doas(1): porting OpenBSD doas(1) command to NetBSD.

nbsd-doas.diff

diff --git a/usr.bin/doas/Makefile b/usr.bin/doas/Makefile
index 809fe0b..6610edb 100644
--- a/usr.bin/doas/Makefile
+++ b/usr.bin/doas/Makefile
@@ -1,14 +1,31 @@
+#	$NetBSD$
 #	$OpenBSD: Makefile,v 1.1 2015/07/16 20:44:21 tedu Exp $
 
-SRCS=	parse.y doas.c
+.include <bsd.own.mk>
+
+USE_FORT?=yes
+WARN=	4
 
 PROG=	doas
+SRCS=	parse.y doas.c
 MAN=	doas.1 doas.conf.5
 
-BINOWN= root
+BINOWN=	root
 BINMODE=4555
 
-CFLAGS+= -I${.CURDIR}
-COPTS+=	-Wall
+CPPFLAGS+=-I${.CURDIR}
+CPPFLAGS+=-DHAVE_LOGIN_CAP_H
+CPPFLAGS+=-DHAVE_INTTYPES_H
+CPPFLAGS+=-DHAVE_REALLOCARR
+CPPFLAGS+=-DHAVE_STRTOI
+
+DPADD+=	${LIBUTIL}
+LDADD+=	-lutil
+
+.if ${MKPAM} != "no"
+CPPFLAGS+= -DUSE_PAM
+LDADD+= -lpam ${PAM_STATIC_LDADD}
+DPADD+= ${LIBPAM} ${PAM_STATIC_DPADD}
+.endif
 
 .include <bsd.prog.mk>
diff --git a/usr.bin/doas/doas.1 b/usr.bin/doas/doas.1
index b9bf0d3..2e33b54 100644
--- a/usr.bin/doas/doas.1
+++ b/usr.bin/doas/doas.1
@@ -1,3 +1,4 @@
+.\" $NetBSD$
 .\" $OpenBSD: doas.1,v 1.1 2015/07/16 20:44:21 tedu Exp $
 .\"
 .\"Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
diff --git a/usr.bin/doas/doas.c b/usr.bin/doas/doas.c
index 3570cca..7ef2d64 100644
--- a/usr.bin/doas/doas.c
+++ b/usr.bin/doas/doas.c
@@ -1,3 +1,4 @@
+/* $NetBSD$ */
 /* $OpenBSD: doas.c,v 1.6 2015/07/16 23:22:08 nicm Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
@@ -18,9 +19,10 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 
+#if defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#endif
 #include <limits.h>
-#include <login_cap.h>
-#include <bsd_auth.h>
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -30,6 +32,21 @@
 #include <grp.h>
 #include <syslog.h>
 
+#if defined(HAVE_LOGIN_CAP_H)
+#include <login_cap.h>
+#endif
+
+#if defined(USE_BSD_AUTH)
+#include <bsd_auth.h>
+#endif
+
+#if defined(USE_PAM)
+#include <security/pam_appl.h>
+#include <security/openpam.h>
+
+static struct pam_conv pamc = { openpam_ttyconv, NULL };
+#endif
+
 #include "doas.h"
 
 static void __dead
@@ -40,7 +57,7 @@ usage(void)
 }
 
 size_t
-arraylen(const char **arr)
+arraylen(const char * const *arr)
 {
 	size_t cnt = 0;
 	while (*arr) {
@@ -54,15 +71,25 @@ static int
 parseuid(const char *s, uid_t *uid)
 {
 	struct passwd *pw;
+#if defined(HAVE_STRTONUM)
 	const char *errstr;
+#else
+	int error;
+#endif
 
 	if ((pw = getpwnam(s)) != NULL) {
 		*uid = pw->pw_uid;
 		return 0;
 	}
+#if defined(HAVE_STRTONUM)
 	*uid = strtonum(s, 0, UID_MAX, &errstr);
 	if (errstr)
 		return -1;
+#else
+	*uid = strtoi(s, NULL, 10, 0, UID_MAX, &error);
+	if (error)
+		return -1;
+#endif
 	return 0;
 }
 
