xref: /aosp_15_r20/system/keymaster/include/keymaster/serializable.h (revision 789431f29546679ab5188a97751fb38e3018d44d)
1*789431f2SAndroid Build Coastguard Worker /*
2*789431f2SAndroid Build Coastguard Worker  * Copyright 2014 The Android Open Source Project
3*789431f2SAndroid Build Coastguard Worker  *
4*789431f2SAndroid Build Coastguard Worker  * Licensed under the Apache License, Version 2.0 (the "License");
5*789431f2SAndroid Build Coastguard Worker  * you may not use this file except in compliance with the License.
6*789431f2SAndroid Build Coastguard Worker  * You may obtain a copy of the License at
7*789431f2SAndroid Build Coastguard Worker  *
8*789431f2SAndroid Build Coastguard Worker  *      http://www.apache.org/licenses/LICENSE-2.0
9*789431f2SAndroid Build Coastguard Worker  *
10*789431f2SAndroid Build Coastguard Worker  * Unless required by applicable law or agreed to in writing, software
11*789431f2SAndroid Build Coastguard Worker  * distributed under the License is distributed on an "AS IS" BASIS,
12*789431f2SAndroid Build Coastguard Worker  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13*789431f2SAndroid Build Coastguard Worker  * See the License for the specific language governing permissions and
14*789431f2SAndroid Build Coastguard Worker  * limitations under the License.
15*789431f2SAndroid Build Coastguard Worker  */
16*789431f2SAndroid Build Coastguard Worker 
17*789431f2SAndroid Build Coastguard Worker #pragma once
18*789431f2SAndroid Build Coastguard Worker 
19*789431f2SAndroid Build Coastguard Worker #include <stddef.h>
20*789431f2SAndroid Build Coastguard Worker #include <stdint.h>
21*789431f2SAndroid Build Coastguard Worker #include <stdlib.h>
22*789431f2SAndroid Build Coastguard Worker #include <string.h>
23*789431f2SAndroid Build Coastguard Worker 
24*789431f2SAndroid Build Coastguard Worker #include <iterator>
25*789431f2SAndroid Build Coastguard Worker #include <utility>
26*789431f2SAndroid Build Coastguard Worker 
27*789431f2SAndroid Build Coastguard Worker #include <keymaster/UniquePtr.h>
28*789431f2SAndroid Build Coastguard Worker #include <keymaster/logger.h>
29*789431f2SAndroid Build Coastguard Worker #include <keymaster/mem.h>
30*789431f2SAndroid Build Coastguard Worker 
31*789431f2SAndroid Build Coastguard Worker namespace keymaster {
32*789431f2SAndroid Build Coastguard Worker 
33*789431f2SAndroid Build Coastguard Worker class Serializable {
34*789431f2SAndroid Build Coastguard Worker   public:
Serializable()35*789431f2SAndroid Build Coastguard Worker     Serializable() {}
~Serializable()36*789431f2SAndroid Build Coastguard Worker     virtual ~Serializable() {}
37*789431f2SAndroid Build Coastguard Worker 
38*789431f2SAndroid Build Coastguard Worker     /**
39*789431f2SAndroid Build Coastguard Worker      * Return the size of the serialized representation of this object.
40*789431f2SAndroid Build Coastguard Worker      */
41*789431f2SAndroid Build Coastguard Worker     virtual size_t SerializedSize() const = 0;
42*789431f2SAndroid Build Coastguard Worker 
43*789431f2SAndroid Build Coastguard Worker     /**
44*789431f2SAndroid Build Coastguard Worker      * Serialize this object into the provided buffer.  Returns a pointer to the byte after the last
45*789431f2SAndroid Build Coastguard Worker      * written.  Will not write past \p end, which should point to \p buf + size of the buffer
46*789431f2SAndroid Build Coastguard Worker      * (i.e. one past the end of the buffer).
47*789431f2SAndroid Build Coastguard Worker      */
48*789431f2SAndroid Build Coastguard Worker     virtual uint8_t* Serialize(uint8_t* buf, const uint8_t* end) const = 0;
49*789431f2SAndroid Build Coastguard Worker 
50*789431f2SAndroid Build Coastguard Worker     /**
51*789431f2SAndroid Build Coastguard Worker      * Deserialize from the provided buffer, copying the data into newly-allocated storage.  Returns
52*789431f2SAndroid Build Coastguard Worker      * true if successful, and advances *buf past the bytes read.
