crypto: nx - fix GCM for zero length messages
[firefly-linux-kernel-4.4.55.git] / drivers / crypto / nx / nx-aes-gcm.c
index 9e89bdf344877b8b589d66e64e041bbb88f091bb..025d9a8d5b1908126804c8468d30ec6902cb4c59 100644 (file)
@@ -187,40 +187,125 @@ static int nx_gca(struct nx_crypto_ctx  *nx_ctx,
        return rc;
 }
 
+static int gmac(struct aead_request *req, struct blkcipher_desc *desc)
+{
+       int rc;
+       struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
+       struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
+       struct nx_sg *nx_sg;
+       unsigned int nbytes = req->assoclen;
+       unsigned int processed = 0, to_process;
+       u32 max_sg_len;
+
+       /* Set GMAC mode */
+       csbcpb->cpb.hdr.mode = NX_MODE_AES_GMAC;
+
+       NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
+
+       /* page_limit: number of sg entries that fit on one page */
+       max_sg_len = min_t(u32, nx_driver.of.max_sg_len/sizeof(struct nx_sg),
+                          nx_ctx->ap->sglen);
+
+       /* Copy IV */
+       memcpy(csbcpb->cpb.aes_gcm.iv_or_cnt, desc->info, AES_BLOCK_SIZE);
+
+       do {
+               /*
+                * to_process: the data chunk to process in this update.
+                * This value is bound by sg list limits.
+                */
+               to_process = min_t(u64, nbytes - processed,
+                                  nx_ctx->ap->databytelen);
+               to_process = min_t(u64, to_process,
+                                  NX_PAGE_SIZE * (max_sg_len - 1));
+
+               if ((to_process + processed) < nbytes)
+                       NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
+               else
+                       NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
+
+               nx_sg = nx_walk_and_build(nx_ctx->in_sg, nx_ctx->ap->sglen,
+                                         req->assoc, processed, to_process);
+               nx_ctx->op.inlen = (nx_ctx->in_sg - nx_sg)
+                                       * sizeof(struct nx_sg);
+
+               csbcpb->cpb.aes_gcm.bit_length_data = 0;
+               csbcpb->cpb.aes_gcm.bit_length_aad = 8 * nbytes;
+
+               rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
+                               req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
+               if (rc)
+                       goto out;
+
+               memcpy(csbcpb->cpb.aes_gcm.in_pat_or_aad,
+                       csbcpb->cpb.aes_gcm.out_pat_or_mac, AES_BLOCK_SIZE);
+               memcpy(csbcpb->cpb.aes_gcm.in_s0,
+                       csbcpb->cpb.aes_gcm.out_s0, AES_BLOCK_SIZE);
+
+               NX_CPB_FDM(csbcpb) |= NX_FDM_CONTINUATION;
+
+               atomic_inc(&(nx_ctx->stats->aes_ops));
+               atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));
+
+               processed += to_process;
+       } while (processed < nbytes);
+
+out:
+       /* Restore GCM mode */
+       csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM;
+       return rc;
+}
+
 static int gcm_empty(struct aead_request *req, struct blkcipher_desc *desc,
                     int enc)
 {
        int rc;
        struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
+       char out[AES_BLOCK_SIZE];
+       struct nx_sg *in_sg, *out_sg;
 
        /* For scenarios where the input message is zero length, AES CTR mode
         * may be used. Set the source data to be a single block (16B) of all
         * zeros, and set the input IV value to be the same as the GMAC IV
         * value. - nx_wb 4.8.1.3 */
-       char src[AES_BLOCK_SIZE] = {};
-       struct scatterlist sg;
-
-       desc->tfm = crypto_alloc_blkcipher("ctr(aes)", 0, 0);
-       if (IS_ERR(desc->tfm)) {
-               rc = -ENOMEM;
-               goto out;
-       }
-
-       crypto_blkcipher_setkey(desc->tfm, csbcpb->cpb.aes_gcm.key,
-               NX_CPB_KEY_SIZE(csbcpb) == NX_KS_AES_128 ? 16 :
-               NX_CPB_KEY_SIZE(csbcpb) == NX_KS_AES_192 ? 24 : 32);
 
-       sg_init_one(&sg, src, AES_BLOCK_SIZE);
+       /* Change to ECB mode */
+       csbcpb->cpb.hdr.mode = NX_MODE_AES_ECB;
+       memcpy(csbcpb->cpb.aes_ecb.key, csbcpb->cpb.aes_gcm.key,
+                       sizeof(csbcpb->cpb.aes_ecb.key));
        if (enc)
-               rc = crypto_blkcipher_encrypt_iv(desc, req->dst, &sg,
-                                                AES_BLOCK_SIZE);
+               NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
        else
-               rc = crypto_blkcipher_decrypt_iv(desc, req->dst, &sg,
-                                                AES_BLOCK_SIZE);
-       crypto_free_blkcipher(desc->tfm);
+               NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
+
+       /* Encrypt the counter/IV */
+       in_sg = nx_build_sg_list(nx_ctx->in_sg, (u8 *) desc->info,
+                                AES_BLOCK_SIZE, nx_ctx->ap->sglen);
+       out_sg = nx_build_sg_list(nx_ctx->out_sg, (u8 *) out, sizeof(out),
+                                 nx_ctx->ap->sglen);
+       nx_ctx->op.inlen = (nx_ctx->in_sg - in_sg) * sizeof(struct nx_sg);
+       nx_ctx->op.outlen = (nx_ctx->out_sg - out_sg) * sizeof(struct nx_sg);
 
+       rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
+                          desc->flags & CRYPTO_TFM_REQ_MAY_SLEEP);
+       if (rc)
+               goto out;
+       atomic_inc(&(nx_ctx->stats->aes_ops));
+
+       /* Copy out the auth tag */
+       memcpy(csbcpb->cpb.aes_gcm.out_pat_or_mac, out,
+                       crypto_aead_authsize(crypto_aead_reqtfm(req)));
 out:
+       /* Restore XCBC mode */
+       csbcpb->cpb.hdr.mode = NX_MODE_AES_GCM;
+
+       /*
+        * ECB key uses the same region that GCM AAD and counter, so it's safe
+        * to just fill it with zeroes.
+        */
+       memset(csbcpb->cpb.aes_ecb.key, 0, sizeof(csbcpb->cpb.aes_ecb.key));
+
        return rc;
 }
 
@@ -242,8 +327,14 @@ static int gcm_aes_nx_crypt(struct aead_request *req, int enc)
        *(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1;
 
        if (nbytes == 0) {
-               rc = gcm_empty(req, &desc, enc);
-               goto out;
+               if (req->assoclen == 0)
+                       rc = gcm_empty(req, &desc, enc);
+               else
+                       rc = gmac(req, &desc);
+               if (rc)
+                       goto out;
+               else
+                       goto mac;
        }
 
        /* Process associated data */
@@ -310,6 +401,7 @@ static int gcm_aes_nx_crypt(struct aead_request *req, int enc)
                processed += to_process;
        } while (processed < nbytes);
 
+mac:
        if (enc) {
                /* copy out the auth tag */
                scatterwalk_map_and_copy(csbcpb->cpb.aes_gcm.out_pat_or_mac,