newlib/winsup/cygwin/sec_helper.cc
Corinna Vinschen e6fbf13e48 * cygheap.cc (cygheap_init): Fix formatting. Remove comment. Set
shared_prefix depending only on terminal service capability.
	* dcrt0.cc (dll_crt0_1): Don't call set_cygwin_privileges here.
	* fhandler_fifo.cc (fhandler_fifo::open): Create the mutex as global
	object.
	* posix_ipc.cc (ipc_mutex_init): Use cygheap->shared_prefix.
	(ipc_cond_init): Ditto.
	* sec_helper.cc (privilege_name): Make static.  Use LookupPrivilegeName
	directly to be independent of the state of cygheap.
	(set_privilege): Take a LUID as parameter instead of an index value.
	Only print debug output in case of failure.
	(set_cygwin_privileges): Add comment.  Use LookupPrivilegeValue to
	get privilege LUIDs.
	(init_global_security): Call set_cygwin_privileges here.
	* security.h (privilege_name): Drop declaration.
	(set_privilege): Declare according to above change.
	(set_process_privilege): Call privilege_luid to get LUID.
	(_push_thread_privilege): Ditto.
	* shared.cc (open_shared): Add comment.  On systems supporting the
	SeCreateGlobalPrivilege, try to create/open global shared memory first.
	Fall back to local shared memory if that fails.
	* thread.cc (semaphore::semaphore): Use cygheap->shared_prefix.
	* wincap.h (wincapc::has_create_global_privilege): New element.
	* wincap.cc: Implement above element throughout.
2007-03-29 16:37:36 +00:00

618 lines
16 KiB
C++

/* sec_helper.cc: NT security helper functions
Copyright 2000, 2001, 2002, 2003, 2004, 2006, 2007 Red Hat, Inc.
Written by Corinna Vinschen <corinna@vinschen.de>
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 <grp.h>
#include <pwd.h>
#include <unistd.h>
#include <stdlib.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/acl.h>
#include <ctype.h>
#include <wingdi.h>
#include <winuser.h>
#include <wininet.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "pinfo.h"
#include "cygheap.h"
#include "cygtls.h"
#include "pwdgrp.h"
/* General purpose security attribute objects for global use. */
SECURITY_ATTRIBUTES NO_COPY sec_none;
SECURITY_ATTRIBUTES NO_COPY sec_none_nih;
SECURITY_ATTRIBUTES NO_COPY sec_all;
SECURITY_ATTRIBUTES NO_COPY sec_all_nih;
MKSID (well_known_null_sid, "S-1-0-0",
SECURITY_NULL_SID_AUTHORITY, 1, SECURITY_NULL_RID);
MKSID (well_known_world_sid, "S-1-1-0",
SECURITY_WORLD_SID_AUTHORITY, 1, SECURITY_WORLD_RID);
MKSID (well_known_local_sid, "S-1-2-0",
SECURITY_LOCAL_SID_AUTHORITY, 1, SECURITY_LOCAL_RID);
MKSID (well_known_creator_owner_sid, "S-1-3-0",
SECURITY_CREATOR_SID_AUTHORITY, 1, SECURITY_CREATOR_OWNER_RID);
MKSID (well_known_creator_group_sid, "S-1-3-1",
SECURITY_CREATOR_SID_AUTHORITY, 1, SECURITY_CREATOR_GROUP_RID);
MKSID (well_known_dialup_sid, "S-1-5-1",
SECURITY_NT_AUTHORITY, 1, SECURITY_DIALUP_RID);
MKSID (well_known_network_sid, "S-1-5-2",
SECURITY_NT_AUTHORITY, 1, SECURITY_NETWORK_RID);
MKSID (well_known_batch_sid, "S-1-5-3",
SECURITY_NT_AUTHORITY, 1, SECURITY_BATCH_RID);
MKSID (well_known_interactive_sid, "S-1-5-4",
SECURITY_NT_AUTHORITY, 1, SECURITY_INTERACTIVE_RID);
MKSID (well_known_service_sid, "S-1-5-6",
SECURITY_NT_AUTHORITY, 1, SECURITY_SERVICE_RID);
MKSID (well_known_authenticated_users_sid, "S-1-5-11",
SECURITY_NT_AUTHORITY, 1, SECURITY_AUTHENTICATED_USER_RID);
