crypto: nx - fix limits to sg lists for AES-GCM

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@linux.vnet.ibm.com>
Signed-off-by: Marcelo Cerri <mhcerri@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Marcelo Cerri 2013-08-29 11:36:35 -03:00 committed by Herbert Xu
parent 884d981b04
commit 799804348d

View file

@ -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);
return 0;
}
rc = 0;
NX_CPB_FDM(csbcpb_aead) &= ~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);
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;
}
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);
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);
rc = nx_hcall_sync(nx_ctx, &nx_ctx->op_aead,
req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
if (rc)
goto out;
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);
atomic_inc(&(nx_ctx->stats->aes_ops));
atomic64_add(req->assoclen, &(nx_ctx->stats->aes_bytes));
memcpy(out, csbcpb_aead->cpb.aes_gca.out_pat, AES_BLOCK_SIZE);
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 */