Patch for popa3d-0.5.9 enabling `user mode' -- when server is started in
inetd (i.e. non-standalone) mode with non-zero UID, it will not do
anything that requires root priviledges, omit any authentication (accept
anything for USER and PASS) and work on current user's own mailbox.  It
lets user start pop3 sessions from other programs that he can run with
his UID without needing to give them his password (e.g. start popa3d
via SSH (like with `plugin' option of fetchmail), thus securing his
POP3 sessions)

Hope it will function well and be useful.

		--Maciek Pasternacki <maciekp@japhy.fnord.org>

diff -b -u -r -U 5 popa3d-0.5.9-vanilla/params.h popa3d-0.5.9-jph/params.h
--- popa3d-0.5.9-vanilla/params.h	2002-09-08 11:49:24.000000000 +0200
+++ popa3d-0.5.9-jph/params.h	2003-01-04 02:43:16.000000000 +0100
@@ -122,10 +122,18 @@
  * work without it.
  */
 #define POP_SUPPORT_LAST		1
 
 /*
+ * Should the server enable user mode (without chroot, authentication
+ * etc) when invoked with nonzero UID, thus letting user start pop3
+ * session as SSH command without having to specify the password
+ * twice?
+ */
+#define ENABLE_USER_MODE                0
+
+/*
  * Introduce some sane limits on the mailbox size in order to prevent
  * a single huge mailbox from stopping the entire POP service.
  */
 #define MAX_MAILBOX_MESSAGES		200000
 #define MAX_MAILBOX_OPEN_BYTES		200000000
diff -b -u -r -U 5 popa3d-0.5.9-vanilla/pop_root.c popa3d-0.5.9-jph/pop_root.c
--- popa3d-0.5.9-vanilla/pop_root.c	2002-03-21 21:15:19.000000000 +0100
+++ popa3d-0.5.9-jph/pop_root.c	2003-01-04 02:41:32.000000000 +0100
@@ -42,10 +42,14 @@
 
 static int known;
 static char *user;
 static char *spool, *mailbox;
 
+#if ENABLE_USER_MODE
+static int user_mode = 0;
+#endif
+
 int log_error(char *s)
 {
 	syslog(SYSLOG_PRI_ERROR, "%s: %m", s);
 	return 1;
 }
@@ -67,10 +71,15 @@
 static int drop_root(void)
 {
 	tzset();
 	openlog(SYSLOG_IDENT, SYSLOG_OPTIONS | LOG_NDELAY, SYSLOG_FACILITY);
 
+#if ENABLE_USER_MODE
+        if ( user_mode )
+             return 0;
+#endif
+
 	if (chroot(POP_CHROOT)) return log_error("chroot");
 	if (chdir("/")) return log_error("chdir");
 
 	return set_user(&pop_pw);
 }
@@ -129,10 +138,17 @@
 
 	user = auth;
 	pass = &user[strlen(user) + 1];
 
 	pw = NULL;
+
+#if ENABLE_USER_MODE
+        if ( user_mode ) {
+             pw = getpwuid(getuid());
+        } else {
+#endif /* ENABLE_USER_MODE */
+
 #if POP_VIRTUAL
 	if (!(pw = virtual_userpass(user, pass, &known)) && virtual_domain) {
 		memset(pass, 0, strlen(pass));
 		return AUTH_FAILED;
 	}
@@ -169,10 +185,14 @@
 
 #if VIRTUAL_ONLY
 	/* never reached */
 	return AUTH_FAILED;
 #else
+#if ENABLE_USER_MODE
+        }
+#endif
+
 #ifdef MAIL_SPOOL_PATH
 	spool = MAIL_SPOOL_PATH;
 	mailbox = user;
 #else
 	spool = pw->pw_dir;
@@ -185,10 +205,16 @@
 
 int do_pop_startup(void)
 {
 	struct passwd *pw;
 
+#if ENABLE_USER_MODE
+        user_mode = ( getuid() != 0 );
+        if ( user_mode )
+             return 0;
+#endif /* ENABLE_USER_MODE */
+
 	umask(077);
 	signal(SIGPIPE, SIG_IGN);
 
 	openlog(SYSLOG_IDENT, SYSLOG_OPTIONS, SYSLOG_FACILITY);