From c75ac31ec97c9a6116403355bc61e3976fe44074 Mon Sep 17 00:00:00 2001 From: David Zeuthen Date: Mon, 28 Oct 2019 13:16:45 -0400 Subject: Add Identity Credential HAL, default implementation, and VTS tests. IIdentityCredentialStore provides an interface to a secure store for user identity documents. This HAL is deliberately fairly general and abstract. To the extent possible, specification of the message formats and semantics of communication with credential verification devices and issuing authorities (IAs) is out of scope for this HAL. It provides the interface with secure storage but a credential-specific Android application will be required to implement the presentation and verification protocols and processes appropriate for the specific credential type. Bug: 111446262 Test: VtsHalIdentityCredentialTargetTest Test: android.hardware.identity-support-lib-test Test: CtsIdentityTestCases Change-Id: I64eb50114d645dd475012ad1b889d2177aaf1d37 --- identity/support/include/cppbor/cppbor.h | 827 +++++++++++++++++++++++++++++++ 1 file changed, 827 insertions(+) create mode 100644 identity/support/include/cppbor/cppbor.h (limited to 'identity/support/include/cppbor/cppbor.h') diff --git a/identity/support/include/cppbor/cppbor.h b/identity/support/include/cppbor/cppbor.h new file mode 100644 index 0000000000..a755db13a2 --- /dev/null +++ b/identity/support/include/cppbor/cppbor.h @@ -0,0 +1,827 @@ +/* + * Copyright (c) 2019, The Android Open Source Project + * + * 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. + */ + +#pragma once + +#include +#include +#include +#include +#include +#include +#include + +namespace cppbor { + +enum MajorType : uint8_t { + UINT = 0 << 5, + NINT = 1 << 5, + BSTR = 2 << 5, + TSTR = 3 << 5, + ARRAY = 4 << 5, + MAP = 5 << 5, + SEMANTIC = 6 << 5, + SIMPLE = 7 << 5, +}; + +enum SimpleType { + BOOLEAN, + NULL_T, // Only two supported, as yet. +}; + +enum SpecialAddlInfoValues : uint8_t { + FALSE = 20, + TRUE = 21, + NULL_V = 22, + ONE_BYTE_LENGTH = 24, + TWO_BYTE_LENGTH = 25, + FOUR_BYTE_LENGTH = 26, + EIGHT_BYTE_LENGTH = 27, +}; + +class Item; +class Uint; +class Nint; +class Int; +class Tstr; +class Bstr; +class Simple; +class Bool; +class Array; +class Map; +class Null; +class Semantic; + +/** + * Returns the size of a CBOR header that contains the additional info value addlInfo. + */ +size_t headerSize(uint64_t addlInfo); + +/** + * Encodes a CBOR header with the specified type and additional info into the range [pos, end). + * Returns a pointer to one past the last byte written, or nullptr if there isn't sufficient space + * to write the header. + */ +uint8_t* encodeHeader(MajorType type, uint64_t addlInfo, uint8_t* pos, const uint8_t* end); + +using EncodeCallback = std::function; + +/** + * Encodes a CBOR header with the specified type and additional info, passing each byte in turn to + * encodeCallback. + */ +void encodeHeader(MajorType type, uint64_t addlInfo, EncodeCallback encodeCallback); + +/** + * Encodes a CBOR header with the specified type and additional info, writing each byte to the + * provided OutputIterator. + */ +template ::iterator_category>>> +void encodeHeader(MajorType type, uint64_t addlInfo, OutputIterator iter) { + return encodeHeader(type, addlInfo, [&](uint8_t v) { *iter++ = v; }); +} + +/** + * Item represents a CBOR-encodeable data item. Item is an abstract interface with a set of virtual + * methods that allow encoding of the item or conversion to the appropriate derived type. + */ +class Item { + public: + virtual ~Item() {} + + /** + * Returns the CBOR type of the item. + */ + virtual MajorType type() const = 0; + + // These methods safely downcast an Item to the appropriate subclass. + virtual const Int* asInt() const { return nullptr; } + virtual const Uint* asUint() const { return nullptr; } + virtual const Nint* asNint() const { return nullptr; } + virtual const Tstr* asTstr() const { return nullptr; } + virtual const Bstr* asBstr() const { return nullptr; } + virtual const Simple* asSimple() const { return nullptr; } + virtual const Map* asMap() const { return nullptr; } + virtual const Array* asArray() const { return nullptr; } + virtual const Semantic* asSemantic() const { return nullptr; } + + /** + * Returns true if this is a "compound" item, i.e. one that contains one or more other items. + */ + virtual bool isCompound() const { return false; } + + bool operator==(const Item& other) const&; + bool operator!