tomato/toxcore/LAN_discovery.c
Green Sky aae086cc65 Squashed 'external/toxcore/c-toxcore/' changes from e2c01e457b..b03b571272
b03b571272 fix: flaky tcp test This only fixes the symptoms, not the real problem. Sometimes or consistently on some platforms a socket might need a moment before it can be written to.
32e67ab4c2 cleanup: use typedef for private message ID's in callback
7b1db6adc1 feat: add message IDs to private group messages
99e0bcc27d refactor: Observers/ignored peers can now send and receive custom packets
b3c3c49d26 fix: Disable IPv6 in Windows cross-compilation tests
e742deddff feat: Check hashes of Windows dependencies when cross-compiling
dfb9a0b02b fix: Test the current Windows Dockerfile, not an old Dockerhub image
14de93ccec chore: Use WineHQ's Wine as Debian Bookworm's crashes
ed37616249 docs: Update the Windows cross-compilation section
9bb79c174f cleanup: Remove a couple of unnecessary misc_tools dependencies
19475adb70 chore: Statically link OpenMP into the cracker fun util on Windows
1be311e51f feat: Build the fun utils when cross-compiling to Windows
88133f8446 chore: Strip Windows binaries
3cc0ae7535 refactor: Copy over all of the required static dependencies
c4fa8f7fb1 feat: Generate .def, .exp and .lib files when building for Windows
74bbac5363 feat: Let CMake create the dll instead of doing so ourselves
246642e9ae feat: Harden Windows cross-compilation
8d431c0d11 chore: Bump Windows build dependency versions
e519f7998b fix: Remove unnecessary wsock32 dependency on Windows
ed2b60c217 chore: Use a specific non-broken slimcc version.
d7f21010a1 chore: Update github actions.
e71a68b7f2 docs: Update the list of CMake options
77e08876ff chore: Remove mod and founder from group API naming scheme
12bc042767 docs: add the experimental api build option to INSTALL.md
e1fa5cae96 refactor: Rename Queries to Query to align with other enums.
be82a3ea30 fix: Correct type for conference offline peer numbers.
0627c36716 test: Add pkgsrc build.
92578afe4b test: Add FreeBSD VM action on GitHub.
52ece0f57b test: Build toxcore on NetBSD (VM).
3fe8ee2c11 chore: Only install tox_private.h on request.
9a8dfa06ab fix: save_compatibility_test failing on big-endian systems
86f5e55578 fix: Don't serve files from websockify.
710eb674a5 fix: Correctly pass extended public keys to group moderation code.
021db7031c refactor: Use `struct`s for extended public/secret keys.
a1e999fd80 chore: Compile libsodium reference implementation with compcert.
fbe3c19cf5 cleanup: correct a few nullable annotations
623e3ee5c3 cleanup: Don't use `memcpy` to cast arbitrary `struct`s to `uint8_t[]`.
c71567dc18 fix: Pass array, not array pointer, to `memcmp`.
9b46a08144 cleanup: Never pass `void*` directly to `memcpy`.
5d7b7a7bbc refactor: Use tox rng to seed the keypair generation.
961891d568 cleanup: Small improvements found by PVS Studio.
8201019f0d chore: Disable NGC saving by default, enable through Tox_Options.
5dd9ee3f65 cleanup: Replace pointer arithmetic with explicit `&arr[i]`.
ca4606d49d refactor: Use strong typedef for NGC peer id.
442213b722 cleanup: Simplify custom packet length check in NGC.
08d3393def fix: Correct a few potential null derefs in bootstrap daemon.
b9877b32b0 fix: Add missing memunlock of local variable when it goes out of scope.
dab5fe44b9 fix: Zero out stack-allocated secret key before return.
f058103299 refactor: Make prune_gc_sanctions_list more obviously correct.
3ba7a0dec9 docs: Add static analysis tool list to README.
8d0811a0f3 docs: Run prettier-markdown on markdown files.
