Merge branch 'debian/experimental-2.5'

1 files changed, 1246 insertions, 0 deletions

diff --git a/src/openvpn/networking_sitnl.c b/src/openvpn/networking_sitnl.c
new file mode 100644
index 0000000..713a213
--- /dev/null
+++ b/src/openvpn/networking_sitnl.c
@@ -0,0 +1,1246 @@
+/*
+ *  Simplified Interface To NetLink
+ *
+ *  Copyright (C) 2016-2018 Antonio Quartulli <a@unstable.cc>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program 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 this program (see the file COPYING included with this
+ *  distribution); if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#elif defined(_MSC_VER)
+#include "config-msvc.h"
+#endif
+
+#ifdef TARGET_LINUX
+
+#include "syshead.h"
+
+#include "errlevel.h"
+#include "buffer.h"
+#include "networking.h"
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#define SNDBUF_SIZE (1024 * 2)
+#define RCVBUF_SIZE (1024 * 4)
+
+#define SITNL_ADDATTR(_msg, _max_size, _attr, _data, _size)         \
+    {                                                               \
+        if (sitnl_addattr(_msg, _max_size, _attr, _data, _size) < 0) \
+        {                                                           \
+            goto err;                                               \
+        }                                                           \
+    }
+
+#define NLMSG_TAIL(nmsg) \
+    ((struct rtattr *)(((uint8_t *)(nmsg)) + NLMSG_ALIGN((nmsg)->nlmsg_len)))
+
+/**
+ * Generic address data structure used to pass addresses and prefixes as
+ * argument to AF family agnostic functions
+ */
+typedef union {
+    in_addr_t ipv4;
+    struct in6_addr ipv6;
+} inet_address_t;
+
+/**
+ * Link state request message
+ */
+struct sitnl_link_req {
+    struct nlmsghdr n;
+    struct ifinfomsg i;
+    char buf[256];
+};
+
+/**
+ * Address request message
+ */
+struct sitnl_addr_req {
+    struct nlmsghdr n;
+    struct ifaddrmsg i;
+    char buf[256];
+};
+
+/**
+ * Route request message
+ */
+struct sitnl_route_req {
+    struct nlmsghdr n;
+    struct rtmsg r;
+    char buf[256];
+};
+
+typedef int (*sitnl_parse_reply_cb)(struct nlmsghdr *msg, void *arg);
+
+/**
+ * Object returned by route request operation
+ */
+struct sitnl_route_data_cb {
+    unsigned int iface;
+    inet_address_t gw;
+};
+
+/**
+ * Helper function used to easily add attributes to a rtnl message
+ */
+static int
+sitnl_addattr(struct nlmsghdr *n, int maxlen, int type, const void *data,
+              int alen)
+{
+    int len = RTA_LENGTH(alen);
+    struct rtattr *rta;
+
+    if ((int)(NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len)) > maxlen)
+    {
+        msg(M_WARN, "%s: rtnl: message exceeded bound of %d", __func__,
+            maxlen);
+        return -EMSGSIZE;
+    }
+
+    rta = NLMSG_TAIL(n);
+    rta->rta_type = type;
+    rta->rta_len = len;
+
+    if (!data)
+    {
+        memset(RTA_DATA(rta), 0, alen);
+    }
+    else
+    {
+        memcpy(RTA_DATA(rta), data, alen);
+    }
+
+    n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
+
+    return 0;
+}
+
+/**
+ * Open RTNL socket
+ */
+static int
+sitnl_socket(void)
+{
+    int sndbuf = SNDBUF_SIZE;
+    int rcvbuf = RCVBUF_SIZE;
+    int fd;
+
+    fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+    if (fd < 0)
+    {
+        msg(M_WARN, "%s: cannot open netlink socket", __func__);
+        return fd;
+    }
+
+    if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf)) < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: SO_SNDBUF", __func__);
+        close(fd);
+        return -1;
+    }
+
+    if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, sizeof(rcvbuf)) < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: SO_RCVBUF", __func__);
+        close(fd);
+        return -1;
