gnupg/common/exechelp-w32.c

780 lines
22 KiB
C

/* exechelp-w32.c - Fork and exec helpers for W32.
* Copyright (C) 2004, 2007, 2008, 2009,
* 2010 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* GnuPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* GnuPG is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#if !defined(HAVE_W32_SYSTEM) || defined (HAVE_W32CE_SYSTEM)
#error This code is only used on W32.
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#ifdef HAVE_SIGNAL_H
# include <signal.h>
#endif
#include <unistd.h>
#include <fcntl.h>
#ifdef WITHOUT_GNU_PTH /* Give the Makefile a chance to build without Pth. */
#undef HAVE_PTH
#undef USE_GNU_PTH
#endif
#ifdef USE_GNU_PTH
#include <pth.h>
#endif
#ifdef HAVE_STAT
# include <sys/stat.h>
#endif
#include "util.h"
#include "i18n.h"
#include "sysutils.h"
#include "exechelp.h"
/* Define to 1 do enable debugging. */
#define DEBUG_W32_SPAWN 1
/* It seems Vista doesn't grok X_OK and so fails access() tests.
Previous versions interpreted X_OK as F_OK anyway, so we'll just
use F_OK directly. */
#undef X_OK
#define X_OK F_OK
/* We assume that a HANDLE can be represented by an int which should
be true for all i386 systems (HANDLE is defined as void *) and
these are the only systems for which Windows is available. Further
we assume that -1 denotes an invalid handle. */
# define fd_to_handle(a) ((HANDLE)(a))
# define handle_to_fd(a) ((int)(a))
# define pid_to_handle(a) ((HANDLE)(a))
# define handle_to_pid(a) ((int)(a))
/* Return the maximum number of currently allowed open file
descriptors. Only useful on POSIX systems but returns a value on
other systems too. */
int
get_max_fds (void)
{
int max_fds = -1;
#ifdef OPEN_MAX
if (max_fds == -1)
max_fds = OPEN_MAX;
#endif
if (max_fds == -1)
max_fds = 256; /* Arbitrary limit. */
return max_fds;
}
/* Close all file descriptors starting with descriptor FIRST. If
EXCEPT is not NULL, it is expected to be a list of file descriptors
which shall not be closed. This list shall be sorted in ascending
order with the end marked by -1. */
void
close_all_fds (int first, int *except)
{
int max_fd = get_max_fds ();
int fd, i, except_start;
if (except)
{
except_start = 0;
for (fd=first; fd < max_fd; fd++)
{
for (i=except_start; except[i] != -1; i++)
{
if (except[i] == fd)
{
/* If we found the descriptor in the exception list
we can start the next compare run at the next
index because the exception list is ordered. */
except_start = i + 1;
break;
}
}
if (except[i] == -1)
close (fd);
}
}
else
{
for (fd=first; fd < max_fd; fd++)
close (fd);
}
gpg_err_set_errno (0);
}
/* Returns an array with all currently open file descriptors. The end
of the array is marked by -1. The caller needs to release this
array using the *standard free* and not with xfree. This allow the
use of this fucntion right at startup even before libgcrypt has
been initialized. Returns NULL on error and sets ERRNO
accordingly. */
int *
get_all_open_fds (void)
{
int *array;
size_t narray;
int fd, max_fd, idx;
#ifndef HAVE_STAT
array = calloc (1, sizeof *array);
if (array)
array[0] = -1;
#else /*HAVE_STAT*/
struct stat statbuf;
max_fd = get_max_fds ();
narray = 32; /* If you change this change also t-exechelp.c. */
array = calloc (narray, sizeof *array);
if (!array)
return NULL;
/* Note: The list we return is ordered. */
for (idx=0, fd=0; fd < max_fd; fd++)
if (!(fstat (fd, &statbuf) == -1 && errno == EBADF))
{
if (idx+1 >= narray)
{
int *tmp;
narray += (narray < 256)? 32:256;
tmp = realloc (array, narray * sizeof *array);
if (!tmp)
{
free (array);
return NULL;
}
array = tmp;
}
array[idx++] = fd;
}
array[idx] = -1;
#endif /*HAVE_STAT*/
return array;
}
/* Helper function to build_w32_commandline. */
static char *
build_w32_commandline_copy (char *buffer, const char *string)
{
