diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum.h b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum.h
index 5ead8cc6f..b6d6f1c1f 100644
--- a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum.h
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum.h
@@ -13,68 +13,8 @@
 // limitations under the License.
 #pragma once
 
-#include_next "mbedtls/bignum.h"
-#include "sdkconfig.h"
-
-/**
- * This is a wrapper for the main mbedtls/bignum.h. This wrapper
- * provides a few additional ESP32-only functions.
- *
- * This is because we don't set MBEDTLS_BIGNUM_ALT in the same way we
- * do for AES, SHA, etc. Because we still use most of the bignum.h
- * implementation and just replace a few hardware accelerated
- * functions (see MBEDTLS_MPI_EXP_MOD_ALT & MBEDTLS_MPI_MUL_MPI_ALT in
- * esp_config.h).
- *
- * @note Unlike the other hardware accelerator support functions in esp32/hwcrypto, there is no
- * generic "hwcrypto/bignum.h" header for using these functions without mbedTLS. The reason for this
- * is that all of the function implementations depend strongly upon the mbedTLS MPI implementation.
- */
-
-/**
- * @brief Lock access to RSA Accelerator (MPI/bignum operations)
- *
- * RSA Accelerator hardware unit can only be used by one
- * consumer at a time.
- *
- * @note This function is non-recursive (do not call it twice from the
- * same task.)
- *
- * @note You do not need to call this if you are using the mbedTLS bignum.h
- * API or esp_mpi_xxx functions. This function is only needed if you
- * want to call ROM RSA functions or access the registers directly.
- *
- */
-void esp_mpi_acquire_hardware(void);
-
-/**
- * @brief Unlock access to RSA Accelerator (MPI/bignum operations)
- *
- * Has to be called once for each call to esp_mpi_acquire_hardware().
- *
- * @note You do not need to call this if you are using the mbedTLS bignum.h
- * API or esp_mpi_xxx functions. This function is only needed if you
- * want to call ROM RSA functions or access the registers directly.
- */
-void esp_mpi_release_hardware(void);
-
-//#if CONFIG_MBEDTLS_HARDWARE_MPI
-
-/* @brief MPI modular mupltiplication function
- *
- * Calculates Z = (X * Y) mod M using MPI hardware acceleration.
- *
- * This is not part of the standard mbedTLS bignum API.
- *
- * @note All of X, Y & Z should be less than 4096 bit long or an error is returned.
- *
- * @param Z Result bignum, should be pre-initialised with mbedtls_mpi_init().
- * @param X First multiplication argument.
- * @param Y Second multiplication argument.
- * @param M Modulus value for result.
- *
- * @return 0 on success, mbedTLS MPI error codes on failure.
- */
-int esp_mpi_mul_mpi_mod(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M);
-
-//#endif // CONFIG_MBEDTLS_HARDWARE_MPI
+#if CONFIG_IDF_TARGET_ESP32
+#include "bignum_ESP32.h"
+#elif CONFIG_IDF_TARGET_ESP32C3
+#include "bignum_ESP32_C3.h"
+#endif
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.c b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.c
new file mode 100644
index 000000000..1a63ffe7f
--- /dev/null
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.c
@@ -0,0 +1,291 @@
+/**
+ * \brief  Multi-precision integer library, ESP-IDF hardware accelerated parts
+ *
+ *  based on mbedTLS implementation
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Additions Copyright (C) 2016-2020, Espressif Systems (Shanghai) PTE Ltd
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+#if CONFIG_IDF_TARGET_ESP32
+#if __has_include("esp_idf_version.h")
+#include "esp_idf_version.h"
+#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(4, 0, 0)
+#warning("IDF is 4 or later")
+#include "soc/hwcrypto_periph.h"
+#endif
+#endif
+
+#include "soc/hwcrypto_reg.h"
+#include "driver/periph_ctrl.h"
+#include <mbedtls/bignum.h>
+#include "bignum_impl.h"
+#include <sys/param.h>
+#include <sys/lock.h>
+#if CONFIG_IDF_TARGET_ESP32C3
+#include "esp32c3/dport_access.h"
+#endif 
+
+static _lock_t mpi_lock;
+
+/* Round up number of words to nearest
+   512 bit (16 word) block count.
