[Feature] Add more algorithms for shingles generation

src/libutil/shingles.c

@@ -24,7 +24,8 @@ rspamd_shingles_generate (GArray *input,
 		const guchar key[16],
 		rspamd_mempool_t *pool,
 		rspamd_shingles_filter filter,
-		gpointer filterd)
+		gpointer filterd,
+		enum rspamd_shingle_alg alg)
 {
 	struct rspamd_shingle *res;
 	GArray *hashes[RSPAMD_SHINGLE_SIZE];
@@ -35,7 +36,8 @@ rspamd_shingles_generate (GArray *input,
 	rspamd_ftok_t *word;
 	rspamd_cryptobox_hash_state_t bs;
 	guint64 val;
-	gint i, j, beg = 0;
+	gint i, j, k, beg = 0;
+	enum rspamd_cryptobox_fast_hash_type ht;
 
 	if (pool != NULL) {
 		res = rspamd_mempool_alloc (pool, sizeof (*res));
@@ -71,22 +73,64 @@ rspamd_shingles_generate (GArray *input,
 	}
 
 	/* Now parse input words into a vector of hashes using rolling window */
-	for (i = 0; i <= (gint)input->len; i ++) {
-		if (i - beg >= SHINGLES_WINDOW || i == (gint)input->len) {
-			for (j = beg; j < i; j ++) {
-				word = &g_array_index (input, rspamd_ftok_t, j);
-				row = rspamd_fstring_append (row, word->begin, word->len);
+	if (alg == RSPAMD_SHINGLES_OLD) {
+		for (i = 0; i <= (gint)input->len; i ++) {
+			if (i - beg >= SHINGLES_WINDOW || i == (gint)input->len) {
+				for (j = beg; j < i; j ++) {
+					word = &g_array_index (input, rspamd_ftok_t, j);
+					row = rspamd_fstring_append (row, word->begin, word->len);
+				}
+				beg++;
+
+				/* Now we need to create a new row here */
+				for (j = 0; j < RSPAMD_SHINGLE_SIZE; j ++) {
+					rspamd_cryptobox_siphash ((guchar *)&val, row->str, row->len,
+							keys[j]);
+					g_array_append_val (hashes[j], val);
+				}
+
+				row = rspamd_fstring_assign (row, "", 0);
 			}
-			beg++;
+		}
+	}
+	else {
+		guint64 res[SHINGLES_WINDOW * RSPAMD_SHINGLE_SIZE];
 
-			/* Now we need to create a new row here */
-			for (j = 0; j < RSPAMD_SHINGLE_SIZE; j ++) {
-				rspamd_cryptobox_siphash ((guchar *)&val, row->str, row->len,
-						keys[j]);
-				g_array_append_val (hashes[j], val);
-			}
+		if (alg == RSPAMD_SHINGLES_XXHASH) {
+			ht = RSPAMD_CRYPTOBOX_XXHASH64;
+		}
+		else {
+			ht = RSPAMD_CRYPTOBOX_MUMHASH;
+		}
 
-			row = rspamd_fstring_assign (row, "", 0);
+		memset (res, 0, sizeof (res));
+
+		for (i = 0; i <= (gint)input->len; i ++) {
+			if (i - beg >= SHINGLES_WINDOW || i == (gint)input->len) {
+
+				for (j = 0; j < RSPAMD_SHINGLE_SIZE; j ++) {
+					/* Shift hashes window to right */
+					for (k = 0; k < SHINGLES_WINDOW - 1; k ++) {
+						res[j * SHINGLES_WINDOW + k] =
+								res[j * SHINGLES_WINDOW + k + 1];
+					}
+
+					word = &g_array_index (input, rspamd_ftok_t, beg);
+					/* Insert the last element to the pipe */
+					res[j * SHINGLES_WINDOW + SHINGLES_WINDOW - 1] =
+							rspamd_cryptobox_fast_hash_specific (ht,
+									word->begin, word->len,
+									*(guint64 *)keys[j]);
+
+					val = 0;
+					for (k = 0; k < SHINGLES_WINDOW; k ++) {
+						val ^= res[j * SHINGLES_WINDOW + k];
+					}
+
+					g_array_append_val (hashes[j], val);
+				}
+				beg++;
+			}
 		}
 	}
 

src/libutil/shingles.h

@@ -25,6 +25,12 @@ struct rspamd_shingle {
 	guint64 hashes[RSPAMD_SHINGLE_SIZE];
 };
 
