FreeRDP/libfreerdp/crypto/ber.c
2024-02-15 11:49:16 +01:00

733 lines
15 KiB
C

/**
* FreeRDP: A Remote Desktop Protocol Implementation
* ASN.1 Basic Encoding Rules (BER)
*
* Copyright 2011-2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <freerdp/config.h>
#include <stdio.h>
#include <winpr/assert.h>
#include <winpr/crt.h>
#include <winpr/string.h>
#include <freerdp/log.h>
#include <freerdp/crypto/ber.h>
#define TAG FREERDP_TAG("crypto")
BOOL ber_read_length(wStream* s, size_t* length)
{
BYTE byte;
WINPR_ASSERT(s);
WINPR_ASSERT(length);
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, byte);
if (byte & 0x80)
{
byte &= ~(0x80);
if (!Stream_CheckAndLogRequiredLength(TAG, s, byte))
return FALSE;
if (byte == 1)
Stream_Read_UINT8(s, *length);
else if (byte == 2)
Stream_Read_UINT16_BE(s, *length);
else
{
WLog_ERR(TAG, "ber: unexpected byte 0x%02" PRIx8 ", expected [1,2]", byte);
return FALSE;
}
}
else
{
*length = byte;
}
return TRUE;
}
/**
* Write BER length.
* @param s stream
* @param length length
*/
size_t ber_write_length(wStream* s, size_t length)
{
WINPR_ASSERT(s);
if (length > 0xFF)
{
WINPR_ASSERT(length <= UINT16_MAX);
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 3);
Stream_Write_UINT8(s, 0x80 ^ 2);
Stream_Write_UINT16_BE(s, (UINT16)length);
return 3;
}
WINPR_ASSERT(length <= UINT8_MAX);
if (length > 0x7F)
{
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 2);
Stream_Write_UINT8(s, 0x80 ^ 1);
Stream_Write_UINT8(s, (UINT8)length);
return 2;
}
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 1);
Stream_Write_UINT8(s, (UINT8)length);
return 1;
}
size_t _ber_sizeof_length(size_t length)
{
if (length > 0xFF)
return 3;
if (length > 0x7F)
return 2;
return 1;
}
/**
* Read BER Universal tag.
*
* @param s The stream to read from
* @param tag BER universally-defined tag
*
* @return \b TRUE for success, \b FALSE otherwise
*/
BOOL ber_read_universal_tag(wStream* s, BYTE tag, BOOL pc)
{
BYTE byte;
const BYTE expect = (BER_CLASS_UNIV | BER_PC(pc) | (BER_TAG_MASK & tag));
WINPR_ASSERT(s);
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, byte);
if (byte != expect)
{
WLog_WARN(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, expect);
return FALSE;
}
return TRUE;
}
/**
* Write BER Universal tag.
* @param s stream
* @param tag BER universally-defined tag
* @param pc primitive (FALSE) or constructed (TRUE)
*/
size_t ber_write_universal_tag(wStream* s, BYTE tag, BOOL pc)
{
WINPR_ASSERT(s);
Stream_Write_UINT8(s, (BER_CLASS_UNIV | BER_PC(pc)) | (BER_TAG_MASK & tag));
return 1;
}
/**
* Read BER Application tag.
* @param s stream
* @param tag BER application-defined tag
* @param length length
*/
BOOL ber_read_application_tag(wStream* s, BYTE tag, size_t* length)
{
BYTE byte;
WINPR_ASSERT(s);
WINPR_ASSERT(length);
if (tag > 30)
{
const BYTE expect = ((BER_CLASS_APPL | BER_CONSTRUCT) | BER_TAG_MASK);
if (!Stream_CheckAndLogRequiredLength(TAG, s, 2))
return FALSE;
Stream_Read_UINT8(s, byte);
if (byte != expect)
{
WLog_WARN(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, expect);
return FALSE;
}
Stream_Read_UINT8(s, byte);
if (byte != tag)
{
WLog_WARN(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, tag);
return FALSE;
}
return ber_read_length(s, length);
}
else
{
const BYTE expect = ((BER_CLASS_APPL | BER_CONSTRUCT) | (BER_TAG_MASK & tag));
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, byte);
if (byte != expect)
{
WLog_WARN(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, expect);
return FALSE;
}
return ber_read_length(s, length);
}
return TRUE;
}
/**
* Write BER Application tag.
