add url link to pre-build binariesupstream

2 files changed, 210 insertions, 200 deletions

diff --git a/README.md b/README.md
index 7bdf493..da40afa 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,16 @@ Userspace GRE tunnel, designed for OpenVZ servers (require TUN device support).
 
 Checksum, Key, Sequence are not supported.
 
+## Pre-builds ##
+
+Platform  | Architecture | URL
+----------|--------------|----
+GNU/Linux | x86_64       | https://s3.pxx.io/snapshot/gre/gre-x86_64
+     | armv6l       | https://s3.pxx.io/snapshot/gre/gre-armv6l
+     | armv7l       | https://s3.pxx.io/snapshot/gre/gre-armv7l
+     | aarch64      | https://s3.pxx.io/snapshot/gre/gre-aarch64
+
+
 ## Build ##
 
 ```bash
@@ -18,7 +28,7 @@ sudo ./gre <tun dev> remote local
 
 ## License ##
 
-Copyright (C) 2015, Xiaoxiao <i@xiaoxiao.im>
+Copyright (C) 2015 - 2017, Xiaoxiao <i@pxx.io>
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
diff --git a/gre.c b/gre.c
index 22ac0f6..eaef4eb 100644
--- a/gre.c
+++ b/gre.c
@@ -1,7 +1,7 @@
 /*
  * gre.c - userspace GRE tunnel
  *
- * Copyright (C) 2015, Xiaoxiao <i@xiaoxiao.im>
+ * Copyright (C) 2015 - 2017, Xiaoxiao <i@pxx.io>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -50,231 +50,231 @@ static int daemonize(void);
 
 int main(int argc, char **argv)
 {
-	fd_set readset;
-
-	if (argc != 4)
-	{
-		printf("usage: %s <tun> remote local\n", argv[0]);
-		return EXIT_FAILURE;
-	}
-
-	tun = tun_new(argv[1]);
-	if (tun < 0)
-	{
-		printf("failed to init tun device\n");
-		return EXIT_FAILURE;
-	}
-
-	sock = socket(AF_INET, SOCK_RAW, IPPROTO_GRE);
-	if (sock < 0)
-	{
-		perror("socket");
-		return EXIT_FAILURE;
-	}
-
-	struct sockaddr_in local;
-	local.sin_family = AF_INET;
-	local.sin_port = htons(IPPROTO_GRE);
-	local.sin_addr.s_addr = inet_addr(argv[3]);
-	if (local.sin_addr.s_addr == INADDR_NONE)
-	{
-		fprintf(stderr, "bad local address\n");
-		return EXIT_FAILURE;
-	}
-	else
-	{
-		if (bind(sock, (struct sockaddr *)&local, sizeof(local)) != 0)
-		{
-			perror("bind");
-			return EXIT_FAILURE;
-		}
-	}
-
-	remote.sin_family = AF_INET;
-	remote.sin_port = htons(IPPROTO_GRE);
-	remote.sin_addr.s_addr = inet_addr(argv[2]);
-	if (remote.sin_addr.s_addr == INADDR_NONE)
-	{
-		fprintf(stderr, "bad remote address\n");
-		return EXIT_FAILURE;
-	}
-
-	setnonblock(sock);
-	setnonblock(tun);
-	runas("nobody");
-	daemonize();
-
-	int maxfd = (tun > sock ? tun : sock) + 1;
-	while (1)
-	{
-		FD_ZERO(&readset);
-		FD_SET(tun, &readset);
-		FD_SET(sock, &readset);
-
-		int r = select(maxfd, &readset, NULL, NULL, NULL);
-		if (r < 0)
-		{
-			if (errno == EINTR)
-			{
-				continue;
-			}
-			else
-			{
-				perror("select");
-				break;
-			}
-		}
-
-		if (FD_ISSET(sock, &readset))
-		{
-			gre_cb();
-		}
-
-		if (FD_ISSET(tun, &readset))
-		{
-			tun_cb();
-		}
-	}
-
-	return 0;
+    fd_set readset;
+
+    if (argc != 4)
+    {
+        printf("usage: %s <tun> remote local\n", argv[0]);
+        return EXIT_FAILURE;
+    }
+