+    }
+
+    return fd;
+}
+
+/**
+ * Bind socket to Netlink subsystem
+ */
+static int
+sitnl_bind(int fd, uint32_t groups)
+{
+    socklen_t addr_len;
+    struct sockaddr_nl local;
+
+    CLEAR(local);
+
+    local.nl_family = AF_NETLINK;
+    local.nl_groups = groups;
+
+    if (bind(fd, (struct sockaddr *)&local, sizeof(local)) < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: cannot bind netlink socket", __func__);
+        return -errno;
+    }
+
+    addr_len = sizeof(local);
+    if (getsockname(fd, (struct sockaddr *)&local, &addr_len) < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: cannot getsockname", __func__);
+        return -errno;
+    }
+
+    if (addr_len != sizeof(local))
+    {
+        msg(M_WARN, "%s: wrong address length %d", __func__, addr_len);
+        return -EINVAL;
+    }
+
+    if (local.nl_family != AF_NETLINK)
+    {
+        msg(M_WARN, "%s: wrong address family %d", __func__, local.nl_family);
+        return -EINVAL;
+    }
+
+    return 0;
+}
+
+/**
+ * Send Netlink message and run callback on reply (if specified)
+ */
+static int
+sitnl_send(struct nlmsghdr *payload, pid_t peer, unsigned int groups,
+           sitnl_parse_reply_cb cb, void *arg_cb)
+{
+    int len, rem_len, fd, ret, rcv_len;
+    struct sockaddr_nl nladdr;
+    struct nlmsgerr *err;
+    struct nlmsghdr *h;
+    unsigned int seq;
+    char buf[1024 * 16];
+    struct iovec iov =
+    {
+        .iov_base = payload,
+        .iov_len = payload->nlmsg_len,
+    };
+    struct msghdr nlmsg =
+    {
+        .msg_name = &nladdr,
+        .msg_namelen = sizeof(nladdr),
+        .msg_iov = &iov,
+        .msg_iovlen = 1,
+    };
+
+    CLEAR(nladdr);
+
+    nladdr.nl_family = AF_NETLINK;
+    nladdr.nl_pid = peer;
+    nladdr.nl_groups = groups;
+
+    payload->nlmsg_seq = seq = time(NULL);
+
+    /* no need to send reply */
+    if (!cb)
+    {
+        payload->nlmsg_flags |= NLM_F_ACK;
+    }
+
+    fd = sitnl_socket();
+    if (fd < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: can't open rtnl socket", __func__);
+        return -errno;
+    }
+
+    ret = sitnl_bind(fd, 0);
+    if (ret < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: can't bind rtnl socket", __func__);
+        ret = -errno;
+        goto out;
+    }
+
+    ret = sendmsg(fd, &nlmsg, 0);
+    if (ret < 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: rtnl: error on sendmsg()", __func__);
+        ret = -errno;
+        goto out;
+    }
+
+    /* prepare buffer to store RTNL replies */
+    memset(buf, 0, sizeof(buf));
+    iov.iov_base = buf;
+
+    while (1)
+    {
+        /*
+         * iov_len is modified by recvmsg(), therefore has to be initialized before
+         * using it again
+         */
+        msg(D_RTNL, "%s: checking for received messages", __func__);
+        iov.iov_len = sizeof(buf);
+        rcv_len = recvmsg(fd, &nlmsg, 0);
+        msg(D_RTNL, "%s: rtnl: received %d bytes", __func__, rcv_len);
+        if (rcv_len < 0)
+        {
+            if ((errno == EINTR) || (errno == EAGAIN))
+            {
+                msg(D_RTNL, "%s: interrupted call", __func__);
+                continue;
+            }
+            msg(M_WARN | M_ERRNO, "%s: rtnl: error on recvmsg()", __func__);
+            ret = -errno;
+            goto out;
+        }
+
+        if (rcv_len == 0)
+        {
+            msg(M_WARN, "%s: rtnl: socket reached unexpected EOF", __func__);
+            ret = -EIO;
+            goto out;
+        }
+
+        if (nlmsg.msg_namelen != sizeof(nladdr))
+        {
+            msg(M_WARN, "%s: sender address length: %u (expected %zu)",
+                __func__, nlmsg.msg_namelen, sizeof(nladdr));
+            ret = -EIO;
+            goto out;
+        }
+
