Extend the functionality offered by the -o option into a new option

-O, which limits the impact of the write-only restriction to guest
users.

*) The existing manual page's SYNOPSIS and option listing in the
   DESCRIPTION are already horribly disordered.  No attempt has been
   made to fix this.

*) The existing source's getopt() optstring and option handling switch
   are already horribly disordered.  No attempt has been made to fix
   this.

Discussed with: nik, -audit

3 files changed, 15 insertions, 2 deletions

diff --git a/libexec/ftpd/ftpcmd.y b/libexec/ftpd/ftpcmd.y
index 2da3ef2..381d87c 100644
--- a/libexec/ftpd/ftpcmd.y
+++ b/libexec/ftpd/ftpcmd.y
@@ -94,6 +94,7 @@ extern  char tmpline[];
 extern	int readonly;
 extern	int noepsv;
 extern	int noretr;
+extern	int noguestretr;
 
 off_t	restart_point;
 
@@ -440,7 +441,7 @@ cmd
 		}
 	| RETR check_login SP pathname CRLF
 		{
-			if (noretr)
+			if (noretr || (guest && noguestretr))
 				reply(500, "RETR command is disabled");
 			else if ($2 && $4 != NULL)
 				retrieve((char *) 0, $4);
diff --git a/libexec/ftpd/ftpd.8 b/libexec/ftpd/ftpd.8
index 1b64380..157403c 100644
--- a/libexec/ftpd/ftpd.8
+++ b/libexec/ftpd/ftpd.8
@@ -51,6 +51,7 @@
 .Op Fl U
 .Op Fl r
 .Op Fl o
+.Op Fl O
 .Op Fl E
 .Op Fl T Ar maxtimeout
 .Op Fl t Ar timeout
@@ -161,6 +162,12 @@ All commands which may modify the local filesystem are disabled.
 .It Fl o
 Put server in write-only mode.
 RETR is disabled, preventing downloads.
+.It Fl O
+Put server in write-only mode for anonymous users only.
+RETR is disabled for anonymous users, preventing anonymous downloads.
+This has no effect if
+.Fl o
+is also specified.
 .It Fl E
 Disable the EPSV command.
 This is useful for servers behind older firewalls.
diff --git a/libexec/ftpd/ftpd.c b/libexec/ftpd/ftpd.c
index 93f0a90..e3e0748 100644
--- a/libexec/ftpd/ftpd.c
+++ b/libexec/ftpd/ftpd.c
@@ -150,6 +150,7 @@ int	pdata = -1;		/* for passive mode */
 int	readonly=0;		/* Server is in readonly mode.	*/
 int	noepsv=0;		/* EPSV command is disabled.	*/
 int	noretr=0;		/* RETR command is disabled.	*/
+int	noguestretr=0;		/* RETR command is disabled for anon users. */
 
 sig_atomic_t transflag;
 off_t	file_size;
@@ -301,7 +302,7 @@ main(argc, argv, envp)
 #endif /* OLD_SETPROCTITLE */
 
 
-	while ((ch = getopt(argc, argv, "AdlDESURrt:T:u:voa:p:46")) != -1) {
+	while ((ch = getopt(argc, argv, "AdlDESURrt:T:u:vOoa:p:46")) != -1) {
 		switch (ch) {
 		case 'D':
 			daemon_mode++;
@@ -384,6 +385,10 @@ main(argc, argv, envp)
 			family = AF_INET6;
 			break;
 
+		case 'O':
+			noguestretr = 1;
+			break;
+
 		case 'o':
 			noretr = 1;
 			break;