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using GLib;
namespace Crypto {
public abstract class SymmetricCipherConverter : Converter, Object {
internal SymmetricCipher cipher;
internal size_t attached_taglen;
public abstract ConverterResult convert(uint8[] inbuf, uint8[] outbuf, ConverterFlags flags, out size_t bytes_read, out size_t bytes_written) throws IOError;
public uint8[] get_tag(size_t taglen) throws Error {
return cipher.get_tag(taglen);
}
public void check_tag(uint8[] tag) throws Error {
cipher.check_tag(tag);
}
public void reset() {
cipher.reset();
}
}
public class SymmetricCipherEncrypter : SymmetricCipherConverter {
public SymmetricCipherEncrypter(owned SymmetricCipher cipher, size_t attached_taglen = 0) {
this.cipher = (owned) cipher;
this.attached_taglen = attached_taglen;
}
public override ConverterResult convert(uint8[] inbuf, uint8[] outbuf, ConverterFlags flags, out size_t bytes_read, out size_t bytes_written) throws IOError {
if (inbuf.length > outbuf.length) {
throw new IOError.NO_SPACE("CipherConverter needs at least the size of input as output space");
}
if ((flags & ConverterFlags.INPUT_AT_END) != 0 && inbuf.length + attached_taglen > outbuf.length) {
throw new IOError.NO_SPACE("CipherConverter needs additional output space to attach tag");
}
if (inbuf.length > 0) {
cipher.encrypt(outbuf, inbuf);
}
bytes_read = inbuf.length;
bytes_written = inbuf.length;
if ((flags & ConverterFlags.INPUT_AT_END) != 0) {
if (attached_taglen > 0) {
Memory.copy((uint8*)outbuf + inbuf.length, get_tag(attached_taglen), attached_taglen);
bytes_written = inbuf.length + attached_taglen;
}
return ConverterResult.FINISHED;
}
if ((flags & ConverterFlags.FLUSH) != 0) {
return ConverterResult.FLUSHED;
}
return ConverterResult.CONVERTED;
}
}
public class SymmetricCipherDecrypter : SymmetricCipherConverter {
public SymmetricCipherDecrypter(owned SymmetricCipher cipher, size_t attached_taglen = 0) {
this.cipher = (owned) cipher;
this.attached_taglen = attached_taglen;
}
public override ConverterResult convert(uint8[] inbuf, uint8[] outbuf, ConverterFlags flags, out size_t bytes_read, out size_t bytes_written) throws IOError {
if (inbuf.length > outbuf.length + attached_taglen) {
throw new IOError.NO_SPACE("CipherConverter needs at least the size of input as output space");
}
if ((flags & ConverterFlags.INPUT_AT_END) != 0 && inbuf.length < attached_taglen) {
throw new IOError.PARTIAL_INPUT("CipherConverter needs additional input to read tag");
} else if ((flags & ConverterFlags.INPUT_AT_END) == 0 && inbuf.length < attached_taglen + 1) {
throw new IOError.PARTIAL_INPUT("CipherConverter needs additional input to make sure to not accidentally read tag");
}
inbuf.length -= (int) attached_taglen;
if (inbuf.length > 0) {
cipher.decrypt(outbuf, inbuf);
}
bytes_read = inbuf.length;
bytes_written = inbuf.length;
inbuf.length += (int) attached_taglen;
if ((flags & ConverterFlags.INPUT_AT_END) != 0) {
if (attached_taglen > 0) {
print("Checking tag\n");
check_tag(inbuf[(inbuf.length - attached_taglen):inbuf.length]);
print("tag ok\n");
bytes_read = inbuf.length;
}
return ConverterResult.FINISHED;
}
if ((flags & ConverterFlags.FLUSH) != 0) {
return ConverterResult.FLUSHED;
}
return ConverterResult.CONVERTED;
}
}
}
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