Replace liboqs SPHINCS+ with SLH-DSA in certificate layer

Replace the liboqs-based pre-standardization SPHINCS+ implementation
with the native FIPS 205 SLH-DSA implementation across the
certificate / ASN.1 / X.509 layers, and add SLH-DSA-rooted test
certificates plus TLS 1.3 .conf scenarios that exercise the new
verification path. All liboqs SPHINCS+ code is removed.

This enables SLH-DSA for certificate chain authentication: CA
certificates signed with SLH-DSA, certificate signature verification
against an SLH-DSA root. TLS 1.3 entity authentication via
CertificateVerify with SLH-DSA will be added in a follow-up PR.

Follows RFC 9909 (X.509 Algorithm Identifiers for SLH-DSA) and
NIST FIPS 205. Supports both SHAKE and SHA-2 parameter families
across all twelve standardized variants.

DER codec:
- New PrivateKeyDecode, PublicKeyDecode, KeyToDer, PrivateKeyToDer,
  PublicKeyToDer with RFC 9909 encoding (bare OCTET STRING containing
  4*n raw bytes = SK.seed || SK.prf || PK.seed || PK.root, no nested
  wrapper). OID auto-detection across all twelve SHAKE / SHA-2 variants.
- PublicKeyDecode raw-bytes fast path mirrors wc_Falcon_PublicKeyDecode
  and wc_Dilithium_PublicKeyDecode so callers (notably
  wolfssl_x509_make_der and ConfirmSignature, which pass the raw
  BIT STRING contents stashed by StoreKey) decode correctly. Honours
  the caller's *inOutIdx start offset.
- Error paths in Private/PublicKeyDecode preserve params/flags/
  inOutIdx and only ForceZero the buffer half each helper actually
  writes; skip the wipe entirely on BAD_LENGTH_E (no bytes touched).
- ImportPublic uses |= on flags so a Private-then-Public import
  sequence retains FLAG_PRIVATE.

OID dispatch:
- 12 standardized NIST OIDs (6 SHAKE + 6 SHA-2) per RFC 9909. The
  pre-standardization OID-collision mechanism is removed since NIST
  OIDs do not collide.
- wc_SlhDsaOidToParam / wc_SlhDsaOidToCertType return NOT_COMPILED_IN
  (rather than -1) for recognised SLH-DSA OIDs whose parameter set
  isn't built; wc_IsSlhDsaOid recognises both. The x509 dispatch
  surfaces this as a precise diagnostic instead of the generic
  "No public key found".
- wc_GetKeyOID picks a placeholder parameter from whatever variant is
  compiled in and #errors at compile time if none is.
- asn_orig.c EncodeCert / EncodeCertReq accept SHA-2 SLH-DSA keyTypes
  alongside SHAKE.

Tests and fixtures:
- Test cert chain in certs/slhdsa/: SLH-DSA-SHAKE-128s and
  SLH-DSA-SHA2-128s self-signed roots that sign reused ML-DSA-44
  entity keys (server + client), plus the gen script
  (gen-slhdsa-mldsa-certs.sh, OpenSSL >= 3.5).
- New TLS 1.3 .conf scenarios under tests/suites.c dispatch:
  test-tls13-slhdsa-shake.conf, test-tls13-slhdsa-sha2.conf, and a
  wrong-CA negative test test-tls13-slhdsa-fail.conf.
- DER round-trip and on-disk decode tests; bench_slhdsa_*_key.der
  fixtures regenerated with wolfSSL's own encoder so the codec is
  pinned to RFC 9909.
- New unit test test_wc_slhdsa_x509_i2d_roundtrip exercises the raw
  PublicKeyDecode entry point that wolfssl_x509_make_der relies on.
- test_wc_slhdsa_check_key now tests both Public-then-Private and
  Private-then-Public import orderings.

