From cbfbc5190786639e07f1e30de9b06f6a7c9818f3 Mon Sep 17 00:00:00 2001
From: krw <krw@openbsd.org>
Date: Sun, 9 Jul 2017 18:45:27 +0000
Subject: [PATCH] Some parsing code cleanup: add parse_boolean(); pass literal
 format chars to parse_decimal() instead of less obvious *fmt; refactor to
 eliminate need for the 'alloc:' and 'bad_flag:' labels and the invidious
 backwards goto's to them.

---
 sbin/dhclient/clparse.c | 62 +++++++++++++++++------------------------
 sbin/dhclient/dhcpd.h   |  3 +-
 sbin/dhclient/parse.c   | 25 ++++++++++++++++-
 3 files changed, 52 insertions(+), 38 deletions(-)

diff --git a/sbin/dhclient/clparse.c b/sbin/dhclient/clparse.c
index afe5db7b61e..dd707782703 100644
--- a/sbin/dhclient/clparse.c
+++ b/sbin/dhclient/clparse.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clparse.c,v 1.119 2017/07/08 20:38:31 krw Exp $	*/
+/*	$OpenBSD: clparse.c,v 1.120 2017/07/09 18:45:27 krw Exp $	*/
 
 /* Parser for dhclient config and lease files. */
 
@@ -654,6 +654,7 @@ parse_option_decl(FILE *cfile, struct option_data *options)
 				if (len == -1)
 					return (-1);
 				hunkix += len;
+				dp = NULL;
 				break;
 			case 't': /* Text string. */
 				val = parse_string(cfile, &len);
@@ -669,24 +670,16 @@ parse_option_decl(FILE *cfile, struct option_data *options)
 				nul_term = 1;
 				hunkix += len;
 				free(val);
+				dp = NULL;
 				break;
 			case 'I': /* IP address. */
 				if (!parse_ip_addr(cfile, &ip_addr))
 					return (-1);
 				len = sizeof(ip_addr);
 				dp = (uint8_t *)&ip_addr;
-alloc:
-				if (hunkix + len > sizeof(hunkbuf)) {
-					parse_warn("option data buffer "
-					    "overflow");
-					skip_to_semi(cfile);
-					return (-1);
-				}
-				memcpy(&hunkbuf[hunkix], dp, len);
-				hunkix += len;
 				break;
 			case 'l':	/* Signed 32-bit integer. */
-				if (!parse_decimal(cfile, buf, *fmt)) {
+				if (!parse_decimal(cfile, buf, 'l')) {
 					parse_warn("expecting signed 32-bit "
 					    "integer.");
 					skip_to_semi(cfile);
@@ -694,9 +687,9 @@ alloc:
 				}
 				len = 4;
 				dp = buf;
-				goto alloc;
+				break;
 			case 'L':	/* Unsigned 32-bit integer. */
-				if (!parse_decimal(cfile, buf, *fmt)) {
+				if (!parse_decimal(cfile, buf, 'L')) {
 					parse_warn("expecting unsigned 32-bit "
 					    "integer.");
 					skip_to_semi(cfile);
@@ -704,9 +697,9 @@ alloc:
 				}
 				len = 4;
 				dp = buf;
-				goto alloc;
+				break;
 			case 'S':	/* Unsigned 16-bit integer. */
-				if (!parse_decimal(cfile, buf, *fmt)) {
+				if (!parse_decimal(cfile, buf, 'S')) {
 					parse_warn("expecting unsigned 16-bit "
 					    "integer.");
 					skip_to_semi(cfile);
@@ -714,9 +707,9 @@ alloc:
 				}
 				len = 2;
 				dp = buf;
-				goto alloc;
+				break;
 			case 'B':	/* Unsigned 8-bit integer. */
-				if (!parse_decimal(cfile, buf, *fmt)) {
+				if (!parse_decimal(cfile, buf, 'B')) {
 					parse_warn("expecting unsigned 8-bit "
 					    "integer.");
 					skip_to_semi(cfile);
@@ -724,41 +717,38 @@ alloc:
 				}
 				len = 1;
 				dp = buf;
-				goto alloc;
+				break;
 			case 'f': /* Boolean flag. */
-				token = next_token(&val, cfile);
-				if (!is_identifier(token)) {
-					parse_warn("expecting identifier.");
-bad_flag:
-					if (token != ';')
-						skip_to_semi(cfile);
-					return (-1);
-				}
-				if (!strcasecmp(val, "true") ||
-				    !strcasecmp(val, "on"))
-					buf[0] = 1;
-				else if (!strcasecmp(val, "false") ||
-				    !strcasecmp(val, "off"))
-					buf[0] = 0;
-				else {
+				if (!parse_boolean(cfile, buf)) {
 					parse_warn("expecting boolean.");
-					goto bad_flag;
+					skip_to_semi(cfile);
+					return (-1);
 				}
 				len = 1;
 				dp = buf;
-				goto alloc;
+				break;
 			case 'C':
 				if (!parse_cidr(cfile, cidr))
 					return (-1);
 				len = 1 + (cidr[0] + 7) / 8;
 				dp = cidr;
-				goto alloc;
+				break;
 			default:
 				log_warnx("Bad format %c in "
 				    "parse_option_param.", *fmt);
 				skip_to_semi(cfile);
 				return (-1);
 			}
+			if (dp != NULL && len > 0) {
+				if (hunkix + len > sizeof(hunkbuf)) {
+					parse_warn("option data buffer "
+					    "overflow");
+					skip_to_semi(cfile);
+					return (-1);
+				}
+				memcpy(&hunkbuf[hunkix], dp, len);
+				hunkix += len;
+			}
 		}
 		token = peek_token(NULL, cfile);
 		if (*fmt == 'A' && token == ',')
diff --git a/sbin/dhclient/dhcpd.h b/sbin/dhclient/dhcpd.h
index 45d504b706d..3c008200775 100644
--- a/sbin/dhclient/dhcpd.h
+++ b/sbin/dhclient/dhcpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhcpd.h,v 1.209 2017/07/08 20:38:31 krw Exp $	*/
+/*	$OpenBSD: dhcpd.h,v 1.210 2017/07/09 18:45:27 krw Exp $	*/
 
