Next round! This does

 * implement warnings close to Solaris 8:
    - print a warning if the login name is non-standard (see documentation 
      for what's considered "standard")
    - print a warning on all-uppercase login names
    - print a warning if the first char of the login name is not a letter
 * update documentation to describe what a "standard" login is
 * use shquote(3), with it's own implementation for <1.6
 * follow the idea to give the administrator the rope he asks for

Suggestions for improvement welcome, else I'll look into committing this
soonish. Thanks!


  - Hubert

Index: user.c
===================================================================
RCS file: /cvsroot/basesrc/usr.sbin/user/user.c,v
retrieving revision 1.20.4.8
diff -u -r1.20.4.8 user.c
--- user.c	2001/02/26 18:01:17	1.20.4.8
+++ user.c	2001/11/23 03:11:21
@@ -45,6 +45,7 @@
 #include <ctype.h>
 #include <dirent.h>
 #include <err.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <grp.h>
 #include <paths.h>
@@ -213,6 +214,219 @@
 	return ret;
 }
 
+#define NetBSD_1_6	106000100
+#if defined(__NetBSD_Version__) && (__NetBSD_Version__ < NetBSD_1_6)
+/* from src/lib/libc/gen/shquote.c, needed for the useradd pkg which
+ * also needs to run on < 1.6
+ */
+
+size_t
+shquote(const char *arg, char *buf, size_t bufsize);
+
+
+/* <<NetBSD: shquote.c,v 1.4 2001/03/12 03:20:10 simonb Exp>> */
+
+/*
+ * Copyright (c) 2001 Christopher G. Demetriou
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *          This product includes software developed for the
+ *          NetBSD Project.  See http://www.netbsd.org/ for
+ *          information about NetBSD.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ * 
+ * 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.
+ * 
+ * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
+ */
+
+/*
+ * Define SHQUOTE_USE_MULTIBYTE if you want shquote() to handle multibyte
+ * characters using mbrtowc().
+ *
+ * Please DO NOT rip this #ifdef out of the code.  It's also here to help
+ * portability.
+ */
+#undef	SHQUOTE_USE_MULTIBYTE
+
+#ifdef SHQUOTE_USE_MULTIBYTE
+#include <limits.h>
+#include <wchar.h>
+#endif
+
+/*
+ * shquote():
+ *
+ * Requotes arguments so that they'll be interpreted properly by the
+ * shell (/bin/sh).
+ *
+ * Wraps single quotes around the string, and replaces single quotes
+ * in the string with the sequence:
+ *	'\''
+ *
+ * Returns the number of characters required to hold the resulting quoted
+ * argument.
+ *
+ * The buffer supplied is filled in and NUL-terminated.  If 'bufsize'
+ * indicates that the buffer is too short to hold the output string, the
+ * first (bufsize - 1) bytes of quoted argument are filled in and the
+ * buffer is NUL-terminated.
+ *
+ * Changes could be made to optimize the length of strings output by this
+ * function:
+ *
+ *	* if there are no metacharacters or whitespace in the input,
+ *	  the output could be the input string.
+ */
+
+#ifdef SHQUOTE_USE_MULTIBYTE
+
+#define	XLATE_OUTCH(x)		wcrtomb(outch, (x), &mbso)
+#define	XLATE_INCH()						\
+    do {							\
+	n = mbrtowc(&c, arg, MB_CUR_MAX, &mbsi);		\
+    } while (/*LINTED const cond*/0)
+
+#else
+
+#define	XLATE_OUTCH(x)		(outch[0] = (x), 1)
+#define	XLATE_INCH()						\
+    do {							\
+	n = ((c = *arg) != '\0') ? 1 : 0;			\
+    } while (/*LINTED const cond*/0)
+
+#endif
+
+#define	PUT(x)							\
+    do {							\
+	outchlen = XLATE_OUTCH(x);				\
+	if (outchlen == (size_t)-1)				\
+		goto bad;					\
+	rv += outchlen;						\
+	if (bufsize != 0) {					\
+		if (bufsize < outchlen ||			\
+		    (bufsize == outchlen &&			\
+		     outch[outchlen - 1] != '\0')) {		\
+			*buf = '\0';				\
+			bufsize = 0;				\
+		} else {					\
+			memcpy(buf, outch, outchlen);		\
+			buf += outchlen;			\
+			bufsize -= outchlen;			\
+		}						\
+	}							\
+    } while (/*LINTED const cond*/0)
+
+size_t
+shquote(const char *arg, char *buf, size_t bufsize)
+{
+#ifdef SHQUOTE_USE_MULTIBYTE
+	char outch[MB_LEN_MAX];
+	mbstate_t mbsi, mbso;
+	wchar_t c, lastc;
+	size_t outchlen;
+#else
+	char outch[1];
+	char c, lastc;
+	size_t outchlen;
+#endif
+	size_t rv;
+	int n;
+
+	rv = 0;
+	lastc = 0;
+#ifdef SHQUOTE_USE_MULTIBYTE
+	memset(&mbsi, 0, sizeof mbsi);
+	memset(&mbso, 0, sizeof mbso);
+#endif
+
+	if (*arg != '\'')
+		PUT('\'');
+	for (;;) {
+		XLATE_INCH();
+		if (n == (size_t)-1)
+			goto bad;
+		if (n <= 0)
+			break;
+		arg += n;
+		lastc = c;
+
+		if (c == '\'') {
+			if (rv != 0)
+				PUT('\'');
+			PUT('\\');
+			PUT('\'');
+			for (;;) {
+				XLATE_INCH();
+				if (n <= 0 || c != '\'')
+					break;
+				PUT('\\');
+				PUT('\'');
+				arg += n;
+			}
+			if (n > 0)
+				PUT('\'');
+		} else
+			PUT(c);
+	}
+	if (lastc != '\'')
+		PUT('\'');
+
+	/* Put multibyte or NUL terminator, but don't count the NUL. */
+	PUT('\0');
+	rv--;
+
+	return rv;
+
+bad:
+	/* A multibyte character encoding or decoding error occurred. */
+	return (size_t)-1;
+}
+#endif /* < NetBSD 1.6 */
+
+
+/* quote shell metachars in a string */
+/* caller should free(3) returned string */
+static char *
+quote(const char *str)
+{
+	char	*buf;
+	size_t	rc;
+	size_t	bufsize;
+
+	bufsize = 4*strlen(str) + 1;
+	buf = malloc(bufsize);
+	if (buf == NULL)
+		errx(EXIT_FAILURE, "Cannot allocate memory in quote()");
+	
+	rc = shquote(str, buf, bufsize);
+	if (rc == (size_t)-1) {
+		errx(EXIT_FAILURE, "shquote() returned -1");
+	}
+
+	return buf;
+}
+
 /* remove a users home directory, returning 1 for success (ie, no problems encountered) */
 static int
 removehomedir(const char *user, int uid, const char *dir)
@@ -243,7 +457,7 @@
 
