src/util.c

   1 /*
   2  * Copyright (c) 2014 Ian Sutton <ian@kremlin.cc>
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include <unistd.h>
  18 #include <limits.h>
  19 #include <string.h>
  20
  21 #include <glib/gprintf.h>
  22 #include <glib-unix.h>
  23 #include <polkit/polkit.h>
  24
  25 #include "util.h"
  26
  27 const gint MAX_TOKENS = 20;
  28
  29 /* return must be g_free()'d */
  30 gchar *config_get(const gchar *path, gchar *key) {
  31
  32     gchar  *content, **split_content, *cur, **cur_split, *ret;
  33     GError *err;
  34     int incr = 0;
  35     gboolean breaker = TRUE;
  36
  37     ret = (gchar *) g_malloc0(4096);
  38
  39     if(!g_file_get_contents(path, &content, NULL, &err))
  40         return NULL;
  41
  42     split_content = g_strsplit(content, "\n", MAX_TOKENS);
  43
  44     while(breaker && (cur = split_content[incr]) && (cur_split = g_strsplit(cur, "=", 2))) {
  45
  46         if(!g_strcmp0(key, cur_split[0])) {
  47
  48             g_strlcpy(ret, cur_split[1], 2048);
  49             breaker = FALSE;
  50         }
  51
  52         incr++;
  53         g_strfreev(cur_split);
  54     }
  55
  56     if(split_content)
  57         g_strfreev(split_content);
  58     if(content)
  59         g_free(content);
  60
  61     return (ret ? ret : NULL);
  62 }
  63
  64 gboolean config_set(const gchar *path, gchar *key, gchar *value) {
  65
  66     gchar  *content, **split_content, *cur, **cur_split, *rewrite;
  67     GError *err_set, *err_get;
  68     gboolean ret = FALSE;
  69     int incr = 0;
  70     gboolean breaker = TRUE;
  71
  72     err_get = err_set = NULL;
  73
  74     if(!g_file_get_contents(path, &content, NULL, &err_get))
  75         return FALSE;
  76
  77     split_content = g_strsplit(content, "\n", MAX_TOKENS);
  78
  79     while(breaker && (cur = split_content[incr]) && (cur_split = g_strsplit(cur, "=", 2))) {
  80
  81         if(!g_strcmp0(key, cur_split[0])) {
  82
  83             cur_split[1] = value;
  84             split_content[incr] = g_strjoinv("=", cur_split);
  85             ret = TRUE;
  86             breaker = FALSE;
  87         }
  88
  89         incr++;
  90     }
  91
  92     if(ret) {
  93
  94         rewrite = g_strjoinv("\n", split_content);
  95         ret = g_file_set_contents(path, rewrite, -1, &err_set);
  96         g_free(rewrite);
  97     }
  98
  99     if(cur_split)
 100         g_strfreev(cur_split);
 101     if(split_content)
 102         g_strfreev(split_content);
 103     if(content)
 104         g_free(content);
 105
 106     return ret;
 107 }
 108
 109 static gboolean is_valid_action(GList *action_list, const gchar *action) {
 110
 111     PolkitActionDescription *action_descr;
 112     const gchar *action_descr_id;
 113     GList *cur;
 114     gboolean ret;
 115
 116     ret = FALSE;
 117     cur = g_list_first(action_list);
 118
 119     while(cur && (action_descr = ((PolkitActionDescription *)(cur->data))) && (action_descr_id = polkit_action_description_get_action_id(action_descr))) {
 120
 121         if(!g_strcmp0(action, action_descr_id)) {
 122             ret = TRUE;
 123             break;
 124         }
 125
 126         cur = cur->next;
 127     }
 128
 129     g_list_free(action_list);
 130
 131     return ret;
 132 }
 133
 134 check_auth_result polkit_try_auth(const gchar *bus, const gchar *action, gboolean prompt) {
 135
 136     GList           *valid_actions;
 137     PolkitAuthority *auth;
 138     PolkitSubject   *subj;
 139     PolkitAuthorizationResult *result;
 140     PolkitCheckAuthorizationFlags prompt_flag;
 141     gboolean authorized, challenge;
 142
 143     auth  = NULL;
 144     subj  = NULL;
 145     result = NULL;
 146     valid_actions = NULL;
 147     authorized = challenge = FALSE;
 148     prompt_flag = prompt ? POLKIT_CHECK_AUTHORIZATION_FLAGS_ALLOW_USER_INTERACTION : POLKIT_CHECK_AUTHORIZATION_FLAGS_NONE;
 149
 150     auth = polkit_authority_get_sync(NULL, NULL); /* TODO timeout for this */
 151     subj = polkit_system_bus_name_new(bus);
 152     valid_actions = polkit_authority_enumerate_actions_sync(auth, NULL, NULL);
 153
 154    if(!auth || !valid_actions)
 155         return ERROR_GENERIC; /* extremely unlikely */
 156     else if(!subj)
 157         return ERROR_BADBUS;
 158     else if(!is_valid_action(valid_actions, action))
 159         return ERROR_BADACTION;
 160
 161    if(!(result = polkit_authority_check_authorization_sync(auth, subj, action, NULL, prompt_flag, NULL, NULL)))
 162         return ERROR_GENERIC; /* TODO pass, check gerror and return more relevant error */
 163
 164     authorized = polkit_authorization_result_get_is_authorized(result);
 165     challenge = polkit_authorization_result_get_is_challenge(result);
 166
 167     /* free()'s before return */
 168     if(auth)
 169         g_object_unref(auth);
 170     if(subj)
 171         g_object_unref(subj);
 172     if(result)
 173         g_object_unref(result);
 174
 175     if(authorized) {
 176
 177         if(challenge)
 178             return AUTHORIZED_BY_PROMPT;
 179
 180         return AUTHORIZED_NATIVELY;
 181
 182     } else if(challenge)
 183         return UNAUTHORIZED_FAILED_PROMPT;
 184
 185     return UNAUTHORIZED_NATIVELY;
 186 }