Cleanup/simplify parse_number():

1) Restructure to explicitly set a long long result and take the
desired low/high constraints for strtonum().

2) No need to use a temporary variable when setting long long
(a.k.a. time_t) fields.

3) Fewer magic numbers when processing integer valued option
data. Less memcpy()'ing where a cast or two is sufficient to make
integer assignment work.

No intentional functional change.

3 files changed, 35 insertions, 63 deletions

diff --git a/sbin/dhclient/clparse.c b/sbin/dhclient/clparse.c
index da0c3484538..91c63922107 100644
--- a/sbin/dhclient/clparse.c
+++ b/sbin/dhclient/clparse.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clparse.c,v 1.191 2019/07/22 15:59:49 krw Exp $	*/
+/*	$OpenBSD: clparse.c,v 1.192 2019/07/22 17:20:06 krw Exp $	*/
 
 /* Parser for dhclient config and lease files. */
 
@@ -260,7 +260,6 @@ parse_conf_decl(FILE *cfile, char *name)
 	char			*val;
 	enum actions 		*p;
 	int			 action, count, i, token;
-	uint32_t		 t;
 
 	token = next_token(NULL, cfile);
 
@@ -274,9 +273,9 @@ parse_conf_decl(FILE *cfile, char *name)
 		config->default_actions[i] = action;
 		break;
 	case TOK_BACKOFF_CUTOFF:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->backoff_cutoff, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->backoff_cutoff = ntohl(t);
 		break;
 	case TOK_DEFAULT:
 		if (parse_option(cfile, &i, config->defaults) == 0)
@@ -309,17 +308,17 @@ parse_conf_decl(FILE *cfile, char *name)
 		}
 		break;
 	case TOK_INITIAL_INTERVAL:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->initial_interval, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->initial_interval = ntohl(t);
 		break;
 	case TOK_INTERFACE:
 		parse_interface(cfile, name);
 		return;
 	case TOK_LINK_TIMEOUT:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->link_timeout, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->link_timeout = ntohl(t);
 		break;
 	case TOK_NEXT_SERVER:
 		if (parse_ip_addr(cfile, &config->next_server) == 0)
@@ -334,9 +333,9 @@ parse_conf_decl(FILE *cfile, char *name)
 		config->default_actions[i] = action;
 		break;
 	case TOK_REBOOT:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->reboot_timeout, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->reboot_timeout = ntohl(t);
 		break;
 	case TOK_REJECT:
 		if (parse_reject_statement(cfile) == 0)
@@ -353,14 +352,14 @@ parse_conf_decl(FILE *cfile, char *name)
 			return;
 		break;
 	case TOK_RETRY:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->retry_interval, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->retry_interval = ntohl(t);
 		break;
 	case TOK_SELECT_TIMEOUT:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->select_interval, 0, INT32_MAX)
+		    == 0)
 			return;
-		config->select_interval = ntohl(t);
 		break;
 	case TOK_SEND:
 		if (parse_option(cfile, &i, config->send_options) == 0)
@@ -378,9 +377,8 @@ parse_conf_decl(FILE *cfile, char *name)
 		config->default_actions[i] = ACTION_SUPERSEDE;
 		break;
 	case TOK_TIMEOUT:
-		if (parse_number(cfile, (unsigned char *)&t, 'L') == 0)
+		if (parse_number(cfile, &config->timeout, 0, INT32_MAX) == 0)
 			return;
-		config->timeout = ntohl(t);
 		break;
 	case TOK_USELEASE:
 		memset(list, 0, sizeof(list));
@@ -686,10 +684,9 @@ parse_lease_decl(FILE *cfile, struct client_lease *lease)
 		/* 'bootp' is just a comment. See BOOTP_LEASE(). */
 		break;
 	case TOK_EPOCH:
-		if (parse_number(cfile, (unsigned char *)&lease->epoch, 't')
+		if (parse_number(cfile, &lease->epoch, INT64_MIN, INT64_MAX)
 		    == 0)
 			return;
-		lease->epoch = betoh64(lease->epoch);
 		break;
 	case TOK_EXPIRE:
 		/* 'expire' is just a comment. See 'epoch'. */
@@ -777,6 +774,7 @@ parse_option(FILE *cfile, int *code, struct option_data *options)
 	struct in_addr		 ip_addr;
 	uint8_t			*dp;
 	char			*fmt, *val;
+	long long		 number;
 	unsigned int		 hunkix = 0;
 	int			 i, freedp, len, token;
 	int			 nul_term = 0;
@@ -820,26 +818,31 @@ parse_option(FILE *cfile, int *code, struct option_data *options)
 				dp = (uint8_t *)&ip_addr;
 				break;
 			case 'l':	/* Signed 32-bit integer. */
-				if (parse_number(cfile, buf, 'l') == 0)
+				if (parse_number(cfile, &number, INT32_MIN,
+				    INT32_MAX) == 0)
 					return 0;
-				len = 4;
+				*(int32_t *)buf = htobe32((int32_t)number);
+				len = sizeof(int32_t);
 				dp = buf;
 				break;
 			case 'L':	/* Unsigned 32-bit integer. */
-				if (parse_number(cfile, buf, 'L') == 0)
+				if (parse_number(cfile, &number, 0, UINT32_MAX) == 0)
 					return 0;
-				len = 4;
+				*(uint32_t *)buf = htobe32((uint32_t)number);
+				len = sizeof(uint32_t);
 				dp = buf;
 				break;
 			case 'S':	/* Unsigned 16-bit integer. */
-				if (parse_number(cfile, buf, 'S') == 0)
+				if (parse_number(cfile, &number, 0, UINT16_MAX) == 0)
 					return 0;
-				len = 2;
+				*(uint16_t *)buf = htobe16((uint16_t)number);
+				len = sizeof(uint16_t);
 				dp = buf;
 				break;
 			case 'B':	/* Unsigned 8-bit integer. */
-				if (parse_number(cfile, buf, 'B') == 0)
+				if (parse_number(cfile, &number, 0, UINT8_MAX) == 0)
 					return 0;
+				buf[0] = number;
 				len = 1;
 				dp = buf;
 				break;
diff --git a/sbin/dhclient/dhcpd.h b/sbin/dhclient/dhcpd.h
index 7ce7a100c3b..43f7e0afb39 100644
--- a/sbin/dhclient/dhcpd.h
+++ b/sbin/dhclient/dhcpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhcpd.h,v 1.280 2019/07/21 15:47:02 krw Exp $	*/
+/*	$OpenBSD: dhcpd.h,v 1.281 2019/07/22 17:20:06 krw Exp $	*/
 
