On Thursday 19 July 2007 22:37:43 Alexander Shishkin wrote:
> On 7/19/07, Tito <[EMAIL PROTECTED]> wrote:
> > Hi,
> Hi,
>
> > attached you will find a drop in replacement
> > for chpasswd.c with some more busyboxification
> > (use of getopt32 and syslogging capabilities of
> > bb_*_msg_* functions) and some things it seems to me that
> > need to be fixed (this could be done to me being in hurry
> > and not understanding you code... in this case ignore it).
> > This code is only compile tested and needs more care and love. ;-)
> Thanks for pointing these things out! I've done some more tweaking on
> the applet. Attached please find an updated patch.
>
> Regards,
> --
> Alex
>
Hi,
would something like passwd USER PASSWORD work for you?
If yes, can you please test this modified version of passwd.
So we can avoid code duplication.
The non interactive mode is switched on with a config option.
Add this to loginutils/Config.in after config FEATURE_PASSWD_WEAK_CHECK.
---------------------------------
config FEATURE_NON_INTERACTIVE_PASSWD
bool "Allow passwords to be set non interactively (UNSAFE)"
default n
depends on PASSWD
help
With this option passwd will accept USER and PASSWD from
the command line and set them non interactively.
THIS IS UNSAFE!!!
------------------------------------
and use passwd.c as drop-in replacement.
(TODO the help text in usage.h needs to be fixed.)
This is only a little tested, hints, critics and improvements are welcome.
If this solution is not ok for you i'll give one more look at your patch.
Ciao,
Tito
/* vi: set sw=4 ts=4: */
/*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include <syslog.h>
static void nuke_str(char *str)
{
if (str) memset(str, 0, strlen(str));
}
static char* new_password(const struct passwd *pw, uid_t myuid, int algo
USE_FEATURE_NON_INTERACTIVE_PASSWD(, char *newp))
{
char salt[sizeof("$N$XXXXXXXX")]; /* "$N$XXXXXXXX" or "XX" */
char *orig = (char*)"";
SKIP_FEATURE_NON_INTERACTIVE_PASSWD(char *newp = NULL;)
char *cipher = NULL;
char *cp = NULL;
char *ret = NULL; /* failure so far */
USE_FEATURE_NON_INTERACTIVE_PASSWD(if (newp) goto non_interactive);
if (myuid && pw->pw_passwd[0]) {
orig = bb_askpass(0, "Old password:"); /* returns ptr to static */
if (!orig)
goto err_ret;
cipher = pw_encrypt(orig, pw->pw_passwd); /* returns ptr to static */
if (strcmp(cipher, pw->pw_passwd) != 0) {
syslog(LOG_WARNING, "incorrect password for '%s'",
pw->pw_name);
bb_do_delay(FAIL_DELAY);
puts("Incorrect password");
goto err_ret;
}
}
orig = xstrdup(orig); /* or else bb_askpass() will destroy it */
newp = bb_askpass(0, "New password:"); /* returns ptr to static */
if (!newp)
goto err_ret;
newp = xstrdup(newp); /* we are going to bb_askpass() again, so save it */
if (ENABLE_FEATURE_PASSWD_WEAK_CHECK
&& obscure(orig, newp, pw) && myuid)
goto err_ret; /* non-root is not allowed to have weak passwd */
cp = bb_askpass(0, "Retype password:");
if (!cp)
goto err_ret;
if (strcmp(cp, newp)) {
puts("Passwords don't match");
goto err_ret;
}
/*memset(salt, 0, sizeof(salt)); - why?*/
USE_FEATURE_NON_INTERACTIVE_PASSWD(non_interactive:)
crypt_make_salt(salt, 1); /* des */
if (algo) { /* MD5 */
strcpy(salt, "$1$");
crypt_make_salt(salt + 3, 4);
}
ret = xstrdup(pw_encrypt(newp, salt)); /* returns ptr to static */
/* whee, success! */
err_ret:
nuke_str(orig);
if (ENABLE_FEATURE_CLEAN_UP) free(orig);
nuke_str(newp);
if (ENABLE_FEATURE_CLEAN_UP) free(newp);
nuke_str(cipher);
nuke_str(cp);
return ret;
}
static int update_passwd(const char *filename, const char *username,
const char *new_pw)
{
struct stat sb;
struct flock lock;
FILE *old_fp;
FILE *new_fp;
char *new_name;
char *last_char;
unsigned user_len;
int old_fd;
int new_fd;
int i;
int ret = 1; /* failure */
logmode = LOGMODE_STDIO;
/* New passwd file, "/etc/passwd+" for now */
new_name = xasprintf("%s+", filename);
last_char = &new_name[strlen(new_name)-1];
username = xasprintf("%s:", username);
user_len = strlen(username);
old_fp = fopen(filename, "r+");
if (!old_fp)
goto free_mem;
old_fd = fileno(old_fp);
/* Try to create "/etc/passwd+". Wait if it exists. */
i = 30;
do {
// FIXME: on last iteration try w/o O_EXCL but with O_TRUNC?
