Add XMSS-SHAKE256_{10, 16, 20}_256 parameters (#1819)

* add XMSS-SHAKE256_*_256 parameters Signed-off-by: Duc Tri Nguyen <[email protected]> * [trigger downstream] Signed-off-by: Duc Tri Nguyen <[email protected]> --------- Signed-off-by: Duc Tri Nguyen <[email protected]>
open-quantum-safe · Jun 25, 2024 · 51ddd33 · 51ddd33
1 parent e3f05cb
commit 51ddd33
Show file tree

Hide file tree

Showing 17 changed files with 231 additions and 2 deletions.
diff --git a/.CMake/alg_support.cmake b/.CMake/alg_support.cmake
@@ -516,6 +516,9 @@ cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_sha256_h20_192 "" ON "OQS_ENABLE
 cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h10_192 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
 cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h16_192 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
 cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h20_192 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
+cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
+cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
+cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
 
 cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)
 cmake_dependent_option(OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_4 "" ON "OQS_ENABLE_SIG_STFL_XMSS" OFF)

diff --git a/README.md b/README.md
@@ -69,7 +69,7 @@ All names other than `ML-KEM` and `ML-DSA` are subject to change. `liboqs` makes
 - **SPHINCS+-SHA2**: SPHINCS+-SHA2-128f-simple, SPHINCS+-SHA2-128s-simple, SPHINCS+-SHA2-192f-simple, SPHINCS+-SHA2-192s-simple, SPHINCS+-SHA2-256f-simple, SPHINCS+-SHA2-256s-simple
 - **SPHINCS+-SHAKE**: SPHINCS+-SHAKE-128f-simple, SPHINCS+-SHAKE-128s-simple, SPHINCS+-SHAKE-192f-simple, SPHINCS+-SHAKE-192s-simple, SPHINCS+-SHAKE-256f-simple, SPHINCS+-SHAKE-256s-simple
 <!--- OQS_TEMPLATE_FRAGMENT_LIST_SIGS_END -->
-- **XMSS**: XMSS-SHA2_10_256, XMSS-SHA2_16_256, XMSS-SHA2_20_256, XMSS-SHAKE_10_256, XMSS-SHAKE_16_256, XMSS-SHAKE_20_256, XMSS-SHA2_10_512, XMSS-SHA2_16_512, XMSS-SHA2_20_512, XMSS-SHAKE_10_512, XMSS-SHAKE_16_512, XMSS-SHAKE_20_512, XMSS-SHA2_10_192, XMSS-SHA2_16_192, XMSS-SHA2_20_192, XMSS-SHAKE256_10_192, XMSS-SHAKE256_16_192, XMSS-SHAKE256_20_192, XMSSMT-SHA2_20/2_256, XMSSMT-SHA2_20/4_256, XMSSMT-SHA2_40/2_256, XMSSMT-SHA2_40/4_256, XMSSMT-SHA2_40/8_256, XMSSMT-SHA2_60/3_256, XMSSMT-SHA2_60/6_256, XMSSMT-SHA2_60/12_256, XMSSMT-SHAKE_20/2_256, XMSSMT-SHAKE_20/4_256, XMSSMT-SHAKE_40/2_256, XMSSMT-SHAKE_40/4_256, XMSSMT-SHAKE_40/8_256, XMSSMT-SHAKE_60/3_256, XMSSMT-SHAKE_60/6_256, XMSSMT-SHAKE_60/12_256 
+- **XMSS**: XMSS-SHA2_10_256, XMSS-SHA2_16_256, XMSS-SHA2_20_256, XMSS-SHAKE_10_256, XMSS-SHAKE_16_256, XMSS-SHAKE_20_256, XMSS-SHA2_10_512, XMSS-SHA2_16_512, XMSS-SHA2_20_512, XMSS-SHAKE_10_512, XMSS-SHAKE_16_512, XMSS-SHAKE_20_512, XMSS-SHA2_10_192, XMSS-SHA2_16_192, XMSS-SHA2_20_192, XMSS-SHAKE256_10_192, XMSS-SHAKE256_16_192, XMSS-SHAKE256_20_192, SHAKE256_10_256, SHAKE256_16_256, SHAKE256_20_256, XMSSMT-SHA2_20/2_256, XMSSMT-SHA2_20/4_256, XMSSMT-SHA2_40/2_256, XMSSMT-SHA2_40/4_256, XMSSMT-SHA2_40/8_256, XMSSMT-SHA2_60/3_256, XMSSMT-SHA2_60/6_256, XMSSMT-SHA2_60/12_256, XMSSMT-SHAKE_20/2_256, XMSSMT-SHAKE_20/4_256, XMSSMT-SHAKE_40/2_256, XMSSMT-SHAKE_40/4_256, XMSSMT-SHAKE_40/8_256, XMSSMT-SHAKE_60/3_256, XMSSMT-SHAKE_60/6_256, XMSSMT-SHAKE_60/12_256 
 - **LMS**: LMS_SHA256_H5_W1, LMS_SHA256_H5_W2, LMS_SHA256_H5_W4, LMS_SHA256_H5_W8, LMS_SHA256_H10_W1, LMS_SHA256_H10_W2, LMS_SHA256_H10_W4, LMS_SHA256_H10_W8, LMS_SHA256_H15_W1, LMS_SHA256_H15_W2, LMS_SHA256_H15_W4, LMS_SHA256_H15_W8, LMS_SHA256_H20_W1, LMS_SHA256_H20_W2, LMS_SHA256_H20_W4, LMS_SHA256_H20_W8, LMS_SHA256_H25_W1, LMS_SHA256_H25_W2, LMS_SHA256_H25_W4, LMS_SHA256_H25_W8, LMS_SHA256_H5_W8_H5_W8, LMS_SHA256_H10_W4_H5_W8, LMS_SHA256_H10_W8_H5_W8, LMS_SHA256_H10_W2_H10_W2, LMS_SHA256_H10_W4_H10_W4, LMS_SHA256_H10_W8_H10_W8, LMS_SHA256_H15_W8_H5_W8, LMS_SHA256_H15_W8_H10_W8, LMS_SHA256_H15_W8_H15_W8, LMS_SHA256_H20_W8_H5_W8, LMS_SHA256_H20_W8_H10_W8, LMS_SHA256_H20_W8_H15_W8, LMS_SHA256_H20_W8_H20_W8
 
