From 919c9f6cceeae8468672462a23eab470e18ceda0 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 3 Jan 2008 21:27:59 +0000 Subject: [PATCH] The original patch to disallow non-passworded connections to non-superusers failed to cover all the ways in which a connection can be initiated in dblink. Plug the remaining holes. Also, disallow transient connections in functions for which that feature makes no sense (because they are only sensible as part of a sequence of operations on the same connection). Joe Conway Security: CVE-2007-6601 --- contrib/dblink/dblink.c | 78 +++++++++++++++--------------- contrib/dblink/expected/dblink.out | 37 ++++++++++++++ contrib/dblink/sql/dblink.sql | 9 ++++ 3 files changed, 86 insertions(+), 38 deletions(-) diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c index 0376345d81..92891a0355 100644 --- a/contrib/dblink/dblink.c +++ b/contrib/dblink/dblink.c @@ -8,7 +8,7 @@ * Darko Prenosil * Shridhar Daithankar * - * $PostgreSQL: pgsql/contrib/dblink/dblink.c,v 1.67 2008/01/01 19:45:45 momjian Exp $ + * $PostgreSQL: pgsql/contrib/dblink/dblink.c,v 1.68 2008/01/03 21:27:59 tgl Exp $ * Copyright (c) 2001-2008, PostgreSQL Global Development Group * ALL RIGHTS RESERVED; * @@ -91,6 +91,7 @@ static int16 get_attnum_pk_pos(int2vector *pkattnums, int16 pknumatts, int16 key static HeapTuple get_tuple_of_interest(Oid relid, int2vector *pkattnums, int16 pknumatts, char **src_pkattvals); static Oid get_relid_from_relname(text *relname_text); static char *generate_relation_name(Oid relid); +static void dblink_security_check(PGconn *conn, remoteConn *rconn); /* Global */ static remoteConn *pconn = NULL; @@ -187,10 +188,21 @@ typedef struct remoteConnHashEnt errmsg("could not establish connection"), \ errdetail("%s", msg))); \ } \ + dblink_security_check(conn, rconn); \ freeconn = true; \ } \ } while (0) +#define DBLINK_GET_NAMED_CONN \ + do { \ + char *conname = GET_STR(PG_GETARG_TEXT_P(0)); \ + rconn = getConnectionByName(conname); \ + if(rconn) \ + conn = rconn->conn; \ + else \ + DBLINK_CONN_NOT_AVAIL; \ + } while (0) + #define DBLINK_INIT \ do { \ if (!pconn) \ @@ -247,21 +259,8 @@ dblink_connect(PG_FUNCTION_ARGS) errdetail("%s", msg))); } - if (!superuser()) - { - if (!PQconnectionUsedPassword(conn)) - { - PQfinish(conn); - if (rconn) - pfree(rconn); - - ereport(ERROR, - (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED), - errmsg("password is required"), - errdetail("Non-superuser cannot connect if the server does not request a password."), - errhint("Target server's authentication method must be changed."))); - } - } + /* check password used if not superuser */ + dblink_security_check(conn, rconn); if (connname) { @@ -1047,17 +1046,11 @@ PG_FUNCTION_INFO_V1(dblink_is_busy); Datum dblink_is_busy(PG_FUNCTION_ARGS) { - char *msg; PGconn *conn = NULL; - char *conname = NULL; - char *connstr = NULL; remoteConn *rconn = NULL; - bool freeconn = false; DBLINK_INIT; - DBLINK_GET_CONN; - if (!conn) - DBLINK_CONN_NOT_AVAIL; + DBLINK_GET_NAMED_CONN; PQconsumeInput(conn); PG_RETURN_INT32(PQisBusy(conn)); @@ -1078,26 +1071,20 @@ PG_FUNCTION_INFO_V1(dblink_cancel_query); Datum dblink_cancel_query(PG_FUNCTION_ARGS) { - char *msg; int res = 0; PGconn *conn = NULL; - char *conname = NULL; - char *connstr = NULL; remoteConn *rconn = NULL; - bool freeconn = false; PGcancel *cancel; char errbuf[256]; DBLINK_INIT; - DBLINK_GET_CONN; - if (!conn) - DBLINK_CONN_NOT_AVAIL; + DBLINK_GET_NAMED_CONN; cancel = PQgetCancel(conn); res = PQcancel(cancel, errbuf, 256); PQfreeCancel(cancel); - if (res == 0) + if (res == 1) PG_RETURN_TEXT_P(GET_TEXT("OK")); else PG_RETURN_TEXT_P(GET_TEXT(errbuf)); @@ -1120,18 +1107,13 @@ dblink_error_message(PG_FUNCTION_ARGS) { char *msg; PGconn *conn = NULL; - char *conname = NULL; - char *connstr = NULL; remoteConn *rconn = NULL; - bool freeconn = false; DBLINK_INIT; - DBLINK_GET_CONN; - if (!conn) - DBLINK_CONN_NOT_AVAIL; + DBLINK_GET_NAMED_CONN; msg = PQerrorMessage(conn); - if (!msg) + if (msg == NULL || msg[0] == '\0') PG_RETURN_TEXT_P(GET_TEXT("OK")); else PG_RETURN_TEXT_P(GET_TEXT(msg)); @@ -2299,3 +2281,23 @@ deleteConnection(const char *name) errmsg("undefined connection name"))); } + +static void +dblink_security_check(PGconn *conn, remoteConn *rconn) +{ + if (!superuser()) + { + if (!PQconnectionUsedPassword(conn)) + { + PQfinish(conn); + if (rconn) + pfree(rconn); + + ereport(ERROR, + (errcode(ERRCODE_S_R_E_PROHIBITED_SQL_STATEMENT_ATTEMPTED), + errmsg("password is required"), + errdetail("Non-superuser cannot connect if the server does not request a password."), + errhint("Target server's authentication method must be changed."))); + } + } +} diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out index bdd2f9926f..fd35d76af9 100644 --- a/contrib/dblink/expected/dblink.out +++ b/contrib/dblink/expected/dblink.out @@ -724,6 +724,12 @@ SELECT dblink_get_connections(); {dtest1,dtest2,dtest3} (1 row) +SELECT dblink_is_busy('dtest1'); + dblink_is_busy +---------------- + 0 +(1 row) + SELECT dblink_disconnect('dtest1'); dblink_disconnect ------------------- @@ -758,3 +764,34 @@ SELECT * from result; 10 | k | {a10,b10,c10} (11 rows) +SELECT dblink_connect('dtest1', 'dbname=contrib_regression'); + dblink_connect +---------------- + OK +(1 row) + +SELECT * from + dblink_send_query('dtest1', 'select * from foo where f1 < 3') as t1; + t1 +---- + 1 +(1 row) + +SELECT dblink_cancel_query('dtest1'); + dblink_cancel_query +--------------------- + OK +(1 row) + +SELECT dblink_error_message('dtest1'); + dblink_error_message +---------------------- + OK +(1 row) + +SELECT dblink_disconnect('dtest1'); + dblink_disconnect +------------------- + OK +(1 row) + diff --git a/contrib/dblink/sql/dblink.sql b/contrib/dblink/sql/dblink.sql index 277500e6f1..48e1daca54 100644 --- a/contrib/dblink/sql/dblink.sql +++ b/contrib/dblink/sql/dblink.sql @@ -344,9 +344,18 @@ UNION ORDER by f1; SELECT dblink_get_connections(); +SELECT dblink_is_busy('dtest1'); SELECT dblink_disconnect('dtest1'); SELECT dblink_disconnect('dtest2'); SELECT dblink_disconnect('dtest3'); + SELECT * from result; +SELECT dblink_connect('dtest1', 'dbname=contrib_regression'); +SELECT * from + dblink_send_query('dtest1', 'select * from foo where f1 < 3') as t1; + +SELECT dblink_cancel_query('dtest1'); +SELECT dblink_error_message('dtest1'); +SELECT dblink_disconnect('dtest1');