=(const Item& other) const& { return !(*this == other); } + + /** + * Returns the number of bytes required to encode this Item into CBOR. Note that if this is a + * complex Item, calling this method will require walking the whole tree. + */ + virtual size_t encodedSize() const = 0; + + /** + * Encodes the Item into buffer referenced by range [*pos, end). Returns a pointer to one past + * the last position written. Returns nullptr if there isn't enough space to encode. + */ + virtual uint8_t* encode(uint8_t* pos, const uint8_t* end) const = 0; + + /** + * Encodes the Item by passing each encoded byte to encodeCallback. + */ + virtual void encode(EncodeCallback encodeCallback) const = 0; + + /** + * Clones the Item + */ + virtual std::unique_ptr clone() const = 0; + + /** + * Encodes the Item into the provided OutputIterator. + */ + template ::iterator_category> + void encode(OutputIterator i) const { + return encode([&](uint8_t v) { *i++ = v; }); + } + + /** + * Encodes the Item into a new std::vector. + */ + std::vector encode() const { + std::vector retval; + retval.reserve(encodedSize()); + encode(std::back_inserter(retval)); + return retval; + } + + /** + * Encodes the Item into a new std::string. + */ + std::string toString() const { + std::string retval; + retval.reserve(encodedSize()); + encode([&](uint8_t v) { retval.push_back(v); }); + return retval; + } + + /** + * Encodes only the header of the Item. + */ + inline uint8_t* encodeHeader(uint64_t addlInfo, uint8_t* pos, const uint8_t* end) const { + return ::cppbor::encodeHeader(type(), addlInfo, pos, end); + } + + /** + * Encodes only the header of the Item. + */ + inline void encodeHeader(uint64_t addlInfo, EncodeCallback encodeCallback) const { + ::cppbor::encodeHeader(type(), addlInfo, encodeCallback); + } +}; + +/** + * Int is an abstraction that allows Uint and Nint objects to be manipulated without caring about + * the sign. + */ +class Int : public Item { + public: + bool operator==(const Int& other) const& { return value() == other.value(); } + + virtual int64_t value() const = 0; + + const Int* asInt() const override { return this; } +}; + +/** + * Uint is a concrete Item that implements CBOR major type 0. + */ +class Uint : public Int { + public: + static constexpr MajorType kMajorType = UINT; + + explicit Uint(uint64_t v) : mValue(v) {} + + bool operator==(const Uint& other) const& { return mValue == other.mValue; } + + MajorType type() const override { return kMajorType; } + const Uint* asUint() const override { return this; } + + size_t encodedSize() const override { return headerSize(mValue); } + + int64_t value() const override { return mValue; } + uint64_t unsignedValue() const { return mValue; } + + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override { + return encodeHeader(mValue, pos, end); + } + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(mValue, encodeCallback); + } + + virtual std::unique_ptr clone() const override { return std::make_unique(mValue); } + + private: + uint64_t mValue; +}; + +/** + * Nint is a concrete Item that implements CBOR major type 1. + + * Note that it is incapable of expressing the full range of major type 1 values, becaue it can only + * express values that fall into the range [std::numeric_limits::min(), -1]. It cannot + * express values in the range [std::numeric_limits::min() - 1, + * -std::numeric_limits::max()]. + */ +class Nint : public Int { + public: + static constexpr MajorType kMajorType = NINT; + + explicit Nint(int64_t v); + + bool operator==(const Nint& other) const& { return mValue == other.mValue; } + + MajorType type() const override { return kMajorType; } + const Nint* asNint() const override { return this; } + size_t