 Note that for algorithms marked with a dagger (†), liboqs contains at least one implementation that uses a large amount of stack space; this may cause failures when run in threads or in constrained environments. For more information, consult the algorithm information sheets in the [docs/algorithms](https://github.com/open-quantum-safe/liboqs/tree/main/docs/algorithms) folder.

diff --git a/docs/algorithms/sig_stfl/xmss.md b/docs/algorithms/sig_stfl/xmss.md
@@ -32,6 +32,9 @@
 |  XMSS-SHAKE256_10_192  |                  |                      |                        48 |                      1053 |                     1492 |
 |  XMSS-SHAKE256_16_192  |                  |                      |                        48 |                      1605 |                     1636 |
 |  XMSS-SHAKE256_20_192  |                  |                      |                        48 |                      1973 |                     1732 |
+|  XMSS-SHAKE256_10_256  |                  |                      |                        64 |                      1373 |                     2500 |
+|  XMSS-SHAKE256_16_256  |                  |                      |                        64 |                      2093 |                     2692 |
+|  XMSS-SHAKE256_20_256  |                  |                      |                        64 |                      2573 |                     2820 |
 |  XMSSMT-SHA2_20/2_256  |                  |                      |                        64 |                      5998 |                     4963 |
 |  XMSSMT-SHA2_20/4_256  |                  |                      |                        64 |                     10938 |                     9251 |
 |  XMSSMT-SHA2_40/2_256  |                  |                      |                        64 |                      9600 |                     5605 |

