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/*
* Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1985 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
#include "lint.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <stdio.h>
#include <limits.h>
#include <stdlib.h>
#include <sys/file.h>
#include "libc.h"
#include <unistd.h>
#define SHELLS "/etc/shells"
/*
* Do not add local shells here. They should be added in /etc/shells
*
* Do not add restricted shells:
* Shells returned by getusershell traditionally allow:
* - users to change away from (i.e., if you have an rksh in
* getusershell(), then users can change their shell to ksh)
* - by default, ftp in is allowed only for shells returned by
* getusershell(); since FTP has no restrictions on directory
* movement, adding rksh to getusershell() would defeat that
* protection.
*/
const char *okshells[] = {
"/usr/bin/sh",
"/usr/bin/csh",
"/usr/bin/ksh",
"/usr/bin/ksh93",
"/usr/bin/jsh",
"/bin/sh",
"/bin/csh",
"/bin/ksh",
"/bin/ksh93",
"/bin/jsh",
"/sbin/sh",
"/sbin/jsh",
"/usr/bin/pfsh",
"/usr/bin/pfcsh",
"/usr/bin/pfksh",
"/usr/bin/pfksh93",
"/usr/bin/bash",
"/usr/bin/tcsh",
"/usr/bin/zsh",
"/usr/bin/pfbash",
"/usr/bin/pftcsh",
"/usr/bin/pfzsh",
"/bin/pfsh",
"/bin/pfcsh",
"/bin/pfksh",
"/bin/pfksh93",
"/bin/bash",
"/bin/tcsh",
"/bin/zsh",
"/bin/pfbash",
"/bin/pftcsh",
"/bin/pfzsh",
"/usr/xpg4/bin/sh",
"/usr/xpg4/bin/pfsh",
"/sbin/pfsh",
"/usr/sfw/bin/zsh",
NULL
};
static char **shells, *strings;
static char **curshell;
static char **initshells(void);
/*
* Get a list of shells from SHELLS, if it exists.
*/
char *
getusershell(void)
{
char *ret;
if (curshell == NULL)
curshell = initshells();
ret = *curshell;
if (ret != NULL)
curshell++;
return (ret);
}
void
endusershell(void)
{
if (shells != NULL)
(void) free((char *)shells);
shells = NULL;
if (strings != NULL)
(void) free(strings);
strings = NULL;
curshell = NULL;
}
void
setusershell(void)
{
curshell = initshells();
}
static char **
initshells(void)
{
char **sp, *cp;
FILE *fp;
struct stat statb;
if (shells != NULL)
(void) free((char *)shells);
shells = NULL;
if (strings != NULL)
(void) free(strings);
strings = NULL;
if ((fp = fopen(SHELLS, "rF")) == (FILE *)0)
return ((char **)okshells);
/*
* The +1 in the malloc() below is needed to handle the final
* fgets() NULL terminator. From fgets(3S):
*
* char *fgets(char *s, int n, FILE *stream);
*
* The fgets() function reads characters from the stream into
* the array pointed to by s, until n-1 characters are read, or
* a newline character is read and transferred to s, or an end-
* of-file condition is encountered. The string is then termi-
* nated with a null character.
*/
if ((fstat(fileno(fp), &statb) == -1) || (statb.st_size > LONG_MAX) ||
((strings = malloc((size_t)statb.st_size + 1)) == NULL)) {
(void) fclose(fp);
return ((char **)okshells);
}
shells = calloc((size_t)statb.st_size / 3, sizeof (char *));
if (shells == NULL) {
(void) fclose(fp);
(void) free(strings);
strings = NULL;
return ((char **)okshells);
}
sp = shells;
cp = strings;
while (fgets(cp, MAXPATHLEN + 1, fp) != NULL) {
while (*cp != '#' && *cp != '/' && *cp != '\0')
cp++;
if (*cp == '#' || *cp == '\0')
continue;
*sp++ = cp;
while (!isspace(*cp) && *cp != '#' && *cp != '\0')
cp++;
*cp++ = '\0';
}
*sp = (char *)0;
(void) fclose(fp);
return (shells);
}
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