Build / ABI:
- DYNAMIC_TYPE_SPHINCS = 98 kept as RESERVED with a tombstone comment
  for ABI stability; new code should use DYNAMIC_TYPE_SLHDSA (107).
- All build system / IDE project files updated; SPHINCS+ sources,
  headers, and test data removed.
- Dead bench_slhdsa_*_key arrays removed from gencertbuf.pl and
  certs_test.h; the .der files on disk drive the decode tests.

Author: Frauschi

.wolfssl_known_macro_extras

@@ -851,7 +851,6 @@ WOLFSSL_NO_SERVER_GROUPS_EXT
 WOLFSSL_NO_SESSION_STATS
 WOLFSSL_NO_SIGALG
 WOLFSSL_NO_SOCKADDR_UN
-WOLFSSL_NO_SPHINCS
 WOLFSSL_NO_STRICT_CIPHER_SUITE
 WOLFSSL_NO_TICKET_EXPIRE
 WOLFSSL_NO_TRUSTED_CERTS_VERIFY

IDE/Espressif/ESP-IDF/examples/template/components/wolfssl/component.mk

@@ -245,7 +245,6 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/siphash.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm2.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm3.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm4.o
-COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sphincs.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm32.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm64.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_armthumb.o
@@ -271,6 +270,7 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_mlkem_poly.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_lms.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_pkcs11.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_port.o
+COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_slhdsa.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_xmss.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_first.o # autogen exclusion
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_last.o  # autogen exclusion

IDE/Espressif/ESP-IDF/examples/wolfssl_benchmark/components/wolfssl/component.mk

@@ -245,7 +245,6 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/siphash.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm2.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm3.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm4.o
-COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sphincs.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm32.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm64.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_armthumb.o
@@ -271,6 +270,7 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_mlkem_poly.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_lms.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_pkcs11.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_port.o
+COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_slhdsa.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_xmss.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_first.o # autogen exclusion
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_last.o  # autogen exclusion

IDE/Espressif/ESP-IDF/examples/wolfssl_client/components/wolfssl/component.mk

@@ -245,7 +245,6 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/siphash.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm2.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm3.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm4.o
-COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sphincs.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm32.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm64.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_armthumb.o
@@ -271,6 +270,7 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_mlkem_poly.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_lms.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_pkcs11.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_port.o
+COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_slhdsa.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_xmss.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_first.o # autogen exclusion
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_last.o  # autogen exclusion

IDE/Espressif/ESP-IDF/examples/wolfssl_server/components/wolfssl/component.mk

@@ -245,7 +245,6 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/siphash.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm2.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm3.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm4.o
-COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sphincs.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm32.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm64.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_armthumb.o
@@ -271,6 +270,7 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_mlkem_poly.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_lms.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_pkcs11.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_port.o
+COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_slhdsa.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_xmss.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_first.o # autogen exclusion
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_last.o  # autogen exclusion

IDE/Espressif/ESP-IDF/examples/wolfssl_test/components/wolfssl/component.mk

@@ -245,7 +245,6 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/siphash.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm2.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm3.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sm4.o
-COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sphincs.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm32.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_arm64.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/sp_armthumb.o
@@ -271,6 +270,7 @@ COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_mlkem_poly.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_lms.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_pkcs11.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_port.o
+COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_slhdsa.o
 COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wc_xmss.o
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_first.o # autogen exclusion
 # COMPONENT_OBJS += $(WOLFSSL_ROOT)/wolfcrypt/src/wolfcrypt_last.o  # autogen exclusion

IDE/INTIME-RTOS/Makefile

@@ -320,7 +320,6 @@ INCL_TARGS := 	wolfssl/callbacks.h \
 	wolfssl/wolfcrypt/sm4.h \
 	wolfssl/wolfcrypt/sp.h \
 	wolfssl/wolfcrypt/sp_int.h \
-	wolfssl/wolfcrypt/sphincs.h \
 	wolfssl/wolfcrypt/srp.h \
 	wolfssl/wolfcrypt/tfm.h \
 	wolfssl/wolfcrypt/types.h \
@@ -329,6 +328,7 @@ INCL_TARGS := 	wolfssl/callbacks.h \
 	wolfssl/wolfcrypt/wc_kyber.h \
 	wolfssl/wolfcrypt/wc_pkcs11.h \
 	wolfssl/wolfcrypt/wc_port.h \
+	wolfssl/wolfcrypt/wc_slhdsa.h \
 	wolfssl/wolfcrypt/wolfevent.h \
 	wolfssl/wolfcrypt/wolfmath.h \
 	wolfssl/wolfcrypt/xmss.h \

