2019-07-30 12:10:06

by Iuliana Prodan

[permalink] [raw]
Subject: [PATCH v4 08/14] crypto: caam - update rfc4106 sh desc to support zero length input

Update share descriptor for rfc4106 to skip instructions in case
cryptlen is zero. If no instructions are jumped the DECO hangs and a
timeout error is thrown.

Signed-off-by: Iuliana Prodan <[email protected]>
---
Changes since v3:
- move the erratum workaround to reduce the chances of DECO stalling.
---
drivers/crypto/caam/caamalg_desc.c | 47 ++++++++++++++++++++++++++------------
drivers/crypto/caam/caamalg_desc.h | 2 +-
2 files changed, 33 insertions(+), 16 deletions(-)

diff --git a/drivers/crypto/caam/caamalg_desc.c b/drivers/crypto/caam/caamalg_desc.c
index 7253183..5ddaf61 100644
--- a/drivers/crypto/caam/caamalg_desc.c
+++ b/drivers/crypto/caam/caamalg_desc.c
@@ -843,13 +843,16 @@ EXPORT_SYMBOL(cnstr_shdsc_gcm_decap);
* @ivsize: initialization vector size
* @icvsize: integrity check value (ICV) size (truncated or full)
* @is_qi: true when called from caam/qi
+ *
+ * Input sequence: AAD | PTXT
+ * Output sequence: AAD | CTXT | ICV
+ * AAD length (assoclen), which includes the IV length, is available in Math3.
*/
void cnstr_shdsc_rfc4106_encap(u32 * const desc, struct alginfo *cdata,
unsigned int ivsize, unsigned int icvsize,
const bool is_qi)
{
- u32 *key_jump_cmd;
-
+ u32 *key_jump_cmd, *zero_cryptlen_jump_cmd, *skip_instructions;
init_sh_desc(desc, HDR_SHARE_SERIAL);

/* Skip key loading if it is loaded due to sharing */
@@ -892,24 +895,26 @@ void cnstr_shdsc_rfc4106_encap(u32 * const desc, struct alginfo *cdata,
append_math_sub_imm_u32(desc, VARSEQINLEN, REG3, IMM, ivsize);
append_math_add(desc, VARSEQOUTLEN, ZERO, REG3, CAAM_CMD_SZ);

- /* Read assoc data */
- append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLDST_VLF |
- FIFOLD_TYPE_AAD | FIFOLD_TYPE_FLUSH1);
+ /* Skip AAD */
+ append_seq_fifo_store(desc, 0, FIFOST_TYPE_SKIP | FIFOLDST_VLF);

- /* Skip IV */
- append_seq_fifo_load(desc, ivsize, FIFOLD_CLASS_SKIP);
+ /* Read cryptlen and set this value into VARSEQOUTLEN */
+ append_math_sub(desc, VARSEQOUTLEN, SEQINLEN, REG3, CAAM_CMD_SZ);

- /* Will read cryptlen bytes */
- append_math_sub(desc, VARSEQINLEN, SEQINLEN, REG0, CAAM_CMD_SZ);
+ /* If cryptlen is ZERO jump to AAD command */
+ zero_cryptlen_jump_cmd = append_jump(desc, JUMP_TEST_ALL |
+ JUMP_COND_MATH_Z);

- /* Workaround for erratum A-005473 (simultaneous SEQ FIFO skips) */
- append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLD_TYPE_MSG);
+ /* Read AAD data */
+ append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLDST_VLF |
+ FIFOLD_TYPE_AAD | FIFOLD_TYPE_FLUSH1);

- /* Skip assoc data */
- append_seq_fifo_store(desc, 0, FIFOST_TYPE_SKIP | FIFOLDST_VLF);
+ /* Workaround for erratum A-005473 (simultaneous SEQ FIFO skips) */
+ append_seq_fifo_store(desc, 0, FIFOST_TYPE_MESSAGE_DATA);

- /* cryptlen = seqoutlen - assoclen */
- append_math_sub(desc, VARSEQOUTLEN, VARSEQINLEN, REG0, CAAM_CMD_SZ);
+ /* Skip IV */
+ append_seq_fifo_load(desc, ivsize, FIFOLD_CLASS_SKIP);
+ append_math_add(desc, VARSEQINLEN, VARSEQOUTLEN, REG0, CAAM_CMD_SZ);

/* Write encrypted data */
append_seq_fifo_store(desc, 0, FIFOST_TYPE_MESSAGE_DATA | FIFOLDST_VLF);
@@ -918,6 +923,18 @@ void cnstr_shdsc_rfc4106_encap(u32 * const desc, struct alginfo *cdata,
append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLDST_VLF |
FIFOLD_TYPE_MSG | FIFOLD_TYPE_LAST1);

+ /* Jump instructions to avoid double reading of AAD */
+ skip_instructions = append_jump(desc, JUMP_TEST_ALL);
+
+ /* There is no input data, cryptlen = 0 */
+ set_jump_tgt_here(desc, zero_cryptlen_jump_cmd);
+
+ /* Read AAD */
+ append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLDST_VLF |
+ FIFOLD_TYPE_AAD | FIFOLD_TYPE_LAST1);
+
+ set_jump_tgt_here(desc, skip_instructions);
+
/* Write ICV */
append_seq_store(desc, icvsize, LDST_CLASS_1_CCB |
LDST_SRCDST_BYTE_CONTEXT);
diff --git a/drivers/crypto/caam/caamalg_desc.h b/drivers/crypto/caam/caamalg_desc.h
index da4a4ee..a6146ea 100644
--- a/drivers/crypto/caam/caamalg_desc.h
+++ b/drivers/crypto/caam/caamalg_desc.h
@@ -31,7 +31,7 @@
#define DESC_QI_GCM_DEC_LEN (DESC_GCM_DEC_LEN + 3 * CAAM_CMD_SZ)

#define DESC_RFC4106_BASE (3 * CAAM_CMD_SZ)
-#define DESC_RFC4106_ENC_LEN (DESC_RFC4106_BASE + 13 * CAAM_CMD_SZ)
+#define DESC_RFC4106_ENC_LEN (DESC_RFC4106_BASE + 16 * CAAM_CMD_SZ)
#define DESC_RFC4106_DEC_LEN (DESC_RFC4106_BASE + 13 * CAAM_CMD_SZ)
#define DESC_QI_RFC4106_ENC_LEN (DESC_RFC4106_ENC_LEN + 5 * CAAM_CMD_SZ)
#define DESC_QI_RFC4106_DEC_LEN (DESC_RFC4106_DEC_LEN + 5 * CAAM_CMD_SZ)
--
2.1.0