53*789431f2SAndroid Build Coastguard Worker      */
54*789431f2SAndroid Build Coastguard Worker     virtual bool Deserialize(const uint8_t** buf_ptr, const uint8_t* end) = 0;
55*789431f2SAndroid Build Coastguard Worker 
56*789431f2SAndroid Build Coastguard Worker     // Disallow copying and assignment.
57*789431f2SAndroid Build Coastguard Worker     Serializable(const Serializable&) = delete;
58*789431f2SAndroid Build Coastguard Worker     Serializable& operator=(const Serializable&) = delete;
59*789431f2SAndroid Build Coastguard Worker 
60*789431f2SAndroid Build Coastguard Worker     // Move only.
61*789431f2SAndroid Build Coastguard Worker     Serializable(Serializable&&) = default;
62*789431f2SAndroid Build Coastguard Worker     Serializable& operator=(Serializable&&) = default;
63*789431f2SAndroid Build Coastguard Worker };
64*789431f2SAndroid Build Coastguard Worker 
65*789431f2SAndroid Build Coastguard Worker /*
66*789431f2SAndroid Build Coastguard Worker  * Utility functions for writing Serialize() methods
67*789431f2SAndroid Build Coastguard Worker  */
68*789431f2SAndroid Build Coastguard Worker 
69*789431f2SAndroid Build Coastguard Worker /**
70*789431f2SAndroid Build Coastguard Worker  * Convert a pointer into a value.  This is used to make sure compiler won't optimize away pointer
71*789431f2SAndroid Build Coastguard Worker  * overflow checks. (See http://www.kb.cert.org/vuls/id/162289)
72*789431f2SAndroid Build Coastguard Worker  */
__pval(const T * p)73*789431f2SAndroid Build Coastguard Worker template <typename T> inline uintptr_t __pval(const T* p) {
74*789431f2SAndroid Build Coastguard Worker     return reinterpret_cast<uintptr_t>(p);
75*789431f2SAndroid Build Coastguard Worker }
76*789431f2SAndroid Build Coastguard Worker 
77*789431f2SAndroid Build Coastguard Worker /**
78*789431f2SAndroid Build Coastguard Worker  * Performs an overflow-checked bounds check. Returns true iff \p buf + \p len is less than
79*789431f2SAndroid Build Coastguard Worker  * \p end.
80*789431f2SAndroid Build Coastguard Worker  */
81*789431f2SAndroid Build Coastguard Worker bool __buffer_bound_check(const uint8_t* buf, const uint8_t* end, size_t len);
82*789431f2SAndroid Build Coastguard Worker 
83*789431f2SAndroid Build Coastguard Worker /**
84*789431f2SAndroid Build Coastguard Worker  * Append a byte array to a buffer.  Note that by itself this function isn't very useful, because it
85*789431f2SAndroid Build Coastguard Worker  * provides no indication in the serialized buffer of what the array size is.  For writing arrays,
86*789431f2SAndroid Build Coastguard Worker  * see \p append_size_and_data_to_buf().
87*789431f2SAndroid Build Coastguard Worker  *
88*789431f2SAndroid Build Coastguard Worker  * Returns a pointer to the first byte after the data written.
89*789431f2SAndroid Build Coastguard Worker  */
90*789431f2SAndroid Build Coastguard Worker uint8_t* append_to_buf(uint8_t* buf, const uint8_t* end, const void* data, size_t data_len);
91*789431f2SAndroid Build Coastguard Worker 
92*789431f2SAndroid Build Coastguard Worker /**
93*789431f2SAndroid Build Coastguard Worker  * Append some type of value convertible to a uint32_t to a buffer.  This is primarily used for
94*789431f2SAndroid Build Coastguard Worker  * writing enumerated values, and uint32_ts.
95*789431f2SAndroid Build Coastguard Worker  *
96*789431f2SAndroid Build Coastguard Worker  * Returns a pointer to the first byte after the data written.