MKSID (well_known_this_org_sid, "S-1-5-15",
SECURITY_NT_AUTHORITY, 1, 15);
MKSID (well_known_system_sid, "S-1-5-18",
SECURITY_NT_AUTHORITY, 1, SECURITY_LOCAL_SYSTEM_RID);
MKSID (well_known_admins_sid, "S-1-5-32-544",
SECURITY_NT_AUTHORITY, 2, SECURITY_BUILTIN_DOMAIN_RID,
DOMAIN_ALIAS_RID_ADMINS);
MKSID (fake_logon_sid, "S-1-5-5-0-0",
SECURITY_NT_AUTHORITY, 3, SECURITY_LOGON_IDS_RID, 0, 0);
bool
cygpsid::operator== (const char *nsidstr) const
{
cygsid nsid (nsidstr);
return psid == nsid;
}
__uid32_t
cygpsid::get_id (BOOL search_grp, int *type)
{
/* First try to get SID from group, then passwd */
__uid32_t id = ILLEGAL_UID;
if (search_grp)
{
struct __group32 *gr;
if (cygheap->user.groups.pgsid == psid)
id = myself->gid;
else if ((gr = internal_getgrsid (*this)))
id = gr->gr_gid;
if (id != ILLEGAL_UID)
{
if (type)
*type = GROUP;
return id;
}
}
if (!search_grp || type)
{
struct passwd *pw;
if (*this == cygheap->user.sid ())
id = myself->uid;
else if ((pw = internal_getpwsid (*this)))
id = pw->pw_uid;
if (id != ILLEGAL_UID && type)
*type = USER;
}
return id;
}
char *
cygpsid::string (char *nsidstr) const
{
char *t;
DWORD i;
if (!psid || !nsidstr)
return NULL;
strcpy (nsidstr, "S-1-");
t = nsidstr + sizeof ("S-1-") - 1;
t += __small_sprintf (t, "%u", GetSidIdentifierAuthority (psid)->Value[5]);
for (i = 0; i < *GetSidSubAuthorityCount (psid); ++i)
t += __small_sprintf (t, "-%lu", *GetSidSubAuthority (psid, i));
return nsidstr;
}
PSID
cygsid::get_sid (DWORD s, DWORD cnt, DWORD *r, bool well_known)
{
DWORD i;
SID_IDENTIFIER_AUTHORITY sid_auth = {0,0,0,0,0,0};
if (s > 255 || cnt < 1 || cnt > 8)
{
psid = NO_SID;
return NULL;
}
sid_auth.Value[5] = s;
set ();
InitializeSid (psid, &sid_auth, cnt);
for (i = 0; i < cnt; ++i)
memcpy ((char *) psid + 8 + sizeof (DWORD) * i, &r[i], sizeof (DWORD));
well_known_sid = well_known;
return psid;
}
const PSID
cygsid::getfromstr (const char *nsidstr, bool well_known)
{
char *lasts;
DWORD s, cnt = 0;
DWORD r[8];
if (nsidstr && !strncmp (nsidstr, "S-1-", 4))
{
s = strtoul (nsidstr + 4, &lasts, 10);
while (cnt < 8 && *lasts == '-')
r[cnt++] = strtoul (lasts + 1, &lasts, 10);
if (!*lasts)
return get_sid (s, cnt, r, well_known);
}
return psid = NO_SID;
}
BOOL
cygsid::getfrompw (const struct passwd *pw)
{
char *sp = (pw && pw->pw_gecos) ? strrchr (pw->pw_gecos, ',') : NULL;
return (*this = sp ? sp + 1 : sp) != NULL;
}
BOOL
cygsid::getfromgr (const struct __group32 *gr)
{
char *sp = (gr && gr->gr_passwd) ? gr->gr_passwd : NULL;
return (*this = sp) != NULL;
}
cygsid *
cygsidlist::alloc_sids (int n)
{
if (n > 0)
return (cygsid *) cmalloc (HEAP_STR, n * sizeof (cygsid));
else
return NULL;
}
void
cygsidlist::free_sids ()
{
if (sids)
cfree (sids);
sids = NULL;
cnt = maxcnt = 0;
type = cygsidlist_empty;
}
BOOL
cygsidlist::add (const PSID nsi, bool well_known)
{
if (contains (nsi))
return TRUE;
if (cnt >= maxcnt)
{
cygsid *tmp = new cygsid [2 * maxcnt];
if (!tmp)
return FALSE;
maxcnt *= 2;
for (int i = 0; i < cnt; ++i)
tmp[i] = sids[i];
delete [] sids;
sids = tmp;
}
if (well_known)
sids[cnt++] *= nsi;
else
sids[cnt++] = nsi;
return TRUE;
}
bool
get_sids_info (cygpsid owner_sid, cygpsid group_sid, __uid32_t * uidret, __gid32_t * gidret)
{
struct passwd *pw;
