[gssapi-openssh.git] / openssh / openbsd-compat / bsd-cygwin_util.c

/*
 * cygwin_util.c
 *
 * Copyright (c) 2000, 2001, Corinna Vinschen <vinschen@cygnus.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Created: Sat Sep 02 12:17:00 2000 cv
 *
 * This file contains functions for forcing opened file descriptors to
 * binary mode on Windows systems.
 */

#include "includes.h"

RCSID("$Id$");

#ifdef HAVE_CYGWIN

#include <fcntl.h>
#include <stdlib.h>
#include <sys/utsname.h>
#include <sys/vfs.h>
#include <windows.h>
#define is_winnt       (GetVersion() < 0x80000000)

#define ntsec_on(c)	((c) && strstr((c),"ntsec") && !strstr((c),"nontsec"))
#define ntsec_off(c)	((c) && strstr((c),"nontsec"))
#define ntea_on(c)	((c) && strstr((c),"ntea") && !strstr((c),"nontea"))

#if defined(open) && open == binary_open
# undef open
#endif
#if defined(pipe) && open == binary_pipe
# undef pipe
#endif

int binary_open(const char *filename, int flags, ...)
{
	va_list ap;
	mode_t mode;
	
	va_start(ap, flags);
	mode = va_arg(ap, mode_t);
	va_end(ap);
	return open(filename, flags | O_BINARY, mode);
}

int binary_pipe(int fd[2])
{
	int ret = pipe(fd);

	if (!ret) {
		setmode (fd[0], O_BINARY);
		setmode (fd[1], O_BINARY);
	}
	return ret;
}

#define HAS_CREATE_TOKEN 1
#define HAS_NTSEC_BY_DEFAULT 2

static int has_capability(int what)
{
	/* has_capability() basically calls uname() and checks if
	   specific capabilities of Cygwin can be evaluated from that.
	   This simplifies the calling functions which only have to ask
	   for a capability using has_capability() instead of having
	   to figure that out by themselves. */
	static int inited;
	static int has_create_token;
	static int has_ntsec_by_default;

	if (!inited) {
		struct utsname uts;
		char *c;
		
		if (!uname(&uts)) {
			int major_high = 0;
			int major_low = 0;
			int minor = 0;
			int api_major_version = 0;
			int api_minor_version = 0;
			char *c;

			sscanf(uts.release, "%d.%d.%d", &major_high,
			       &major_low, &minor);
			c = strchr(uts.release, '(');
			if (c)
				sscanf(c + 1, "%d.%d", &api_major_version,
				       &api_minor_version);
			if (major_high > 1 ||
			    (major_high == 1 && (major_low > 3 ||
			     (major_low == 3 && minor >= 2))))
				has_create_token = 1;
			if (api_major_version > 0 || api_minor_version >= 56)
				has_ntsec_by_default = 1;
			inited = 1;
		}
	}
	switch (what) {
	case HAS_CREATE_TOKEN:
		return has_create_token;
	case HAS_NTSEC_BY_DEFAULT:
		return has_ntsec_by_default;
	}
	return 0;
}

int check_nt_auth(int pwd_authenticated, struct passwd *pw)
{
	/*
	* The only authentication which is able to change the user
	* context on NT systems is the password authentication. So
	* we deny all requsts for changing the user context if another
	* authentication method is used.
	*
	* This doesn't apply to Cygwin versions >= 1.3.2 anymore which
	* uses the undocumented NtCreateToken() call to create a user
	* token if the process has the appropriate privileges and if
	* CYGWIN ntsec setting is on.
	*/
	static int has_create_token = -1;

	if (pw == NULL)
		return 0;
	if (is_winnt) {
		if (has_create_token < 0) {
			char *cygwin = getenv("CYGWIN");

			has_create_token = 0;
			if (has_capability(HAS_CREATE_TOKEN) &&
			    (ntsec_on(cygwin) ||
			     (has_capability(HAS_NTSEC_BY_DEFAULT) &&
			      !ntsec_off(cygwin))))
				has_create_token = 1;
		}
		if (has_create_token < 1 &&
		    !pwd_authenticated && geteuid() != pw->pw_uid)
			return 0;
	}
	return 1;
}

int check_ntsec(const char *filename)
{
	char *cygwin;
	int allow_ntea = 0;
	int allow_ntsec = 0;
	struct statfs fsstat;

	/* Windows 95/98/ME don't support file system security at all. */
	if (!is_winnt)
		return 0;

	/* Evaluate current CYGWIN settings. */
	cygwin = getenv("CYGWIN");
	allow_ntea = ntea_on(cygwin);
	allow_ntsec = ntsec_on(cygwin) ||
		      (has_capability(HAS_NTSEC_BY_DEFAULT) &&
		       !ntsec_off(cygwin));

	/*
	 * `ntea' is an emulation of POSIX attributes. It doesn't support
	 * real file level security as ntsec on NTFS file systems does
	 * but it supports FAT filesystems. `ntea' is minimum requirement
	 * for security checks.
	 */
	if (allow_ntea)
		return 1;

