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

From: Iuliana Prodan
Date: Thu Jul 18 2019 - 10:46:07 EST


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 <iuliana.prodan@xxxxxxx>
---
drivers/crypto/caam/caamalg_desc.c | 46 +++++++++++++++++++++++++-------------
drivers/crypto/caam/caamalg_desc.h | 2 +-
2 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/drivers/crypto/caam/caamalg_desc.c b/drivers/crypto/caam/caamalg_desc.c
index 7253183..99f419a 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 */
@@ -890,26 +893,25 @@ 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);
+ append_math_add(desc, VARSEQOUTLEN, REG0, REG3, CAAM_CMD_SZ);

- /* Read assoc data */
+ /* Skip AAD */
+ append_seq_fifo_store(desc, 0, FIFOST_TYPE_SKIP | FIFOLDST_VLF);
+
+ /* Read cryptlen and set this value into VARSEQOUTLEN */
+ append_math_sub(desc, VARSEQOUTLEN, SEQINLEN, REG3, 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);
+
+ /* Read AAD data */
append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLDST_VLF |
FIFOLD_TYPE_AAD | FIFOLD_TYPE_FLUSH1);

/* Skip IV */
append_seq_fifo_load(desc, ivsize, FIFOLD_CLASS_SKIP);
-
- /* Will read cryptlen bytes */
- append_math_sub(desc, VARSEQINLEN, SEQINLEN, REG0, CAAM_CMD_SZ);
-
- /* Workaround for erratum A-005473 (simultaneous SEQ FIFO skips) */
- append_seq_fifo_load(desc, 0, FIFOLD_CLASS_CLASS1 | FIFOLD_TYPE_MSG);
-
- /* Skip assoc data */
- append_seq_fifo_store(desc, 0, FIFOST_TYPE_SKIP | FIFOLDST_VLF);
-
- /* cryptlen = seqoutlen - assoclen */
- append_math_sub(desc, VARSEQOUTLEN, VARSEQINLEN, REG0, CAAM_CMD_SZ);
+ 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 +920,18 @@ 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..a49fb53 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 + 15 * 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