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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "primpl.h"
/*
* ntsec.c
*
* Implement the POSIX-style mode bits (access permissions) for
* files and other securable objects in Windows NT using Windows
* NT's security descriptors with appropriate discretionary
* access-control lists.
*/
/*
* The security identifiers (SIDs) for owner, primary group,
* and the Everyone (World) group.
*
* These SIDs are looked up during NSPR initialization and
* saved in this global structure (see _PR_NT_InitSids) so
* that _PR_NT_MakeSecurityDescriptorACL doesn't need to
* look them up every time.
*/
static struct {
PSID owner;
PSID group;
PSID everyone;
} _pr_nt_sids;
/*
* Initialize the SIDs for owner, primary group, and the Everyone
* group in the _pr_nt_sids structure.
*
* This function needs to be called by NSPR initialization.
*/
void _PR_NT_InitSids(void) {
#ifdef WINCE /* not supported */
return;
#else
SID_IDENTIFIER_AUTHORITY SIDAuthWorld = SECURITY_WORLD_SID_AUTHORITY;
HANDLE hToken = NULL; /* initialized to an arbitrary value to
* silence a Purify UMR warning */
PSID infoBuffer[1024 / sizeof(PSID)]; /* defined as an array of PSIDs
* to force proper alignment */
PTOKEN_OWNER pTokenOwner = (PTOKEN_OWNER)infoBuffer;
PTOKEN_PRIMARY_GROUP pTokenPrimaryGroup = (PTOKEN_PRIMARY_GROUP)infoBuffer;
DWORD dwLength;
BOOL rv;
/*
* Look up and make a copy of the owner and primary group
* SIDs in the access token of the calling process.
*/
rv = OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken);
if (rv == 0) {
/*
* On non-NT systems, this function is not implemented
* (error code ERROR_CALL_NOT_IMPLEMENTED), and neither are
* the other security functions. There is no point in
* going further.
*
* A process with insufficient access permissions may fail
* with the error code ERROR_ACCESS_DENIED.
*/
PR_LOG(_pr_io_lm, PR_LOG_DEBUG,
("_PR_NT_InitSids: OpenProcessToken() failed. Error: %d",
GetLastError()));
return;
}
rv = GetTokenInformation(hToken, TokenOwner, infoBuffer, sizeof(infoBuffer),
&dwLength);
PR_ASSERT(rv != 0);
dwLength = GetLengthSid(pTokenOwner->Owner);
_pr_nt_sids.owner = (PSID)PR_Malloc(dwLength);
PR_ASSERT(_pr_nt_sids.owner != NULL);
rv = CopySid(dwLength, _pr_nt_sids.owner, pTokenOwner->Owner);
PR_ASSERT(rv != 0);
rv = GetTokenInformation(hToken, TokenPrimaryGroup, infoBuffer,
sizeof(infoBuffer), &dwLength);
PR_ASSERT(rv != 0);
dwLength = GetLengthSid(pTokenPrimaryGroup->PrimaryGroup);
_pr_nt_sids.group = (PSID)PR_Malloc(dwLength);
PR_ASSERT(_pr_nt_sids.group != NULL);
rv = CopySid(dwLength, _pr_nt_sids.group, pTokenPrimaryGroup->PrimaryGroup);
PR_ASSERT(rv != 0);
rv = CloseHandle(hToken);
PR_ASSERT(rv != 0);
/* Create a well-known SID for the Everyone group. */
rv = AllocateAndInitializeSid(&SIDAuthWorld, 1, SECURITY_WORLD_RID, 0, 0, 0,
0, 0, 0, 0, &_pr_nt_sids.everyone);
PR_ASSERT(rv != 0);
#endif
}
/*
* Free the SIDs for owner, primary group, and the Everyone group
* in the _pr_nt_sids structure.
*
* This function needs to be called by NSPR cleanup.
*/
void _PR_NT_FreeSids(void) {
#ifdef WINCE
return;
#else
if (_pr_nt_sids.owner) {
PR_Free(_pr_nt_sids.owner);
}
if (_pr_nt_sids.group) {
PR_Free(_pr_nt_sids.group);
}
if (_pr_nt_sids.everyone) {
FreeSid(_pr_nt_sids.everyone);
}
#endif
}
/*
* Construct a security descriptor whose discretionary access-control
* list implements the specified mode bits. The SIDs for owner, group,
* and everyone are obtained from the global _pr_nt_sids structure.
