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         std::string base;
  37         std::string attribute;
  38         std::string ldapserver;
  39         std::string allowpattern;
  40         std::string killreason;
  41         std::string username;
  42         std::string password;
  43         int searchscope;
  44         bool verbose;
  45         bool useusername;
  46         LDAP *conn;
  47
  48 public:
  49         ModuleLDAPAuth(InspIRCd* Me)
  50         : Module(Me)
  51         {
  52                 conn = NULL;
  53                 Implementation eventlist[] = { I_OnUserDisconnect, I_OnCheckReady, I_OnRehash, I_OnUserRegister };
  54                 ServerInstance->Modules->Attach(eventlist, this, 4);
  55                 OnRehash(NULL);
  56         }
  57
  58         virtual ~ModuleLDAPAuth()
  59         {
  60                 if (conn)
  61                         ldap_unbind_ext(conn, NULL, NULL);
  62         }
  63
  64         virtual void OnRehash(User* user)
  65         {
  66                 ConfigReader Conf(ServerInstance);
  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         virtual ModResult OnUserRegister(User* user)
 115         {
 116                 if ((!allowpattern.empty()) && (InspIRCd::Match(user->nick,allowpattern)))
 117                 {
 118                         user->Extend("ldapauthed");
 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(User* user)
 131         {
 132                 if (conn == NULL)
 133                         if (!Connect())
 134                                 return false;
 135
 136                 int res;
 137                 char* authpass = strdup(password.c_str());
 138                 // bind anonymously if no bind DN and authentication are given in the config
 139                 struct berval cred;
 140                 cred.bv_val = authpass;
 141                 cred.bv_len = password.length();
 142
 143                 if ((res = ldap_sasl_bind_s(conn, username.c_str(), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL)) != LDAP_SUCCESS)
 144                 {
 145                         if (res == LDAP_SERVER_DOWN)
 146                         {
 147                                 // Attempt to reconnect if the connection dropped
 148                                 if (verbose)
 149                                         ServerInstance->SNO->WriteToSnoMask('a', "LDAP server has gone away - reconnecting...");
 150                                 Connect();
 151                                 res = ldap_sasl_bind_s(conn, username.c_str(), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL);
 152                         }
 153
 154                         if (res != LDAP_SUCCESS)
 155                         {
 156                                 if (verbose)
 157                                         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));
 158                                 free(authpass);
 159                                 ldap_unbind_ext(conn, NULL, NULL);
 160                                 conn = NULL;
 161                                 return false;
 162                         }
 163                 }
 164                 free(authpass);
 165
 166                 LDAPMessage *msg, *entry;
 167                 std::string what = (attribute + "=" + (useusername ? user->ident : user->nick));
 168                 if ((res = ldap_search_ext_s(conn, base.c_str(), searchscope, what.c_str(), NULL, 0, NULL, NULL, NULL, 0, &msg)) != LDAP_SUCCESS)
 169                 {
 170                         if (verbose)
 171                                 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));
 172                         return false;
 173                 }
 174                 if (ldap_count_entries(conn, msg) > 1)
 175                 {
 176                         if (verbose)
 177                                 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));
 178                         ldap_msgfree(msg);
 179                         return false;
 180                 }
 181                 if ((entry = ldap_first_entry(conn, msg)) == NULL)
 182                 {
 183                         if (verbose)
 184                                 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));
 185                         ldap_msgfree(msg);
 186                         return false;
 187                 }
 188                 if (user->password.empty())
 189                 {
 190                         if (verbose)
 191                                 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());
 192                         user->Extend("ldapauth_failed");
 193                         return false;
 194                 }
 195                 cred.bv_val = (char*)user->password.data();
 196                 cred.bv_len = user->password.length();
 197                 if ((res = ldap_sasl_bind_s(conn, ldap_get_dn(conn, entry), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL)) == LDAP_SUCCESS)
 198                 {
 199                         ldap_msgfree(msg);
 200                         user->Extend("ldapauthed");
 201                         return true;
 202                 }
 203                 else
 204                 {
 205                         if (verbose)
 206                                 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));
 207                         ldap_msgfree(msg);
 208                         user->Extend("ldapauth_failed");
 209                         return false;
 210                 }
 211         }
 212
 213
 214         virtual void OnUserDisconnect(User* user)
 215         {
 216                 user->Shrink("ldapauthed");
 217                 user->Shrink("ldapauth_failed");
 218         }
 219
 220         virtual ModResult OnCheckReady(User* user)
 221         {
 222                 return user->GetExt("ldapauthed") ? MOD_RES_PASSTHRU : MOD_RES_DENY;
 223         }
 224
 225         virtual Version GetVersion()
 226         {
 227                 return Version("Allow/Deny connections based upon answer from LDAP server", VF_VENDOR, API_VERSION);
 228         }
 229
 230 };
 231
 232 MODULE_INIT(ModuleLDAPAuth)