char *p = buffer;
const char *s;
if (!*string) /* Empty string. */
p = stpcpy (p, "\"\"");
else if (strpbrk (string, " \t\n\v\f\""))
{
/* Need to do some kind of quoting. */
p = stpcpy (p, "\"");
for (s=string; *s; s++)
{
*p++ = *s;
if (*s == '\"')
*p++ = *s;
}
*p++ = '\"';
*p = 0;
}
else
p = stpcpy (p, string);
return p;
}
/* Build a command line for use with W32's CreateProcess. On success
CMDLINE gets the address of a newly allocated string. */
static gpg_error_t
build_w32_commandline (const char *pgmname, const char * const *argv,
char **cmdline)
{
int i, n;
const char *s;
char *buf, *p;
*cmdline = NULL;
n = 0;
s = pgmname;
n += strlen (s) + 1 + 2; /* (1 space, 2 quoting */
for (; *s; s++)
if (*s == '\"')
n++; /* Need to double inner quotes. */
for (i=0; (s=argv[i]); i++)
{
n += strlen (s) + 1 + 2; /* (1 space, 2 quoting */
for (; *s; s++)
if (*s == '\"')
n++; /* Need to double inner quotes. */
}
n++;
buf = p = xtrymalloc (n);
if (!buf)
return gpg_error_from_syserror ();
p = build_w32_commandline_copy (p, pgmname);
for (i=0; argv[i]; i++)
{
*p++ = ' ';
p = build_w32_commandline_copy (p, argv[i]);
}
*cmdline= buf;
return 0;
}
/* Create pipe where one end is inheritable: With an INHERIT_IDX of 0
the read end is inheritable, with 1 the write end is inheritable. */
static int
create_inheritable_pipe (int filedes[2], int inherit_idx)
{
HANDLE r, w, h;
SECURITY_ATTRIBUTES sec_attr;
memset (&sec_attr, 0, sizeof sec_attr );
sec_attr.nLength = sizeof sec_attr;
sec_attr.bInheritHandle = FALSE;
if (!CreatePipe (&r, &w, &sec_attr, 0))
return -1;
if (!DuplicateHandle (GetCurrentProcess(), inherit_idx? w : r,
GetCurrentProcess(), &h, 0,
TRUE, DUPLICATE_SAME_ACCESS ))
{
log_error ("DuplicateHandle failed: %s\n", w32_strerror (-1));
CloseHandle (r);
CloseHandle (w);
return -1;
}
if (inherit_idx)
{
CloseHandle (w);
w = h;
}
else
{
CloseHandle (r);
r = h;
}
filedes[0] = handle_to_fd (r);
filedes[1] = handle_to_fd (w);
return 0;
}
static HANDLE
w32_open_null (int for_write)
{
HANDLE hfile;
hfile = CreateFileW (L"nul",
for_write? GENERIC_WRITE : GENERIC_READ,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL, OPEN_EXISTING, 0, NULL);
if (hfile == INVALID_HANDLE_VALUE)
log_debug ("can't open `nul': %s\n", w32_strerror (-1));
return hfile;
}
static gpg_error_t
do_create_pipe (int filedes[2], int inherit_idx)
{
gpg_error_t err = 0;
int fds[2];
filedes[0] = filedes[1] = -1;
err = gpg_error (GPG_ERR_GENERAL);
if (!create_inheritable_pipe (fds, inherit_idx))
{
filedes[0] = _open_osfhandle (fds[0], 0);
if (filedes[0] == -1)
{
log_error ("failed to translate osfhandle %p\n", (void*)fds[0]);
CloseHandle (fd_to_handle (fds[1]));
}
else
{
filedes[1] = _open_osfhandle (fds[1], 1);
if (filedes[1] == -1)
{
log_error ("failed to translate osfhandle %p\n", (void*)fds[1]);
close (filedes[0]);
filedes[0] = -1;
CloseHandle (fd_to_handle (fds[1]));
}
else
err = 0;
}
}
return err;
}
/* Portable function to create a pipe. Under Windows the write end is
inheritable. */
gpg_error_t
gnupg_create_inbound_pipe (int filedes[2])
{
return do_create_pipe (filedes, 1);
}
/* Portable function to create a pipe. Under Windows the read end is
inheritable. */
gpg_error_t
gnupg_create_outbound_pipe (int filedes[2])
{
return do_create_pipe (filedes, 0);
}
/* Fork and exec the PGMNAME, see exechelp.h for details. */
gpg_error_t
gnupg_spawn_process (const char *pgmname, const char *argv[],
estream_t infile, estream_t outfile,
void (*preexec)(void), unsigned int flags,
estream_t *statusfile, pid_t *pid)
{
gpg_error_t err;
SECURITY_ATTRIBUTES sec_attr;
PROCESS_INFORMATION pi =
{
NULL, /* Returns process handle. */
0, /* Returns primary thread handle. */
0, /* Returns pid. */
0 /* Returns tid. */
};
STARTUPINFO si;
int cr_flags;
char *cmdline;
int fd, fdout, rp[2];
