zephyr: crypto: fix DPP3 build error

Fix DPP3 build error for latest upmerge.
Add empty api hpke_base_seal and hpke_base_open,
which will be called by wpas_dpp_rx_priv_peer_intro_notify,
only when ssid_field option dpp_connector_privacy is enabled.
But in zephyr case we won't provide visible way of enablding
it to user.

But DPP3 carries other fixes except this function.
So this empty api is okay and can fix build error when DPP3 enabled.

Porting from original file to fix missing api build error,
https://github.com/gstrauss/hostap/blob/mbedtls/src/crypto/crypto_mbedtls.c.

Signed-off-by: Fengming Ye <[email protected]>

Author: fengming-ye

src/crypto/crypto_mbedtls_alt.c

@@ -138,6 +138,10 @@
 #define CRYPTO_MBEDTLS_CRYPTO_PKCS7
 #endif /* crypto_pkcs7_*() */
 
+#if defined(CONFIG_DPP3) /* CONFIG_DPP3=y */
+#define CRYPTO_MBEDTLS_CRYPTO_HPKE
+#endif
+
 #if defined(EAP_SIM) || defined(EAP_SIM_DYNAMIC) || defined(EAP_SERVER_SIM) || defined(EAP_AKA) || \
     defined(EAP_AKA_DYNAMIC) || defined(EAP_SERVER_AKA) || defined(CONFIG_AP) || defined(HOSTAPD)
 /* CONFIG_EAP_SIM=y CONFIG_EAP_AKA=y CONFIG_AP=y HOSTAPD */
@@ -3229,4 +3233,37 @@ struct wpabuf *crypto_pkcs7_get_certificates(const struct wpabuf *pkcs7)
 }
 #endif /* CRYPTO_MBEDTLS_CRYPTO_PKCS7 */
 
+#ifdef CRYPTO_MBEDTLS_CRYPTO_HPKE
+
+struct wpabuf *hpke_base_seal(enum hpke_kem_id kem_id,
+                              enum hpke_kdf_id kdf_id,
+                              enum hpke_aead_id aead_id,
+                              struct crypto_ec_key *peer_pub,
+                              const u8 *info,
+                              size_t info_len,
+                              const u8 *aad,
+                              size_t aad_len,
+                              const u8 *pt,
+                              size_t pt_len)
+{
+    /* not yet implemented */
+    return NULL;
+}
+
+struct wpabuf *hpke_base_open(enum hpke_kem_id kem_id,
+                              enum hpke_kdf_id kdf_id,
+                              enum hpke_aead_id aead_id,
+                              struct crypto_ec_key *own_priv,
+                              const u8 *info,
+                              size_t info_len,
+                              const u8 *aad,
+                              size_t aad_len,
+                              const u8 *enc_ct,
+                              size_t enc_ct_len)
+{
+    /* not yet implemented */
+    return NULL;
+}
+#endif
+
 #endif