Merge pull request #8153 from LinuxJedi/Pi-pico

Add support for Raspberry Pi Pico

wolfcrypt/benchmark/benchmark.c

@@ -14498,7 +14498,15 @@ void bench_sphincsKeySign(byte level, byte optim)
 
         return (double) ticks/TICKS_PER_SECOND;
     }
+#elif defined(WOLFSSL_RPIPICO)
+    #include "pico/stdlib.h"
 
+    double current_time(int reset)
+    {
+        (void)reset;
+
+        return (double) time_us_64() / 1000000;
+    }
 #elif defined(THREADX)
     #include "tx_api.h"
     double current_time(int reset)

wolfcrypt/src/include.am

@@ -147,7 +147,9 @@ EXTRA_DIST += wolfcrypt/src/port/ti/ti-aes.c \
               wolfcrypt/src/port/cypress/psoc6_crypto.c \
               wolfcrypt/src/port/liboqs/liboqs.c \
               wolfcrypt/src/port/maxim/max3266x.c \
-              wolfcrypt/src/ASN_TEMPLATE.md
+              wolfcrypt/src/ASN_TEMPLATE.md \
+              wolfcrypt/src/port/rpi_pico/pico.c \
+              wolfcrypt/src/port/rpi_pico/README.md
 
 $(ASYNC_FILES):
 	$(AM_V_at)touch $(srcdir)/$@

wolfcrypt/src/port/rpi_pico/README.md

@@ -0,0 +1,72 @@
+# wolfSSL Raspberry Pi Pico Acceleration
+
+wolfSSL supports RNG acceleration on the Raspberry Pi RP2040 and RP2350
+microcontrollers. Everything here assumes you are using the standard [Raspberry
+Pi Pico SDK](https://github.com/raspberrypi/pico-sdk).
+
+It has only been tested with the ARM cores of the RP2350, not the RISC-V cores.
+
+## RNG Acceleration
+
+The Pico SDK has RNG functions for both the RP2040 and RP2350. In the RP2040
+this is an optimised PRNG method, in the RP2350 it uses a built-in TRNG. The
+same API is used for both.
+
+## Compiling wolfSSL
+
+In your `user_settings.h`, you should set the following to add support in
+wolfSSL:
+
+```c
+#define WOLFSSL_RPIPICO
+```
+
+Then for an RP2040, enable the ARM Thumb instructions:
+
+```c
+#define WOLFSSL_SP_ARM_THUMB_ASM
+```
+
+or for an RP2350, the Cortex-M instructions should be used:
+
+```c
+#define WOLFSSL_SP_ARM_CORTEX_M_ASM
+```
+
+To enable the RNG acceleration add the following:
+
+```c
+#define WC_NO_HASHDRBG
+#define CUSTOM_RAND_GENERATE_BLOCK wc_pico_rng_gen_block
+```
+
+In CMake you should add the following linking to both wolfSSL and the end
+application:
+
+```cmake
+target_link_libraries(wolfssl
+    pico_stdlib
+    pico_rand
+)
+```
+
+A full example can be found in the
+[`RPi-Pico`](https://github.com/wolfSSL/wolfssl-examples/tree/master/RPi-Pico)
+directory of the
+[`wolfssl-examples`](https://github.com/wolfSSL/wolfssl-examples) GitHub
+repository.
+
+## Note on RP2350 SHA256
+
+Although RP2350 has SHA256 acceleration, we cannot use this. It is because
+we need to get an intermediate result using `wc_Sha256GetHash()`. The hardware
+will only deal with 64byte packets of data, so to get a result we need to do
+SHA padding. Once the SHA padding is done, it is not in a state to add more
+data.
+The only real workaround would be to cache everything being sent into the
+hardware and replay it as a new instance when trying to get an intermediate
+result. This would not very efficient for an embedded device.
+
+## Support
+
+For questions please email [email protected]

