[BusyBox] [PATCH] udhcpc --userclass option

[Patrick J. LoPresti]

When using udhcpc on a boot disk, it is sometimes useful for the DHCP
server to know that the boot disk is in use.  In particular, it would
be handy to be able to set the "user class identifier" as specified by
RFC 3004.

The attached patch adds a "--userclass=..." option to udhcpc.  I
tested it by using Ethereal to sniff the traffic, and it looks good.

Strictly speaking, multiple "--userclass=..." options should be
permitted.  My patch does not implement this; it only handles a single
user class identifier.  If this could make the difference between
accepting my patch and ignoring it, let me know and I will take
another crack at it.

Cheers!

 - Pat

-------------- next part --------------
diff -u -r busybox-1.00-pre10/networking/udhcp.orig/clientpacket.c busybox-1.00-pre10/networking/udhcp/clientpacket.c
--- busybox-1.00-pre10/networking/udhcp.orig/clientpacket.c	2004-03-15 03:29:00.000000000 -0500
+++ busybox-1.00-pre10/networking/udhcp/clientpacket.c	2004-05-17 15:16:42.000000000 -0400
@@ -78,6 +78,7 @@
 	memcpy(packet->chaddr, client_config.arp, 6);
 	add_option_string(packet->options, client_config.clientid);
 	if (client_config.hostname) add_option_string(packet->options, client_config.hostname);
+	if (client_config.userclass) add_option_string(packet->options, client_config.userclass);
 	add_option_string(packet->options, (uint8_t *) &vendor_id);
 }
 
diff -u -r busybox-1.00-pre10/networking/udhcp.orig/dhcpc.c busybox-1.00-pre10/networking/udhcp/dhcpc.c
--- busybox-1.00-pre10/networking/udhcp.orig/dhcpc.c	2004-03-15 03:29:00.000000000 -0500
+++ busybox-1.00-pre10/networking/udhcp/dhcpc.c	2004-05-17 15:41:43.000000000 -0400
@@ -67,6 +67,7 @@
 	script: DEFAULT_SCRIPT,
 	clientid: NULL,
 	hostname: NULL,
+        userclass: NULL,
 	ifindex: 0,
 	arp: "\0\0\0\0\0\0",		/* appease gcc-3.0 */
 };
@@ -90,6 +91,7 @@
 "  -r, --request=IP                IP address to request (default: none)\n"
 "  -s, --script=file               Run file at dhcp events (default:\n"
 "                                  " DEFAULT_SCRIPT ")\n"
+"  -u, --userclass=USERCLASS       User class identifier (RFC 3004)\n"
 "  -v, --version                   Display version\n"
 	);
 	exit(0);
@@ -204,6 +206,7 @@
 		{"quit",	no_argument,		0, 'q'},
 		{"request",	required_argument,	0, 'r'},
 		{"script",	required_argument,	0, 's'},
+                {"userclass",   required_argument,      0, 'u'},
 		{"version",	no_argument,		0, 'v'},
 		{0, 0, 0, 0}
 	};
@@ -211,7 +214,7 @@
 	/* get options */
 	while (1) {
 		int option_index = 0;
-		c = getopt_long(argc, argv, "c:fbH:h:i:np:qr:s:v", arg_options, &option_index);
+		c = getopt_long(argc, argv, "c:fbH:h:i:np:qr:s:u:v", arg_options, &option_index);
 		if (c == -1) break;
 
 		switch (c) {
@@ -257,6 +260,16 @@
 		case 's':
 			client_config.script = optarg;
 			break;
+		case 'u':
+			len = strlen(optarg) > 255 ? 255 : strlen(optarg);
+			if (client_config.userclass) free(client_config.userclass);
+			client_config.userclass = xmalloc(len + OPT_DATA + 1);
+			client_config.userclass[OPT_CODE] = DHCP_USER_CLASS;
+			client_config.userclass[OPT_LEN] = len+1;
+                        client_config.userclass[OPT_DATA] = len;
+			strncpy(client_config.userclass + OPT_DATA + 1,
+                                optarg, len);
+			break;
 		case 'v':
 			printf("udhcpcd, version %s\n\n", VERSION);
 			return 0;
diff -u -r busybox-1.00-pre10/networking/udhcp.orig/dhcpc.h busybox-1.00-pre10/networking/udhcp/dhcpc.h
--- busybox-1.00-pre10/networking/udhcp.orig/dhcpc.h	2004-01-30 18:45:12.000000000 -0500
+++ busybox-1.00-pre10/networking/udhcp/dhcpc.h	2004-05-17 15:16:14.000000000 -0400
@@ -27,6 +27,7 @@
 	char *script;			/* User script to run at dhcp events */
 	uint8_t *clientid;		/* Optional client id to use */
 	uint8_t *hostname;		/* Optional hostname to use */
+        uint8_t *userclass;             /* Optional user class id to use */
 	int ifindex;			/* Index number of the interface to use */
 	uint8_t arp[6];			/* Our arp address */
 };
diff -u -r busybox-1.00-pre10/networking/udhcp.orig/dhcpd.h busybox-1.00-pre10/networking/udhcp/dhcpd.h
--- busybox-1.00-pre10/networking/udhcp.orig/dhcpd.h	2004-03-15 03:29:00.000000000 -0500
+++ busybox-1.00-pre10/networking/udhcp/dhcpd.h	2004-05-17 15:13:35.000000000 -0400
@@ -63,6 +63,7 @@
 #define DHCP_T2			0x3b
 #define DHCP_VENDOR		0x3c
 #define DHCP_CLIENT_ID		0x3d
+#define DHCP_USER_CLASS         0x4d
 
 #define DHCP_END		0xFF