+*/
+size_t esp_mpi_hardware_words(size_t words)
+{
+    return (words + 0xF) & ~0xF;
+}
+
+void esp_mpi_enable_hardware_hw_op( void )
+{
+    /* newlib locks lazy initialize on ESP-IDF */
+    _lock_acquire(&mpi_lock);
+
+    /* Enable RSA hardware */
+    periph_module_enable(PERIPH_RSA_MODULE);
+    DPORT_REG_CLR_BIT(DPORT_RSA_PD_CTRL_REG, DPORT_RSA_PD);
+
+    while (DPORT_REG_READ(RSA_CLEAN_REG) != 1)
+    { }
+    // Note: from enabling RSA clock to here takes about 1.3us
+}
+
+void esp_mpi_disable_hardware_hw_op( void )
+{
+    DPORT_REG_SET_BIT(DPORT_RSA_PD_CTRL_REG, DPORT_RSA_PD);
+
+    /* Disable RSA hardware */
+    periph_module_disable(PERIPH_RSA_MODULE);
+
+    _lock_release(&mpi_lock);
+}
+
+
+/* Copy mbedTLS MPI bignum 'mpi' to hardware memory block at 'mem_base'.
+
+   If hw_words is higher than the number of words in the bignum then
+   these additional words will be zeroed in the memory buffer.
+
+*/
+static inline void mpi_to_mem_block(uint32_t mem_base, const mbedtls_mpi *mpi, size_t hw_words)
+{
+    uint32_t *pbase = (uint32_t *)mem_base;
+    uint32_t copy_words = MIN(hw_words, mpi->n);
+
+    /* Copy MPI data to memory block registers */
+    for (int i = 0; i < copy_words; i++) {
+        pbase[i] = mpi->p[i];
+    }
+
+    /* Zero any remaining memory block data */
+    for (int i = copy_words; i < hw_words; i++) {
+        pbase[i] = 0;
+    }
+}
+
+/* Read mbedTLS MPI bignum back from hardware memory block.
+
+   Reads num_words words from block.
+
+   Bignum 'x' should already be grown to at least num_words by caller (can be done while
+   calculation is in progress, to save some cycles)
+*/
+static inline void mem_block_to_mpi(mbedtls_mpi *x, uint32_t mem_base, int num_words)
+{
+    assert(x->n >= num_words);
+
+    /* Copy data from memory block registers */
+    esp_dport_access_read_buffer(x->p, mem_base, num_words);
+
+    /* Zero any remaining limbs in the bignum, if the buffer is bigger
+       than num_words */
+    for (size_t i = num_words; i < x->n; i++) {
+        x->p[i] = 0;
+    }
+}
+
+
+/* Begin an RSA operation. op_reg specifies which 'START' register
+   to write to.
+*/
+static inline void start_op(uint32_t op_reg)
+{
+    /* Clear interrupt status */
+    DPORT_REG_WRITE(RSA_INTERRUPT_REG, 1);
+
+    /* Note: above REG_WRITE includes a memw, so we know any writes
+       to the memory blocks are also complete. */
+
+    DPORT_REG_WRITE(op_reg, 1);
+}
+
+/* Wait for an RSA operation to complete.
