From 35c0754fadca8010955f6b10cb47af00bdbe1286 Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Wed, 3 Jan 2018 10:00:08 -0500 Subject: [PATCH] Allow ldaps when using ldap authentication While ldaptls=1 provides an RFC 4513 conforming way to do LDAP authentication with TLS encryption, there was an earlier de facto standard way to do LDAP over SSL called LDAPS. Even though it's not enshrined in a standard, it's still widely used and sometimes required by organizations' network policies. There seems to be no reason not to support it when available in the client library. Therefore, add support when using OpenLDAP 2.4+ or Windows. It can be configured with ldapscheme=ldaps or ldapurl=ldaps://... Add tests for both ways of requesting LDAPS and a test for the pre-existing ldaptls=1. Modify the 001_auth.pl test for "diagnostic messages", which was previously relying on the server rejecting ldaptls=1. Author: Thomas Munro Reviewed-By: Peter Eisentraut Discussion: https://postgr.es/m/CAEepm=1s+pA-LZUjQ-9GQz0Z4rX_eK=DFXAF1nBQ+ROPimuOYQ@mail.gmail.com --- configure | 11 ++++++ configure.in | 1 + doc/src/sgml/client-auth.sgml | 50 ++++++++++++++++++++------- src/backend/libpq/auth.c | 59 ++++++++++++++++++++++++++++---- src/backend/libpq/hba.c | 16 ++++++++- src/include/libpq/hba.h | 1 + src/include/pg_config.h.in | 3 ++ src/test/ldap/t/001_auth.pl | 63 ++++++++++++++++++++++++++++++++--- 8 files changed, 179 insertions(+), 25 deletions(-) diff --git a/configure b/configure index 82f332f545..d88863e50c 100755 --- a/configure +++ b/configure @@ -10424,6 +10424,17 @@ fi else LDAP_LIBS_FE="-lldap $EXTRA_LDAP_LIBS" fi + for ac_func in ldap_initialize +do : + ac_fn_c_check_func "$LINENO" "ldap_initialize" "ac_cv_func_ldap_initialize" +if test "x$ac_cv_func_ldap_initialize" = xyes; then : + cat >>confdefs.h <<_ACEOF +#define HAVE_LDAP_INITIALIZE 1 +_ACEOF + +fi +done + else { $as_echo "$as_me:${as_lineno-$LINENO}: checking for ldap_bind in -lwldap32" >&5 $as_echo_n "checking for ldap_bind in -lwldap32... " >&6; } diff --git a/configure.in b/configure.in index 4a20c9da96..4968b67bf9 100644 --- a/configure.in +++ b/configure.in @@ -1106,6 +1106,7 @@ if test "$with_ldap" = yes ; then else LDAP_LIBS_FE="-lldap $EXTRA_LDAP_LIBS" fi + AC_CHECK_FUNCS([ldap_initialize]) else AC_CHECK_LIB(wldap32, ldap_bind, [], [AC_MSG_ERROR([library 'wldap32' is required for LDAP])]) LDAP_LIBS_FE="-lwldap32" diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml index c8a1bc79aa..53832d08e2 100644 --- a/doc/src/sgml/client-auth.sgml +++ b/doc/src/sgml/client-auth.sgml @@ -1502,19 +1502,40 @@ omicron bryanh guest1 + + ldapscheme + + + Set to ldaps to use LDAPS. This is a non-standard + way of using LDAP over SSL, supported by some LDAP server + implementations. See also the ldaptls option for + an alternative. + + + ldaptls - Set to 1 to make the connection between PostgreSQL and the - LDAP server use TLS encryption. Note that this only encrypts - the traffic to the LDAP server — the connection to the client - will still be unencrypted unless SSL is used. + Set to 1 to make the connection between PostgreSQL and the LDAP server + use TLS encryption. This uses the StartTLS + operation per RFC 4513. See also the ldapscheme + option for an alternative. + + + Note that using ldapscheme or + ldaptls