diff --git a/docs/algorithms/sig_stfl/xmss.yml b/docs/algorithms/sig_stfl/xmss.yml
@@ -125,6 +125,24 @@ parameter-sets:
   length-public-key: 48
   length-secret-key: 1973
   length-signature: 1732
+- name: XMSS-SHAKE256_10_256
+  claimed-nist-level:
+  claimed-security:
+  length-public-key: 64
+  length-secret-key: 1373
+  length-signature: 2500
+- name: XMSS-SHAKE256_16_256
+  claimed-nist-level:
+  claimed-security:
+  length-public-key: 64
+  length-secret-key: 2093
+  length-signature: 2692
+- name: XMSS-SHAKE256_20_256
+  claimed-nist-level:
+  claimed-security:
+  length-public-key: 64
+  length-secret-key: 2573
+  length-signature: 2820
 - name: XMSSMT-SHA2_20/2_256
   claimed-nist-level:
   claimed-security:

diff --git a/src/oqsconfig.h.cmake b/src/oqsconfig.h.cmake
@@ -210,6 +210,9 @@
 #cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h10_192 1
 #cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h16_192 1
 #cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h20_192 1
+#cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256 1
+#cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256 1
+#cmakedefine OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256 1
 
 #cmakedefine OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2 1
 #cmakedefine OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_4 1

diff --git a/src/sig_stfl/sig_stfl.c b/src/sig_stfl/sig_stfl.c
@@ -41,6 +41,9 @@ OQS_API const char *OQS_SIG_STFL_alg_identifier(size_t i) {
 		OQS_SIG_STFL_alg_xmss_shake256_h10_192,
 		OQS_SIG_STFL_alg_xmss_shake256_h16_192,
 		OQS_SIG_STFL_alg_xmss_shake256_h20_192,
+		OQS_SIG_STFL_alg_xmss_shake256_h10_256,
+		OQS_SIG_STFL_alg_xmss_shake256_h16_256,
+		OQS_SIG_STFL_alg_xmss_shake256_h20_256,
 		OQS_SIG_STFL_alg_xmssmt_sha256_h20_2,
 		OQS_SIG_STFL_alg_xmssmt_sha256_h20_4,
 		OQS_SIG_STFL_alg_xmssmt_sha256_h40_2,
@@ -225,6 +228,24 @@ OQS_API int OQS_SIG_STFL_alg_is_enabled(const char *method_name) {
 		return 1;
 #else
 		return 0;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h10_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256
+		return 1;
+#else
+		return 0;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h16_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256
+		return 1;
+#else
+		return 0;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h20_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256
+		return 1;
+#else
+		return 0;
 #endif
 	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmssmt_sha256_h20_2)) {
 #ifdef OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2
@@ -649,6 +670,24 @@ OQS_API OQS_SIG_STFL *OQS_SIG_STFL_new(const char *method_name) {
 		return OQS_SIG_STFL_alg_xmss_shake256_h20_192_new();
 #else
 		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h10_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256
+		return OQS_SIG_STFL_alg_xmss_shake256_h10_256_new();
+#else
+		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h16_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256
+		return OQS_SIG_STFL_alg_xmss_shake256_h16_256_new();
+#else
+		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h20_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256
+		return OQS_SIG_STFL_alg_xmss_shake256_h20_256_new();
+#else
+		return NULL;
 #endif
 	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmssmt_sha256_h20_2)) {
 #ifdef OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2
@@ -1146,6 +1185,24 @@ OQS_API OQS_SIG_STFL_SECRET_KEY *OQS_SIG_STFL_SECRET_KEY_new(const char *method_
 		return OQS_SECRET_KEY_XMSS_SHAKE256_H20_192_new();
 #else
 		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h10_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256
+		return OQS_SECRET_KEY_XMSS_SHAKE256_H10_256_new();
+#else
+		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h16_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256
+		return OQS_SECRET_KEY_XMSS_SHAKE256_H16_256_new();
+#else
+		return NULL;
+#endif
+	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmss_shake256_h20_256)) {
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256
+		return OQS_SECRET_KEY_XMSS_SHAKE256_H20_256_new();
+#else
+		return NULL;
 #endif
 	} else if (0 == strcasecmp(method_name, OQS_SIG_STFL_alg_xmssmt_sha256_h20_2)) {
 #ifdef OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2