97*789431f2SAndroid Build Coastguard Worker  */
98*789431f2SAndroid Build Coastguard Worker template <typename T>
append_uint32_to_buf(uint8_t * buf,const uint8_t * end,T value)99*789431f2SAndroid Build Coastguard Worker inline uint8_t* append_uint32_to_buf(uint8_t* buf, const uint8_t* end, T value) {
100*789431f2SAndroid Build Coastguard Worker     uint32_t val = static_cast<uint32_t>(value);
101*789431f2SAndroid Build Coastguard Worker     return append_to_buf(buf, end, &val, sizeof(val));
102*789431f2SAndroid Build Coastguard Worker }
103*789431f2SAndroid Build Coastguard Worker 
104*789431f2SAndroid Build Coastguard Worker /**
105*789431f2SAndroid Build Coastguard Worker  * Append a uint64_t to a buffer.  Returns a pointer to the first byte after the data written.
106*789431f2SAndroid Build Coastguard Worker  */
append_uint64_to_buf(uint8_t * buf,const uint8_t * end,uint64_t value)107*789431f2SAndroid Build Coastguard Worker inline uint8_t* append_uint64_to_buf(uint8_t* buf, const uint8_t* end, uint64_t value) {
108*789431f2SAndroid Build Coastguard Worker     return append_to_buf(buf, end, &value, sizeof(value));
109*789431f2SAndroid Build Coastguard Worker }
110*789431f2SAndroid Build Coastguard Worker 
111*789431f2SAndroid Build Coastguard Worker /**
112*789431f2SAndroid Build Coastguard Worker  * Appends a byte array to a buffer, prefixing it with a 32-bit size field.  Returns a pointer to
113*789431f2SAndroid Build Coastguard Worker  * the first byte after the data written.
114*789431f2SAndroid Build Coastguard Worker  *
115*789431f2SAndroid Build Coastguard Worker  * See copy_size_and_data_from_buf().
116*789431f2SAndroid Build Coastguard Worker  */
append_size_and_data_to_buf(uint8_t * buf,const uint8_t * end,const void * data,size_t data_len)117*789431f2SAndroid Build Coastguard Worker inline uint8_t* append_size_and_data_to_buf(uint8_t* buf, const uint8_t* end, const void* data,
118*789431f2SAndroid Build Coastguard Worker                                             size_t data_len) {
119*789431f2SAndroid Build Coastguard Worker     buf = append_uint32_to_buf(buf, end, data_len);
120*789431f2SAndroid Build Coastguard Worker     return append_to_buf(buf, end, data, data_len);
121*789431f2SAndroid Build Coastguard Worker }
122*789431f2SAndroid Build Coastguard Worker 
123*789431f2SAndroid Build Coastguard Worker /**
124*789431f2SAndroid Build Coastguard Worker  * Append a collection type to buffer. The type must implement `size` and `data` accessors
125*789431f2SAndroid Build Coastguard Worker  * that return, respectively, the size of the data and a pointer to the start of the data.
126*789431f2SAndroid Build Coastguard Worker  * Returns a pointer to the first byte after the data written.
127*789431f2SAndroid Build Coastguard Worker  */
128*789431f2SAndroid Build Coastguard Worker template <typename T>
append_collection_to_buf(uint8_t * buf,const uint8_t * end,const T & value)129*789431f2SAndroid Build Coastguard Worker uint8_t* append_collection_to_buf(uint8_t* buf, const uint8_t* end, const T& value) {
130*789431f2SAndroid Build Coastguard Worker     if (value.size() > UINT32_MAX) {
131*789431f2SAndroid Build Coastguard Worker         LOG_E("Skip collection serialization due to integer overflow");
132*789431f2SAndroid Build Coastguard Worker         return buf;
133*789431f2SAndroid Build Coastguard Worker     }
134*789431f2SAndroid Build Coastguard Worker     return append_size_and_data_to_buf(buf, end, value.data(), value.size());
135*789431f2SAndroid Build Coastguard Worker }
136*789431f2SAndroid Build Coastguard Worker 
137*789431f2SAndroid Build Coastguard Worker /**
138*789431f2SAndroid Build Coastguard Worker  * Appends an array of values that are convertible to uint32_t as uint32ts to a buffer, prefixing a
139*789431f2SAndroid Build Coastguard Worker  * count so deserialization knows how many values to read.
140*789431f2SAndroid Build Coastguard Worker  *
141*789431f2SAndroid Build Coastguard Worker  * See copy_uint32_array_from_buf().
