static int encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
struct crypto_blkcipher *tfm = desc->tfm;
struct salsa20_ctx *ctx = crypto_blkcipher_ctx(tfm);
int err;
blkcipher_walk_init(&walk, dst, src, nbytes);
err = blkcipher_walk_virt_block(desc, &walk, 64);
salsa20_ivsetup(ctx, walk.iv);
while (walk.nbytes >= 64) {
salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
walk.dst.virt.addr,
walk.nbytes - (walk.nbytes % 64));
err = blkcipher_walk_done(desc, &walk, walk.nbytes % 64);
}
if (walk.nbytes) {
salsa20_encrypt_bytes(ctx, walk.src.virt.addr,
walk.dst.virt.addr, walk.nbytes);
err = blkcipher_walk_done(desc, &walk, 0);
}
return err;
}
void wasp_set_salsa20_iv( wasp_salsa20_key key, wasp_string iv ){
int ivlen = wasp_string_length( iv );
if( ivlen != 8 )
wasp_errf( wasp_es_vm, "si",
"Salsa20 IVs must be 8 bytes long", ivlen );
salsa20_ivsetup( & key->context, wasp_sf_string( iv ) );
}
