使用管道加密文件 [英] Use of Pipelines to encrypt a file
问题描述
我想使用AES加密一个文件。
1.）只要做到这一点就够了：
EAX&AES> ::加密加密器;
encryptor.SetKeyWithIV（derived.data（），16，ivb，ivb.size（））;
FileSource f（source，新的AuthenticatedEncryptionFilter（encryptor，new FileSink（deststination）））;
2。）如果我有一个巨大的输入文件，这种方法会自动对块中的文件进行加密吗？
3。）如果不存在，会自动创建输出文件吗？
编辑：
好的，我得到了我的欢迎。
2.）问题仍然存在，我有一个新的：
我可以告诉它跳过文件的前24个字节吗？
EAX< AES> ::加密加密器;
encryptor.SetKeyWithIV（derived.data（），16，ivb，ivb.size（））;
FileSource f（source，新的AuthenticatedEncryptionFilter（encryptor，new FileSink（deststination）））;
关闭。 AuthenticatedEncryptionFilter 将被强制为 bool pumpAll 参数 FileSink 。所以你需要：
FileSource f（source，true，new AuthenticatedEncryptionFilter（encryptor，new FileSink（deststination）） ）;
另请参阅 FileSource 在Crypto ++维基。而手册中的 FileSource类参考也可能会引起关注。 p>
如果我有一个巨大的输入文件，这种方法会自动加密块中的文件吗？ / p>
是的。在内部，Crypto ++将在4096字节的IIRC中阻塞或块处理。最近的一个关于这个问题的讨论发生在邮件列表中的 ios在加密期间锁定。
允许您进行阻止在帖子中提供。您可以使用它来限制处理，如果需要，可以更新进度条或生成处理器。
如果不存在，会自动创建输出文件吗？
是的。 FileSource 只是一个 std :: ifstream 包装器，而 FileSink 只是一个 std :: ofstream 包装器。
再次，这里是维基页面： p>
我可以告诉它跳过文件的前24个字节吗？
是的。在这种情况下，请使用 bool pumpAll 并将其设置为 false 。然后执行以下操作：
FileSource fs（source，false，new AuthenticatedEncryptionFilter（...））;
fs.Skip（24）;
size_t remaining =<文件大小> ;;
size_t BLOCK_SIZE = 512;
while（remaining&&fs.SourceExhausted（））
{
const unsigned int req = STDMIN（remaining，BLOCK_SIZE）;
fs.Pump（req）;
fs.Flush（false）;
剩余 - = req;
}
或者，您可以：
pre>
FileSource fs（source，false，new AuthenticatedEncryptionFilter（...））;
fs.Skip（24）;
fs.PumpAll（）;
另请参阅 FileSource类参考。 跳过是 BufferedTransformation 的一部分;而$ code> PumpAll 是 Source 的一部分。
还有涵盖EAX模式和认证的{en | de} cryption过滤器的wiki页面。请参阅：
甚至还有一个使用类似Java的Init / Update / Final的页面：
< hr>
以下程序使用 CFB_Mode< AES> 它很容易交换另一种密码和模式。它还演示了如何在堆栈中放置对象并将其用于管道中，而不是使用 新建 c 。
int main（int argc，char * argv []）
{
static const unsigned int BIG_SIZE = 2U * 1024U * 1024U;
static const unsigned int BLOCK_SIZE = 4096U;
try
{
SecByteBlock key（32）;
OS_GenerateRandomBlock（false，key.data（），key.size（））;
// cout<<< 关键：;
// ArraySource as（key.data（），key.size（），true，new HexEncoder（new FileSink（cout）））;
// cout<<< ENDL;
CFB_Mode< AES> ::加密enc;
enc.SetKeyWithIV（key.data（），key.size（），key.data（））;
MeterFilter meter;
StreamTransformationFilter stf（enc）;
FileSource源（/ dev / zero，false）;
FileSink sink（zero.enc）;
source.Attach（new Redirector（stf））;
stf.Attach（new Redirector（meter））;
meter.Attach（new Redirector（sink））;
unsigned int remaining = BIG_SIZE;
while（剩余&！source.SourceExhausted（））
{
if（剩余％（1024）== 0）
{
cout< < 处理：< meter.GetTotalBytes（）<< ENDL;
}
const unsigned int req = STDMIN（剩余，BLOCK_SIZE）;
source.Pump（req）;
source.Flush（false）;
剩余 - = req;
}
}
catch（const Exception& ex）
{
cerr<< ex.what（）<< ENDL;
}
return 0;
}
I have just startet working with crypto++ and i have a question about the piplenes and how to use them to encrypt a file.
