Handle LZO compression in --compress framing

Share parse block between comp-lzo and compress.

It seems that --compress sends NO_COMPRESS w/o swapping.

Also suppress redundant LZOIsSupported(), implied by non-nil value
of self.lzo.
This commit is contained in:
Davide De Rosa 2019-03-19 23:19:16 +01:00
parent 4b9ffcfb4e
commit 9d479a9aba
1 changed files with 56 additions and 42 deletions

View File

@ -168,6 +168,42 @@
- (void)setCompressionFraming:(CompressionFramingNative)compressionFraming
{
__weak DataPath *weakSelf = self;
DataPathParseBlock parseCompressedBlock = ^BOOL(uint8_t * _Nonnull payload, NSInteger * _Nonnull payloadOffset, uint8_t * _Nonnull compressionHeader, NSInteger * _Nonnull headerLength, const uint8_t * _Nonnull packet, NSInteger packetLength, NSError * _Nullable __autoreleasing * _Nullable error) {
*compressionHeader = payload[0];
*headerLength = 1;
switch (*compressionHeader) {
case DataPacketNoCompress:
*payloadOffset = 1;
break;
case DataPacketNoCompressSwap:
payload[0] = packet[packetLength - 1];
*payloadOffset = 0;
break;
case DataPacketLZOCompress:
if (!weakSelf.lzo) { // compressed packet unexpected
if (error) {
*error = TunnelKitErrorWithCode(TunnelKitErrorCodeDataPathCompression);
}
return NO;
}
*payloadOffset = 1;
break;
default:
// @"Expected NO_COMPRESS (found %X != %X)", payload[0], DataPacketNoCompress);
if (error) {
*error = TunnelKitErrorWithCode(TunnelKitErrorCodeDataPathCompression);
}
return NO;
}
return YES;
};
switch (compressionFraming) {
case CompressionFramingNativeDisabled: {
self.assemblePayloadBlock = ^(uint8_t * packetDest, NSInteger * packetLengthOffset, NSData * payload) {
@ -184,27 +220,30 @@
}
case CompressionFramingNativeCompress: {
self.assemblePayloadBlock = ^(uint8_t * packetDest, NSInteger * packetLengthOffset, NSData * payload) {
memcpy(packetDest, payload.bytes, payload.length);
packetDest[payload.length] = packetDest[0];
packetDest[0] = DataPacketNoCompressSwap;
*packetLengthOffset = 1;
};
self.parsePayloadBlock = ^BOOL(uint8_t * _Nonnull payload, NSInteger * _Nonnull payloadOffset, uint8_t * _Nonnull compressionHeader, NSInteger * _Nonnull headerLength, const uint8_t * _Nonnull packet, NSInteger packetLength, NSError * _Nullable __autoreleasing * _Nullable error) {
*compressionHeader = payload[0];
if (*compressionHeader != DataPacketNoCompressSwap) {
// @"Expected NO_COMPRESS_SWAP (found %X != %X)", payload[0], DataPacketNoCompressSwap);
*error = TunnelKitErrorWithCode(TunnelKitErrorCodeDataPathCompression);
return NO;
NSData *compressedPayload = [weakSelf.lzo compressedDataWithData:payload error:NULL];
if (compressedPayload) {
packetDest[0] = DataPacketLZOCompress;
*packetLengthOffset = 1 - (payload.length - compressedPayload.length);
payload = compressedPayload;
memcpy(packetDest + 1, payload.bytes, payload.length);
} else {
*packetLengthOffset = 1;
// do not byte swap if compression enabled
if (weakSelf.lzo) {
packetDest[0] = DataPacketNoCompress;
memcpy(packetDest + 1, payload.bytes, payload.length);
} else {
memcpy(packetDest, payload.bytes, payload.length);
packetDest[payload.length] = packetDest[0];
packetDest[0] = DataPacketNoCompressSwap;
}
}
payload[0] = packet[packetLength - 1];
*payloadOffset = 0;
*headerLength = 1;
return YES;
};
self.parsePayloadBlock = parseCompressedBlock;
break;
}
case CompressionFramingNativeCompLZO: {
__weak DataPath *weakSelf = self;
self.assemblePayloadBlock = ^(uint8_t * packetDest, NSInteger * packetLengthOffset, NSData * payload) {
NSData *compressedPayload = [weakSelf.lzo compressedDataWithData:payload error:NULL];
if (compressedPayload) {
@ -217,32 +256,7 @@
}
memcpy(packetDest + 1, payload.bytes, payload.length);
};
self.parsePayloadBlock = ^BOOL(uint8_t * _Nonnull payload, NSInteger * _Nonnull payloadOffset, uint8_t * _Nonnull compressionHeader, NSInteger * _Nonnull headerLength, const uint8_t * _Nonnull packet, NSInteger packetLength, NSError * _Nullable __autoreleasing * _Nullable error) {
*compressionHeader = payload[0];
switch (*compressionHeader) {
case DataPacketNoCompress:
break;
case DataPacketLZOCompress:
if (!LZOIsSupported() || !weakSelf.lzo) { // compressed packet unexpected
if (error) {
*error = TunnelKitErrorWithCode(TunnelKitErrorCodeDataPathCompression);
}
return NO;
}
break;
default:
// @"Expected NO_COMPRESS (found %X != %X)", payload[0], DataPacketNoCompress);
if (error) {
*error = TunnelKitErrorWithCode(TunnelKitErrorCodeDataPathCompression);
}
return NO;
}
*payloadOffset = 1;
*headerLength = 1;
return YES;
};
self.parsePayloadBlock = parseCompressedBlock;
break;
}
}