+        h = (struct nlmsghdr *)buf;
+        while (rcv_len >= (int)sizeof(*h))
+        {
+            len = h->nlmsg_len;
+            rem_len = len - sizeof(*h);
+
+            if ((rem_len < 0) || (len > rcv_len))
+            {
+                if (nlmsg.msg_flags & MSG_TRUNC)
+                {
+                    msg(M_WARN, "%s: truncated message", __func__);
+                    ret = -EIO;
+                    goto out;
+                }
+                msg(M_WARN, "%s: malformed message: len=%d", __func__, len);
+                ret = -EIO;
+                goto out;
+            }
+
+/*            if (((int)nladdr.nl_pid != peer) || (h->nlmsg_pid != nladdr.nl_pid)
+ *               || (h->nlmsg_seq != seq))
+ *           {
+ *               rcv_len -= NLMSG_ALIGN(len);
+ *               h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
+ *               msg(M_DEBUG, "%s: skipping unrelated message. nl_pid:%d (peer:%d) nl_msg_pid:%d nl_seq:%d seq:%d",
+ *                   __func__, (int)nladdr.nl_pid, peer, h->nlmsg_pid,
+ *                   h->nlmsg_seq, seq);
+ *               continue;
+ *           }
+ */
+            if (h->nlmsg_type == NLMSG_ERROR)
+            {
+                err = (struct nlmsgerr *)NLMSG_DATA(h);
+                if (rem_len < (int)sizeof(struct nlmsgerr))
+                {
+                    msg(M_WARN, "%s: ERROR truncated", __func__);
+                    ret = -EIO;
+                }
+                else
+                {
+                    if (!err->error)
+                    {
+                        ret = 0;
+                        if (cb)
+                        {
+                            ret = cb(h, arg_cb);
+                        }
+                    }
+                    else
+                    {
+                        msg(M_WARN, "%s: rtnl: generic error (%d): %s",
+                            __func__, err->error, strerror(-err->error));
+                        ret = err->error;
+                    }
+                }
+                goto out;
+            }
+
+            if (cb)
+            {
+                ret = cb(h, arg_cb);
+                goto out;
+            }
+            else
+            {
+                msg(M_WARN, "%s: RTNL: unexpected reply", __func__);
+            }
+
+            rcv_len -= NLMSG_ALIGN(len);
+            h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
+        }
+
+        if (nlmsg.msg_flags & MSG_TRUNC)
+        {
+            msg(M_WARN, "%s: message truncated", __func__);
+            continue;
+        }
+
+        if (rcv_len)
+        {
+            msg(M_WARN, "%s: rtnl: %d not parsed bytes", __func__, rcv_len);
+            ret = -1;
+            goto out;
+        }
+    }
+out:
+    close(fd);
+
+    return ret;
+}
+
+typedef struct {
+    int addr_size;
+    inet_address_t gw;
+    char iface[IFNAMSIZ];
+} route_res_t;
+
+static int
+sitnl_route_save(struct nlmsghdr *n, void *arg)
+{
+    route_res_t *res = arg;
+    struct rtmsg *r = NLMSG_DATA(n);
+    struct rtattr *rta = RTM_RTA(r);
+    int len = n->nlmsg_len - NLMSG_LENGTH(sizeof(*r));
+    unsigned int ifindex = 0;
+
+    while (RTA_OK(rta, len))
+    {
+        switch (rta->rta_type)
+        {
+            /* route interface */
+            case RTA_OIF:
+                ifindex = *(unsigned int *)RTA_DATA(rta);
+                break;
+
+            /* route prefix */
+            case RTA_DST:
+                break;
+
+            /* GW for the route */
+            case RTA_GATEWAY:
+                memcpy(&res->gw, RTA_DATA(rta), res->addr_size);
+                break;
+        }
+
+        rta = RTA_NEXT(rta, len);
+    }
+
+    if (!if_indextoname(ifindex, res->iface))
+    {
+        msg(M_WARN | M_ERRNO, "%s: rtnl: can't get ifname for index %d",