969e3a2bfc refactor: Fix network test not using the strong typedef
93c83fbc7c refactor: Use strong typedef instead of struct for `Socket`.
9fe18b176f fix: Fix some false positive from PVS Studio.
7c44379ccb cleanup: Check that WINXP macro exists before comparing it.
5c93231bef refactor: Make tox mutex non-recursive.
aacff73939 docs: Fix up doxyfile.
d55fc85ff5 docs: Add more documentation to crypto_core.
5bdaaaedb6 refactor: Remove `Tox *` from `tox_dispatch`.
e202341e76 refactor: Don't rely on tox_dispatch passing tox in tests.
34df938f52 chore: Use C++ mode for clang-tidy.
8b05296a78 chore: Check that both gtest and gmock exist for tests.
42010660e1 test: Add slimcc compiler compatibility test.
b473630321 chore: Add some comments to the astyle config.
b7404f24f6 cleanup: Remove implicit bool conversions.
4e2dba4d9f chore: Reformat sources with astyle.
4359e3a6bc chore: Rename C++ headers to .hh suffixes.
0c05566e58 cleanup: Further `#include` cleanups.
8d29935b7a chore: Only check the bootstrap daemon checksum on release.
f70e588bc6 cleanup: Add more `const` where possible.
511bfe39c8 cleanup: Use Bazel modules to enforce proper `#include` hygiene.
1710a0d091 refactor: Move pack/unpack `IP_Port` from DHT into network module.
a975943564 chore: Really fix coverage docker image build.
c08409390f chore: Fix post-submit coverage image.
39aadf8922 fix: Don't use `memcmp` to compare `IP_Port`s.
d94246a906 fix: partially fix a bug that prevented group part messages from sending.
eeaa039222 chore: Fix rpm build; add a CI check for it.
8328449c1a chore: Speed up docker builds a bit by reducing layer count.
d6d67d56f3 cleanup: Add `const` where possible in auto tests.
6aa9e6850d cleanup: Minor cleanup of event unpack code.
bdf460a3a9 refactor: Rename `system_{memory,...}` to `os_{memory,...}`.
203e1af81e fix: a few off by one errors in group autotests
5c093c4888 cleanup: Remove all uses of `SIZEOF_VLA`.
662c2140f3 test: Add goblint static analyser.
8f07755834 cleanup: Use `memzero(x, s)` instead of `memset(x, 0, s)`.
a7258e40cf cleanup: Use explicit 0 instead of `PACKET_ID_PADDING`.
6370d0f15d cleanup: Expand the `Tox_Options` accessor macros.
14a1a0b9bd cleanup: Remove plan9 support.
a05dccad13 test: Add a simple new/delete test for Tox.
1cdcf938b9 cleanup: Add comment after every `#endif`.
ba99d4dc4b test: Fix comment I broke in the events test PR.
e07248debb refactor: Migrate auto_tests to new events API.
bdd42b5452 refactor: Add common msgpack array packer with callback.
3c659f5288 cleanup: Rename group to conference in groupav documentation.
89957be230 cleanup: Ensure handler params are named after callback params.
c650d9d345 refactor: Pass `this` pointer as first param to s11n callbacks.
e7fb91ddb8 refactor: Allow NULL pointers for byte arrays in events.
5e2c8cabc1 cleanup: make some improvements to group moderation test
259de4867e cleanup: Remove `bin_pack_{new,free}`.
21a8ff5895 cleanup: skip a do_gc iteration before removing peers marked for deletion
16809dc36e feat: Add dht_get_nodes_response event to the events system.

git-subtree-dir: external/toxcore/c-toxcore
git-subtree-split: b03b5712720de9a9901ea12fd741f177327a7021
2024-03-07 23:12:55 +01:00

387 lines
10 KiB
C

/* SPDX-License-Identifier: GPL-3.0-or-later
* Copyright © 2016-2018 The TokTok team.
* Copyright © 2013 Tox project.
*/
/**
* LAN discovery implementation.