I want to use AES to encrypt a file.
1.)Would it be enough to just do:
EAX<AES>::Encryption encryptor;
encryptor.SetKeyWithIV(derived.data(), 16, ivb, ivb.size());
FileSource f("source", new AuthenticatedEncryptionFilter(encryptor,new FileSink("deststination")));
2.) If i have a huge input file, will this approach automaticly encrypt the files in blocks?
3.) Would this automaticly create the output file if it is not there?
EDIT:
Ok, i got it to wok with my approch.
The 2.) Question remains and i have a new one:
Can I tell it to skip the first 24 bytes of the file?
EAX<AES>::Encryption encryptor; encryptor.SetKeyWithIV(derived.data(), 16, ivb, ivb.size()); FileSource f("source", new AuthenticatedEncryptionFilter(encryptor,new FileSink("deststination")));
Close. The AuthenticatedEncryptionFilter will be coerced to the bool pumpAll parameter of FileSink. So you need:
FileSource f("source", true, new AuthenticatedEncryptionFilter(encryptor,new FileSink("deststination")));
Also see FileSource on the Crypto++ wiki. And the FileSource Class Reference from the manual might be of interest, too.
If i have a huge input file, will this approach automatically encrypt the files in blocks?
Yes. Internally, Crypto++ will "block" or "chunk" the processing in 4096-bytes, IIRC. A recent discussion about it occurred on the mailing list at ios locking up during encryption.
A program that allows you to do the blocking is provided in the post. You can use it to throttle the processing, a place to update a progress bar or yield the processor, if needed. Its reproduced below.
Would this automatically create the output file if it is not there?
Yes. The FileSource is just a std::ifstream wrapper, while a FileSink is just a std::ofstream wrapper.
Again, here are the wiki pages:
Can I tell it to skip the first 24 bytes of the file?
Yes. In this case, use bool pumpAll and set it to false. Then do something like:
FileSource fs("source", false, new AuthenticatedEncryptionFilter(...));
fs.Skip(24);
size_t remaining = <size of file>;
size_t BLOCK_SIZE = 512;
while(remaining && !fs.SourceExhausted())
{
const unsigned int req = STDMIN(remaining, BLOCK_SIZE);
fs.Pump(req);
fs.Flush(false);
remaining -= req;
}
Or, you can:
FileSource fs("source", false, new AuthenticatedEncryptionFilter(...));
fs.Skip(24);
fs.PumpAll();
Also see FileSource Class Reference in the manual. Skip is part of BufferedTransformation; and PumpAll is part of Source.
There are also wiki pages covering EAX mode and the authenticated {en|de}cryption filters. See:
There's even a page on using a Java-like Init/Update/Final at:
The program below uses CFB_Mode<AES>, but its easy enough to swap in another cipher and mode. It also demonstrates how to place objects on the stack and use them in a pipeline rather than creating them on the heap with new.
int main(int argc, char* argv[])
{
static const unsigned int BIG_SIZE = 2U * 1024U * 1024U;
static const unsigned int BLOCK_SIZE = 4096U;
try
{
SecByteBlock key(32);
OS_GenerateRandomBlock(false, key.data(), key.size());
// cout << "Key: ";
// ArraySource as(key.data(), key.size(), true, new HexEncoder(new FileSink(cout)));
// cout << endl;
CFB_Mode<AES>::Encryption enc;
enc.SetKeyWithIV(key.data(), key.size(), key.data());
MeterFilter meter;
StreamTransformationFilter stf(enc);
FileSource source("/dev/zero", false);
FileSink sink("zero.enc");
source.Attach(new Redirector(stf));
stf.Attach(new Redirector(meter));
meter.Attach(new Redirector(sink));
unsigned int remaining = BIG_SIZE;
while(remaining && !source.SourceExhausted())
{
if(remaining % (1024) == 0)
{
cout << "Processed: " << meter.GetTotalBytes() << endl;
}
const unsigned int req = STDMIN(remaining, BLOCK_SIZE);
source.Pump(req);
source.Flush(false);
remaining -= req;
}
}
catch(const Exception& ex)
{
cerr << ex.what() << endl;
}
return 0;
}
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