+            __func__, ifindex);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int
+sitnl_route_best_gw(sa_family_t af_family, const inet_address_t *dst,
+                    void *best_gw, char *best_iface)
+{
+    struct sitnl_route_req req;
+    route_res_t res;
+    int ret = -EINVAL;
+
+    ASSERT(best_gw);
+    ASSERT(best_iface);
+
+    CLEAR(req);
+    CLEAR(res);
+
+    req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.r));
+    req.n.nlmsg_type = RTM_GETROUTE;
+    req.n.nlmsg_flags = NLM_F_REQUEST;
+
+    req.r.rtm_family = af_family;
+
+    switch (af_family)
+    {
+        case AF_INET:
+            res.addr_size = sizeof(in_addr_t);
+            req.n.nlmsg_flags |= NLM_F_DUMP;
+            break;
+
+        case AF_INET6:
+            res.addr_size = sizeof(struct in6_addr);
+            break;
+
+        default:
+            /* unsupported */
+            return -EINVAL;
+    }
+
+    SITNL_ADDATTR(&req.n, sizeof(req), RTA_DST, dst, res.addr_size);
+
+    ret = sitnl_send(&req.n, 0, 0, sitnl_route_save, &res);
+    if (ret < 0)
+    {
+        goto err;
+    }
+
+    /* save result in output variables */
+    memcpy(best_gw, &res.gw, res.addr_size);
+    strncpy(best_iface, res.iface, IFNAMSIZ);
+err:
+    return ret;
+
+}
+
+/* used by iproute2 implementation too */
+int
+net_route_v6_best_gw(openvpn_net_ctx_t *ctx, const struct in6_addr *dst,
+                     struct in6_addr *best_gw, char *best_iface)
+{
+    inet_address_t dst_v6 = {0};
+    char buf[INET6_ADDRSTRLEN];
+    int ret;
+
+    if (dst)
+    {
+        dst_v6.ipv6 = *dst;
+    }
+
+    msg(D_ROUTE, "%s query: dst %s", __func__,
+        inet_ntop(AF_INET6, &dst_v6.ipv6, buf, sizeof(buf)));
+
+    ret = sitnl_route_best_gw(AF_INET6, &dst_v6, best_gw, best_iface);
+    if (ret < 0)
+    {
+        return ret;
+    }
+
+    msg(D_ROUTE, "%s result: via %s dev %s", __func__,
+        inet_ntop(AF_INET6, best_gw, buf, sizeof(buf)), best_iface);
+
+    return ret;
+
+}
+
+#ifdef ENABLE_SITNL
+
+int
+net_ctx_init(struct context *c, openvpn_net_ctx_t *ctx)
+{
+    (void)c;
+    (void)ctx;
+
+    return 0;
+}
+
+void
+net_ctx_reset(openvpn_net_ctx_t *ctx)
+{
+    (void)ctx;
+}
+
+void
+net_ctx_free(openvpn_net_ctx_t *ctx)
+{
+    (void)ctx;
+}
+
+int
+net_route_v4_best_gw(openvpn_net_ctx_t *ctx, const in_addr_t *dst,
+                     in_addr_t *best_gw, char *best_iface)
+{
+    inet_address_t dst_v4 = {0};
+    char buf[INET_ADDRSTRLEN];
+    int ret;
+
+    if (dst)
+    {
+        dst_v4.ipv4 = htonl(*dst);
+    }
+
+    msg(D_ROUTE, "%s query: dst %s", __func__,
+        inet_ntop(AF_INET, &dst_v4.ipv4, buf, sizeof(buf)));
+
+    ret = sitnl_route_best_gw(AF_INET, &dst_v4, best_gw, best_iface);
+    if (ret < 0)
+    {
+        return ret;
+    }
+
+    msg(D_ROUTE, "%s result: via %s dev %s", __func__,
+        inet_ntop(AF_INET, best_gw, buf, sizeof(buf)), best_iface);
+
+    /* result is expected in Host Order */
+    *best_gw = ntohl(*best_gw);
+
+    return ret;
+}
+
+int
+net_iface_up(openvpn_net_ctx_t *ctx, const char *iface, bool up)
+{
+    struct sitnl_link_req req;
+    int ifindex;
+
+    CLEAR(req);
+
+    if (!iface)
+    {
+        msg(M_WARN, "%s: passed NULL interface", __func__);
+        return -EINVAL;
+    }
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN, "%s: rtnl: cannot get ifindex for %s: %s", __func__, iface,
+            strerror(errno));
+        return -ENOENT;
+    }
+
+    req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i));
+    req.n.nlmsg_flags = NLM_F_REQUEST;
+    req.n.nlmsg_type = RTM_NEWLINK;
+
+    req.i.ifi_family = AF_PACKET;
+    req.i.ifi_index = ifindex;
+    req.i.ifi_change |= IFF_UP;
+    if (up)
+    {
+        req.i.ifi_flags |= IFF_UP;