+    tun = tun_new(argv[1]);
+    if (tun < 0)
+    {
+        printf("failed to init tun device\n");
+        return EXIT_FAILURE;
+    }
+
+    sock = socket(AF_INET, SOCK_RAW, IPPROTO_GRE);
+    if (sock < 0)
+    {
+        perror("socket");
+        return EXIT_FAILURE;
+    }
+
+    struct sockaddr_in local;
+    local.sin_family = AF_INET;
+    local.sin_port = htons(IPPROTO_GRE);
+    local.sin_addr.s_addr = inet_addr(argv[3]);
+    if (local.sin_addr.s_addr == INADDR_NONE)
+    {
+        fprintf(stderr, "bad local address\n");
+        return EXIT_FAILURE;
+    }
+    else
+    {
+        if (bind(sock, (struct sockaddr *)&local, sizeof(local)) != 0)
+        {
+            perror("bind");
+            return EXIT_FAILURE;
+        }
+    }
+
+    remote.sin_family = AF_INET;
+    remote.sin_port = htons(IPPROTO_GRE);
+    remote.sin_addr.s_addr = inet_addr(argv[2]);
+    if (remote.sin_addr.s_addr == INADDR_NONE)
+    {
+        fprintf(stderr, "bad remote address\n");
+        return EXIT_FAILURE;
+    }
+
+    setnonblock(sock);
+    setnonblock(tun);
+    runas("nobody");
+    daemonize();
+
+    int maxfd = (tun > sock ? tun : sock) + 1;
+    while (1)
+    {
+        FD_ZERO(&readset);
+        FD_SET(tun, &readset);
+        FD_SET(sock, &readset);
+
+        int r = select(maxfd, &readset, NULL, NULL, NULL);
+        if (r < 0)
+        {
+            if (errno == EINTR)
+            {
+                continue;
+            }
+            else
+            {
+                perror("select");
+                break;
+            }
+        }
+
+        if (FD_ISSET(sock, &readset))
+        {
+            gre_cb();
+        }
+
+        if (FD_ISSET(tun, &readset))
+        {
+            tun_cb();
+        }
+    }
+
+    return 0;
 }
 
 static void gre_cb(void)
 {
-	int ihl;	// IP header length
-	int n;
-
-	n = recv(sock, buf, sizeof(buf), 0);
-	if (n < 0)
-	{
-		perror("recv");
-		return;
-	}
-	ihl = 4 * (buf[0] & 0x0f);
-	if (ihl > 60 || ihl < 20)
-	{
-		printf("IPv4 header too long\n");
-		return;
-	}
-	// check source IPv4 address
-	if (*(uint32_t *)(buf + 12) != remote.sin_addr.s_addr)
-	{
-		return;
-	}
-
-	// parse GRE header
-	if (*(uint16_t *)(buf + ihl) != 0)
-	{
-		return;
-	}
-	uint16_t protocol = ntohs(*(uint16_t *)(buf + ihl + 2));
-	if (protocol != 0x0800)
-	{
-		return;
-	}
-
-	write(tun, buf + ihl + 4, n - ihl - 4);
+    int ihl;    // IP header length
+    int n;
+
+    n = recv(sock, buf, sizeof(buf), 0);
+    if (n < 0)
+    {
+        perror("recv");
+        return;
+    }
+    ihl = 4 * (buf[0] & 0x0f);
+    if (ihl > 60 || ihl < 20)
+    {
+        printf("IPv4 header too long\n");
+        return;
+    }
+    // check source IPv4 address
+    if (*(uint32_t *)(buf + 12) != remote.sin_addr.s_addr)
+    {
+        return;
+    }
+
+    // parse GRE header
+    if (*(uint16_t *)(buf + ihl) != 0)
+    {
+        return;
+    }
+    uint16_t protocol = ntohs(*(uint16_t *)(buf + ihl + 2));
+    if (protocol != 0x0800)
+    {
