src/modules/extra/m_ldapauth.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  *
  13  * Taken from the UnrealIRCd 4.0 SVN version, based on
  14  * InspIRCd 1.1.x.
  15  *
  16  * UnrealIRCd 4.0 (C) 2007 Carsten Valdemar Munk
  17  * This program is free but copyrighted software; see
  18  *          the file COPYING for details.
  19  *
  20  * ---------------------------------------------------
  21  * Heavily based on SQLauth
  22  */
  23
  24 #include "inspircd.h"
  25 #include "users.h"
  26 #include "channels.h"
  27 #include "modules.h"
  28
  29 #include <ldap.h>
  30
  31 /* $ModDesc: Allow/Deny connections based upon answer from LDAP server */
  32 /* $LinkerFlags: -lldap */
  33
  34 class ModuleLDAPAuth : public Module
  35 {
  36         LocalIntExt ldapAuthed;
  37         std::string base;
  38         std::string attribute;
  39         std::string ldapserver;
  40         std::string allowpattern;
  41         std::string killreason;
  42         std::string username;
  43         std::string password;
  44         int searchscope;
  45         bool verbose;
  46         bool useusername;
  47         LDAP *conn;
  48
  49 public:
  50         ModuleLDAPAuth() : ldapAuthed("ldapauth", this)
  51         {
  52                 conn = NULL;
  53                 Implementation eventlist[] = { I_OnCheckReady, I_OnRehash, I_OnUserRegister };
  54                 ServerInstance->Modules->Attach(eventlist, this, 4);
  55                 OnRehash(NULL);
  56         }
  57
  58         ~ModuleLDAPAuth()
  59         {
  60                 if (conn)
  61                         ldap_unbind_ext(conn, NULL, NULL);
  62         }
  63
  64         void OnRehash(User* user)
  65         {
  66                 ConfigReader Conf;
  67
  68                 base                    = Conf.ReadValue("ldapauth", "baserdn", 0);
  69                 attribute               = Conf.ReadValue("ldapauth", "attribute", 0);
  70                 ldapserver              = Conf.ReadValue("ldapauth", "server", 0);
  71                 allowpattern            = Conf.ReadValue("ldapauth", "allowpattern", 0);
  72                 killreason              = Conf.ReadValue("ldapauth", "killreason", 0);
  73                 std::string scope       = Conf.ReadValue("ldapauth", "searchscope", 0);
  74                 username                = Conf.ReadValue("ldapauth", "binddn", 0);
  75                 password                = Conf.ReadValue("ldapauth", "bindauth", 0);
  76                 verbose                 = Conf.ReadFlag("ldapauth", "verbose", 0);              /* Set to true if failed connects should be reported to operators */
  77                 useusername             = Conf.ReadFlag("ldapauth", "userfield", 0);
  78
  79                 if (scope == "base")
  80                         searchscope = LDAP_SCOPE_BASE;
  81                 else if (scope == "onelevel")
  82                         searchscope = LDAP_SCOPE_ONELEVEL;
  83                 else searchscope = LDAP_SCOPE_SUBTREE;
  84
  85                 Connect();
  86         }
  87
  88         bool Connect()
  89         {
  90                 if (conn != NULL)
  91                         ldap_unbind_ext(conn, NULL, NULL);
  92                 int res, v = LDAP_VERSION3;
  93                 res = ldap_initialize(&conn, ldapserver.c_str());
  94                 if (res != LDAP_SUCCESS)
  95                 {
  96                         if (verbose)
  97                                 ServerInstance->SNO->WriteToSnoMask('c', "LDAP connection failed: %s", ldap_err2string(res));
  98                         conn = NULL;
  99                         return false;
 100                 }
 101
 102                 res = ldap_set_option(conn, LDAP_OPT_PROTOCOL_VERSION, (void *)&v);
 103                 if (res != LDAP_SUCCESS)
 104                 {
 105                         if (verbose)
 106                                 ServerInstance->SNO->WriteToSnoMask('c', "LDAP set protocol to v3 failed: %s", ldap_err2string(res));
 107                         ldap_unbind_ext(conn, NULL, NULL);
 108                         conn = NULL;
 109                         return false;
 110                 }
 111                 return true;
 112         }
 113
 114         ModResult OnUserRegister(LocalUser* user)
 115         {
 116                 if ((!allowpattern.empty()) && (InspIRCd::Match(user->nick,allowpattern)))
 117                 {
 118                         ldapAuthed.set(user,1);
 119                         return MOD_RES_PASSTHRU;
 120                 }
 121
 122                 if (!CheckCredentials(user))
 123                 {
 124                         ServerInstance->Users->QuitUser(user, killreason);
 125                         return MOD_RES_DENY;
 126                 }
 127                 return MOD_RES_PASSTHRU;
 128         }
 129
 130         bool CheckCredentials(LocalUser* user)
 131         {