new_fd = open(new_name, O_WRONLY|O_CREAT|O_EXCL,0600);
if (new_fd >= 0) goto created;
if (errno != EEXIST) break;
usleep(100000); /* 0.1 sec */
} while (--i);
bb_perror_msg("cannot create '%s'", new_name);
goto close_old_fp;
created:
if (!fstat(old_fd, &sb)) {
fchmod(new_fd, sb.st_mode & 0777); /* ignore errors */
fchown(new_fd, sb.st_uid, sb.st_gid);
}
new_fp = fdopen(new_fd, "w");
if (!new_fp) {
close(new_fd);
goto unlink_new;
}
/* Backup file is "/etc/passwd-" */
last_char[0] = '-';
/* Delete old one, create new as a hardlink to current */
i = (unlink(new_name) && errno != ENOENT);
if (i || link(filename, new_name))
bb_perror_msg("warning: cannot create backup copy '%s'", new_name);
last_char[0] = '+';
/* Lock the password file before updating */
lock.l_type = F_WRLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
if (fcntl(old_fd, F_SETLK, &lock) < 0)
bb_perror_msg("warning: cannot lock '%s'", filename);
lock.l_type = F_UNLCK;
/* Read current password file, write updated one */
while (1) {
char *line = xmalloc_fgets(old_fp);
if (!line) break; /* EOF/error */
if (strncmp(username, line, user_len) == 0) {
/* we have a match with "username:"... */
const char *cp = line + user_len;
/* now cp -> old passwd, skip it: */
cp = strchr(cp, ':');
if (!cp) cp = "";
/* now cp -> ':' after old passwd or -> "" */
fprintf(new_fp, "%s%s%s", username, new_pw, cp);
/* Erase password in memory */
} else
fputs(line, new_fp);
free(line);
}
fcntl(old_fd, F_SETLK, &lock);
/* We do want all of them to execute, thus | instead of || */
if ((ferror(old_fp) | fflush(new_fp) | fsync(new_fd) | fclose(new_fp))
|| rename(new_name, filename)
) {
/* At least one of those failed */
goto unlink_new;
}
ret = 0; /* whee, success! */
unlink_new:
if (ret) unlink(new_name);
close_old_fp:
fclose(old_fp);
free_mem:
if (ENABLE_FEATURE_CLEAN_UP) free(new_name);
if (ENABLE_FEATURE_CLEAN_UP) free((char*)username);
logmode = LOGMODE_BOTH;
return ret;
}
int passwd_main(int argc, char **argv);
int passwd_main(int argc, char **argv)
{
enum {
OPT_algo = 0x1, /* -a - password algorithm */
OPT_lock = 0x2, /* -l - lock account */
OPT_unlock = 0x4, /* -u - unlock account */
OPT_delete = 0x8, /* -d - delete password */
OPT_lud = 0xe,
STATE_ALGO_md5 = 0x10,
/*STATE_ALGO_des = 0x20, not needed yet */
};
unsigned opt;
const char *opt_a = "";
const char *filename;
char *myname;
char *name;
char *newp;
struct passwd *pw;
uid_t myuid;
struct rlimit rlimit_fsize;
char c;
#if ENABLE_FEATURE_SHADOWPASSWDS
/* Using _r function to avoid pulling in static buffers */
struct spwd spw;
struct spwd *result;
