use libev instead of libuv

1 files changed, 238 insertions, 1 deletions

diff --git a/dnsudp2tcp.c b/dnsudp2tcp.c
index 30c3e8a..85491bf 100644
--- a/dnsudp2tcp.c
+++ b/dnsudp2tcp.c
@@ -17,4 +17,241 @@
 #include "libev/ev.h"
 #undef _GNU_SOURCE
 
-// TODO
+#define DNS2TCP_VER "dns2tcp v1.1.0"
+
+#define IP4STRLEN INET_ADDRSTRLEN /* ipv4addr max strlen */
+#define IP6STRLEN INET6_ADDRSTRLEN /* ipv6addr max strlen */
+#define PORTSTRLEN 6 /* "65535", include the null character */
+#define UDPDGRAM_MAXSIZ 1472 /* mtu:1500 - iphdr:20 - udphdr:8 */
+
+typedef uint16_t portno_t; /* 16bit */
+typedef struct sockaddr_in  skaddr4_t;
+typedef struct sockaddr_in6 skaddr6_t;
+
+#define IF_VERBOSE if (g_verbose)
+
+#define LOGINF(fmt, ...)                                                    \
+    do {                                                                    \
+        struct tm *tm = localtime(&(time_t){time(NULL)});                   \
+        printf("\e[1;32m%04d-%02d-%02d %02d:%02d:%02d INF:\e[0m " fmt "\n", \
+                tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,            \
+                tm->tm_hour,        tm->tm_min,     tm->tm_sec,             \
+                ##__VA_ARGS__);                                             \
+    } while (0)
+
+#define LOGERR(fmt, ...)                                                    \
+    do {                                                                    \
+        struct tm *tm = localtime(&(time_t){time(NULL)});                   \
+        printf("\e[1;35m%04d-%02d-%02d %02d:%02d:%02d ERR:\e[0m " fmt "\n", \
+                tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,            \
+                tm->tm_hour,        tm->tm_min,     tm->tm_sec,             \
+                ##__VA_ARGS__);                                             \
+    } while (0)
+
+typedef struct {
+    evio_t    watcher;
+    void     *buffer;
+    uint16_t  nrecv;
+    skaddr6_t srcaddr;
+} tcpwatcher_t;
+
+enum {
+    OPT_REUSE_PORT = 1 << 0,
+    OPT_QUICK_ACK  = 1 << 1,
+    OPT_FAST_OPEN  = 1 << 2,
+};
+
+static bool       g_verbose                 = false;
+static uint8_t    g_options                 = 0;
+static uint8_t    g_syn_maxcnt              = 0;
+static evloop_t  *g_event_loop              = NULL;
+static evio_t     g_udp_watcher             = {0};
+static char       g_listen_ipstr[IP6STRLEN] = {0};
+static portno_t   g_listen_portno           = 0;
+static skaddr6_t  g_listen_skaddr           = {0};
+static char       g_remote_ipstr[IP6STRLEN] = {0};
+static portno_t   g_remote_portno           = 0;
+static skaddr6_t  g_remote_skaddr           = {0};
+
+static void udp_recv_cb(evloop_t *evloop, evio_t *watcher, int events);
+static void tcp_send_cb(evloop_t *evloop, evio_t *watcher, int events);
+static void tcp_recv_cb(evloop_t *evloop, evio_t *watcher, int events);
+
+static int get_ipstr_family(const char *ipstr) {
+    if (!ipstr) return -1; /* invalid */
+    uint8_t ipaddr[16]; /* 16-bytes */
+    if (inet_pton(AF_INET, ipstr, &ipaddr) == 1) {
+        return AF_INET;
+    } else if (inet_pton(AF_INET6, ipstr, &ipaddr) == 1) {
+        return AF_INET6;
+    } else {
+        return -1; /* invalid */
+    }
+}
+
+static void build_sock_addr4(skaddr4_t *addr, const char *ipstr, portno_t portno) {
+    addr->sin_family = AF_INET;
+    inet_pton(AF_INET, ipstr, &addr->sin_addr);
+    addr->sin_port = htons(portno);
+}
+static void build_sock_addr6(skaddr6_t *addr, const char *ipstr, portno_t portno) {
+    addr->sin6_family = AF_INET6;
+    inet_pton(AF_INET6, ipstr, &addr->sin6_addr);
+    addr->sin6_port = htons(portno);
+}
+
+static void parse_sock_addr4(const skaddr4_t *addr, char *ipstr, portno_t *portno) {
+    inet_ntop(AF_INET, &addr->sin_addr, ipstr, IP4STRLEN);
+    *portno = ntohs(addr->sin_port);
+}
+static void parse_sock_addr6(const skaddr6_t *addr, char *ipstr, portno_t *portno) {
+    inet_ntop(AF_INET6, &addr->sin6_addr, ipstr, IP6STRLEN);
+    *portno = ntohs(addr->sin6_port);
+}
+
+static void print_command_help(void) {
+    printf("usage: dns2tcp <-L listen> <-R remote> [-s syncnt] [-rafvVh]\n"
+           " -L <ip#port>           udp listen address, this is required\n"
+           " -R <ip#port>           tcp remote address, this is required\n"
+           " -s <syncnt>            set TCP_SYNCNT(max) for remote socket\n"
+           " -r                     enable SO_REUSEPORT for listen socket\n"
+           " -a                     enable TCP_QUICKACK for remote socket\n"
+           " -f                     enable TCP_FASTOPEN for remote socket\n"
+           " -v                     print verbose log, default: <disabled>\n"
