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diff --git a/lib/bt/common/tinycrypt/src/ecc_dsa.c b/lib/bt/common/tinycrypt/src/ecc_dsa.c
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+++ b/lib/bt/common/tinycrypt/src/ecc_dsa.c
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+/*
+ * SPDX-FileCopyrightText: 2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/* Copyright (c) 2014, Kenneth MacKay
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.*/
+
+/*
+ *  Copyright (C) 2017 by Intel Corporation, All Rights Reserved.
+ *
+ *  Redistribution and use in source and binary forms, with or without
+ *  modification, are permitted provided that the following conditions are met:
+ *
+ *    - Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *
+ *    - Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ *    - Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *  POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <tinycrypt/constants.h>
+#include <tinycrypt/ecc.h>
+#include <tinycrypt/ecc_dsa.h>
+
+#if default_RNG_defined
+static uECC_RNG_Function g_rng_function = &default_CSPRNG;
+#else
+static uECC_RNG_Function g_rng_function = 0;
+#endif
+
+static void bits2int(uECC_word_t *native, const uint8_t *bits,
+		     unsigned bits_size, uECC_Curve curve)
+{
+	unsigned num_n_bytes = BITS_TO_BYTES(curve->num_n_bits);
+	unsigned num_n_words = BITS_TO_WORDS(curve->num_n_bits);
+	int shift;
+	uECC_word_t carry;
+	uECC_word_t *ptr;
+
+	if (bits_size > num_n_bytes) {
+		bits_size = num_n_bytes;
+	}
+
+	uECC_vli_clear(native, num_n_words);
+	uECC_vli_bytesToNative(native, bits, bits_size);
+	if (bits_size * 8 <= (unsigned)curve->num_n_bits) {
+		return;
+	}
+	shift = bits_size * 8 - curve->num_n_bits;
+	carry = 0;
+	ptr = native + num_n_words;
+	while (ptr-- > native) {
+		uECC_word_t temp = *ptr;
+		*ptr = (temp >> shift) | carry;
+		carry = temp << (uECC_WORD_BITS - shift);
+	}
+
+	/* Reduce mod curve_n */
+	if (uECC_vli_cmp_unsafe(curve->n, native, num_n_words) != 1) {
+		uECC_vli_sub(native, native, curve->n, num_n_words);
+	}
+}
+
+int uECC_sign_with_k(const uint8_t *private_key, const uint8_t *message_hash,
+		     unsigned hash_size, uECC_word_t *k, uint8_t *signature,
+		     uECC_Curve curve)
+{
+
+	uECC_word_t tmp[NUM_ECC_WORDS];
+	uECC_word_t s[NUM_ECC_WORDS];
+	uECC_word_t *k2[2] = {tmp, s};
+	uECC_word_t p[NUM_ECC_WORDS * 2];
+	uECC_word_t carry;
+	wordcount_t num_words = curve->num_words;
+	wordcount_t num_n_words = BITS_TO_WORDS(curve->num_n_bits);
+	bitcount_t num_n_bits = curve->num_n_bits;
+
+	/* Make sure 0 < k < curve_n */
+  	if (uECC_vli_isZero(k, num_words) ||
+	    uECC_vli_cmp(curve->n, k, num_n_words) != 1) {
+		return 0;
+	}
+
+	carry = regularize_k(k, tmp, s, curve);
+	EccPoint_mult(p, curve->G, k2[!carry], 0, num_n_bits + 1, curve);
+	if (uECC_vli_isZero(p, num_words)) {
+		return 0;
