X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/27d06e044795c0b0ea4d34b10bccfa41d57f77fc..0bb514502a1d80e9b023d0e8a379f3559798eec2:/client/tinycbor/cborvalidation.c diff --git a/client/tinycbor/cborvalidation.c b/client/tinycbor/cborvalidation.c new file mode 100644 index 00000000..08c35117 --- /dev/null +++ b/client/tinycbor/cborvalidation.c @@ -0,0 +1,666 @@ +/**************************************************************************** +** +** Copyright (C) 2017 Intel Corporation +** +** Permission is hereby granted, free of charge, to any person obtaining a copy +** of this software and associated documentation files (the "Software"), to deal +** in the Software without restriction, including without limitation the rights +** to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +** copies of the Software, and to permit persons to whom the Software is +** furnished to do so, subject to the following conditions: +** +** The above copyright notice and this permission notice shall be included in +** all copies or substantial portions of the Software. +** +** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +** IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +** FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +** AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +** OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +** THE SOFTWARE. +** +****************************************************************************/ + +#define _BSD_SOURCE 1 +#define _DEFAULT_SOURCE 1 +#ifndef __STDC_LIMIT_MACROS +# define __STDC_LIMIT_MACROS 1 +#endif + +#include "cbor.h" +#include "cborinternal_p.h" +#include "compilersupport_p.h" +#include "utf8_p.h" + +#include + +#ifndef CBOR_NO_FLOATING_POINT +# include +# include +#endif + + +#ifndef CBOR_PARSER_MAX_RECURSIONS +# define CBOR_PARSER_MAX_RECURSIONS 1024 +#endif + +/** + * \addtogroup CborParsing + * @{ + */ + +/** + * \enum CborValidationFlags + * The CborValidationFlags enum contains flags that control the validation of a + * CBOR stream. + * + * \value CborValidateBasic Validates only the syntactic correctedness of the stream. + * \value CborValidateCanonical Validates that the stream is in canonical format, according to + * RFC 7049 section 3.9. + * \value CborValidateStrictMode Performs strict validation, according to RFC 7049 section 3.10. + * \value CborValidateStrictest Attempt to perform the strictest validation we know of. + * + * \value CborValidateShortestIntegrals (Canonical) Validate that integral numbers and lengths are + * enconded in their shortest form possible. + * \value CborValidateShortestFloatingPoint (Canonical) Validate that floating-point numbers are encoded + * in their shortest form possible. + * \value CborValidateShortestNumbers (Canonical) Validate both integral and floating-point numbers + * are in their shortest form possible. + * \value CborValidateNoIndeterminateLength (Canonical) Validate that no string, array or map uses + * indeterminate length encoding. + * \value CborValidateMapIsSorted (Canonical & Strict mode) Validate that map keys appear in + * sorted order. + * \value CborValidateMapKeysAreUnique (Strict mode) Validate that map keys are unique. + * \value CborValidateTagUse (Strict mode) Validate that known tags are used with the + * correct types. This does not validate that the content of + * those types is syntactically correct. For example, this + * option validates that tag 1 (DateTimeString) is used with + * a Text String, but it does not validate that the string is + * a valid date/time representation. + * \value CborValidateUtf8 (Strict mode) Validate that text strings are