wolfcrypt/src/port/rpi_pico/pico.c

@@ -0,0 +1,59 @@
+/* pico.c
+ *
+ * Copyright (C) 2024 wolfSSL Inc.
+ *
+ * This file is part of wolfSSL.
+ *
+ * wolfSSL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+
+
+
+#include <inttypes.h>
+#include <string.h>
+#include <wolfssl/wolfcrypt/settings.h>
+#include <wolfssl/wolfcrypt/types.h>
+
+#if defined(WOLFSSL_RPIPICO)
+#include "pico/rand.h"
+
+
+/* On RP2040 this uses an optimized PRNG, on RP2350 this uses a hardware TRNG.
+ * There is a 128bit function, but internally this is just 2x 64bit calls.
+ * Likewise the 32bit call is just a truncated 64bit call, so just stick with
+ * the 64bit calls.
+ */
+
+int wc_pico_rng_gen_block(unsigned char *output, unsigned int sz)
+{
+    uint32_t i = 0;
+
+    while (i < sz)
+    {
+        uint64_t rnd = get_rand_64();
+        if (i + 8 < sz)
+        {
+            XMEMCPY(output + i, &rnd, 8);
+            i += 8;
+        } else {
+            XMEMCPY(output + i, &rnd, sz - i);
+            i = sz;
+        }
+    }
+
+    return 0;
+}
+#endif

wolfcrypt/src/random.c

@@ -111,6 +111,8 @@ This library contains implementation for the random number generator.
     #include <random.h>
 #elif defined(WOLFSSL_XILINX_CRYPT_VERSAL)
     #include "wolfssl/wolfcrypt/port/xilinx/xil-versal-trng.h"
+#elif defined(WOLFSSL_RPIPICO)
+    #include "wolfssl/wolfcrypt/port/rpi_pico/pico.h"
 #elif defined(NO_DEV_RANDOM)
 #elif defined(CUSTOM_RAND_GENERATE)
 #elif defined(CUSTOM_RAND_GENERATE_BLOCK)
@@ -2968,7 +2970,6 @@ int wc_GenerateSeed(OS_Seed* os, byte* output, word32 sz)
         }
         return RAN_BLOCK_E;
     }
-
 #elif !defined(WOLFSSL_CAAM) && \
     (defined(FREESCALE_MQX) || defined(FREESCALE_KSDK_MQX) || \
      defined(FREESCALE_KSDK_BM) || defined(FREESCALE_FREE_RTOS))

wolfssl/wolfcrypt/include.am

@@ -119,7 +119,8 @@ noinst_HEADERS+= \
                          wolfssl/wolfcrypt/port/Renesas/renesas_tsip_types.h \
                          wolfssl/wolfcrypt/port/cypress/psoc6_crypto.h \
                          wolfssl/wolfcrypt/port/maxim/max3266x.h \
-                         wolfssl/wolfcrypt/port/maxim/max3266x-cryptocb.h
+                         wolfssl/wolfcrypt/port/maxim/max3266x-cryptocb.h \
+                         wolfssl/wolfcrypt/port/rpi_pico/pico.h
 
 if BUILD_CRYPTOAUTHLIB
 nobase_include_HEADERS+= wolfssl/wolfcrypt/port/atmel/atmel.h

wolfssl/wolfcrypt/port/rpi_pico/pico.h

@@ -0,0 +1,29 @@
+/* pico.h
+ *
+ * Copyright (C) 2024 wolfSSL Inc.
+ *
+ * This file is part of wolfSSL.
+ *
+ * wolfSSL is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * wolfSSL is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
+ */
+
+#ifndef _WOLFPORT_RPIPICO_H_
+#define _WOLFPORT_RPIPICO_H_
+#if defined(WOLFSSL_RPIPICO)
+
+WOLFSSL_LOCAL int wc_pico_rng_gen_block(unsigned char* output, unsigned int sz);
+
+#endif /* WOLFSSL_RPPICO */
+#endif /* _WOLFPORT_RPIPICO_H_ */

wolfssl/wolfcrypt/settings.h

@@ -264,6 +264,9 @@
 /* Uncomment next line if using MAXQ108x */
 /* #define WOLFSSL_MAXQ108X */
 
+/* Uncomment next line if using Raspberry Pi RP2040 or RP2350 */
+/* #define WOLFSSL_RPIPICO */
+
 /* Check PLATFORMIO first, as it may define other known environments. */
 #ifdef PLATFORMIO
     #ifdef ESP_PLATFORM