+    }
+    else
+    {
+        req.i.ifi_flags &= ~IFF_UP;
+    }
+
+    msg(M_INFO, "%s: set %s %s", __func__, iface, up ? "up" : "down");
+
+    return sitnl_send(&req.n, 0, 0, NULL, NULL);
+}
+
+int
+net_iface_mtu_set(openvpn_net_ctx_t *ctx, const char *iface,
+                  uint32_t mtu)
+{
+    struct sitnl_link_req req;
+    int ifindex, ret = -1;
+
+    CLEAR(req);
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: rtnl: cannot get ifindex for %s", __func__,
+            iface);
+        return -1;
+    }
+
+    req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i));
+    req.n.nlmsg_flags = NLM_F_REQUEST;
+    req.n.nlmsg_type = RTM_NEWLINK;
+
+    req.i.ifi_family = AF_PACKET;
+    req.i.ifi_index = ifindex;
+
+    SITNL_ADDATTR(&req.n, sizeof(req), IFLA_MTU, &mtu, 4);
+
+    msg(M_INFO, "%s: mtu %u for %s", __func__, mtu, iface);
+
+    ret = sitnl_send(&req.n, 0, 0, NULL, NULL);
+err:
+    return ret;
+}
+
+static int
+sitnl_addr_set(int cmd, uint32_t flags, int ifindex, sa_family_t af_family,
+               const inet_address_t *local, const inet_address_t *remote,
+               int prefixlen)
+{
+    struct sitnl_addr_req req;
+    uint32_t size;
+    int ret = -EINVAL;
+
+    CLEAR(req);
+
+    req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i));
+    req.n.nlmsg_type = cmd;
+    req.n.nlmsg_flags = NLM_F_REQUEST | flags;
+
+    req.i.ifa_index = ifindex;
+    req.i.ifa_family = af_family;
+
+    switch (af_family)
+    {
+        case AF_INET:
+            size = sizeof(struct in_addr);
+            break;
+
+        case AF_INET6:
+            size = sizeof(struct in6_addr);
+            break;
+
+        default:
+            msg(M_WARN, "%s: rtnl: unknown address family %d", __func__,
+                af_family);
+            return -EINVAL;
+    }
+
+    /* if no prefixlen has been specified, assume host address */
+    if (prefixlen == 0)
+    {
+        prefixlen = size * 8;
+    }
+    req.i.ifa_prefixlen = prefixlen;
+
+    if (remote)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), IFA_ADDRESS, remote, size);
+    }
+
+    if (local)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), IFA_LOCAL, local, size);
+    }
+
+    ret = sitnl_send(&req.n, 0, 0, NULL, NULL);
+    if (ret == -EEXIST)
+    {
+        ret = 0;
+    }
+err:
+    return ret;
+}
+
+static int
+sitnl_addr_ptp_add(sa_family_t af_family, const char *iface,
+                   const inet_address_t *local,
+                   const inet_address_t *remote)
+{
+    int ifindex;
+
+    switch (af_family)
+    {
+        case AF_INET:
+        case AF_INET6:
+            break;
+
+        default:
+            return -EINVAL;
+    }
+
+    if (!iface)
+    {
+        msg(M_WARN, "%s: passed NULL interface", __func__);
+        return -EINVAL;
+    }
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN, "%s: cannot get ifindex for %s: %s", __func__, np(iface),
+            strerror(errno));
+        return -ENOENT;
+    }
+
+    return sitnl_addr_set(RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, ifindex,
+                          af_family, local, remote, 0);
+}
+
+static int
+sitnl_addr_ptp_del(sa_family_t af_family, const char *iface,
+                   const inet_address_t *local)
+{
+    int ifindex;
+
+    switch (af_family)
+    {
+        case AF_INET:
+        case AF_INET6:
+            break;
+
+        default:
+            return -EINVAL;
+    }
+
+    if (!iface)
+    {
+        msg(M_WARN, "%s: passed NULL interface", __func__);
+        return -EINVAL;
+    }
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: cannot get ifindex for %s", __func__, iface);
+        return -ENOENT;
+    }
+
+    return sitnl_addr_set(RTM_DELADDR, 0, ifindex, af_family, local, NULL, 0);