+*/
+static inline void wait_op_complete(void)
+{
+    while (DPORT_REG_READ(RSA_INTERRUPT_REG) != 1)
+    { }
+
+    /* clear the interrupt */
+    DPORT_REG_WRITE(RSA_INTERRUPT_REG, 1);
+}
+
+/* Read result from last MPI operation */
+void esp_mpi_read_result_hw_op(mbedtls_mpi *Z, size_t z_words)
+{
+    wait_op_complete();
+    mem_block_to_mpi(Z, RSA_MEM_Z_BLOCK_BASE, z_words);
+}
+
+/* Z = (X * Y) mod M */
+void esp_mpi_mul_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t hw_words)
+{
+    /* Load M, X, Rinv, Mprime (Mprime is mod 2^32) */
+    mpi_to_mem_block(RSA_MEM_M_BLOCK_BASE, M, hw_words);
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, hw_words);
+    mpi_to_mem_block(RSA_MEM_RB_BLOCK_BASE, Rinv, hw_words);
+    DPORT_REG_WRITE(RSA_M_DASH_REG, (uint32_t)Mprime);
+
+    /* "mode" register loaded with number of 512-bit blocks, minus 1 */
+    DPORT_REG_WRITE(RSA_MULT_MODE_REG, (hw_words / 16) - 1);
+
+    /* Execute first stage montgomery multiplication */
+    start_op(RSA_MULT_START_REG);
+
+    wait_op_complete();
+
+    /* execute second stage */
+    /* Load Y to X input memory block, rerun */
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, Y, hw_words);
+
+    start_op(RSA_MULT_START_REG);
+}
+
+/* Z = X * Y */
+void esp_mpi_mul_mpi_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, size_t hw_words)
+{
+    /* Copy X (right-extended) & Y (left-extended) to memory block */
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, hw_words);
+    mpi_to_mem_block(RSA_MEM_Z_BLOCK_BASE + hw_words * 4, Y, hw_words);
+    /* NB: as Y is left-extended, we don't zero the bottom words_mult words of Y block.
+       This is OK for now because zeroing is done by hardware when we do esp_mpi_acquire_hardware().
+    */
+
+    DPORT_REG_WRITE(RSA_M_DASH_REG, 0);
+
+    /* "mode" register loaded with number of 512-bit blocks in result,
+       plus 7 (for range 9-12). (this is ((N~ / 32) - 1) + 8))
+    */
+    DPORT_REG_WRITE(RSA_MULT_MODE_REG, ((hw_words * 2) / 16) + 7);
+
+    start_op(RSA_MULT_START_REG);
+
+}
+
+
+int esp_mont_hw_op(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M,
+                   mbedtls_mpi_uint Mprime,
+                   size_t hw_words,
+                   bool again)
+{
+    // Note Z may be the same pointer as X or Y
+    int ret = 0;
+
+    // montgomery mult prepare
+    if (again == false) {
+        mpi_to_mem_block(RSA_MEM_M_BLOCK_BASE, M, hw_words);
+        DPORT_REG_WRITE(RSA_M_DASH_REG, Mprime);
+        DPORT_REG_WRITE(RSA_MULT_MODE_REG, hw_words / 16 - 1);
+    }
+
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, hw_words);
+    mpi_to_mem_block(RSA_MEM_RB_BLOCK_BASE, Y, hw_words);
+
+    start_op(RSA_MULT_START_REG);
+    Z->s = 1; // The sign of Z will be = M->s (but M->s is always 1)
+    MBEDTLS_MPI_CHK( mbedtls_mpi_grow(Z, hw_words) );
+
+    wait_op_complete();
+
+    /* Read back the result */
+    mem_block_to_mpi(Z, RSA_MEM_Z_BLOCK_BASE, hw_words);
+
+
+    /* from HAC 14.36 - 3. If Z >= M then Z = Z - M */
+    if (mbedtls_mpi_cmp_mpi(Z, M) >= 0) {
+        MBEDTLS_MPI_CHK(mbedtls_mpi_sub_mpi(Z, Z, M));
+    }
+cleanup:
+    return ret;
+}
+
+
+
+/* Special-case of mbedtls_mpi_mult_mpi(), where we use hardware montgomery mod
+   multiplication to calculate an mbedtls_mpi_mult_mpi result where either
+   A or B are >2048 bits so can't use the standard multiplication method.
+
+   Result (z_words, based on A bits + B bits) must still be less than 4096 bits.
+
+   This case is simpler than the general case modulo multiply of
+   esp_mpi_mul_mpi_mod() because we can control the other arguments:
+
+   * Modulus is chosen with M=(2^num_bits - 1) (ie M=R-1), so output
+   isn't actually modulo anything.
