diff options
| author | Sean Brogan <sean.brogan@microsoft.com> | 2017-04-24 16:37:20 -0700 |
|---|---|---|
| committer | Kinney, Michael D <michael.d.kinney@intel.com> | 2018-01-25 09:42:20 -0800 |
| commit | d7a09cb86a0416c099fa3a9e0fbe2c8f399b28de (patch) | |
| tree | c46f9e44097e63cf3dc2aa141ee98bbda599fc10 /MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c | |
| parent | 11cf02f6d0a56398023e01b0322fbd05a396b353 (diff) | |
| download | edk2-d7a09cb86a0416c099fa3a9e0fbe2c8f399b28de.tar.gz | |
MdePkg/BaseSafeIntLib: Add SafeIntLib class and instance
https://bugzilla.tianocore.org/show_bug.cgi?id=798
SafeIntLib provides helper functions to prevent integer overflow
during type conversion, addition, subtraction, and multiplication.
Conversion Functions
====================
* Converting from a signed type to an unsigned type of the same
size, or vice-versa.
* Converting to a smaller type that could possibly overflow.
* Converting from a signed type to a larger unsigned type.
Unsigned Addition, Subtraction, Multiplication
===============================================
* Unsigned integer math functions protect from overflow and
underflow (in case of subtraction).
Signed Addition, Subtraction, Multiplication
============================================
* Strongly consider using unsigned numbers.
* Signed numbers are often used where unsigned numbers should
be used. For example file sizes and array indices should always
be unsigned. Subtracting a larger positive signed number from a
smaller positive signed number with SafeInt32Sub() will succeed,
producing a negative number, that then must not be used as an
array index (but can occasionally be used as a pointer index.)
Similarly for adding a larger magnitude negative number to a
smaller magnitude positive number.
* SafeIntLib does not protect you from such errors. It tells you
if your integer operations overflowed, not if you are doing the
right thing with your non-overflowed integers.
* Likewise you can overflow a buffer with a non-overflowed
unsigned index.
Based on content from the following branch/commits:
https://github.com/Microsoft/MS_UEFI/tree/share/MsCapsuleSupport
https://github.com/Microsoft/MS_UEFI/commit/21ef3a321c907b40fa93797619c9f6c686dd92e0
https://github.com/Microsoft/MS_UEFI/commit/ca516b1a61315c2d823f453e12d2135098f53d61
https://github.com/Microsoft/MS_UEFI/commit/33bab4031a417d7d5a7d356c15a14c2e60302b2d
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Sean Brogan <sean.brogan@microsoft.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Diffstat (limited to 'MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c')
| -rw-r--r-- | MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c | 614 |
1 files changed, 614 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c b/MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c new file mode 100644 index 0000000000..4478957b7e --- /dev/null +++ b/MdePkg/Library/BaseSafeIntLib/SafeIntLibEbc.c @@ -0,0 +1,614 @@ +/** @file
+ This library provides helper functions to prevent integer overflow during
+ type conversion, addition, subtraction, and multiplication.
+
+ Copyright (c) 2017, Microsoft Corporation
+
+ All rights reserved.
