From 2d5bc72c9bd5e74f35b3deb68b39f7b92e8d7adf Mon Sep 17 00:00:00 2001
From: David Garske <david@wolfssl.com>
Date: Wed, 13 Jul 2022 16:17:08 -0700
Subject: [PATCH] Fixes for ED25519/ED448 private key with public key export
 (RFC8410). Added length only support.

---
 tests/api.c         | 60 ++++++++++++++++++++++++---------------------
 wolfcrypt/src/asn.c | 21 +++++++++-------
 2 files changed, 44 insertions(+), 37 deletions(-)

diff --git a/tests/api.c b/tests/api.c
index a055befe4..67177f8a6 100644
--- a/tests/api.c
+++ b/tests/api.c
@@ -26646,19 +26646,20 @@ static int test_wc_Ed25519KeyToDer (void)
                 ret = 0;
             }
         }
-        if (ret == 0) {
-            ret = wc_Ed25519KeyToDer(&ed25519Key, NULL, inLen);
-            if (ret == BAD_FUNC_ARG) {
-                ret = 0;
-            }
-        }
         if (ret == 0) {
             ret = wc_Ed25519KeyToDer(&ed25519Key, output, 0);
             if (ret == BAD_FUNC_ARG) {
                 ret = 0;
             }
         }
-        /* Good Case */
+        /* Good Cases */
+        if (ret == 0) {
+            /* length only */
+            ret = wc_Ed25519KeyToDer(&ed25519Key, NULL, inLen);
+            if (ret > 0) {
+                ret = 0;
+            }
+        }
         if (ret == 0) {
             ret = wc_Ed25519KeyToDer(&ed25519Key, output, inLen);
             if (ret > 0) {
@@ -26713,19 +26714,20 @@ static int test_wc_Ed25519PrivateKeyToDer (void)
                 ret = 0;
             }
         }
-        if (ret == 0) {
-            ret = wc_Ed25519PrivateKeyToDer(&ed25519PrivKey, NULL, inLen);
-            if (ret == BAD_FUNC_ARG) {
-                ret = 0;
-            }
-        }
         if (ret == 0) {
             ret = wc_Ed25519PrivateKeyToDer(&ed25519PrivKey, output, 0);
             if (ret == BAD_FUNC_ARG) {
                 ret = 0;
             }
         }
-        /* Good Case */
+        /* Good Cases */
+        if (ret == 0) {
+            /* length only */
+            ret = wc_Ed25519PrivateKeyToDer(&ed25519PrivKey, NULL, inLen);
+            if (ret > 0) {
+                ret = 0;
+            }
+        }
         if (ret == 0) {
             ret = wc_Ed25519PrivateKeyToDer(&ed25519PrivKey, output, inLen);
             if (ret > 0) {
@@ -26779,19 +26781,20 @@ static int test_wc_Ed448KeyToDer (void)
                 ret = 0;
             }
         }
-        if (ret == 0) {
-            ret = wc_Ed448KeyToDer(&ed448Key, NULL, inLen);
-            if (ret == BAD_FUNC_ARG) {
-                ret = 0;
-            }
-        }
         if (ret == 0) {
             ret = wc_Ed448KeyToDer(&ed448Key, output, 0);
             if (ret == BAD_FUNC_ARG) {
                 ret = 0;
             }
         }
-        /* Good Case */
+        /* Good Cases */
+        if (ret == 0) {
+            /* length only */
+            ret = wc_Ed448KeyToDer(&ed448Key, NULL, inLen);
+            if (ret > 0) {
+                ret = 0;
+            }
+        }
         if (ret == 0) {
             ret = wc_Ed448KeyToDer(&ed448Key, output, inLen);
             if (ret > 0) {
@@ -26845,19 +26848,20 @@ static int test_wc_Ed448PrivateKeyToDer (void)
                 ret = 0;
             }
         }
-        if (ret == 0) {
-            ret = wc_Ed448PrivateKeyToDer(&ed448PrivKey, NULL, inLen);
-            if (ret == BAD_FUNC_ARG) {
-                ret = 0;
-            }
-        }
         if (ret == 0) {
             ret = wc_Ed448PrivateKeyToDer(&ed448PrivKey, output, 0);
             if (ret == BAD_FUNC_ARG) {
                 ret = 0;
             }
         }
-        /* Good case */
+        /* Good cases */
+        if (ret == 0) {
+            /* length only */
+            ret = wc_Ed448PrivateKeyToDer(&ed448PrivKey, NULL, inLen);
+            if (ret > 0) {
+                ret = 0;
+            }
+        }
         if (ret == 0) {
             ret = wc_Ed448PrivateKeyToDer(&ed448PrivKey, output, inLen);
             if (ret > 0) {
diff --git a/wolfcrypt/src/asn.c b/wolfcrypt/src/asn.c
index 1f3380b73..d0dd3973c 100644
--- a/wolfcrypt/src/asn.c
+++ b/wolfcrypt/src/asn.c
@@ -29755,7 +29755,7 @@ static int DecodeAsymKey(const byte* input, word32* inOutIdx, word32 inSz,
             return BAD_FUNC_ARG;
         }
 
