🌴 Sync 2026-03-05 23:51:42

shadowsocksr-libev/src/server/netutils.c

@@ -0,0 +1,297 @@
+/*
+ * netutils.c - Network utilities
+ *
+ * Copyright (C) 2013 - 2016, Max Lv <max.c.lv@gmail.com>
+ *
+ * This file is part of the shadowsocks-libev.
+ *
+ * shadowsocks-libev is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * shadowsocks-libev is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with shadowsocks-libev; see the file COPYING. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include <math.h>
+
+#include <libcork/core.h>
+#include <udns.h>
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#ifdef __MINGW32__
+#include "win32.h"
+#define sleep(n) Sleep(1000 * (n))
+#else
+#include <sys/socket.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#endif
+
+#if defined(HAVE_SYS_IOCTL_H) && defined(HAVE_NET_IF_H) && defined(__linux__)
+#include <net/if.h>
+#include <sys/ioctl.h>
+#define SET_INTERFACE
+#endif
+
+#include "netutils.h"
+#include "utils.h"
+
+#ifndef SO_REUSEPORT
+#define SO_REUSEPORT 15
+#endif
+
+extern int verbose;
+
+static const char valid_label_bytes[] =
+    "-0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz";
+
+#if defined(MODULE_LOCAL)
+extern int keep_resolving;
+#endif
+
+int
+set_reuseport(int socket)
+{
+    int opt = 1;
+    return setsockopt(socket, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt));
+}
+
+size_t
+get_sockaddr_len(struct sockaddr *addr)
+{
+    if (addr->sa_family == AF_INET) {
+        return sizeof(struct sockaddr_in);
+    } else if (addr->sa_family == AF_INET6) {
+        return sizeof(struct sockaddr_in6);
+    }
+    return 0;
+}
+
+#ifdef SET_INTERFACE
+int
+setinterface(int socket_fd, const char *interface_name)
+{
+    struct ifreq interface;
+    memset(&interface, 0, sizeof(struct ifreq));
+    strncpy(interface.ifr_name, interface_name, IFNAMSIZ);
+    int res = setsockopt(socket_fd, SOL_SOCKET, SO_BINDTODEVICE, &interface,
+                         sizeof(struct ifreq));
+    return res;
+}
+
+#endif
+
+int
+bind_to_address(int socket_fd, const char *host)
+{
+    if (host != NULL) {
+        struct cork_ip ip;
+        struct sockaddr_storage storage;
+        memset(&storage, 0, sizeof(struct sockaddr_storage));
+        if (cork_ip_init(&ip, host) != -1) {
+            if (ip.version == 4) {
+                struct sockaddr_in *addr = (struct sockaddr_in *)&storage;
+                dns_pton(AF_INET, host, &addr->sin_addr);
+                addr->sin_family = AF_INET;
+                return bind(socket_fd, (struct sockaddr *)addr, sizeof(struct sockaddr_in));
+            } else if (ip.version == 6) {
+                struct sockaddr_in6 *addr = (struct sockaddr_in6 *)&storage;
+                dns_pton(AF_INET6, host, &addr->sin6_addr);
+                addr->sin6_family = AF_INET6;
+                return bind(socket_fd, (struct sockaddr *)addr, sizeof(struct sockaddr_in6));
+            }
+        }
+    }
+    return -1;
+}
+
+ssize_t
+get_sockaddr(char *host, char *port,
+             struct sockaddr_storage *storage, int block,
+             int ipv6first)
+{
+    struct cork_ip ip;
+    if (cork_ip_init(&ip, host) != -1) {
+        if (ip.version == 4) {
+            struct sockaddr_in *addr = (struct sockaddr_in *)storage;
+            addr->sin_family = AF_INET;
+            dns_pton(AF_INET, host, &(addr->sin_addr));
+            if (port != NULL) {
+                addr->sin_port = htons(atoi(port));
+            }
+        } else if (ip.version == 6) {
+            struct sockaddr_in6 *addr = (struct sockaddr_in6 *)storage;
+            addr->sin6_family = AF_INET6;
+            dns_pton(AF_INET6, host, &(addr->sin6_addr));
+            if (port != NULL) {
+                addr->sin6_port = htons(atoi(port));
+            }
+        }
+        return 0;
+    } else {
+        struct addrinfo hints;
+        struct addrinfo *result, *rp;
+
+        memset(&hints, 0, sizeof(struct addrinfo));
+        hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */
+        hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */
+
+        int err, i;
+
+        for (i = 1; i < 8; i++) {
+            err = getaddrinfo(host, port, &hints, &result);
+#if defined(MODULE_LOCAL)
+            if (!keep_resolving)
+                break;
+#endif
+            if ((!block || !err)) {
+                break;
+            } else {
+                sleep(pow(2, i));
