newlib/winsup/cygwin/passwd.cc
Corinna Vinschen 7c4626ed08 * passwd.cc (getpass): Make check for closed stream more reliable.
Check if setting tty attributes worked and only revert to old state
	if so.
2012-07-09 12:57:03 +00:00

324 lines
7.8 KiB
C++

/* passwd.cc: getpwnam () and friends
Copyright 1996, 1997, 1998, 2001, 2002, 2003, 2007, 2008, 2009,
2010, 2011, 2012 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <stdlib.h>
#include <stdio.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "pinfo.h"
#include "cygheap.h"
#include "pwdgrp.h"
#include "shared_info.h"
/* Read /etc/passwd only once for better performance. This is done
on the first call that needs information from it. */
passwd *passwd_buf;
static pwdgrp pr (passwd_buf);
/* Parse /etc/passwd line into passwd structure. */
bool
pwdgrp::parse_passwd ()
{
passwd &res = (*passwd_buf)[curr_lines];
res.pw_name = next_str (':');
res.pw_passwd = next_str (':');
if (!next_num (res.pw_uid))
return false;
if (!next_num (res.pw_gid))
return false;
res.pw_comment = NULL;
res.pw_gecos = next_str (':');
res.pw_dir = next_str (':');
res.pw_shell = next_str (':');
return true;
}
/* Read in /etc/passwd and save contents in the password cache.
This sets pr to loaded or emulated so functions in this file can
tell that /etc/passwd has been read in or will be emulated. */
void
pwdgrp::read_passwd ()
{
load (L"\\etc\\passwd");
char strbuf[128] = "";
bool searchentry = true;
struct passwd *pw;
/* must be static */
static char NO_COPY pretty_ls[] = "????????:*:-1:-1:::";
add_line (pretty_ls);
cygsid tu = cygheap->user.sid ();
tu.string (strbuf);
if (!user_shared->cb || myself->uid == ILLEGAL_UID)
searchentry = !internal_getpwsid (tu);
if (searchentry
&& (!(pw = internal_getpwnam (cygheap->user.name ()))
|| !user_shared->cb
|| (myself->uid != ILLEGAL_UID
&& myself->uid != (__uid32_t) pw->pw_uid
&& !internal_getpwuid (myself->uid))))
{
static char linebuf[1024]; // must be static and
// should not be NO_COPY
snprintf (linebuf, sizeof (linebuf), "%s:*:%lu:%lu:,%s:%s:/bin/sh",
cygheap->user.name (),
(!user_shared->cb || myself->uid == ILLEGAL_UID)
? UNKNOWN_UID : myself->uid,
!user_shared->cb ? UNKNOWN_GID : myself->gid,
strbuf, getenv ("HOME") ?: "");
debug_printf ("Completing /etc/passwd: %s", linebuf);
add_line (linebuf);
}
}
struct passwd *
internal_getpwsid (cygpsid &sid)
{
struct passwd *pw;
char *ptr1, *ptr2, *endptr;
char sid_string[128] = {0,','};
pr.refresh (false);
if (sid.string (sid_string + 2))
{
endptr = strchr (sid_string + 2, 0) - 1;
for (int i = 0; i < pr.curr_lines; i++)
{
pw = passwd_buf + i;
if (pw->pw_dir > pw->pw_gecos + 8)
for (ptr1 = endptr, ptr2 = pw->pw_dir - 2;
*ptr1 == *ptr2; ptr2--)
if (!*--ptr1)
return pw;
}
}
return NULL;
}
struct passwd *
internal_getpwuid (__uid32_t uid, bool check)
{
pr.refresh (check);
for (int i = 0; i < pr.curr_lines; i++)
if (uid == (__uid32_t) passwd_buf[i].pw_uid)
return passwd_buf + i;
return NULL;
}
struct passwd *
internal_getpwnam (const char *name, bool check)
{
pr.refresh (check);
for (int i = 0; i < pr.curr_lines; i++)
/* on Windows NT user names are case-insensitive */
if (strcasematch (name, passwd_buf[i].pw_name))
return passwd_buf + i;
return NULL;
}
extern "C" struct passwd *
getpwuid32 (__uid32_t uid)
{
struct passwd *temppw = internal_getpwuid (uid, true);
pthread_testcancel ();
return temppw;
}
extern "C" struct passwd *
getpwuid (__uid16_t uid)
{
return getpwuid32 (uid16touid32 (uid));
}
extern "C" int
getpwuid_r32 (__uid32_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
{
*result = NULL;
if (!pwd || !buffer)
return ERANGE;
struct passwd *temppw = internal_getpwuid (uid, true);
pthread_testcancel ();
if (!temppw)
return 0;
/* check needed buffer size. */
size_t needsize = strlen (temppw->pw_name) + strlen (temppw->pw_passwd)
+ strlen (temppw->pw_gecos) + strlen (temppw->pw_dir)
+ strlen (temppw->pw_shell) + 5;
if (needsize > bufsize)
return ERANGE;
/* make a copy of temppw */
*result = pwd;
pwd->pw_uid = temppw->pw_uid;
pwd->pw_gid = temppw->pw_gid;
buffer = stpcpy (pwd->pw_name = buffer, temppw->pw_name);
buffer = stpcpy (pwd->pw_passwd = buffer + 1, temppw->pw_passwd);
buffer = stpcpy (pwd->pw_gecos = buffer + 1, temppw->pw_gecos);
buffer = stpcpy (pwd->pw_dir = buffer + 1, temppw->pw_dir);
stpcpy (pwd->pw_shell = buffer + 1, temppw->pw_shell);
pwd->pw_comment = NULL;
return 0;
}
extern "C" int
getpwuid_r (__uid16_t uid, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
{
return getpwuid_r32 (uid16touid32 (uid), pwd, buffer, bufsize, result);
}
extern "C" struct passwd *
getpwnam (const char *name)
{
struct passwd *temppw = internal_getpwnam (name, true);
pthread_testcancel ();
return temppw;
}
/* the max size buffer we can expect to
* use is returned via sysconf with _SC_GETPW_R_SIZE_MAX.