 	(void) seteuid(uid);
 	/* we add the "|| true" to keep asystem() quiet if there is a non-zero exit status. */
-	(void) asystem("%s -rf %s > /dev/null 2>&1 || true", RM, dir);
+	(void) asystem("%s -rf %s > /dev/null 2>&1 || true", RM, quote(dir));
 	(void) seteuid(0);
 	if (rmdir(dir) < 0) {
 		warnx("Unable to remove all files in `%s'\n", dir);
@@ -386,10 +600,11 @@
 		warnx("No \"dot\" initialisation files found");
 	} else {
 		(void) asystem("cd %s; %s -rw -pe %s . %s", 
-				skeldir, PAX, (verbose) ? "-v" : "", dir);
+				quote(skeldir), PAX, (verbose) ? "-v" : "",
+			        quote(dir));
 	}
-	(void) asystem("%s -R -h %d:%d %s", CHOWN, uid, gid, dir);
-	(void) asystem("%s -R u+w %s", CHMOD, dir);
+	(void) asystem("%s -R -h %d:%d %s", CHOWN, uid, gid, quote(dir));
+	(void) asystem("%s -R u+w %s", CHMOD, quote(dir));
 	return n;
 }
 
@@ -407,6 +622,7 @@
 
 	if (getgrnam(group) != NULL) {
 		warnx("group `%s' already exists", group);
+		errno=0;
 		return 0;
 	}
 	if ((from = fopen(_PATH_GROUP, "r")) == NULL) {
@@ -612,18 +828,51 @@
 	return 1;
 }
 
-/* return 1 if `login' is a valid login name */
+/* return 1 if `login' is a valid login name, print warning
+ * and return 0 else */
 static int
-valid_login(char *login)
+validate_login(char *login)
 {
 	char	*cp;
+	int	valid;
+	int	allupper = 1;
+	int	letterfirst = 0;
+	int	strangechar = 0;
 
 	for (cp = login ; *cp ; cp++) {
+		/* Check for strange character */
 		if (!isalnum(*cp) && *cp != '.' && *cp != '_' && *cp != '-') {
-			return 0;
+			strangechar = 1;
 		}
+
+		/* Check for all upper case chars */
+		if (isalpha(*cp) && islower(*cp)) {
+			allupper = 0;
+		}
 	}
-	return 1;
+
+
+	/* Check if first character is a letter */
+	if (!isalpha(login[0]))
+		letterfirst = 0;
+
+	/* Print warnings if needed, and determine return code */
+	valid = 1;
+	
+	if (!letterfirst) {
+		valid = 0;
+		warnx("Warning: login name should begin with an alphabetic character");
+	}
+	if (allupper) {
+		valid = 0;
+		warnx("Warning: login name should have at least one lower case character");
+	}
+	if (strangechar) {
+		valid = 0;
+		warnx("Warning: login name consist of alphanumeric, '.', '_' and '-'");
+	}
+
+	return valid;
 }
 