diff --git a/src/sig_stfl/sig_stfl.h b/src/sig_stfl/sig_stfl.h
@@ -62,6 +62,9 @@ extern "C"
 #define OQS_SIG_STFL_alg_xmss_shake256_h10_192 "XMSS-SHAKE256_10_192"
 #define OQS_SIG_STFL_alg_xmss_shake256_h16_192 "XMSS-SHAKE256_16_192"
 #define OQS_SIG_STFL_alg_xmss_shake256_h20_192 "XMSS-SHAKE256_20_192"
+#define OQS_SIG_STFL_alg_xmss_shake256_h10_256 "XMSS-SHAKE256_10_256"
+#define OQS_SIG_STFL_alg_xmss_shake256_h16_256 "XMSS-SHAKE256_16_256"
+#define OQS_SIG_STFL_alg_xmss_shake256_h20_256 "XMSS-SHAKE256_20_256"
 
 #define OQS_SIG_STFL_alg_xmssmt_sha256_h20_2 "XMSSMT-SHA2_20/2_256"
 #define OQS_SIG_STFL_alg_xmssmt_sha256_h20_4 "XMSSMT-SHA2_20/4_256"
@@ -129,7 +132,7 @@ extern "C"
 /*
  * Total number of stateful variants defined above, used to create the tracking array
  */
-#define OQS_SIG_STFL_algs_length 67
+#define OQS_SIG_STFL_algs_length 70
 
 typedef struct OQS_SIG_STFL_SECRET_KEY OQS_SIG_STFL_SECRET_KEY;
 

diff --git a/src/sig_stfl/xmss/CMakeLists.txt b/src/sig_stfl/xmss/CMakeLists.txt
@@ -124,6 +124,24 @@ if (OQS_ENABLE_SIG_STFL_xmss_shake256_h20_192)
     set(_XMSS_OBJS ${_XMSS_OBJS} $<TARGET_OBJECTS:xmss_shake256_h20_192>)
 endif()
 
+if (OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256)
+    add_library(xmss_shake256_h10_256 OBJECT sig_stfl_xmss_shake256_h10_256.c sig_stfl_xmss_functions.c ${SRCS})
+    target_compile_options(xmss_shake256_h10_256 PRIVATE -DXMSS_PARAMS_NAMESPACE=xmss_shake256_h10_256 -DHASH=5)
+    set(_XMSS_OBJS ${_XMSS_OBJS} $<TARGET_OBJECTS:xmss_shake256_h10_256>)
+endif()
+
+if (OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256)
+    add_library(xmss_shake256_h16_256 OBJECT sig_stfl_xmss_shake256_h16_256.c sig_stfl_xmss_functions.c ${SRCS})
+    target_compile_options(xmss_shake256_h16_256 PRIVATE -DXMSS_PARAMS_NAMESPACE=xmss_shake256_h16_256 -DHASH=5)
+    set(_XMSS_OBJS ${_XMSS_OBJS} $<TARGET_OBJECTS:xmss_shake256_h16_256>)
+endif()
+
+if (OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256)
+    add_library(xmss_shake256_h20_256 OBJECT sig_stfl_xmss_shake256_h20_256.c sig_stfl_xmss_functions.c ${SRCS})
+    target_compile_options(xmss_shake256_h20_256 PRIVATE -DXMSS_PARAMS_NAMESPACE=xmss_shake256_h20_256 -DHASH=5)
+    set(_XMSS_OBJS ${_XMSS_OBJS} $<TARGET_OBJECTS:xmss_shake256_h20_256>)
+endif()
+
 if (OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2)
     add_library(xmssmt_sha256_h20_2 OBJECT sig_stfl_xmssmt_sha256_h20_2.c sig_stfl_xmssmt_functions.c ${SRCS})
     target_compile_options(xmssmt_sha256_h20_2 PRIVATE -DXMSS_PARAMS_NAMESPACE=xmssmt_sha256_h20_2 -DHASH=3)