encodedSize() const override { return headerSize(addlInfo()); } + + int64_t value() const override { return mValue; } + + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override { + return encodeHeader(addlInfo(), pos, end); + } + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(addlInfo(), encodeCallback); + } + + virtual std::unique_ptr clone() const override { return std::make_unique(mValue); } + + private: + uint64_t addlInfo() const { return -1ll - mValue; } + + int64_t mValue; +}; + +/** + * Bstr is a concrete Item that implements major type 2. + */ +class Bstr : public Item { + public: + static constexpr MajorType kMajorType = BSTR; + + // Construct from a vector + explicit Bstr(std::vector v) : mValue(std::move(v)) {} + + // Construct from a string + explicit Bstr(const std::string& v) + : mValue(reinterpret_cast(v.data()), + reinterpret_cast(v.data()) + v.size()) {} + + // Construct from a pointer/size pair + explicit Bstr(const std::pair& buf) + : mValue(buf.first, buf.first + buf.second) {} + + // Construct from a pair of iterators + template ::iterator_category, + typename = typename std::iterator_traits::iterator_category> + explicit Bstr(const std::pair& pair) : mValue(pair.first, pair.second) {} + + // Construct from an iterator range. + template ::iterator_category, + typename = typename std::iterator_traits::iterator_category> + Bstr(I1 begin, I2 end) : mValue(begin, end) {} + + bool operator==(const Bstr& other) const& { return mValue == other.mValue; } + + MajorType type() const override { return kMajorType; } + const Bstr* asBstr() const override { return this; } + size_t encodedSize() const override { return headerSize(mValue.size()) + mValue.size(); } + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override; + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(mValue.size(), encodeCallback); + encodeValue(encodeCallback); + } + + const std::vector& value() const { return mValue; } + + virtual std::unique_ptr clone() const override { return std::make_unique(mValue); } + + private: + void encodeValue(EncodeCallback encodeCallback) const; + + std::vector mValue; +}; + +/** + * Bstr is a concrete Item that implements major type 3. + */ +class Tstr : public Item { + public: + static constexpr MajorType kMajorType = TSTR; + + // Construct from a string + explicit Tstr(std::string v) : mValue(std::move(v)) {} + + // Construct from a string_view + explicit Tstr(const std::string_view& v) : mValue(v) {} + + // Construct from a C string + explicit Tstr(const char* v) : mValue(std::string(v)) {} + + // Construct from a pair of iterators + template ::iterator_category, + typename = typename std::iterator_traits::iterator_category> + explicit Tstr(const std::pair& pair) : mValue(pair.first, pair.second) {} + + // Construct from an iterator range + template ::iterator_category, + typename = typename std::iterator_traits::iterator_category> + Tstr(I1 begin, I2 end) : mValue(begin, end) {} + + bool operator==(const Tstr& other) const& { return mValue == other.mValue; } + + MajorType type() const override { return kMajorType; } + const Tstr* asTstr() const override { return this; } + size_t encodedSize() const override { return headerSize(mValue.size()) + mValue.size(); } + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override; + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(mValue.size(), encodeCallback); + encodeValue(encodeCallback); + } + + const std::string& value() const { return mValue; } + + virtual std::unique_ptr clone() const override { return std::make_unique(mValue); } + + private: + void encodeValue(EncodeCallback encodeCallback) const; + + std::string mValue; +}; + +/** + * CompoundItem is an abstract Item that provides common functionality for Items that contain other + * items, i.e. Arrays (CBOR type 4) and Maps (CBOR type 5). + */ +class CompoundItem : public Item { + public: + bool operator==(const CompoundItem& other) const&; + + virtual size_t size() const { return mEntries.size(); } + + bool isCompound() const override { return true; } + + size_t encodedSize() const