+	}
+
+	/* If an RNG function was specified, get a random number
+	to prevent side channel analysis of k. */
+	if (!g_rng_function) {
+		uECC_vli_clear(tmp, num_n_words);
+		tmp[0] = 1;
+	}
+	else if (!uECC_generate_random_int(tmp, curve->n, num_n_words)) {
+		return 0;
+	}
+
+	/* Prevent side channel analysis of uECC_vli_modInv() to determine
+	bits of k / the private key by premultiplying by a random number */
+	uECC_vli_modMult(k, k, tmp, curve->n, num_n_words); /* k' = rand * k */
+	uECC_vli_modInv(k, k, curve->n, num_n_words);       /* k = 1 / k' */
+	uECC_vli_modMult(k, k, tmp, curve->n, num_n_words); /* k = 1 / k */
+
+	uECC_vli_nativeToBytes(signature, curve->num_bytes, p); /* store r */
+
+	/* tmp = d: */
+	uECC_vli_bytesToNative(tmp, private_key, BITS_TO_BYTES(curve->num_n_bits));
+
+	s[num_n_words - 1] = 0;
+	uECC_vli_set(s, p, num_words);
+	uECC_vli_modMult(s, tmp, s, curve->n, num_n_words); /* s = r*d */
+
+	bits2int(tmp, message_hash, hash_size, curve);
+	uECC_vli_modAdd(s, tmp, s, curve->n, num_n_words); /* s = e + r*d */
+	uECC_vli_modMult(s, s, k, curve->n, num_n_words);  /* s = (e + r*d) / k */
+	if (uECC_vli_numBits(s, num_n_words) > (bitcount_t)curve->num_bytes * 8) {
+		return 0;
+	}
+
+	uECC_vli_nativeToBytes(signature + curve->num_bytes, curve->num_bytes, s);
+	return 1;
+}
+
+int uECC_sign(const uint8_t *private_key, const uint8_t *message_hash,
+	      unsigned hash_size, uint8_t *signature, uECC_Curve curve)
+{
+	      uECC_word_t _random[2*NUM_ECC_WORDS];
+	      uECC_word_t k[NUM_ECC_WORDS];
+	      uECC_word_t tries;
+
+	for (tries = 0; tries < uECC_RNG_MAX_TRIES; ++tries) {
+		/* Generating _random uniformly at random: */
+		uECC_RNG_Function rng_function = uECC_get_rng();
+		if (!rng_function ||
+		    !rng_function((uint8_t *)_random, 2*NUM_ECC_WORDS*uECC_WORD_SIZE)) {
+			return 0;
+		}
+
+		// computing k as modular reduction of _random (see FIPS 186.4 B.5.1):
+		uECC_vli_mmod(k, _random, curve->n, BITS_TO_WORDS(curve->num_n_bits));
+
+		if (uECC_sign_with_k(private_key, message_hash, hash_size, k, signature,
+		    curve)) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static bitcount_t smax(bitcount_t a, bitcount_t b)
+{
+	return (a > b ? a : b);
+}
+
+int uECC_verify(const uint8_t *public_key, const uint8_t *message_hash,
+		unsigned hash_size, const uint8_t *signature,
+	        uECC_Curve curve)
+{
+
+	uECC_word_t u1[NUM_ECC_WORDS], u2[NUM_ECC_WORDS];
+	uECC_word_t z[NUM_ECC_WORDS];
+	uECC_word_t sum[NUM_ECC_WORDS * 2];
+	uECC_word_t rx[NUM_ECC_WORDS];
+	uECC_word_t ry[NUM_ECC_WORDS];
+	uECC_word_t tx[NUM_ECC_WORDS];
+	uECC_word_t ty[NUM_ECC_WORDS];
+	uECC_word_t tz[NUM_ECC_WORDS];
+	const uECC_word_t *points[4];
+	const uECC_word_t *point;
+	bitcount_t num_bits;
+	bitcount_t i;
+
+	uECC_word_t _public[NUM_ECC_WORDS * 2];
+	uECC_word_t r[NUM_ECC_WORDS], s[NUM_ECC_WORDS];