appropriately + * encoded in UTF-8. + * \value CborValidateMapKeysAreString Validate that all map keys are text strings. + * \value CborValidateNoUndefined Validate that no elements of type "undefined" are present. + * \value CborValidateNoTags Validate that no tags are used. + * \value CborValidateFiniteFloatingPoint Validate that all floating point numbers are finite (no NaN or + * infinities are allowed). + * \value CborValidateCompleteData Validate that the stream is complete and there is no more data + * in the buffer. + * \value CborValidateNoUnknownSimpleTypesSA Validate that all Standards Action simple types are registered + * with IANA. + * \value CborValidateNoUnknownSimpleTypes Validate that all simple types used are registered with IANA. + * \value CborValidateNoUnknownTagsSA Validate that all Standard Actions tags are registered with IANA. + * \value CborValidateNoUnknownTagsSR Validate that all Standard Actions and Specification Required tags + * are registered with IANA (see below for limitations). + * \value CborValidateNoUnkonwnTags Validate that all tags are registered with IANA + * (see below for limitations). + * + * \par Simple type registry + * The CBOR specification requires that registration for use of the first 19 + * simple types must be done by way of Standards Action. The rest of the simple + * types only require a specification. The official list can be obtained from + * https://www.iana.org/assignments/cbor-simple-values/cbor-simple-values.xhtml. + * + * \par + * There are no registered simple types recognized by this release of TinyCBOR + * (beyond those defined by RFC 7049). + * + * \par Tag registry + * The CBOR specification requires that registration for use of the first 23 + * tags must be done by way of Standards Action. The next up to tag 255 only + * require a specification. Finally, all other tags can be registered on a + * first-come-first-serve basis. The official list can be ontained from + * https://www.iana.org/assignments/cbor-tags/cbor-tags.xhtml. + * + * \par + * Given the variability of this list, TinyCBOR cannot recognize all tags + * registered with IANA. Instead, the implementation only recognizes tags + * that are backed by an RFC. + * + * \par + * These are the tags known to the current TinyCBOR release: + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
TagData ItemSemantics
0UTF-8 text stringStandard date/time string
1integerEpoch-based date/time
2byte stringPositive bignum
3byte stringNegative bignum
4arrayDecimal fraction
5arrayBigfloat
16arrayCOSE Single Recipient Encrypted Data Object (RFC 8152)
17arrayCOSE Mac w/o Recipients Object (RFC 8152)
18arrayCOSE Single Signer Data Object (RFC 8162)
21byte string, array, mapExpected conversion to base64url encoding
22byte string, array, mapExpected conversion to base64 encoding
23byte string, array, mapExpected conversion to base16 encoding
24byte stringEncoded CBOR data item
32UTF-8 text stringURI
33UTF-8 text stringbase64url
34UTF-8 text stringbase64
35UTF-8 text stringRegular expression
36UTF-8 text stringMIME message
96arrayCOSE Encrypted Data Object (RFC 8152)
97arrayCOSE MACed Data Object (RFC 8152)
98arrayCOSE Signed Data Object (RFC 8152)
55799anySelf-describe CBOR
