Adding upstream version 6.0.4-dfsg.upstream/6.0.4-dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 323 insertions, 0 deletions

diff --git a/src/VBox/NetworkServices/NAT/pxremap.c b/src/VBox/NetworkServices/NAT/pxremap.c
new file mode 100644
index 00000000..5332fabf
--- /dev/null
+++ b/src/VBox/NetworkServices/NAT/pxremap.c
@@ -0,0 +1,323 @@
+/* $Id: pxremap.c $ */
+/** @file
+ * NAT Network - Loopback remapping.
+ */
+
+/*
+ * Copyright (C) 2013-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+/*
+ * This file contains functions pertinent to magic address remapping.
+ *
+ * We want to expose host's loopback interfaces to the guest by
+ * mapping them to the addresses from the same prefix/subnet, so if,
+ * for example proxy interface is 10.0.2.1, we redirect traffic to
+ * 10.0.2.2 to host's 127.0.0.1 loopback.  If need be, we may extend
+ * this to provide additional mappings, e.g. 127.0.1.1 loopback
+ * address is used on Ubuntu 12.10+ for NetworkManager's dnsmasq.
+ *
+ * Ditto for IPv6, except that IPv6 only has one loopback address.
+ */
+#define LOG_GROUP LOG_GROUP_NAT_SERVICE
+
+#include "winutils.h"
+#include "pxremap.h"
+#include "proxy.h"
+
+#include "lwip/netif.h"
+#include "netif/etharp.h"       /* proxy arp hook */
+
+#include "lwip/ip4.h"           /* IPv4 divert hook */
+#include "lwip/ip6.h"           /* IPv6 divert hook */
+
+#include <string.h>
+
+
+/**
+ * Check if "dst" is an IPv4 address that proxy remaps to host's
+ * loopback.
+ */
+static int
+proxy_ip4_is_mapped_loopback(struct netif *netif, const ip_addr_t *dst, ip_addr_t *lo)
+{
+    u32_t off;
+    const struct ip4_lomap *lomap;
+    size_t i;
+
+    LWIP_ASSERT1(dst != NULL);
+
+    if (g_proxy_options->lomap_desc == NULL) {
+        return 0;
+    }
+
+    if (!ip_addr_netcmp(dst, &netif->ip_addr, &netif->netmask)) {
+        return 0;
+    }
+
+    /* XXX: TODO: check netif is a proxying netif! */
+
+    off = ntohl(ip4_addr_get_u32(dst) & ~ip4_addr_get_u32(&netif->netmask));
+    lomap = g_proxy_options->lomap_desc->lomap;
+    for (i = 0; i < g_proxy_options->lomap_desc->num_lomap; ++i) {
+        if (off == lomap[i].off) {
+            if (lo != NULL) {
+                ip_addr_copy(*lo, lomap[i].loaddr);
+            }
+            return 1;
+        }
+    }
+    return 0;
+}
+
+
+#if ARP_PROXY
+/**
+ * Hook function for etharp_arp_input() - returns true to cause proxy
+ * ARP reply to be generated for "dst".
+ */
+int
+pxremap_proxy_arp(struct netif *netif, ip_addr_t *dst)
+{
+    return proxy_ip4_is_mapped_loopback(netif, dst, NULL);
+}
+#endif /* ARP_PROXY */
+
+
+/**
+ * Hook function for ip_forward() - returns true to divert packets to
+ * "dst" to proxy (instead of forwarding them via "netif" or dropping).
+ */
+int
+pxremap_ip4_divert(struct netif *netif, ip_addr_t *dst)
+{
+    return proxy_ip4_is_mapped_loopback(netif, dst, NULL);
+}
+
+
+/**
+ * Mapping from local network to loopback for outbound connections.
+ *
+ * Copy "src" to "dst" with ip_addr_set(dst, src), but if "src" is a
+ * local network address that maps host's loopback address, copy
+ * loopback address to "dst".
+ */
+int
+pxremap_outbound_ip4(ip_addr_t *dst, ip_addr_t *src)
+{
+    struct netif *netif;
+
+    LWIP_ASSERT1(dst != NULL);
+    LWIP_ASSERT1(src != NULL);
+
+    for (netif = netif_list; netif != NULL; netif = netif->next) {
+        if (netif_is_up(netif) /* && this is a proxy netif */) {
+            if (proxy_ip4_is_mapped_loopback(netif, src, dst)) {
+                return PXREMAP_MAPPED;
+            }
+        }
+    }
+
+    /* not remapped, just copy src */
+    ip_addr_set(dst, src);
+    return PXREMAP_ASIS;
+}
+
+
+/**
+ * Mapping from loopback to local network for inbound (port-forwarded)
+ * connections.
+ *
+ * Copy "src" to "dst" with ip_addr_set(dst, src), but if "src" is a
+ * host's loopback address, copy local network address that maps it to
+ * "dst".