+	wordcount_t num_words = curve->num_words;
+	wordcount_t num_n_words = BITS_TO_WORDS(curve->num_n_bits);
+
+	rx[num_n_words - 1] = 0;
+	r[num_n_words - 1] = 0;
+	s[num_n_words - 1] = 0;
+
+	uECC_vli_bytesToNative(_public, public_key, curve->num_bytes);
+	uECC_vli_bytesToNative(_public + num_words, public_key + curve->num_bytes,
+			       curve->num_bytes);
+	uECC_vli_bytesToNative(r, signature, curve->num_bytes);
+	uECC_vli_bytesToNative(s, signature + curve->num_bytes, curve->num_bytes);
+
+	/* r, s must not be 0. */
+	if (uECC_vli_isZero(r, num_words) || uECC_vli_isZero(s, num_words)) {
+		return 0;
+	}
+
+	/* r, s must be < n. */
+	if (uECC_vli_cmp_unsafe(curve->n, r, num_n_words) != 1 ||
+	    uECC_vli_cmp_unsafe(curve->n, s, num_n_words) != 1) {
+		return 0;
+	}
+
+	/* Calculate u1 and u2. */
+	uECC_vli_modInv(z, s, curve->n, num_n_words); /* z = 1/s */
+	u1[num_n_words - 1] = 0;
+	bits2int(u1, message_hash, hash_size, curve);
+	uECC_vli_modMult(u1, u1, z, curve->n, num_n_words); /* u1 = e/s */
+	uECC_vli_modMult(u2, r, z, curve->n, num_n_words); /* u2 = r/s */
+
+	/* Calculate sum = G + Q. */
+	uECC_vli_set(sum, _public, num_words);
+	uECC_vli_set(sum + num_words, _public + num_words, num_words);
+	uECC_vli_set(tx, curve->G, num_words);
+	uECC_vli_set(ty, curve->G + num_words, num_words);
+	uECC_vli_modSub(z, sum, tx, curve->p, num_words); /* z = x2 - x1 */
+	XYcZ_add(tx, ty, sum, sum + num_words, curve);
+	uECC_vli_modInv(z, z, curve->p, num_words); /* z = 1/z */
+	apply_z(sum, sum + num_words, z, curve);
+
+	/* Use Shamir's trick to calculate u1*G + u2*Q */
+	points[0] = 0;
+	points[1] = curve->G;
+	points[2] = _public;
+	points[3] = sum;
+	num_bits = smax(uECC_vli_numBits(u1, num_n_words),
+	uECC_vli_numBits(u2, num_n_words));
+
+	point = points[(!!uECC_vli_testBit(u1, num_bits - 1)) |
+                       ((!!uECC_vli_testBit(u2, num_bits - 1)) << 1)];
+	uECC_vli_set(rx, point, num_words);
+	uECC_vli_set(ry, point + num_words, num_words);
+	uECC_vli_clear(z, num_words);
+	z[0] = 1;
+
+	for (i = num_bits - 2; i >= 0; --i) {
+		uECC_word_t index;
+		curve->double_jacobian(rx, ry, z, curve);
+
+		index = (!!uECC_vli_testBit(u1, i)) | ((!!uECC_vli_testBit(u2, i)) << 1);
+		point = points[index];
+		if (point) {
+			uECC_vli_set(tx, point, num_words);
+			uECC_vli_set(ty, point + num_words, num_words);
+			apply_z(tx, ty, z, curve);
+			uECC_vli_modSub(tz, rx, tx, curve->p, num_words); /* Z = x2 - x1 */
+			XYcZ_add(tx, ty, rx, ry, curve);
+			uECC_vli_modMult_fast(z, z, tz, curve);
+		}
+  	}
+
+	uECC_vli_modInv(z, z, curve->p, num_words); /* Z = 1/Z */
+	apply_z(rx, ry, z, curve);
+
+	/* v = x1 (mod n) */
+	if (uECC_vli_cmp_unsafe(curve->n, rx, num_n_words) != 1) {
+		uECC_vli_sub(rx, rx, curve->n, num_n_words);
+	}
+
+	/* Accept only if v == r. */
+	return (int)(uECC_vli_equal(rx, r, num_words) == 0);
+}