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Diffstat (limited to 'src/VBox/Runtime/common/asn1/asn1-safer-allocator.cpp')
| -rw-r--r-- | src/VBox/Runtime/common/asn1/asn1-safer-allocator.cpp | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/asn1/asn1-safer-allocator.cpp b/src/VBox/Runtime/common/asn1/asn1-safer-allocator.cpp new file mode 100644 index 00000000..e30e7041 --- /dev/null +++ b/src/VBox/Runtime/common/asn1/asn1-safer-allocator.cpp @@ -0,0 +1,222 @@ +/* $Id: asn1-safer-allocator.cpp $ */ +/** @file + * IPRT - ASN.1, Safer Allocator, for sensitive data. + */ + +/* + * Copyright (C) 2006-2019 Oracle Corporation + * + * This file is part of VirtualBox Open Source Edition (OSE), as + * available from http://www.virtualbox.org. This file is free software; + * you can redistribute it and/or modify it under the terms of the GNU + * General Public License (GPL) as published by the Free Software + * Foundation, in version 2 as it comes in the "COPYING" file of the + * VirtualBox OSE distribution. VirtualBox OSE is distributed in the + * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL) only, as it comes in the "COPYING.CDDL" file of the + * VirtualBox OSE distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include "internal/iprt.h" +#include <iprt/asn1.h> + +#include <iprt/memsafer.h> +#include <iprt/errcore.h> +#include <iprt/string.h> + + +/** + * Aligns allocation sizes a little. + * + * @returns Aligned size. + * @param cb Requested size. + */ +static size_t rtAsn1SaferAllocator_AlignSize(size_t cb) +{ + if (cb >= 64) + return RT_ALIGN_Z(cb, 64); + if (cb >= 32) + return RT_ALIGN_Z(cb, 32); + if (cb >= 16) + return RT_ALIGN_Z(cb, 16); + return cb; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnFree} */ +static DECLCALLBACK(void) rtAsn1SaferAllocator_Free(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ALLOCATION pAllocation, void *pv) +{ + RT_NOREF_PV(pThis); + RTMemSaferFree(pv, pAllocation->cbAllocated); + pAllocation->cbAllocated = 0; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnAlloc} */ +static DECLCALLBACK(int) rtAsn1SaferAllocator_Alloc(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ALLOCATION pAllocation, + void **ppv, size_t cb) +{ + size_t cbAlloc = rtAsn1SaferAllocator_AlignSize(cb); + void *pv = RTMemSaferAllocZ(cbAlloc); + if (pv) + { + *ppv = pv; + pAllocation->cbAllocated = (uint32_t)cbAlloc; + return VINF_SUCCESS; + } + RT_NOREF_PV(pThis); + return VERR_NO_MEMORY; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnRealloc} */ +static DECLCALLBACK(int) rtAsn1SaferAllocator_Realloc(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ALLOCATION pAllocation, + void *pvOld, void **ppvNew, size_t cbNew) +{ + Assert(pvOld); + Assert(cbNew); + size_t cbAlloc = rtAsn1SaferAllocator_AlignSize(cbNew); + void *pv = RTMemSaferReallocZ(pAllocation->cbAllocated, pvOld, cbAlloc); + if (pv) + { + *ppvNew = pv; + pAllocation->cbAllocated = (uint32_t)cbAlloc; + return VINF_SUCCESS; + } + RT_NOREF_PV(pThis); + return VERR_NO_MEMORY; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnFreeArray} */ +static DECLCALLBACK(void) rtAsn1SaferAllocator_FreeArray(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ARRAYALLOCATION pAllocation, + void **papvArray) +{ + RT_NOREF_PV(pThis); + Assert(papvArray); + Assert(pAllocation->cbEntry); + + uint32_t i = pAllocation->cEntriesAllocated; + while (i-- > 0) + RTMemSaferFree(papvArray[i], pAllocation->cbEntry); + RTMemFree(papvArray); + + pAllocation->cEntriesAllocated = 0; + pAllocation->cPointersAllocated = 0; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnGrowArray} */ +static DECLCALLBACK(int) rtAsn1SaferAllocator_GrowArray(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ARRAYALLOCATION pAllocation, + void ***ppapvArray, uint32_t cMinEntries) +{ + RT_NOREF_PV(pThis); + + /* + * Resize the pointer array. We do chunks of 64 bytes for now. + */ + void **papvArray = *ppapvArray; + uint32_t cPointers = RT_ALIGN_32(cMinEntries, 64 / sizeof(void *)); + if (cPointers > pAllocation->cPointersAllocated) + { + void *pvPointers = RTMemRealloc(papvArray, cPointers * sizeof(void *)); + if (pvPointers) + { /* likely */ } + else if (cMinEntries > pAllocation->cPointersAllocated) + { + cPointers = cMinEntries; + pvPointers = RTMemRealloc(*ppapvArray, cPointers * sizeof(void *)); + if (!pvPointers) + return VERR_NO_MEMORY; + } + else + { + cPointers = pAllocation->cPointersAllocated; + pvPointers = papvArray; + } + + *ppapvArray = papvArray = (void **)pvPointers; + RT_BZERO(&papvArray[pAllocation->cPointersAllocated], (cPointers - pAllocation->cPointersAllocated) * sizeof(void *)); + pAllocation->cPointersAllocated = cPointers; + } + + /* + * Add more entries. Do multiple as the array grows. + * + * Note! We could possibly optimize this by allocating slabs of entries and + * slice them up. However, keep things as simple as possible for now. + */ + uint32_t cEntries = cMinEntries; + if (cEntries > 2) + { + if (cEntries > 8) + cEntries = RT_ALIGN_32(cEntries, 4); + else + cEntries = RT_ALIGN_32(cEntries, 2); + cEntries = RT_MIN(cEntries, cPointers); + Assert(cEntries >= cMinEntries); + } + Assert(cEntries <= pAllocation->cPointersAllocated); + + while (pAllocation->cEntriesAllocated < cEntries) + { + void *pv; + papvArray[pAllocation->cEntriesAllocated] = pv = RTMemSaferAllocZ(pAllocation->cbEntry); + if (pv) + pAllocation->cEntriesAllocated++; + else if (pAllocation->cEntriesAllocated >= cMinEntries) + break; + else + return VERR_NO_MEMORY; + } + + return VINF_SUCCESS; +} + + +/** @interface_method_impl{RTASN1ALLOCATORVTABLE,pfnShrinkArray} */ +static DECLCALLBACK(void) rtAsn1SaferAllocator_ShrinkArray(PCRTASN1ALLOCATORVTABLE pThis, PRTASN1ARRAYALLOCATION pAllocation, + void ***ppapvArray, uint32_t cNew, uint32_t cCurrent) +{ + RT_NOREF_PV(pThis); + + /* + * For now we only zero the entries being removed. + */ + void **papvArray = *ppapvArray; + while (cNew < cCurrent) + { + RTMemWipeThoroughly(papvArray[cNew], pAllocation->cbEntry, 3); + RT_BZERO(papvArray[cNew], pAllocation->cbEntry); + cNew++; + } +} + + + +/** The Safer ASN.1 allocator. */ +#if 1 || !defined(IN_RING3) || defined(DOXYGEN_RUNNING) +RT_DECL_DATA_CONST(RTASN1ALLOCATORVTABLE const) g_RTAsn1SaferAllocator = +#else +RT_DECL_DATA_CONST(RTASN1ALLOCATORVTABLE const) g_RTAsn1SaferAllocatorDisabled = +#endif +{ + rtAsn1SaferAllocator_Free, + rtAsn1SaferAllocator_Alloc, + rtAsn1SaferAllocator_Realloc, + rtAsn1SaferAllocator_FreeArray, + rtAsn1SaferAllocator_GrowArray, + rtAsn1SaferAllocator_ShrinkArray +}; + |