IDE/INTIME-RTOS/libwolfssl.vcxproj

@@ -81,7 +81,6 @@
 	<ClCompile Include="..\..\wolfcrypt\src\sha3.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sha512.c" />
     <ClCompile Include="..\..\wolfcrypt\src\signature.c" />
-	<ClCompile Include="..\..\wolfcrypt\src\sphincs.c" />
 	<ClCompile Include="..\..\wolfcrypt\src\sp_c32.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sp_c64.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sp_int.c" />
@@ -93,6 +92,7 @@
     <ClCompile Include="..\..\wolfcrypt\src\wolfevent.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wolfmath.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wc_pkcs11.c" />
+    <ClCompile Include="..\..\wolfcrypt\src\wc_slhdsa.c" />
     <ClCompile Include="..\..\wolfcrypt\src\port\liboqs\liboqs.c" />
 
   </ItemGroup>
@@ -164,6 +164,7 @@
     <ClInclude Include="..\..\wolfssl\wolfcrypt\visibility.h" />
     <ClInclude Include="..\..\wolfssl\wolfcrypt\wc_encrypt.h" />
     <ClInclude Include="..\..\wolfssl\wolfcrypt\wc_port.h" />
+    <ClInclude Include="..\..\wolfssl\wolfcrypt\wc_slhdsa.h" />
     <ClInclude Include="..\..\wolfssl\wolfcrypt\wolfevent.h" />
     <ClInclude Include="..\..\wolfssl\wolfcrypt\wolfmath.h" />
   </ItemGroup>

IDE/INTIME-RTOS/wolfssl-lib.vcxproj

@@ -108,7 +108,6 @@
     <ClCompile Include="..\..\wolfcrypt\src\sm2.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sm3.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sm4.c" />
-    <ClCompile Include="..\..\wolfcrypt\src\sphincs.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sp_arm32.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sp_arm64.c" />
     <ClCompile Include="..\..\wolfcrypt\src\sp_armthumb.c" />
@@ -190,6 +189,7 @@
     <ClCompile Include="..\..\wolfcrypt\src\tfm.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wc_encrypt.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wc_port.c" />
+    <ClCompile Include="..\..\wolfcrypt\src\wc_slhdsa.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wolfevent.c" />
     <ClCompile Include="..\..\wolfcrypt\src\wolfmath.c" />
   </ItemGroup>

IDE/MPLABX16/wolfssl.X/nbproject/configurations.xml

@@ -81,12 +81,12 @@
         <itemPath>../../../wolfcrypt/src/sp_c32.c</itemPath>
         <itemPath>../../../wolfcrypt/src/sp_c64.c</itemPath>
         <itemPath>../../../wolfcrypt/src/sp_int.c</itemPath>
-        <itemPath>../../../wolfcrypt/src/sphincs.c</itemPath>
         <itemPath>../../../wolfcrypt/src/srp.c</itemPath>
         <itemPath>../../../wolfcrypt/src/tfm.c</itemPath>
         <itemPath>../../../wolfcrypt/src/wc_encrypt.c</itemPath>
         <itemPath>../../../wolfcrypt/src/wc_pkcs11.c</itemPath>
         <itemPath>../../../wolfcrypt/src/wc_port.c</itemPath>
+        <itemPath>../../../wolfcrypt/src/wc_slhdsa.c</itemPath>
         <itemPath>../../../wolfcrypt/src/wolfevent.c</itemPath>
         <itemPath>../../../wolfcrypt/src/wolfmath.c</itemPath>
       </logicalFolder>