struct __group32 *gr = NULL;
bool ret = false;
owner_sid.debug_print ("get_sids_info: owner SID =");
group_sid.debug_print ("get_sids_info: group SID =");
if (group_sid == cygheap->user.groups.pgsid)
*gidret = myself->gid;
else if ((gr = internal_getgrsid (group_sid)))
*gidret = gr->gr_gid;
else
*gidret = ILLEGAL_GID;
if (owner_sid == cygheap->user.sid ())
{
*uidret = myself->uid;
if (*gidret == myself->gid)
ret = true;
else
ret = (internal_getgroups (0, NULL, &group_sid) > 0);
}
else if ((pw = internal_getpwsid (owner_sid)))
{
*uidret = pw->pw_uid;
if (gr || (*gidret != ILLEGAL_GID
&& (gr = internal_getgrgid (*gidret))))
for (int idx = 0; gr->gr_mem[idx]; ++idx)
if ((ret = strcasematch (pw->pw_name, gr->gr_mem[idx])))
break;
}
else
*uidret = ILLEGAL_UID;
return ret;
}
PSECURITY_DESCRIPTOR
security_descriptor::malloc (size_t nsize)
{
free ();
if ((psd = (PSECURITY_DESCRIPTOR) ::malloc (nsize)))
sd_size = nsize;
return psd;
}
PSECURITY_DESCRIPTOR
security_descriptor::realloc (size_t nsize)
{
PSECURITY_DESCRIPTOR tmp;
if (!(tmp = (PSECURITY_DESCRIPTOR) ::realloc (psd, nsize)))
return NULL;
sd_size = nsize;
return psd = tmp;
}
void
security_descriptor::free ()
{
if (psd)
::free (psd);
psd = NULL;
sd_size = 0;
}
#if 0 // unused
#define SIDLEN (sidlen = MAX_SID_LEN, &sidlen)
#define DOMLEN (domlen = INTERNET_MAX_HOST_NAME_LENGTH, &domlen)
BOOL
lookup_name (const char *name, const char *logsrv, PSID ret_sid)
{
cygsid sid;
DWORD sidlen;
char domuser[INTERNET_MAX_HOST_NAME_LENGTH + UNLEN + 2];
char dom[INTERNET_MAX_HOST_NAME_LENGTH + 1];
DWORD domlen;
SID_NAME_USE acc_type;
debug_printf ("name : %s", name ? name : "NULL");
if (!name)
return FALSE;
if (cygheap->user.domain ())
{
strcat (strcat (strcpy (domuser, cygheap->user.domain ()), "\\"), name);
if (LookupAccountName (NULL, domuser, sid, SIDLEN, dom, DOMLEN, &acc_type)
&& legal_sid_type (acc_type))
goto got_it;
if (logsrv && *logsrv
&& LookupAccountName (logsrv, domuser, sid, SIDLEN,
dom, DOMLEN, &acc_type)
&& legal_sid_type (acc_type))
goto got_it;
}
if (logsrv && *logsrv)
{
if (LookupAccountName (logsrv, name, sid, SIDLEN, dom, DOMLEN, &acc_type)
&& legal_sid_type (acc_type))
goto got_it;
if (acc_type == SidTypeDomain)
{
strcat (strcat (strcpy (domuser, dom), "\\"), name);
if (LookupAccountName (logsrv, domuser, sid, SIDLEN,
dom, DOMLEN, &acc_type))
goto got_it;
}
}
if (LookupAccountName (NULL, name, sid, SIDLEN, dom, DOMLEN, &acc_type)
&& legal_sid_type (acc_type))
goto got_it;
if (acc_type == SidTypeDomain)
{
strcat (strcat (strcpy (domuser, dom), "\\"), name);
if (LookupAccountName (NULL, domuser, sid, SIDLEN, dom, DOMLEN,&acc_type))
goto got_it;
}
debug_printf ("LookupAccountName (%s) %E", name);
__seterrno ();
return FALSE;
got_it:
debug_printf ("sid : [%d]", *GetSidSubAuthority ((PSID) sid,
*GetSidSubAuthorityCount ((PSID) sid) - 1));
if (ret_sid)
memcpy (ret_sid, sid, sidlen);
return TRUE;
}
#undef SIDLEN
#undef DOMLEN
#endif //unused
/* Order must be same as cygpriv_idx in security.h. */
static const char *cygpriv[] =
{
SE_CREATE_TOKEN_NAME,
SE_ASSIGNPRIMARYTOKEN_NAME,
SE_LOCK_MEMORY_NAME,
SE_INCREASE_QUOTA_NAME,
SE_UNSOLICITED_INPUT_NAME,
SE_MACHINE_ACCOUNT_NAME,
SE_TCB_NAME,
SE_SECURITY_NAME,
SE_TAKE_OWNERSHIP_NAME,
