tftp: optional tftp-hpa compat

function                                             old     new   delta
tftp_main                                            276     394    +118

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 43 insertions, 3 deletions

diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index ea5fe173f..eb2871cb1 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -133,6 +133,7 @@ unsigned FAST_FUNC bb_lookup_port(const char *port, const char *protocol, unsign
 			port_nr = default_port;
 			if (tserv)
 				port_nr = ntohs(tserv->s_port);
+//FIXME: else: port string was garbage, but we don't report that???
 		}
 		errno = old_errno;
 	}
diff --git a/networking/tftp.c b/networking/tftp.c
index 5ebd22105..30232ef8e 100644
--- a/networking/tftp.c
+++ b/networking/tftp.c
@@ -31,6 +31,11 @@
 //config:	default y
 //config:	depends on TFTP
 //config:
+//config:config FEATURE_TFTP_HPA_COMPAT
+//config:	bool "tftp-hpa compat (support -c get/put FILE)"
+//config:	default y
+//config:	depends on TFTP
+//config:
 //config:config TFTPD
 //config:	bool "tftpd (10 kb)"
 //config:	default y
@@ -101,9 +106,10 @@
 //usage:	IF_FEATURE_TFTP_BLOCKSIZE(
 //usage:     "\n	-b SIZE	Transfer blocks of SIZE octets"
 //usage:	)
+///////:     "\n	-m STR	Accepted and ignored ('-m binary' compat with tftp-hpa 5.2)"
 //usage:
 //usage:#define tftpd_trivial_usage
-//usage:       "[-cr] [-u USER] [DIR]"
+//usage:       "[-crl] [-u USER] [DIR]"
 //usage:#define tftpd_full_usage "\n\n"
 //usage:       "Transfer a file on tftp client's request\n"
 //usage:       "\n"
@@ -759,15 +765,46 @@ int tftp_main(int argc UNUSED_PARAM, char **argv)
 
 	INIT_G();
 
+	if (ENABLE_FEATURE_TFTP_HPA_COMPAT) {
+		/* As of 2019, common tftp client in Linux distros
+		 * is one maintained by H. Peter Anvin:
+		 * I've seen "tftp-hpa 5.2" version.
+		 * Make the following command work:
+		 *  "tftp HOST [PORT] -m binary -c get/put FILE"
+		 * by mangling it into "....... -g/-p -r FILE"
+		 * and accepting and ignoring -m STR option.
+		 */
+		unsigned i = 1;
+		while (argv[i]) {
+			if (strcmp(argv[i], "-c") == 0) {
+				if (!argv[++i])
+					break;
+				if (strcmp(argv[i], "get") == 0) {
+					argv[i-1] = (char*)"-g";
+					argv[i] = (char*)"-r";
+					break;
+				}
+				if (strcmp(argv[i], "put") == 0) {
+					argv[i-1] = (char*)"-p";
+					argv[i] = (char*)"-r";
+					break;
+				}
+			}
+			i++;
+		}
+	}
+
 	IF_GETPUT(opt =) getopt32(argv, "^"
 			IF_FEATURE_TFTP_GET("g") IF_FEATURE_TFTP_PUT("p")
 			"l:r:" IF_FEATURE_TFTP_BLOCKSIZE("b:")
+			IF_FEATURE_TFTP_HPA_COMPAT("m:")
 			"\0"
 			/* -p or -g is mandatory, and they are mutually exclusive */
 			IF_FEATURE_TFTP_GET("g:") IF_FEATURE_TFTP_PUT("p:")
 			IF_GETPUT("g--p:p--g:"),
 			&local_file, &remote_file
 			IF_FEATURE_TFTP_BLOCKSIZE(, &blksize_str)
+			IF_FEATURE_TFTP_HPA_COMPAT(, NULL)
 	);
 	argv += optind;
 
@@ -851,7 +888,7 @@ int tftpd_main(int argc UNUSED_PARAM, char **argv)
 	peer_lsa->len = our_lsa->len;
 
 	/* Shifting to not collide with TFTP_OPTs */
-	opt = option_mask32 = TFTPD_OPT | (getopt32(argv, "rcu:l", &user_opt) << 8);
+	opt = option_mask32 = TFTPD_OPT | (getopt32(argv, "rcu:lm:", &user_opt, NULL) << 8);
 	argv += optind;
 	if (opt & TFTPD_OPT_l) {
 		openlog(applet_name, LOG_PID, LOG_DAEMON);
@@ -897,6 +934,7 @@ int tftpd_main(int argc UNUSED_PARAM, char **argv)
 	mode = local_file + strlen(local_file) + 1;
 	/* RFC 1350 says mode string is case independent */
 	if (mode >= G.block_buf + result || strcasecmp(mode, "octet") != 0) {
+		error_msg = "mode is not 'octet'";
 		goto err;
 	}
 # if ENABLE_FEATURE_TFTP_BLOCKSIZE
@@ -944,7 +982,8 @@ int tftpd_main(int argc UNUSED_PARAM, char **argv)
 	/* tftp_protocol() will create new one, bound to particular local IP */
 	result = tftp_protocol(
 		our_lsa, peer_lsa,
-		local_file IF_TFTP(, NULL /*remote_file*/)
+		local_file
+		IF_TFTP(, NULL /*remote_file*/)
 		IF_FEATURE_TFTP_BLOCKSIZE(, want_transfer_size)
 		IF_FEATURE_TFTP_BLOCKSIZE(, blksize)
 	);