-        if (GetASNHeader(input, ASN_CONTEXT_SPECIFIC | ASN_CONSTRUCTED | 1,
+        if (GetASNHeader(input, ASN_CONTEXT_SPECIFIC | ASN_ASYMKEY_PUBKEY | 1,
                          inOutIdx, &length, inSz) < 0) {
             return ASN_PARSE_E;
         }
@@ -30023,7 +30023,6 @@ int wc_Curve25519PublicKeyDecode(const byte* input, word32* inOutIdx,
  * @return  Size of encoded data in bytes on success
  * @return  BAD_FUNC_ARG when key is NULL.
  * @return  MEMORY_E when dynamic memory allocation failed.
- * @return  LENGTH_ONLY_E return length only.
  */
 static int SetAsymKeyDer(const byte* privKey, word32 privKeyLen,
     const byte* pubKey, word32 pubKeyLen,
@@ -30045,7 +30044,7 @@ static int SetAsymKeyDer(const byte* privKey, word32 privKeyLen,
 #ifndef WOLFSSL_ASN_TEMPLATE
     /* calculate size */
     if (pubKey) {
-        pubSz = 2 + 2 + pubKeyLen;
+        pubSz = 2 + pubKeyLen;
     }
     privSz = 2 + 2 + privKeyLen;
     algoSz = SetAlgoID(keyType, NULL, oidKeyType, 0);
@@ -30061,7 +30060,7 @@ static int SetAsymKeyDer(const byte* privKey, word32 privKeyLen,
     if (ret == 0 && output != NULL) {
         /* write out */
         /* seq */
-        seqSz  = SetSequence(verSz + algoSz + privSz + pubSz, output);
+        seqSz = SetSequence(verSz + algoSz + privSz + pubSz, output);
         idx = seqSz;
         /* ver */
         SetMyVersion(0, output + idx, FALSE);
@@ -30076,13 +30075,16 @@ static int SetAsymKeyDer(const byte* privKey, word32 privKeyLen,
         idx += privKeyLen;
         /* pubKey */
         if (pubKey) {
-            idx += SetExplicit(1, 2 + pubKeyLen, output + idx);
-            idx += SetOctetString(pubKeyLen, output + idx);
+            idx += SetHeader(ASN_CONTEXT_SPECIFIC | ASN_ASYMKEY_PUBKEY |
+                             1, pubKeyLen, output + idx);
             XMEMCPY(output + idx, pubKey, pubKeyLen);
             idx += pubKeyLen;
         }
-
-        ret = idx;
+        sz = idx;
+    }
+    if (ret == 0) {
+        /* Return size of encoding. */
+        ret = sz;
     }
 #else
 
@@ -30128,7 +30130,8 @@ static int SetAsymKeyDer(const byte* privKey, word32 privKeyLen,
             XMEMCPY((byte*)dataASN[EDKEYASN_IDX_PUBKEY_VAL].data.buffer.data,
                     pubKey, pubKeyLen);
         }
-
+    }
+    if (ret == 0) {
         /* Return size of encoding. */
         ret = sz;
     }