 /*
  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
@@ -191,6 +191,7 @@ int parse_cidr(FILE *, unsigned char *);
 void parse_lease_time(FILE *, time_t *);
 int parse_decimal(FILE *, unsigned char *, char);
 int parse_hex(FILE *, unsigned char *);
+int parse_boolean(FILE *, unsigned char *);
 time_t parse_date(FILE *);
 void parse_warn(char *);
 
diff --git a/sbin/dhclient/parse.c b/sbin/dhclient/parse.c
index a88469a0942..841841d9093 100644
--- a/sbin/dhclient/parse.c
+++ b/sbin/dhclient/parse.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.c,v 1.55 2017/07/08 00:36:10 krw Exp $	*/
+/*	$OpenBSD: parse.c,v 1.56 2017/07/09 18:45:27 krw Exp $	*/
 
 /* Common parser code for dhcpd and dhclient. */
 
@@ -245,6 +245,29 @@ parse_lease_time(FILE *cfile, time_t *timep)
 	parse_semi(cfile);
 }
 
+int
+parse_boolean(FILE *cfile, unsigned char *buf)
+{
+	char	*val;
+	int	 token;
+
+	token = next_token(&val, cfile);
+	if (is_identifier(token)) {
+		if (strcasecmp(val, "true") == 0 ||
+		    strcasecmp(val, "on") == 0) {
+			buf[0] = 1;
+			return (1);
+		}
+		if (strcasecmp(val, "false") == 0 ||
+		    strcasecmp(val, "off") == 0) {
+			buf[0] = 0;
+			return (1);
+		}
+	}
+
+	return (0);
+}
+
 int
 parse_decimal(FILE *cfile, unsigned char *buf, char fmt)
 {
-- 
2.20.1