From 293719c16850aa5bfc98587e615095f4da520262 Mon Sep 17 00:00:00 2001
From: Marco Oliverio <marco@wolfssl.com>
Date: Mon, 2 Sep 2024 15:25:53 +0000
Subject: [PATCH 1/2] ocsp: search CA by key hash instead of ext key id

---
 src/ssl.c           | 30 ++++++++++++++++++++++++++++++
 wolfcrypt/src/asn.c |  4 ++--
 wolfssl/internal.h  |  3 +++
 3 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/src/ssl.c b/src/ssl.c
index b4bf40744..2940215e8 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -5102,6 +5102,36 @@ Signer* GetCA(void* vp, byte* hash)
     return ret;
 }
 
+#if defined(HAVE_OCSP)
+Signer* GetCAByKeyHash(void* vp, const byte* keyHash)
+{
+    WOLFSSL_CERT_MANAGER* cm = (WOLFSSL_CERT_MANAGER*)vp;
+    Signer* ret = NULL;
+    Signer* signers;
+    int row;
+
+    if (cm == NULL || keyHash == NULL)
+        return NULL;
+
+    if (wc_LockMutex(&cm->caLock) != 0)
+        return NULL;
+
+    /* Unfortunately we need to look through the entire table */
+    for (row = 0; row < CA_TABLE_SIZE && ret == NULL; row++) {
+        for (signers = cm->caTable[row]; signers != NULL;
+                signers = signers->next) {
+            if (XMEMCMP(signers->subjectKeyHash, keyHash, KEYID_SIZE)
+                    == 0) {
+                ret = signers;
+                break;
+            }
+        }
+    }
+
+    wc_UnLockMutex(&cm->caLock);
+    return ret;
+}
+#endif
 #ifdef WOLFSSL_AKID_NAME
 Signer* GetCAByAKID(void* vp, const byte* issuer, word32 issuerSz,
         const byte* serial, word32 serialSz)
diff --git a/wolfcrypt/src/asn.c b/wolfcrypt/src/asn.c
index 06dfa0df5..431b833d7 100644
--- a/wolfcrypt/src/asn.c
+++ b/wolfcrypt/src/asn.c
@@ -36770,7 +36770,7 @@ static int DecodeBasicOcspResponse(byte* source, word32* ioIndex,
         int sigValid = -1;
 
         #ifndef NO_SKID
-            ca = GetCA(cm, resp->single->issuerKeyHash);
+            ca = GetCAByKeyHash(cm, resp->single->issuerKeyHash);
         #else
             ca = GetCA(cm, resp->single->issuerHash);
         #endif
@@ -36911,7 +36911,7 @@ static int DecodeBasicOcspResponse(byte* source, word32* ioIndex,
 
         /* Response didn't have a certificate - lookup CA. */
     #ifndef NO_SKID
-        ca = GetCA(cm, resp->single->issuerKeyHash);
+        ca = GetCAByKeyHash(cm, resp->single->issuerKeyHash);
     #else
         ca = GetCA(cm, resp->single->issuerHash);
     #endif
diff --git a/wolfssl/internal.h b/wolfssl/internal.h
index 9e57ab0c4..b5f643574 100644
--- a/wolfssl/internal.h
+++ b/wolfssl/internal.h
@@ -6460,6 +6460,9 @@ WOLFSSL_LOCAL WC_RNG* WOLFSSL_RSA_GetRNG(WOLFSSL_RSA *rsa, WC_RNG **tmpRNG,
         WOLFSSL_LOCAL Signer* GetCAByAKID(void* vp, const byte* issuer,
                 word32 issuerSz, const byte* serial, word32 serialSz);
     #endif
+    #ifdef HAVE_OCSP
+        WOLFSSL_LOCAL Signer* GetCAByKeyHash(void* vp, const byte* keyHash);
+    #endif
     #if !defined(NO_SKID) && !defined(GetCAByName)
         WOLFSSL_LOCAL Signer* GetCAByName(void* cm, byte* hash);
     #endif

From 6114691fd6ff22e5b3635209cec284292fc95468 Mon Sep 17 00:00:00 2001
From: Marco Oliverio <marco@wolfssl.com>
Date: Thu, 5 Sep 2024 09:49:01 +0000
Subject: [PATCH 2/2] ocsp: try lookup certificate using keyHash as KeyId

try to lookup the certificate using the key hash as key identifier
first. If we can't find a certificate, it means that the certificate
uses another method to compute the key identifier so we need to fallback
to linear search.
---
 src/ssl.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/ssl.c b/src/ssl.c
index 2940215e8..37e5ce065 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -5113,6 +5113,13 @@ Signer* GetCAByKeyHash(void* vp, const byte* keyHash)
     if (cm == NULL || keyHash == NULL)
         return NULL;
 
+    /* try lookup using keyHash as subjKeyID first */
+    ret = GetCA(vp, (byte*)keyHash);
+    if (ret != NULL && XMEMCMP(ret->subjectKeyHash, keyHash, KEYID_SIZE) == 0) {
+        return ret;
+    }
+
+    /* if we can't find the cert, we have to scan the full table */
     if (wc_LockMutex(&cm->caLock) != 0)
         return NULL;
 
@@ -5120,8 +5127,7 @@ Signer* GetCAByKeyHash(void* vp, const byte* keyHash)
     for (row = 0; row < CA_TABLE_SIZE && ret == NULL; row++) {
         for (signers = cm->caTable[row]; signers != NULL;
                 signers = signers->next) {
-            if (XMEMCMP(signers->subjectKeyHash, keyHash, KEYID_SIZE)
-                    == 0) {
+            if (XMEMCMP(signers->subjectKeyHash, keyHash, KEYID_SIZE) == 0) {
                 ret = signers;
                 break;
             }