On Tue, 25 Oct 2022 at 07:32, Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > > On Mon, Oct 24, 2022 at 08:30:52AM +0200, Ard Biesheuvel wrote: > > The former concern is addressed trivially, given that the function call > > API uses 32-bit signed types for the input lengths. It is still up to > > the caller to avoid IV reuse in general, but this is not something we > > can police at the implementation level. > > This doesn't seem to have been any note left about this in the code itself. > Sizes are usually size_t, so if another type is used intentionally, that should > be carefully documented. > > Also, does it really need to be signed? > I'll add a comment in the code where the counter increment occurs. Using int is easier because I can use signed comparison with 0 to decide whether we are done. We don't need the range so unless someone feels using unsigned int is essential here, I am going to leave it as is. > > +int __must_check aesgcm_decrypt(const struct aesgcm_ctx *ctx, u8 *dst, > > + const u8 *src, int crypt_len, const u8 *assoc, > > + int assoc_len, const u8 iv[GCM_AES_IV_SIZE], > > + const u8 *authtag); > > This returns 0 or -EBADMSG, which is inconsistent with > chacha20poly1305_decrypt() which returns a bool. It would be nice if the > different algorithms would use consistent conventions. > I'll change that.
