HMAC-BLAKE2s, HKDF, TAI64N 実装追加

暗号プリミティブ実装: - HMAC-BLAKE2s (RFC 2104): BLAKE2s ベースの HMAC - HKDF-BLAKE2s (RFC 586): 鍵導出関数 - HKDF-Extract: 入力鍵から PRK を導出 - HKDF-Expand: PRK から必要な長さの鍵を導出 - TAI64N: WireGuard プロトコル層のタイムスタンプ（12 バイト） WireGuard での使用: - ハンドシェイク中の鍵導出チェーン - チェーン鍵 (Ck)・セッション鍵 (tk) の導出 - リプレイ防止用タイムスタンプテスト: - test_hmac_blake2s: HMAC-BLAKE2s 検証 ✅ - test_hkdf_blake2s: HKDF 検証 ✅ - test_tai64n: TAI64N エンコード/デコード ✅
2026-03-26 21:03:27 +09:00
parent b83394f37b
commit c892e6ca01
11 changed files with 695 additions and 3 deletions
@@ -0,0 +1,63 @@
+/**
+ * @file se050_hkdf_blake2s.h
+ * @brief HKDF Implementation using HMAC-BLAKE2s (RFC 586)
+ */
+
+#ifndef SE050_HKDF_BLAKE2S_H
+#define SE050_HKDF_BLAKE2S_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief HKDF-Extract (RFC 586 Section 2.2)
+ * @param prk Output pseudorandom key (32 bytes)
+ * @param salt Salt value (can be NULL for zero salt)
+ * @param saltlen Salt length
+ * @param ikm Input keying material
+ * @param ikmlen Input keying material length
+ * @return 0 on success, -1 on error
+ */
+int se050_hkdf_extract(uint8_t prk[32],
+                       const uint8_t *salt, size_t saltlen,
+                       const uint8_t *ikm, size_t ikmlen);
+
+/**
+ * @brief HKDF-Expand (RFC 586 Section 2.3)
+ * @param okm Output keying material
+ * @param okmlen Output keying material length (max 255 * 32 bytes)
+ * @param prk Pseudorandom key from Extract
+ * @param info Application-specific context
+ * @param infolen Info length
+ * @return 0 on success, -1 on error
+ */
+int se050_hkdf_expand(uint8_t *okm, size_t okmlen,
+                      const uint8_t prk[32],
+                      const uint8_t *info, size_t infolen);
+
+/**
+ * @brief HKDF (combined Extract + Expand)
+ * @param okm Output keying material
+ * @param okmlen Output keying material length
+ * @param salt Salt value (can be NULL)
+ * @param saltlen Salt length
+ * @param ikm Input keying material
+ * @param ikmlen Input keying material length
+ * @param info Application-specific context
+ * @param infolen Info length
+ * @return 0 on success, -1 on error
+ */
+int se050_hkdf(uint8_t *okm, size_t okmlen,
+               const uint8_t *salt, size_t saltlen,
+               const uint8_t *ikm, size_t ikmlen,
+               const uint8_t *info, size_t infolen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SE050_HKDF_BLAKE2S_H */
@@ -0,0 +1,50 @@
+/**
+ * @file se050_hmac_blake2s.h
+ * @brief HMAC-BLAKE2s Implementation (RFC 2104)
+ */
+
+#ifndef SE050_HMAC_BLAKE2S_H
+#define SE050_HMAC_BLAKE2S_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define HMAC_BLAKE2S_BLOCK_SIZE 64
+#define HMAC_BLAKE2S_DIGEST_SIZE 32
+
+/**
+ * @brief Compute HMAC-BLAKE2s
+ * @param out Output buffer (32 bytes)
+ * @param key Key data
+ * @param keylen Key length (1-64 bytes)
+ * @param data Input data
+ * @param datalen Input data length
+ * @return 0 on success, -1 on error
+ */
+int se050_hmac_blake2s(uint8_t out[32],
+                       const uint8_t *key, size_t keylen,
+                       const uint8_t *data, size_t datalen);
+
+/**
+ * @brief One-shot HMAC-BLAKE2s with variable output length
+ * @param out Output buffer
+ * @param outlen Output length (1-32 bytes)
+ * @param key Key data
+ * @param keylen Key length
+ * @param data Input data
+ * @param datalen Input data length
+ * @return 0 on success, -1 on error
+ */
+int se050_hmac_blake2s_variable(uint8_t *out, size_t outlen,
+                                const uint8_t *key, size_t keylen,
+                                const uint8_t *data, size_t datalen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SE050_HMAC_BLAKE2S_H */
@@ -0,0 +1,68 @@
+/**
+ * @file se050_tai64n.h
+ * @brief TAI64N Timestamp Encoding (WireGuard Protocol Layer)
+ * RFC 7539 Section 7.2.1
+ */
+
+#ifndef SE050_TAI64N_H
+#define SE050_TAI64N_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define TAI64N_SIZE 12
+#define TAI64_BASE 0x4000000000000010ULL
+
+/**
+ * @brief TAI64N timestamp structure (12 bytes)
+ */
+typedef struct {
+    uint64_t tai64;      /* TAI64 timestamp (8 bytes) */
+    uint32_t nanosec;    /* Nanoseconds (4 bytes) */
+} __attribute__((packed)) tai64n_t;
+
+/**
+ * @brief Encode current time as TAI64N
+ * @param out Output buffer (12 bytes)
+ * @return 0 on success, -1 on error
+ */
+int se050_tai64n_now(uint8_t out[TAI64N_SIZE]);
+
+/**
+ * @brief Encode a TAI64N timestamp
+ * @param out Output buffer (12 bytes)
+ * @param seconds Unix timestamp (seconds since 1970-01-01)
+ * @param nanoseconds Nanoseconds (0-999999999)
+ * @return 0 on success, -1 on error
+ */
+int se050_tai64n_encode(uint8_t out[TAI64N_SIZE],
+                        uint64_t seconds, uint32_t nanoseconds);
+
+/**
+ * @brief Decode a TAI64N timestamp
+ * @param seconds Output Unix timestamp (seconds)
+ * @param nanoseconds Output nanoseconds
+ * @param in Input buffer (12 bytes)
+ * @return 0 on success, -1 on error
+ */
+int se050_tai64n_decode(uint64_t *seconds, uint32_t *nanoseconds,
+                        const uint8_t in[TAI64N_SIZE]);
+
+/**
+ * @brief Check if TAI64N timestamp is within acceptable window
+ * @param timestamp Timestamp to check
+ * @param window_sec Acceptable window in seconds
+ * @return 0 if within window, -1 if too old, -2 if too far in future
+ */
+int se050_tai64n_check_window(const uint8_t timestamp[TAI64N_SIZE],
+                              uint32_t window_sec);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SE050_TAI64N_H */