windows-nt/Source/XPSP1/NT/admin/services/sched/common/security.cxx
2020-09-26 16:20:57 +08:00

357 lines
9.7 KiB
C++

//+---------------------------------------------------------------------------
//
// Microsoft Windows
// Copyright (C) Microsoft Corporation, 1992 - 1996.
//
// File: security.cxx
//
// Contents:
//
// Classes: None.
//
// Functions: None.
//
// History: 26-Jun-96 MarkBl Created
//
//----------------------------------------------------------------------------
#include "..\pch\headers.hxx"
#pragma hdrstop
#include <common.hxx> // MAX_SID_SIZE
#include "..\inc\debug.hxx"
#include "..\inc\security.hxx"
//+---------------------------------------------------------------------------
//
// Function: CreateSecurityDescriptor
//
// Synopsis: Create a security descriptor with the ACE information
// specified.
//
// Arguments: [AceCount] -- ACE count (no. of rgMyAce and rgAce elements).
// [rgMyAce] -- ACE specification array.
// [rgAce] -- Caller allocated array of ptrs to ACEs so
// this function doesn't have to allocate it.
//
// Returns: TRUE -- Function succeeded,
// FALSE -- Otherwise.
//
// Notes: None.
//
//----------------------------------------------------------------------------
PSECURITY_DESCRIPTOR
CreateSecurityDescriptor(
DWORD AceCount,
MYACE rgMyAce[],
PACCESS_ALLOWED_ACE rgAce[],
DWORD * pStatus)
{
PSECURITY_DESCRIPTOR pSecurityDescriptor = NULL;
PACL pAcl = NULL;
DWORD LengthAces = 0;
DWORD LengthAcl;
DWORD i;
DWORD Status;
for (i = 0; i < AceCount; i++)
{
rgAce[i] = CreateAccessAllowedAce(rgMyAce[i].pSid,
rgMyAce[i].AccessMask,
0,
rgMyAce[i].InheritFlags,
&Status);
if (rgAce[i] == NULL)
{
goto ErrorExit;
}
LengthAces += rgAce[i]->Header.AceSize;
}
//
// Calculate ACL and SD sizes
//
LengthAcl = sizeof(ACL) + LengthAces;
//
// Create the ACL.
//
pAcl = (PACL)LocalAlloc(LMEM_FIXED, LengthAcl);
if (pAcl == NULL)
{
Status = ERROR_NOT_ENOUGH_MEMORY;
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, ACL allocation failed\n"));
goto ErrorExit;
}
if (!InitializeAcl(pAcl, LengthAcl, ACL_REVISION))
{
Status = GetLastError();
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, InitializeAcl failed, " \
"status = 0x%lx\n",
Status));
goto ErrorExit;
}
for (i = 0; i < AceCount; i++)
{
if (!AddAce(pAcl,
ACL_REVISION,
0,
rgAce[i],
rgAce[i]->Header.AceSize))
{
Status = GetLastError();
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, AddAce[%l] failed, " \
"status = 0x%lx\n", i, Status));
goto ErrorExit;
}
LocalFree(rgAce[i]);
rgAce[i] = NULL;
}
//
// Create the security descriptor.
//
pSecurityDescriptor = LocalAlloc(LMEM_FIXED,
SECURITY_DESCRIPTOR_MIN_LENGTH);
if (pSecurityDescriptor == NULL)
{
Status = ERROR_NOT_ENOUGH_MEMORY;
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, SECURITY_DESCRIPTOR allocation " \
"failed\n"));
goto ErrorExit;
}
if (!InitializeSecurityDescriptor(pSecurityDescriptor,
SECURITY_DESCRIPTOR_REVISION))
{
Status = GetLastError();
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, InitializeSecurityDescriptor " \
"failed, status = 0x%lx\n",
Status));
goto ErrorExit;
}
if (!SetSecurityDescriptorDacl(pSecurityDescriptor,
TRUE,
pAcl,
FALSE))
{
Status = GetLastError();
schDebugOut((DEB_ERROR,
"CreateSecurityDescriptor, SetSecurityDescriptorDacl " \
"failed, status = 0x%lx\n",
Status));
goto ErrorExit;
}
if (pStatus != NULL) *pStatus = ERROR_SUCCESS;
return(pSecurityDescriptor);
ErrorExit:
for (i = 0; i < AceCount; i++)
{
if (rgAce[i] != NULL)
{
LocalFree(rgAce[i]);
rgAce[i] = NULL;
}
}
if (pAcl != NULL) LocalFree(pAcl);
if (pSecurityDescriptor != NULL) LocalFree(pSecurityDescriptor);
if (pStatus != NULL) *pStatus = Status;
return(NULL);
}
//+---------------------------------------------------------------------------
//
// Function: DeleteSecurityDescriptor
//
// Synopsis: Deallocate the security descriptor allocated in
// CreateSecurityDescriptor.
//
// Arguments: [pSecurityDescriptor] -- SD returned from
// CreateSecurityDescriptor.
