CVPN-1554 Use WolfSSL private key patch

Use the official fix from WolfSSL PR: wolfSSL/wolfssl#8196 instead of our own implementation to enable private key fields in key share entry when we are using post-quantum KEM.

Author: kp-thomas-yau

wolfssl-sys/build.rs

@@ -44,7 +44,7 @@ fn copy_wolfssl(dest: &Path) -> std::io::Result<PathBuf> {
 
 const PATCH_DIR: &str = "patches";
 const PATCHES: &[&str] = &[
-    "disable-falcon-dilithium.patch",
+    "include-private-key-fields-for-kyber.patch",
     "make-kyber-mlkem-available.patch",
     "fix-kyber-mlkem-benchmark.patch",
     "fix-mlkem-get-curve-name.patch",

wolfssl-sys/patches/disable-falcon-dilithium.patch

@@ -0,0 +1,24 @@
+From 5d61ca94c05561aefb11dfab4e15682c249c3746 Mon Sep 17 00:00:00 2001
+From: Sean Parkinson <[email protected]>
+Date: Mon, 18 Nov 2024 08:29:16 +1000
+Subject: [PATCH] KeyShareEntry: include private key fields for KYBER
+
+Originallt HAVE_PQC and then changed to HAVE_FALCON and HAVE_DILITHIUM.
+The KEM PQC algorithm is actually KYBER.
+---
+ wolfssl/internal.h | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/wolfssl/internal.h b/wolfssl/internal.h
+index 70c99818e5..2519f09d8c 100644
+--- a/wolfssl/internal.h
++++ b/wolfssl/internal.h
+@@ -3539,7 +3539,7 @@ typedef struct KeyShareEntry {
+     word32                keyLen;    /* Key size (bytes)                  */
+     byte*                 pubKey;    /* Public key                        */
+     word32                pubKeyLen; /* Public key length                 */
+-#if !defined(NO_DH) || defined(HAVE_FALCON) || defined(HAVE_DILITHIUM)
++#if !defined(NO_DH) || defined(WOLFSSL_HAVE_KYBER)
+     byte*                 privKey;   /* Private key - DH and PQ KEMs only */
+     word32                privKeyLen;/* Only for PQ KEMs. */
+ #endif