@@ -82,14 +109,24 @@ static gid_t
 strtogid(const char *s)
 {
 	struct group *gr;
-	const char *errstr;
 	gid_t gid;
+#if defined(HAVE_STRTONUM)
+	const char *errstr;
+#else
+	int error;
+#endif
 
 	if ((gr = getgrnam(s)) != NULL)
 		return gr->gr_gid;
+#if defined(HAVE_STRTONUM)
 	gid = strtonum(s, 0, GID_MAX, &errstr);
 	if (errstr)
 		return -1;
+#else
+	gid = strtoi(s, NULL, 10, 0, GID_MAX, &error);
+	if (error)
+		return -1;
+#endif
 	return gid;
 }
 
@@ -101,7 +138,7 @@ match(uid_t uid, gid_t *groups, int ngroups, uid_t target, const char *cmd,
 
 	if (r->ident[0] == ':') {
 		gid_t rgid = strtogid(r->ident + 1);
-		if (rgid == -1)
+		if (rgid == (gid_t)-1)
 			return 0;
 		for (i = 0; i < ngroups; i++) {
 			if (rgid == groups[i])
@@ -161,12 +198,12 @@ parseconfig(const char *filename)
 }
 
 static int
-copyenvhelper(const char **oldenvp, const char **safeset, int nsafe,
+copyenvhelper(const char * const *oldenvp, const char **safeset, int nsafe,
     char **envp, int ei)
 {
 	int i;
 	for (i = 0; i < nsafe; i++) {
-		const char **oe = oldenvp;
+		const char * const *oe = oldenvp;
 		while (*oe) {
 			size_t len = strlen(safeset[i]);
 			if (strncmp(*oe, safeset[i], len) == 0 &&
@@ -182,9 +219,9 @@ copyenvhelper(const char **oldenvp, const char **safeset, int nsafe,
 }
 
 static char **
-copyenv(const char **oldenvp, struct rule *rule)
+copyenv(const char * const *oldenvp, struct rule *rule)
 {
-	const char *safeset[] = {
+	static const char *safeset[] = {
 		"DISPLAY", "HOME", "LOGNAME", "MAIL", "SHELL",
 		"PATH", "TERM", "USER", "USERNAME",
 		NULL,
@@ -195,12 +232,18 @@ copyenv(const char **oldenvp, struct rule *rule)
 	const char **extra;
 	int ei;
 	int i, j;
-	
+
 	if ((rule->options & KEEPENV) && !rule->envlist) {
 		j = arraylen(oldenvp);
+#if defined(HAVE_REALLOCARRAY)
 		envp = reallocarray(NULL, j + 1, sizeof(char *));
 		if (!envp)
 			err(1, "reallocarray");
+#else
+		envp = NULL;
+		if (reallocarr(&envp, j + 1, sizeof(char *)))
+			err(1, "reallocarr");
+#endif
 		for (i = 0; i < j; i++) {
 			if (!(envp[i] = strdup(oldenvp[i])))
 				err(1, "strdup");
@@ -222,9 +265,15 @@ copyenv(const char **oldenvp, struct rule *rule)
 		}
 	}
 
+#if defined(HAVE_REALLOCARRAY)
 	envp = reallocarray(NULL, nsafe + nextras + 1, sizeof(char *));
 	if (!envp)
 		err(1, "can't allocate new environment");
+#else
+	envp = NULL;
+	if (reallocarr(&envp, nsafe + nextras + 1, sizeof(char *)))
+		err(1, "can't allocate new environment");
+#endif
 
 	ei = 0;
 	ei = copyenvhelper(oldenvp, safeset, nsafe, envp, ei);
@@ -244,6 +293,8 @@ fail(void)
 int
 main(int argc, char **argv, char **envp)
 {
+	static const char *safepath = "/bin:/sbin:/usr/bin:/usr/sbin:"
+	    "/usr/local/bin:/usr/local/sbin";
 	char cmdline[1024];
 	char myname[32];
 	uid_t uid, target = 0;
@@ -253,8 +304,11 @@ main(int argc, char **argv, char **envp)
 	struct rule *rule;
 	const char *cmd;
 	int i, ch;
-	const char *safepath = "/bin:/sbin:/usr/bin:/usr/sbin:"
-	    "/usr/local/bin:/usr/local/sbin";
+#if defined(USE_PAM)
+	pam_handle_t *pamh = NULL;
+	int pam_err;
+	int pam_silent = PAM_SILENT;
+#endif
 
 	parseconfig("/etc/doas.conf");
 
