Make the Aspeed HACE module use the new qcrypto accumulative hashing functions
when in scatter-gather accumulative mode. A hash context will maintain a
"running-hash" as each scatter-gather chunk is received.
Previously each scatter-gather "chunk" was cached
so the hash could be computed once the final chunk was received.
However, the cache was a shallow copy, so once the guest overwrote the
memory provided to HACE the final hash would not be correct.
Possibly related to: https://gitlab.com/qemu-project/qemu/-/issues/1121
Buglink: https://github.com/openbmc/qemu/issues/36
Signed-off-by: Alejandro Zeise <alejandro.zeise@seagate.com>
---
hw/misc/aspeed_hace.c | 92 ++++++++++++++++++-----------------
include/hw/misc/aspeed_hace.h | 4 ++
2 files changed, 52 insertions(+), 44 deletions(-)
diff --git a/hw/misc/aspeed_hace.c b/hw/misc/aspeed_hace.c
index c06c04ddc6..5077204ee6 100644
--- a/hw/misc/aspeed_hace.c
+++ b/hw/misc/aspeed_hace.c
@@ -1,6 +1,7 @@
/*
* ASPEED Hash and Crypto Engine
*
+ * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
* Copyright (C) 2021 IBM Corp.
*
* Joel Stanley <joel@jms.id.au>
@@ -151,50 +152,28 @@ static int reconstruct_iov(AspeedHACEState *s, struct iovec *iov, int id,
return iov_count;
}
-/**
- * Generate iov for accumulative mode.
- *
- * @param s aspeed hace state object
- * @param iov iov of the current request
- * @param id index of the current iov
- * @param req_len length of the current request
- *
- * @return count of iov
- */
-static int gen_acc_mode_iov(AspeedHACEState *s, struct iovec *iov, int id,
- hwaddr *req_len)
-{
- uint32_t pad_offset;
- uint32_t total_msg_len;
- s->total_req_len += *req_len;
-
- if (has_padding(s, &iov[id], *req_len, &total_msg_len, &pad_offset)) {
- if (s->iov_count) {
- return reconstruct_iov(s, iov, id, &pad_offset);
- }
-
- *req_len -= s->total_req_len - total_msg_len;
- s->total_req_len = 0;
- iov[id].iov_len = *req_len;
- } else {
- s->iov_cache[s->iov_count].iov_base = iov->iov_base;
- s->iov_cache[s->iov_count].iov_len = *req_len;
- ++s->iov_count;
- }
-
- return id + 1;
-}
-
static void do_hash_operation(AspeedHACEState *s, int algo, bool sg_mode,
bool acc_mode)
{
struct iovec iov[ASPEED_HACE_MAX_SG];
+ uint32_t total_msg_len;
+ uint32_t pad_offset;
g_autofree uint8_t *digest_buf = NULL;
size_t digest_len = 0;
- int niov = 0;
+ bool sg_acc_mode_final_request = false;
int i;
void *haddr;
+ if (acc_mode && s->hash_ctx == NULL) {
+ s->hash_ctx = qcrypto_hash_new(algo, NULL);
+ if (s->hash_ctx == NULL) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: qcrypto failed to create hash context\n",
+ __func__);
+ return;
+ }
+ }
+
if (sg_mode) {
uint32_t len = 0;
@@ -226,8 +203,15 @@ static void do_hash_operation(AspeedHACEState *s, int algo, bool sg_mode,
}
iov[i].iov_base = haddr;
if (acc_mode) {
- niov = gen_acc_mode_iov(s, iov, i, &plen);
-
+ s->total_req_len += plen;
+
+ if (has_padding(s, &iov[i], plen, &total_msg_len, &pad_offset)) {
+ /* Padding being present indicates the final request */
+ sg_acc_mode_final_request = true;
+ iov[i].iov_len = pad_offset;
+ } else {
+ iov[i].iov_len = plen;
+ }
} else {
iov[i].iov_len = plen;
}
@@ -252,20 +236,38 @@ static void do_hash_operation(AspeedHACEState *s, int algo, bool sg_mode,
* required to check whether cache is empty. If no, we should
* combine cached iov and the current iov.
*/
- uint32_t total_msg_len;
- uint32_t pad_offset;
s->total_req_len += len;
if (has_padding(s, iov, len, &total_msg_len, &pad_offset)) {
- niov = reconstruct_iov(s, iov, 0, &pad_offset);
+ i = reconstruct_iov(s, iov, 0, &pad_offset);
}
}
}
- if (niov) {
- i = niov;
- }
+ if (acc_mode) {
+ if (qcrypto_hash_update(s->hash_ctx, iov, i, NULL) < 0) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: qcrypto hash update failed\n", __func__);
+ return;
+ }
+
+ if (sg_acc_mode_final_request) {
+ if (qcrypto_hash_finalize_bytes(s->hash_ctx, &digest_buf,
+ &digest_len, NULL)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: qcrypto failed to finalize hash\n", __func__);
+ }
- if (qcrypto_hash_bytesv(algo, iov, i, &digest_buf, &digest_len, NULL) < 0) {
+ if (qcrypto_hash_free(s->hash_ctx)) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: qcrypto failed to free context\n", __func__);
+ }
+
+ s->hash_ctx = NULL;
+ s->iov_count = 0;
+ s->total_req_len = 0;
+ }
+ } else if (qcrypto_hash_bytesv(algo, iov, i, &digest_buf,
+ &digest_len, NULL) < 0) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: qcrypto failed\n", __func__);
return;
}
@@ -397,6 +396,11 @@ static void aspeed_hace_reset(DeviceState *dev)
{
struct AspeedHACEState *s = ASPEED_HACE(dev);
+ if (s->hash_ctx != NULL) {
+ qcrypto_hash_free(s->hash_ctx);
+ s->hash_ctx = NULL;
+ }
+
memset(s->regs, 0, sizeof(s->regs));
s->iov_count = 0;
s->total_req_len = 0;
diff --git a/include/hw/misc/aspeed_hace.h b/include/hw/misc/aspeed_hace.h
index ecb1b67de8..4af9919195 100644
--- a/include/hw/misc/aspeed_hace.h
+++ b/include/hw/misc/aspeed_hace.h
@@ -1,6 +1,7 @@
/*
* ASPEED Hash and Crypto Engine
*
+ * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
* Copyright (C) 2021 IBM Corp.
*
* SPDX-License-Identifier: GPL-2.0-or-later
@@ -10,6 +11,7 @@
#define ASPEED_HACE_H
#include "hw/sysbus.h"
+#include "crypto/hash.h"
#define TYPE_ASPEED_HACE "aspeed.hace"
#define TYPE_ASPEED_AST2400_HACE TYPE_ASPEED_HACE "-ast2400"
@@ -35,6 +37,8 @@ struct AspeedHACEState {
MemoryRegion *dram_mr;
AddressSpace dram_as;
+
+ QCryptoHash *hash_ctx;
};
--
2.34.1