*/
#include "LAN_discovery.h"
#include <stdlib.h>
#if defined(_WIN32) || defined(__WIN32__) || defined(WIN32)
// The mingw32/64 Windows library warns about including winsock2.h after
// windows.h even though with the above it's a valid thing to do. So, to make
// mingw32 headers happy, we include winsock2.h first.
#include <winsock2.h>
#include <windows.h>
#include <ws2tcpip.h>
#include <iphlpapi.h>
#endif /* WIN32 */
#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
#include <netinet/in.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#endif /* Linux/BSD */
#ifdef __linux__
#include <linux/if.h>
#endif /* Linux */
#if defined(__FreeBSD__) || defined(__DragonFly__)
#include <net/if.h>
#endif /* BSD */
#include "attributes.h"
#include "ccompat.h"
#include "crypto_core.h"
#include "network.h"
#define MAX_INTERFACES 16
struct Broadcast_Info {
uint32_t count;
IP ips[MAX_INTERFACES];
};
#if defined(_WIN32) || defined(__WIN32__) || defined(WIN32)
non_null()
static Broadcast_Info *fetch_broadcast_info(const Network *ns)
{
Broadcast_Info *broadcast = (Broadcast_Info *)calloc(1, sizeof(Broadcast_Info));
if (broadcast == nullptr) {
return nullptr;
}
IP_ADAPTER_INFO *adapter_info = (IP_ADAPTER_INFO *)malloc(sizeof(IP_ADAPTER_INFO));
if (adapter_info == nullptr) {
free(broadcast);
return nullptr;
}
unsigned long out_buf_len = sizeof(IP_ADAPTER_INFO);
if (GetAdaptersInfo(adapter_info, &out_buf_len) == ERROR_BUFFER_OVERFLOW) {
free(adapter_info);
IP_ADAPTER_INFO *new_adapter_info = (IP_ADAPTER_INFO *)malloc(out_buf_len);
if (new_adapter_info == nullptr) {
free(broadcast);
return nullptr;
}
adapter_info = new_adapter_info;
}
const int ret = GetAdaptersInfo(adapter_info, &out_buf_len);
if (ret == NO_ERROR) {
IP_ADAPTER_INFO *adapter = adapter_info;
while (adapter != nullptr) {
IP gateway = {0};
IP subnet_mask = {0};
if (addr_parse_ip(adapter->IpAddressList.IpMask.String, &subnet_mask)
&& addr_parse_ip(adapter->GatewayList.IpAddress.String, &gateway)) {
if (net_family_is_ipv4(gateway.family) && net_family_is_ipv4(subnet_mask.family)) {
IP *ip = &broadcast->ips[broadcast->count];
ip->family = net_family_ipv4();
const uint32_t gateway_ip = net_ntohl(gateway.ip.v4.uint32);
const uint32_t subnet_ip = net_ntohl(subnet_mask.ip.v4.uint32);
const uint32_t broadcast_ip = gateway_ip + ~subnet_ip - 1;
ip->ip.v4.uint32 = net_htonl(broadcast_ip);
++broadcast->count;
if (broadcast->count >= MAX_INTERFACES) {
break;
}
}
}
adapter = adapter->Next;
}
}
if (adapter_info != nullptr) {
free(adapter_info);
}
return broadcast;
}
#elif !defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && (defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__))
non_null()
static Broadcast_Info *fetch_broadcast_info(const Network *ns)
{
Broadcast_Info *broadcast = (Broadcast_Info *)calloc(1, sizeof(Broadcast_Info));
if (broadcast == nullptr) {
return nullptr;
}
/* Not sure how many platforms this will run on,
* so it's wrapped in `__linux__` for now.
* Definitely won't work like this on Windows...
