cryptocb: add WC_ALGO_TYPE_KEYSTORE for hardware key store operations

.skoll-known.md

@@ -0,0 +1,14 @@
+# Known issues
+
+Findings already investigated and closed. A scan that raises one of these again is re-reporting settled work; check the code before acting on it.
+
+## EdgeLock (els_pkc) port
+
+- **ECDSA sign/verify stack overflow for digests over 80 bytes.** Not present. Both guards are `inlen > 255 || inlen > sizeof(hash)` (and `hashLen` likewise); the buffer bound is the second half of the condition, and reading only the first half suggests an overflow that cannot happen. `ElsPkcEccSign` and `ElsPkcEccVerify` in `wolfcrypt/src/port/nxp/els_pkc_port.c`, covered by the "oversized digest does not overflow the port buffer" check in the Zephyr sample.
+- **`ElsRandom` violating the ELS DRBG word-multiple contract.** Handled deliberately: the whole-word part is generated into the caller's buffer and the remainder comes from a word-sized scratch, because declining would fail the call rather than fall back. Sizes 1 through 33 are exercised in the sample.
+- **`ElsSha256Copy` leaking the destination's `msg` and `W` buffers.** Closed: `wc_Sha256Free(dst)` runs before the struct copy, for exactly this reason.
+- **`ElsEccKeyGen` not validating the slot with `ElsCheckSlot()`.** By design. On a key generation the reference is a request rather than a lookup: the slot is empty and the key does not exist until the call returns, so a check requiring an active key would reject every valid keygen.
+- **`wc_ElsPkc_HashOffloadCount` overstating the offload.** Fixed 2026-09-01; it now increments only after `ElsWait()` succeeds, so it counts engine runs rather than accepted updates.
+- **No HMAC arm in the dispatch table.** Deliberate. The ELS HMAC command is one-shot while wolfCrypt drives HMAC incrementally, so an arm would have to buffer whole messages. HMAC is accelerated anyway because the inner hash inherits the devId.
+- **RSA encrypt/decrypt (OAEP) declined.** Blocked upstream: every `MCUXCLRSA_ENCRYPT_*` and `_DECRYPT_*` workarea macro in NXP's `mcuxClRsa_MemoryConsumption.h` for rw61x is an unsubstituted `$(...)` template placeholder and will not compile.
+- **AES-192, Ed448, deterministic ECDSA, SHA-1/SHA-3, AES-CCM/XTS/CFB/OFB declined.** The hardware has no such capability; each decline sits next to a comment saying so.

CMakeLists.txt

@@ -4546,6 +4546,7 @@ if(WOLFSSL_EXAMPLES)
         tests/api/test_hpke.c
         tests/api/test_kdf.c
         tests/api/test_she.c
+        tests/api/test_keystore.c
         tests/api/test_async.c
         tests/api/test_des3.c
         tests/api/test_chacha.c

cmake/functions.cmake

@@ -1296,6 +1296,9 @@ function(generate_lib_src_list LIB_SOURCES)
     # Corresponds to wolfcrypt/src/include.am
     if(BUILD_CRYPTOCB)
         list(APPEND LIB_SOURCES wolfcrypt/src/cryptocb.c)
+        # entirely #ifdef WOLF_CRYPTO_CB_KEYSTORE, so it costs nothing when the
+        # key store facility is not enabled
+        list(APPEND LIB_SOURCES wolfcrypt/src/wc_keystore.c)
     endif()
 
     if(BUILD_SHE)

configure.ac

@@ -11744,7 +11744,7 @@ fi
 
 # Crypto Callbacks Utils (Copy/Free/etc)
 AC_ARG_ENABLE([cryptocbutils],
-    [AS_HELP_STRING([--enable-cryptocbutils@<:@=copy,free,setkey,export,...@:>@],
+    [AS_HELP_STRING([--enable-cryptocbutils@<:@=copy,free,setkey,export,keystore,...@:>@],
                     [Enable crypto callback utilities (default: all)])],
     [ ENABLED_CRYPTOCB_UTILS=$enableval ],
     [ ENABLED_CRYPTOCB_UTILS=no ]
@@ -11757,7 +11757,7 @@ if test "$ENABLED_CRYPTOCB_UTILS" != "no"; then
 
     if test "$ENABLED_CRYPTOCB_UTILS" = "yes"; then
         # Enable all utilities
-        AM_CFLAGS="$AM_CFLAGS -DWOLF_CRYPTO_CB_COPY -DWOLF_CRYPTO_CB_FREE -DWOLF_CRYPTO_CB_SETKEY -DWOLF_CRYPTO_CB_EXPORT_KEY"
+        AM_CFLAGS="$AM_CFLAGS -DWOLF_CRYPTO_CB_COPY -DWOLF_CRYPTO_CB_FREE -DWOLF_CRYPTO_CB_SETKEY -DWOLF_CRYPTO_CB_EXPORT_KEY -DWOLF_CRYPTO_CB_KEYSTORE"
     else
         # Parse comma-separated list
         OIFS="$IFS"
@@ -11776,8 +11776,11 @@ if test "$ENABLED_CRYPTOCB_UTILS" != "no"; then
                 export)
                     AM_CFLAGS="$AM_CFLAGS -DWOLF_CRYPTO_CB_EXPORT_KEY"
                     ;;
+                keystore)
+                    AM_CFLAGS="$AM_CFLAGS -DWOLF_CRYPTO_CB_KEYSTORE"
+                    ;;
                 *)
-                    AC_MSG_ERROR([Unknown cryptocbutils option: $util. Valid options: copy, free, setkey, export])
+                    AC_MSG_ERROR([Unknown cryptocbutils option: $util. Valid options: copy, free, setkey, export, keystore])
                     ;;
             esac
         done