[git commit master] ftpd: conditional support for broken clients

[Denys Vlasenko]

commit: http://git.busybox.net/busybox/commit/?id=f3fc9ac166d2413d331e3189a132a693608695ba
branch: http://git.busybox.net/busybox/commit/?id=refs/heads/master

Signed-off-by: Stefan Seyfried <stefan.seyfried at googlemail.com>
Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 networking/Config.in |   11 +++++++++++
 networking/ftpd.c    |   12 ++++++++++++
 2 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/networking/Config.in b/networking/Config.in
index 80834c6..788e128 100644
--- a/networking/Config.in
+++ b/networking/Config.in
@@ -117,6 +117,17 @@ config FEATURE_FTP_WRITE
 	help
 	  Enable all kinds of FTP upload commands (-w option)
 
+config FEATURE_FTPD_ACCEPT_BROKEN_LIST
+	bool "Enable workaround for RFC-violating clients"
+	default y
+	depends on FTPD
+	help
+	  Some ftp-clients (among them KDE's Konqueror) issue illegal
+	  "LIST -la" requests. This option works around those problems.
+	  It might prevent you from listing files starting with "-" and
+	  it increases the code size by ~40 bytes.
+	  Most other ftp servers seem to behave similar to this.
+
 config FTPGET
 	bool "ftpget"
 	default n
diff --git a/networking/ftpd.c b/networking/ftpd.c
index 4e9f65c..fdc6f5e 100644
--- a/networking/ftpd.c
+++ b/networking/ftpd.c
@@ -632,6 +632,18 @@ popen_ls(const char *opt)
 	argv[3] = G.ftp_arg;
 	argv[4] = NULL;
 
+	/* Improve compatibility with non-RFC conforming FTP clients
+	 * which send e.g. "LIST -l", "LIST -la".
+	 * See https://bugs.kde.org/show_bug.cgi?id=195578 */
+	if (ENABLE_FEATURE_FTPD_ACCEPT_BROKEN_LIST
+	 && G.ftp_arg && G.ftp_arg[0] == '-' && G.ftp_arg[1] == 'l'
+	) {
+		const char *tmp = strchr(G.ftp_arg, ' ');
+		if (tmp) /* skip the space */
+			tmp++;
+		argv[3] = tmp;
+	}
+
 	xpiped_pair(outfd);
 
 	/*fflush_all(); - so far we dont use stdio on output */
-- 
1.6.3.3