	/*
	 * Retrieve file system flags. In Cygwin, file system flags are
	 * copied to f_type which has no meaning in Win32 itself.
	 */
	if (statfs(filename, &fsstat))
		return 1;

	/*
	 * Only file systems supporting ACLs are able to set permissions.
	 * `ntsec' is the setting in Cygwin which switches using of NTFS
	 * ACLs to support POSIX permissions on files.
	 */
	if (fsstat.f_type & FS_PERSISTENT_ACLS)
		return allow_ntsec;

	return 0;
}

void register_9x_service(void)
{
        HINSTANCE kerneldll;
        DWORD (*RegisterServiceProcess)(DWORD, DWORD);

	/* The service register mechanism in 9x/Me is pretty different from
	 * NT/2K/XP.  In NT/2K/XP we're using a special service starter
	 * application to register and control sshd as service.  This method
	 * doesn't play nicely with 9x/Me.  For that reason we register here
	 * as service when running under 9x/Me.  This function is only called
	 * by the child sshd when it's going to daemonize.
	 */
	if (is_winnt)
		return;
	if (! (kerneldll = LoadLibrary("KERNEL32.DLL")))
		return;
	if (! (RegisterServiceProcess = (DWORD (*)(DWORD, DWORD))
			  GetProcAddress(kerneldll, "RegisterServiceProcess")))
		return;
	RegisterServiceProcess(0, 1);
}

