diff options
Diffstat (limited to 'openpgp/src/crypto/aead.rs')
| -rw-r--r-- | openpgp/src/crypto/aead.rs | 28 |
1 files changed, 18 insertions, 10 deletions
diff --git a/openpgp/src/crypto/aead.rs b/openpgp/src/crypto/aead.rs index 17153aa1..ac658046 100644 --- a/openpgp/src/crypto/aead.rs +++ b/openpgp/src/crypto/aead.rs @@ -59,6 +59,14 @@ pub trait Aead : seal::Sealed { fn digest_size(&self) -> usize; } +/// Whether AEAD cipher is used for data encryption or decryption. +pub(crate) enum CipherOp { + /// Cipher is used for data encryption. + Encrypt, + /// Cipher is used for data decryption. + Decrypt, +} + impl AEADAlgorithm { /// Returns the digest size of the AEAD algorithm. pub fn digest_size(&self) -> Result<usize> { @@ -168,7 +176,7 @@ impl<'a> Decryptor<'a> { } } - fn make_aead(&mut self) -> Result<Box<dyn Aead>> { + fn make_aead(&mut self, op: CipherOp) -> Result<Box<dyn Aead>> { // The chunk index is XORed into the IV. let chunk_index: [u8; 8] = self.chunk_index.to_be_bytes(); @@ -189,7 +197,7 @@ impl<'a> Decryptor<'a> { } // Instantiate the AEAD cipher. - let aead = self.aead.context(self.sym_algo, &self.key, &self.iv)?; + let aead = self.aead.context(self.sym_algo, &self.key, &self.iv, op)?; // Restore the IV. for (i, o) in &mut self.iv[iv_len - 8..].iter_mut() @@ -265,7 +273,7 @@ impl<'a> Decryptor<'a> { let final_digest_size = self.digest_size; for _ in 0..n_chunks { - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Decrypt)?; // Digest the associated data. self.hash_associated_data(&mut aead, false); @@ -356,7 +364,7 @@ impl<'a> Decryptor<'a> { if check_final_tag { // We read the whole ciphertext, now check the final digest. - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Decrypt)?; self.hash_associated_data(&mut aead, true); aead.digest(&mut digest); @@ -583,7 +591,7 @@ impl<W: io::Write> Encryptor<W> { } } - fn make_aead(&mut self) -> Result<Box<dyn Aead>> { + fn make_aead(&mut self, op: CipherOp) -> Result<Box<dyn Aead>> { // The chunk index is XORed into the IV. let chunk_index: [u8; 8] = self.chunk_index.to_be_bytes(); @@ -604,7 +612,7 @@ impl<W: io::Write> Encryptor<W> { } // Instantiate the AEAD cipher. - let aead = self.aead.context(self.sym_algo, &self.key, &self.iv)?; + let aead = self.aead.context(self.sym_algo, &self.key, &self.iv, op)?; // Restore the IV. for (i, o) in &mut self.iv[iv_len - 8..].iter_mut() @@ -636,7 +644,7 @@ impl<W: io::Write> Encryptor<W> { // And possibly encrypt the chunk. if self.buffer.len() == self.chunk_size { - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Encrypt)?; self.hash_associated_data(&mut aead, false); let inner = self.inner.as_mut().unwrap(); @@ -658,7 +666,7 @@ impl<W: io::Write> Encryptor<W> { for chunk in buf.chunks(self.chunk_size) { if chunk.len() == self.chunk_size { // Complete chunk. - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Encrypt)?; self.hash_associated_data(&mut aead, false); let inner = self.inner.as_mut().unwrap(); @@ -686,7 +694,7 @@ impl<W: io::Write> Encryptor<W> { pub fn finish(&mut self) -> Result<W> { if let Some(mut inner) = self.inner.take() { if self.buffer.len() > 0 { - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Encrypt)?; self.hash_associated_data(&mut aead, false); // Encrypt the chunk. @@ -704,7 +712,7 @@ impl<W: io::Write> Encryptor<W> { } // Write final digest. - let mut aead = self.make_aead()?; + let mut aead = self.make_aead(CipherOp::Decrypt)?; self.hash_associated_data(&mut aead, true); aead.digest(&mut self.scratch[..self.digest_size]); inner.write_all(&self.scratch[..self.digest_size])?; |