*/
const Socket sock = net_socket(ns, net_family_ipv4(), TOX_SOCK_STREAM, 0);
if (!sock_valid(sock)) {
free(broadcast);
return nullptr;
}
/* Configure ifconf for the ioctl call. */
struct ifreq i_faces[MAX_INTERFACES] = {{{0}}};
struct ifconf ifc;
ifc.ifc_buf = (char *)i_faces;
ifc.ifc_len = sizeof(i_faces);
if (ioctl(net_socket_to_native(sock), SIOCGIFCONF, &ifc) < 0) {
kill_sock(ns, sock);
free(broadcast);
return nullptr;
}
/* `ifc.ifc_len` is set by the `ioctl()` to the actual length used.
* On usage of the complete array the call should be repeated with
* a larger array, not done (640kB and 16 interfaces shall be
* enough, for everybody!)
*/
const int n = ifc.ifc_len / sizeof(struct ifreq);
for (int i = 0; i < n; ++i) {
/* there are interfaces with are incapable of broadcast */
if (ioctl(net_socket_to_native(sock), SIOCGIFBRDADDR, &i_faces[i]) < 0) {
continue;
}
/* moot check: only AF_INET returned (backwards compat.) */
if (i_faces[i].ifr_broadaddr.sa_family != AF_INET) {
continue;
}
const struct sockaddr_in *sock4 = (const struct sockaddr_in *)(void *)&i_faces[i].ifr_broadaddr;
if (broadcast->count >= MAX_INTERFACES) {
break;
}
IP *ip = &broadcast->ips[broadcast->count];
ip->family = net_family_ipv4();
ip->ip.v4.uint32 = sock4->sin_addr.s_addr;
if (ip->ip.v4.uint32 == 0) {
continue;
}
++broadcast->count;
}
kill_sock(ns, sock);
return broadcast;
}
#else // TODO(irungentoo): Other platforms?
non_null()
static Broadcast_Info *fetch_broadcast_info(const Network *ns)
{
return (Broadcast_Info *)calloc(1, sizeof(Broadcast_Info));
}
#endif /* platforms */
/** @brief Send packet to all IPv4 broadcast addresses
*
* @retval true if sent to at least one broadcast target.
* @retval false on failure to find any valid broadcast target.
*/
non_null()
static bool send_broadcasts(const Networking_Core *net, const Broadcast_Info *broadcast, uint16_t port,
const uint8_t *data, uint16_t length)
{
if (broadcast->count == 0) {
return false;
}
for (uint32_t i = 0; i < broadcast->count; ++i) {
IP_Port ip_port;
ip_port.ip = broadcast->ips[i];
ip_port.port = port;
sendpacket(net, &ip_port, data, length);
}
return true;
}
/** Return the broadcast ip. */
static IP broadcast_ip(Family family_socket, Family family_broadcast)
{
IP ip;
ip_reset(&ip);
if (net_family_is_ipv6(family_socket)) {
if (net_family_is_ipv6(family_broadcast)) {
ip.family = net_family_ipv6();
/* `FF02::1` is - according to RFC 4291 - multicast all-nodes link-local */
/* `FE80::*:` MUST be exact, for that we would need to look over all
* interfaces and check in which status they are */
ip.ip.v6.uint8[0] = 0xFF;
ip.ip.v6.uint8[1] = 0x02;
ip.ip.v6.uint8[15] = 0x01;
} else if (net_family_is_ipv4(family_broadcast)) {
ip.family = net_family_ipv6();
ip.ip.v6 = get_ip6_broadcast();
}
} else if (net_family_is_ipv4(family_socket) && net_family_is_ipv4(family_broadcast)) {
ip.family = net_family_ipv4();
ip.ip.v4 = get_ip4_broadcast();
}
return ip;
}
non_null()
static bool ip4_is_local(const IP4 *ip4)
{
/* Loopback. */
return ip4->uint8[0] == 127;
}
/**
* Is IP a local ip or not.
