Function zio_decrypt

freebsd/contrib/openzfs/module/zfs/zio.c:455–584

}

static void
zio_decrypt(zio_t *zio, abd_t *data, uint64_t size)
{
	int ret;
	void *tmp;
	blkptr_t *bp = zio->io_bp;
	spa_t *spa = zio->io_spa;
	uint64_t dsobj = zio->io_bookmark.zb_objset;
	uint64_t lsize = BP_GET_LSIZE(bp);
	dmu_object_type_t ot = BP_GET_TYPE(bp);
	uint8_t salt[ZIO_DATA_SALT_LEN];
	uint8_t iv[ZIO_DATA_IV_LEN];
	uint8_t mac[ZIO_DATA_MAC_LEN];
	boolean_t no_crypt = B_FALSE;

	ASSERT(BP_USES_CRYPT(bp));
	ASSERT3U(size, !=, 0);

	if (zio->io_error != 0)
		return;

	/*
	 * Verify the cksum of MACs stored in an indirect bp. It will always
	 * be possible to verify this since it does not require an encryption
	 * key.
	 */
	if (BP_HAS_INDIRECT_MAC_CKSUM(bp)) {
		zio_crypt_decode_mac_bp(bp, mac);

		if (BP_GET_COMPRESS(bp) != ZIO_COMPRESS_OFF) {
			/*
			 * We haven't decompressed the data yet, but
			 * zio_crypt_do_indirect_mac_checksum() requires
			 * decompressed data to be able to parse out the MACs
			 * from the indirect block. We decompress it now and
			 * throw away the result after we are finished.
			 */
			tmp = zio_buf_alloc(lsize);
			ret = zio_decompress_data(BP_GET_COMPRESS(bp),
			    zio->io_abd, tmp, zio->io_size, lsize,
			    &zio->io_prop.zp_complevel);
			if (ret != 0) {
				ret = SET_ERROR(EIO);
				goto error;
			}
			ret = zio_crypt_do_indirect_mac_checksum(B_FALSE,
			    tmp, lsize, BP_SHOULD_BYTESWAP(bp), mac);
			zio_buf_free(tmp, lsize);
		} else {
			ret = zio_crypt_do_indirect_mac_checksum_abd(B_FALSE,
			    zio->io_abd, size, BP_SHOULD_BYTESWAP(bp), mac);
		}
		abd_copy(data, zio->io_abd, size);

		if (zio_injection_enabled && ot != DMU_OT_DNODE && ret == 0) {
			ret = zio_handle_decrypt_injection(spa,
			    &zio->io_bookmark, ot, ECKSUM);
		}