 /*
  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
@@ -182,7 +182,7 @@ int		 parse_semi(FILE *);
 int		 parse_string(FILE *, char **);
 int		 parse_ip_addr(FILE *, struct in_addr *);
 int		 parse_cidr(FILE *, unsigned char *);
-int		 parse_number(FILE *, unsigned char *, char);
+int		 parse_number(FILE *, long long *, long long, long long);
 int		 parse_boolean(FILE *, unsigned char *);
 void		 parse_warn(char *);
 
diff --git a/sbin/dhclient/parse.c b/sbin/dhclient/parse.c
index 946e056cb13..fd0f7cbadc9 100644
--- a/sbin/dhclient/parse.c
+++ b/sbin/dhclient/parse.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parse.c,v 1.82 2019/07/21 15:59:51 krw Exp $	*/
+/*	$OpenBSD: parse.c,v 1.83 2019/07/22 17:20:06 krw Exp $	*/
 
 /* Common parser code for dhcpd and dhclient. */
 
@@ -251,49 +251,18 @@ parse_boolean(FILE *cfile, unsigned char *buf)
 }
 
 int
-parse_number(FILE *cfile, unsigned char *buf, char fmt)
+parse_number(FILE *cfile, long long *number, long long low, long long high)
 {
 	const char	*errstr;
 	char		*val, *msg;
-	int		 bytes, rslt, token;
-	long long	 numval, low, high;
+	int		 rslt, token;
+	long long	 numval;
 
 	token = next_token(&val, cfile);
 
-	switch (fmt) {
-	case 't':	/* Signed 64-bit integer. */
-		low = INT64_MIN;
-		high = INT64_MAX;
-		bytes = 8;
-		break;
-	case 'l':	/* Signed 32-bit integer. */
-		low = INT32_MIN;
-		high = INT32_MAX;
-		bytes = 4;
-		break;
-	case 'L':	/* Unsigned 32-bit integer. */
-		low = 0;
-		high = UINT32_MAX;
-		bytes = 4;
-		break;
-	case 'S':	/* Unsigned 16-bit integer. */
-		low = 0;
-		high = UINT16_MAX;
-		bytes = 2;
-		break;
-	case 'B':	/* Unsigned 8-bit integer. */
-		low = 0;
-		high = UINT8_MAX;
-		bytes = 1;
-		break;
-	default:
-		return 0;
-	}
-
 	numval = strtonum(val, low, high, &errstr);
 	if (errstr == NULL) {
-		numval = htobe64(numval);
-		memcpy(buf, (char *)&numval + (sizeof(numval) - bytes), bytes);
+		*number = numval;
 		return 1;
 	}