* @param s stream
* @param tag BER application-defined tag
* @param length length
*/
void ber_write_application_tag(wStream* s, BYTE tag, size_t length)
{
WINPR_ASSERT(s);
if (tag > 30)
{
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 2);
Stream_Write_UINT8(s, (BER_CLASS_APPL | BER_CONSTRUCT) | BER_TAG_MASK);
Stream_Write_UINT8(s, tag);
ber_write_length(s, length);
}
else
{
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 1);
Stream_Write_UINT8(s, (BER_CLASS_APPL | BER_CONSTRUCT) | (BER_TAG_MASK & tag));
ber_write_length(s, length);
}
}
BOOL ber_read_contextual_tag(wStream* s, BYTE tag, size_t* length, BOOL pc)
{
const BYTE expect = ((BER_CLASS_CTXT | BER_PC(pc)) | (BER_TAG_MASK & tag));
BYTE byte;
WINPR_ASSERT(s);
WINPR_ASSERT(length);
if (Stream_GetRemainingLength(s) < 1)
{
WLog_VRB(TAG, "short data, got %" PRIuz ", expected %" PRIuz, Stream_GetRemainingLength(s),
1);
return FALSE;
}
Stream_Read_UINT8(s, byte);
if (byte != expect)
{
WLog_VRB(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, expect);
Stream_Rewind(s, 1);
return FALSE;
}
return ber_read_length(s, length);
}
size_t ber_write_contextual_tag(wStream* s, BYTE tag, size_t length, BOOL pc)
{
WINPR_ASSERT(s);
WINPR_ASSERT(Stream_GetRemainingCapacity(s) >= 1);
Stream_Write_UINT8(s, (BER_CLASS_CTXT | BER_PC(pc)) | (BER_TAG_MASK & tag));
return 1 + ber_write_length(s, length);
}
size_t ber_sizeof_contextual_tag(size_t length)
{
return 1 + _ber_sizeof_length(length);
}
BOOL ber_read_sequence_tag(wStream* s, size_t* length)
{
const BYTE expect = ((BER_CLASS_UNIV | BER_CONSTRUCT) | (BER_TAG_SEQUENCE_OF));
BYTE byte;
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, byte);
if (byte != expect)
{
WLog_WARN(TAG, "invalid tag, got 0x%02" PRIx8 ", expected 0x%02" PRIx8, byte, expect);
return FALSE;
}
return ber_read_length(s, length);
}
/**
* Write BER SEQUENCE tag.
* @param s stream
* @param length length
*/
size_t ber_write_sequence_tag(wStream* s, size_t length)
{
Stream_Write_UINT8(s, (BER_CLASS_UNIV | BER_CONSTRUCT) | (BER_TAG_MASK & BER_TAG_SEQUENCE));
return 1 + ber_write_length(s, length);
}
size_t ber_sizeof_sequence(size_t length)
{
return 1 + _ber_sizeof_length(length) + length;
}
size_t ber_sizeof_sequence_tag(size_t length)
{
return 1 + _ber_sizeof_length(length);
}
BOOL ber_read_enumerated(wStream* s, BYTE* enumerated, BYTE count)
{
size_t length;
WINPR_ASSERT(enumerated);
if (!ber_read_universal_tag(s, BER_TAG_ENUMERATED, FALSE) || !ber_read_length(s, &length))
return FALSE;
if (length != 1)
{
WLog_WARN(TAG, "short data, got %" PRIuz ", expected %" PRIuz, length, 1);
return FALSE;
}
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, *enumerated);
/* check that enumerated value falls within expected range */
if (*enumerated + 1 > count)
{
WLog_WARN(TAG, "invalid data, expected %" PRIu8 " < %" PRIu8, *enumerated, count);
return FALSE;
}
return TRUE;
}
void ber_write_enumerated(wStream* s, BYTE enumerated, BYTE count)
{
ber_write_universal_tag(s, BER_TAG_ENUMERATED, FALSE);
ber_write_length(s, 1);
Stream_Write_UINT8(s, enumerated);
}
BOOL ber_read_bit_string(wStream* s, size_t* length, BYTE* padding)
{
if (!ber_read_universal_tag(s, BER_TAG_BIT_STRING, FALSE) || !ber_read_length(s, length))
return FALSE;
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, *padding);
return TRUE;
}
/**
* Write a BER OCTET_STRING
* @param s stream
* @param oct_str octet string
* @param length string length
*/
size_t ber_write_octet_string(wStream* s, const BYTE* oct_str, size_t length)
{
size_t size = 0;