+ */ + +struct KnownTagData { uint32_t tag; uint32_t types; }; +static const struct KnownTagData knownTagData[] = { + { 0, (uint32_t)CborTextStringType }, + { 1, (uint32_t)(CborIntegerType+1) }, + { 2, (uint32_t)CborByteStringType }, + { 3, (uint32_t)CborByteStringType }, + { 4, (uint32_t)CborArrayType }, + { 5, (uint32_t)CborArrayType }, + { 16, (uint32_t)CborArrayType }, + { 17, (uint32_t)CborArrayType }, + { 18, (uint32_t)CborArrayType }, + { 21, (uint32_t)CborByteStringType | ((uint32_t)CborArrayType << 8) | ((uint32_t)CborMapType << 16) }, + { 22, (uint32_t)CborByteStringType | ((uint32_t)CborArrayType << 8) | ((uint32_t)CborMapType << 16) }, + { 23, (uint32_t)CborByteStringType | ((uint32_t)CborArrayType << 8) | ((uint32_t)CborMapType << 16) }, + { 24, (uint32_t)CborByteStringType }, + { 32, (uint32_t)CborTextStringType }, + { 33, (uint32_t)CborTextStringType }, + { 34, (uint32_t)CborTextStringType }, + { 35, (uint32_t)CborTextStringType }, + { 36, (uint32_t)CborTextStringType }, + { 96, (uint32_t)CborArrayType }, + { 97, (uint32_t)CborArrayType }, + { 98, (uint32_t)CborArrayType }, + { 55799, 0U } +}; + +static CborError validate_value(CborValue *it, uint32_t flags, int recursionLeft); + +static inline CborError validate_utf8_string(const void *ptr, size_t n) +{ + const uint8_t *buffer = (const uint8_t *)ptr; + const uint8_t * const end = buffer + n; + while (buffer < end) { + uint32_t uc = get_utf8(&buffer, end); + if (uc == ~0U) + return CborErrorInvalidUtf8TextString; + } + return CborNoError; +} + +static inline CborError validate_simple_type(uint8_t simple_type, uint32_t flags) +{ + /* At current time, all known simple types are those from RFC 7049, + * which are parsed by the parser into different CBOR types. + * That means that if we've got here, the type is unknown */ + if (simple_type < 32) + return (flags & CborValidateNoUnknownSimpleTypesSA) ? CborErrorUnknownSimpleType : CborNoError; + return (flags & CborValidateNoUnknownSimpleTypes) == CborValidateNoUnknownSimpleTypes ? + CborErrorUnknownSimpleType : CborNoError; +} + +static inline CborError validate_number(const CborValue *it, CborType type, uint32_t flags) +{ + CborError err = CborNoError; + const uint8_t *ptr = it->ptr; + size_t bytesUsed, bytesNeeded; + uint64_t value; + + if ((flags & CborValidateShortestIntegrals) == 0) + return err; + if (type >= CborHalfFloatType && type <= CborDoubleType) + return err; /* checked elsewhere */ + + err = _cbor_value_extract_number(&ptr, it->parser->end, &value); + if (err) + return err; + + bytesUsed = (size_t)(ptr - it->ptr - 1); + bytesNeeded = 0; + if (value >= Value8Bit) + ++bytesNeeded; + if (value > 0xffU) + ++bytesNeeded; + if (value > 0xffffU) + bytesNeeded += 2; + if (value > 0xffffffffU) + bytesNeeded += 4; + if (bytesNeeded < bytesUsed) + return CborErrorOverlongEncoding; + return CborNoError; +} + +static inline CborError validate_tag(CborValue *it, CborTag tag, uint32_t flags, int recursionLeft) +{ + CborType type = cbor_value_get_type(it); + const size_t knownTagCount = sizeof(knownTagData) / sizeof(knownTagData[0]); + const struct KnownTagData *tagData = knownTagData; + const struct KnownTagData * const knownTagDataEnd = knownTagData + knownTagCount; + + if (!recursionLeft) + return CborErrorNestingTooDeep; + if (flags & CborValidateNoTags) + return CborErrorExcludedType; + + /* find the tag data, if any */ + for ( ; tagData != knownTagDataEnd; ++tagData) { + if (tagData->tag < tag) + continue; + if (tagData->tag > tag) + tagData = NULL; + break; + } + if (tagData == knownTagDataEnd) + tagData = NULL; + + if (flags & CborValidateNoUnknownTags && !tagData) { + /* tag not found */ + if (flags & CborValidateNoUnknownTagsSA && tag < 24) + return CborErrorUnknownTag; + if ((flags & CborValidateNoUnknownTagsSR) == CborValidateNoUnknownTagsSR && tag < 256) + return CborErrorUnknownTag; + if ((flags & CborValidateNoUnknownTags) == CborValidateNoUnknownTags) + return CborErrorUnknownTag; + } + + if (flags & CborValidateTagUse && tagData && tagData->types) { + uint32_t allowedTypes = tagData->types; + + /* correct Integer so it's not zero */ + if (type == CborIntegerType) + type = (CborType)(type + 1); + + while (allowedTypes) { + if ((uint8_t)(allowedTypes & 0xff) == type) + break; + allowedTypes >>= 8; + } + if (!allowedTypes) + return CborErrorInappropriateTagForType; + } + + return validate_value(it, flags, recursionLeft); +} + +#ifndef CBOR_NO_FLOATING_POINT +static inline CborError validate_floating_point(CborValue *it, CborType type, uint32_t flags) +{ + CborError err; + int r; + double val; + float valf; + uint16_t valf16; + + if (type != CborDoubleType) { + if (type == CborFloatType) { + err = cbor_value_get_float(it, &valf); + val = valf; + } else { +# ifdef CBOR_NO_HALF_FLOAT_TYPE + (void)valf16; + return CborErrorUnsupportedType; +# else + err = cbor_value_get_half_float(it, &valf16); + val = decode_half(valf16); +# endif + } + } else { + err = cbor_value_get_double(it, &val); + } + cbor_assert(err == CborNoError); /* can't fail */ + + r = fpclassify(val); + if (r == FP_NAN || r == FP_INFINITE) { + if (flags & CborValidateFiniteFloatingPoint) + return CborErrorExcludedValue; + if (flags & CborValidateShortestFloatingPoint) { + if (type == CborDoubleType) + return CborErrorOverlongEncoding; +# ifndef CBOR_NO_HALF_FLOAT_TYPE + if (type == CborFloatType) + return CborErrorOverlongEncoding; + if (r == FP_NAN && valf16 != 0x7e00) + return CborErrorImproperValue; + if (r == FP_INFINITE && valf16 != 0x7c00 && valf16 != 0xfc00) + return CborErrorImproperValue; +# endif + } + } + + if (flags & CborValidateShortestFloatingPoint && type > CborHalfFloatType) { + if (type == CborDoubleType) { + valf = (float)val; + if ((double)valf == val) + return CborErrorOverlongEncoding; + } +# ifndef CBOR_NO_HALF_FLOAT_TYPE + if (type == CborFloatType) { + valf16 = encode_half(valf); + if (valf == decode_half(valf16)) + return CborErrorOverlongEncoding; + } +# endif + } + + return CborNoError; +} +#endif + +static CborError validate_container(CborValue *it, int containerType, uint32_t flags, int recursionLeft) +{ + CborError err; + const uint8_t *previous = NULL; + const uint8_t *previous_end = NULL; + + if (!recursionLeft) + return CborErrorNestingTooDeep; + + while (!cbor_value_at_end(it)) { + const uint8_t *current = cbor_value_get_next_byte(it); + + if (containerType == CborMapType) { + if (flags & CborValidateMapKeysAreString) { + CborType type = cbor_value_get_type(it); + if (type == CborTagType) { + /* skip the tags */ + CborValue copy = *it; + err = cbor_value_skip_tag(©); + if (err) + return err; + type = cbor_value_get_type(©); + } + if (type != CborTextStringType) + return CborErrorMapKeyNotString; + } + } + + err = validate_value(it, flags, recursionLeft); + if (err) + return err; + + if (containerType != CborMapType) + continue; + + if (flags & CborValidateMapIsSorted) { + if (previous) { + uint64_t len1, len2; + const uint8_t *ptr; + + /* extract the two lengths */ + ptr = previous; + _cbor_value_extract_number(&ptr, it->parser->end, &len1); + ptr = current; + _cbor_value_extract_number(&ptr, it->parser->end, &len2); + + if (len1 > len2) + return CborErrorMapNotSorted; + if (len1 == len2) { + size_t bytelen1 = (size_t)(previous_end - previous); + size_t bytelen2 = (size_t)(it->ptr - current); + int r = memcmp(previous, current, bytelen1 <= bytelen2 ? bytelen1 : bytelen2); + + if (r == 0 && bytelen1 != bytelen2) + r = bytelen1 < bytelen2 ? -1 : +1; + if (r > 0) + return CborErrorMapNotSorted; + if (r == 0 && (flags & CborValidateMapKeysAreUnique) == CborValidateMapKeysAreUnique) + return CborErrorMapKeysNotUnique; + } + } + + previous = current; + previous_end = it->ptr; + } + + /* map: that was the key, so get the value */ + err = validate_value(it, flags, recursionLeft); + if (err) + return err; + } + return CborNoError; +} + +static CborError validate_value(CborValue *it, uint32_t flags, int recursionLeft) +{ + CborError err; + CborType type = cbor_value_get_type(it); + + if (cbor_value_is_length_known(it)) { + err = validate_number(it, type, flags); + if (err) + return err; + } else { + if (flags & CborValidateNoIndeterminateLength) + return CborErrorUnknownLength; + } + + switch (type) { + case CborArrayType: + case CborMapType: { + /* recursive type */ + CborValue recursed; + err = cbor_value_enter_container(it, &recursed); + if (!err) + err = validate_container(&recursed, type, flags, recursionLeft - 1); + if (err) { + it->ptr = recursed.ptr; + return err; + } + err = cbor_value_leave_container(it, &recursed); + if (err) + return err; + return CborNoError; + } + + case CborIntegerType: { + uint64_t val; + err = cbor_value_get_raw_integer(it, &val); + cbor_assert(err == CborNoError); /* can't fail */ + + break; + } + + case CborByteStringType: + case CborTextStringType: { + size_t n = 0; + const void *ptr; + + err = _cbor_value_prepare_string_iteration(it); + if (err) + return err; + + while (1) { + err = validate_number(it, type, flags); + if (err) + return err; + + err = _cbor_value_get_string_chunk(it, &ptr, &n, it); + if (err) + return err; + if (!ptr) + break; + + if (type == CborTextStringType && flags & CborValidateUtf8) { + err = validate_utf8_string(ptr, n); + if (err) + return err; + } + } + + return CborNoError; + } + + case CborTagType: { + CborTag tag; + err = cbor_value_get_tag(it, &tag); + cbor_assert(err == CborNoError); /* can't fail */ + + err = cbor_value_advance_fixed(it); + if (err) + return err; + err = validate_tag(it, tag, flags, recursionLeft - 1); + if (err) + return err; + + return CborNoError; + } + + case CborSimpleType: { + uint8_t simple_type; + err = cbor_value_get_simple_type(it, &simple_type); + cbor_assert(err == CborNoError); /* can't fail */ + err = validate_simple_type(simple_type, flags); + if (err) + return err; + break; + } + + case CborNullType: + case CborBooleanType: + break; + + case CborUndefinedType: + if (flags & CborValidateNoUndefined) + return CborErrorExcludedType; + break; + + case CborHalfFloatType: + case CborFloatType: + case CborDoubleType: { +#ifdef CBOR_NO_FLOATING_POINT + return CborErrorUnsupportedType; +#else + err = validate_floating_point(it, type, flags); + if (err) + return err; + break; +#endif /* !CBOR_NO_FLOATING_POINT */ + } + + case CborInvalidType: + return CborErrorUnknownType; + } + + err = cbor_value_advance_fixed(it); + return err; +} + +/** + * Performs a full validation, controlled by the \a flags options, of the CBOR + * stream pointed by \a it and returns the error it found. If no error was + * found, it returns CborNoError and the application can iterate over the items + * with certainty that no errors will appear during parsing. + * + * If \a flags is CborValidateBasic, the result should be the same as + * cbor_value_validate_basic(). + * + * This function has the same timing and memory requirements as + * cbor_value_advance() and cbor_value_validate_basic(). + * + * \sa CborValidationFlags, cbor_value_validate_basic(), cbor_value_advance() + */ +CborError cbor_value_validate(const CborValue *it, uint32_t flags) +{ + CborValue value = *it; + CborError err = validate_value(&value, flags, CBOR_PARSER_MAX_RECURSIONS); + if (err) + return err; + if (flags & CborValidateCompleteData && it->ptr != it->parser->end) + return CborErrorGarbageAtEnd; + return CborNoError; +} + +/** + * @} + */