+   * Mprime and Rinv are therefore predictable as follows:
+   Mprime = 1
+   Rinv = 1
+
+   (See RSA Accelerator section in Technical Reference for more about Mprime, Rinv)
+*/
+void esp_mpi_mult_mpi_failover_mod_mult_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, size_t num_words)
+{
+    size_t hw_words = num_words;
+
+    /* M = 2^num_words - 1, so block is entirely FF */
+    for (int i = 0; i < hw_words; i++) {
+        DPORT_REG_WRITE(RSA_MEM_M_BLOCK_BASE + i * 4, UINT32_MAX);
+    }
+    /* Mprime = 1 */
+    DPORT_REG_WRITE(RSA_M_DASH_REG, 1);
+
+    /* "mode" register loaded with number of 512-bit blocks, minus 1 */
+    DPORT_REG_WRITE(RSA_MULT_MODE_REG, (hw_words / 16) - 1);
+
+    /* Load X */
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, hw_words);
+
+    /* Rinv = 1, write first word */
+    DPORT_REG_WRITE(RSA_MEM_RB_BLOCK_BASE, 1);
+
+    /* Zero out rest of the Rinv words */
+    for (int i = 1; i < hw_words; i++) {
+        DPORT_REG_WRITE(RSA_MEM_RB_BLOCK_BASE + i * 4, 0);
+    }
+
+    start_op(RSA_MULT_START_REG);
+
+    wait_op_complete();
+
+    /* finish the modular multiplication */
+    /* Load Y to X input memory block, rerun */
+    mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, Y, hw_words);
+
+    start_op(RSA_MULT_START_REG);
+
+}
+#endif //CONFIG_IDF_TARGET_ESP32
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.h b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.h
new file mode 100644
index 000000000..90c3325b5
--- /dev/null
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32.h
@@ -0,0 +1,82 @@
+// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#if CONFIG_IDF_TARGET_ESP32
+#pragma once
+
+#include_next "mbedtls/bignum.h"
+#include "sdkconfig.h"
+
+/**
+ * This is a wrapper for the main mbedtls/bignum.h. This wrapper
+ * provides a few additional ESP32-only functions.
+ *
+ * This is because we don't set MBEDTLS_BIGNUM_ALT in the same way we
+ * do for AES, SHA, etc. Because we still use most of the bignum.h
+ * implementation and just replace a few hardware accelerated
+ * functions (see MBEDTLS_MPI_EXP_MOD_ALT & MBEDTLS_MPI_MUL_MPI_ALT in
+ * esp_config.h).
+ *
+ * @note Unlike the other hardware accelerator support functions in esp32/hwcrypto, there is no
+ * generic "hwcrypto/bignum.h" header for using these functions without mbedTLS. The reason for this
+ * is that all of the function implementations depend strongly upon the mbedTLS MPI implementation.
+ */
+
+/**
+ * @brief Lock access to RSA Accelerator (MPI/bignum operations)
+ *
+ * RSA Accelerator hardware unit can only be used by one
+ * consumer at a time.
+ *
+ * @note This function is non-recursive (do not call it twice from the
+ * same task.)
+ *
+ * @note You do not need to call this if you are using the mbedTLS bignum.h
+ * API or esp_mpi_xxx functions. This function is only needed if you
+ * want to call ROM RSA functions or access the registers directly.
+ *
+ */
+void esp_mpi_acquire_hardware(void);
+
+/**
+ * @brief Unlock access to RSA Accelerator (MPI/bignum operations)
+ *
+ * Has to be called once for each call to esp_mpi_acquire_hardware().
+ *
+ * @note You do not need to call this if you are using the mbedTLS bignum.h
+ * API or esp_mpi_xxx functions. This function is only needed if you
+ * want to call ROM RSA functions or access the registers directly.
+ */
+void esp_mpi_release_hardware(void);
+
+//#if CONFIG_MBEDTLS_HARDWARE_MPI
+
+/* @brief MPI modular mupltiplication function
+ *
+ * Calculates Z = (X * Y) mod M using MPI hardware acceleration.
+ *
+ * This is not part of the standard mbedTLS bignum API.
+ *
+ * @note All of X, Y & Z should be less than 4096 bit long or an error is returned.
+ *
+ * @param Z Result bignum, should be pre-initialised with mbedtls_mpi_init().
+ * @param X First multiplication argument.
+ * @param Y Second multiplication argument.
+ * @param M Modulus value for result.
+ *
+ * @return 0 on success, mbedTLS MPI error codes on failure.