diff --git a/src/sig_stfl/xmss/sig_stfl_xmss.h b/src/sig_stfl/xmss/sig_stfl_xmss.h
@@ -35,6 +35,10 @@
  * | XMSS-SHA2_16_192              | 0x0e |  1605  |   48   |  1636   | 24 |    ❌   |       ✅        |    ✅    |
  * | XMSS-SHA2_20_192              | 0x0f |  1973  |   48   |  1732   | 24 |    ❌   |       ✅        |    ✅    |
  *
+ * | XMSS-SHAKE256_10_256          | 0x10 |  1373  |   64   |  2500   | 32 |    ❌   |       ✅        |    ✅    |
+ * | XMSS-SHAKE256_16_256          | 0x11 |  2093  |   64   |  2692   | 32 |    ❌   |       ✅        |    ✅    |
+ * | XMSS-SHAKE256_20_256          | 0x12 |  2573  |   64   |  2820   | 32 |    ❌   |       ✅        |    ✅    |
+ *
  * | XMSS-SHAKE256_10_192          | 0x13 |  1053  |   48   |  1492   | 24 |    ❌   |       ✅        |    ✅    |
  * | XMSS-SHAKE256_16_192          | 0x14 |  1605  |   48   |  1636   | 24 |    ❌   |       ✅        |    ✅    |
  * | XMSS-SHAKE256_20_192          | 0x15 |  1973  |   48   |  1732   | 24 |    ❌   |       ✅        |    ✅    |
@@ -364,6 +368,57 @@ OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_192_sigs_total(unsigned lo
 
 #endif
 
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h10_256
+
+#define OQS_SIG_STFL_alg_xmss_shake256_h10_256_oid 0x10
+#define OQS_SIG_STFL_alg_xmss_shake256_h10_256_length_sk (1373 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h10_256_length_pk (64 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h10_256_length_signature 2500
+
+OQS_API OQS_SIG_STFL *OQS_SIG_STFL_alg_xmss_shake256_h10_256_new(void);
+OQS_API OQS_SIG_STFL_SECRET_KEY *OQS_SECRET_KEY_XMSS_SHAKE256_H10_256_new(void);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h10_256_keypair(uint8_t *public_key, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h10_256_sign(uint8_t *signature, size_t *signature_len, const uint8_t *message, size_t message_len, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h10_256_verify(const uint8_t *message, size_t message_len, const uint8_t *signature, size_t signature_len, const uint8_t *public_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h10_256_sigs_remaining(unsigned long long *remain, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h10_256_sigs_total(unsigned long long *total, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+
+#endif
+
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h16_256
+
+#define OQS_SIG_STFL_alg_xmss_shake256_h16_256_oid 0x11
+#define OQS_SIG_STFL_alg_xmss_shake256_h16_256_length_sk (2093 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h16_256_length_pk (64 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h16_256_length_signature 2692
+
+OQS_API OQS_SIG_STFL *OQS_SIG_STFL_alg_xmss_shake256_h16_256_new(void);
+OQS_API OQS_SIG_STFL_SECRET_KEY *OQS_SECRET_KEY_XMSS_SHAKE256_H16_256_new(void);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h16_256_keypair(uint8_t *public_key, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h16_256_sign(uint8_t *signature, size_t *signature_len, const uint8_t *message, size_t message_len, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h16_256_verify(const uint8_t *message, size_t message_len, const uint8_t *signature, size_t signature_len, const uint8_t *public_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h16_256_sigs_remaining(unsigned long long *remain, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h16_256_sigs_total(unsigned long long *total, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+
+#endif
+
+#ifdef OQS_ENABLE_SIG_STFL_xmss_shake256_h20_256
+
+#define OQS_SIG_STFL_alg_xmss_shake256_h20_256_oid 0x12
+#define OQS_SIG_STFL_alg_xmss_shake256_h20_256_length_sk (2573 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h20_256_length_pk (64 + XMSS_OID_LEN)
+#define OQS_SIG_STFL_alg_xmss_shake256_h20_256_length_signature 2820
+
+OQS_API OQS_SIG_STFL *OQS_SIG_STFL_alg_xmss_shake256_h20_256_new(void);
+OQS_API OQS_SIG_STFL_SECRET_KEY *OQS_SECRET_KEY_XMSS_SHAKE256_H20_256_new(void);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_256_keypair(uint8_t *public_key, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_256_sign(uint8_t *signature, size_t *signature_len, const uint8_t *message, size_t message_len, OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_256_verify(const uint8_t *message, size_t message_len, const uint8_t *signature, size_t signature_len, const uint8_t *public_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_256_sigs_remaining(unsigned long long *remain, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+OQS_API OQS_STATUS OQS_SIG_STFL_alg_xmss_shake256_h20_256_sigs_total(unsigned long long *total, const OQS_SIG_STFL_SECRET_KEY *secret_key);
+
+#endif
+
 #ifdef OQS_ENABLE_SIG_STFL_xmssmt_sha256_h20_2
 
