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 (prev_fd < 0)
  38                 return;
  39
  40         if (fchdir(prev_fd)) {}
  41         close(prev_fd);
  42 }
  43
  44 int netifd_open_subdir(const char *name)
  45 {
  46         int prev_dir;
  47         int ret = -1;
  48
  49         prev_dir = netifd_dir_push(-1);
  50         if (chdir(main_path)) {
  51                 perror("chdir(main path)");
  52                 goto out;
  53         }
  54
  55         ret = open(name, O_RDONLY | O_DIRECTORY);
  56         if (ret >= 0)
  57                 system_fd_set_cloexec(ret);
  58
  59 out:
  60         netifd_dir_pop(prev_dir);
  61         return ret;
  62 }
  63
  64 static void
  65 netifd_init_script_handler(const char *script, json_object *obj, script_dump_cb cb)
  66 {
  67         json_object *tmp;
  68         const char *name;
  69
  70         if (!json_check_type(obj, json_type_object))
  71                 return;
  72
  73         tmp = json_get_field(obj, "name", json_type_string);
  74         if (!tmp)
  75                 return;
  76
  77         name = json_object_get_string(tmp);
  78         cb(script, name, obj);
  79 }
  80
  81 static void
  82 netifd_parse_script_handler(const char *name, script_dump_cb cb)
  83 {
  84         struct json_tokener *tok = NULL;
  85         json_object *obj;
  86         static char buf[512];
  87         char *start, *cmd;
  88         FILE *f;
  89         int len;
  90
  91 #define DUMP_SUFFIX     " '' dump"
  92
  93         cmd = alloca(strlen(name) + 1 + sizeof(DUMP_SUFFIX));
  94         sprintf(cmd, "%s" DUMP_SUFFIX, name);
  95
  96         f = popen(cmd, "r");
  97         if (!f)
  98                 return;
  99
 100         do {
 101                 start = fgets(buf, sizeof(buf), f);
 102                 if (!start)
 103                         continue;
 104
 105                 len = strlen(start);
 106
 107                 if (!tok)
 108                         tok = json_tokener_new();
 109
 110                 obj = json_tokener_parse_ex(tok, start, len);
 111                 if (obj) {
 112                         netifd_init_script_handler(name, obj, cb);
 113                         json_object_put(obj);
 114                         json_tokener_free(tok);
 115                         tok = NULL;
 116                 } else if (start[len - 1] == '\n') {
 117                         json_tokener_free(tok);
 118                         tok = NULL;
 119                 }
 120         } while (!feof(f) && !ferror(f));
 121
 122         if (tok)
 123                 json_tokener_free(tok);
 124
 125         pclose(f);
 126 }
 127
 128 void netifd_init_script_handlers(int dir_fd, script_dump_cb cb)
 129 {
 130         glob_t g;
 131         int i, prev_fd;
 132
 133         prev_fd = netifd_dir_push(dir_fd);
 134         if (glob("./*.sh", 0, NULL, &g)) {
 135                 netifd_dir_pop(prev_fd);
 136                 return;
 137         }
 138
 139         for (i = 0; i < g.gl_pathc; i++)
 140                 netifd_parse_script_handler(g.gl_pathv[i], cb);
 141         netifd_dir_pop(prev_fd);
 142
 143         globfree(&g);
 144 }
 145
 146 char *
 147 netifd_handler_parse_config(struct uci_blob_param_list *config, json_object *obj)
 148 {
 149         struct blobmsg_policy *attrs;
 150         char *str_buf, *str_cur;
 151         char const **validate;
 152         int str_len = 0;
 153         int i;
 154
 155         config->n_params = json_object_array_length(obj);
 156         attrs = calloc(1, sizeof(*attrs) * config->n_params);
 157         if (!attrs)
 158                 return NULL;
 159
 160         validate = calloc(1, sizeof(char*) * config->n_params);
 161         if (!validate)
 162                 goto error;
 163
 164         config->params = attrs;
 165         config->validate = validate;
 166         for (i = 0; i < config->n_params; i++) {
 167                 json_object *cur, *name, *type;
 168
 169                 cur = json_check_type(json_object_array_get_idx(obj, i), json_type_array);
 170                 if (!cur)
 171                         goto error;
 172
 173                 name = json_check_type(json_object_array_get_idx(cur, 0), json_type_string);
 174                 if (!name)
 175                         goto error;
 176
 177                 type = json_check_type(json_object_array_get_idx(cur, 1), json_type_int);
 178                 if (!type)
 179                         goto error;
 180
 181                 attrs[i].name = json_object_get_string(name);
 182                 attrs[i].type = json_object_get_int(type);
 183                 if (attrs[i].type > BLOBMSG_TYPE_LAST)
 184                         goto error;
 185
 186                 str_len += strlen(attrs[i].name) + 1;
 187         }
 188
 189         str_buf = malloc(str_len);
 190         if (!str_buf)
 191                 goto error;
 192
 193         str_cur = str_buf;
 194         for (i = 0; i < config->n_params; i++) {
 195                 const char *name = attrs[i].name;
 196                 char *delim;
 197
 198                 attrs[i].name = str_cur;
 199                 str_cur += sprintf(str_cur, "%s", name) + 1;
 200                 delim = strchr(attrs[i].name, ':');
 201                 if (delim) {
 202                         *delim = '\0';
 203                         validate[i] = ++delim;
 204                 } else {
 205                         validate[i] = NULL;
 206                 }
 207         }
 208
 209         return str_buf;
 210
 211 error:
 212         free(attrs);
 213         if (validate)
 214                 free(validate);
 215         config->n_params = 0;
 216         return NULL;
 217 }