#endif /* HAVE_CYGWIN */
Commit	Line	Data
3c0ef626	1	/*
3c0ef626	2	* cygwin_util.c
3c0ef626	3	*
700318f3	4	* Copyright (c) 2000, 2001, Corinna Vinschen <vinschen@cygnus.com>
	5	*
	6	* Redistribution and use in source and binary forms, with or without
	7	* modification, are permitted provided that the following conditions
	8	* are met:
	9	* 1. Redistributions of source code must retain the above copyright
	10	* notice, this list of conditions and the following disclaimer.
	11	* 2. Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
3c0ef626	14	*
700318f3	15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	16	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	17	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	18	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	19	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	20	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	21	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	22	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	23	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	24	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
3c0ef626	25	*
	26	* Created: Sat Sep 02 12:17:00 2000 cv
	27	*
	28	* This file contains functions for forcing opened file descriptors to
	29	* binary mode on Windows systems.
	30	*/
	31
	32	#include "includes.h"
	33
	34	RCSID("$Id$");
	35
	36	#ifdef HAVE_CYGWIN
	37
	38	#include <fcntl.h>
	39	#include <stdlib.h>
	40	#include <sys/utsname.h>
	41	#include <sys/vfs.h>
	42	#include <windows.h>
	43	#define is_winnt (GetVersion() < 0x80000000)
	44
	45	#define ntsec_on(c) ((c) && strstr((c),"ntsec") && !strstr((c),"nontsec"))
6a9b3198	46	#define ntsec_off(c) ((c) && strstr((c),"nontsec"))
3c0ef626	47	#define ntea_on(c) ((c) && strstr((c),"ntea") && !strstr((c),"nontea"))
	48
	49	#if defined(open) && open == binary_open
	50	# undef open
	51	#endif
	52	#if defined(pipe) && open == binary_pipe
	53	# undef pipe
	54	#endif
	55
	56	int binary_open(const char *filename, int flags, ...)
	57	{
	58	va_list ap;
	59	mode_t mode;
	60
	61	va_start(ap, flags);
	62	mode = va_arg(ap, mode_t);
	63	va_end(ap);
	64	return open(filename, flags \| O_BINARY, mode);
	65	}
	66
	67	int binary_pipe(int fd[2])
	68	{
	69	int ret = pipe(fd);
	70
	71	if (!ret) {
	72	setmode (fd[0], O_BINARY);
	73	setmode (fd[1], O_BINARY);
	74	}
	75	return ret;
	76	}
	77
6a9b3198	78	#define HAS_CREATE_TOKEN 1
	79	#define HAS_NTSEC_BY_DEFAULT 2
	80
	81	static int has_capability(int what)
	82	{
	83	/* has_capability() basically calls uname() and checks if
	84	specific capabilities of Cygwin can be evaluated from that.
	85	This simplifies the calling functions which only have to ask
	86	for a capability using has_capability() instead of having
	87	to figure that out by themselves. */
	88	static int inited;
	89	static int has_create_token;
	90	static int has_ntsec_by_default;
	91
	92	if (!inited) {
	93	struct utsname uts;
	94	char *c;
	95
	96	if (!uname(&uts)) {
	97	int major_high = 0;
	98	int major_low = 0;
	99	int minor = 0;
	100	int api_major_version = 0;
	101	int api_minor_version = 0;
	102	char *c;
	103
	104	sscanf(uts.release, "%d.%d.%d", &major_high,
	105	&major_low, &minor);
	106	c = strchr(uts.release, '(');
	107	if (c)
	108	sscanf(c + 1, "%d.%d", &api_major_version,
	109	&api_minor_version);
	110	if (major_high > 1 \|\|
	111	(major_high == 1 && (major_low > 3 \|\|
	112	(major_low == 3 && minor >= 2))))
	113	has_create_token = 1;
	114	if (api_major_version > 0 \|\| api_minor_version >= 56)
	115	has_ntsec_by_default = 1;
	116	inited = 1;
	117	}
	118	}
	119	switch (what) {
	120	case HAS_CREATE_TOKEN:
	121	return has_create_token;
	122	case HAS_NTSEC_BY_DEFAULT:
	123	return has_ntsec_by_default;
	124	}
	125	return 0;
	126	}
	127
e9a17296	128	int check_nt_auth(int pwd_authenticated, struct passwd *pw)
3c0ef626	129	{
	130	/*
	131	* The only authentication which is able to change the user
	132	* context on NT systems is the password authentication. So
	133	* we deny all requsts for changing the user context if another
	134	* authentication method is used.
	135	*
	136	* This doesn't apply to Cygwin versions >= 1.3.2 anymore which
	137	* uses the undocumented NtCreateToken() call to create a user
	138	* token if the process has the appropriate privileges and if
	139	* CYGWIN ntsec setting is on.
	140	*/
	141	static int has_create_token = -1;
	142
e9a17296	143	if (pw == NULL)
e9a17296	144	return 0;
3c0ef626	145	if (is_winnt) {
3c0ef626	146	if (has_create_token < 0) {
3c0ef626	147	char *cygwin = getenv("CYGWIN");
	148
	149	has_create_token = 0;
6a9b3198	150	if (has_capability(HAS_CREATE_TOKEN) &&
	151	(ntsec_on(cygwin) \|\|
	152	(has_capability(HAS_NTSEC_BY_DEFAULT) &&
	153	!ntsec_off(cygwin))))
	154	has_create_token = 1;
3c0ef626	155	}
3c0ef626	156	if (has_create_token < 1 &&
e9a17296	157	!pwd_authenticated && geteuid() != pw->pw_uid)
3c0ef626	158	return 0;
	159	}
	160	return 1;
	161	}
	162
	163	int check_ntsec(const char *filename)
	164	{
	165	char *cygwin;
	166	int allow_ntea = 0;
	167	int allow_ntsec = 0;
	168	struct statfs fsstat;
	169
	170	/* Windows 95/98/ME don't support file system security at all. */
	171	if (!is_winnt)
	172	return 0;
	173
	174	/* Evaluate current CYGWIN settings. */
	175	cygwin = getenv("CYGWIN");
	176	allow_ntea = ntea_on(cygwin);
6a9b3198	177	allow_ntsec = ntsec_on(cygwin) \|\|
	178	(has_capability(HAS_NTSEC_BY_DEFAULT) &&
	179	!ntsec_off(cygwin));
3c0ef626	180
	181	/*
	182	* `ntea' is an emulation of POSIX attributes. It doesn't support
	183	* real file level security as ntsec on NTFS file systems does
	184	* but it supports FAT filesystems. `ntea' is minimum requirement
	185	* for security checks.
	186	*/
	187	if (allow_ntea)
	188	return 1;
	189
	190	/*
	191	* Retrieve file system flags. In Cygwin, file system flags are
	192	* copied to f_type which has no meaning in Win32 itself.
	193	*/
	194	if (statfs(filename, &fsstat))
	195	return 1;
	196
	197	/*
	198	* Only file systems supporting ACLs are able to set permissions.
	199	* `ntsec' is the setting in Cygwin which switches using of NTFS
	200	* ACLs to support POSIX permissions on files.
	201	*/
	202	if (fsstat.f_type & FS_PERSISTENT_ACLS)
	203	return allow_ntsec;
	204
	205	return 0;
	206	}
	207
e9a17296	208	void register_9x_service(void)
	209	{
	210	HINSTANCE kerneldll;
	211	DWORD (*RegisterServiceProcess)(DWORD, DWORD);
	212
	213	/* The service register mechanism in 9x/Me is pretty different from
	214	* NT/2K/XP. In NT/2K/XP we're using a special service starter
	215	* application to register and control sshd as service. This method
	216	* doesn't play nicely with 9x/Me. For that reason we register here
	217	* as service when running under 9x/Me. This function is only called
	218	* by the child sshd when it's going to daemonize.
	219	*/
	220	if (is_winnt)
	221	return;
	222	if (! (kerneldll = LoadLibrary("KERNEL32.DLL")))
	223	return;
	224	if (! (RegisterServiceProcess = (DWORD (*)(DWORD, DWORD))
	225	GetProcAddress(kerneldll, "RegisterServiceProcess")))
	226	return;
	227	RegisterServiceProcess(0, 1);
	228	}
	229
3c0ef626	230	#endif /* HAVE_CYGWIN */