From: Gary R Hook <gary.hook@xxxxxxx>
AES GCM encryption allows for authsize values of 4, 8, and 12-16 bytes.
Validate the requested authsize, and retain it to save in the request
context.
Fixes: 36cf515b9bbe2 ("crypto: ccp - Enable support for AES GCM on v5 CCPs")
Signed-off-by: Gary R Hook <gary.hook@xxxxxxx>
---
drivers/crypto/ccp/ccp-crypto-aes-galois.c | 14 ++++++++++++
drivers/crypto/ccp/ccp-ops.c | 26 +++++++++++++++++-----
include/linux/ccp.h | 2 ++
3 files changed, 37 insertions(+), 5 deletions(-)
diff --git a/drivers/crypto/ccp/ccp-crypto-aes-galois.c b/drivers/crypto/ccp/ccp-crypto-aes-galois.c
index f9fec2ddf56a..94c1ad7eeddf 100644
--- a/drivers/crypto/ccp/ccp-crypto-aes-galois.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-galois.c
@@ -58,6 +58,19 @@ static int ccp_aes_gcm_setkey(struct crypto_aead *tfm, const u8 *key,
static int ccp_aes_gcm_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
+ switch (authsize) {
+ case 16:
+ case 15:
+ case 14:
+ case 13:
+ case 12:
+ case 8:
+ case 4:
+ break;
+ default:
+ return -EINVAL;
+ }
+
return 0;
}
@@ -104,6 +117,7 @@ static int ccp_aes_gcm_crypt(struct aead_request *req, bool encrypt)
memset(&rctx->cmd, 0, sizeof(rctx->cmd));
INIT_LIST_HEAD(&rctx->cmd.entry);
rctx->cmd.engine = CCP_ENGINE_AES;
+ rctx->cmd.u.aes.authsize = crypto_aead_authsize(tfm);
rctx->cmd.u.aes.type = ctx->u.aes.type;
rctx->cmd.u.aes.mode = ctx->u.aes.mode;
rctx->cmd.u.aes.action = encrypt;
diff --git a/drivers/crypto/ccp/ccp-ops.c b/drivers/crypto/ccp/ccp-ops.c
index 35b6b3397d49..553d8aa4f18d 100644
--- a/drivers/crypto/ccp/ccp-ops.c
+++ b/drivers/crypto/ccp/ccp-ops.c
@@ -621,6 +621,7 @@ ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
unsigned long long *final;
unsigned int dm_offset;
+ unsigned int authsize;
unsigned int jobid;
unsigned int ilen;
bool in_place = true; /* Default value */
@@ -642,6 +643,21 @@ ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
if (!aes->key) /* Gotta have a key SGL */
return -EINVAL;
+ /* Zero defaults to 16 bytes, the maximum size */
+ authsize = aes->authsize ? aes->authsize : AES_BLOCK_SIZE;
+ switch (authsize) {
+ case 16:
+ case 15:
+ case 14:
+ case 13:
+ case 12:
+ case 8:
+ case 4:
+ break;
+ default:
+ return -EINVAL;
+ }
+
/* First, decompose the source buffer into AAD & PT,
* and the destination buffer into AAD, CT & tag, or
* the input into CT & tag.
@@ -656,7 +672,7 @@ ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
p_tag = scatterwalk_ffwd(sg_tag, p_outp, ilen);
} else {
/* Input length for decryption includes tag */
- ilen = aes->src_len - AES_BLOCK_SIZE;
+ ilen = aes->src_len - authsize;
p_tag = scatterwalk_ffwd(sg_tag, p_inp, ilen);
}
@@ -838,19 +854,19 @@ ccp_run_aes_gcm_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd)
if (aes->action == CCP_AES_ACTION_ENCRYPT) {
/* Put the ciphered tag after the ciphertext. */
- ccp_get_dm_area(&final_wa, 0, p_tag, 0, AES_BLOCK_SIZE);
+ ccp_get_dm_area(&final_wa, 0, p_tag, 0, authsize);
} else {
/* Does this ciphered tag match the input? */
- ret = ccp_init_dm_workarea(&tag, cmd_q, AES_BLOCK_SIZE,
+ ret = ccp_init_dm_workarea(&tag, cmd_q, authsize,
DMA_BIDIRECTIONAL);
if (ret)
goto e_tag;
- ret = ccp_set_dm_area(&tag, 0, p_tag, 0, AES_BLOCK_SIZE);
+ ret = ccp_set_dm_area(&tag, 0, p_tag, 0, authsize);
if (ret)
goto e_tag;
ret = crypto_memneq(tag.address, final_wa.address,
- AES_BLOCK_SIZE) ? -EBADMSG : 0;
+ authsize) ? -EBADMSG : 0;
ccp_dm_free(&tag);
}
diff --git a/include/linux/ccp.h b/include/linux/ccp.h
index 55cb455cfcb0..a5dfbaf2470d 100644
--- a/include/linux/ccp.h
+++ b/include/linux/ccp.h
@@ -170,6 +170,8 @@ struct ccp_aes_engine {
enum ccp_aes_mode mode;
enum ccp_aes_action action;
+ u32 authsize;
+
struct scatterlist *key;
u32 key_len; /* In bytes */
--
2.17.1
