[PATCH 05/10] crypto: nx - fix limits to sg lists for AES-GCM
Marcelo Cerri
mhcerri at linux.vnet.ibm.com
Sat Aug 24 06:01:09 EST 2013
This patch updates the nx-aes-gcm implementation to perform several
hyper calls if needed in order to always respect the length limits for
scatter/gather lists.
Two different limits are considered:
- "ibm,max-sg-len": maximum number of bytes of each scatter/gather
list.
- "ibm,max-sync-cop":
- The total number of bytes that a scatter/gather list can hold.
- The maximum number of elements that a scatter/gather list can have.
Reviewed-by: Joy Latten <jmlatten at linux.vnet.ibm.com>
Signed-off-by: Marcelo Cerri <mhcerri at linux.vnet.ibm.com>
---
drivers/crypto/nx/nx-aes-gcm.c | 202 +++++++++++++++++++++++++++--------------
1 file changed, 136 insertions(+), 66 deletions(-)
diff --git a/drivers/crypto/nx/nx-aes-gcm.c b/drivers/crypto/nx/nx-aes-gcm.c
index c2d6f76..9e89bdf 100644
--- a/drivers/crypto/nx/nx-aes-gcm.c
+++ b/drivers/crypto/nx/nx-aes-gcm.c
@@ -125,37 +125,101 @@ static int nx_gca(struct nx_crypto_ctx *nx_ctx,
struct aead_request *req,
u8 *out)
{
+ int rc;
struct nx_csbcpb *csbcpb_aead = nx_ctx->csbcpb_aead;
- int rc = -EINVAL;
struct scatter_walk walk;
struct nx_sg *nx_sg = nx_ctx->in_sg;
+ unsigned int nbytes = req->assoclen;
+ unsigned int processed = 0, to_process;
+ u32 max_sg_len;
- if (req->assoclen > nx_ctx->ap->databytelen)
- goto out;
-
- if (req->assoclen <= AES_BLOCK_SIZE) {
+ if (nbytes <= AES_BLOCK_SIZE) {
scatterwalk_start(&walk, req->assoc);
- scatterwalk_copychunks(out, &walk, req->assoclen,
- SCATTERWALK_FROM_SG);
+ scatterwalk_copychunks(out, &walk, nbytes, SCATTERWALK_FROM_SG);
scatterwalk_done(&walk, SCATTERWALK_FROM_SG, 0);
-
- rc = 0;
- goto out;
+ return 0;
}
- nx_sg = nx_walk_and_build(nx_sg, nx_ctx->ap->sglen, req->assoc, 0,
- req->assoclen);
- nx_ctx->op_aead.inlen = (nx_ctx->in_sg - nx_sg) * sizeof(struct nx_sg);
+ NX_CPB_FDM(csbcpb_aead) &= ~NX_FDM_CONTINUATION;
- rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
- req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
- if (rc)
- goto out;
+ /* 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);
- atomic_inc(&(nx_ctx->stats->aes_ops));
- atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));
+ 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_aead) |= NX_FDM_INTERMEDIATE;
+ else
+ NX_CPB_FDM(csbcpb_aead) &= ~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_aead.inlen = (nx_ctx->in_sg - nx_sg)
+ * sizeof(struct nx_sg);
+
+ rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
+ req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
+ if (rc)
+ return rc;
+
+ memcpy(csbcpb_aead->cpb.aes_gca.in_pat,
+ csbcpb_aead->cpb.aes_gca.out_pat,
+ AES_BLOCK_SIZE);
+ NX_CPB_FDM(csbcpb_aead) |= 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);
memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE);
+
+ 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;
+
+ /* 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);
+ if (enc)
+ rc = crypto_blkcipher_encrypt_iv(desc, req->dst, &sg,
+ AES_BLOCK_SIZE);
+ else
+ rc = crypto_blkcipher_decrypt_iv(desc, req->dst, &sg,
+ AES_BLOCK_SIZE);
+ crypto_free_blkcipher(desc->tfm);
+
out:
return rc;
}
@@ -166,79 +230,85 @@ static int gcm_aes_nx_crypt(struct aead_request *req, int enc)
struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
struct blkcipher_desc desc;
unsigned int nbytes = req->cryptlen;
+ unsigned int processed = 0, to_process;
unsigned long irq_flags;
+ u32 max_sg_len;
int rc = -EINVAL;
spin_lock_irqsave(&nx_ctx->lock, irq_flags);
- if (nbytes > nx_ctx->ap->databytelen)
- goto out;
-
desc.info = nx_ctx->priv.gcm.iv;
/* initialize the counter */
*(u32 *)(desc.info + NX_GCM_CTR_OFFSET) = 1;
- /* 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 */
if (nbytes == 0) {
- 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);
- if (enc)
- crypto_blkcipher_encrypt_iv(&desc, req->dst, &sg,
- AES_BLOCK_SIZE);
- else
- crypto_blkcipher_decrypt_iv(&desc, req->dst, &sg,
- AES_BLOCK_SIZE);
- crypto_free_blkcipher(desc.tfm);
-
- rc = 0;
+ rc = gcm_empty(req, &desc, enc);
goto out;
}
- desc.tfm = (struct crypto_blkcipher *)req->base.tfm;
-
+ /* Process associated data */
csbcpb->cpb.aes_gcm.bit_length_aad = req->assoclen * 8;
-
if (req->assoclen) {
rc = nx_gca(nx_ctx, req, csbcpb->cpb.aes_gcm.in_pat_or_aad);
if (rc)
goto out;
}
- if (enc)
+ /* Set flags for encryption */
+ NX_CPB_FDM(csbcpb) &= ~NX_FDM_CONTINUATION;
+ if (enc) {
NX_CPB_FDM(csbcpb) |= NX_FDM_ENDE_ENCRYPT;
- else
+ } else {
+ NX_CPB_FDM(csbcpb) &= ~NX_FDM_ENDE_ENCRYPT;
nbytes -= crypto_aead_authsize(crypto_aead_reqtfm(req));
+ }
- csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8;
+ /* 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);
- rc = nx_build_sg_lists(nx_ctx, &desc, req->dst, req->src, nbytes, 0,
- csbcpb->cpb.aes_gcm.iv_or_cnt);
- if (rc)
- goto out;
+ 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));
- rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
- req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
- if (rc)
- goto out;
+ if ((to_process + processed) < nbytes)
+ NX_CPB_FDM(csbcpb) |= NX_FDM_INTERMEDIATE;
+ else
+ NX_CPB_FDM(csbcpb) &= ~NX_FDM_INTERMEDIATE;
- atomic_inc(&(nx_ctx->stats->aes_ops));
- atomic64_add(csbcpb->csb.processed_byte_count,
- &(nx_ctx->stats->aes_bytes));
+ csbcpb->cpb.aes_gcm.bit_length_data = nbytes * 8;
+ desc.tfm = (struct crypto_blkcipher *) req->base.tfm;
+ rc = nx_build_sg_lists(nx_ctx, &desc, req->dst,
+ req->src, to_process, processed,
+ csbcpb->cpb.aes_gcm.iv_or_cnt);
+ if (rc)
+ goto out;
+
+ rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
+ req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
+ if (rc)
+ goto out;
+
+ memcpy(desc.info, csbcpb->cpb.aes_gcm.out_cnt, AES_BLOCK_SIZE);
+ 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(csbcpb->csb.processed_byte_count,
+ &(nx_ctx->stats->aes_bytes));
+
+ processed += to_process;
+ } while (processed < nbytes);
if (enc) {
/* copy out the auth tag */
--
1.7.12
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