feat(rmmd): el3 token sign during attestation
Add required SMCs by RMM to push attestation signing requests to EL3
and get responses. EL3 may then choose to push these requests to a HES
as suitable for a platform. This patch also supports the new
RMM_EL3_FEATURES interface, that RMM can use to query for support for
HES based signing. The new interface exposes a feature register with
different bits defining different discoverable features. This new
interface is available starting the 0.4 version of the RMM-EL3
interface, causing the version to bump up. This patch also adds a
platform port for FVP that implements the platform hooks required to
enable the new SMCs, but it does not push to a HES and instead copies a
zeroed buffer in EL3.
Change-Id: I69c110252835122a9533e71bdcce10b5f2a686b2
Signed-off-by: Raghu Krishnamurthy <raghupathyk@nvidia.com>
diff --git a/services/std_svc/rmmd/rmmd_attest.c b/services/std_svc/rmmd/rmmd_attest.c
index f73236c..7d4ea70 100644
--- a/services/std_svc/rmmd/rmmd_attest.c
+++ b/services/std_svc/rmmd/rmmd_attest.c
@@ -1,5 +1,6 @@
/*
* Copyright (c) 2022-2024, Arm Limited. All rights reserved.
+ * Copyright (c) 2024, NVIDIA Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -12,7 +13,8 @@
#include <lib/xlat_tables/xlat_tables_v2.h>
#include <plat/common/platform.h>
#include "rmmd_private.h"
-#include <services/rmmd_svc.h>
+#include <services/rmm_el3_token_sign.h>
+#include <smccc_helpers.h>
static spinlock_t lock;
@@ -156,10 +158,110 @@
(unsigned int)ecc_curve);
if (err != 0) {
ERROR("Failed to get attestation key: %d.\n", err);
- err = E_RMM_UNK;
+ err = E_RMM_UNK;
}
spin_unlock(&lock);
return err;
}
+
+static int rmmd_el3_token_sign_push_req(uint64_t buf_pa, uint64_t buf_size)
+{
+ int err;
+
+ err = validate_buffer_params(buf_pa, buf_size);
+ if (err != 0) {
+ return err;
+ }
+
+ if (buf_size < sizeof(struct el3_token_sign_request)) {
+ return E_RMM_INVAL;
+ }
+
+ spin_lock(&lock);
+
+ /* Call platform port to handle attestation toekn signing request. */
+ err = plat_rmmd_el3_token_sign_push_req((struct el3_token_sign_request *)buf_pa);
+
+ spin_unlock(&lock);
+
+ return err;
+}
+
+static int rmmd_el3_token_sign_pull_resp(uint64_t buf_pa, uint64_t buf_size)
+{
+ int err;
+
+ err = validate_buffer_params(buf_pa, buf_size);
+ if (err != 0) {
+ return err;
+ }
+
+
+ if (buf_size < sizeof(struct el3_token_sign_response)) {
+ return E_RMM_INVAL;
+ }
+
+ spin_lock(&lock);
+
+ /* Pull attestation signing response from HES. */
+ err = plat_rmmd_el3_token_sign_pull_resp(
+ (struct el3_token_sign_response *)buf_pa);
+
+ spin_unlock(&lock);
+
+ return err;
+}
+
+static int rmmd_attest_get_attest_pub_key(uint64_t buf_pa, uint64_t *buf_size,
+ uint64_t ecc_curve)
+{
+ int err;
+
+ err = validate_buffer_params(buf_pa, *buf_size);
+ if (err != 0) {
+ return err;
+ }
+
+ if (ecc_curve != ATTEST_KEY_CURVE_ECC_SECP384R1) {