+ 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 COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
+
+**/
+
+#include <Base.h>
+#include <Library/SafeIntLib.h>
+
+/**
+ INT32 -> UINTN conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeInt32ToUintn (
+ IN INT32 Operand,
+ OUT UINTN *Result
+ )
+{
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt32ToUint32 (Operand, (UINT32 *)Result);
+ }
+ return SafeInt32ToUint64 (Operand, (UINT64 *) Result);
+}
+
+/**
+ UINT32 -> INTN conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUint32ToIntn (
+ IN UINT32 Operand,
+ OUT INTN *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeUint32ToInt32 (Operand, (INT32 *)Result);
+ }
+ *Result = Operand;
+ return RETURN_SUCCESS;
+}
+
+/**
+ INTN -> INT32 conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to INT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeIntnToInt32 (
+ IN INTN Operand,
+ OUT INT32 *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ *Result = (INT32)Operand;
+ return RETURN_SUCCESS;
+ }
+ return SafeInt64ToInt32 ((INT64) Operand, Result);
+}
+
+/**
+ INTN -> UINT32 conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeIntnToUint32 (
+ IN INTN Operand,
+ OUT UINT32 *Result
+ )
+{
+ RETURN_STATUS Status;
+
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ if (Operand >= 0) {
+ *Result = (UINT32)Operand;
+ Status = RETURN_SUCCESS;
+ } else {
+ *Result = UINT32_ERROR;
+ Status = RETURN_BUFFER_TOO_SMALL;
+ }
+
+ return Status;
+ }
+ return SafeInt64ToUint32 ((INT64)Operand, Result);
+}
+
+/**
+ UINTN -> UINT32 conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to UINT32_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUintnToUint32 (
+ IN UINTN Operand,
+ OUT UINT32 *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ *Result = (UINT32)Operand;
+ return RETURN_SUCCESS;
+ }
+ return SafeUint64ToUint32 ((UINT64)Operand, Result);
+}
+
+/**
+ UINTN -> INT64 conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to INT64_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUintnToInt64 (
+ IN UINTN Operand,
+ OUT INT64 *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ *Result = (INT64)Operand;
+ return RETURN_SUCCESS;
+ }
+ return SafeUint64ToInt64 ((UINT64)Operand, Result);
+}
+
+/**
+ INT64 -> INTN conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeInt64ToIntn (
+ IN INT64 Operand,
+ OUT INTN *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt64ToInt32 (Operand, (INT32 *)Result);
+ }
+ *Result = (INTN)Operand;
+ return RETURN_SUCCESS;
+}
+
+/**
+ INT64 -> UINTN conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeInt64ToUintn (
+ IN INT64 Operand,
+ OUT UINTN *Result
+ )
+{
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt64ToUint32 (Operand, (UINT32 *)Result);
+ }
+ return SafeInt64ToUint64 (Operand, (UINT64 *)Result);
+}
+
+/**
+ UINT64 -> UINTN conversion
+
+ Converts the value specified by Operand to a value specified by Result type
+ and stores the converted value into the caller allocated output buffer
+ specified by Result. The caller must pass in a Result buffer that is at
+ least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the conversion results in an overflow or an underflow condition, then
+ Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Operand Operand to be converted to new type
+ @param[out] Result Pointer to the result of conversion
+
+ @retval RETURN_SUCCESS Successful conversion
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUint64ToUintn (
+ IN UINT64 Operand,
+ OUT UINTN *Result
+ )
+{
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeUint64ToUint32 ((UINT64) Operand, (UINT32 *)Result);
+ }
+ *Result = Operand;
+ return RETURN_SUCCESS;
+}
+
+/**
+ UINTN addition
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Augend A number to which addend will be added
+ @param[in] Addend A number to be added to another
+ @param[out] Result Pointer to the result of addition
+
+ @retval RETURN_SUCCESS Successful addition
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUintnAdd (
+ IN UINTN Augend,
+ IN UINTN Addend,
+ OUT UINTN *Result
+ )
+{
+ RETURN_STATUS Status;
+
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ if ((UINT32)(Augend + Addend) >= Augend) {
+ *Result = (Augend + Addend);
+ Status = RETURN_SUCCESS;
+ } else {
+ *Result = UINTN_ERROR;
+ Status = RETURN_BUFFER_TOO_SMALL;
+ }
+
+ return Status;
+ }
+ return SafeUint64Add ((UINT64)Augend, (UINT64)Addend, (UINT64 *)Result);
+}
+
+/**
+ UINTN subtraction
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Minuend A number from which another is to be subtracted.