*/
bool ip_is_local(const IP *ip)
{
if (net_family_is_ipv4(ip->family)) {
return ip4_is_local(&ip->ip.v4);
}
/* embedded IPv4-in-IPv6 */
if (ipv6_ipv4_in_v6(&ip->ip.v6)) {
IP4 ip4;
ip4.uint32 = ip->ip.v6.uint32[3];
return ip4_is_local(&ip4);
}
/* localhost in IPv6 (::1) */
return ip->ip.v6.uint64[0] == 0 && ip->ip.v6.uint32[2] == 0 && ip->ip.v6.uint32[3] == net_htonl(1);
}
non_null()
static bool ip4_is_lan(const IP4 *ip4)
{
/* 10.0.0.0 to 10.255.255.255 range. */
if (ip4->uint8[0] == 10) {
return true;
}
/* 172.16.0.0 to 172.31.255.255 range. */
if (ip4->uint8[0] == 172 && ip4->uint8[1] >= 16 && ip4->uint8[1] <= 31) {
return true;
}
/* 192.168.0.0 to 192.168.255.255 range. */
if (ip4->uint8[0] == 192 && ip4->uint8[1] == 168) {
return true;
}
/* 169.254.1.0 to 169.254.254.255 range. */
if (ip4->uint8[0] == 169 && ip4->uint8[1] == 254 && ip4->uint8[2] != 0
&& ip4->uint8[2] != 255) {
return true;
}
/* RFC 6598: 100.64.0.0 to 100.127.255.255 (100.64.0.0/10)
* (shared address space to stack another layer of NAT) */
return (ip4->uint8[0] == 100) && ((ip4->uint8[1] & 0xC0) == 0x40);
}
bool ip_is_lan(const IP *ip)
{
if (ip_is_local(ip)) {
return true;
}
if (net_family_is_ipv4(ip->family)) {
return ip4_is_lan(&ip->ip.v4);
}
if (net_family_is_ipv6(ip->family)) {
/* autogenerated for each interface: `FE80::*` (up to `FEBF::*`)
* `FF02::1` is - according to RFC 4291 - multicast all-nodes link-local */
if (((ip->ip.v6.uint8[0] == 0xFF) && (ip->ip.v6.uint8[1] < 3) && (ip->ip.v6.uint8[15] == 1)) ||
((ip->ip.v6.uint8[0] == 0xFE) && ((ip->ip.v6.uint8[1] & 0xC0) == 0x80))) {
return true;
}
/* embedded IPv4-in-IPv6 */
if (ipv6_ipv4_in_v6(&ip->ip.v6)) {
IP4 ip4;
ip4.uint32 = ip->ip.v6.uint32[3];
return ip4_is_lan(&ip4);
}
}
return false;
}
bool lan_discovery_send(const Networking_Core *net, const Broadcast_Info *broadcast, const uint8_t *dht_pk,
uint16_t port)
{
if (broadcast == nullptr) {
return false;
}
uint8_t data[CRYPTO_PUBLIC_KEY_SIZE + 1];
data[0] = NET_PACKET_LAN_DISCOVERY;
pk_copy(data + 1, dht_pk);
send_broadcasts(net, broadcast, port, data, 1 + CRYPTO_PUBLIC_KEY_SIZE);
bool res = false;
IP_Port ip_port;
ip_port.port = port;
/* IPv6 multicast */
if (net_family_is_ipv6(net_family(net))) {
ip_port.ip = broadcast_ip(net_family_ipv6(), net_family_ipv6());
if (ip_isset(&ip_port.ip) && sendpacket(net, &ip_port, data, 1 + CRYPTO_PUBLIC_KEY_SIZE) > 0) {
res = true;
}
}
/* IPv4 broadcast (has to be IPv4-in-IPv6 mapping if socket is IPv6 */
ip_port.ip = broadcast_ip(net_family(net), net_family_ipv4());
if (ip_isset(&ip_port.ip) && sendpacket(net, &ip_port, data, 1 + CRYPTO_PUBLIC_KEY_SIZE) > 0) {
res = true;
}
return res;
}
Broadcast_Info *lan_discovery_init(const Network *ns)
{
return fetch_broadcast_info(ns);
}
void lan_discovery_kill(Broadcast_Info *broadcast)
{
free(broadcast);
}