From f4d2dc2d772cef1baa7367996c45e9a0ae7e1be1 Mon Sep 17 00:00:00 2001
From: Valerio Setti <valerio.setti@nordicsemi.no>
Date: Tue, 16 Jan 2024 10:57:48 +0100
Subject: [PATCH] psa_util: guard ECDSA conversion functions with proper
 (internal) symbol

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
---
 include/mbedtls/config_adjust_legacy_crypto.h    | 7 +++++++
 include/mbedtls/psa_util.h                       | 4 ++++
 library/psa_util.c                               | 4 ++++
 tests/suites/test_suite_psa_crypto_util.function | 4 ++--
 4 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/include/mbedtls/config_adjust_legacy_crypto.h b/include/mbedtls/config_adjust_legacy_crypto.h
index 696266c6f..833f15268 100644
--- a/include/mbedtls/config_adjust_legacy_crypto.h
+++ b/include/mbedtls/config_adjust_legacy_crypto.h
@@ -400,6 +400,13 @@
 #define MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_ONLY
 #endif
 
+/* psa_util file features some ECDSA conversion functions, to convert between
+ * legacy's ASN.1 DER format and PSA's raw one. */
+#if defined(MBEDTLS_ECDSA_C) || defined(MBEDTLS_PSA_CRYPTO_C) && \
+    (defined(PSA_WANT_ALG_ECDSA) || defined(PSA_WANT_ALG_DETERMINISTIC_ECDSA))
+#define MBEDTLS_PSA_UTIL_HAVE_ECDSA
+#endif
+
 /* Some internal helpers to determine which keys are availble. */
 #if (!defined(MBEDTLS_USE_PSA_CRYPTO) && defined(MBEDTLS_AES_C)) || \
     (defined(MBEDTLS_USE_PSA_CRYPTO) && defined(PSA_WANT_KEY_TYPE_AES))
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
index 93fb38d73..3bf05d183 100644
--- a/include/mbedtls/psa_util.h
+++ b/include/mbedtls/psa_util.h
@@ -182,6 +182,8 @@ static inline mbedtls_md_type_t mbedtls_md_type_from_psa_alg(psa_algorithm_t psa
 }
 #endif /* MBEDTLS_PSA_CRYPTO_C */
 
+#if defined(MBEDTLS_PSA_UTIL_HAVE_ECDSA)
+
 #if defined(MBEDTLS_ASN1_WRITE_C)
 /** Convert an ECDSA signature from raw format (used by PSA APIs) to DER ASN.1
  * format (used by legacy crypto APIs).
@@ -220,6 +222,8 @@ int mbedtls_ecdsa_der_to_raw(const unsigned char *der, size_t der_len,
                              size_t bits);
 #endif /* MBEDTLS_ASN1_PARSE_C */
 
+#endif /* MBEDTLS_PSA_UTIL_HAVE_ECDSA */
+
 /**@}*/
 
 #endif /* MBEDTLS_PSA_UTIL_H */
diff --git a/library/psa_util.c b/library/psa_util.c
index ef9aff172..c78b6035d 100644
--- a/library/psa_util.c
+++ b/library/psa_util.c
@@ -338,6 +338,8 @@ mbedtls_ecp_group_id mbedtls_ecc_group_from_psa(psa_ecc_family_t family,
 
 #endif /* MBEDTLS_PSA_CRYPTO_C */
 
+#if defined(MBEDTLS_PSA_UTIL_HAVE_ECDSA)
+
 #if defined(MBEDTLS_ASN1_WRITE_C)
 /**
  * \brief  Convert a single raw coordinate to DER ASN.1 format. The output der
@@ -569,3 +571,5 @@ int mbedtls_ecdsa_der_to_raw(const unsigned char *der, size_t der_len,
     return 0;
 }
 #endif /* MBEDTLS_ASN1_PARSE_C */
+
+#endif /* MBEDTLS_PSA_UTIL_HAVE_ECDSA */
diff --git a/tests/suites/test_suite_psa_crypto_util.function b/tests/suites/test_suite_psa_crypto_util.function
index 3c4976607..bfdafa7b3 100644
--- a/tests/suites/test_suite_psa_crypto_util.function
+++ b/tests/suites/test_suite_psa_crypto_util.function
@@ -3,7 +3,7 @@
 #include <mbedtls/psa_util.h>
 /* END_HEADER */
 
-/* BEGIN_CASE depends_on:MBEDTLS_ASN1_WRITE_C */
+/* BEGIN_CASE depends_on:MBEDTLS_PSA_UTIL_HAVE_ECDSA:MBEDTLS_ASN1_WRITE_C */
 void ecdsa_raw_to_der(int key_bits, data_t *input, data_t *exp_result, int exp_ret)
 {
     unsigned char *tmp_buf = NULL;
@@ -25,7 +25,7 @@ exit:
 }
 /* END_CASE */
 
-/* BEGIN_CASE depends_on:MBEDTLS_ASN1_PARSE_C */
+/* BEGIN_CASE depends_on:MBEDTLS_PSA_UTIL_HAVE_ECDSA:MBEDTLS_ASN1_PARSE_C */
 void ecdsa_der_to_raw(int key_bits, data_t *input, data_t *exp_result, int exp_ret)
 {
     unsigned char *tmp_buf = NULL;