feat: Use hardware acceleration for exponent mpi.

Author: AnthonyGrondin

.cargo/config.toml

@@ -42,3 +42,12 @@ build-std = ["core"]
 
 [alias]
 xtask = "run --manifest-path ./xtask/Cargo.toml --"
+
+
+# Alias' for quickly building for different chips or running examples
+# By default we enable
+#   - `default` HAL features to set up basic chip specific settings
+esp32 =   "run --features   esp32 --target xtensa-esp32-none-elf        --features esp32-hal/default"
+esp32s2 = "run --features esp32s2 --target xtensa-esp32s2-none-elf      --features esp32s2-hal/default"
+esp32s3 = "run --features esp32s3 --target xtensa-esp32s3-none-elf      --features esp32s3-hal/default"
+esp32c3 = "run --features esp32c3 --target riscv32imc-unknown-none-elf  --features esp32c3-hal/default"

Cargo.toml

@@ -68,7 +68,9 @@ static_cell = { version = "=1.2", features = ["nightly"] }
 
 esp-mbedtls = { path = "./esp-mbedtls" }
 
-[target.xtensa-esp32s3-none-elf.dependencies]
+[[example]]
+name = "crypto_self_test"
+required-features = ["esp-wifi/wifi-logs"]
 
 [[example]]
 name = "async_client"

esp-mbedtls-sys/headers/esp32c3/config.h

@@ -326,6 +326,7 @@
 //#define MBEDTLS_ECJPAKE_ALT
 //#define MBEDTLS_GCM_ALT
 //#define MBEDTLS_NIST_KW_ALT
+#define MBEDTLS_MPI_EXP_MOD_ALT_FALLBACK
 //#define MBEDTLS_MD5_ALT
 //#define MBEDTLS_POLY1305_ALT
 //#define MBEDTLS_RIPEMD160_ALT

esp-mbedtls-sys/headers/esp32s2/config.h

@@ -326,6 +326,7 @@
 //#define MBEDTLS_ECJPAKE_ALT
 //#define MBEDTLS_GCM_ALT
 //#define MBEDTLS_NIST_KW_ALT
+#define MBEDTLS_MPI_EXP_MOD_ALT_FALLBACK
 //#define MBEDTLS_MD5_ALT
 //#define MBEDTLS_POLY1305_ALT
 //#define MBEDTLS_RIPEMD160_ALT

esp-mbedtls-sys/headers/esp32s3/config.h

@@ -326,6 +326,7 @@
 //#define MBEDTLS_ECJPAKE_ALT
 //#define MBEDTLS_GCM_ALT
 //#define MBEDTLS_NIST_KW_ALT
+#define MBEDTLS_MPI_EXP_MOD_ALT_FALLBACK
 //#define MBEDTLS_MD5_ALT
 //#define MBEDTLS_POLY1305_ALT
 //#define MBEDTLS_RIPEMD160_ALT

esp-mbedtls-sys/include/include.h

@@ -8,3 +8,10 @@
 #include "mbedtls/debug.h"
 #include "mbedtls/ctr_drbg.h"
 #include "psa/crypto_values.h"
+
+// Provides a function prototype to generate bindings for mbedtls_mpi_exp_mod_soft()
+#if defined(MBEDTLS_MPI_EXP_MOD_ALT_FALLBACK)
+  int mbedtls_mpi_exp_mod_soft(mbedtls_mpi *X, const mbedtls_mpi *A,
+      const mbedtls_mpi *E, const mbedtls_mpi *N,
+      mbedtls_mpi *prec_RR);
+#endif

esp-mbedtls-sys/src/include/esp32c3.rs

@@ -22495,3 +22495,12 @@ extern "C" {
     /// \return              \c 1 on failure.
     pub fn mbedtls_ctr_drbg_self_test(verbose: crate::c_types::c_int) -> crate::c_types::c_int;
 }
+extern "C" {
+    pub fn mbedtls_mpi_exp_mod_soft(
+        X: *mut mbedtls_mpi,
+        A: *const mbedtls_mpi,
+        E: *const mbedtls_mpi,
+        N: *const mbedtls_mpi,
+        prec_RR: *mut mbedtls_mpi,
+    ) -> crate::c_types::c_int;
+}

esp-mbedtls-sys/src/include/esp32s2.rs

@@ -22492,3 +22492,12 @@ extern "C" {
     /// \return              \c 1 on failure.
     pub fn mbedtls_ctr_drbg_self_test(verbose: crate::c_types::c_int) -> crate::c_types::c_int;
 }
+extern "C" {
+    pub fn mbedtls_mpi_exp_mod_soft(
+        X: *mut mbedtls_mpi,
+        A: *const mbedtls_mpi,
+        E: *const mbedtls_mpi,
+        N: *const mbedtls_mpi,
+        prec_RR: *mut mbedtls_mpi,
+    ) -> crate::c_types::c_int;
+}

esp-mbedtls-sys/src/include/esp32s3.rs

@@ -22492,3 +22492,12 @@ extern "C" {
     /// \return              \c 1 on failure.
     pub fn mbedtls_ctr_drbg_self_test(verbose: crate::c_types::c_int) -> crate::c_types::c_int;
 }
+extern "C" {
+    pub fn mbedtls_mpi_exp_mod_soft(
+        X: *mut mbedtls_mpi,
+        A: *const mbedtls_mpi,
+        E: *const mbedtls_mpi,
+        N: *const mbedtls_mpi,
+        prec_RR: *mut mbedtls_mpi,
+    ) -> crate::c_types::c_int;
+}

esp-mbedtls/Cargo.toml

@@ -9,10 +9,12 @@ esp-mbedtls-sys = { path = "../esp-mbedtls-sys" }
 log = "0.4.17"
 embedded-io = { version = "0.6.1" }
 embedded-io-async = { version = "0.6.0", optional = true }
+crypto-bigint = { version = "0.5.3", default-features = false, features = ["extra-sizes"] }
 esp32-hal = { version = "0.18.0", optional = true }
 esp32c3-hal = { version = "0.15.0", optional = true }
 esp32s2-hal = { version = "0.15.0", optional = true }
 esp32s3-hal = { version = "0.15.0", optional = true }
+cfg-if = "1.0.0"
 
 [features]
 async = ["dep:embedded-io-async"]