+}
+
+static int
+sitnl_route_set(int cmd, uint32_t flags, int ifindex, sa_family_t af_family,
+                const void *dst, int prefixlen,
+                const void *gw, enum rt_class_t table, int metric,
+                enum rt_scope_t scope, int protocol, int type)
+{
+    struct sitnl_route_req req;
+    int ret = -1, size;
+
+    CLEAR(req);
+
+    switch (af_family)
+    {
+        case AF_INET:
+            size = sizeof(in_addr_t);
+            break;
+
+        case AF_INET6:
+            size = sizeof(struct in6_addr);
+            break;
+
+        default:
+            return -EINVAL;
+    }
+
+    req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.r));
+    req.n.nlmsg_type = cmd;
+    req.n.nlmsg_flags = NLM_F_REQUEST | flags;
+
+    req.r.rtm_family = af_family;
+    req.r.rtm_scope = scope;
+    req.r.rtm_protocol = protocol;
+    req.r.rtm_type = type;
+    req.r.rtm_dst_len = prefixlen;
+
+    if (table < 256)
+    {
+        req.r.rtm_table = table;
+    }
+    else
+    {
+        req.r.rtm_table = RT_TABLE_UNSPEC;
+        SITNL_ADDATTR(&req.n, sizeof(req), RTA_TABLE, &table, 4);
+    }
+
+    if (dst)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), RTA_DST, dst, size);
+    }
+
+    if (gw)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), RTA_GATEWAY, gw, size);
+    }
+
+    if (ifindex > 0)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), RTA_OIF, &ifindex, 4);
+    }
+
+    if (metric > 0)
+    {
+        SITNL_ADDATTR(&req.n, sizeof(req), RTA_PRIORITY, &metric, 4);
+    }
+
+    ret = sitnl_send(&req.n, 0, 0, NULL, NULL);
+    if (ret == -EEXIST)
+    {
+        ret = 0;
+    }
+err:
+    return ret;
+}
+
+static int
+sitnl_addr_add(sa_family_t af_family, const char *iface,
+               const inet_address_t *addr, int prefixlen)
+{
+    int ifindex;
+
+    switch (af_family)
+    {
+        case AF_INET:
+        case AF_INET6:
+            break;
+
+        default:
+            return -EINVAL;
+    }
+
+    if (!iface)
+    {
+        msg(M_WARN, "%s: passed NULL interface", __func__);
+        return -EINVAL;
+    }
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: rtnl: cannot get ifindex for %s", __func__,
+            iface);
+        return -ENOENT;
+    }
+
+    return sitnl_addr_set(RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, ifindex,
+                          af_family, addr, NULL, prefixlen);
+}
+
+static int
+sitnl_addr_del(sa_family_t af_family, const char *iface, inet_address_t *addr,
+               int prefixlen)
+{
+    int ifindex;
+
+    switch (af_family)
+    {
+        case AF_INET:
+        case AF_INET6:
+            break;
+
+        default:
+            return -EINVAL;
+    }
+
+    if (!iface)
+    {
+        msg(M_WARN, "%s: passed NULL interface", __func__);
+        return -EINVAL;
+    }
+
+    ifindex = if_nametoindex(iface);
+    if (ifindex == 0)
+    {
+        msg(M_WARN | M_ERRNO, "%s: rtnl: cannot get ifindex for %s", __func__,
+            iface);
+        return -ENOENT;
+    }
+
+    return sitnl_addr_set(RTM_DELADDR, 0, ifindex, af_family, addr, NULL,
+                          prefixlen);
+}
+
+int
+net_addr_v4_add(openvpn_net_ctx_t *ctx, const char *iface,
+                const in_addr_t *addr, int prefixlen)
+{
+    inet_address_t addr_v4 = { 0 };
+    char buf[INET_ADDRSTRLEN];
+
+    if (!addr)
+    {
+        return -EINVAL;
+    }
+
+    addr_v4.ipv4 = htonl(*addr);
+
+    msg(M_INFO, "%s: %s/%d dev %s", __func__,
+        inet_ntop(AF_INET, &addr_v4.ipv4, buf, sizeof(buf)), prefixlen,iface);
+
+    return sitnl_addr_add(AF_INET, iface, &addr_v4, prefixlen);
+}
+
+int
+net_addr_v6_add(openvpn_net_ctx_t *ctx, const char *iface,
+                const struct in6_addr *addr, int prefixlen)
+{
