur = str_buf;
 189         for (i = 0; i < config->n_params; i++) {
 190                 const char *name = attrs[i].name;
 191                 char *delim;
 192
 193                 attrs[i].name = str_cur;
 194                 str_cur += sprintf(str_cur, "%s", name) + 1;
 195                 delim = strchr(attrs[i].name, ':');
 196                 if (delim) {
 197                         *delim = '\0';
 198                         validate[i] = ++delim;
 199                 } else {
 200                         validate[i] = NULL;
 201                 }
 202         }
 203
 204         return str_buf;
 205
 206 error:
 207         free(attrs);
 208         if (validate)
 209                 free(validate);
 210         config->n_params = 0;
 211         return NULL;
 212 }