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Jason2866Jason2866
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Revert crypt update PR espressif#5807 (#326)
* Update Updater.cpp * Update Update.h
1 parent 8787844 commit a5fe8e6

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2 files changed

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-211
lines changed

2 files changed

+1
-211
lines changed

Diff for: ‎libraries/Update/src/Update.h

+1-48
Original file line numberDiff line numberDiff line change
@@ -5,7 +5,6 @@
55
#include <MD5Builder.h>
66
#include <functional>
77
#include "esp_partition.h"
8-
#include "aes/esp_aes.h"
98

109
#define UPDATE_ERROR_OK (0)
1110
#define UPDATE_ERROR_WRITE (1)
@@ -20,23 +19,14 @@
2019
#define UPDATE_ERROR_NO_PARTITION (10)
2120
#define UPDATE_ERROR_BAD_ARGUMENT (11)
2221
#define UPDATE_ERROR_ABORT (12)
23-
#define UPDATE_ERROR_DECRYPT (13)
2422

2523
#define UPDATE_SIZE_UNKNOWN 0xFFFFFFFF
2624

2725
#define U_FLASH 0
2826
#define U_SPIFFS 100
2927
#define U_AUTH 200
3028

31-
#define ENCRYPTED_BLOCK_SIZE 16
32-
#define ENCRYPTED_TWEAK_BLOCK_SIZE 32
33-
#define ENCRYPTED_KEY_SIZE 32
34-
35-
#define U_AES_DECRYPT_NONE 0
36-
#define U_AES_DECRYPT_AUTO 1
37-
#define U_AES_DECRYPT_ON 2
38-
#define U_AES_DECRYPT_MODE_MASK 3
39-
#define U_AES_IMAGE_DECRYPTING_BIT 4
29+
#define ENCRYPTED_BLOCK_SIZE 16
4030

4131
#define SPI_SECTORS_PER_BLOCK 16 // usually large erase block is 32k/64k
4232
#define SPI_FLASH_BLOCK_SIZE (SPI_SECTORS_PER_BLOCK*SPI_FLASH_SEC_SIZE)
@@ -58,15 +48,6 @@ class UpdateClass {
5848
*/
5949
bool begin(size_t size=UPDATE_SIZE_UNKNOWN, int command = U_FLASH, int ledPin = -1, uint8_t ledOn = LOW, const char *label = NULL);
6050

61-
/*
62-
Setup decryption configuration
63-
Crypt Key is 32bytes(256bits) block of data, use the same key as used to encrypt image file
64-
Crypt Address, use the same value as used to encrypt image file
65-
Crypt Config, use the same value as used to encrypt image file
66-
Crypt Mode, used to select if image files should be decrypted or not
67-
*/
68-
bool setupCrypt(const uint8_t *cryptKey=0, size_t cryptAddress=0, uint8_t cryptConfig=0xf, int cryptMode=U_AES_DECRYPT_AUTO);
69-
7051
/*
7152
Writes a buffer to the flash and increments the address
7253
Returns the amount written
@@ -94,26 +75,6 @@ class UpdateClass {
9475
*/
9576
bool end(bool evenIfRemaining = false);
9677

97-
/*
98-
sets AES256 key(32 bytes) used for decrypting image file
99-
*/
100-
bool setCryptKey(const uint8_t *cryptKey);
101-
102-
/*
103-
sets crypt mode used on image files
104-
*/
105-
bool setCryptMode(const int cryptMode);
106-
107-
/*
108-
sets address used for decrypting image file
109-
*/
110-
void setCryptAddress(const size_t cryptAddress){ _cryptAddress = cryptAddress & 0x00fffff0; }
111-
112-
/*
113-
sets crypt config used for decrypting image file
114-
*/
115-
void setCryptConfig(const uint8_t cryptConfig){ _cryptCfg = cryptConfig & 0x0f; }
116-
11778
/*
11879
Aborts the running update
11980
*/
@@ -204,8 +165,6 @@ class UpdateClass {
204165
private:
205166
void _reset();
206167
void _abort(uint8_t err);
207-
void _cryptKeyTweak(size_t cryptAddress, uint8_t *tweaked_key);
208-
bool _decryptBuffer();
209168
bool _writeBuffer();
210169
bool _verifyHeader(uint8_t data);
211170
bool _verifyEnd();
@@ -214,8 +173,6 @@ class UpdateClass {
214173

215174

216175
uint8_t _error;
217-
uint8_t *_cryptKey;
218-
uint8_t *_cryptBuffer;
219176
uint8_t *_buffer;
220177
uint8_t *_skipBuffer;
221178
size_t _bufferLen;
@@ -231,10 +188,6 @@ class UpdateClass {
231188

232189
int _ledPin;
233190
uint8_t _ledOn;
234-
235-
uint8_t _cryptMode;
236-
size_t _cryptAddress;
237-
uint8_t _cryptCfg;
238191
};
239192

240193
#if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_UPDATE)