142*789431f2SAndroid Build Coastguard Worker  */
143*789431f2SAndroid Build Coastguard Worker template <typename T>
append_uint32_array_to_buf(uint8_t * buf,const uint8_t * end,const T * data,size_t count)144*789431f2SAndroid Build Coastguard Worker inline uint8_t* append_uint32_array_to_buf(uint8_t* buf, const uint8_t* end, const T* data,
145*789431f2SAndroid Build Coastguard Worker                                            size_t count) {
146*789431f2SAndroid Build Coastguard Worker     // Check for overflow
147*789431f2SAndroid Build Coastguard Worker     if (count >= (UINT32_MAX / sizeof(uint32_t)) ||
148*789431f2SAndroid Build Coastguard Worker         __pval(buf) + count * sizeof(uint32_t) < __pval(buf))
149*789431f2SAndroid Build Coastguard Worker         return buf;
150*789431f2SAndroid Build Coastguard Worker     buf = append_uint32_to_buf(buf, end, count);
151*789431f2SAndroid Build Coastguard Worker     for (size_t i = 0; i < count; ++i)
152*789431f2SAndroid Build Coastguard Worker         buf = append_uint32_to_buf(buf, end, static_cast<uint32_t>(data[i]));
153*789431f2SAndroid Build Coastguard Worker     return buf;
154*789431f2SAndroid Build Coastguard Worker }
155*789431f2SAndroid Build Coastguard Worker 
156*789431f2SAndroid Build Coastguard Worker /*
157*789431f2SAndroid Build Coastguard Worker  * Utility functions for writing Deserialize() methods.
158*789431f2SAndroid Build Coastguard Worker  */
159*789431f2SAndroid Build Coastguard Worker 
160*789431f2SAndroid Build Coastguard Worker /**
161*789431f2SAndroid Build Coastguard Worker  * Copy \p size bytes from \p *buf_ptr into \p dest.  If there are fewer than \p size bytes to read,
162*789431f2SAndroid Build Coastguard Worker  * returns false.  Advances *buf_ptr to the next byte to be read.
163*789431f2SAndroid Build Coastguard Worker  */
164*789431f2SAndroid Build Coastguard Worker bool copy_from_buf(const uint8_t** buf_ptr, const uint8_t* end, void* dest, size_t size);
165*789431f2SAndroid Build Coastguard Worker 
166*789431f2SAndroid Build Coastguard Worker /**
167*789431f2SAndroid Build Coastguard Worker  * Extracts a uint32_t size from *buf_ptr, placing it in \p *size, and then reads *size bytes from
168*789431f2SAndroid Build Coastguard Worker  * *buf_ptr, placing them in newly-allocated storage in *dest.  If there aren't enough bytes in
169*789431f2SAndroid Build Coastguard Worker  * *buf_ptr, returns false.  Advances \p *buf_ptr to the next byte to be read.
170*789431f2SAndroid Build Coastguard Worker  *
171*789431f2SAndroid Build Coastguard Worker  * See \p append_size_and_data_to_buf().
172*789431f2SAndroid Build Coastguard Worker  */
173*789431f2SAndroid Build Coastguard Worker bool copy_size_and_data_from_buf(const uint8_t** buf_ptr, const uint8_t* end, size_t* size,
174*789431f2SAndroid Build Coastguard Worker                                  UniquePtr<uint8_t[]>* dest);
175*789431f2SAndroid Build Coastguard Worker 
176*789431f2SAndroid Build Coastguard Worker /**
177*789431f2SAndroid Build Coastguard Worker  * Copies a value convertible from uint32_t from \p *buf_ptr.  Returns false if there are less than
178*789431f2SAndroid Build Coastguard Worker  * four bytes remaining in \p *buf_ptr.  Advances \p *buf_ptr to the next byte to be read.