+                LOGE("failed to resolve server name, wait %.0f seconds", pow(2, i));
+            }
+        }
+
+        if (err != 0) {
+            LOGE("getaddrinfo: %s", gai_strerror(err));
+            return -1;
+        }
+
+        int prefer_af = ipv6first ? AF_INET6 : AF_INET;
+        for (rp = result; rp != NULL; rp = rp->ai_next)
+            if (rp->ai_family == prefer_af) {
+                if (rp->ai_family == AF_INET)
+                    memcpy(storage, rp->ai_addr, sizeof(struct sockaddr_in));
+                else if (rp->ai_family == AF_INET6)
+                    memcpy(storage, rp->ai_addr, sizeof(struct sockaddr_in6));
+                break;
+            }
+
+        if (rp == NULL) {
+            for (rp = result; rp != NULL; rp = rp->ai_next) {
+                if (rp->ai_family == AF_INET)
+                    memcpy(storage, rp->ai_addr, sizeof(struct sockaddr_in));
+                else if (rp->ai_family == AF_INET6)
+                    memcpy(storage, rp->ai_addr, sizeof(struct sockaddr_in6));
+                break;
+            }
+        }
+
+        if (rp == NULL) {
+            LOGE("failed to resolve remote addr");
+            return -1;
+        }
+
+        freeaddrinfo(result);
+        return 0;
+    }
+
+    return -1;
+}
+
+int
+sockaddr_cmp(struct sockaddr_storage *addr1,
+             struct sockaddr_storage *addr2, socklen_t len)
+{
+    struct sockaddr_in *p1_in   = (struct sockaddr_in *)addr1;
+    struct sockaddr_in *p2_in   = (struct sockaddr_in *)addr2;
+    struct sockaddr_in6 *p1_in6 = (struct sockaddr_in6 *)addr1;
+    struct sockaddr_in6 *p2_in6 = (struct sockaddr_in6 *)addr2;
+    if (p1_in->sin_family < p2_in->sin_family)
+        return -1;
+    if (p1_in->sin_family > p2_in->sin_family)
+        return 1;
+    /* compare ip4 */
+    if (p1_in->sin_family == AF_INET) {
+        /* just order it, ntohs not required */
+        if (p1_in->sin_port < p2_in->sin_port)
+            return -1;
+        if (p1_in->sin_port > p2_in->sin_port)
+            return 1;
+        return memcmp(&p1_in->sin_addr, &p2_in->sin_addr, INET_SIZE);
+    } else if (p1_in6->sin6_family == AF_INET6) {
+        /* just order it, ntohs not required */
+        if (p1_in6->sin6_port < p2_in6->sin6_port)
+            return -1;
+        if (p1_in6->sin6_port > p2_in6->sin6_port)
+            return 1;
+        return memcmp(&p1_in6->sin6_addr, &p2_in6->sin6_addr,
+                      INET6_SIZE);
+    } else {
+        /* eek unknown type, perform this comparison for sanity. */
+        return memcmp(addr1, addr2, len);
+    }
+}
+
+int
+sockaddr_cmp_addr(struct sockaddr_storage *addr1,
+                  struct sockaddr_storage *addr2, socklen_t len)
+{
+    struct sockaddr_in *p1_in   = (struct sockaddr_in *)addr1;
+    struct sockaddr_in *p2_in   = (struct sockaddr_in *)addr2;
+    struct sockaddr_in6 *p1_in6 = (struct sockaddr_in6 *)addr1;
+    struct sockaddr_in6 *p2_in6 = (struct sockaddr_in6 *)addr2;
+    if (p1_in->sin_family < p2_in->sin_family)
+        return -1;
+    if (p1_in->sin_family > p2_in->sin_family)
+        return 1;
+    /* compare ip4 */
+    if (p1_in->sin_family == AF_INET) {
+        return memcmp(&p1_in->sin_addr, &p2_in->sin_addr, INET_SIZE);
+    } else if (p1_in6->sin6_family == AF_INET6) {
+        return memcmp(&p1_in6->sin6_addr, &p2_in6->sin6_addr,
+                      INET6_SIZE);
+    } else {
+        /* eek unknown type, perform this comparison for sanity. */
+        return memcmp(addr1, addr2, len);
+    }
+}
+
+int
+validate_hostname(const char *hostname, const int hostname_len)
+{
+    if (hostname == NULL)
+        return 0;
+
+    if (hostname_len < 1 || hostname_len > 255)
+        return 0;
+
+    if (hostname[0] == '.')
+        return 0;
+
+    const char *label = hostname;
+    while (label < hostname + hostname_len) {
+        size_t label_len = hostname_len - (label - hostname);
+        char *next_dot   = strchr(label, '.');
+        if (next_dot != NULL)
+            label_len = next_dot - label;
+
+        if (label + label_len > hostname + hostname_len)
+            return 0;
+
+        if (label_len > 63 || label_len < 1)
+            return 0;
+
+        if (label[0] == '-' || label[label_len - 1] == '-')
+            return 0;
+
+        if (strspn(label, valid_label_bytes) < label_len)
+            return 0;
+
+        label += label_len + 1;
+    }
+
+    return 1;
+}