1. Can any one point me which RFC describe how exactly authencesn should work?

2. I test Ipsec with "esp=aes256-sha512-esn!" options and found compatibility 
issue between kernel software crypto and talitos driver.
Talitos <---->talitos                           Good
Soft crypto<---->soft crypto                    Good
Soft crypto<---->talitos                        link established but no traffic 
can pass through.

3. Looking at source code of latest stable kernel 3.8.2, I found that these two 
implementations don't agree on what's to be hashed in ESN case.
Talitos driver is more intuitive in that  "assoc (SPI, SN-hi, SN-low) + IV + 
payload" are hashed.
Kernel software crypto is counter-intuitive in that "hsg(SPI, SN-low) + sg(IV + 
payload) + tsg(SN-hi" are hashed.
I copy codelet from kernel 3.8.2 in the end.

Please let me know whether I read the code right. And which way is the right 
way.

Thanks

Chaoxing
 
Code from latest stable kernel 3.8.2

path: root/drivers/crypto/talitos.c

969: /* hmac data */
970:    desc->ptr[1].len = cpu_to_be16(areq->assoclen + ivsize);
        if (edesc->assoc_nents) {
                int tbl_off = edesc->src_nents + edesc->dst_nents + 2;
                struct talitos_ptr *tbl_ptr = &edesc->link_tbl[tbl_off];

                to_talitos_ptr(&desc->ptr[1], edesc->dma_link_tbl + tbl_off *
                               sizeof(struct talitos_ptr));
                desc->ptr[1].j_extent = DESC_PTR_LNKTBL_JUMP;

                /* assoc_nents - 1 entries for assoc, 1 for IV */
                sg_count = sg_to_link_tbl(areq->assoc, edesc->assoc_nents - 1,
                                          areq->assoclen, tbl_ptr);

                /* add IV to link table */
                tbl_ptr += sg_count - 1;
                tbl_ptr->j_extent = 0;
                tbl_ptr++;
                to_talitos_ptr(tbl_ptr, edesc->iv_dma);
                tbl_ptr->len = cpu_to_be16(ivsize);
                tbl_ptr->j_extent = DESC_PTR_LNKTBL_RETURN;

                dma_sync_single_for_device(dev, edesc->dma_link_tbl,
                                           edesc->dma_len, DMA_BIDIRECTIONAL);
        } else {
                to_talitos_ptr(&desc->ptr[1], sg_dma_address(areq->assoc));
                desc->ptr[1].j_extent = 0;
996:    }



path: root/crypto/authencesn.c

372:    err = crypto_ahash_init(ahreq);
373:    if (err)
                return ERR_PTR(err);

        ahash_request_set_crypt(ahreq, areq_ctx->hsg, hash, areq_ctx->headlen);
        ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
                                   areq_ctx->update_complete, req);

        err = crypto_ahash_update(ahreq);
        if (err)
                return ERR_PTR(err);

        ahash_request_set_crypt(ahreq, areq_ctx->sg, hash, areq_ctx->cryptlen);
        ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
                                   areq_ctx->update_complete2, req);

        err = crypto_ahash_update(ahreq);
        if (err)
                return ERR_PTR(err);

        ahash_request_set_crypt(ahreq, areq_ctx->tsg, hash,
                                areq_ctx->trailen);
        ahash_request_set_callback(ahreq, aead_request_flags(req) & flags,
                                   areq_ctx->complete, req);

397:    err = crypto_ahash_finup(ahreq);
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to