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()
  50                 {
  51                 conn = NULL;
  52                 Implementation eventlist[] = { I_OnUserDisconnect, I_OnCheckReady, I_OnRehash, I_OnUserRegister };
  53                 ServerInstance->Modules->Attach(eventlist, this, 4);
  54                 OnRehash(NULL);
  55         }
  56
  57         virtual ~ModuleLDAPAuth()
  58         {
  59                 if (conn)
  60                         ldap_unbind_ext(conn, NULL, NULL);
  61         }
  62
  63         virtual void OnRehash(User* user)
  64         {
  65                 ConfigReader Conf;
  66
  67                 base                    = Conf.ReadValue("ldapauth", "baserdn", 0);
  68                 attribute               = Conf.ReadValue("ldapauth", "attribute", 0);
  69                 ldapserver              = Conf.ReadValue("ldapauth", "server", 0);
  70                 allowpattern            = Conf.ReadValue("ldapauth", "allowpattern", 0);
  71                 killreason              = Conf.ReadValue("ldapauth", "killreason", 0);
  72                 std::string scope       = Conf.ReadValue("ldapauth", "searchscope", 0);
  73                 username                = Conf.ReadValue("ldapauth", "binddn", 0);
  74                 password                = Conf.ReadValue("ldapauth", "bindauth", 0);
  75                 verbose                 = Conf.ReadFlag("ldapauth", "verbose", 0);              /* Set to true if failed connects should be reported to operators */
  76                 useusername             = Conf.ReadFlag("ldapauth", "userfield", 0);
  77
  78                 if (scope == "base")
  79                         searchscope = LDAP_SCOPE_BASE;
  80                 else if (scope == "onelevel")
  81                         searchscope = LDAP_SCOPE_ONELEVEL;
  82                 else searchscope = LDAP_SCOPE_SUBTREE;
  83
  84                 Connect();
  85         }
  86
  87         bool Connect()
  88         {
  89                 if (conn != NULL)
  90                         ldap_unbind_ext(conn, NULL, NULL);
  91                 int res, v = LDAP_VERSION3;
  92                 res = ldap_initialize(&conn, ldapserver.c_str());
  93                 if (res != LDAP_SUCCESS)
  94                 {
  95                         if (verbose)
  96                                 ServerInstance->SNO->WriteToSnoMask('c', "LDAP connection failed: %s", ldap_err2string(res));
  97                         conn = NULL;
  98                         return false;
  99                 }
 100
 101                 res = ldap_set_option(conn, LDAP_OPT_PROTOCOL_VERSION, (void *)&v);
 102                 if (res != LDAP_SUCCESS)
 103                 {
 104                         if (verbose)
 105                                 ServerInstance->SNO->WriteToSnoMask('c', "LDAP set protocol to v3 failed: %s", ldap_err2string(res));
 106                         ldap_unbind_ext(conn, NULL, NULL);
 107                         conn = NULL;
 108                         return false;
 109                 }
 110                 return true;
 111         }
 112
 113         virtual ModResult OnUserRegister(User* user)
 114         {
 115                 if ((!allowpattern.empty()) && (InspIRCd::Match(user->nick,allowpattern)))
 116                 {
 117                         user->Extend("ldapauthed");
 118                         return MOD_RES_PASSTHRU;
 119                 }
 120
 121                 if (!CheckCredentials(user))
 122                 {
 123                         ServerInstance->Users->QuitUser(user, killreason);
 124                         return MOD_RES_DENY;
 125                 }
 126                 return MOD_RES_PASSTHRU;
 127         }
 128
 129         bool CheckCredentials(User* user)
 130         {
 131                 if (conn == NULL)
 132                         if (!Connect())
 133                                 return false;
 134
 135                 int res;
 136                 char* authpass = strdup(password.c_str());
 137                 // bind anonymously if no bind DN and authentication are given in the config
 138                 struct berval cred;
 139                 cred.bv_val = authpass;
 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                                 free(authpass);
 158                                 ldap_unbind_ext(conn, NULL, NULL);
 159                                 conn = NULL;
 160                                 return false;
 161                         }
 162                 }
 163                 free(authpass);
 164
 165                 LDAPMessage *msg, *entry;
 166                 std::string what = (attribute + "=" + (useusername ? user->ident : user->nick));
 167                 if ((res = ldap_search_ext_s(conn, base.c_str(), searchscope, what.c_str(), NULL, 0, NULL, NULL, NULL, 0, &msg)) != LDAP_SUCCESS)
 168                 {
 169                         if (verbose)
 170                                 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));
 171                         return false;
 172                 }
 173                 if (ldap_count_entries(conn, msg) > 1)
 174                 {
 175                         if (verbose)
 176                                 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));
 177                         ldap_msgfree(msg);
 178                         return false;
 179                 }
 180                 if ((entry = ldap_first_entry(conn, msg)) == NULL)
 181                 {
 182                         if (verbose)
 183                                 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));
 184                         ldap_msgfree(msg);
 185                         return false;
 186                 }
 187                 if (user->password.empty())
 188                 {
 189                         if (verbose)
 190                                 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());
 191                         user->Extend("ldapauth_failed");
 192                         return false;
 193                 }
 194                 cred.bv_val = (char*)user->password.data();
 195                 cred.bv_len = user->password.length();
 196                 if ((res = ldap_sasl_bind_s(conn, ldap_get_dn(conn, entry), LDAP_SASL_SIMPLE, &cred, NULL, NULL, NULL)) == LDAP_SUCCESS)
 197                 {
 198                         ldap_msgfree(msg);
 199                         user->Extend("ldapauthed");
 200                         return true;
 201                 }
 202                 else
 203                 {
 204                         if (verbose)
 205                                 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));
 206                         ldap_msgfree(msg);
 207                         user->Extend("ldapauth_failed");
 208                         return false;
 209                 }
 210         }
 211
 212
 213         virtual void OnUserDisconnect(User* user)
 214         {
 215                 user->Shrink("ldapauthed");
 216                 user->Shrink("ldapauth_failed");
 217         }
 218
 219         virtual ModResult OnCheckReady(User* user)
 220         {
 221                 return user->GetExt("ldapauthed") ? MOD_RES_PASSTHRU : MOD_RES_DENY;
 222         }
 223
 224         virtual Version GetVersion()
 225         {
 226                 return Version("Allow/Deny connections based upon answer from LDAP server", VF_VENDOR, API_VERSION);
 227         }
 228
 229 };
 230
 231 MODULE_INIT(ModuleLDAPAuth)