179*789431f2SAndroid Build Coastguard Worker  */
180*789431f2SAndroid Build Coastguard Worker template <typename T>
copy_uint32_from_buf(const uint8_t ** buf_ptr,const uint8_t * end,T * value)181*789431f2SAndroid Build Coastguard Worker inline bool copy_uint32_from_buf(const uint8_t** buf_ptr, const uint8_t* end, T* value) {
182*789431f2SAndroid Build Coastguard Worker     uint32_t val;
183*789431f2SAndroid Build Coastguard Worker     if (!copy_from_buf(buf_ptr, end, &val, sizeof(val))) return false;
184*789431f2SAndroid Build Coastguard Worker     *value = static_cast<T>(val);
185*789431f2SAndroid Build Coastguard Worker     return true;
186*789431f2SAndroid Build Coastguard Worker }
187*789431f2SAndroid Build Coastguard Worker 
188*789431f2SAndroid Build Coastguard Worker /**
189*789431f2SAndroid Build Coastguard Worker  * Copies a uint64_t from \p *buf_ptr.  Returns false if there are less than eight bytes remaining
190*789431f2SAndroid Build Coastguard Worker  * in \p *buf_ptr.  Advances \p *buf_ptr to the next byte to be read.
191*789431f2SAndroid Build Coastguard Worker  */
copy_uint64_from_buf(const uint8_t ** buf_ptr,const uint8_t * end,uint64_t * value)192*789431f2SAndroid Build Coastguard Worker inline bool copy_uint64_from_buf(const uint8_t** buf_ptr, const uint8_t* end, uint64_t* value) {
193*789431f2SAndroid Build Coastguard Worker     return copy_from_buf(buf_ptr, end, value, sizeof(*value));
194*789431f2SAndroid Build Coastguard Worker }
195*789431f2SAndroid Build Coastguard Worker 
196*789431f2SAndroid Build Coastguard Worker /**
197*789431f2SAndroid Build Coastguard Worker  * Copies an array of values convertible to uint32_t from \p *buf_ptr, first reading a count of
198*789431f2SAndroid Build Coastguard Worker  * values to read. The count is returned in \p *count and the values returned in newly-allocated
199*789431f2SAndroid Build Coastguard Worker  * storage at *data.  Returns false if there are insufficient bytes at \p *buf_ptr.  Advances \p
200*789431f2SAndroid Build Coastguard Worker  * *buf_ptr to the next byte to be read.
201*789431f2SAndroid Build Coastguard Worker  */
202*789431f2SAndroid Build Coastguard Worker template <typename T>
copy_uint32_array_from_buf(const uint8_t ** buf_ptr,const uint8_t * end,UniquePtr<T[]> * data,size_t * count)203*789431f2SAndroid Build Coastguard Worker inline bool copy_uint32_array_from_buf(const uint8_t** buf_ptr, const uint8_t* end,
204*789431f2SAndroid Build Coastguard Worker                                        UniquePtr<T[]>* data, size_t* count) {
205*789431f2SAndroid Build Coastguard Worker     if (!copy_uint32_from_buf(buf_ptr, end, count)) return false;
206*789431f2SAndroid Build Coastguard Worker 
207*789431f2SAndroid Build Coastguard Worker     uintptr_t array_end = __pval(*buf_ptr) + *count * sizeof(uint32_t);
208*789431f2SAndroid Build Coastguard Worker     if (*count >= UINT32_MAX / sizeof(uint32_t) || array_end < __pval(*buf_ptr) ||
209*789431f2SAndroid Build Coastguard Worker         array_end > __pval(end))
210*789431f2SAndroid Build Coastguard Worker         return false;
211*789431f2SAndroid Build Coastguard Worker 
212*789431f2SAndroid Build Coastguard Worker     data->reset(new (std::nothrow) T[*count]);
213*789431f2SAndroid Build Coastguard Worker     if (!data->get()) return false;
214*789431f2SAndroid Build Coastguard Worker     for (size_t i = 0; i < *count; ++i)
215*789431f2SAndroid Build Coastguard Worker         if (!copy_uint32_from_buf(buf_ptr, end, &(*data)[i])) return false;
216*789431f2SAndroid Build Coastguard Worker     return true;
217*789431f2SAndroid Build Coastguard Worker }
218*789431f2SAndroid Build Coastguard Worker 
219*789431f2SAndroid Build Coastguard Worker /**
220*789431f2SAndroid Build Coastguard Worker  * Copies a contiguously-allocated collection type (e.g. string, vector) from \p *buf_ptr. The
221*789431f2SAndroid Build Coastguard Worker  * type \p T must implement `reserve` and `push_back` functions. Returns false if there are less
222*789431f2SAndroid Build Coastguard Worker  * than 4 bytes remaining in \p *buf_ptr.  Advances \p *buf_ptr to the next byte to be read.
