Rename cons_options() to pack_options(), and do_packet() to

unpack_options(). Store the unpacked options in a static
variable. Move remaining raw packet processing from unpack_options()
to packethandler().

No more struct interface_info knowledge in options.c

4 files changed, 96 insertions, 94 deletions

diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index ccbbe58425d..94659f6aa21 100644
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhclient.c,v 1.456 2017/07/06 16:56:52 krw Exp $	*/
+/*	$OpenBSD: dhclient.c,v 1.457 2017/07/07 14:53:06 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -1560,7 +1560,7 @@ make_discover(struct interface_info *ifi, struct client_lease *lease)
 	 * RFC 791 says is the largest packet that *MUST* be accepted
 	 * by any host.
 	 */
-	i = cons_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
+	i = pack_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
 	    options);
 	if (i == -1 || packet->options[i] != DHO_END)
 		fatalx("options do not fit in DHCPDISCOVER packet.");
@@ -1636,7 +1636,7 @@ make_request(struct interface_info *ifi, struct client_lease * lease)
 	 * RFC 791 says is the largest packet that *MUST* be accepted
 	 * by any host.
 	 */
-	i = cons_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
+	i = pack_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
 	    options);
 	if (i == -1 || packet->options[i] != DHO_END)
 		fatalx("options do not fit in DHCPREQUEST packet.");
@@ -1709,7 +1709,7 @@ make_decline(struct interface_info *ifi, struct client_lease *lease)
 	 * RFC 791 says is the largest packet that *MUST* be accepted
 	 * by any host.
 	 */
-	i = cons_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
+	i = pack_options(ifi->sent_packet.options, 576 - DHCP_FIXED_LEN,
 	    options);
 	if (i == -1 || packet->options[i] != DHO_END)
 		fatalx("options do not fit in DHCPDECLINE packet.");
diff --git a/sbin/dhclient/dhcpd.h b/sbin/dhclient/dhcpd.h
index 9ea01048b1e..5b3e7f7caa6 100644
--- a/sbin/dhclient/dhcpd.h
+++ b/sbin/dhclient/dhcpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhcpd.h,v 1.204 2017/07/06 16:56:52 krw Exp $	*/
+/*	$OpenBSD: dhcpd.h,v 1.205 2017/07/07 14:53:06 krw Exp $	*/
 
 /*
  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
@@ -170,13 +170,12 @@ extern struct in_addr deleting;
 extern struct in_addr adding;
 
 /* options.c */
-int cons_options(unsigned char *, int, struct option_data *);
+int pack_options(unsigned char *, int, struct option_data *);
 char *pretty_print_option(unsigned int, struct option_data *, int);
 char *pretty_print_domain_search(unsigned char *, size_t);
 char *pretty_print_string(unsigned char *, size_t, int);
 char *pretty_print_classless_routes(unsigned char *, size_t);
-void do_packet(struct interface_info *, unsigned int, struct in_addr,
-    struct ether_addr *);
+struct option_data *unpack_options(struct dhcp_packet *);
 
 /* conflex.c */
 extern int lexline, lexchar;
diff --git a/sbin/dhclient/dispatch.c b/sbin/dhclient/dispatch.c
index a9d4fc8aba0..b3afeff1e7c 100644
--- a/sbin/dhclient/dispatch.c
+++ b/sbin/dhclient/dispatch.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dispatch.c,v 1.131 2017/07/06 16:56:52 krw Exp $	*/
+/*	$OpenBSD: dispatch.c,v 1.132 2017/07/07 14:53:07 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -205,7 +205,12 @@ packethandler(struct interface_info *ifi)
 	struct in_addr		 ifrom;
 	struct dhcp_packet	*packet = &ifi->recv_packet;
 	struct reject_elem	*ap;
+	struct option_data	*options;
+	char			*type, *info;
 	ssize_t			 result;
+	void			(*handler)(struct interface_info *,
+	    struct option_data *, char *);
+	int			 i, rslt;
 
 	if ((result = receive_packet(ifi, &from, &hfrom)) == -1) {
 		ifi->errors++;
@@ -256,7 +261,69 @@ packethandler(struct interface_info *ifi)
 		    return;
 	    }
 