 132                 if (conn == NULL)
 133                         if (!Connect())
 134                                 return false;
 135
 136                 int res;
 137                 // bind anonymously if no bind DN and authentication are given in the config
 138                 struct berval cred;
 139                 cred.bv_val = const_cast<char*>(password.c_str());
 140                 cred.bv_len = password.length();
 141
 142                 if ((res = ldap_sasl_bind_s(conn, username.c_str(), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL)) != LDAP_SUCCESS)
 143                 {
 144                         if (res == LDAP_SERVER_DOWN)
 145                         {
 146                                 // Attempt to reconnect if the connection dropped
 147                                 if (verbose)
 148                                         ServerInstance->SNO->WriteToSnoMask('a', "LDAP server has gone away - reconnecting...");
 149                                 Connect();
 150                                 res = ldap_sasl_bind_s(conn, username.c_str(), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL);
 151                         }
 152
 153                         if (res != LDAP_SUCCESS)
 154                         {
 155                                 if (verbose)
 156                                         ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (LDAP bind failed: %s)", user->nick.c_str(), user->ident.c_str(), user->host.c_str(), ldap_err2string(res));
 157                                 ldap_unbind_ext(conn, NULL, NULL);
 158                                 conn = NULL;
 159                                 return false;
 160                         }
 161                 }
 162
 163                 LDAPMessage *msg, *entry;
 164                 std::string what = (attribute + "=" + (useusername ? user->ident : user->nick));
 165                 if ((res = ldap_search_ext_s(conn, base.c_str(), searchscope, what.c_str(), NULL, 0, NULL, NULL, NULL, 0, &msg)) != LDAP_SUCCESS)
 166                 {
 167                         if (verbose)
 168                                 ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (LDAP search failed: %s)", user->nick.c_str(), user->ident.c_str(), user->host.c_str(), ldap_err2string(res));
 169                         return false;
 170                 }
 171                 if (ldap_count_entries(conn, msg) > 1)
 172                 {
 173                         if (verbose)
 174                                 ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (LDAP search returned more than one result: %s)", user->nick.c_str(), user->ident.c_str(), user->host.c_str(), ldap_err2string(res));
 175                         ldap_msgfree(msg);
 176                         return false;
 177                 }
 178                 if ((entry = ldap_first_entry(conn, msg)) == NULL)
 179                 {
 180                         if (verbose)
 181                                 ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (LDAP search returned no results: %s)", user->nick.c_str(), user->ident.c_str(), user->host.c_str(), ldap_err2string(res));
 182                         ldap_msgfree(msg);
 183                         return false;
 184                 }
 185                 if (user->password.empty())
 186                 {
 187                         if (verbose)
 188                                 ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (No password provided)", user->nick.c_str(), user->ident.c_str(), user->host.c_str());
 189                         return false;
 190                 }
 191                 cred.bv_val = (char*)user->password.data();
 192                 cred.bv_len = user->password.length();
 193                 if ((res = ldap_sasl_bind_s(conn, ldap_get_dn(conn, entry), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL)) == LDAP_SUCCESS)
 194                 {
 195                         ldap_msgfree(msg);
 196                         ldapAuthed.set(user,1);
 197                         return true;
 198                 }
 199                 else
 200                 {
 201                         if (verbose)
 202                                 ServerInstance->SNO->WriteToSnoMask('c', "Forbidden connection from %s!%s@%s (%s)", user->nick.c_str(), user->ident.c_str(), user->host.c_str(), ldap_err2string(res));
 203                         ldap_msgfree(msg);
 204                         return false;
 205                 }
 206         }
 207
 208         ModResult OnCheckReady(LocalUser* user)
 209         {
 210                 return ldapAuthed.get(user) ? MOD_RES_PASSTHRU : MOD_RES_DENY;
 211         }
 212
 213         Version GetVersion()
 214         {
 215                 return Version("Allow/Deny connections based upon answer from LDAP server", VF_VENDOR);
 216         }
 217
 218 };
 219
 220 MODULE_INIT(ModuleLDAPAuth)