+           " -V                     print version number of dns2tcp and exit\n"
+           " -h                     print help information of dns2tcp and exit\n"
+           "bug report: https://github.com/zfl9/dns2tcp. email: zfl9.com@gmail.com\n"
+    );
+}
+
+static void parse_address_opt(char *ip_port_str, bool is_listen_addr) {
+    const char *opt_name = is_listen_addr ? "listen" : "remote";
+
+    char *portstr = strchr(ip_port_str, '#');
+    if (!portstr) {
+        printf("[parse_address_opt] %s port is not specified\n", opt_name);
+        goto PRINT_HELP_AND_EXIT;
+    }
+    if (portstr == ip_port_str) {
+        printf("[parse_address_opt] %s addr is not specified\n", opt_name);
+        goto PRINT_HELP_AND_EXIT;
+    }
+
+    *portstr = 0; ++portstr;
+    if (strlen(portstr) + 1 > PORTSTRLEN) {
+        printf("[parse_address_opt] %s port is invalid: %s\n", opt_name, portstr);
+        goto PRINT_HELP_AND_EXIT;
+    }
+    portno_t portno = strtoul(portstr, NULL, 10);
+    if (portno == 0) {
+        printf("[parse_address_opt] %s port is invalid: %s\n", opt_name, portstr);
+        goto PRINT_HELP_AND_EXIT;
+    }
+
+    char *ipstr = ip_port_str;
+    if (strlen(ipstr) + 1 > IP6STRLEN) {
+        printf("[parse_address_opt] %s addr is invalid: %s\n", opt_name, ipstr);
+        goto PRINT_HELP_AND_EXIT;
+    }
+    int ipfamily = get_ipstr_family(ipstr);
+    if (ipfamily == -1) {
+        printf("[parse_address_opt] %s addr is invalid: %s\n", opt_name, ipstr);
+        goto PRINT_HELP_AND_EXIT;
+    }
+
+    void *skaddr_ptr = is_listen_addr ? &g_listen_skaddr : &g_remote_skaddr;
+    if (ipfamily == AF_INET) {
+        build_sock_addr4(skaddr_ptr, ipstr, portno);
+    } else {
+        build_sock_addr6(skaddr_ptr, ipstr, portno);
+    }
+
+    if (is_listen_addr) {
+        strcpy(g_listen_ipstr, ipstr);
+        g_listen_portno = portno;
+    } else {
+        strcpy(g_remote_ipstr, ipstr);
+        g_remote_portno = portno;
+    }
+    return;
+
+PRINT_HELP_AND_EXIT:
+    print_command_help();
+    exit(1);
+}
+
+static void parse_command_args(int argc, char *argv[]) {
+    char opt_listen_addr[IP6STRLEN + PORTSTRLEN] = {0};
+    char opt_remote_addr[IP6STRLEN + PORTSTRLEN] = {0};
+
+    opterr = 0;
+    int shortopt = -1;
+    const char *optstr = "L:R:s:rafvVh";
+    while ((shortopt = getopt(argc, argv, optstr)) != -1) {
+        switch (shortopt) {
+            case 'L':
+                if (strlen(optarg) + 1 > IP4STRLEN + PORTSTRLEN) {
+                    printf("[parse_command_args] invalid listen addr: %s\n", optarg);
+                    goto PRINT_HELP_AND_EXIT;
+                }
+                strcpy(opt_listen_addr, optarg);
+                break;
+            case 'R':
+                if (strlen(optarg) + 1 > IP6STRLEN + PORTSTRLEN) {
+                    printf("[parse_command_args] invalid remote addr: %s\n", optarg);
+                    goto PRINT_HELP_AND_EXIT;
+                }
+                strcpy(opt_remote_addr, optarg);
+                break;
+            case 's':
+                g_syn_maxcnt = strtoul(optarg, NULL, 10);
+                if (g_syn_maxcnt == 0) {
+                    printf("[parse_command_args] invalid tcp syn cnt: %s\n", optarg);
+                    goto PRINT_HELP_AND_EXIT;
+                }
+                break;
+            case 'r':
+                g_options |= OPT_REUSE_PORT;
+                break;
+            case 'a':
+                g_options |= OPT_QUICK_ACK;
+                break;
+            case 'f':
+                g_options |= OPT_FAST_OPEN;
+                break;
+            case 'v':
+                g_verbose = true;
+                break;
+            case 'V':
+                printf(DNS2TCP_VER"\n");
+                exit(0);
+            case 'h':
+                print_command_help();
+                exit(0);
+            case '?':
+                if (!strchr(optstr, optopt)) {
+                    printf("[parse_command_args] unknown option '-%c'\n", optopt);
+                } else {
+                    printf("[parse_command_args] missing optval '-%c'\n", optopt);
+                }
+                goto PRINT_HELP_AND_EXIT;
+        }
+    }
+
+    if (strlen(opt_listen_addr) == 0) {
+        printf("[parse_command_args] missing option: '-L'\n");
+        goto PRINT_HELP_AND_EXIT;
+    }
+    if (strlen(opt_remote_addr) == 0) {
+        printf("[parse_command_args] missing option: '-R'\n");
+        goto PRINT_HELP_AND_EXIT;
+    }
+
+    parse_address_opt(opt_listen_addr, true);
+    parse_address_opt(opt_remote_addr, false);
+    return;
+
+PRINT_HELP_AND_EXIT:
+    print_command_help();
+    exit(1);
+}