//
// Returns: None.
//
// Notes: None.
//
//----------------------------------------------------------------------------
void
DeleteSecurityDescriptor(PSECURITY_DESCRIPTOR pSecurityDescriptor)
{
BOOL fPresent;
BOOL fDefaulted;
PACL pAcl;
schAssert(pSecurityDescriptor != NULL);
if (GetSecurityDescriptorDacl(pSecurityDescriptor,
&fPresent,
&pAcl,
&fDefaulted))
{
if (fPresent && pAcl != NULL)
{
LocalFree(pAcl);
}
}
else
{
schDebugOut((DEB_ERROR,
"DeleteSecurityDescriptor, GetSecurityDescriptorDacl failed, " \
"status = 0x%lx\n",
GetLastError()));
}
LocalFree(pSecurityDescriptor);
}
//+---------------------------------------------------------------------------
//
// Function: CreateAccessAllowedAce
//
// Synopsis: Scavenged code from winlogon to create an access allowed ACE.
// Modified a bit to use Win32 vs. Rtl.
//
// Arguments: [pSid] -- Sid to which this ACE is applied.
// [AccessMask] -- ACE access mask value.
// [AceFlags] -- ACE flags value.
// [InheritFlags] -- ACE inherit flags value.
//
// Returns: Created ACE if successful.
// NULL on error.
//
// Notes: None.
//
//----------------------------------------------------------------------------
PACCESS_ALLOWED_ACE
CreateAccessAllowedAce(
PSID pSid,
ACCESS_MASK AccessMask,
UCHAR AceFlags,
UCHAR InheritFlags,
DWORD * pStatus)
{
ULONG LengthSid = GetLengthSid(pSid);
ULONG LengthACE = sizeof(ACE_HEADER) + sizeof(ACCESS_MASK) + LengthSid;
PACCESS_ALLOWED_ACE Ace;
Ace = (PACCESS_ALLOWED_ACE)LocalAlloc(LMEM_FIXED, LengthACE);
if (Ace == NULL)
{
if (pStatus != NULL) *pStatus = ERROR_NOT_ENOUGH_MEMORY;
schDebugOut((DEB_ERROR,
"CreateAccessAllowedAce, ACE allocation failed\n"));
return(NULL);
}
Ace->Header.AceType = ACCESS_ALLOWED_ACE_TYPE;
Ace->Header.AceSize = (UCHAR)LengthACE;
Ace->Header.AceFlags = AceFlags | InheritFlags;
Ace->Mask = AccessMask;
CopySid(LengthSid, (PSID)(&(Ace->SidStart)), pSid);
if (pStatus != NULL) *pStatus = ERROR_SUCCESS;
return(Ace);
}
//+---------------------------------------------------------------------------
//
// Function: IsThreadCallerAnAdmin
//
// Synopsis: Determine if the user represented by the specified token is a
// member of the administrators group.
//
// Arguments: [hThreadToken] -- Token to check. If NULL, the current
// thread's token is used if there is one, or else the
// current process' token.
//
// Returns: TRUE -- Match
// FALSE -- Thread caller not an admin or an error occurred.
//
//----------------------------------------------------------------------------
BOOL
IsThreadCallerAnAdmin(HANDLE hThreadToken)
{
//
// Create an admin SID to compare against.
//
#if 1
//
// Efficient way - relies on the format of the SID structure (which is
// published in winnt.h) - valid for at least NT 4 and NT 5
//
schAssert(sizeof SID == 12);
const struct
{
SID Sid;
DWORD SubAuthority1;
} AdminSid =
{
{ SID_REVISION, // Revision
2, // SubAuthorityCount
SECURITY_NT_AUTHORITY, // IdentifierAuthority
SECURITY_BUILTIN_DOMAIN_RID }, // SubAuthority[0]
DOMAIN_ALIAS_RID_ADMINS // SubAuthority[1]
};
#else
/*
#error SID structure has changed!
//
// Inefficient way, initialize at run time
//
BYTE AdminSid[MAX_SID_SIZE];
SID_IDENTIFIER_AUTHORITY IdentifierAuthority = SECURITY_NT_AUTHORITY;
if (! InitializeSid(rgbAdminSid, &IdentifierAuthority, 2))
{
schAssert(0);
CHECK_HRESULT(HRESULT_FROM_WIN32(GetLastError()));
return FALSE;
}
*GetSidSubAuthority(rgbAdminSid, 0) = SECURITY_BUILTIN_DOMAIN_RID;
*GetSidSubAuthority(rgbAdminSid, 1) = DOMAIN_ALIAS_RID_ADMINS;
*/
#endif
//
// See if the token is a member.
//
BOOL fIsCallerAdmin;
if (!CheckTokenMembership(hThreadToken,
(PSID) &AdminSid,
&fIsCallerAdmin))
{
CHECK_HRESULT(HRESULT_FROM_WIN32(GetLastError()));
return FALSE;
}
return fIsCallerAdmin;
}