+enum rspamd_shingle_alg {
+	RSPAMD_SHINGLES_OLD = 0,
+	RSPAMD_SHINGLES_XXHASH,
+	RSPAMD_SHINGLES_MUMHASH,
+};
+
 /**
  * Shingles filtering function
  * @param input input array of hashes
@@ -48,7 +54,8 @@ struct rspamd_shingle* rspamd_shingles_generate (GArray *input,
 		const guchar key[16],
 		rspamd_mempool_t *pool,
 		rspamd_shingles_filter filter,
-		gpointer filterd);
+		gpointer filterd,
+		enum rspamd_shingle_alg alg);
 
 /**
  * Compares two shingles and return result as a floating point value - 1.0

src/plugins/fuzzy_check.c

@@ -1068,7 +1068,8 @@ fuzzy_cmd_from_text_part (struct fuzzy_rule *rule,
 			rule->shingles_key->str);
 	sh = rspamd_shingles_generate (words,
 			rule->shingles_key->str, pool,
-			rspamd_shingles_default_filter, NULL);
+			rspamd_shingles_default_filter, NULL,
+			RSPAMD_SHINGLES_OLD);
 	if (sh != NULL) {
 		memcpy (&shcmd->sgl, sh, sizeof (shcmd->sgl));
 		shcmd->basic.shingles_count = RSPAMD_SHINGLE_SIZE;

test/rspamd_shingles_test.c

@@ -81,7 +81,8 @@ free_fuzzy_words (GArray *ar)
 }
 
 static void
-test_case (gsize cnt, gsize max_len, gdouble perm_factor)
+test_case (gsize cnt, gsize max_len, gdouble perm_factor,
+		enum rspamd_shingle_alg alg)
 {
 	GArray *input;
 	struct rspamd_shingle *sgl, *sgl_permuted;
@@ -93,17 +94,18 @@ test_case (gsize cnt, gsize max_len, gdouble perm_factor)
 	input = generate_fuzzy_words (cnt, max_len);
 	ts1 = rspamd_get_ticks ();
 	sgl = rspamd_shingles_generate (input, key, NULL,
-			rspamd_shingles_default_filter, NULL);
+			rspamd_shingles_default_filter, NULL, alg);
 	ts2 = rspamd_get_ticks ();
 	permute_vector (input, perm_factor);
 	sgl_permuted = rspamd_shingles_generate (input, key, NULL,
-			rspamd_shingles_default_filter, NULL);
+			rspamd_shingles_default_filter, NULL, alg);
 
 	res = rspamd_shingles_compare (sgl, sgl_permuted);
 
-	msg_debug ("percentage of common shingles: %.3f, generate time: %hd usec",
-			res, (gint)(ts1 - ts2) * 1000);
-	g_assert_cmpfloat (fabs ((1.0 - res) - sqrt (perm_factor)), <=, 0.20);
+	msg_info ("%d (%z words of %z max len, %.2f perm factor):"
+			" percentage of common shingles: %.3f, generate time: %.4f sec",
+			alg, cnt, max_len, perm_factor, res, ts2 - ts1);
+	g_assert_cmpfloat (fabs ((1.0 - res) - sqrt (perm_factor)), <=, 0.25);
 
 	free_fuzzy_words (input);
 	g_free (sgl);
@@ -113,10 +115,15 @@ test_case (gsize cnt, gsize max_len, gdouble perm_factor)
 void
 rspamd_shingles_test_func (void)
 {
-	//test_case (5, 100, 0.5);
-	test_case (200, 10, 0.1);
-	test_case (500, 20, 0.01);
-	test_case (5000, 20, 0.01);
-	test_case (5000, 15, 0);
-	test_case (5000, 30, 1.0);
+	enum rspamd_shingle_alg alg = RSPAMD_SHINGLES_OLD;
+
+	for (alg = RSPAMD_SHINGLES_OLD; alg <= RSPAMD_SHINGLES_MUMHASH; alg ++) {
+		test_case (200, 10, 0.1, alg);
+		test_case (500, 20, 0.01, alg);
+		test_case (5000, 20, 0.01, alg);
+		test_case (5000, 15, 0, alg);
+		test_case (5000, 30, 1.0, alg);
+		test_case (50000, 30, 0.02, alg);
+		test_case (50000, 5, 0.02, alg);
+	}
 }