Update kernel module parameters

README.md

@@ -183,9 +183,8 @@ Available flags:
 
 - `--fake-sni-seq-len=<length>` This flag specifies **youtubeUnblock** to build a complicated construction of fake client hello packets. length determines how much fakes will be sent. Defaults to **1**.
 
-- `--fake-sni-type={default|custom|random}` This flag specifies which faking messages should use fake packets. If you pass random, the message of random length and random payload will be sent. For default the default payload is used. And for custom the payload from `--fake-custom-payload` is used. Default to `default`.
+- `--fake-sni-type={default|custom|random}` This flag specifies which faking message type should be used for fake packets. For `random`, the message of random length and with random payload will be sent. For `default` the default payload (sni=www.google.com) is used. And for the `custom` option, the payload from `--fake-custom-payload` section utilized. Defaults to `default`.
-
+- `--fake-custom-payload=<payload>` Useful with `--fake-sni-type=custom`. You should specify the payload for fake message manually. Use hex format: `--fake-custom-payload=0001020304` mean that 5 bytes sequence: `0x00`, `0x01`, `0x02`, `0x03`, `0x04` used as fake.
-- `--fake-custom-payload=<payload>` Usable with `--fake-sni-type=custom`. You should specify the payload for fake message manually. Use hex format: `--fake-custom-payload=0001020304` mean that 5 bytes sequence: `0x00`, `0x01`, `0x02`, `0x03`, `0x04` used as fake.
 
 - `--faking-strategy={randseq|ttl|tcp_check|pastseq|md5sum}` This flag determines the strategy of fake packets invalidation. Defaults to `randseq`
   - `randseq` specifies that random sequence/acknowledgemend random will be set. This option may be handled by provider which uses *conntrack* with drop on invalid *conntrack* state firewall rule enabled. 

kargs.c

@@ -125,6 +125,7 @@ module_param_cb(fk_winsize, &unumeric_parameter_ops, &config.fk_winsize, 0664);
 module_param_cb(synfake, &boolean_parameter_ops, &config.synfake, 0664);
 module_param_cb(synfake_len, &unumeric_parameter_ops, &config.synfake_len, 0664);
 module_param_cb(packet_mark, &unumeric_parameter_ops, &config.mark, 0664);
+// module_param_cb(seg2delay, &unumeric_parameter_ops, &config.seg2_delay, 0664);
 
 static int sni_domains_set(const char *val, const struct kernel_param *kp) {
 	size_t len;
@@ -404,3 +405,110 @@ static const struct kernel_param_ops sni_detection_ops = {
 };
 
 module_param_cb(sni_detection, &sni_detection_ops, &config.sni_detection, 0664);
+
+static int fake_type_set(const char *val, const struct kernel_param *kp) {
+	size_t len;
+
+	len = strnlen(val, STR_MAXLEN + 1);
+	if (len == STR_MAXLEN + 1) {
+		pr_err("%s: string parameter too long\n", kp->name);
+		return -ENOSPC;
+	}
+
+	if (len >= 1 && val[len - 1] == '\n') {
+		len--;
+	}
+
+	if (strncmp(val, "default", len) == 0) {
+		*(int *)kp->arg = FAKE_PAYLOAD_DEFAULT;
+	} else if (strncmp(val, "custom", len) == 0) {
+		*(int *)kp->arg = FAKE_PAYLOAD_CUSTOM;
+	} else if (strncmp(val, "random", len) == 0) {
+		*(int *)kp->arg = FAKE_PAYLOAD_RANDOM;
+	} else {
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int fake_type_get(char *buffer, const struct kernel_param *kp) {
+	switch (*(int *)kp->arg) {
+		case FAKE_PAYLOAD_DEFAULT:
+			strcpy(buffer, "default\n");
+			break;
+		case FAKE_PAYLOAD_RANDOM:
+			strcpy(buffer, "random\n");
+			break;
+		case FAKE_PAYLOAD_CUSTOM:
+			strcpy(buffer, "custom\n");
+			break;
+		default:
+			strcpy(buffer, "unknown\n");
+	}
+
+	return strlen(buffer);
+}
+
+static const struct kernel_param_ops fake_type_ops = {
+	.set = fake_type_set,
+	.get = fake_type_get,
+};
+
+module_param_cb(fake_sni_type, &fake_type_ops, &config.fake_sni_type, 0664);
+
+static int fake_custom_pl_set(const char *val, const struct kernel_param *kp) {
+	size_t len;
+
+	len = strnlen(val, STR_MAXLEN + 1);
+	if (len == STR_MAXLEN + 1) {
+		pr_err("%s: string parameter too long\n", kp->name);
+		return -ENOSPC;
+	}
+
+	if (len >= 1 && val[len - 1] == '\n') {
+		len--;
+	}
+
+	uint8_t *const custom_buf = (uint8_t *)custom_fake_buf;
+	const char *custom_hex_fake = val;
+	size_t custom_hlen = len;
+
+	if ((custom_hlen & 1) == 1) {
+		return -EINVAL;
+	}
+
+
+	size_t custom_len = custom_hlen >> 1;
+	if (custom_len > MAX_FAKE_SIZE) {
+		return -EINVAL;
+	}
+
+	for (int i = 0; i < custom_len; i++) {
+		sscanf(custom_hex_fake + (i << 1), "%2hhx", custom_buf + i);
+	}
+
+	config.fake_custom_pkt_sz = custom_len;
+	config.fake_custom_pkt = (char *)custom_buf;
+
+	return 0;
+}
+
+static int fake_custom_pl_get(char *buffer, const struct kernel_param *kp) {
+	int cflen = config.fake_custom_pkt_sz;
+	const uint8_t *cbf_data = config.fake_custom_pkt;
+	int bflen = config.fake_custom_pkt_sz << 1;
+
+	for (int i = 0; i < cflen; i++) {
+		sprintf(buffer + (i << 1), "%02x", *((unsigned char *)cbf_data + i));
+	}
+
+	return bflen;
+}
+
+static const struct kernel_param_ops fake_custom_pl_ops = {
+	.set = fake_custom_pl_set,
+	.get = fake_custom_pl_get,
+};
+
+module_param_cb(fake_custom_payload, &fake_custom_pl_ops, &config.fake_custom_pkt, 0664);