From 00c5f55061df52ccfd82eae16f054e08818ad0ff Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Sat, 14 Jan 2012 18:22:16 +0200 Subject: [PATCH] Make superuser imply replication privilege. The idea of a privilege that superuser doesn't have doesn't make much sense, as a superuser can do whatever he wants through other means, anyway. So instead of granting replication privilege to superusers in CREATE USER time by default, allow replication connection from superusers whether or not they have the replication privilege. Patch by Noah Misch, per discussion on bug report #6264 --- doc/src/sgml/high-availability.sgml | 21 ++++++--------------- doc/src/sgml/recovery-config.sgml | 5 ++--- doc/src/sgml/ref/create_role.sgml | 3 +-- doc/src/sgml/ref/pg_basebackup.sgml | 13 +++++++------ doc/src/sgml/ref/pg_receivexlog.sgml | 14 +++++++------- doc/src/sgml/user-manag.sgml | 18 +++++++----------- src/backend/commands/user.c | 9 --------- src/backend/utils/init/postinit.c | 5 ++--- 8 files changed, 32 insertions(+), 56 deletions(-) diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml index 86c2729cfd..c5db6ef01f 100644 --- a/doc/src/sgml/high-availability.sgml +++ b/doc/src/sgml/high-availability.sgml @@ -797,23 +797,14 @@ archive_cleanup_command = 'pg_archivecleanup /path/to/archive %r' It is very important that the access privileges for replication be set up so that only trusted users can read the WAL stream, because it is easy to extract privileged information from it. Standby servers must - authenticate to the primary as an account that has the - REPLICATION privilege. So a role with the - REPLICATION and LOGIN privileges needs to be - created on the primary. + authenticate to the primary as a superuser or an account that has the + REPLICATION privilege. It is recommended to create a + dedicated user account with REPLICATION and LOGIN + privileges for replication. While REPLICATION privilege gives + very high permissions, it does not allow the user to modify any data on + the primary system, which the SUPERUSER privilege does. - - - It is recommended that a dedicated user account is used for replication. - While the REPLICATION privilege is granted to superuser - accounts by default, it is not recommended to use superuser accounts - for replication. While REPLICATION privilege gives very high - permissions, it does not allow the user to modify any data on the - primary system, which the SUPERUSER privilege does. - - - Client authentication for replication is controlled by a pg_hba.conf record specifying replication in the diff --git a/doc/src/sgml/recovery-config.sgml b/doc/src/sgml/recovery-config.sgml index 86470242ea..7e39c0db75 100644 --- a/doc/src/sgml/recovery-config.sgml +++ b/doc/src/sgml/recovery-config.sgml @@ -325,9 +325,8 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows The connection string should specify the host name (or address) of the primary server, as well as the port number if it is not the same as the standby server's default. - Also specify a user name corresponding to a role that has the - REPLICATION and LOGIN privileges on the - primary (see + Also specify a user name corresponding to a suitably-privileged role + on the primary (see ). A password needs to be provided too, if the primary demands password authentication. It can be provided in the diff --git a/doc/src/sgml/ref/create_role.sgml b/doc/src/sgml/ref/create_role.sgml index 4953df678d..7ec4d0a8e4 100644 --- a/doc/src/sgml/ref/create_role.sgml +++ b/doc/src/sgml/ref/create_role.sgml @@ -185,8 +185,7 @@ CREATE ROLE name [ [ WITH ] REPLICATION attribute is a very highly privileged role, and should only be used on roles actually used for replication. If not specified, - NOREPLICATION is the default for all roles except - superusers. + NOREPLICATION is the default. diff --git a/doc/src/sgml/ref/pg_basebackup.sgml b/doc/src/sgml/ref/pg_basebackup.sgml index 8c8c78f0d1..05d5bedef9 100644 --- a/doc/src/sgml/ref/pg_basebackup.sgml +++ b/doc/src/sgml/ref/pg_basebackup.sgml @@ -50,12 +50,13 @@ PostgreSQL documentation The backup is made over a regular PostgreSQL - connection, and uses the replication protocol. The connection must be - made with a user having REPLICATION permissions (see - ), and the user must be granted explicit - permissions in pg_hba.conf. The server must also - be configured with set high enough - to leave at least one session available for the backup. + connection, and uses the replication protocol. The connection must be made + with a superuser or a user having REPLICATION + permissions (see ), + and pg_hba.conf must explicitly permit the replication + connection. The server must also be configured + with set high enough to leave at least + one session available for the backup. diff --git a/doc/src/sgml/ref/pg_receivexlog.sgml b/doc/src/sgml/ref/pg_receivexlog.sgml index 9a2a24ba2e..fad7470ee3 100644 --- a/doc/src/sgml/ref/pg_receivexlog.sgml +++ b/doc/src/sgml/ref/pg_receivexlog.sgml @@ -50,13 +50,13 @@ PostgreSQL documentation The transaction log is streamed over a regular - PostgreSQL connection, and uses the - replication protocol. The connection must be - made with a user having REPLICATION permissions (see - ), and the user must be granted explicit - permissions in pg_hba.conf. The server must also - be configured with set high enough - to leave at least one session available for the stream. + PostgreSQL connection, and uses the replication + protocol. The connection must be made with a superuser or a user + having REPLICATION permissions (see + ), and pg_hba.conf + must explicitly permit the replication connection. The server must also be + configured with set high enough to + leave at least one session available for the stream. diff --git a/doc/src/sgml/user-manag.sgml b/doc/src/sgml/user-manag.sgml index 0a4f82daae..177ac7aa8c 100644 --- a/doc/src/sgml/user-manag.sgml +++ b/doc/src/sgml/user-manag.sgml @@ -169,16 +169,11 @@ CREATE USER name; A database superuser bypasses all permission checks, except the right - to log in or the right to initiate replication. This is a - dangerous privilege and should not be used carelessly; it is best - to do most of your work as a role that is not a superuser. - To create a new database superuser, use CREATE ROLE - name SUPERUSER. You must do - this as a role that is already a superuser. Creating a superuser - will by default also grant permissions to initiate streaming - replication. For increased security this can be disallowed using - CREATE ROLE name SUPERUSER - NOREPLICATION. + to log in. This is a dangerous privilege and should not be used + carelessly; it is best to do most of your work as a role that is not a + superuser. To create a new database superuser, use CREATE + ROLE name SUPERUSER. You must do + this as a role that is already a superuser. @@ -217,7 +212,8 @@ CREATE USER name; A role must explicitly be given permission to initiate streaming - replication. A role used for streaming replication must always + replication (except for superusers, since those bypass all permission + checks). A role used for streaming replication must always have LOGIN permission as well. To create such a role, use CREATE ROLE name REPLICATION LOGIN. diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c index a90f0b1ffe..9a88c90789 100644 --- a/src/backend/commands/user.c +++ b/src/backend/commands/user.c @@ -239,16 +239,7 @@ CreateRole(CreateRoleStmt *stmt) if (dpassword && dpassword->arg) password = strVal(dpassword->arg); if (dissuper) - { issuper = intVal(dissuper->arg) != 0; - - /* - * Superusers get replication by default, but only if NOREPLICATION - * wasn't explicitly mentioned - */ - if (issuper && !(disreplication && intVal(disreplication->arg) == 0)) - isreplication = 1; - } if (dinherit) inherit = intVal(dinherit->arg) != 0; if (dcreaterole) diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c index f9e4dbc0c0..1baa67da9f 100644 --- a/src/backend/utils/init/postinit.c +++ b/src/backend/utils/init/postinit.c @@ -659,11 +659,10 @@ InitPostgres(const char *in_dbname, Oid dboid, const char *username, { Assert(!bootstrap); - /* must have authenticated as a replication role */ - if (!is_authenticated_user_replication_role()) + if (!superuser() && !is_authenticated_user_replication_role()) ereport(FATAL, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), - errmsg("must be replication role to start walsender"))); + errmsg("must be superuser or replication role to start walsender"))); /* process any options passed in the startup packet */ if (MyProcPort != NULL)