HANDLE nullhd[2];
int i;
(void)preexec;
/* Setup return values. */
*statusfile = NULL;
*pid = (pid_t)(-1);
if (infile)
{
es_fflush (infile);
es_rewind (infile);
fd = _get_osfhandle (es_fileno (infile));
}
else
fd = -1;
if (outfile)
fdout = _get_osfhandle (es_fileno (outfile));
else
fdout = -1;
if ( (infile && fd == -1) || (outfile && fdout == -1))
log_fatal ("no file descriptor for file passed to gnupg_spawn_process\n");
/* Prepare security attributes. */
memset (&sec_attr, 0, sizeof sec_attr );
sec_attr.nLength = sizeof sec_attr;
sec_attr.bInheritHandle = FALSE;
/* Build the command line. */
err = build_w32_commandline (pgmname, argv, &cmdline);
if (err)
return err;
/* Create a pipe. */
if (create_inheritable_pipe (rp, 1))
{
err = gpg_error (GPG_ERR_GENERAL);
log_error (_("error creating a pipe: %s\n"), gpg_strerror (err));
xfree (cmdline);
return err;
}
nullhd[0] = fd == -1? w32_open_null (0) : INVALID_HANDLE_VALUE;
nullhd[1] = fdout == -1? w32_open_null (1) : INVALID_HANDLE_VALUE;
/* Start the process. Note that we can't run the PREEXEC function
because this would change our own environment. */
memset (&si, 0, sizeof si);
si.cb = sizeof (si);
si.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
si.wShowWindow = DEBUG_W32_SPAWN? SW_SHOW : SW_MINIMIZE;
si.hStdInput = fd == -1? nullhd[0] : fd_to_handle (fd);
si.hStdOutput = fdout == -1? nullhd[1] : fd_to_handle (fdout);
si.hStdError = fd_to_handle (rp[1]);
cr_flags = (CREATE_DEFAULT_ERROR_MODE
| ((flags & 128)? DETACHED_PROCESS : 0)
| GetPriorityClass (GetCurrentProcess ())
| CREATE_SUSPENDED);
/* log_debug ("CreateProcess, path=`%s' cmdline=`%s'\n", pgmname, cmdline); */
if (!CreateProcess (pgmname, /* Program to start. */
cmdline, /* Command line arguments. */
&sec_attr, /* Process security attributes. */
&sec_attr, /* Thread security attributes. */
TRUE, /* Inherit handles. */
cr_flags, /* Creation flags. */
NULL, /* Environment. */
NULL, /* Use current drive/directory. */
&si, /* Startup information. */
&pi /* Returns process information. */
))
{
log_error ("CreateProcess failed: %s\n", w32_strerror (-1));
xfree (cmdline);
CloseHandle (fd_to_handle (rp[0]));
CloseHandle (fd_to_handle (rp[1]));
return gpg_error (GPG_ERR_GENERAL);
}
xfree (cmdline);
cmdline = NULL;
/* Close the inherited handles to /dev/null. */
for (i=0; i < DIM (nullhd); i++)
if (nullhd[i] != INVALID_HANDLE_VALUE)
CloseHandle (nullhd[i]);
/* Close the other end of the pipe. */
CloseHandle (fd_to_handle (rp[1]));
/* log_debug ("CreateProcess ready: hProcess=%p hThread=%p" */
/* " dwProcessID=%d dwThreadId=%d\n", */
/* pi.hProcess, pi.hThread, */
/* (int) pi.dwProcessId, (int) pi.dwThreadId); */
/* Fixme: For unknown reasons AllowSetForegroundWindow returns an
invalid argument error if we pass the correct processID to
it. As a workaround we use -1 (ASFW_ANY). */
if ( (flags & 64) )
gnupg_allow_set_foregound_window ((pid_t)(-1)/*pi.dwProcessId*/);
/* Process has been created suspended; resume it now. */
ResumeThread (pi.hThread);
CloseHandle (pi.hThread);
{
int x;
x = _open_osfhandle (rp[0], 0);
if (x == -1)
log_error ("failed to translate osfhandle %p\n", (void*)rp[0] );
else
*statusfile = es_fdopen (x, "r");
}
if (!*statusfile)
{
err = gpg_error_from_syserror ();
log_error (_("can't fdopen pipe for reading: %s\n"), gpg_strerror (err));
CloseHandle (pi.hProcess);
return err;
}
*pid = handle_to_pid (pi.hProcess);
return 0;
}
/* Simplified version of gnupg_spawn_process. This function forks and
then execs PGMNAME, while connecting INFD to stdin, OUTFD to stdout
and ERRFD to stderr (any of them may be -1 to connect them to
/dev/null). The arguments for the process are expected in the NULL
terminated array ARGV. The program name itself should not be
included there. Calling gnupg_wait_process is required.