@@ -299,22 +353,84 @@ main(int argc, char **argv, char **envp)
 	}
 
 	if (!(rule->options & NOPASS)) {
+#if defined(USE_BSD_AUTH)
 		if (!auth_userokay(myname, NULL, NULL, NULL)) {
 			syslog(LOG_AUTHPRIV | LOG_NOTICE,
 			    "failed password for %s", myname);
 			fail();
 		}
+#elif defined(USE_PAM)
+#define PAM_END(msg) do { 						\
+	syslog(LOG_ERR, "%s: %s", msg, pam_strerror(pamh, pam_err)); 	\
+	warnx("%s: %s", msg, pam_strerror(pamh, pam_err));		\
+	pam_end(pamh, pam_err);						\
+	exit(EXIT_FAILURE);						\
+} while (/*CONSTCOND*/0)
+
+		pam_err = pam_start("doas", myname, &pamc, &pamh);
+		if (pam_err != PAM_SUCCESS) {
+			if (pamh != NULL)
+				PAM_END("pam_start");
+			syslog(LOG_ERR, "pam_start failed: %s",
+			    pam_strerror(pamh, pam_err));
+			errx(EXIT_FAILURE, "pam_start failed");
+		}
+
+		switch (pam_err = pam_authenticate(pamh, pam_silent)) {
+		case PAM_SUCCESS:
+			switch (pam_err = pam_acct_mgmt(pamh, pam_silent)) {
+			case PAM_SUCCESS:
+				break;
+
+			case PAM_NEW_AUTHTOK_REQD:
+				pam_err = pam_chauthtok(pamh,
+				    pam_silent|PAM_CHANGE_EXPIRED_AUTHTOK);
+				if (pam_err != PAM_SUCCESS)
+					PAM_END("pam_chauthtok");
+				break;
+
+			case PAM_AUTH_ERR:
+			case PAM_USER_UNKNOWN:
+			case PAM_MAXTRIES:
+				syslog(LOG_AUTHPRIV | LOG_NOTICE,
+				    "failed auth for %s", myname);
+				fail();
+				break;
+
+			default:
+				PAM_END("pam_acct_mgmt");
+				break;
+			}
+			break;
+
+		case PAM_AUTH_ERR:
+		case PAM_USER_UNKNOWN:
+		case PAM_MAXTRIES:
+			syslog(LOG_AUTHPRIV | LOG_NOTICE,
+			    "failed auth for %s", myname);
+			fail();
+			break;
+
+		default:
+			PAM_END("pam_authenticate");
+			break;
+		}
+		pam_end(pamh, pam_err);
+#else
+#error	No auth module!
+#endif
 	}
-	envp = copyenv((const char **)envp, rule);
+	envp = copyenv((const char * const *)envp, rule);
 
 	pw = getpwuid(target);
 	if (!pw)
 		errx(1, "no passwd entry for target");
+#if defined(HAVE_LOGIN_CAP_H)
 	if (setusercontext(NULL, pw, target, LOGIN_SETGROUP |
 	    LOGIN_SETPRIORITY | LOGIN_SETRESOURCES | LOGIN_SETUMASK |
 	    LOGIN_SETUSER) != 0)
 		errx(1, "failed to set user context for target");
-
+#endif
 	syslog(LOG_AUTHPRIV | LOG_INFO, "%s ran command as %s: %s",
 	    myname, pw->pw_name, cmdline);
 	setenv("PATH", safepath, 1);
diff --git a/usr.bin/doas/doas.conf.5 b/usr.bin/doas/doas.conf.5
index ddfdfd6..4fd85e2 100644
--- a/usr.bin/doas/doas.conf.5
+++ b/usr.bin/doas/doas.conf.5
@@ -1,3 +1,4 @@
+.\" $NetBSD$
 .\" $OpenBSD: doas.conf.5,v 1.2 2015/07/16 21:24:07 nicm Exp $
 .\"
 .\"Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
diff --git a/usr.bin/doas/doas.h b/usr.bin/doas/doas.h
index b6d0275..4af3fd2 100644
--- a/usr.bin/doas/doas.h
+++ b/usr.bin/doas/doas.h
@@ -1,3 +1,4 @@
+/*	$NetBSD$	*/
 
 struct rule {
 	int action;
@@ -11,10 +12,30 @@ struct rule {
 extern struct rule **rules;
 extern int nrules, maxrules;
 
-size_t arraylen(const char **);
+size_t arraylen(const char * const *);
 