+ */
+int esp_mpi_mul_mpi_mod(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M);
+
+//#endif // CONFIG_MBEDTLS_HARDWARE_MPI
+#endif CONFIG_IDF_TARGET_ESP32
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.c b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.c
new file mode 100644
index 000000000..a96d514b9
--- /dev/null
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.c
@@ -0,0 +1,108 @@
+/**
+ * \brief  Multi-precision integer library, ESP-IDF hardware accelerated parts
+ *
+ *  based on mbedTLS implementation
+ *
+ *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
+ *  Additions Copyright (C) 2016-2020, Espressif Systems (Shanghai) PTE Ltd
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ */
+
+#if CONFIG_IDF_TARGET_ESP32C3
+#if __has_include("esp_idf_version.h")
+#include "esp_idf_version.h"
+#endif
+
+#include <sys/param.h>
+#include "soc/hwcrypto_periph.h"
+#include "driver/periph_ctrl.h"
+#include "mbedtls/bignum.h"
+#include "bignum_impl.h"
+#include "soc/system_reg.h"
+#include "soc/periph_defs.h"
+#include "esp_crypto_lock.h"
+
+/* Copy mbedTLS MPI bignum 'mpi' to hardware memory block at 'mem_base'.
+
+   If hw_words is higher than the number of words in the bignum then
+   these additional words will be zeroed in the memory buffer.
+
+*/
+static inline void mpi_to_mem_block(uint32_t mem_base, const mbedtls_mpi *mpi, size_t num_words)
+{
+    uint32_t *pbase = (uint32_t *)mem_base;
+    uint32_t copy_words = MIN(num_words, mpi->n);
+
+    /* Copy MPI data to memory block registers */
+    for (int i = 0; i < copy_words; i++) {
+        pbase[i] = mpi->p[i];
+    }
+
+    /* Zero any remaining memory block data */
+    for (int i = copy_words; i < num_words; i++) {
+        pbase[i] = 0;
+    }
+}
+
+/* Read mbedTLS MPI bignum back from hardware memory block.
+
+   Reads num_words words from block.
+
+   Bignum 'x' should already be grown to at least num_words by caller (can be done while
+   calculation is in progress, to save some cycles)
+*/
+static inline void mem_block_to_mpi(mbedtls_mpi *x, uint32_t mem_base, int num_words)
+{
+
+    /* Copy data from memory block registers */
+    const size_t REG_WIDTH = sizeof(uint32_t);
+    for (size_t i = 0; i < num_words; i++) {
+        x->p[i] = REG_READ(mem_base + (i * REG_WIDTH));
+    }
+    /* Zero any remaining limbs in the bignum, if the buffer is bigger
+       than num_words */
+    for (size_t i = num_words; i < x->n; i++) {
+        x->p[i] = 0;
+    }
+
+}
+
+/* Begin an RSA operation. op_reg specifies which 'START' register
+   to write to.
+*/
+static inline void start_op(uint32_t op_reg)
+{
+    /* Clear interrupt status */
+    REG_WRITE(RSA_CLEAR_INTERRUPT_REG, 1);
+
+    /* Note: above REG_WRITE includes a memw, so we know any writes
+       to the memory blocks are also complete. */
+
+    REG_WRITE(op_reg, 1);
+}
+
+/* Wait for an RSA operation to complete.
+*/
+static inline void wait_op_complete(void)
+{
+    while (REG_READ(RSA_QUERY_INTERRUPT_REG) != 1)
+    { }
+
+    /* clear the interrupt */
+    REG_WRITE(RSA_CLEAR_INTERRUPT_REG, 1);
+}
+
+#endif //CONFIG_IDF_TARGET_ESP32C3
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.h b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.h
new file mode 100644
index 000000000..333615c3f
--- /dev/null
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_ESP32_C3.h
@@ -0,0 +1,87 @@
+// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#if CONFIG_IDF_TARGET_ESP32C3
+#pragma once
+
+#include_next "mbedtls/bignum.h"
+#include "sdkconfig.h"
+
+/**
+ * This is a wrapper for the main mbedtls/bignum.h. This wrapper
+ * provides a few additional ESP32-only functions.
+ *
+ * This is because we don't set MBEDTLS_BIGNUM_ALT in the same way we
+ * do for AES, SHA, etc. Because we still use most of the bignum.h
+ * implementation and just replace a few hardware accelerated
+ * functions (see MBEDTLS_MPI_EXP_MOD_ALT & MBEDTLS_MPI_MUL_MPI_ALT in
+ * esp_config.h).