+    inet_address_t addr_v6 = { 0 };
+    char buf[INET6_ADDRSTRLEN];
+
+    if (!addr)
+    {
+        return -EINVAL;
+    }
+
+    addr_v6.ipv6 = *addr;
+
+    msg(M_INFO, "%s: %s/%d dev %s", __func__,
+        inet_ntop(AF_INET6, &addr_v6.ipv6, buf, sizeof(buf)), prefixlen, iface);
+
+    return sitnl_addr_add(AF_INET6, iface, &addr_v6, prefixlen);
+}
+
+int
+net_addr_v4_del(openvpn_net_ctx_t *ctx, const char *iface,
+                const in_addr_t *addr, int prefixlen)
+{
+    inet_address_t addr_v4 = { 0 };
+    char buf[INET_ADDRSTRLEN];
+
+    if (!addr)
+    {
+        return -EINVAL;
+    }
+
+    addr_v4.ipv4 = htonl(*addr);
+
+    msg(M_INFO, "%s: %s dev %s", __func__,
+        inet_ntop(AF_INET, &addr_v4.ipv4, buf, sizeof(buf)), iface);
+
+    return sitnl_addr_del(AF_INET, iface, &addr_v4, prefixlen);
+}
+
+int
+net_addr_v6_del(openvpn_net_ctx_t *ctx, const char *iface,
+                const struct in6_addr *addr, int prefixlen)
+{
+    inet_address_t addr_v6 = { 0 };
+    char buf[INET6_ADDRSTRLEN];
+
+    if (!addr)
+    {
+        return -EINVAL;
+    }
+
+    addr_v6.ipv6 = *addr;
+
+    msg(M_INFO, "%s: %s/%d dev %s", __func__,
+        inet_ntop(AF_INET6, &addr_v6.ipv6, buf, sizeof(buf)), prefixlen, iface);
+
+    return sitnl_addr_del(AF_INET6, iface, &addr_v6, prefixlen);
+}
+
+int
+net_addr_ptp_v4_add(openvpn_net_ctx_t *ctx, const char *iface,
+                    const in_addr_t *local, const in_addr_t *remote)
+{
+    inet_address_t local_v4 = { 0 };
+    inet_address_t remote_v4 = { 0 };
+    char buf1[INET_ADDRSTRLEN];
+    char buf2[INET_ADDRSTRLEN];
+
+    if (!local)
+    {
+        return -EINVAL;
+    }
+
+    local_v4.ipv4 = htonl(*local);
+
+    if (remote)
+    {
+        remote_v4.ipv4 = htonl(*remote);
+    }
+
+    msg(M_INFO, "%s: %s peer %s dev %s", __func__,
+        inet_ntop(AF_INET, &local_v4.ipv4, buf1, sizeof(buf1)),
+        inet_ntop(AF_INET, &remote_v4.ipv4, buf2, sizeof(buf2)), iface);
+
+    return sitnl_addr_ptp_add(AF_INET, iface, &local_v4, &remote_v4);
+}
+
+int
+net_addr_ptp_v4_del(openvpn_net_ctx_t *ctx, const char *iface,
+                    const in_addr_t *local, const in_addr_t *remote)
+{
+    inet_address_t local_v4 = { 0 };
+    char buf[INET6_ADDRSTRLEN];
+
+
+    if (!local)
+    {
+        return -EINVAL;
+    }
+
+    local_v4.ipv4 = htonl(*local);
+
+    msg(M_INFO, "%s: %s dev %s", __func__,
+        inet_ntop(AF_INET, &local_v4.ipv4, buf, sizeof(buf)), iface);
+
+    return sitnl_addr_ptp_del(AF_INET, iface, &local_v4);
+}
+
+static int
+sitnl_route_add(const char *iface, sa_family_t af_family, const void *dst,
+                int prefixlen, const void *gw, uint32_t table, int metric)
+{
+    enum rt_scope_t scope = RT_SCOPE_UNIVERSE;
+    int ifindex = 0;
+
+    if (iface)
+    {
+        ifindex = if_nametoindex(iface);
+        if (ifindex == 0)
+        {
+            msg(M_WARN | M_ERRNO, "%s: rtnl: can't get ifindex for %s",
+                __func__, iface);
+            return -ENOENT;
+        }
+    }
+
+    if (table == 0)
+    {
+        table = RT_TABLE_MAIN;
+    }
+
+    if (!gw && iface)
+    {
+        scope = RT_SCOPE_LINK;
+    }
+
+    return sitnl_route_set(RTM_NEWROUTE, NLM_F_CREATE | NLM_F_REPLACE, ifindex,
+                           af_family, dst, prefixlen, gw, table, metric, scope,
+                           RTPROT_BOOT, RTN_UNICAST);
+}
+
+int
+net_route_v4_add(openvpn_net_ctx_t *ctx, const in_addr_t *dst, int prefixlen,
+                 const in_addr_t *gw, const char *iface,
+                 uint32_t table, int metric)
+{
+    in_addr_t *dst_ptr = NULL, *gw_ptr = NULL;
+    in_addr_t dst_be = 0, gw_be = 0;
+    char dst_str[INET_ADDRSTRLEN];
+    char gw_str[INET_ADDRSTRLEN];
+
+    if (dst)
+    {