 #define PERMIT	1
 #define DENY	2
 
 #define NOPASS		0x1
 #define KEEPENV		0x2
+
+#if !defined(HAVE_REALLOCARRAY) && !defined(HAVE_REALLOCARR)
+int reallocarr(void *ptr, size_t num, size_t size);
+#endif	/* !HAVE_REALLOCARRAY && !HAVE_REALLOCARR */
+
+#if !defined(HAVE_STRTOI) && !defined(HAVE_STRTONUM)
+#if defined(HAVE_INTTYPES_H)
+#include <stdint.h>
+#elif defined(HAVE_LONG_LONG_INT)
+typedef long long       intmax_t;
+#else	/* !HAVE_INTTYPES_H && !HAVE_LONG_LONG_INT */
+typedef long            intmax_t;
+#endif	/* HAVE_LONG_LONG_INT */
+intmax_t strtoi(const char *nptr, char **endptr, int base, intmax_t lo,
+	    intmax_t hi, int *rstatus);
+#endif	/* !HAVE_STRTOI && !HAVE_STRTONUM */
+
+#if !defined(HAVE_EXECVPE)
+int execvpe(const char *file, char * const *argv, char * const *envp);
+#endif	/* !HAVE_EXECVPE */
diff --git a/usr.bin/doas/execvpe.c b/usr.bin/doas/execvpe.c
new file mode 100644
index 0000000..4a74d4b
--- /dev/null
+++ b/usr.bin/doas/execvpe.c
@@ -0,0 +1,48 @@
+/*	$NetBSD$	*/
+
+/*-
+ * Copyright (C) 2015 NONAKA Kimihiro <nonakap@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <unistd.h>
+
+#include "doas.h"
+
+#if !defined(HAVE_EXECVPE)
+
+extern char **environ;
+
+int
+execvpe(const char *file, char * const *argv, char * const *envp)
+{
+	char **oldenvp = environ;
+	int error;
+
+	environ = (char **)(long)envp;	/* XXX */
+	error = execvp(file, argv);
+	environ = oldenvp;
+	return error;
+}
+
+#endif	/* !HAVE_EXECVPE */
diff --git a/usr.bin/doas/parse.y b/usr.bin/doas/parse.y
index 089dc4f..9b084c2 100644
--- a/usr.bin/doas/parse.y
+++ b/usr.bin/doas/parse.y
@@ -1,3 +1,4 @@
+/* $NetBSD$ */
 /* $OpenBSD: parse.y,v 1.4 2015/07/16 23:02:56 nicm Exp $ */
 /*
  * Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
@@ -23,6 +24,7 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 #include <err.h>
 
 #include "doas.h"
@@ -77,8 +79,13 @@ rule:		action ident target cmd {
 					maxrules = 63;
 				else
 					maxrules *= 2;
+#if defined(HAVE_REALLOCARRAY)
 				if (!(rules = reallocarray(rules, maxrules, sizeof(*rules))))
 					errx(1, "can't allocate rules");
+#else
+				if (reallocarr(&rules, maxrules, sizeof(*rules)))
+					errx(1, "can't allocate rules");
+#endif
 			}
 			rules[nrules++] = r;
 		} ;
@@ -116,8 +123,14 @@ envlist:	/* empty */ {
 				errx(1, "can't allocate envlist");
 		} | envlist TSTRING {
 			int nenv = arraylen($1.envlist);
+#if defined(HAVE_REALLOCARRAY)
 			if (!($$.envlist = reallocarray($1.envlist, nenv + 2, sizeof(char *))))
 				errx(1, "can't allocate envlist");
+#else
+			$$.envlist = $1.envlist;
+			if (reallocarr(&$$.envlist, nenv + 2, sizeof(char *)))
+				errx(1, "can't allocate envlist");
+#endif
 			$$.envlist[nenv] = $2.str;
 			$$.envlist[nenv + 1] = NULL;
 		}
@@ -150,7 +163,7 @@ yyerror(const char *fmt, ...)
 	verrx(1, fmt, va);
 }
 
