1 files changed, 120 insertions, 0 deletions
diff --git a/src/aclk/mqtt_websockets/ws_client.h b/src/aclk/mqtt_websockets/ws_client.h
new file mode 100644
index 000000000..0ccbd29a8
--- /dev/null
+++ b/src/aclk/mqtt_websockets/ws_client.h
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-3.0-only
+// Copyright (C) 2020 Timotej Šiškovič
+
+#ifndef WS_CLIENT_H
+#define WS_CLIENT_H
+
+#include "c-rbuf/cringbuffer.h"
+#include "mqtt_wss_log.h"
+
+#include <stdint.h>
+
+#define WS_CLIENT_NEED_MORE_BYTES     0x10
+#define WS_CLIENT_PARSING_DONE        0x11
+#define WS_CLIENT_CONNECTION_CLOSED   0x12
+#define WS_CLIENT_PROTOCOL_ERROR     -0x10
+#define WS_CLIENT_BUFFER_FULL        -0x11
+#define WS_CLIENT_INTERNAL_ERROR     -0x12
+
+enum websocket_client_conn_state {
+    WS_RAW = 0,
+    WS_HANDSHAKE,
+    WS_ESTABLISHED,
+    WS_ERROR,        // connection has to be restarted if this is reached
+    WS_CONN_CLOSED_GRACEFUL
+};
+
+enum websocket_client_hdr_parse_state {
+    WS_HDR_HTTP = 0,        // need to check HTTP/1.1
+    WS_HDR_RC,              // need to read HTTP code
+    WS_HDR_ENDLINE,         // need to read rest of the first line
+    WS_HDR_PARSE_HEADERS,   // rest of the header until CRLF CRLF
+    WS_HDR_PARSE_DONE,
+    WS_HDR_ALL_DONE
+};
+
+enum websocket_client_rx_ws_parse_state {
+    WS_FIRST_2BYTES = 0,
+    WS_PAYLOAD_EXTENDED_16,
+    WS_PAYLOAD_EXTENDED_64,
+    WS_PAYLOAD_DATA, // BINARY payload to be passed to MQTT
+    WS_PAYLOAD_CONNECTION_CLOSE,
+    WS_PAYLOAD_CONNECTION_CLOSE_EC,
+    WS_PAYLOAD_CONNECTION_CLOSE_MSG,
+    WS_PAYLOAD_SKIP_UNKNOWN_PAYLOAD,
+    WS_PAYLOAD_PING_REQ_PAYLOAD, // PING payload to be sent back as PONG
+    WS_PACKET_DONE
+};
+
+enum websocket_opcode {
+    WS_OP_CONTINUATION_FRAME = 0x0,
+    WS_OP_TEXT_FRAME         = 0x1,
+    WS_OP_BINARY_FRAME       = 0x2,
+    WS_OP_CONNECTION_CLOSE   = 0x8,
+    WS_OP_PING               = 0x9,
+    WS_OP_PONG               = 0xA
+};
+
+struct ws_op_close_payload {
+    uint16_t ec;
+    char *reason;
+};
+
+struct http_header {
+    char *key;
+    char *value;
+    struct http_header *next;
+};
+
+typedef struct websocket_client {
+    enum websocket_client_conn_state state;
+
+    struct ws_handshake {
+        enum websocket_client_hdr_parse_state hdr_state;
+        char *nonce_reply;
+        int nonce_matched;
+        int http_code;
+        char *http_reply_msg;
+        struct http_header *headers;
+        struct http_header *headers_tail;
+        int hdr_count;
+    } hs;
+
+    struct ws_rx {
+        enum websocket_client_rx_ws_parse_state parse_state;
+        enum websocket_opcode opcode;
+        uint64_t payload_length;
+        uint64_t payload_processed;
+        union {
+            struct ws_op_close_payload op_close;
+            char *ping_msg;
+        } specific_data;
+    } rx;
+
+    rbuf_t buf_read;    // from SSL
+    rbuf_t buf_write;   // to SSL and then to socket
+    // TODO if ringbuffer gets multiple tail support
+    // we can work without buf_to_mqtt and thus reduce
+    // memory usage and remove one more memcpy buf_read->buf_to_mqtt
+    rbuf_t buf_to_mqtt; // RAW data for MQTT lib
+
+    int entropy_fd;
+
+    // careful host is borrowed, don't free
+    char **host;
+    mqtt_wss_log_ctx_t log;
+} ws_client;
+
+ws_client *ws_client_new(size_t buf_size, char **host, mqtt_wss_log_ctx_t log);
+void ws_client_destroy(ws_client *client);
+void ws_client_reset(ws_client *client);
+
+int ws_client_start_handshake(ws_client *client);
+
+int ws_client_want_write(ws_client *client);
+
+int ws_client_process(ws_client *client);
+
+int ws_client_send(ws_client *client, enum websocket_opcode frame_type, const char *data, size_t size);
+
+#endif /* WS_CLIENT_H */