* This may need updating! - Rob Collins April 2001.
*/
extern "C" int
getpwnam_r (const char *nam, struct passwd *pwd, char *buffer, size_t bufsize, struct passwd **result)
{
*result = NULL;
if (!pwd || !buffer || !nam)
return ERANGE;
struct passwd *temppw = internal_getpwnam (nam, true);
pthread_testcancel ();
if (!temppw)
return 0;
/* check needed buffer size. */
size_t needsize = strlen (temppw->pw_name) + strlen (temppw->pw_passwd)
+ strlen (temppw->pw_gecos) + strlen (temppw->pw_dir)
+ strlen (temppw->pw_shell) + 5;
if (needsize > bufsize)
return ERANGE;
/* make a copy of temppw */
*result = pwd;
pwd->pw_uid = temppw->pw_uid;
pwd->pw_gid = temppw->pw_gid;
buffer = stpcpy (pwd->pw_name = buffer, temppw->pw_name);
buffer = stpcpy (pwd->pw_passwd = buffer + 1, temppw->pw_passwd);
buffer = stpcpy (pwd->pw_gecos = buffer + 1, temppw->pw_gecos);
buffer = stpcpy (pwd->pw_dir = buffer + 1, temppw->pw_dir);
stpcpy (pwd->pw_shell = buffer + 1, temppw->pw_shell);
pwd->pw_comment = NULL;
return 0;
}
extern "C" struct passwd *
getpwent (void)
{
if (_my_tls.locals.pw_pos == 0)
pr.refresh (true);
if (_my_tls.locals.pw_pos < pr.curr_lines)
return passwd_buf + _my_tls.locals.pw_pos++;
return NULL;
}
extern "C" struct passwd *
getpwduid (__uid16_t)
{
return NULL;
}
extern "C" void
setpwent (void)
{
_my_tls.locals.pw_pos = 0;
}
extern "C" void
endpwent (void)
{
_my_tls.locals.pw_pos = 0;
}
extern "C" int
setpassent ()
{
return 0;
}
static void
_getpass_close_fd (void *arg)
{
if (arg)
fclose ((FILE *) arg);
}
extern "C" char *
getpass (const char * prompt)
{
char *pass = _my_tls.locals.pass;
struct termios ti, newti;
bool tc_set = false;
/* Try to use controlling tty in the first place. Use stdin and stderr
only as fallback. */
FILE *in = stdin, *err = stderr;
FILE *tty = fopen ("/dev/tty", "w+b");
pthread_cleanup_push (_getpass_close_fd, tty);
if (tty)
{
/* Set close-on-exec for obvious reasons. */
fcntl (fileno (tty), F_SETFD, fcntl (fileno (tty), F_GETFD) | FD_CLOEXEC);
in = err = tty;
}
/* Make sure to notice if stdin is closed. */
if (fileno (in) >= 0)
{
flockfile (in);
/* Change tty attributes if possible. */
if (!tcgetattr (fileno (in), &ti))
{
newti = ti;
newti.c_lflag &= ~(ECHO | ISIG); /* No echo, no signal handling. */
if (!tcsetattr (fileno (in), TCSANOW, &newti))
tc_set = true;
}
fputs (prompt, err);
fflush (err);
fgets (pass, _PASSWORD_LEN, in);
fprintf (err, "\n");
if (tc_set)
tcsetattr (fileno (in), TCSANOW, &ti);
funlockfile (in);
char *crlf = strpbrk (pass, "\r\n");
if (crlf)
*crlf = '\0';
}
pthread_cleanup_pop (1);
return pass;
}