This patch defines the behaviour of AD in the new interface more clearly. In particular, it specifies that if the user must copy the AD to the destination manually when src != dst if they wish to guarantee that the destination buffer contains a copy of the AD. The reason for this is that otherwise every AEAD implementation would have to perform such a copy when src != dst. In reality most users do in-place processing where src == dst so this is not an issue. This patch also kills some remaining references to cryptoff. Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> --- include/crypto/aead.h | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/include/crypto/aead.h b/include/crypto/aead.h index 94141dc..61306ed 100644 --- a/include/crypto/aead.h +++ b/include/crypto/aead.h @@ -473,8 +473,15 @@ static inline void aead_request_set_callback(struct aead_request *req, * destination is the ciphertext. For a decryption operation, the use is * reversed - the source is the ciphertext and the destination is the plaintext. * - * For both src/dst the layout is associated data, skipped data, - * plain/cipher text, authentication tag. + * For both src/dst the layout is associated data, plain/cipher text, + * authentication tag. + * + * The content of the AD in the destination buffer after processing + * will either be untouched, or it will contain a copy of the AD + * from the source buffer. In order to ensure that it always has + * a copy of the AD, the user must copy the AD over either before + * or after processing. Of course this is not relevant if the user + * is doing in-place processing where src == dst. * * IMPORTANT NOTE AEAD requires an authentication tag (MAC). For decryption, * the caller must concatenate the ciphertext followed by the @@ -525,8 +532,7 @@ static inline void aead_request_set_assoc(struct aead_request *req, * @assoclen: number of bytes in associated data * * Setting the AD information. This function sets the length of - * the associated data and the number of bytes to skip after it to - * access the plain/cipher text. + * the associated data. */ static inline void aead_request_set_ad(struct aead_request *req, unsigned int assoclen) -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