223*789431f2SAndroid Build Coastguard Worker  */
224*789431f2SAndroid Build Coastguard Worker template <typename T>
copy_collection_from_buf(const uint8_t ** buf_ptr,const uint8_t * end,T * value)225*789431f2SAndroid Build Coastguard Worker bool copy_collection_from_buf(const uint8_t** buf_ptr, const uint8_t* end, T* value) {
226*789431f2SAndroid Build Coastguard Worker     uint32_t buf_size;
227*789431f2SAndroid Build Coastguard Worker     if (!copy_uint32_from_buf(buf_ptr, end, &buf_size)) {
228*789431f2SAndroid Build Coastguard Worker         return false;
229*789431f2SAndroid Build Coastguard Worker     }
230*789431f2SAndroid Build Coastguard Worker 
231*789431f2SAndroid Build Coastguard Worker     if (!__buffer_bound_check(*buf_ptr, end, buf_size)) {
232*789431f2SAndroid Build Coastguard Worker         LOG_E("Skip collection deserialization due size mismatch");
233*789431f2SAndroid Build Coastguard Worker         return false;
234*789431f2SAndroid Build Coastguard Worker     }
235*789431f2SAndroid Build Coastguard Worker 
236*789431f2SAndroid Build Coastguard Worker     value->reserve(buf_size);
237*789431f2SAndroid Build Coastguard Worker     auto out = std::back_inserter(*value);
238*789431f2SAndroid Build Coastguard Worker     const uint8_t* const value_end = *buf_ptr + buf_size;
239*789431f2SAndroid Build Coastguard Worker     while (*buf_ptr < value_end) {
240*789431f2SAndroid Build Coastguard Worker         *out = **buf_ptr;
241*789431f2SAndroid Build Coastguard Worker         ++out;
242*789431f2SAndroid Build Coastguard Worker         ++*buf_ptr;
243*789431f2SAndroid Build Coastguard Worker     }
244*789431f2SAndroid Build Coastguard Worker     return true;
245*789431f2SAndroid Build Coastguard Worker }
246*789431f2SAndroid Build Coastguard Worker 
247*789431f2SAndroid Build Coastguard Worker /**
248*789431f2SAndroid Build Coastguard Worker  * A simple buffer that supports reading and writing.  Manages its own memory.
249*789431f2SAndroid Build Coastguard Worker  */
250*789431f2SAndroid Build Coastguard Worker class Buffer : public Serializable {
251*789431f2SAndroid Build Coastguard Worker   public:
Buffer()252*789431f2SAndroid Build Coastguard Worker     Buffer() : buffer_(nullptr), buffer_size_(0), read_position_(0), write_position_(0) {}
Buffer(size_t size)253*789431f2SAndroid Build Coastguard Worker     explicit Buffer(size_t size) : buffer_(nullptr) { Reinitialize(size); }
Buffer(const void * buf,size_t size)254*789431f2SAndroid Build Coastguard Worker     Buffer(const void* buf, size_t size) : buffer_(nullptr) { Reinitialize(buf, size); }
Buffer(Buffer && b)255*789431f2SAndroid Build Coastguard Worker     Buffer(Buffer&& b) { *this = std::move(b); }
256*789431f2SAndroid Build Coastguard Worker     Buffer(const Buffer&) = delete;
257*789431f2SAndroid Build Coastguard Worker 
~Buffer()258*789431f2SAndroid Build Coastguard Worker     ~Buffer() { Clear(); }
259*789431f2SAndroid Build Coastguard Worker 
260*789431f2SAndroid Build Coastguard Worker     Buffer& operator=(Buffer&& other) {
261*789431f2SAndroid Build Coastguard Worker         if (this == &other) return *this;
262*789431f2SAndroid Build Coastguard Worker         buffer_ = std::move(other.buffer_);
263*789431f2SAndroid Build Coastguard Worker         buffer_size_ = other.buffer_size_;
264*789431f2SAndroid Build Coastguard Worker         other.buffer_size_ = 0;
265*789431f2SAndroid Build Coastguard Worker         read_position_ = other.read_position_;
266*789431f2SAndroid Build Coastguard Worker         other.read_position_ = 0;
267*789431f2SAndroid Build Coastguard Worker         write_position_ = other.write_position_;
268*789431f2SAndroid Build Coastguard Worker         other.write_position_ = 0;
269*789431f2SAndroid Build Coastguard Worker         return *this;
270*789431f2SAndroid Build Coastguard Worker     }
271*789431f2SAndroid Build Coastguard Worker 
272*789431f2SAndroid Build Coastguard Worker     void operator=(const Buffer& other) = delete;
273*789431f2SAndroid Build Coastguard Worker 
274*789431f2SAndroid Build Coastguard Worker     // Grow the buffer so that at least \p size bytes can be written.