+ ERROR("Invalid ECC curve specified\n");
+ return E_RMM_INVAL;
+ }
+
+ spin_lock(&lock);
+
+ /* Get the Realm attestation public key from platform port. */
+ err = plat_rmmd_el3_token_sign_get_rak_pub(
+ (uintptr_t)buf_pa, buf_size, (unsigned int)ecc_curve);
+
+ spin_unlock(&lock);
+ if (err != 0) {
+ ERROR("Failed to get attestation public key from HES: %d.\n",
+ err);
+ err = E_RMM_UNK;
+ }
+
+
+ return err;
+}
+
+uint64_t rmmd_el3_token_sign(void *handle, uint64_t opcode, uint64_t x2,
+ uint64_t x3, uint64_t x4)
+{
+ int ret;
+
+ switch (opcode) {
+ case RMM_EL3_TOKEN_SIGN_PUSH_REQ_OP:
+ ret = rmmd_el3_token_sign_push_req(x2, x3);
+ SMC_RET1(handle, ret);
+ case RMM_EL3_TOKEN_SIGN_PULL_RESP_OP:
+ ret = rmmd_el3_token_sign_pull_resp(x2, x3);
+ SMC_RET1(handle, ret);
+ case RMM_EL3_TOKEN_SIGN_GET_RAK_PUB_OP:
+ ret = rmmd_attest_get_attest_pub_key(x2, &x3, x4);
+ SMC_RET2(handle, ret, x3);
+ default:
+ SMC_RET1(handle, SMC_UNK);
+ }
+}
diff --git a/services/std_svc/rmmd/rmmd_main.c b/services/std_svc/rmmd/rmmd_main.c
index 153bb01..d063ea3 100644
--- a/services/std_svc/rmmd/rmmd_main.c
+++ b/services/std_svc/rmmd/rmmd_main.c
@@ -441,6 +441,21 @@
return ret;
}
+static int rmm_el3_ifc_get_feat_register(uint64_t feat_reg_idx,
+ uint64_t *feat_reg)
+{
+ if (feat_reg_idx != RMM_EL3_FEAT_REG_0_IDX) {
+ ERROR("RMMD: Failed to get feature register %ld\n", feat_reg_idx);
+ return E_RMM_INVAL;
+ }
+
+ *feat_reg = 0UL;
+#if RMMD_ENABLE_EL3_TOKEN_SIGN
+ *feat_reg |= RMM_EL3_FEAT_REG_0_EL3_TOKEN_SIGN_MASK;
+#endif
+ return E_RMM_OK;
+}
+
/*******************************************************************************
* This function handles RMM-EL3 interface SMCs
******************************************************************************/
@@ -448,7 +463,7 @@
uint64_t x3, uint64_t x4, void *cookie,
void *handle, uint64_t flags)
{
- uint64_t remaining_len = 0;
+ uint64_t remaining_len = 0UL;
uint32_t src_sec_state;
int ret;
@@ -479,7 +494,13 @@
case RMM_ATTEST_GET_REALM_KEY:
ret = rmmd_attest_get_signing_key(x1, &x2, x3);
SMC_RET2(handle, ret, x2);
-
+ case RMM_EL3_FEATURES:
+ ret = rmm_el3_ifc_get_feat_register(x1, &x2);
+ SMC_RET2(handle, ret, x2);
+#if RMMD_ENABLE_EL3_TOKEN_SIGN
+ case RMM_EL3_TOKEN_SIGN:
+ return rmmd_el3_token_sign(handle, x1, x2, x3, x4);
+#endif
case RMM_BOOT_COMPLETE:
VERBOSE("RMMD: running rmmd_rmm_sync_exit\n");
rmmd_rmm_sync_exit(x1);
diff --git a/services/std_svc/rmmd/rmmd_private.h b/services/std_svc/rmmd/rmmd_private.h
index 6d3b5ec..0ce104d 100644
--- a/services/std_svc/rmmd/rmmd_private.h
+++ b/services/std_svc/rmmd/rmmd_private.h
@@ -51,6 +51,8 @@
uint64_t *remaining_len);
int rmmd_attest_get_signing_key(uint64_t buf_pa, uint64_t *buf_size,
uint64_t ecc_curve);
+uint64_t rmmd_el3_token_sign(void *handle, uint64_t x1, uint64_t x2,
+ uint64_t x3, uint64_t x4);
/* Assembly helpers */
uint64_t rmmd_rmm_enter(uint64_t *c_rt_ctx);