diff options
Diffstat (limited to 'login-utils/chsh.c')
| -rw-r--r-- | login-utils/chsh.c | 101 |
1 files changed, 77 insertions, 24 deletions
diff --git a/login-utils/chsh.c b/login-utils/chsh.c index 9ffd81b2f..3cafc966b 100644 --- a/login-utils/chsh.c +++ b/login-utils/chsh.c @@ -6,17 +6,27 @@ * modify it under the terms of the gnu general public license. * there is no warranty. * - * $Author: faith $ - * $Revision: 1.8 $ - * $Date: 1995/10/12 14:46:35 $ + * $Author: aebr $ + * $Revision: 1.16 $ + * $Date: 1997/07/06 00:12:08 $ * * Updated Thu Oct 12 09:33:15 1995 by faith@cs.unc.edu with security - * patches from Zefram <A.Main@dcs.warwick.ac.uk> + * patches from Zefram <A.Main@dcs.warwick.ac.uk> + * + * Updated Mon Jul 1 18:46:22 1996 by janl@math.uio.no with security + * suggestion from Zefram. Disallowing users with shells not in /etc/shells + * from changing their shell. + * + * Hacked by Peter Breitenlohner, peb@mppmu.mpg.de, + * to allow peaceful coexistence with yp: using the changes by + * Alvaro Martinez Echevarria, alvaro@enano.etsit.upm.es, from + * passwd.c (now moved to setpwnam.c). Oct 5, 96. * */ -static char rcsId[] = "$Version: $Id: chsh.c,v 1.8 1995/10/12 14:46:35 faith Exp $ $"; +static char rcsId[] = "$Version: $Id: chsh.c,v 1.16 1997/07/06 00:12:08 aebr Exp $ $"; +#define _XOPEN_SOURCE /* to get definition of crypt() */ #if 0 #define _POSIX_SOURCE 1 #endif @@ -30,6 +40,14 @@ static char rcsId[] = "$Version: $Id: chsh.c,v 1.8 1995/10/12 14:46:35 faith Exp #include <errno.h> #include <ctype.h> #include <getopt.h> +#include "../version.h" + +#if REQUIRE_PASSWORD && USE_PAM +#include <security/pam_appl.h> +#include <security/pam_misc.h> +#endif + +extern int is_local(char *); #undef P #if __STDC__ @@ -42,7 +60,10 @@ typedef unsigned char boolean; #define false 0 #define true 1 -static char *version_string = "chsh 0.9a beta"; +/* Only root is allowed to assign a luser a non-listed shell, by default */ +#define ONLY_LISTED_SHELLS 1 + + static char *whoami; static char buf[FILENAME_MAX]; @@ -70,6 +91,11 @@ int main (argc, argv) struct sinfo info; struct passwd *pw; extern int errno; +#if REQUIRE_PASSWORD && USE_PAM + pam_handle_t *pamh = NULL; + int retcode; + struct pam_conv conv = { misc_conv, NULL }; +#endif /* whoami is the program name for error messages */ whoami = argv[0]; @@ -96,21 +122,21 @@ int main (argc, argv) return (-1); } } + if (!(is_local(pw->pw_name))) { + fprintf (stderr, "%s: can only change local entries; use yp%s instead.\n +", + whoami, whoami); + exit(1); + } + oldshell = pw->pw_shell; if (!oldshell[0]) oldshell = "/bin/sh"; /* reality check */ -#if 0 - /* Require current shell to be in list. - This is not a reasonable expectation on - most Linux systems, and the error is - confusing. */ if (uid != 0 && (uid != pw->pw_uid || !get_shell_list(oldshell))) { -#else - if (uid != 0 && uid != pw->pw_uid) { -#endif errno = EACCES; - perror (whoami); + fprintf(stderr,"%s: Your shell is not in /etc/shells, shell change" + " denied\n",whoami); return (-1); } @@ -118,16 +144,43 @@ int main (argc, argv) printf( "Changing shell for %s.\n", pw->pw_name ); -#ifdef REQUIRE_PASSWORD +#if REQUIRE_PASSWORD +# if USE_PAM + if(uid != 0) { + if (pam_start("chsh", pw->pw_name, &conv, &pamh)) { + puts("Password error."); + exit(1); + } + if (pam_authenticate(pamh, 0)) { + puts("Password error."); + exit(1); + } + retcode = pam_acct_mgmt(pamh, 0); + if (retcode == PAM_AUTHTOKEN_REQD) { + retcode = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK); + } else if (retcode) { + puts("Password error."); + exit(1); + } + if (pam_setcred(pamh, 0)) { + puts("Password error."); + exit(1); + } + /* no need to establish a session; this isn't a session-oriented + * activity... */ + } +# else /* USE_PAM */ /* require password, unless root */ if(uid != 0 && pw->pw_passwd && pw->pw_passwd[0]) { pwdstr = getpass("Password: "); - if(strncmp(pw->pw_passwd, crypt(pwdstr, pw->pw_passwd), 13)) { + if(strncmp(pw->pw_passwd, + crypt(pwdstr, pw->pw_passwd), 13)) { puts("Incorrect password."); exit(1); } } -#endif +# endif /* USE_PAM */ +#endif /* REQUIRE_PASSWORD */ if (! shell) { shell = prompt ("New shell", oldshell); @@ -178,7 +231,7 @@ static void parse_argv (argc, argv, pinfo) case EOF: break; case 'v': - printf ("%s\n", version_string); + printf ("%s\n", util_linux_version); exit (0); case 'u': usage (stdout); @@ -246,7 +299,7 @@ static char *prompt (question, def_val) if (len <= 0) return NULL; ans[len] = 0; cp = (char *) xmalloc (len + 1); - strcpy (cp, buf); + strcpy (cp, ans); return cp; } @@ -287,17 +340,17 @@ static int check_shell (shell) #if ONLY_LISTED_SHELLS if (! get_shell_list (shell)) { if (!getuid()) - printf ("Warning: \"%s\" is not listed as a valid shell.\n", shell); + printf ("Warning: \"%s\" is not listed in /etc/shells\n", shell); else { - printf ("%s: \"%s\" is not listed as a valid shell.\n", + printf ("%s: \"%s\" is not listed in /etc/shells.\n", whoami, shell); - printf( "%s: use -l option to see list\n" ); + printf( "%s: use -l option to see list\n", whoami ); exit(1); } } #else if (! get_shell_list (shell)) { - printf ("Warning: \"%s\" is not listed as a valid shell.\n", shell); + printf ("Warning: \"%s\" is not listed in /etc/shells.\n", shell); printf( "Use %s -l to see list.\n", whoami ); } #endif |