275*789431f2SAndroid Build Coastguard Worker     bool reserve(size_t size);
276*789431f2SAndroid Build Coastguard Worker 
277*789431f2SAndroid Build Coastguard Worker     bool Reinitialize(size_t size);
278*789431f2SAndroid Build Coastguard Worker     bool Reinitialize(const void* buf, size_t size);
279*789431f2SAndroid Build Coastguard Worker 
280*789431f2SAndroid Build Coastguard Worker     // Reinitialize with a copy of the provided buffer's readable data.
Reinitialize(const Buffer & buffer)281*789431f2SAndroid Build Coastguard Worker     bool Reinitialize(const Buffer& buffer) {
282*789431f2SAndroid Build Coastguard Worker         return Reinitialize(buffer.peek_read(), buffer.available_read());
283*789431f2SAndroid Build Coastguard Worker     }
284*789431f2SAndroid Build Coastguard Worker 
begin()285*789431f2SAndroid Build Coastguard Worker     const uint8_t* begin() const { return peek_read(); }
end()286*789431f2SAndroid Build Coastguard Worker     const uint8_t* end() const { return peek_read() + available_read(); }
287*789431f2SAndroid Build Coastguard Worker 
288*789431f2SAndroid Build Coastguard Worker     void Clear();
289*789431f2SAndroid Build Coastguard Worker 
290*789431f2SAndroid Build Coastguard Worker     size_t available_write() const;
291*789431f2SAndroid Build Coastguard Worker     size_t available_read() const;
buffer_size()292*789431f2SAndroid Build Coastguard Worker     size_t buffer_size() const { return buffer_size_; }
293*789431f2SAndroid Build Coastguard Worker     bool valid_buffer_state() const;
294*789431f2SAndroid Build Coastguard Worker 
295*789431f2SAndroid Build Coastguard Worker     bool write(const uint8_t* src, size_t write_length);
write(const uint8_t (& src)[N])296*789431f2SAndroid Build Coastguard Worker     template <size_t N> bool write(const uint8_t (&src)[N]) { return write(src, N); }
297*789431f2SAndroid Build Coastguard Worker     bool read(uint8_t* dest, size_t read_length);
peek_read()298*789431f2SAndroid Build Coastguard Worker     const uint8_t* peek_read() const { return buffer_.get() + read_position_; }
peek_write()299*789431f2SAndroid Build Coastguard Worker     uint8_t* peek_write() { return buffer_.get() + write_position_; }
300*789431f2SAndroid Build Coastguard Worker     bool advance_write(int distance);
301*789431f2SAndroid Build Coastguard Worker     size_t SerializedSize() const;
302*789431f2SAndroid Build Coastguard Worker     uint8_t* Serialize(uint8_t* buf, const uint8_t* end) const;
303*789431f2SAndroid Build Coastguard Worker     bool Deserialize(const uint8_t** buf_ptr, const uint8_t* end);
304*789431f2SAndroid Build Coastguard Worker 
305*789431f2SAndroid Build Coastguard Worker   private:
306*789431f2SAndroid Build Coastguard Worker     UniquePtr<uint8_t[]> buffer_;
307*789431f2SAndroid Build Coastguard Worker     size_t buffer_size_;
308*789431f2SAndroid Build Coastguard Worker     size_t read_position_;
309*789431f2SAndroid Build Coastguard Worker     size_t write_position_;
310*789431f2SAndroid Build Coastguard Worker };
311*789431f2SAndroid Build Coastguard Worker 
312*789431f2SAndroid Build Coastguard Worker }  // namespace keymaster
313