andreacavalli/rocksdb
0
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Fix AlignedBuffer's usage in Encryption Env (#5396)

Browse Source 
Summary:
The usage of `AlignedBuffer` in env_encryption.cc writes and reads to/from the AlignedBuffer's internal buffer directly without going through AlignedBuffer's APIs (like `Append` and `Read`), causing encapsulation to break in some cases. The writes are especially problematic as after the data is written to the buffer (directly using either memmove or memcpy), the size of the buffer is not updated ... causing the AlignedBuffer to lose track of the encapsulated buffer's current size.
Fixed this by updating the buffer size after every write.

Todo for later:
Add an overloaded method to AlignedBuffer to support a memmove in addition to a memcopy. Encryption env does a memmove, and hence I couldn't switch to using `AlignedBuffer.Append()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5396

Test Plan: `make check`

Differential Revision: D15764756

Pulled By: sagar0

fbshipit-source-id: 2e24b52bd3b4b5056c5c1da157f91ddf89370183
This commit is contained in:
Sagar Vemuri 2019-06-19 16:42:59 -07:00 committed by Facebook Github Bot
parent 5830c619d5
commit 68614a9608
1 changed files with 49 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
env/env_encryption.cc vendored
View File

@ -204,12 +204,15 @@ class EncryptedWritableFile : public WritableFileWrapper {
// Encrypt in cloned buffer
buf.Alignment(GetRequiredBufferAlignment());
buf.AllocateNewBuffer(data.size());
// TODO (sagar0): Modify AlignedBuffer.Append to allow doing a memmove
// so that the next two lines can be replaced with buf.Append().
memmove(buf.BufferStart(), data.data(), data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), data.size());
buf.Size(data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), buf.CurrentSize());
if (!status.ok()) {
return status;
}
dataToAppend = Slice(buf.BufferStart(), data.size());
dataToAppend = Slice(buf.BufferStart(), buf.CurrentSize());
}
status = file_->Append(dataToAppend);
if (!status.ok()) {
@ -228,11 +231,12 @@ class EncryptedWritableFile : public WritableFileWrapper {
buf.Alignment(GetRequiredBufferAlignment());
buf.AllocateNewBuffer(data.size());
memmove(buf.BufferStart(), data.data(), data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), data.size());
buf.Size(data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), buf.CurrentSize());
if (!status.ok()) {
return status;
}
dataToAppend = Slice(buf.BufferStart(), data.size());
dataToAppend = Slice(buf.BufferStart(), buf.CurrentSize());
}
status = file_->PositionedAppend(dataToAppend, offset);
if (!status.ok()) {
@ -332,11 +336,12 @@ class EncryptedRandomRWFile : public RandomRWFile {
buf.Alignment(GetRequiredBufferAlignment());
buf.AllocateNewBuffer(data.size());
memmove(buf.BufferStart(), data.data(), data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), data.size());
buf.Size(data.size());
status = stream_->Encrypt(offset, buf.BufferStart(), buf.CurrentSize());
if (!status.ok()) {
return status;
}
dataToWrite = Slice(buf.BufferStart(), data.size());
dataToWrite = Slice(buf.BufferStart(), buf.CurrentSize());
}
status = file_->Write(offset, dataToWrite);
return status;
@ -400,6 +405,7 @@ class EncryptedEnv : public EnvWrapper {
if (!status.ok()) {
return status;
}
prefixBuf.Size(prefixLength);
}
// Create cipher stream
std::unique_ptr<BlockAccessCipherStream> stream;
@ -437,6 +443,7 @@ class EncryptedEnv : public EnvWrapper {
if (!status.ok()) {
return status;
}
prefixBuf.Size(prefixLength);
}
// Create cipher stream
std::unique_ptr<BlockAccessCipherStream> stream;
@ -471,7 +478,8 @@ class EncryptedEnv : public EnvWrapper {
prefixBuf.Alignment(underlying->GetRequiredBufferAlignment());
prefixBuf.AllocateNewBuffer(prefixLength);
provider_->CreateNewPrefix(fname, prefixBuf.BufferStart(), prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixLength);
prefixBuf.Size(prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixBuf.CurrentSize());
// Write prefix
status = underlying->Append(prefixSlice);
if (!status.ok()) {
@ -517,7 +525,8 @@ class EncryptedEnv : public EnvWrapper {
prefixBuf.Alignment(underlying->GetRequiredBufferAlignment());
prefixBuf.AllocateNewBuffer(prefixLength);
provider_->CreateNewPrefix(fname, prefixBuf.BufferStart(), prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixLength);
prefixBuf.Size(prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixBuf.CurrentSize());
// Write prefix
status = underlying->Append(prefixSlice);
if (!status.ok()) {
@ -558,7 +567,8 @@ class EncryptedEnv : public EnvWrapper {
prefixBuf.Alignment(underlying->GetRequiredBufferAlignment());
prefixBuf.AllocateNewBuffer(prefixLength);
provider_->CreateNewPrefix(fname, prefixBuf.BufferStart(), prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixLength);
prefixBuf.Size(prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixBuf.CurrentSize());
// Write prefix
status = underlying->Append(prefixSlice);
if (!status.ok()) {
@ -609,10 +619,12 @@ class EncryptedEnv : public EnvWrapper {
if (!status.ok()) {
return status;
}
prefixBuf.Size(prefixLength);
} else {
// File is new, initialize & write prefix
provider_->CreateNewPrefix(fname, prefixBuf.BufferStart(), prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixLength);
prefixBuf.Size(prefixLength);
prefixSlice = Slice(prefixBuf.BufferStart(), prefixBuf.CurrentSize());
// Write prefix
status = underlying->Write(0, prefixSlice);
if (!status.ok()) {
@ -670,7 +682,6 @@ class EncryptedEnv : public EnvWrapper {
EncryptionProvider *provider_;
};
// Returns an Env that encrypts data when stored on disk and decrypts data when
// read from disk.
Env* NewEncryptedEnv(Env* base_env, EncryptionProvider* provider) {