+ */
+int
+pxremap_inbound_ip4(ip_addr_t *dst, ip_addr_t *src)
+{
+    struct netif *netif;
+    const struct ip4_lomap *lomap;
+    unsigned int i;
+
+    if (ip4_addr1(src) != IP_LOOPBACKNET) {
+        ip_addr_set(dst, src);
+        return PXREMAP_ASIS;
+    }
+
+    if (g_proxy_options->lomap_desc == NULL) {
+        return PXREMAP_FAILED;
+    }
+
+#if 0 /* ?TODO: with multiple interfaces we need to consider fwspec::dst */
+    netif = ip_route(target);
+    if (netif == NULL) {
+        return PXREMAP_FAILED;
+    }
+#else
+    netif = netif_list;
+    LWIP_ASSERT1(netif != NULL);
+    LWIP_ASSERT1(netif->next == NULL);
+#endif
+
+    lomap = g_proxy_options->lomap_desc->lomap;
+    for (i = 0; i < g_proxy_options->lomap_desc->num_lomap; ++i) {
+        if (ip_addr_cmp(src, &lomap[i].loaddr)) {
+            ip_addr_t net;
+
+            ip_addr_get_network(&net, &netif->ip_addr, &netif->netmask);
+            ip4_addr_set_u32(dst,
+                             htonl(ntohl(ip4_addr_get_u32(&net))
+                                   + lomap[i].off));
+            return PXREMAP_MAPPED;
+        }
+    }
+
+    return PXREMAP_FAILED;
+}
+
+
+static int
+proxy_ip6_is_mapped_loopback(struct netif *netif, ip6_addr_t *dst)
+{
+    int i;
+
+    /* XXX: TODO: check netif is a proxying netif! */
+
+    LWIP_ASSERT1(dst != NULL);
+
+    for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
+        if (ip6_addr_ispreferred(netif_ip6_addr_state(netif, i))
+            && ip6_addr_isuniquelocal(netif_ip6_addr(netif, i)))
+        {
+            ip6_addr_t *ifaddr = netif_ip6_addr(netif, i);
+            if (memcmp(dst, ifaddr, sizeof(ip6_addr_t) - 1) == 0
+                && ((IP6_ADDR_BLOCK8(dst) & 0xff)
+                    == (IP6_ADDR_BLOCK8(ifaddr) & 0xff) + 1))
+            {
+                return 1;
+            }
+        }
+    }
+
+    return 0;
+}
+
+
+/**
+ * Hook function for nd6_input() - returns true to cause proxy NA
+ * reply to be generated for "dst".
+ */
+int
+pxremap_proxy_na(struct netif *netif, ip6_addr_t *dst)
+{
+    return proxy_ip6_is_mapped_loopback(netif, dst);
+}
+
+
+/**
+ * Hook function for ip6_forward() - returns true to divert packets to
+ * "dst" to proxy (instead of forwarding them via "netif" or dropping).
+ */
+int
+pxremap_ip6_divert(struct netif *netif, ip6_addr_t *dst)
+{
+    return proxy_ip6_is_mapped_loopback(netif, dst);
+}
+
+
+/**
+ * Mapping from local network to loopback for outbound connections.
+ *
+ * Copy "src" to "dst" with ip6_addr_set(dst, src), but if "src" is a
+ * local network address that maps host's loopback address, copy IPv6
+ * loopback address to "dst".
+ */
+int
+pxremap_outbound_ip6(ip6_addr_t *dst, ip6_addr_t *src)
+{
+    struct netif *netif;
+    int i;
+
+    LWIP_ASSERT1(dst != NULL);
+    LWIP_ASSERT1(src != NULL);
+
+    for (netif = netif_list; netif != NULL; netif = netif->next) {
+        if (!netif_is_up(netif) /* || this is not a proxy netif */) {
+            continue;
+        }
+
+        for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
+            if (ip6_addr_ispreferred(netif_ip6_addr_state(netif, i))
+                && ip6_addr_isuniquelocal(netif_ip6_addr(netif, i)))
+            {
+                ip6_addr_t *ifaddr = netif_ip6_addr(netif, i);
+                if (memcmp(src, ifaddr, sizeof(ip6_addr_t) - 1) == 0
+                    && ((IP6_ADDR_BLOCK8(src) & 0xff)
+                        == (IP6_ADDR_BLOCK8(ifaddr) & 0xff) + 1))
+                {
+                    ip6_addr_set_loopback(dst);
+                    return PXREMAP_MAPPED;
+                }
+            }
+        }
+    }
+
+    /* not remapped, just copy src */
+    ip6_addr_set(dst, src);
+    return PXREMAP_ASIS;
+}
+
+
+/**
+ * Mapping from loopback to local network for inbound (port-forwarded)
+ * connections.
+ *
+ * Copy "src" to "dst" with ip6_addr_set(dst, src), but if "src" is a
+ * host's loopback address, copy local network address that maps it to
+ * "dst".
+ */
+int
+pxremap_inbound_ip6(ip6_addr_t *dst, ip6_addr_t *src)
+{
+    ip6_addr_t loopback;
+    struct netif *netif;
+    int i;
+
+    ip6_addr_set_loopback(&loopback);
+    if (!ip6_addr_cmp(src, &loopback)) {
+        ip6_addr_set(dst, src);
+        return PXREMAP_ASIS;
+    }
+
+#if 0  /* ?TODO: with multiple interfaces we need to consider fwspec::dst */
+    netif = ip6_route_fwd(target);
+    if (netif == NULL) {
+        return PXREMAP_FAILED;
+    }
+#else
+    netif = netif_list;
+    LWIP_ASSERT1(netif != NULL);
+    LWIP_ASSERT1(netif->next == NULL);
+#endif
+
+    for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; ++i) {
+        ip6_addr_t *ifaddr = netif_ip6_addr(netif, i);
+        if (ip6_addr_ispreferred(netif_ip6_addr_state(netif, i))
+            && ip6_addr_isuniquelocal(ifaddr))
+        {
+            ip6_addr_set(dst, ifaddr);
+            ++((u8_t *)&dst->addr[3])[3];
+            return PXREMAP_MAPPED;
+        }
+    }
+
+    return PXREMAP_FAILED;
+}