 #define OQS_SIG_STFL_alg_xmssmt_sha256_h20_2_oid 0x01

diff --git a/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h10_256.c b/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h10_256.c
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: (Apache-2.0 OR MIT) AND CC0-1.0
+
+#include "sig_stfl_xmss_xmssmt.c"
+
+// ======================== XMSS-SHAKE256_10_256 ======================== //
+
+XMSS_ALG(, _shake256_h10_256, _SHAKE256_H10_256)
diff --git a/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h16_256.c b/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h16_256.c
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: (Apache-2.0 OR MIT) AND CC0-1.0
+
+#include "sig_stfl_xmss_xmssmt.c"
+
+// ======================== XMSS-SHAKE256_16_256 ======================== //
+
+XMSS_ALG(, _shake256_h16_256, _SHAKE256_H16_256)
diff --git a/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h20_256.c b/src/sig_stfl/xmss/sig_stfl_xmss_shake256_h20_256.c
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: (Apache-2.0 OR MIT) AND CC0-1.0
+
+#include "sig_stfl_xmss_xmssmt.c"
+
+// ======================== XMSS-SHAKE256_20_256 ======================== //
+
+XMSS_ALG(, _shake256_h20_256, _SHAKE256_H20_256)
diff --git a/tests/KATs/sig_stfl/kats.json b/tests/KATs/sig_stfl/kats.json
@@ -17,6 +17,9 @@
     "XMSS-SHAKE256_10_192": "b62a1dbc2f8920df2f5a164ed175829ed95d5b3301269b0ab2452cd46b4261d6",
     "XMSS-SHAKE256_16_192": "935570c4bc7c61e4cdc0517182766dcee53ceec71f91b8dd969568a7f8b76db1",
     "XMSS-SHAKE256_20_192": "18067167a1eeee294bf1f0e3087e468b512f7c0c4cfad9c449dc425aab45336b",
+    "XMSS-SHAKE256_10_256": "7cbb582c6723cb86a9c775151865a67f3f9fa30140beab8f115cd4a7dc15eb2d",
+    "XMSS-SHAKE256_16_256": "ccc819bc17f78cdb4f2733b97350b7ef351e07d1456564a4185247db1a682fe3",
+    "XMSS-SHAKE256_20_256": "01ace5400a407030b0cb43ed0982c5f378a1d0c4108fdca2b70bc4ba78067c7f",
     "XMSSMT-SHA2_20/2_256": "9f117294999c886ac6b69d6f32c3fc152599343add210f4464aee5d1ca0ec34d",
     "XMSSMT-SHA2_20/4_256": "0c990e8ff8189140e8539b11ae3f85040544fc7d549f8db17d83392569647de9",
     "XMSSMT-SHA2_40/2_256": "91605c4b67afb4e17d57ed076e10d3c4287264deea4a46092e374199c041d489",