+ @param[in] Subtrahend A number to be subtracted from another
+ @param[out] Result Pointer to the result of subtraction
+
+ @retval RETURN_SUCCESS Successful subtraction
+ @retval RETURN_BUFFER_TOO_SMALL Underflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUintnSub (
+ IN UINTN Minuend,
+ IN UINTN Subtrahend,
+ OUT UINTN *Result
+ )
+{
+ RETURN_STATUS Status;
+
+ if (Result == NULL) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ if (Minuend >= Subtrahend) {
+ *Result = (Minuend - Subtrahend);
+ Status = RETURN_SUCCESS;
+ } else {
+ *Result = UINTN_ERROR;
+ Status = RETURN_BUFFER_TOO_SMALL;
+ }
+
+ return Status;
+ }
+ return SafeUint64Sub ((UINT64)Minuend, (UINT64)Subtrahend, (UINT64 *)Result);
+}
+
+/**
+ UINTN multiplication
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to UINTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Multiplicand A number that is to be multiplied by another
+ @param[in] Multiplier A number by which the multiplicand is to be multiplied
+ @param[out] Result Pointer to the result of multiplication
+
+ @retval RETURN_SUCCESS Successful multiplication
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeUintnMult (
+ IN UINTN Multiplicand,
+ IN UINTN Multiplier,
+ OUT UINTN *Result
+ )
+{
+ UINT64 IntermediateResult;
+
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ IntermediateResult = ((UINT64) Multiplicand) *((UINT64) Multiplier);
+
+ return SafeUint64ToUintn (IntermediateResult, Result);
+ }
+ return SafeUint64Mult ((UINT64)Multiplicand, (UINT64)Multiplier, (UINT64 *)Result);
+}
+
+/**
+ INTN Addition
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Augend A number to which addend will be added
+ @param[in] Addend A number to be added to another
+ @param[out] Result Pointer to the result of addition
+
+ @retval RETURN_SUCCESS Successful addition
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeIntnAdd (
+ IN INTN Augend,
+ IN INTN Addend,
+ OUT INTN *Result
+ )
+{
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt64ToIntn (((INT64)Augend) + ((INT64)Addend), Result);
+ }
+ return SafeInt64Add ((INT64)Augend, (INT64)Addend, (INT64 *)Result);
+}
+
+/**
+ INTN Subtraction
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Minuend A number from which another is to be subtracted.
+ @param[in] Subtrahend A number to be subtracted from another
+ @param[out] Result Pointer to the result of subtraction
+
+ @retval RETURN_SUCCESS Successful subtraction
+ @retval RETURN_BUFFER_TOO_SMALL Underflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeIntnSub (
+ IN INTN Minuend,
+ IN INTN Subtrahend,
+ OUT INTN *Result
+ )
+{
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt64ToIntn (((INT64)Minuend) - ((INT64)Subtrahend), Result);
+ }
+ return SafeInt64Sub ((INT64)Minuend, (INT64)Subtrahend, (INT64 *)Result);
+}
+
+/**
+ INTN multiplication
+
+ Performs the requested operation using the input parameters into a value
+ specified by Result type and stores the converted value into the caller
+ allocated output buffer specified by Result. The caller must pass in a
+ Result buffer that is at least as large as the Result type.
+
+ If Result is NULL, RETURN_INVALID_PARAMETER is returned.
+
+ If the requested operation results in an overflow or an underflow condition,
+ then Result is set to INTN_ERROR and RETURN_BUFFER_TOO_SMALL is returned.
+
+ @param[in] Multiplicand A number that is to be multiplied by another
+ @param[in] Multiplier A number by which the multiplicand is to be multiplied
+ @param[out] Result Pointer to the result of multiplication
+
+ @retval RETURN_SUCCESS Successful multiplication
+ @retval RETURN_BUFFER_TOO_SMALL Overflow
+ @retval RETURN_INVALID_PARAMETER Result is NULL
+**/
+RETURN_STATUS
+EFIAPI
+SafeIntnMult (
+ IN INTN Multiplicand,
+ IN INTN Multiplier,
+ OUT INTN *Result
+ )
+{
+ if (sizeof (UINTN) == sizeof (UINT32)) {
+ return SafeInt64ToIntn (((INT64)Multiplicand) *((INT64)Multiplier), Result);
+ }
+ return SafeInt64Mult ((INT64)Multiplicand, (INT64)Multiplier, (INT64 *)Result);
+}
+
|