Diff for: ‎libraries/Update/src/Updater.cpp

-163
Original file line numberDiff line numberDiff line change
@@ -31,8 +31,6 @@ static const char * _err2str(uint8_t _error){
3131
return ("Bad Argument");
3232
} else if(_error == UPDATE_ERROR_ABORT){
3333
return ("Aborted");
34-
} else if(_error == UPDATE_ERROR_DECRYPT){
35-
return ("Decryption error");
3634
}
3735
return ("UNKNOWN");
3836
}
@@ -61,20 +59,14 @@ bool UpdateClass::_enablePartition(const esp_partition_t* partition){
6159

6260
UpdateClass::UpdateClass()
6361
: _error(0)
64-
, _cryptKey(0)
65-
, _cryptBuffer(0)
6662
, _buffer(0)
67-
, _skipBuffer(0)
6863
, _bufferLen(0)
6964
, _size(0)
7065
, _progress_callback(NULL)
7166
, _progress(0)
7267
, _paroffset(0)
7368
, _command(U_FLASH)
7469
, _partition(NULL)
75-
, _cryptMode(U_AES_DECRYPT_AUTO)
76-
, _cryptAddress(0)
77-
, _cryptCfg(0xf)
7870
{
7971
}
8072

@@ -91,7 +83,6 @@ void UpdateClass::_reset() {
9183
delete[] _skipBuffer;
9284
}
9385

94-
_cryptBuffer = nullptr;
9586
_buffer = nullptr;
9687
_skipBuffer = nullptr;
9788
_bufferLen = 0;
@@ -185,48 +176,6 @@ bool UpdateClass::begin(size_t size, int command, int ledPin, uint8_t ledOn, con
185176
return true;
186177
}
187178

188-
bool UpdateClass::setupCrypt(const uint8_t *cryptKey, size_t cryptAddress, uint8_t cryptConfig, int cryptMode){
189-
if(setCryptKey(cryptKey)){
190-
if(setCryptMode(cryptMode)){
191-
setCryptAddress(cryptAddress);
192-
setCryptConfig(cryptConfig);
193-
return true;
194-
}
195-
}
196-
return false;
197-
}
198-
199-
bool UpdateClass::setCryptKey(const uint8_t *cryptKey){
200-
if(!cryptKey){
201-
if (_cryptKey){
202-
delete[] _cryptKey;
203-
_cryptKey = 0;
204-
log_d("AES key unset");
205-
}
206-
return false; //key cleared, no key to decrypt with
207-
}
208-
//initialize
209-
if(!_cryptKey){
210-
_cryptKey = new (std::nothrow) uint8_t[ENCRYPTED_KEY_SIZE];
211-
}
212-
if(!_cryptKey){
213-
log_e("new failed");
214-
return false;
215-
}
216-
memcpy(_cryptKey, cryptKey, ENCRYPTED_KEY_SIZE);
217-
return true;
218-
}
219-
220-
bool UpdateClass::setCryptMode(const int cryptMode){
221-
if(cryptMode >= U_AES_DECRYPT_NONE && cryptMode <= U_AES_DECRYPT_ON){
222-
_cryptMode = cryptMode;
223-
}else{
224-
log_e("bad crypt mode arguement %i", cryptMode);
225-
return false;
226-
}
227-
return true;
228-
}
229-
230179
void UpdateClass::_abort(uint8_t err){
231180
_reset();
232181
_error = err;
@@ -236,119 +185,7 @@ void UpdateClass::abort(){
236185
_abort(UPDATE_ERROR_ABORT);
237186
}
238187