+ *
+ * @note Unlike the other hardware accelerator support functions in esp32/hwcrypto, there is no
+ * generic "hwcrypto/bignum.h" header for using these functions without mbedTLS. The reason for this
+ * is that all of the function implementations depend strongly upon the mbedTLS MPI implementation.
+ */
+
+/**
+ * @brief Lock access to RSA Accelerator (MPI/bignum operations)
+ *
+ * RSA Accelerator hardware unit can only be used by one
+ * consumer at a time.
+ *
+ * @note This function is non-recursive (do not call it twice from the
+ * same task.)
+ *
+ * @note You do not need to call this if you are using the mbedTLS bignum.h
+ * API or esp_mpi_xxx functions. This function is only needed if you
+ * want to call ROM RSA functions or access the registers directly.
+ *
+ */
+void esp_mpi_acquire_hardware(void);
+
+/**
+ * @brief Unlock access to RSA Accelerator (MPI/bignum operations)
+ *
+ * Has to be called once for each call to esp_mpi_acquire_hardware().
+ *
+ * @note You do not need to call this if you are using the mbedTLS bignum.h
+ * API or esp_mpi_xxx functions. This function is only needed if you
+ * want to call ROM RSA functions or access the registers directly.
+ */
+void esp_mpi_release_hardware(void);
+
+//#if CONFIG_MBEDTLS_HARDWARE_MPI
+
+/* @brief MPI modular mupltiplication function
+ *
+ * Calculates Z = (X * Y) mod M using MPI hardware acceleration.
+ *
+ * This is not part of the standard mbedTLS bignum API.
+ *
+ * @note All of X, Y & Z should be less than 4096 bit long or an error is returned.
+ *
+ * @param Z Result bignum, should be pre-initialised with mbedtls_mpi_init().
+ * @param X First multiplication argument.
+ * @param Y Second multiplication argument.
+ * @param M Modulus value for result.
+ *
+ * @return 0 on success, mbedTLS MPI error codes on failure.
+ */
+int esp_mpi_mul_mpi_mod(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M);
+
+void esp_mpi_mul_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t num_words);
+static inline void mpi_to_mem_block(uint32_t mem_base, const mbedtls_mpi *mpi, size_t num_words);
+void esp_mpi_mul_mpi_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, size_t num_words);
+
+
+//#endif // CONFIG_MBEDTLS_HARDWARE_MPI
+#endif //CONFIG_IDF_TARGET_ESP32C3
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_impl.h b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_impl.h
index 0c70fa339..20943499b 100644
--- a/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_impl.h
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/bignum_impl.h
@@ -10,7 +10,7 @@
    exponentiation instead.
 */
 
-#define CONFIG_IDF_TARGET_ESP32  1
+// #define CONFIG_IDF_TARGET_ESP32  1
 
 #if CONFIG_IDF_TARGET_ESP32
 #define ESP_MPI_USE_MONT_EXP
@@ -19,7 +19,7 @@
 //#define MBEDTLS_MPI_MUL_MPI_ALT
 #endif
 
-
+#if CONFIG_IDF_TARGET_ESP32
 int esp_mpi_exp_mod( mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, mbedtls_mpi *_Rinv );
 
 /**
@@ -86,7 +86,11 @@ int esp_mont_hw_op(mbedtls_mpi* Z, const mbedtls_mpi* X, const mbedtls_mpi* Y, c
  *
  */
 void esp_mpi_exp_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t hw_words);
-
+#endif //CONFIG_IDF_TARGET_ESP32
 #endif //ESP_MPI_USE_MONT_EXP
 
+#if CONFIG_IDF_TARGET_ESP32C3
+void esp_mpi_exp_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t num_words);
+#endif //CONFIG_IDF_TARGET_ESP32C3
+
 #endif
diff --git a/lib/libesp32_div/ESP32-HomeKit/src/port/esp_bignum.c b/lib/libesp32_div/ESP32-HomeKit/src/port/esp_bignum.c
index 44e0a798c..8d6936e60 100644
--- a/lib/libesp32_div/ESP32-HomeKit/src/port/esp_bignum.c
+++ b/lib/libesp32_div/ESP32-HomeKit/src/port/esp_bignum.c
@@ -79,7 +79,7 @@ static inline size_t bits_to_words(size_t bits)
 /* Return the number of words actually used to represent an mpi
    number.
