On 2023-01-09 Mo 13:24, Nathan Bossart wrote:
> On Mon, Jan 09, 2023 at 08:00:26AM -0500, Andrew Dunstan wrote:
>> + If the <replaceable>database-username</replaceable> begins with a
>> + <literal>+</literal> character, then the operating system user can login
>> as
>> + any user belonging to that role, similarly to how user names beginning
>> with
>> + <literal>+</literal> are treated in <literal>pg_hba.conf</literal>.
> I would Ñ•uggest making it clear that this means role membership and not
> privileges via INHERIT.
I've adapted a sentence from the pg_hba.conf documentation so we stay
consistent.
>> - if (case_insensitive)
>> + if (regexp_pgrole[0] == '+')
>> + {
>> + Oid roleid = get_role_oid(pg_role, true);
>> + if (is_member(roleid, regexp_pgrole +1))
>> + *found_p = true;
>> + }
>> + else if (case_insensitive)
> It looks like the is_member() check will always be case-sensitive. Should
> it respect the value of case_insensitive? If not, I think there should be
> a brief comment explaining why.
It's not really relevant. We're not comparing role names here; rather we
look up two roles and then ask if one is a member of the other. I've
added a comment.
Thanks for the review (I take it you're generally in favor).
cheers
andrew
--
Andrew Dunstan
EDB: https://www.enterprisedb.com
diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index cc8c59206c..a1c9a2eefc 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -961,6 +961,15 @@ mymap /^(.*)@otherdomain\.com$ guest
<literal>@mydomain.com</literal>, and allow any user whose system name ends with
<literal>@otherdomain.com</literal> to log in as <literal>guest</literal>.
</para>
+ <para>
+ If the <replaceable>database-username</replaceable> begins with a
+ <literal>+</literal> character, then the operating system user can login as
+ any user belonging to that role, similarly to how user names beginning with
+ <literal>+</literal> are treated in <literal>pg_hba.conf</literal>.
+ Thus, a <literal>+</literal> mark means <quote>match any of the roles that
+ are directly or indirectly members of this role</quote>, while a name
+ without a <literal>+</literal> mark matches only that specific role.
+ </para>
<tip>
<para>
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index f5a2cc53be..2d186639b1 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -2900,9 +2900,20 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name,
/*
* now check if the username actually matched what the user is trying
- * to connect as
+ * to connect as. First check if it's a member of a specified group
+ * role.
*/
- if (case_insensitive)
+ if (regexp_pgrole[0] == '+')
+ {
+ /*
+ * Since we're not comparing role names here, use of case
+ * insensitive matching doesn't really apply.
+ */
+ Oid roleid = get_role_oid(pg_role, true);
+ if (is_member(roleid, regexp_pgrole +1))
+ *found_p = true;
+ }
+ else if (case_insensitive)
{
if (pg_strcasecmp(regexp_pgrole, pg_role) == 0)
*found_p = true;
@@ -2919,16 +2930,29 @@ check_ident_usermap(IdentLine *identLine, const char *usermap_name,
else
{
/* Not regular expression, so make complete match */
- if (case_insensitive)
+
+ char *map_role = identLine->pg_role;
+
+ if (case_insensitive ?
+ (pg_strcasecmp(identLine->token->string, ident_user) != 0) :
+ (strcmp(identLine->token->string, ident_user) != 0))
+ return;
+
+ if (map_role[0] == '+')
{
- if (pg_strcasecmp(identLine->pg_role, pg_role) == 0 &&
- pg_strcasecmp(identLine->token->string, ident_user) == 0)
+ /* see comment above re case insensitive matching in this case */
+ Oid roleid = get_role_oid(pg_role, true);
+ if (is_member(roleid, ++map_role))
+ *found_p = true;
+ }
+ else if (case_insensitive)
+ {
+ if (pg_strcasecmp(map_role, pg_role) == 0)
*found_p = true;
}
else
{
- if (strcmp(identLine->pg_role, pg_role) == 0 &&
- strcmp(identLine->token->string, ident_user) == 0)
+ if (strcmp(map_role, pg_role) == 0)
*found_p = true;
}
}
diff --git a/src/test/authentication/t/003_peer.pl b/src/test/authentication/t/003_peer.pl
index 24cefd14e0..93ef2b8f68 100644
--- a/src/test/authentication/t/003_peer.pl
+++ b/src/test/authentication/t/003_peer.pl
@@ -100,6 +100,8 @@ if (find_in_log(
# Add a database role, to use for the user name map.
$node->safe_psql('postgres', qq{CREATE ROLE testmapuser LOGIN});
+$node->safe_psql('postgres',"CREATE ROLE testmapgroup NOLOGIN");
+$node->safe_psql('postgres', "GRANT testmapgroup TO testmapuser");
# Extract as well the system user for the user name map.
my $system_user =
@@ -142,17 +144,59 @@ test_role(
# Concatenate system_user to system_user.
-$regex_test_string = $system_user . $system_user;
+my $bad_regex_test_string = $system_user . $system_user;
# Failure as the regular expression does not match.
-reset_pg_ident($node, 'mypeermap', qq{/^.*$regex_test_string\$},
+reset_pg_ident($node, 'mypeermap', qq{/^.*$bad_regex_test_string\$},
'testmapuser');
test_role(
$node,
qq{testmapuser},
'peer',
2,
- 'with regular expression in user name map',
+ 'with bad regular expression in user name map',
log_like => [qr/no match in usermap "mypeermap" for user "testmapuser"/]);
+# test using a group role match
+# first with a plain user ...
+reset_pg_ident($node, 'mypeermap', $system_user, '+testmapgroup');
+test_role(
+ $node,
+ qq{testmapuser},
+ 'peer',
+ 0,
+ 'plain user with group',
+ log_like =>
+ [qr/connection authenticated: identity="$system_user" method=peer/]);
+
+test_role(
+ $node,
+ qq{testmapgroup},
+ 'peer',
+ 2,
+ 'group user with group',
+ log_like =>
+ [qr/role "testmapgroup" is not permitted to log in/]);
+
+# ... then with a regex user
+reset_pg_ident($node, 'mypeermap', qq{/^.*$regex_test_string\$}, '+testmapgroup');
+
+test_role(
+ $node,
+ qq{testmapuser},
+ 'peer',
+ 0,
+ 'regex user with group',
+ log_like =>
+ [qr/connection authenticated: identity="$system_user" method=peer/]);
+
+test_role(
+ $node,
+ qq{testmapgroup},
+ 'peer',
+ 2,
+ 'regex group user with group',
+ log_like =>
+ [qr/role "testmapgroup" is not permitted to log in/]);
+
done_testing();
