Restructure hasher implementation

src/base/hash/hasher/siphash.c

@@ -5,10 +5,11 @@
 #include "../../../common/aliases/aliases.h"
 #include "../../../common/assert/assert.h"
 #include "../../../common/misc/misc_utils.h"
+#include "../../../prng/xorshift/xorshift.h"
 
-wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8 *out, u64 outlen);
-wp_intern inline void validateSipHasherCtx(const WpSipHasherCtx *io);
-wp_intern inline b8 checkRounds(const WpSipHasherCtx *params);
+wp_intern inline void siphash(WpStream *bytes, const WpHasherCtx *ctx, u8 *out, u64 outlen);
+wp_intern inline void validateSipHasherCtx(const WpHasherCtx *ctx);
+wp_intern inline b8 checkRounds(const WpHasherCtx *ctx);
 
 #define _u32To8LE(p, v)                                                                            \
 	(p)[0] = (u8)((v));                                                                              \
@@ -44,24 +45,50 @@ wp_intern inline b8 checkRounds(const WpSipHasherCtx *params);
 		v2 = wpMiscUtilsRotl64(v2, 32);                                                                \
 	} while (0)
 
-WpHasher wpSipHasher(WpSipHasherCtx *data) {
-	return (WpHasher){ .func = wpSipHasher128, .data = (void *)data };
+WpHasher wpSip24Hasher(void) {
+	WpXor256State state = wpPrngXorshiftInit();
+	WpU128 key          = { .value = { wpPrngXorshift256(&state), wpPrngXorshift256(&state) } };
+	return wpSip24HasherWithKey(key);
 }
 
-WpU128Hash wpSipHasher128(WpStream *bytes, void *hasher_data) {
-	WpSipHasherCtx *data = (WpSipHasherCtx *)hasher_data;
-	validateSipHasherCtx(data);
-	WpU128Hash output = {0};
-	siphash(bytes, data, (u8 *)&output.hash, sizeof(u64) * 2);
+WpHasher wpSip48Hasher(void) {
+	WpXor256State state = wpPrngXorshiftInit();
+	WpU128 key          = { .value = { wpPrngXorshift256(&state), wpPrngXorshift256(&state) } };
+	return wpSip48HasherWithKey(key);
+}
+
+WpHasher wpSip24HasherWithKey(WpU128 key) {
+	return (WpHasher){
+		.func = wpSipGetHash128,
+		.ctx  = (WpHasherCtx){
+			.type    = WP_HASHER_CTX_SIPHASH,
+			.siphash = (WpSiphashCtx){ .key = key, .compression = 2, .finalisation = 4 },
+		},
+	};
+}
+
+WpHasher wpSip48HasherWithKey(WpU128 key) {
+	return (WpHasher){
+		.func = wpSipGetHash128,
+		.ctx  = (WpHasherCtx){
+			.type    = WP_HASHER_CTX_SIPHASH,
+			.siphash = (WpSiphashCtx){ .key = key, .compression = 4, .finalisation = 8 },
+		},
+	};
+}
+
+WpU128 wpSipGetHash128(WpStream *bytes, WpHasherCtx ctx) {
+	validateSipHasherCtx(&ctx);
+	WpU128 output = {0};
+	siphash(bytes, &ctx, (u8 *)&output.value, sizeof(u64) * 2);
 	return output;
 }
 
 /**
  * Implementation of the 128-variant of the siphash algorithm
  */
-wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8 *out,
-                              u64 outlen) {
-	const u8 *kk = (const u8 *)&params->key;
+wp_intern inline void siphash(WpStream *bytes, const WpHasherCtx *ctx, u8 *out, u64 outlen) {
+	const u8 *kk = (const u8 *)&ctx->siphash.key;
 	u64 inlen    = bytes->count * bytes->item_size;
 
 	wpRuntimeAssert(outlen == 16, "outlen should be 16");
@@ -89,7 +116,7 @@ wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8
 		m = _u8To64LE(data);
 		v3 ^= m;
 
-		for (i = 0; i < params->compression; ++i) {
+		for (i = 0; i < ctx->siphash.compression; ++i) {
 			_sipRound;
 		}
 
@@ -125,7 +152,7 @@ wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8
 
 	v3 ^= b;
 
-	for (i = 0; i < params->compression; ++i) {
+	for (i = 0; i < ctx->siphash.compression; ++i) {
 		_sipRound;
 	}
 
@@ -133,7 +160,7 @@ wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8
 
 	v2 ^= 0xee;
 
-	for (i = 0; i < params->finalisation; ++i) {
+	for (i = 0; i < ctx->siphash.finalisation; ++i) {
 		_sipRound;
 	}
 
@@ -142,7 +169,7 @@ wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8
 
 	v1 ^= 0xdd;
 
-	for (i = 0; i < params->finalisation; ++i) {
+	for (i = 0; i < ctx->siphash.finalisation; ++i) {
 		_sipRound;
 	}
 
@@ -150,14 +177,14 @@ wp_intern inline void siphash(WpStream *bytes, const WpSipHasherCtx *params, u8
 	_u64To8LE(out + 8, b);
 }
 
-wp_intern inline void validateSipHasherCtx(const WpSipHasherCtx *ctx) {
-	b8 magic_match = ctx->magic == WP_SIP_HASHER_MAGIC;
+wp_intern inline void validateSipHasherCtx(const WpHasherCtx *ctx) {
+	b8 magic_match = ctx->type == WP_HASHER_CTX_SIPHASH;
 	b8 rounds      = checkRounds(ctx);
 	wpRuntimeAssert(magic_match && rounds, "Invalid Siphash context");
 }
 
-wp_intern inline b8 checkRounds(const WpSipHasherCtx *ctx) {
-	b8 rounds24 = ctx->compression == 2 && ctx->finalisation == 4;
-	b8 rounds48 = ctx->compression == 4 && ctx->finalisation == 8;
+wp_intern inline b8 checkRounds(const WpHasherCtx *ctx) {
+	b8 rounds24 = ctx->siphash.compression == 2 && ctx->siphash.finalisation == 4;
+	b8 rounds48 = ctx->siphash.compression == 4 && ctx->siphash.finalisation == 8;
 	return rounds24 || rounds48;
 }