sys/psa_crypto: chacha20 multipart glue code

cpu/nrf52/Makefile.features

@@ -20,6 +20,7 @@ ifneq (,$(filter nrf52840xxaa,$(CPU_MODEL)))
   FEATURES_PROVIDED += periph_hash_sha_512
   FEATURES_PROVIDED += periph_hmac_sha_256
   FEATURES_PROVIDED += periph_cipher_aes_128_cbc
+  FEATURES_PROVIDED += periph_cipher_chacha20
   FEATURES_PROVIDED += periph_ecc_p192r1
   FEATURES_PROVIDED += periph_ecc_p256r1
   FEATURES_PROVIDED += periph_ecc_ed25519

cpu/nrf52/periph/Makefile.dep

@@ -38,6 +38,11 @@ ifneq (,$(filter periph_cipher_aes_128_cbc,$(USEMODULE)))
   USEMODULE += psa_cryptocell_310_aes_cbc
 endif
 
+ifneq (,$(filter periph_cipher_chacha20,$(USEMODULE)))
+  USEPKG += driver_cryptocell_310
+  USEMODULE += psa_cryptocell_310_cipher_chacha20
+endif
+
 ifneq (,$(filter periph_hmac_sha_256,$(USEMODULE)))
   USEPKG += driver_cryptocell_310
   USEMODULE += psa_cryptocell_310_hmac

features.yaml

@@ -851,6 +851,8 @@ groups:
       help: A Hardware Random Number Generator (HWRNG) peripheral is present.
     - name: periph_cipher_aes_128_cbc
       help: AES 128 CBC hardware acceleration present
+    - name: periph_cipher_chacha20
+      help: ChaCha20 hardware acceleration present
     - name: periph_ecc_p192r1
       help: ECC P192R1 hardware acceleration peripheral present.
     - name: periph_ecc_p256r1

makefiles/features_existing.inc.mk

@@ -139,6 +139,7 @@ FEATURES_EXISTING := \
     periph_adc_continuous \
     periph_can \
     periph_cipher_aes_128_cbc \
+    periph_cipher_chacha20 \
     periph_clic \
     periph_coretimer \
     periph_cpuid \

makefiles/features_modules.inc.mk

@@ -12,6 +12,7 @@ USEMODULE += $(PERIPH_FEATURES)
 # Add all USED periph_% init modules unless they are blacklisted
 PERIPH_IGNORE_MODULES := \
   periph_cipher_aes_128_cbc \
+  periph_cipher_chacha20 \
   periph_clic \
   periph_common \
   periph_coretimer \

makefiles/pseudomodules.inc.mk

@@ -357,6 +357,7 @@ PSEUDOMODULES += psa_riot_cipher_aes_128_ecb
 PSEUDOMODULES += psa_riot_cipher_aes_128_cbc
 PSEUDOMODULES += psa_riot_cipher_aes_192_cbc
 PSEUDOMODULES += psa_riot_cipher_aes_256_cbc
+PSEUDOMODULES += psa_riot_cipher_chacha20
 PSEUDOMODULES += psa_riot_hashes_md5
 PSEUDOMODULES += psa_riot_hashes_sha_1
 PSEUDOMODULES += psa_riot_hashes_sha_224

pkg/driver_cryptocell_310/Makefile.include

@@ -13,6 +13,7 @@ CFLAGS += -Wno-cast-align
 
 PSEUDOMODULES += psa_cryptocell_310_aes_cbc
 PSEUDOMODULES += psa_cryptocell_310_aes_common
+PSEUDOMODULES += psa_cryptocell_310_cipher_chacha20
 PSEUDOMODULES += psa_cryptocell_310_ecc_common
 PSEUDOMODULES += psa_cryptocell_310_ecc_p192
 PSEUDOMODULES += psa_cryptocell_310_ecc_p256

pkg/driver_cryptocell_310/include/cryptocell_310_util.h

@@ -23,6 +23,10 @@
 extern "C" {
 #endif
 
+#ifdef CPU_NRF52
+#define CHECK_POINTER_DMA_ACCESS(p) ((unsigned int)p >= 0x20000000 ? (unsigned int)p < 0x40000000 : 0)
+#endif
+
 /**
  * @brief   Enable CryptoCell module and IRQs.
  *

pkg/driver_cryptocell_310/include/psa_error.h

@@ -28,6 +28,7 @@ extern "C" {
 #include "crys_ec_mont_edw_error.h"
 #include "crys_hash_error.h"
 #include "ssi_aes_error.h"
+#include "crys_chacha_error.h"
 
 /**
  * @brief   Convert CryptoCell CRYS errors to PSA status values

pkg/driver_cryptocell_310/include/psa_periph_chacha20_ctx.h

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2024 TU Dresden
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     pkg_driver_cryptocell_310
+ * @{
+ *
+ * @file
+ * @brief       CryptoCell 310 driver specific ChaCha20 contexts
+ *
+ * @author      Lennard Melling <lennard.melling@msx.tu-dresden.de>
+ *
+ */
+#ifndef PSA_PERIPH_CHACHA20_CTX_H
+#define PSA_PERIPH_CHACHA20_CTX_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "crys_chacha.h"
+#include "kernel_defines.h"
+
+#if IS_USED(MODULE_PERIPH_CIPHER_CHACHA20) || DOXYGEN
+/**
+ * @brief This struct is used to handle the discontinuity between the PSA API
+ * and the CRYS ChaCha20 API. The PSA API psa_cipher_update() function allows any size
+ * of input array, but the CRYS implementation only works on multiples of 64B.
+ * So we store any remainders from the input in the buffer, and if any more data
+ * is input, we join them with the buffer values. The psa_cipher_finish() function
+ * will then xcrypt the remaining buffer values.
+ * The buffer is also used in the setup of the operation. The psa_cipher_~_setup()
+ * functions only provide the key for the operation, but the CRYS ChaCha20
+ * implementation also needs the counter and nonce provided by psa_cipher_set_iv().
+ * So we store the key in the buffer until it is needed in the CRYS ChaCha20 setup.
+ */
+typedef struct {
+    uint8_t buffer[CRYS_CHACHA_BLOCK_SIZE_IN_BYTES];    /**< Block buffer */
+    uint8_t buffer_length;                              /**< Current length of the data in buffer */
+    union {
+        CRYS_CHACHA_EncryptMode_t mode;                 /**< Mode of the operation */
+        CRYS_CHACHAUserContext_t post_setup;            /**< Context of the CRYS ChaCha20 operation */
+    } ctx;                                              /**< Context Setup values */
+} psa_cipher_chacha20_ctx_t;
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PSA_PERIPH_CHACHA20_CTX_H */
+/** @} */