Returns 0 on success or an error code. */
gpg_error_t
gnupg_spawn_process_fd (const char *pgmname, const char *argv[],
int infd, int outfd, int errfd, pid_t *pid)
{
gpg_error_t err;
SECURITY_ATTRIBUTES sec_attr;
PROCESS_INFORMATION pi = { NULL, 0, 0, 0 };
STARTUPINFO si;
char *cmdline;
int i;
HANDLE stdhd[3];
/* Setup return values. */
*pid = (pid_t)(-1);
/* Prepare security attributes. */
memset (&sec_attr, 0, sizeof sec_attr );
sec_attr.nLength = sizeof sec_attr;
sec_attr.bInheritHandle = FALSE;
/* Build the command line. */
err = build_w32_commandline (pgmname, argv, &cmdline);
if (err)
return err;
memset (&si, 0, sizeof si);
si.cb = sizeof (si);
si.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
si.wShowWindow = DEBUG_W32_SPAWN? SW_SHOW : SW_MINIMIZE;
stdhd[0] = infd == -1? w32_open_null (0) : INVALID_HANDLE_VALUE;
stdhd[1] = outfd == -1? w32_open_null (1) : INVALID_HANDLE_VALUE;
stdhd[2] = errfd == -1? w32_open_null (1) : INVALID_HANDLE_VALUE;
si.hStdInput = infd == -1? stdhd[0] : (void*)_get_osfhandle (infd);
si.hStdOutput = outfd == -1? stdhd[1] : (void*)_get_osfhandle (outfd);
si.hStdError = errfd == -1? stdhd[2] : (void*)_get_osfhandle (errfd);
/* log_debug ("CreateProcess, path=`%s' cmdline=`%s'\n", pgmname, cmdline); */
if (!CreateProcess (pgmname, /* Program to start. */
cmdline, /* Command line arguments. */
&sec_attr, /* Process security attributes. */
&sec_attr, /* Thread security attributes. */
TRUE, /* Inherit handles. */
(CREATE_DEFAULT_ERROR_MODE
| GetPriorityClass (GetCurrentProcess ())
| CREATE_SUSPENDED | DETACHED_PROCESS),
NULL, /* Environment. */
NULL, /* Use current drive/directory. */
&si, /* Startup information. */
&pi /* Returns process information. */
))
{
log_error ("CreateProcess failed: %s\n", w32_strerror (-1));
err = gpg_error (GPG_ERR_GENERAL);
}
else
err = 0;
xfree (cmdline);
for (i=0; i < 3; i++)
if (stdhd[i] != INVALID_HANDLE_VALUE)
CloseHandle (stdhd[i]);
if (err)
return err;
/* log_debug ("CreateProcess ready: hProcess=%p hThread=%p" */
/* " dwProcessID=%d dwThreadId=%d\n", */
/* pi.hProcess, pi.hThread, */
/* (int) pi.dwProcessId, (int) pi.dwThreadId); */
/* Process has been created suspended; resume it now. */
ResumeThread (pi.hThread);
CloseHandle (pi.hThread);
*pid = handle_to_pid (pi.hProcess);
return 0;
}
/* See exechelp.h for a description. */
gpg_error_t
gnupg_wait_process (const char *pgmname, pid_t pid, int hang, int *r_exitcode)
{
gpg_err_code_t ec;
HANDLE proc = fd_to_handle (pid);
int code;
DWORD exc;
if (r_exitcode)
*r_exitcode = -1;
if (pid == (pid_t)(-1))
return gpg_error (GPG_ERR_INV_VALUE);
/* FIXME: We should do a pth_waitpid here. However this has not yet
been implemented. A special W32 pth system call would even be
better. */
code = WaitForSingleObject (proc, hang? INFINITE : 0);
switch (code)
{
case WAIT_TIMEOUT:
ec = GPG_ERR_TIMEOUT;
break;
case WAIT_FAILED:
log_error (_("waiting for process %d to terminate failed: %s\n"),
(int)pid, w32_strerror (-1));
ec = GPG_ERR_GENERAL;
break;
case WAIT_OBJECT_0:
if (!GetExitCodeProcess (proc, &exc))
{
log_error (_("error getting exit code of process %d: %s\n"),
(int)pid, w32_strerror (-1) );
ec = GPG_ERR_GENERAL;
}
else if (exc)
{
log_error (_("error running `%s': exit status %d\n"),
pgmname, (int)exc );
if (r_exitcode)
*r_exitcode = (int)exc;
ec = GPG_ERR_GENERAL;
}
else
{
if (r_exitcode)
*r_exitcode = 0;
ec = 0;
}
break;
default:
log_error ("WaitForSingleObject returned unexpected "
"code %d for pid %d\n", code, (int)pid );
ec = GPG_ERR_GENERAL;
break;
}
return gpg_err_make (GPG_ERR_SOURCE_DEFAULT, ec);
}
void
gnupg_release_process (pid_t pid)
{
if (pid != (pid_t)INVALID_HANDLE_VALUE)
{
HANDLE process = (HANDLE)pid;
CloseHandle (process);
}
}
/* Spawn a new process and immediatley detach from it. The name of
the program to exec is PGMNAME and its arguments are in ARGV (the
programname is automatically passed as first argument).