 */
-#if defined(MBEDTLS_MPI_EXP_MOD_ALT)
+#if defined(MBEDTLS_MPI_EXP_MOD_ALT) || defined(CONFIG_IDF_TARGET_ESP32C3)
 static size_t mpi_words(const mbedtls_mpi *mpi)
 {
     for (size_t i = mpi->n; i > 0; i--) {
@@ -369,6 +369,87 @@ cleanup:
 
 #endif /* MBEDTLS_MPI_EXP_MOD_ALT */
 
+#if CONFIG_IDF_TARGET_ESP32C3
+int esp_mpi_exp_mod( mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, mbedtls_mpi *_Rinv )
+{
+    int ret = 0;
+    size_t x_words = mpi_words(X);
+    size_t y_words = mpi_words(Y);
+    size_t m_words = mpi_words(M);
+
+
+    /* "all numbers must be the same length", so choose longest number
+       as cardinal length of operation...
+    */
+    size_t num_words = esp_mpi_hardware_words(MAX(m_words, MAX(x_words, y_words)));
+
+    mbedtls_mpi Rinv_new; /* used if _Rinv == NULL */
+    mbedtls_mpi *Rinv;    /* points to _Rinv (if not NULL) othwerwise &RR_new */
+    mbedtls_mpi_uint Mprime;
+
+    if (mbedtls_mpi_cmp_int(M, 0) <= 0 || (M->p[0] & 1) == 0) {
+        return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    }
+
+    if (mbedtls_mpi_cmp_int(Y, 0) < 0) {
+        return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    }
+
+    if (mbedtls_mpi_cmp_int(Y, 0) == 0) {
+        return mbedtls_mpi_lset(Z, 1);
+    }
+
+    if (num_words * 32 > SOC_RSA_MAX_BIT_LEN) {
+        return MBEDTLS_ERR_MPI_NOT_ACCEPTABLE;
+    }
+
+    /* Determine RR pointer, either _RR for cached value
+       or local RR_new */
+    if (_Rinv == NULL) {
+        mbedtls_mpi_init(&Rinv_new);
+        Rinv = &Rinv_new;
+    } else {
+        Rinv = _Rinv;
+    }
+    if (Rinv->p == NULL) {
+        MBEDTLS_MPI_CHK(calculate_rinv(Rinv, M, num_words));
+    }
+
+    Mprime = modular_inverse(M);
+
+    // Montgomery exponentiation: Z = X ^ Y mod M  (HAC 14.94)
+#ifdef ESP_MPI_USE_MONT_EXP
+    ret = mpi_montgomery_exp_calc(Z, X, Y, M, Rinv, num_words, Mprime) ;
+    MBEDTLS_MPI_CHK(ret);
+#else
+    esp_mpi_enable_hardware_hw_op();
+
+    esp_mpi_exp_mpi_mod_hw_op(X, Y, M, Rinv, Mprime, num_words);
+    ret = mbedtls_mpi_grow(Z, m_words);
+    if (ret != 0) {
+        esp_mpi_disable_hardware_hw_op();
+        goto cleanup;
+    }
+    esp_mpi_read_result_hw_op(Z, m_words);
+    esp_mpi_disable_hardware_hw_op();
+#endif
+
+    // Compensate for negative X
+    if (X->s == -1 && (Y->p[0] & 1) != 0) {
+        Z->s = -1;
+        MBEDTLS_MPI_CHK(mbedtls_mpi_add_mpi(Z, M, Z));
+    } else {
+        Z->s = 1;
+    }
+
+cleanup:
+    if (_Rinv == NULL) {
+        mbedtls_mpi_free(&Rinv_new);
+    }
+    return ret;
+}
+#endif //CONFIG_IDF_TARGET_ESP32C3
+
 
 
 #if defined(MBEDTLS_MPI_MUL_MPI_ALT) /* MBEDTLS_MPI_MUL_MPI_ALT */