override { + return std::accumulate(mEntries.begin(), mEntries.end(), headerSize(size()), + [](size_t sum, auto& entry) { return sum + entry->encodedSize(); }); + } + + using Item::encode; // Make base versions visible. + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override; + void encode(EncodeCallback encodeCallback) const override; + + virtual uint64_t addlInfo() const = 0; + + protected: + std::vector> mEntries; +}; + +/* + * Array is a concrete Item that implements CBOR major type 4. + * + * Note that Arrays are not copyable. This is because copying them is expensive and making them + * move-only ensures that they're never copied accidentally. If you actually want to copy an Array, + * use the clone() method. + */ +class Array : public CompoundItem { + public: + static constexpr MajorType kMajorType = ARRAY; + + Array() = default; + Array(const Array& other) = delete; + Array(Array&&) = default; + Array& operator=(const Array&) = delete; + Array& operator=(Array&&) = default; + + /** + * Construct an Array from a variable number of arguments of different types. See + * details::makeItem below for details on what types may be provided. In general, this accepts + * all of the types you'd expect and doest the things you'd expect (integral values are addes as + * Uint or Nint, std::string and char* are added as Tstr, bools are added as Bool, etc.). + */ + template + Array(Args&&... args); + + /** + * Append a single element to the Array, of any compatible type. + */ + template + Array& add(T&& v) &; + template + Array&& add(T&& v) &&; + + const std::unique_ptr& operator[](size_t index) const { return mEntries[index]; } + std::unique_ptr& operator[](size_t index) { return mEntries[index]; } + + MajorType type() const override { return kMajorType; } + const Array* asArray() const override { return this; } + + virtual std::unique_ptr clone() const override; + + uint64_t addlInfo() const override { return size(); } +}; + +/* + * Map is a concrete Item that implements CBOR major type 5. + * + * Note that Maps are not copyable. This is because copying them is expensive and making them + * move-only ensures that they're never copied accidentally. If you actually want to copy a + * Map, use the clone() method. + */ +class Map : public CompoundItem { + public: + static constexpr MajorType kMajorType = MAP; + + Map() = default; + Map(const Map& other) = delete; + Map(Map&&) = default; + Map& operator=(const Map& other) = delete; + Map& operator=(Map&&) = default; + + /** + * Construct a Map from a variable number of arguments of different types. An even number of + * arguments must be provided (this is verified statically). See details::makeItem below for + * details on what types may be provided. In general, this accepts all of the types you'd + * expect and doest the things you'd expect (integral values are addes as Uint or Nint, + * std::string and char* are added as Tstr, bools are added as Bool, etc.). + */ + template + Map(Args&&... args); + + /** + * Append a key/value pair to the Map, of any compatible types. + */ + template + Map& add(Key&& key, Value&& value) &; + template + Map&& add(Key&& key, Value&& value) &&; + + size_t size() const override { + assertInvariant(); + return mEntries.size() / 2; + } + + template + std::pair&, bool> get(Key key); + + std::pair&, const std::unique_ptr&> operator[]( + size_t index) const { + assertInvariant(); + return {mEntries[index * 2], mEntries[index * 2 + 1]}; + } + + std::pair&, std::unique_ptr&> operator[](size_t index) { + assertInvariant(); + return {mEntries[index * 2], mEntries[index * 2 + 1]}; + } + + MajorType type() const override { return kMajorType; } + const Map* asMap() const override { return this; } + + virtual std::unique_ptr clone() const override; + + uint64_t addlInfo() const override { return size(); } + + private: + void assertInvariant() const; +}; + +class Semantic : public CompoundItem { + public: + static constexpr MajorType kMajorType = SEMANTIC; + + template + explicit Semantic(uint64_t value, T&& child); + + Semantic(const