WINPR_ASSERT(oct_str || (length == 0));
size += ber_write_universal_tag(s, BER_TAG_OCTET_STRING, FALSE);
size += ber_write_length(s, length);
Stream_Write(s, oct_str, length);
size += length;
return size;
}
size_t ber_write_contextual_octet_string(wStream* s, BYTE tag, const BYTE* oct_str, size_t length)
{
size_t inner = ber_sizeof_octet_string(length);
size_t ret;
size_t r;
ret = ber_write_contextual_tag(s, tag, inner, TRUE);
if (!ret)
return 0;
r = ber_write_octet_string(s, oct_str, length);
if (!r)
return 0;
return ret + r;
}
size_t ber_write_char_to_unicode_octet_string(wStream* s, const char* str)
{
WINPR_ASSERT(str);
size_t size = 0;
size_t length = strlen(str) + 1;
size += ber_write_universal_tag(s, BER_TAG_OCTET_STRING, FALSE);
size += ber_write_length(s, length * sizeof(WCHAR));
if (Stream_Write_UTF16_String_From_UTF8(s, length, str, length, TRUE) < 0)
return 0;
return size + length * sizeof(WCHAR);
}
size_t ber_write_contextual_unicode_octet_string(wStream* s, BYTE tag, LPWSTR str)
{
WINPR_ASSERT(str);
size_t len = _wcslen(str) * sizeof(WCHAR);
size_t inner_len = ber_sizeof_octet_string(len);
size_t ret;
ret = ber_write_contextual_tag(s, tag, inner_len, TRUE);
return ret + ber_write_octet_string(s, (const BYTE*)str, len);
}
size_t ber_write_contextual_char_to_unicode_octet_string(wStream* s, BYTE tag, const char* str)
{
size_t ret;
size_t len = strlen(str);
size_t inner_len = ber_sizeof_octet_string(len * 2);
WINPR_ASSERT(Stream_GetRemainingCapacity(s) < ber_sizeof_contextual_tag(inner_len) + inner_len);
ret = ber_write_contextual_tag(s, tag, inner_len, TRUE);
ret += ber_write_universal_tag(s, BER_TAG_OCTET_STRING, FALSE);
ret += ber_write_length(s, len * sizeof(WCHAR));
if (Stream_Write_UTF16_String_From_UTF8(s, len, str, len, TRUE) < 0)
return 0;
return ret + len;
}
BOOL ber_read_unicode_octet_string(wStream* s, LPWSTR* str)
{
LPWSTR ret = NULL;
size_t length;
if (!ber_read_octet_string_tag(s, &length))
return FALSE;
if (!Stream_CheckAndLogRequiredLength(TAG, s, length))
return FALSE;
ret = calloc(1, length + 2);
if (!ret)
return FALSE;
memcpy(ret, Stream_ConstPointer(s), length);
ret[length / 2] = 0;
Stream_Seek(s, length);
*str = ret;
return TRUE;
}
BOOL ber_read_char_from_unicode_octet_string(wStream* s, char** str)
{
size_t length;
char* ptr;
*str = NULL;
if (!ber_read_octet_string_tag(s, &length))
return FALSE;
ptr = Stream_Read_UTF16_String_As_UTF8(s, length / sizeof(WCHAR), NULL);
if (!ptr)
return FALSE;
*str = ptr;
return TRUE;
}
BOOL ber_read_octet_string_tag(wStream* s, size_t* length)
{
return ber_read_universal_tag(s, BER_TAG_OCTET_STRING, FALSE) && ber_read_length(s, length);
}
BOOL ber_read_octet_string(wStream* s, BYTE** content, size_t* length)
{
BYTE* ret;
WINPR_ASSERT(s);
WINPR_ASSERT(content);
WINPR_ASSERT(length);
if (!ber_read_octet_string_tag(s, length))
return FALSE;
if (!Stream_CheckAndLogRequiredLength(TAG, s, *length))
return FALSE;
ret = malloc(*length);
if (!ret)
return FALSE;
Stream_Read(s, ret, *length);
*content = ret;
return TRUE;
}
size_t ber_write_octet_string_tag(wStream* s, size_t length)
{
ber_write_universal_tag(s, BER_TAG_OCTET_STRING, FALSE);
ber_write_length(s, length);
return 1 + _ber_sizeof_length(length);
}
size_t ber_sizeof_octet_string(size_t length)
{
return 1 + _ber_sizeof_length(length) + length;
}
size_t ber_sizeof_contextual_octet_string(size_t length)
{
size_t ret = ber_sizeof_octet_string(length);
return ber_sizeof_contextual_tag(ret) + ret;
}
/** \brief Read a BER BOOLEAN
*
* @param s The stream to read from.