-	do_packet(ifi, from.sin_port, ifrom, &hfrom);
+	options = unpack_options(&ifi->recv_packet);
+
+	/*
+	 * RFC 6842 says if the server sends a client identifier
+	 * that doesn't match then the packet must be dropped.
+	 */
+	i = DHO_DHCP_CLIENT_IDENTIFIER;
+	if ((options[i].len != 0) &&
+	    ((options[i].len != config->send_options[i].len) ||
+	    memcmp(options[i].data, config->send_options[i].data,
+	    options[i].len) != 0)) {
+#ifdef DEBUG
+		log_debug("Discarding packet with client-identifier "
+		    "'%s'", pretty_print_option(i, &options[i], 0));
+#endif	/* DEBUG */
+		return;
+	}
+
+	type = "<unknown>";
+	handler = NULL;
+
+	i = DHO_DHCP_MESSAGE_TYPE;
+	if (options[i].data != NULL) {
+		/* Always try a DHCP packet, even if a bad option was seen. */
+		switch (options[i].data[0]) {
+		case DHCPOFFER:
+			handler = dhcpoffer;
+			type = "DHCPOFFER";
+			break;
+		case DHCPNAK:
+			handler = dhcpnak;
+			type = "DHCPNACK";
+			break;
+		case DHCPACK:
+			handler = dhcpack;
+			type = "DHCPACK";
+			break;
+		default:
+#ifdef DEBUG
+			log_debug("Discarding DHCP packet of unknown type "
+			    "(%d)", options[i].data[0]);
+#endif	/* DEBUG */
+			return;
+		}
+	} else if (packet->op == BOOTREPLY) {
+		handler = dhcpoffer;
+		type = "BOOTREPLY";
+	} else {
+#ifdef DEBUG
+		log_debug("Discarding packet which is neither DHCP nor BOOTP");
+#endif	/* DEBUG */
+		return;
+	}
+
+	rslt = asprintf(&info, "%s from %s (%s)", type, inet_ntoa(ifrom),
+	    ether_ntoa(&hfrom));
+	if (rslt == -1)
+		fatalx("no memory for info string");
+
+	if (handler)
+		(*handler)(ifi, options, info);
+
+	free(info);
 }
 
 void
diff --git a/sbin/dhclient/options.c b/sbin/dhclient/options.c
index 017940af84a..aa07efcee41 100644
--- a/sbin/dhclient/options.c
+++ b/sbin/dhclient/options.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: options.c,v 1.93 2017/07/06 16:56:52 krw Exp $	*/
+/*	$OpenBSD: options.c,v 1.94 2017/07/07 14:53:07 krw Exp $	*/
 
 /* DHCP options parsing and reassembly. */
 
@@ -155,12 +155,12 @@ parse_option_buffer(struct option_data *options, unsigned char *buffer,
 }
 
 /*
- * Copy as many options as fit in buflen bytes of buf. Return the
+ * Pack as many options as fit in buflen bytes of buf. Return the
  * offset of the start of the last option copied. A caller can check
  * to see if it's DHO_END to decide if all the options were copied.
  */
 int
-cons_options(unsigned char *buf, int buflen, struct option_data *options)
+pack_options(unsigned char *buf, int buflen, struct option_data *options)
 {
 	int ix, incr, length, bufix, code, lastopt = -1;
 
@@ -627,100 +627,36 @@ toobig:
 	return (optbuf);
 }
 
-void
-do_packet(struct interface_info *ifi, unsigned int from_port,
-    struct in_addr from, struct ether_addr *hfrom)
+struct option_data *
+unpack_options(struct dhcp_packet *packet)
 {
-	struct dhcp_packet *packet = &ifi->recv_packet;
-	struct option_data options[256];
-	void (*handler)(struct interface_info *, struct option_data *, char *);
-	char *type, *info;
-	int i, rslt, options_valid = 1;
+	static struct option_data options[256];
+	int i;
 
