min_password_length_v4.patch

diff --git a/contrib/passwordcheck/expected/passwordcheck.out b/contrib/passwordcheck/expected/passwordcheck.out
index 2027681daf..8f1f0baaab 100644
--- a/contrib/passwordcheck/expected/passwordcheck.out
+++ b/contrib/passwordcheck/expected/passwordcheck.out
@@ -1,9 +1,10 @@
 LOAD 'passwordcheck';
+SET passwordcheck.min_password_length = 12;
 CREATE USER regress_passwordcheck_user1;
 -- ok
 ALTER USER regress_passwordcheck_user1 PASSWORD 'a_nice_long_password';
 -- error: too short
-ALTER USER regress_passwordcheck_user1 PASSWORD 'tooshrt';
+ALTER USER regress_passwordcheck_user1 PASSWORD 'tooshort';
 ERROR:  password is too short
 -- error: contains user name
 ALTER USER regress_passwordcheck_user1 PASSWORD 'xyzregress_passwordcheck_user1';
diff --git a/contrib/passwordcheck/passwordcheck.c b/contrib/passwordcheck/passwordcheck.c
index 0785618f2a..67ad8aee1f 100644
--- a/contrib/passwordcheck/passwordcheck.c
+++ b/contrib/passwordcheck/passwordcheck.c
@@ -6,6 +6,8 @@
  * Copyright (c) 2009-2024, PostgreSQL Global Development Group
  *
  * Author: Laurenz Albe <laurenz.albe@wien.gv.at>
+ * Author: Maurizio Boriani <maurizio@boriani.cloud>
+ * Author: Emanuele Musella <emamuse86@gmail.com>
  *
  * IDENTIFICATION
  *	  contrib/passwordcheck/passwordcheck.c
@@ -23,14 +25,16 @@
 #include "commands/user.h"
 #include "fmgr.h"
 #include "libpq/crypt.h"
+#include "commands/explain.h"
+#include "utils/guc.h"
 
 PG_MODULE_MAGIC;
 
 /* Saved hook value in case of unload */
 static check_password_hook_type prev_check_password_hook = NULL;
 
-/* passwords shorter than this will be rejected */
-#define MIN_PWD_LENGTH 8
+/* min_password_length minimum password length */
+int min_password_length;
 
 /*
  * check_password
@@ -93,7 +97,7 @@ check_password(const char *username,
 #endif
 
 		/* enforce minimum length */
-		if (pwdlen < MIN_PWD_LENGTH)
+		if (pwdlen < min_password_length)
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 					 errmsg("password is too short")));
@@ -145,4 +149,17 @@ _PG_init(void)
 	/* activate password checks when the module is loaded */
 	prev_check_password_hook = check_password_hook;
 	check_password_hook = check_password;
+
+	/* Define custom GUC variables. */
+	DefineCustomIntVariable("passwordcheck.min_password_length",
+				"Sets the minimum allowed password length.",
+				"8 is default.",
+				&min_password_length,
+				8,
+				0, INT_MAX,
+				PGC_SUSET,
+				GUC_UNIT_MS,
+				NULL,
+				NULL,
+				NULL);
 }
diff --git a/contrib/passwordcheck/sql/passwordcheck.sql b/contrib/passwordcheck/sql/passwordcheck.sql
index 1fbd6b0e96..c151685c74 100644
--- a/contrib/passwordcheck/sql/passwordcheck.sql
+++ b/contrib/passwordcheck/sql/passwordcheck.sql
@@ -1,12 +1,12 @@
 LOAD 'passwordcheck';
-
+SET passwordcheck.min_password_length = 12;
 CREATE USER regress_passwordcheck_user1;
 
 -- ok
 ALTER USER regress_passwordcheck_user1 PASSWORD 'a_nice_long_password';
 
 -- error: too short
-ALTER USER regress_passwordcheck_user1 PASSWORD 'tooshrt';
+ALTER USER regress_passwordcheck_user1 PASSWORD 'tooshort';
 
 -- error: contains user name
 ALTER USER regress_passwordcheck_user1 PASSWORD 'xyzregress_passwordcheck_user1';
diff --git a/doc/src/sgml/passwordcheck.sgml b/doc/src/sgml/passwordcheck.sgml
index 601f489227..e56323cdc9 100644
--- a/doc/src/sgml/passwordcheck.sgml
+++ b/doc/src/sgml/passwordcheck.sgml
@@ -22,6 +22,12 @@
   <filename>postgresql.conf</filename>, then restart the server.
  </para>
 
+ <para>
+  In <filename>postgresql.conf</filename> you may set the minimum password length
+  by setting passwordcheck.min_password_length = INT.
+  The default minimum password length if not setted passwordcheck.min_password_length is 8 chars.
+ </para>
+
  <para>
   You can adapt this module to your needs by changing the source code.
   For example, you can use