SE_LOAD_DRIVER_NAME,
SE_SYSTEM_PROFILE_NAME,
SE_SYSTEMTIME_NAME,
SE_PROF_SINGLE_PROCESS_NAME,
SE_INC_BASE_PRIORITY_NAME,
SE_CREATE_PAGEFILE_NAME,
SE_CREATE_PERMANENT_NAME,
SE_BACKUP_NAME,
SE_RESTORE_NAME,
SE_SHUTDOWN_NAME,
SE_DEBUG_NAME,
SE_AUDIT_NAME,
SE_SYSTEM_ENVIRONMENT_NAME,
SE_CHANGE_NOTIFY_NAME,
SE_REMOTE_SHUTDOWN_NAME,
SE_CREATE_GLOBAL_NAME,
SE_UNDOCK_NAME,
SE_MANAGE_VOLUME_NAME,
SE_IMPERSONATE_NAME,
SE_ENABLE_DELEGATION_NAME,
SE_SYNC_AGENT_NAME,
SE_RELABEL_NAME,
SE_INCREASE_WORKING_SET_NAME,
SE_TIME_ZONE_NAME,
SE_CREATE_SYMBOLIC_LINK_NAME
};
const LUID *
privilege_luid (cygpriv_idx idx)
{
if (idx < 0 || idx >= SE_NUM_PRIVS)
return NULL;
if (!cygheap->luid[idx].LowPart && !cygheap->luid[idx].HighPart
&& !LookupPrivilegeValue (NULL, cygpriv[idx], &cygheap->luid[idx]))
{
__seterrno ();
return NULL;
}
return &cygheap->luid[idx];
}
const LUID *
privilege_luid_by_name (const char *pname)
{
int idx;
if (!pname)
return NULL;
for (idx = 0; idx < SE_NUM_PRIVS; ++idx)
if (!strcmp (pname, cygpriv[idx]))
return privilege_luid ((cygpriv_idx) idx);
return NULL;
}
static const char *
privilege_name (const LUID *priv_luid, char *buf, DWORD *size)
{
if (!priv_luid || !LookupPrivilegeName (NULL, (LUID *) priv_luid, buf, size))
return "<unknown privilege>";
return buf;
}
int
set_privilege (HANDLE token, const LUID *priv_luid, bool enable)
{
int ret = -1;
TOKEN_PRIVILEGES new_priv, orig_priv;
DWORD size;
if (!priv_luid)
{
__seterrno ();
goto out;
}
new_priv.PrivilegeCount = 1;
new_priv.Privileges[0].Luid = *priv_luid;
new_priv.Privileges[0].Attributes = enable ? SE_PRIVILEGE_ENABLED : 0;
if (!AdjustTokenPrivileges (token, FALSE, &new_priv,
sizeof orig_priv, &orig_priv, &size))
{
__seterrno ();
goto out;
}
/* AdjustTokenPrivileges returns TRUE even if the privilege could not
be enabled. GetLastError () returns an correct error code, though. */
if (enable && GetLastError () == ERROR_NOT_ALL_ASSIGNED)
{
__seterrno ();
goto out;
}
/* If orig_priv.PrivilegeCount is 0, the privilege hasn't been changed. */
if (!orig_priv.PrivilegeCount)
ret = enable ? 1 : 0;
else
ret = (orig_priv.Privileges[0].Attributes & SE_PRIVILEGE_ENABLED) ? 1 : 0;
out:
if (ret < 0)
{
DWORD siz = 256;
char buf[siz];
debug_printf ("%d = set_privilege ((token %x) %s, %d)",
ret, token, privilege_name (priv_luid, buf, &siz), enable);
}
return ret;
}
/* This is called very early in process initialization. The code must
not depend on anything. */
void
set_cygwin_privileges (HANDLE token)
{
LUID priv_luid;
if (LookupPrivilegeValue (NULL, SE_RESTORE_NAME, &priv_luid))
set_privilege (token, &priv_luid, true);
if (LookupPrivilegeValue (NULL, SE_BACKUP_NAME, &priv_luid))
set_privilege (token, &priv_luid, true);
if (LookupPrivilegeValue (NULL, SE_CREATE_GLOBAL_NAME, &priv_luid))
set_privilege (token, &priv_luid, true);
}
/* Function to return a common SECURITY_DESCRIPTOR that
allows all access. */
SECURITY_DESCRIPTOR *__stdcall
get_null_sd ()
{
static NO_COPY SECURITY_DESCRIPTOR sd;
static NO_COPY SECURITY_DESCRIPTOR *null_sdp;
if (!null_sdp)
{
InitializeSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION);
SetSecurityDescriptorDacl (&sd, TRUE, 0, FALSE);
null_sdp = &sd;
}
return null_sdp;
}
/* Initialize global security attributes.