Semantic& other) = delete; + Semantic(Semantic&&) = default; + Semantic& operator=(const Semantic& other) = delete; + Semantic& operator=(Semantic&&) = default; + + size_t size() const override { + assertInvariant(); + return 1; + } + + size_t encodedSize() const override { + return std::accumulate(mEntries.begin(), mEntries.end(), headerSize(mValue), + [](size_t sum, auto& entry) { return sum + entry->encodedSize(); }); + } + + MajorType type() const override { return kMajorType; } + const Semantic* asSemantic() const override { return this; } + + const std::unique_ptr& child() const { + assertInvariant(); + return mEntries[0]; + } + + std::unique_ptr& child() { + assertInvariant(); + return mEntries[0]; + } + + uint64_t value() const { return mValue; } + + uint64_t addlInfo() const override { return value(); } + + virtual std::unique_ptr clone() const override { + assertInvariant(); + return std::make_unique(mValue, mEntries[0]->clone()); + } + + protected: + Semantic() = default; + Semantic(uint64_t value) : mValue(value) {} + uint64_t mValue; + + private: + void assertInvariant() const; +}; + +/** + * Simple is abstract Item that implements CBOR major type 7. It is intended to be subclassed to + * create concrete Simple types. At present only Bool is provided. + */ +class Simple : public Item { + public: + static constexpr MajorType kMajorType = SIMPLE; + + bool operator==(const Simple& other) const&; + + virtual SimpleType simpleType() const = 0; + MajorType type() const override { return kMajorType; } + + const Simple* asSimple() const override { return this; } + + virtual const Bool* asBool() const { return nullptr; }; + virtual const Null* asNull() const { return nullptr; }; +}; + +/** + * Bool is a concrete type that implements CBOR major type 7, with additional item values for TRUE + * and FALSE. + */ +class Bool : public Simple { + public: + static constexpr SimpleType kSimpleType = BOOLEAN; + + explicit Bool(bool v) : mValue(v) {} + + bool operator==(const Bool& other) const& { return mValue == other.mValue; } + + SimpleType simpleType() const override { return kSimpleType; } + const Bool* asBool() const override { return this; } + + size_t encodedSize() const override { return 1; } + + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override { + return encodeHeader(mValue ? TRUE : FALSE, pos, end); + } + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(mValue ? TRUE : FALSE, encodeCallback); + } + + bool value() const { return mValue; } + + virtual std::unique_ptr clone() const override { return std::make_unique(mValue); } + + private: + bool mValue; +}; + +/** + * Null is a concrete type that implements CBOR major type 7, with additional item value for NULL + */ +class Null : public Simple { + public: + static constexpr SimpleType kSimpleType = NULL_T; + + explicit Null() {} + + SimpleType simpleType() const override { return kSimpleType; } + const Null* asNull() const override { return this; } + + size_t encodedSize() const override { return 1; } + + using Item::encode; + uint8_t* encode(uint8_t* pos, const uint8_t* end) const override { + return encodeHeader(NULL_V, pos, end); + } + void encode(EncodeCallback encodeCallback) const override { + encodeHeader(NULL_V, encodeCallback); + } + + virtual std::unique_ptr clone() const override { return std::make_unique(); } +}; + +template +std::unique_ptr downcastItem(std::unique_ptr&& v) { + static_assert(std::is_base_of_v && !std::is_abstract_v, + "returned type is not an Item or is an abstract class"); + if (v && T::kMajorType == v->type()) { + if constexpr (std::is_base_of_v) { + if (T::kSimpleType != v->asSimple()->simpleType()) { + return nullptr; + } + } + return std::unique_ptr(static_cast(v.release())); + } else { + return nullptr; + } +} + +/** + * Details. Mostly you shouldn't have to look below, except perhaps at the docstring for makeItem. + */ +namespace details { + +template +struct is_iterator_pair_over : public std::false_type {}; + +template +struct is_iterator_pair_over< + std::pair, V, + typename std::enable_if_t::value_type>>> + : public