Hi Herbert, On 08/13/2015 11:26 PM, Herbert Xu wrote: > On Thu, Aug 13, 2015 at 11:14:11PM -0700, Tadeusz Struk wrote: >> >> Right, but we don't need that anymore. > > Why not? If you reduce the size without moving the buffer wouldn't > it begin with a bunch of zeroes and wouldn't you lose the real bytes > at the end? Yes, that was wrong, sorry. The reason I wanted to change it is that the SW implementation can return a number with leading zeros. This is because mpi_read_buffer() returns the whole thing. Because the format of the module signature starts with 0x00, 0x01 the two implementations return a different thing. For instance SW returned a 512 bytes number starting with 0x00, 0x01 and HW returned 511 bytes number without the 0x00 at the beginning. Technically both are correct, but then the rsa_signture_verify() needs to check for both cases, which is not ideal. To make it return the same thing as SW we can do something like this: ---8<--- Allow for leading zeros in output to make it exactly the same as the SW implementation. Change memcpy to memmove because the copy is done within the same buffer. diff --git a/drivers/crypto/qat/qat_common/qat_asym_algs.c b/drivers/crypto/qat/qat_common/qat_asym_algs.c index fe352a6..cc450fa 100644 --- a/drivers/crypto/qat/qat_common/qat_asym_algs.c +++ b/drivers/crypto/qat/qat_common/qat_asym_algs.c @@ -118,7 +118,13 @@ static void qat_rsa_cb(struct icp_qat_fw_pke_resp *resp) struct device *dev = &GET_DEV(req->ctx->inst->accel_dev); int err = ICP_QAT_FW_PKE_RESP_PKE_STAT_GET( resp->pke_resp_hdr.comn_resp_flags); - char *ptr = areq->dst; +#if BYTES_PER_MPI_LIMB == 4 + u32 *ptr = areq->dst; +#elif BYTES_PER_MPI_LIMB == 8 + u64 *ptr = areq->dst; +#else +#error please implement for this limb size. +#endif err = (err == ICP_QAT_FW_COMN_STATUS_FLAG_OK) ? 0 : -EINVAL; @@ -140,12 +146,12 @@ static void qat_rsa_cb(struct icp_qat_fw_pke_resp *resp) areq->dst_len = req->ctx->key_sz; /* Need to set the corect length of the output */ while (!(*ptr) && areq->dst_len) { - areq->dst_len--; + areq->dst_len -= sizeof(*ptr); ptr++; } if (areq->dst_len != req->ctx->key_sz) - memcpy(areq->dst, ptr, areq->dst_len); + memmove(areq->dst, ptr, areq->dst_len); akcipher_request_complete(areq, err); } -- 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