Called from dcrt0.cc (_dll_crt0). */
void
init_global_security ()
{
sec_none.nLength = sec_none_nih.nLength =
sec_all.nLength = sec_all_nih.nLength = sizeof (SECURITY_ATTRIBUTES);
sec_none.bInheritHandle = sec_all.bInheritHandle = TRUE;
sec_none_nih.bInheritHandle = sec_all_nih.bInheritHandle = FALSE;
sec_none.lpSecurityDescriptor = sec_none_nih.lpSecurityDescriptor = NULL;
sec_all.lpSecurityDescriptor = sec_all_nih.lpSecurityDescriptor =
get_null_sd ();
set_cygwin_privileges (hProcToken);
}
bool
sec_acl (PACL acl, bool original, bool admins, PSID sid1, PSID sid2, DWORD access2)
{
size_t acl_len = MAX_DACL_LEN(5);
LPVOID pAce;
cygpsid psid;
#ifdef DEBUGGING
if ((unsigned long) acl % 4)
api_fatal ("Incorrectly aligned incoming ACL buffer!");
#endif
if (!InitializeAcl (acl, acl_len, ACL_REVISION))
{
debug_printf ("InitializeAcl %E");
return false;
}
if (sid1)
if (!AddAccessAllowedAce (acl, ACL_REVISION,
GENERIC_ALL, sid1))
debug_printf ("AddAccessAllowedAce(sid1) %E");
if (original && (psid = cygheap->user.saved_sid ())
&& psid != sid1 && psid != well_known_system_sid)
if (!AddAccessAllowedAce (acl, ACL_REVISION,
GENERIC_ALL, psid))
debug_printf ("AddAccessAllowedAce(original) %E");
if (sid2)
if (!AddAccessAllowedAce (acl, ACL_REVISION,
access2, sid2))
debug_printf ("AddAccessAllowedAce(sid2) %E");
if (admins)
if (!AddAccessAllowedAce (acl, ACL_REVISION,
GENERIC_ALL, well_known_admins_sid))
debug_printf ("AddAccessAllowedAce(admin) %E");
if (!AddAccessAllowedAce (acl, ACL_REVISION,
GENERIC_ALL, well_known_system_sid))
debug_printf ("AddAccessAllowedAce(system) %E");
FindFirstFreeAce (acl, &pAce);
if (pAce)
acl->AclSize = (char *) pAce - (char *) acl;
else
debug_printf ("FindFirstFreeAce %E");
return true;
}
PSECURITY_ATTRIBUTES __stdcall
__sec_user (PVOID sa_buf, PSID sid1, PSID sid2, DWORD access2, BOOL inherit)
{
PSECURITY_ATTRIBUTES psa = (PSECURITY_ATTRIBUTES) sa_buf;
PSECURITY_DESCRIPTOR psd = (PSECURITY_DESCRIPTOR)
((char *) sa_buf + sizeof (*psa));
PACL acl = (PACL) ((char *) sa_buf + sizeof (*psa) + sizeof (*psd));
#ifdef DEBUGGING
if ((unsigned long) sa_buf % 4)
api_fatal ("Incorrectly aligned incoming SA buffer!");
#endif
if (!sec_acl (acl, true, true, sid1, sid2, access2))
return inherit ? &sec_none : &sec_none_nih;
if (!InitializeSecurityDescriptor (psd, SECURITY_DESCRIPTOR_REVISION))
debug_printf ("InitializeSecurityDescriptor %E");
/*
* Setting the owner lets the created security attribute not work
* on NT4 SP3 Server. Don't know why, but the function still does
* what it should do also if the owner isn't set.
*/
#if 0
if (!SetSecurityDescriptorOwner (psd, sid, FALSE))
debug_printf ("SetSecurityDescriptorOwner %E");
#endif
if (!SetSecurityDescriptorDacl (psd, TRUE, acl, FALSE))
debug_printf ("SetSecurityDescriptorDacl %E");
psa->nLength = sizeof (SECURITY_ATTRIBUTES);
psa->lpSecurityDescriptor = psd;
psa->bInheritHandle = inherit;
return psa;
}