 /* return 1 if `group' is a valid group name */
@@ -854,9 +1103,8 @@
 	int		cc;
 	int		i;
 
-	if (!valid_login(login)) {
-		errx(EXIT_FAILURE, "`%s' is not a valid login name", login);
-	}
+	validate_login(login);
+	
 	if ((masterfd = open(_PATH_MASTERPASSWD, O_RDONLY)) < 0) {
 		err(EXIT_FAILURE, "can't open `%s'", _PATH_MASTERPASSWD);
 	}
@@ -971,7 +1219,7 @@
 			(void) pw_abort();
 			errx(EXIT_FAILURE, "home directory `%s' already exists", home);
 		} else {
-			if (asystem("%s -p %s", MKDIR, home) != 0) {
+			if (asystem("%s -p %s", MKDIR, quote(home)) != 0) {
 				(void) close(ptmpfd);
 				(void) pw_abort();
 				err(EXIT_FAILURE, "can't mkdir `%s'", home);
@@ -1013,9 +1261,8 @@
 	int		masterfd;
 	int		ptmpfd;
 
-	if (!valid_login(newlogin)) {
-		errx(EXIT_FAILURE, "`%s' is not a valid login name", login);
-	}
+	validate_login(newlogin);
+	
 	if ((pwp = getpwnam(login)) == NULL) {
 		errx(EXIT_FAILURE, "No such user `%s'", login);
 	}
@@ -1144,7 +1391,7 @@
 	}
 	if (up != NULL) {
 		if ((up->u_flags & F_MKDIR) &&
-		    asystem("%s %s %s", MV, homedir, pwp->pw_dir) != 0) {
+		    asystem("%s %s %s", MV, quote(homedir), quote(pwp->pw_dir)) != 0) {
 			(void) close(ptmpfd);
 			(void) pw_abort();
 			err(EXIT_FAILURE, "can't move `%s' to `%s'",
Index: useradd.8
===================================================================
RCS file: /cvsroot/basesrc/usr.sbin/user/useradd.8,v
retrieving revision 1.5.4.1
diff -u -r1.5.4.1 useradd.8
--- useradd.8	2000/10/20 20:00:33	1.5.4.1
+++ useradd.8	2001/11/23 03:11:21
@@ -244,6 +244,13 @@
 .Ed
 .It Fl v
 enables verbose mode - explain the commands as they are executed.
+.It Ar user
+The login name of the user to add. Login names are recommended to
+contain only alphanumeric characters, ".", "_" and "-", a warning is
+printed else. Using other characters is supported by
+.Nm "" ,
+but may lead to unexpected behaviour in
+random applications. 
 .El
 .Pp
 The
Index: userdel.8
===================================================================
RCS file: /cvsroot/basesrc/usr.sbin/user/userdel.8,v
retrieving revision 1.5.4.1
diff -u -r1.5.4.1 userdel.8
--- userdel.8	2000/10/20 20:00:33	1.5.4.1
+++ userdel.8	2001/11/23 03:11:21
@@ -97,6 +97,13 @@
 and any files and other entries in them.
 .It Fl v
 perform any actions in a verbose manner.
+.It Ar user
+The login name of the user to add. Login names are recommended to
+contain only alphanumeric characters, ".", "_" and "-", a warning is
+printed else. Using other characters is supported by
+.Nm "" ,
+but may lead to unexpected behaviour in
+random applications. 
 .El
 .Pp
 The
Index: usermod.8
===================================================================
RCS file: /cvsroot/basesrc/usr.sbin/user/usermod.8,v
retrieving revision 1.4.4.3
diff -u -r1.4.4.3 usermod.8
--- usermod.8	2001/02/26 15:16:09	1.4.4.3
+++ usermod.8	2001/11/23 03:11:21
@@ -176,6 +176,13 @@
 .Ed
 .It Fl v
 enables verbose mode - explain the commands as they are executed.
+.It Ar user
+The login name of the user to add. Login names are recommended to
+contain only alphanumeric characters, ".", "_" and "-", a warning is
+printed else. Using other characters is supported by
+.Nm "" ,
+but may lead to unexpected behaviour in
+random applications. 
 .El
 .Pp
 The

-- 
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