-	memset(options, 0, sizeof(options));
+	for (i = 0; i < 256; i++) {
+		free(options[i].data);
+		options[i].data = NULL;
+		options[i].len = 0;
+	}
 
 	if (memcmp(&packet->options, DHCP_OPTIONS_COOKIE, 4) == 0) {
 		/* Parse the BOOTP/DHCP options field. */
-		options_valid = parse_option_buffer(options,
-		    &packet->options[4], sizeof(packet->options) - 4);
+		parse_option_buffer(options, &packet->options[4],
+		    sizeof(packet->options) - 4);
 
-		/* Only DHCP packets have overload areas for options. */
-		if (options_valid &&
-		    options[DHO_DHCP_MESSAGE_TYPE].data &&
+		/* DHCP packets can also use overload areas for options. */
+		if (options[DHO_DHCP_MESSAGE_TYPE].data &&
 		    options[DHO_DHCP_OPTION_OVERLOAD].data) {
 			if (options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)
-				options_valid = parse_option_buffer(options,
+				parse_option_buffer(options,
 				    (unsigned char *)packet->file,
 				    sizeof(packet->file));
-			if (options_valid &&
-			    options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)
-				options_valid = parse_option_buffer(options,
+			if (options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)
+				parse_option_buffer(options,
 				    (unsigned char *)packet->sname,
 				    sizeof(packet->sname));
 		}
-
-		/*
-		 * RFC 6842 says if the server sends a client identifier
-		 * that doesn't match then the packet must be dropped.
-		 */
-		i = DHO_DHCP_CLIENT_IDENTIFIER;
-		if ((options[i].len != 0) &&
-		    ((options[i].len != config->send_options[i].len) ||
-		    memcmp(options[i].data, config->send_options[i].data,
-		    options[i].len) != 0)) {
-#ifdef DEBUG
-			log_debug("Discarding packet with client-identifier "
-			    "'%s'", pretty_print_option(i, &options[i], 0));
-#endif	/* DEBUG */
-			goto done;
-		}
-	}
-
-	type = "<unknown>";
-	handler = NULL;
-
-	if (options[DHO_DHCP_MESSAGE_TYPE].data) {
-		/* Always try a DHCP packet, even if a bad option was seen. */
-		switch (options[DHO_DHCP_MESSAGE_TYPE].data[0]) {
-		case DHCPOFFER:
-			handler = dhcpoffer;
-			type = "DHCPOFFER";
-			break;
-		case DHCPNAK:
-			handler = dhcpnak;
-			type = "DHCPNACK";
-			break;
-		case DHCPACK:
-			handler = dhcpack;
-			type = "DHCPACK";
-			break;
-		default:
-#ifdef DEBUG
-			log_debug("Discarding DHCP packet of unknown type "
-			    "(%d)", options[DHO_DHCP_MESSAGE_TYPE].data[0]);
-#endif	/* DEBUG */
-			break;
-		}
-	} else if (options_valid && packet->op == BOOTREPLY) {
-		handler = dhcpoffer;
-		type = "BOOTREPLY";
-	} else {
-#ifdef DEBUG
-		log_debug("Discarding packet which is neither DHCP nor BOOTP");
-#endif	/* DEBUG */
 	}
 
-	rslt = asprintf(&info, "%s from %s (%s)", type, inet_ntoa(from),
-	    ether_ntoa(hfrom));
-	if (rslt == -1)
-		fatalx("no memory for info string");
-
-	if (handler)
-		(*handler)(ifi, options, info);
-
-	free(info);
-
-done:
-	for (i = 0; i < 256; i++)
-		free(options[i].data);
+	return options;
 }