-struct keyword {
+static const struct keyword {
 	const char *word;
 	int token;
 } keywords[] = {
@@ -206,7 +219,7 @@ eow:
 	*p = 0;
 	if (c != EOF)
 		ungetc(c, yyfp);
-	for (i = 0; i < sizeof(keywords) / sizeof(keywords[0]); i++) {
+	for (i = 0; i < (int)(sizeof(keywords) / sizeof(keywords[0])); i++) {
 		if (strcmp(buf, keywords[i].word) == 0)
 			return keywords[i].token;
 	}
diff --git a/usr.bin/doas/reallocarr.c b/usr.bin/doas/reallocarr.c
new file mode 100644
index 0000000..342bba2
--- /dev/null
+++ b/usr.bin/doas/reallocarr.c
@@ -0,0 +1,73 @@
+/* $NetBSD$ */
+/* NetBSD: reallocarr.c,v 1.2 2015/07/16 00:03:59 kamil Exp */
+
+/*-
+ * Copyright (c) 2015 Joerg Sonnenberger <joerg@NetBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <errno.h>
+/* Old POSIX has SIZE_MAX in limits.h */
+#include <limits.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "doas.h"
+
+#if !defined(HAVE_REALLOCARR) && !defined(HAVE_REALLOCARRAY)
+
+int
+reallocarr(void *ptr, size_t num, size_t size)
+{
+	int saved_errno, result;
+	void *optr;
+	void *nptr;
+
+	saved_errno = errno;
+	memcpy(&optr, ptr, sizeof(ptr));
+	if (num == 0 || size == 0) {
+		free(optr);
+		nptr = NULL;
+		memcpy(ptr, &nptr, sizeof(ptr));
+		errno = saved_errno;
+		return 0;
+	}
+	if ((num >= 65535 || size >= 65535) && num > SIZE_MAX / size)
+		return EOVERFLOW;
+	nptr = realloc(optr, num * size);
+	if (nptr == NULL) {
+		result = errno;
+	} else {
+		result = 0;
+		memcpy(ptr, &nptr, sizeof(ptr));
+	}
+	errno = saved_errno;
+	return result;
+}
+
+#endif	/* !HAVE_REALLOCARR && !HAVE_REALLOCARRAY */
diff --git a/usr.bin/doas/strtoi.c b/usr.bin/doas/strtoi.c
new file mode 100644
index 0000000..ec6481f
--- /dev/null
+++ b/usr.bin/doas/strtoi.c
@@ -0,0 +1,102 @@
+/*	$NetBSD$	*/
+/*	NetBSD: _strtoi.h,v 1.2 2015/01/18 17:55:22 christos Exp	*/
+
+/*-
+ * Copyright (c) 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * Original version ID:
+ * NetBSD: src/lib/libc/locale/_wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp
+ *
+ * Created by Kamil Rytarowski, based on ID:
+ * NetBSD: src/common/lib/libc/stdlib/_strtoul.h,v 1.7 2013/05/17 12:55:56 joerg Exp
+ */
+
+#if defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#endif
+#include <stdlib.h>
+#include <errno.h>
+
+#include "doas.h"
+
+#if !defined(HAVE_STRTOI) && !defined(HAVE_STRTONUM)
+
+#if defined(HAVE_STRTOIMAX)
+#define	STRTOIMAX	strtoimax
+#elif defined(HAVE_STRTOLL)
+#define	STRTOIMAX	strtoll
+#else
+#define	STRTOIMAX	strtol
+#endif
+
+intmax_t
+strtoi(const char *nptr, char **endptr, int base, intmax_t lo, intmax_t hi,
+    int *rstatus)
+{
+	int serrno;
+	intmax_t im;
+	char *ep;
+	int rep;
+
+	if (endptr == NULL)
+		endptr = &ep;
+	if (rstatus == NULL)
+		rstatus = &rep;
+
+	serrno = errno;
+	errno = 0;
+
+	im = STRTOIMAX(nptr, endptr, base);
+
+	*rstatus = errno;
+	errno = serrno;
+
+	if (*rstatus == 0) {
+		/* No digits were found */
+		if (nptr == *endptr)
+			*rstatus = ECANCELED;
+		/* There are further characters after number */
+		else if (**endptr != '\0')
+			*rstatus = ENOTSUP;
+	}
+
+	if (im < lo) {
+		if (*rstatus == 0)
+			*rstatus = ERANGE;
+		return lo;
+	}
+	if (im > hi) {
+		if (*rstatus == 0)
+			*rstatus = ERANGE;
+		return hi;
+	}
+
+	return im;
+}
+
+#endif	/* !HAVE_STRTOI && !HAVE_STRTONUM */