Environment strings in ENVP are set. An error is returned if
pgmname is not executable; to make this work it is necessary to
provide an absolute file name. All standard file descriptors are
connected to /dev/null. */
gpg_error_t
gnupg_spawn_process_detached (const char *pgmname, const char *argv[],
const char *envp[] )
{
gpg_error_t err;
SECURITY_ATTRIBUTES sec_attr;
PROCESS_INFORMATION pi =
{
NULL, /* Returns process handle. */
0, /* Returns primary thread handle. */
0, /* Returns pid. */
0 /* Returns tid. */
};
STARTUPINFO si;
int cr_flags;
char *cmdline;
/* FIXME: We don't make use of ENVP yet. It is currently only used
to pass the GPG_AGENT_INFO variable to gpg-agent. As the default
on windows is to use a standard socket, this does not really
matter. */
(void)envp;
if (access (pgmname, X_OK))
return gpg_error_from_syserror ();
/* Prepare security attributes. */
memset (&sec_attr, 0, sizeof sec_attr );
sec_attr.nLength = sizeof sec_attr;
sec_attr.bInheritHandle = FALSE;
/* Build the command line. */
err = build_w32_commandline (pgmname, argv, &cmdline);
if (err)
return err;
/* Start the process. */
memset (&si, 0, sizeof si);
si.cb = sizeof (si);
si.dwFlags = STARTF_USESHOWWINDOW;
si.wShowWindow = DEBUG_W32_SPAWN? SW_SHOW : SW_MINIMIZE;
cr_flags = (CREATE_DEFAULT_ERROR_MODE
| GetPriorityClass (GetCurrentProcess ())
| CREATE_NEW_PROCESS_GROUP
| DETACHED_PROCESS);
/* log_debug ("CreateProcess(detached), path=`%s' cmdline=`%s'\n", */
/* pgmname, cmdline); */
if (!CreateProcess (pgmname, /* Program to start. */
cmdline, /* Command line arguments. */
&sec_attr, /* Process security attributes. */
&sec_attr, /* Thread security attributes. */
FALSE, /* Inherit handles. */
cr_flags, /* Creation flags. */
NULL, /* Environment. */
NULL, /* Use current drive/directory. */
&si, /* Startup information. */
&pi /* Returns process information. */
))
{
log_error ("CreateProcess(detached) failed: %s\n", w32_strerror (-1));
xfree (cmdline);
return gpg_error (GPG_ERR_GENERAL);
}
xfree (cmdline);
cmdline = NULL;
/* log_debug ("CreateProcess(detached) ready: hProcess=%p hThread=%p" */
/* " dwProcessID=%d dwThreadId=%d\n", */
/* pi.hProcess, pi.hThread, */
/* (int) pi.dwProcessId, (int) pi.dwThreadId); */
CloseHandle (pi.hThread);
return 0;
}
/* Kill a process; that is send an appropriate signal to the process.
gnupg_wait_process must be called to actually remove the process
from the system. An invalid PID is ignored. */
void
gnupg_kill_process (pid_t pid)
{
if (pid != (pid_t) INVALID_HANDLE_VALUE)
{
HANDLE process = (HANDLE) pid;
/* Arbitrary error code. */
TerminateProcess (process, 1);
}
}