char buffer[256];
#endif
logmode = LOGMODE_BOTH;
openlog(applet_name, LOG_NOWAIT, LOG_AUTH);
opt = getopt32(argc, argv, "a:lud", &opt_a);
argc -= optind;
argv += optind;
if (strcasecmp(opt_a, "des") != 0) /* -a */
opt |= STATE_ALGO_md5;
//else
// opt |= STATE_ALGO_des;
myuid = getuid();
if ((opt & OPT_lud) && (!argc || myuid))
bb_show_usage();
myname = xstrdup(bb_getpwuid(NULL, myuid, -1));
name = argc ? argv[0] : myname;
if (ENABLE_FEATURE_NON_INTERACTIVE_PASSWD)
newp = (argc > 1) ? xstrdup(argv[1]) : NULL;
else
newp = NULL;
pw = getpwnam(name);
if (!pw) bb_error_msg_and_die("unknown user %s", name);
if (myuid && pw->pw_uid != myuid) {
/* LOGMODE_BOTH */
bb_error_msg_and_die("%s can't change password for %s", myname, name);
}
filename = bb_path_passwd_file;
#if ENABLE_FEATURE_SHADOWPASSWDS
if (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result)) {
/* LOGMODE_BOTH */
bb_error_msg("no record of %s in %s, using %s",
name, bb_path_shadow_file,
bb_path_passwd_file);
} else {
filename = bb_path_shadow_file;
pw->pw_passwd = spw.sp_pwdp;
}
#endif
/* Decide what the new password will be */
c = pw->pw_passwd[0] - '!';
if (!(opt & OPT_lud)) {
if (myuid && !c) { /* passwd starts with '!' */
/* LOGMODE_BOTH */
bb_error_msg_and_die("cannot change "
"locked password for %s", name);
}
printf("Changing password for %s\n", name);
newp = new_password(pw, myuid, opt & STATE_ALGO_md5 USE_FEATURE_NON_INTERACTIVE_PASSWD(, newp));
if (!newp) {
logmode = LOGMODE_STDIO;
bb_error_msg_and_die("password for %s is unchanged", name);
}
} else if (opt & OPT_lock) {
if (!c) goto skip; /* passwd starts with '!' */
newp = xasprintf("!%s", pw->pw_passwd);
} else if (opt & OPT_unlock) {
if (c) goto skip; /* not '!' */
newp = xstrdup(&pw->pw_passwd[1]);
} else if (opt & OPT_delete) {
newp = xstrdup("");
}
rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * 30000;
setrlimit(RLIMIT_FSIZE, &rlimit_fsize);
signal(SIGHUP, SIG_IGN);
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
umask(077);
xsetuid(0);
if (update_passwd(filename, name, newp) != 0) {
/* LOGMODE_BOTH */
bb_error_msg_and_die("cannot update password file %s",
filename);
}
/* LOGMODE_BOTH */
bb_info_msg("Password for %s changed by %s", name, myname);
if (ENABLE_FEATURE_CLEAN_UP) free(newp);
skip:
if (!newp) {
bb_error_msg_and_die("password for %s is already %slocked",
name, (opt & OPT_unlock) ? "un" : "");
}
if (ENABLE_FEATURE_CLEAN_UP) free(myname);
return 0;
}
_______________________________________________
busybox mailing list
[email protected]
http://busybox.net/cgi-bin/mailman/listinfo/busybox