* Both the security descriptor and access-control list are returned
* and should be freed by a _PR_NT_FreeSecurityDescriptorACL call.
*
* The accessTable array maps NSPR's read, write, and execute access
* rights to the corresponding NT access rights for the securable
* object.
*/
PRStatus _PR_NT_MakeSecurityDescriptorACL(PRIntn mode, DWORD accessTable[],
PSECURITY_DESCRIPTOR* resultSD,
PACL* resultACL) {
#ifdef WINCE
PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0);
return PR_FAILURE;
#else
PSECURITY_DESCRIPTOR pSD = NULL;
PACL pACL = NULL;
DWORD cbACL; /* size of ACL */
DWORD accessMask;
if (_pr_nt_sids.owner == NULL) {
PR_SetError(PR_NOT_IMPLEMENTED_ERROR, 0);
return PR_FAILURE;
}
pSD = (PSECURITY_DESCRIPTOR)PR_Malloc(SECURITY_DESCRIPTOR_MIN_LENGTH);
if (pSD == NULL) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
if (!InitializeSecurityDescriptor(pSD, SECURITY_DESCRIPTOR_REVISION)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
if (!SetSecurityDescriptorOwner(pSD, _pr_nt_sids.owner, FALSE)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
if (!SetSecurityDescriptorGroup(pSD, _pr_nt_sids.group, FALSE)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
/*
* Construct a discretionary access-control list with three
* access-control entries, one each for owner, primary group,
* and Everyone.
*/
cbACL = sizeof(ACL) + 3 * (sizeof(ACCESS_ALLOWED_ACE) - sizeof(DWORD)) +
GetLengthSid(_pr_nt_sids.owner) + GetLengthSid(_pr_nt_sids.group) +
GetLengthSid(_pr_nt_sids.everyone);
pACL = (PACL)PR_Malloc(cbACL);
if (pACL == NULL) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
if (!InitializeAcl(pACL, cbACL, ACL_REVISION)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
accessMask = 0;
if (mode & 00400) {
accessMask |= accessTable[0];
}
if (mode & 00200) {
accessMask |= accessTable[1];
}
if (mode & 00100) {
accessMask |= accessTable[2];
}
if (accessMask &&
!AddAccessAllowedAce(pACL, ACL_REVISION, accessMask, _pr_nt_sids.owner)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
accessMask = 0;
if (mode & 00040) {
accessMask |= accessTable[0];
}
if (mode & 00020) {
accessMask |= accessTable[1];
}
if (mode & 00010) {
accessMask |= accessTable[2];
}
if (accessMask &&
!AddAccessAllowedAce(pACL, ACL_REVISION, accessMask, _pr_nt_sids.group)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
accessMask = 0;
if (mode & 00004) {
accessMask |= accessTable[0];
}
if (mode & 00002) {
accessMask |= accessTable[1];
}
if (mode & 00001) {
accessMask |= accessTable[2];
}
if (accessMask && !AddAccessAllowedAce(pACL, ACL_REVISION, accessMask,
_pr_nt_sids.everyone)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
if (!SetSecurityDescriptorDacl(pSD, TRUE, pACL, FALSE)) {
_PR_MD_MAP_DEFAULT_ERROR(GetLastError());
goto failed;
}
*resultSD = pSD;
*resultACL = pACL;
return PR_SUCCESS;
failed:
if (pSD) {
PR_Free(pSD);
}
if (pACL) {
PR_Free(pACL);
}
return PR_FAILURE;
#endif
}
/*
* Free the specified security descriptor and access-control list
* previously created by _PR_NT_MakeSecurityDescriptorACL.
*/
void _PR_NT_FreeSecurityDescriptorACL(PSECURITY_DESCRIPTOR pSD, PACL pACL) {
if (pSD) {
PR_Free(pSD);
}
if (pACL) {
PR_Free(pACL);
}
}