* @param value A pointer to the value read, must not be NULL
*
* \return \b TRUE for success, \b FALSE for any failure
*/
BOOL ber_read_BOOL(wStream* s, BOOL* value)
{
size_t length;
BYTE v;
WINPR_ASSERT(value);
if (!ber_read_universal_tag(s, BER_TAG_BOOLEAN, FALSE) || !ber_read_length(s, &length))
return FALSE;
if (length != 1)
{
WLog_WARN(TAG, "short data, got %" PRIuz ", expected %" PRIuz, length, 1);
return FALSE;
}
if (!Stream_CheckAndLogRequiredLength(TAG, s, 1))
return FALSE;
Stream_Read_UINT8(s, v);
*value = (v ? TRUE : FALSE);
return TRUE;
}
/**
* Write a BER BOOLEAN
*
* @param s A pointer to the stream to write to
* @param value The value to write
*/
void ber_write_BOOL(wStream* s, BOOL value)
{
ber_write_universal_tag(s, BER_TAG_BOOLEAN, FALSE);
ber_write_length(s, 1);
Stream_Write_UINT8(s, (value == TRUE) ? 0xFF : 0);
}
BOOL ber_read_integer(wStream* s, UINT32* value)
{
size_t length;
WINPR_ASSERT(s);
if (!ber_read_universal_tag(s, BER_TAG_INTEGER, FALSE))
return FALSE;
if (!ber_read_length(s, &length))
return FALSE;
if (!Stream_CheckAndLogRequiredLength(TAG, s, length))
return FALSE;
if (value == NULL)
{
// even if we don't care the integer value, check the announced size
return Stream_SafeSeek(s, length);
}
if (length == 1)
{
Stream_Read_UINT8(s, *value);
}
else if (length == 2)
{
Stream_Read_UINT16_BE(s, *value);
}
else if (length == 3)
{
BYTE byte;
Stream_Read_UINT8(s, byte);
Stream_Read_UINT16_BE(s, *value);
*value += (byte << 16);
}
else if (length == 4)
{
Stream_Read_UINT32_BE(s, *value);
}
else if (length == 8)
{
WLog_ERR(TAG, "should implement reading an 8 bytes integer");
return FALSE;
}
else
{
WLog_ERR(TAG, "should implement reading an integer with length=%" PRIuz, length);
return FALSE;
}
return TRUE;
}
/**
* Write a BER INTEGER
*
* @param s A pointer to the stream to write to
* @param value The value to write
*
* @return The size in bytes that were written
*/
size_t ber_write_integer(wStream* s, UINT32 value)
{
WINPR_ASSERT(s);
if (value < 0x80)
{
ber_write_universal_tag(s, BER_TAG_INTEGER, FALSE);
ber_write_length(s, 1);
Stream_Write_UINT8(s, value);
return 3;
}
else if (value < 0x8000)
{
ber_write_universal_tag(s, BER_TAG_INTEGER, FALSE);
ber_write_length(s, 2);
Stream_Write_UINT16_BE(s, value);
return 4;
}
else if (value < 0x800000)
{
ber_write_universal_tag(s, BER_TAG_INTEGER, FALSE);
ber_write_length(s, 3);
Stream_Write_UINT8(s, (value >> 16));
Stream_Write_UINT16_BE(s, (value & 0xFFFF));
return 5;
}
else if (value < 0x80000000)
{
ber_write_universal_tag(s, BER_TAG_INTEGER, FALSE);
ber_write_length(s, 4);
Stream_Write_UINT32_BE(s, value);
return 6;
}
else
{
/* treat as signed integer i.e. NT/HRESULT error codes */
ber_write_universal_tag(s, BER_TAG_INTEGER, FALSE);
ber_write_length(s, 4);
Stream_Write_UINT32_BE(s, value);
return 6;
}
}
size_t ber_write_contextual_integer(wStream* s, BYTE tag, UINT32 value)
{
size_t len = ber_sizeof_integer(value);
WINPR_ASSERT(s);
WINPR_ASSERT(Stream_EnsureRemainingCapacity(s, len + 5));
len += ber_write_contextual_tag(s, tag, len, TRUE);
ber_write_integer(s, value);
return len;
}
size_t ber_sizeof_integer(UINT32 value)
{
if (value < 0x80)
{
return 3;
}
else if (value < 0x8000)
{
return 4;
}
else if (value < 0x800000)
{
return 5;
}
else if (value < 0x80000000)
{
return 6;
}
else
{
/* treat as signed integer i.e. NT/HRESULT error codes */
return 6;
}
}
size_t ber_sizeof_contextual_integer(UINT32 value)
{
size_t intSize = ber_sizeof_integer(value);
return ber_sizeof_contextual_tag(intSize) + intSize;
}
BOOL ber_read_integer_length(wStream* s, size_t* length)
{
return ber_read_universal_tag(s, BER_TAG_INTEGER, FALSE) && ber_read_length(s, length);
}