only encrypts the traffic between the + PostgreSQL server and the LDAP server. The connection between the + PostgreSQL server and the PostgreSQL client will still be unencrypted + unless SSL is used there as well. + + + The following options are used in simple bind mode only: @@ -1536,7 +1557,9 @@ omicron bryanh guest1 + + The following options are used in search+bind mode only: @@ -1594,7 +1617,7 @@ omicron bryanh guest1 An RFC 4516 LDAP URL. This is an alternative way to write some of the other LDAP options in a more compact and standard form. The format is -ldap://host[:port]/basedn[?[attribute][?[scope][?[filter]]]] +ldap[s]://host[:port]/basedn[?[attribute][?[scope][?[filter]]]] scope must be one of base, one, sub, @@ -1608,16 +1631,19 @@ ldap://host[:port]/ - For non-anonymous binds, ldapbinddn - and ldapbindpasswd must be specified as separate - options. + The URL scheme ldaps chooses the LDAPS method for + making LDAP connections over SSL, equivalent to using + ldapscheme=ldaps. To use encrypted LDAP + connections using the StartTLS operation, use the + normal URL scheme ldap and specify the + ldaptls option in addition to + ldapurl. - To use encrypted LDAP connections, the ldaptls - option has to be used in addition to ldapurl. - The ldaps URL scheme (direct SSL connection) is not - supported. + For non-anonymous binds, ldapbinddn + and ldapbindpasswd must be specified as separate + options. diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c index 1d49ed784f..3560edc33a 100644 --- a/src/backend/libpq/auth.c +++ b/src/backend/libpq/auth.c @@ -2355,22 +2355,61 @@ static int errdetail_for_ldap(LDAP *ldap); static int InitializeLDAPConnection(Port *port, LDAP **ldap) { + const char *scheme; int ldapversion = LDAP_VERSION3; int r; - *ldap = ldap_init(port->hba->ldapserver, port->hba->ldapport); + scheme = port->hba->ldapscheme; + if (scheme == NULL) + scheme = "ldap"; +#ifdef WIN32 + *ldap = ldap_sslinit(port->hba->ldapserver, + port->hba->ldapport, + strcmp(scheme, "ldaps") == 0); if (!*ldap) { -#ifndef WIN32 - ereport(LOG, - (errmsg("could not initialize LDAP: %m"))); -#else ereport(LOG, (errmsg("could not initialize LDAP: error code %d", (int) LdapGetLastError()))); -#endif + return STATUS_ERROR; } +#else +#ifdef HAVE_LDAP_INITIALIZE + { + char *uri; + + uri = psprintf("%s://%s:%d", scheme, port->hba->ldapserver, + port->hba->ldapport); + r = ldap_initialize(ldap, uri); + pfree(uri); + if (r != LDAP_SUCCESS) + { + ereport(LOG, + (errmsg("could not initialize LDAP: %s", + ldap_err2string(r)))); + + return STATUS_ERROR; + } + } +#else + if (strcmp(scheme, "ldaps") == 0) + { + ereport(LOG, + (errmsg("ldaps not supported with this LDAP library"))); + + return STATUS_ERROR; + } + *ldap = ldap_init(port->hba->ldapserver, port->hba->ldapport); + if (!*ldap) + { + ereport(LOG, + (errmsg("could not initialize LDAP: %m"))); + + return STATUS_ERROR; + } +#endif +#endif if ((r = ldap_set_option(*ldap, LDAP_OPT_PROTOCOL_VERSION, &ldapversion)) != LDAP_SUCCESS) { @@ -2493,7 +2532,13 @@ CheckLDAPAuth(Port *port) } if (port->hba->ldapport == 0) - port->hba->ldapport = LDAP_PORT; + { + if (port->hba->ldapscheme != NULL && + strcmp(port->hba->ldapscheme, "ldaps") == 0) + port->hba->ldapport = LDAPS_PORT; + else + port->hba->ldapport = LDAP_PORT; + } sendAuthRequest(port, AUTH_REQ_PASSWORD, NULL, 0); diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c index f760d24886..aa20f266b8 100644 --- a/src/backend/libpq/hba.c +++ b/src/backend/libpq/hba.c @@ -1728,7 +1728,8 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, return false; } - if (strcmp(urldata->lud_scheme, "ldap") != 0) + if (strcmp(urldata->lud_scheme, "ldap") != 0 && + strcmp(urldata->lud_scheme, "ldaps") != 0) { ereport(elevel, (errcode(ERRCODE_CONFIG_FILE_ERROR), @@ -1739,6 +1740,8 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, return false; } + if (urldata->lud_scheme) + hbaline->ldapscheme = pstrdup(urldata->lud_scheme); if (urldata->lud_host) hbaline->ldapserver = pstrdup(urldata->lud_host); hbaline->ldapport = urldata->lud_port; @@ -1766,6 +1769,17 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, else hbaline->ldaptls = false; } + else if (strcmp(name, "ldapscheme") == 0) + { + REQUIRE_AUTH_OPTION(uaLDAP, "ldapscheme", "ldap"); + if (strcmp(val, "ldap") != 0 && strcmp(val, "ldaps") != 0) + ereport(elevel, + (errcode(ERRCODE_CONFIG_FILE_ERROR), + errmsg("invalid ldapscheme value: \"%s\"", val), + errcontext("line %d of configuration file \"%s\"", + line_num, HbaFileName))); + hbaline->ldapscheme = pstrdup(val); + } else if (strcmp(name, "ldapserver") == 0) { REQUIRE_AUTH_OPTION(uaLDAP, "ldapserver", "ldap"); diff --git a/src/include/libpq/hba.h b/src/include/libpq/hba.h index e711bee8bf..5f68f4c666 100644 --- a/src/include/libpq/hba.h +++ b/src/include/libpq/hba.h @@ -75,6 +75,7 @@ typedef struct HbaLine char *pamservice; bool pam_use_hostname; bool ldaptls; + char *ldapscheme; char *ldapserver; int ldapport; char *ldapbinddn; diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in index 0aa6be4666..27b1368721 100644 --- a/src/include/pg_config.h.in +++ b/src/include/pg_config.h.in @@ -310,6 +310,9 @@ /* Define to 1 if you have the header file. */ #undef HAVE_LDAP_H +/* Define to 1 if you have the `ldap_initialize' function. */ +#undef HAVE_LDAP_INITIALIZE + /* Define to 1 if you have the `crypto' library (-lcrypto). */ #undef HAVE_LIBCRYPTO diff --git a/src/test/ldap/t/001_auth.pl b/src/test/ldap/t/001_auth.pl index 38760ece61..5508da459f 100644 --- a/src/test/ldap/t/001_auth.pl +++ b/src/test/ldap/t/001_auth.pl @@ -2,7 +2,7 @@ use strict; use warnings; use TestLib; use PostgresNode; -use Test::More tests => 15; +use Test::More tests => 19; my ($slapd, $ldap_bin_dir, $ldap_schema_dir); @@ -33,13 +33,16 @@ elsif ($^O eq 'freebsd') $ENV{PATH} = "$ldap_bin_dir:$ENV{PATH}" if $ldap_bin_dir; my $ldap_datadir = "${TestLib::tmp_check}/openldap-data"; +my $slapd_certs = "${TestLib::tmp_check}/slapd-certs"; my $slapd_conf = "${TestLib::tmp_check}/slapd.conf"; my $slapd_pidfile = "${TestLib::tmp_check}/slapd.pid"; my $slapd_logfile = "${TestLib::tmp_check}/slapd.log"; my $ldap_conf = "${TestLib::tmp_check}/ldap.conf"; my $ldap_server = 'localhost'; my $ldap_port = int(rand() * 16384) + 49152; +my $ldaps_port = $ldap_port + 1; my $ldap_url = "ldap://$ldap_server:$ldap_port"; +my $ldaps_url = "ldaps://$ldap_server:$ldaps_port"; my $ldap_basedn = 'dc=example,dc=net'; my $ldap_rootdn = 'cn=Manager,dc=example,dc=net'; my $ldap_rootpw = 'secret'; @@ -63,13 +66,27 @@ access to * database ldif directory $ldap_datadir +TLSCACertificateFile $slapd_certs/ca.crt +TLSCertificateFile $slapd_certs/server.crt +TLSCertificateKeyFile $slapd_certs/server.key + suffix "dc=example,dc=net" rootdn "$ldap_rootdn" rootpw $ldap_rootpw}); -mkdir $ldap_datadir or die; +# don't bother to check the server's cert (though perhaps we should) +append_to_file($ldap_conf, +qq{TLS_REQCERT never +}); -system_or_bail $slapd, '-f', $slapd_conf, '-h', $ldap_url; +mkdir $ldap_datadir or die; +mkdir $slapd_certs or die; + +system_or_bail "openssl", "req", "-new", "-nodes", "-keyout", "$slapd_certs/ca.key", "-x509", "-out", "$slapd_certs/ca.crt", "-subj", "/cn=CA"; +system_or_bail "openssl", "req", "-new", "-nodes", "-keyout", "$slapd_certs/server.key", "-out", "$slapd_certs/server.csr", "-subj", "/cn=server"; +system_or_bail "openssl", "x509", "-req", "-in", "$slapd_certs/server.csr", "-CA", "$slapd_certs/ca.crt", "-CAkey", "$slapd_certs/ca.key", "-CAcreateserial", "-out", "$slapd_certs/server.crt"; + +system_or_bail $slapd, '-f', $slapd_conf, '-h', "$ldap_url $ldaps_url"; END { @@ -81,6 +98,7 @@ chmod 0600, $ldap_pwfile or die; $ENV{'LDAPURI'} = $ldap_url; $ENV{'LDAPBINDDN'} = $ldap_rootdn; +$ENV{'LDAPCONF'} = $ldap_conf; note "loading LDAP data"; @@ -178,9 +196,44 @@ test_access($node, 'test1', 0, 'combined LDAP URL and search filter'); note "diagnostic message"; +# note bad ldapprefix with a question mark that triggers a diagnostic message unlink($node->data_dir . '/pg_hba.conf'); -$node->append_conf('pg_hba.conf', qq{local all all ldap ldapserver=$ldap_server ldapport=$ldap_port ldapprefix="uid=" ldapsuffix=",dc=example,dc=net" ldaptls=1}); +$node->append_conf('pg_hba.conf', qq{local all all ldap ldapserver=$ldap_server ldapport=$ldap_port ldapprefix="?uid=" ldapsuffix=""}); $node->reload; $ENV{"PGPASSWORD"} = 'secret1'; -test_access($node, 'test1', 2, 'any attempt fails due to unsupported TLS'); +test_access($node, 'test1', 2, 'any attempt fails due to bad search pattern'); + +note "TLS"; + +# request StartTLS with ldaptls=1 +unlink($node->data_dir . '/pg_hba.conf'); +$node->append_conf('pg_hba.conf', qq{local all all ldap ldapserver=$ldap_server ldapport=$ldap_port ldapbasedn="$ldap_basedn" ldapsearchfilter="(uid=\$username)" ldaptls=1}); +$node->reload; + +$ENV{"PGPASSWORD"} = 'secret1'; +test_access($node, 'test1', 0, 'StartTLS'); + +# request LDAPS with ldapscheme=ldaps +unlink($node->data_dir . '/pg_hba.conf'); +$node->append_conf('pg_hba.conf', qq{local all all ldap ldapserver=$ldap_server ldapscheme=ldaps ldapport=$ldaps_port ldapbasedn="$ldap_basedn" ldapsearchfilter="(uid=\$username)"}); +$node->reload; + +$ENV{"PGPASSWORD"} = 'secret1'; +test_access($node, 'test1', 0, 'LDAPS'); + +# request LDAPS with ldapurl=ldaps://... +unlink($node->data_dir . '/pg_hba.conf'); +$node->append_conf('pg_hba.conf', qq{local all all ldap ldapurl="$ldaps_url/$ldap_basedn??sub?(uid=\$username)"}); +$node->reload; + +$ENV{"PGPASSWORD"} = 'secret1'; +test_access($node, 'test1', 0, 'LDAPS with URL'); + +# bad combination of LDAPS and StartTLS +unlink($node->data_dir . '/pg_hba.conf'); +$node->append_conf('pg_hba.conf', qq{local all all ldap ldapurl="$ldaps_url/$ldap_basedn??sub?(uid=\$username)" ldaptls=1}); +$node->reload; + +$ENV{"PGPASSWORD"} = 'secret1'; +test_access($node, 'test1', 2, 'bad combination of LDAPS and StartTLS');