std::true_type {}; + +template +struct is_unique_ptr_of_subclass_of_v : public std::false_type {}; + +template +struct is_unique_ptr_of_subclass_of_v, + typename std::enable_if_t>> + : public std::true_type {}; + +/* check if type is one of std::string (1), std::string_view (2), null-terminated char* (3) or pair + * of iterators (4)*/ +template +struct is_text_type_v : public std::false_type {}; + +template +struct is_text_type_v< + T, typename std::enable_if_t< + /* case 1 */ // + std::is_same_v>, std::string> + /* case 2 */ // + || std::is_same_v>, std::string_view> + /* case 3 */ // + || std::is_same_v>, char*> // + || std::is_same_v>, const char*> + /* case 4 */ + || details::is_iterator_pair_over::value>> : public std::true_type {}; + +/** + * Construct a unique_ptr from many argument types. Accepts: + * + * (a) booleans; + * (b) integers, all sizes and signs; + * (c) text strings, as defined by is_text_type_v above; + * (d) byte strings, as std::vector(d1), pair of iterators (d2) or pair + * (d3); and + * (e) Item subclass instances, including Array and Map. Items may be provided by naked pointer + * (e1), unique_ptr (e2), reference (e3) or value (e3). If provided by reference or value, will + * be moved if possible. If provided by pointer, ownership is taken. + * (f) null pointer; + */ +template +std::unique_ptr makeItem(T v) { + Item* p = nullptr; + if constexpr (/* case a */ std::is_same_v) { + p = new Bool(v); + } else if constexpr (/* case b */ std::is_integral_v) { // b + if (v < 0) { + p = new Nint(v); + } else { + p = new Uint(static_cast(v)); + } + } else if constexpr (/* case c */ // + details::is_text_type_v::value) { + p = new Tstr(v); + } else if constexpr (/* case d1 */ // + std::is_same_v>, + std::vector> + /* case d2 */ // + || details::is_iterator_pair_over::value + /* case d3 */ // + || std::is_same_v>, + std::pair>) { + p = new Bstr(v); + } else if constexpr (/* case e1 */ // + std::is_pointer_v && + std::is_base_of_v>) { + p = v; + } else if constexpr (/* case e2 */ // + details::is_unique_ptr_of_subclass_of_v::value) { + p = v.release(); + } else if constexpr (/* case e3 */ // + std::is_base_of_v) { + p = new T(std::move(v)); + } else if constexpr (/* case f */ std::is_null_pointer_v) { + p = new Null(); + } else { + // It's odd that this can't be static_assert(false), since it shouldn't be evaluated if one + // of the above ifs matches. But static_assert(false) always triggers. + static_assert(std::is_same_v, "makeItem called with unsupported type"); + } + return std::unique_ptr(p); +} + +} // namespace details + +template >> || ...)>> +Array::Array(Args&&... args) { + mEntries.reserve(sizeof...(args)); + (mEntries.push_back(details::makeItem(std::forward(args))), ...); +} + +template +Array& Array::add(T&& v) & { + mEntries.push_back(details::makeItem(std::forward(v))); + return *this; +} + +template +Array&& Array::add(T&& v) && { + mEntries.push_back(details::makeItem(std::forward(v))); + return std::move(*this); +} + +template > +Map::Map(Args&&... args) { + static_assert((sizeof...(Args)) % 2 == 0, "Map must have an even number of entries"); + mEntries.reserve(sizeof...(args)); + (mEntries.push_back(details::makeItem(std::forward(args))), ...); +} + +template +Map& Map::add(Key&& key, Value&& value) & { + mEntries.push_back(details::makeItem(std::forward(key))); + mEntries.push_back(details::makeItem(std::forward(value))); + return *this; +} + +template +Map&& Map::add(Key&& key, Value&& value) && { + this->add(std::forward(key), std::forward(value)); + return std::move(*this); +} + +template || + details::is_text_type_v::value>> +std::pair&, bool> Map::get(Key key) { + assertInvariant(); + auto keyItem = details::makeItem(key); + for (size_t i = 0; i < mEntries.size(); i += 2) { + if (*keyItem == *mEntries[i]) { + return {mEntries[i + 1], true}; + } + } + return {keyItem, false}; +} + +template +Semantic::Semantic(uint64_t value, T&& child) : mValue(value) { + mEntries.reserve(1); + mEntries.push_back(details::makeItem(std::forward(child))); +} + +} // namespace cppbor -- cgit v1.2.3