+        return;
+    }
+
+    write(tun, buf + ihl + 4, n - ihl - 4);
 }
 
 static void tun_cb(void)
 {
-	int n;
-
-	n = read(tun, buf + 4, sizeof(buf) - 4);
-	if (n < 0)
-	{
-		perror("read");
-		return;
-	}
-	*(uint16_t *)(buf) = 0;
-	*(uint16_t *)(buf + 2) = htons(0x0800);
-	sendto(sock, buf, n + 4, 0, (struct sockaddr *)&remote, sizeof(struct sockaddr));
+    int n;
+
+    n = read(tun, buf + 4, sizeof(buf) - 4);
+    if (n < 0)
+    {
+        perror("read");
+        return;
+    }
+    *(uint16_t *)(buf) = 0;
+    *(uint16_t *)(buf + 2) = htons(0x0800);
+    sendto(sock, buf, n + 4, 0, (struct sockaddr *)&remote, sizeof(struct sockaddr));
 }
 
 static int tun_new(const char *dev)
 {
-	struct ifreq ifr;
-	int fd, err;
-
-	fd = open("/dev/net/tun", O_RDWR);
-	if (fd < 0)
-	{
-		return -1;
-	}
-
-	bzero(&ifr, sizeof(struct ifreq));
-
-	ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
-	if (*dev != '\0')
-	{
-		strncpy(ifr.ifr_name, dev, IFNAMSIZ);
-	}
-
-	err = ioctl(fd, TUNSETIFF, (void *)&ifr);
-	if (err < 0)
-	{
-		return err;
-	}
-	return fd;
+    struct ifreq ifr;
+    int fd, err;
+
+    fd = open("/dev/net/tun", O_RDWR);
+    if (fd < 0)
+    {
+        return -1;
+    }
+
+    bzero(&ifr, sizeof(struct ifreq));
+
+    ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+    if (*dev != '\0')
+    {
+        strncpy(ifr.ifr_name, dev, IFNAMSIZ);
+    }
+
+    err = ioctl(fd, TUNSETIFF, (void *)&ifr);
+    if (err < 0)
+    {
+        return err;
+    }
+    return fd;
 }
 
 static int setnonblock(int fd)
 {
-	int flags;
-	flags = fcntl(fd, F_GETFL, 0);
-	if (flags == -1)
-	{
-		return -1;
-	}
-	if (-1 == fcntl(fd, F_SETFL, flags | O_NONBLOCK))
-	{
-		return -1;
-	}
-	return 0;
+    int flags;
+    flags = fcntl(fd, F_GETFL, 0);
+    if (flags == -1)
+    {
+        return -1;
+    }
+    if (-1 == fcntl(fd, F_SETFL, flags | O_NONBLOCK))
+    {
+        return -1;
+    }
+    return 0;
 }
 
 static int runas(const char *user)
 {
-	struct passwd *pw_ent = getpwnam(user);
-
-	if (pw_ent != NULL)
-	{
-		if (setegid(pw_ent->pw_gid) != 0)
-		{
-			return -1;
-		}
-		if (seteuid(pw_ent->pw_uid) != 0)
-		{
-			return -1;
-		}
-	}
-
-	return 0;
+    struct passwd *pw_ent = getpwnam(user);
+
+    if (pw_ent != NULL)
+    {
+        if (setegid(pw_ent->pw_gid) != 0)
+        {
+            return -1;
+        }
+        if (seteuid(pw_ent->pw_uid) != 0)
+        {
+            return -1;
+        }
+    }
+
+    return 0;
 }
 
 static int daemonize(void)
 {
-	pid_t pid;
+    pid_t pid;
 
-	pid = fork();
-	if (pid < 0)
-	{
-		perror("fork");
-		return -1;
-	}
+    pid = fork();
+    if (pid < 0)
+    {
+        perror("fork");
+        return -1;
+    }
 
-	if (pid > 0)
-	{
-		exit(0);
-	}
+    if (pid > 0)
+    {
+        exit(0);
+    }
 
-	umask(0);
+    umask(0);
 
-	if (setsid() < 0)
-	{
-		perror("setsid");
-		return -1;
-	}
+    if (setsid() < 0)
+    {
+        perror("setsid");
+        return -1;
+    }
 
-	return 0;
+    return 0;
 }