Add RAKP MD5/SHA256 format support

doc/NEWS

@@ -488,6 +488,11 @@ Major changes from 1.9.0-jumbo-1 (May 2019) in this bleeding-edge version:
 - Add support to keepass2john for the current format of KeePass XML keyfiles.
   The formats needed no changes.  [magnum; 2025]
 
+- Added RAKP-MD5 and RAKP-SHA256 CPU and OpenCL formats for IPMI 2.0 RAKP
+  (RMCP+) challenge-response hashes in the existing "$rakp$<salt>$<hmac>"
+  syntax, where digest length selects MD5 (32), SHA1 (40), or SHA256 (64).
+  [HD Moore; 2026]
+
 
 Major changes from 1.8.0-jumbo-1 (December 2014) to 1.9.0-jumbo-1 (May 2019):
 

run/opencl/rakp_md5_kernel.cl

@@ -0,0 +1,39 @@
+/*
+ * OpenCL kernel for IPMI 2.0 RAKP (RMCP+) HMAC-MD5 (RAKP auth algorithm 2).
+ *
+ * Copyright (c) 2026 HD Moore, released to the general public under the
+ * following terms:
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted.
+ *
+ * One work-item per candidate. Keys are packed (key_array + index[gid]); the
+ * RAKP salt (raw bytes + length) is the HMAC message. Uses the shared
+ * opencl_hmac_md5 helper so the HMAC construction stays correct and simple.
+ */
+
+#include "opencl_misc.h"
+#define HMAC_KEY_TYPE __global const
+#include "opencl_hmac_md5.h"
+
+__kernel void rakp_md5_kernel(__global const uchar *salt,
+                              const uint salt_len,
+                              __global const uint *key_array,
+                              __global const uint *index,
+                              __global uint *digest)
+{
+	uint gid = get_global_id(0);
+	uint base = index[gid];
+	uint key_len = base & 63;
+	__global const uchar *key = (__global const uchar *)(key_array + (base >> 6));
+	uchar saltbuf[128];
+	uint out[4];
+	uint i;
+
+	for (i = 0; i < salt_len; i++)
+		saltbuf[i] = salt[i];
+
+	hmac_md5(key, key_len, saltbuf, salt_len, out, 16);
+
+	for (i = 0; i < 4; i++)
+		digest[gid * 4 + i] = out[i];
+}

run/opencl/rakp_sha256_kernel.cl

@@ -0,0 +1,39 @@
+/*
+ * OpenCL kernel for IPMI 2.0 RAKP (RMCP+) HMAC-SHA256 (RAKP auth algorithm 3).
+ *
+ * Copyright (c) 2026 HD Moore, released to the general public under the
+ * following terms:
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted.
+ *
+ * One work-item per candidate. Keys are packed (key_array + index[gid]); the
+ * RAKP salt (raw bytes + length) is the HMAC message. Uses the shared
+ * opencl_hmac_sha256 helper so the HMAC construction stays correct and simple.
+ */
+
+#include "opencl_misc.h"
+#define HMAC_KEY_TYPE __global const
+#include "opencl_hmac_sha256.h"
+
+__kernel void rakp_sha256_kernel(__global const uchar *salt,
+                                 const uint salt_len,
+                                 __global const uint *key_array,
+                                 __global const uint *index,
+                                 __global uint *digest)
+{
+	uint gid = get_global_id(0);
+	uint base = index[gid];
+	uint key_len = base & 63;
+	__global const uchar *key = (__global const uchar *)(key_array + (base >> 6));
+	uchar saltbuf[128];
+	uint out[8];
+	uint i;
+
+	for (i = 0; i < salt_len; i++)
+		saltbuf[i] = salt[i];
+
+	hmac_sha256(key, key_len, saltbuf, salt_len, out, 32);
+
+	for (i = 0; i < 8; i++)
+		digest[gid * 8 + i] = out[i];
+}