Add support KCP protocol

https://github.com/skywind3000/kcp/blob/master/README.en.md

Signed-off-by: Jianhui Zhao <zhaojh329@gmail.com>

Author: zhaojh329

.gitmodules

@@ -7,3 +7,6 @@
 [submodule "src/log"]
 	path = src/log
 	url = https://github.com/zhaojh329/log.git
+[submodule "src/kcp"]
+	path = src/kcp
+	url = https://github.com/skywind3000/kcp.git

src/CMakeLists.txt

@@ -3,25 +3,43 @@ set(RTTY_VERSION_MAJOR 9)
 set(RTTY_VERSION_MINOR 0)
 set(RTTY_VERSION_PATCH 2)
 
+option(KCP_SUPPORT "KCP support" ON)
+
 # Check the third party Libraries
 find_package(Libev REQUIRED)
 
-aux_source_directory(. SRCS)
 aux_source_directory(log SRCS)
 aux_source_directory(buffer SRCS)
 
+add_subdirectory(ssl)
+
+list(APPEND SRCS main.c rtty.c net.c utils.c file.c filectl.c command.c http.c)
+
+if(KCP_SUPPORT)
+    if (NOT SSL_SUPPORT)
+        message(WARNING "SSL Not enabled, disable KCP")
+        set(KCP_SUPPORT OFF)
+    else()
+        list(APPEND SRCS kcp.c crc32.c crypt.c)
+    endif()
+endif()
+
 add_executable(rtty ${SRCS})
 target_compile_definitions(rtty PRIVATE _GNU_SOURCE)
 target_compile_options(rtty PRIVATE -O -Wall -Werror --std=gnu99)
 target_include_directories(rtty PRIVATE ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/buffer ${LIBEV_INCLUDE_DIR})
 target_link_libraries(rtty PRIVATE ${LIBEV_LIBRARY} util crypt m)
 
-add_subdirectory(ssl)
-
 if(SSL_SUPPORT)
+    target_compile_definitions(rtty PRIVATE ${SSL_DEFINE})
     target_link_libraries(rtty PRIVATE ${SSL_TARGET})
 endif()
 
+if(KCP_SUPPORT)
+    add_subdirectory(kcp)
+    target_link_libraries(rtty PRIVATE kcp)
+endif()
+
 # configure a header file to pass some of the CMake settings to the source code
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/config.h.in ${CMAKE_CURRENT_BINARY_DIR}/config.h)
 

src/config.h.in

@@ -31,5 +31,6 @@
 #define RTTY_VERSION_STRING "@RTTY_VERSION_MAJOR@.@RTTY_VERSION_MINOR@.@RTTY_VERSION_PATCH@"
 
 #cmakedefine SSL_SUPPORT
+#cmakedefine KCP_SUPPORT
 
 #endif

src/crc32.c

@@ -0,0 +1,120 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2019 Jianhui Zhao <zhaojh329@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdint.h>
+
+#define IEEE 0xedb88320
+
+#define slicing8_cutoff 16
+
+typedef uint32_t table[256];
+
+typedef struct slicing8_table {
+    table tables[8];
+} slicing8_table;
+
+static slicing8_table tab;
+
+static void simple_populate_table(uint32_t poly, table t)
+{
+    int i, j;
+
+    for (i = 0; i < 256; i++) {
+        uint32_t crc = i;
+        for (j = 0; j < 8; j++) {
+            if (crc & 1) {
+                crc = (crc >> 1) ^ poly;
+            } else {
+                crc >>= 1;
+            }
+        }
+        t[i] = crc;
+    }
+}
+
+static void slicing_make_table(uint32_t poly)
+{
+    int i, j;
+
+    simple_populate_table(poly, tab.tables[0]);
+
+    for (i = 0; i < 256; i++) {
+        uint32_t crc = tab.tables[0][i];
+        for (j = 1; j < 8; j++) {
+            crc = tab.tables[0][crc & 0xFF] ^ (crc >> 8);
+            tab.tables[j][i] = crc;
+        }
+    }
+}
+
+static uint32_t simple_update(uint32_t crc, const table tab, const uint8_t *p, size_t len)
+{
+    size_t i;
+
+    crc = ~crc;
+
+    for (i = 0; i < len; i++)
+        crc = tab[(uint8_t)crc ^ p[i]] ^ (crc >> 8);
+
+    return ~crc;
+}
+
+uint32_t crc32_checksum_ieee(const uint8_t* p, size_t len)
+{
+    static bool inited;
+    uint32_t crc = 0;
+
+    if (!inited) {
+        inited = true;
+        slicing_make_table(IEEE);
+    }
+
+    if (len >= slicing8_cutoff) {
+        crc = ~crc;
+        while (len >= 8) {
+            uint32_t n;
+            memcpy(&n, p, sizeof(n));
+            crc ^= n;
+            crc = tab.tables[0][p[7]] ^
+                  tab.tables[1][p[6]] ^
+                  tab.tables[2][p[5]] ^
+                  tab.tables[3][p[4]] ^
+                  tab.tables[4][crc >> 24] ^
+                  tab.tables[5][(crc >> 16) & 0xFF] ^
+                  tab.tables[6][(crc >> 8) & 0xFF] ^
+                  tab.tables[7][crc & 0xFF];
+            p += 8;
+            len -= 8;
+        }
+        crc = ~crc;
+    }
+
+    if (len == 0)
+        return crc;
+
+    return simple_update(crc, tab.tables[0], p, len);
+}

src/crc32.h

@@ -0,0 +1,33 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2019 Jianhui Zhao <zhaojh329@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef RTTY_CRC32_H
+#define RTTY_CRC32_H
+
+#include <sys/types.h>
+#include <stdint.h>
+
+uint32_t crc32_checksum_ieee(const uint8_t *p, size_t len);
+
+#endif