+        dst_be = htonl(*dst);
+        dst_ptr = &dst_be;
+    }
+
+    if (gw)
+    {
+        gw_be = htonl(*gw);
+        gw_ptr = &gw_be;
+    }
+
+    msg(D_ROUTE, "%s: %s/%d via %s dev %s table %d metric %d", __func__,
+        inet_ntop(AF_INET, &dst_be, dst_str, sizeof(dst_str)),
+        prefixlen, inet_ntop(AF_INET, &gw_be, gw_str, sizeof(gw_str)),
+        np(iface), table, metric);
+
+    return sitnl_route_add(iface, AF_INET, dst_ptr, prefixlen, gw_ptr, table,
+                           metric);
+}
+
+int
+net_route_v6_add(openvpn_net_ctx_t *ctx, const struct in6_addr *dst,
+                 int prefixlen, const struct in6_addr *gw,
+                 const char *iface, uint32_t table, int metric)
+{
+    inet_address_t dst_v6 = { 0 };
+    inet_address_t gw_v6 = { 0 };
+    char dst_str[INET6_ADDRSTRLEN];
+    char gw_str[INET6_ADDRSTRLEN];
+
+    if (dst)
+    {
+        dst_v6.ipv6 = *dst;
+    }
+
+    if (gw)
+    {
+        gw_v6.ipv6 = *gw;
+    }
+
+    msg(D_ROUTE, "%s: %s/%d via %s dev %s table %d metric %d", __func__,
+        inet_ntop(AF_INET6, &dst_v6.ipv6, dst_str, sizeof(dst_str)),
+        prefixlen, inet_ntop(AF_INET6, &gw_v6.ipv6, gw_str, sizeof(gw_str)),
+        np(iface), table, metric);
+
+    return sitnl_route_add(iface, AF_INET6, dst, prefixlen, gw, table,
+                           metric);
+}
+
+static int
+sitnl_route_del(const char *iface, sa_family_t af_family, inet_address_t *dst,
+                int prefixlen, inet_address_t *gw, uint32_t table,
+                int metric)
+{
+    int ifindex = 0;
+
+    if (iface)
+    {
+        ifindex = if_nametoindex(iface);
+        if (ifindex == 0)
+        {
+            msg(M_WARN | M_ERRNO, "%s: rtnl: can't get ifindex for %s",
+                __func__, iface);
+            return -ENOENT;
+        }
+    }
+
+    if (table == 0)
+    {
+        table = RT_TABLE_MAIN;
+    }
+
+    return sitnl_route_set(RTM_DELROUTE, 0, ifindex, af_family, dst, prefixlen,
+                           gw, table, metric, RT_SCOPE_NOWHERE, 0, 0);
+}
+
+int
+net_route_v4_del(openvpn_net_ctx_t *ctx, const in_addr_t *dst, int prefixlen,
+                 const in_addr_t *gw, const char *iface, uint32_t table,
+                 int metric)
+{
+    inet_address_t dst_v4 = { 0 };
+    inet_address_t gw_v4 = { 0 };
+    char dst_str[INET_ADDRSTRLEN];
+    char gw_str[INET_ADDRSTRLEN];
+
+    if (dst)
+    {
+        dst_v4.ipv4 = htonl(*dst);
+    }
+
+    if (gw)
+    {
+        gw_v4.ipv4 = htonl(*gw);
+    }
+
+    msg(D_ROUTE, "%s: %s/%d via %s dev %s table %d metric %d", __func__,
+        inet_ntop(AF_INET, &dst_v4.ipv4, dst_str, sizeof(dst_str)),
+        prefixlen, inet_ntop(AF_INET, &gw_v4.ipv4, gw_str, sizeof(gw_str)),
+        np(iface), table, metric);
+
+    return sitnl_route_del(iface, AF_INET, &dst_v4, prefixlen, &gw_v4, table,
+                           metric);
+}
+
+int
+net_route_v6_del(openvpn_net_ctx_t *ctx, const struct in6_addr *dst,
+                 int prefixlen, const struct in6_addr *gw,
+                 const char *iface, uint32_t table, int metric)
+{
+    inet_address_t dst_v6 = { 0 };
+    inet_address_t gw_v6 = { 0 };
+    char dst_str[INET6_ADDRSTRLEN];
+    char gw_str[INET6_ADDRSTRLEN];
+
+    if (dst)
+    {
+        dst_v6.ipv6 = *dst;
+    }
+
+    if (gw)
+    {
+        gw_v6.ipv6 = *gw;
+    }
+
+    msg(D_ROUTE, "%s: %s/%d via %s dev %s table %d metric %d", __func__,
+        inet_ntop(AF_INET6, &dst_v6.ipv6, dst_str, sizeof(dst_str)),
+        prefixlen, inet_ntop(AF_INET6, &gw_v6.ipv6, gw_str, sizeof(gw_str)),
+        np(iface), table, metric);
+
+    return sitnl_route_del(iface, AF_INET6, &dst_v6, prefixlen, &gw_v6,
+                           table, metric);
+}
+
+#endif /* !ENABLE_SITNL */
+
+#endif /* TARGET_LINUX */