239-
void UpdateClass::_cryptKeyTweak(size_t cryptAddress, uint8_t *tweaked_key){
240-
memcpy(tweaked_key, _cryptKey, ENCRYPTED_KEY_SIZE );
241-
if(_cryptCfg == 0) return; //no tweaking needed, use crypt key as-is
242-
243-
const uint8_t pattern[] = { 23, 23, 23, 14, 23, 23, 23, 12, 23, 23, 23, 10, 23, 23, 23, 8 };
244-
int pattern_idx = 0;
245-
int key_idx = 0;
246-
int bit_len = 0;
247-
uint32_t tweak = 0;
248-
cryptAddress &= 0x00ffffe0; //bit 23-5
249-
cryptAddress <<= 8; //bit23 shifted to bit31(MSB)
250-
while(pattern_idx < sizeof(pattern)){
251-
tweak = cryptAddress<<(23 - pattern[pattern_idx]); //bit shift for small patterns
252-
// alternative to: tweak = rotl32(tweak,8 - bit_len);
253-
tweak = (tweak<<(8 - bit_len)) | (tweak>>(24 + bit_len)); //rotate to line up with end of previous tweak bits
254-
bit_len += pattern[pattern_idx++] - 4; //add number of bits in next pattern(23-4 = 19bits = 23bit to 5bit)
255-
while(bit_len > 7){
256-
tweaked_key[key_idx++] ^= tweak; //XOR byte
257-
// alternative to: tweak = rotl32(tweak, 8);
258-
tweak = (tweak<<8) | (tweak>>24); //compiler should optimize to use rotate(fast)
259-
bit_len -=8;
260-
}
261-
tweaked_key[key_idx] ^= tweak; //XOR remaining bits, will XOR zeros if no remaining bits
262-
}
263-
if(_cryptCfg == 0xf) return; //return with fully tweaked key
264-
265-
//some of tweaked key bits need to be restore back to crypt key bits
266-
const uint8_t cfg_bits[] = { 67, 65, 63, 61 };
267-
key_idx = 0;
268-
pattern_idx = 0;
269-
while(key_idx < ENCRYPTED_KEY_SIZE){
270-
bit_len += cfg_bits[pattern_idx];
271-
if( (_cryptCfg & (1<<pattern_idx)) == 0 ){ //restore crypt key bits
272-
while(bit_len > 0){
273-
if( bit_len > 7 || ((_cryptCfg & (2<<pattern_idx)) == 0) ){ //restore a crypt key byte
274-
tweaked_key[key_idx] = _cryptKey[key_idx];
275-
}else{ //MSBits restore crypt key bits, LSBits keep as tweaked bits
276-
tweaked_key[key_idx] &= (0xff>>bit_len);
277-
tweaked_key[key_idx] |= (_cryptKey[key_idx] & (~(0xff>>bit_len)) );
278-
}
279-
key_idx++;
280-
bit_len -= 8;
281-
}
282-
}else{ //keep tweaked key bits
283-
while(bit_len > 0){
284-
if( bit_len <8 && ((_cryptCfg & (2<<pattern_idx)) == 0) ){ //MSBits keep as tweaked bits, LSBits restore crypt key bits
285-
tweaked_key[key_idx] &= (~(0xff>>bit_len));
286-
tweaked_key[key_idx] |= (_cryptKey[key_idx] & (0xff>>bit_len));
287-
}
288-
key_idx++;
289-
bit_len -= 8;
290-
}
291-
}
292-
pattern_idx++;
293-
}
294-
}
295-
296-
bool UpdateClass::_decryptBuffer(){
297-
if(!_cryptKey){
298-
log_w("AES key not set");
299-
return false;
300-
}
301-
if(_bufferLen%ENCRYPTED_BLOCK_SIZE !=0 ){
302-
log_e("buffer size error");
303-
return false;
304-
}
305-
if(!_cryptBuffer){
306-
_cryptBuffer = new (std::nothrow) uint8_t[ENCRYPTED_BLOCK_SIZE];
307-
}
308-
if(!_cryptBuffer){
309-
log_e("new failed");
310-
return false;
311-
}
312-
uint8_t tweaked_key[ENCRYPTED_KEY_SIZE]; //tweaked crypt key
313-
int done = 0;
314-
315-
esp_aes_context ctx; //initialize AES
316-
esp_aes_init( &ctx );
317-
while((_bufferLen - done) >= ENCRYPTED_BLOCK_SIZE){
318-
for(int i=0; i < ENCRYPTED_BLOCK_SIZE; i++) _cryptBuffer[(ENCRYPTED_BLOCK_SIZE - 1) - i] = _buffer[i + done]; //reverse order 16 bytes to decrypt
319-
if( ((_cryptAddress + _progress + done) % ENCRYPTED_TWEAK_BLOCK_SIZE) == 0 || done == 0 ){
320-
_cryptKeyTweak(_cryptAddress + _progress + done, tweaked_key); //update tweaked crypt key
321-
if( esp_aes_setkey( &ctx, tweaked_key, 256 ) ){
322-
return false;
323-
}
324-
}
325-
if( esp_aes_crypt_ecb( &ctx, ESP_AES_ENCRYPT, _cryptBuffer, _cryptBuffer ) ){ //use ESP_AES_ENCRYPT to decrypt flash code
326-
return false;
327-
}
328-
for(int i=0; i < ENCRYPTED_BLOCK_SIZE; i++) _buffer[i + done] = _cryptBuffer[(ENCRYPTED_BLOCK_SIZE - 1) - i]; //reverse order 16 bytes from decrypt
329-
done += ENCRYPTED_BLOCK_SIZE;
330-
}
331-
return true;
332-
}
333-
334188
bool UpdateClass::_writeBuffer(){
335-
//first bytes of loading image, check to see if loading image needs decrypting
336-
if(!_progress){
337-
_cryptMode &= U_AES_DECRYPT_MODE_MASK;
338-
if( ( _cryptMode == U_AES_DECRYPT_ON )
339-
|| ((_command == U_FLASH) && (_cryptMode & U_AES_DECRYPT_AUTO) && (_buffer[0] != ESP_IMAGE_HEADER_MAGIC))
340-
){
341-
_cryptMode |= U_AES_IMAGE_DECRYPTING_BIT; //set to decrypt the loading image
342-
log_d("Decrypting OTA Image");
343-
}
344-
}
345-
//check if data in buffer needs decrypting
346-
if( _cryptMode & U_AES_IMAGE_DECRYPTING_BIT ){
347-
if( !_decryptBuffer() ){
348-
_abort(UPDATE_ERROR_DECRYPT);
349-
return false;
350-
}
351-
}
352189
//first bytes of new firmware
353190
uint8_t skip = 0;
354191
if(!_progress && _command == U_FLASH){

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