tunsafe-clang15/wireguard_config.cpp
Ludvig Strigeus cf92ac7a0c Updates for TunSafe 1.4-rc1
1.Subfolders in the Config/ directory now show up as submenus.
2.Added a way to run TunSafe as a Windows Service.
  Foreground Mode: The service will disconnect when TunSafe closes.
  Background Mode: The service will stay connected in the background.
  No longer required to run the TunSafe client as Admin as long as
  the service is running.
3.New config setting [Interface].ExcludedIPs to configure IPs that
  should not be routed through TunSafe.
4.Can now automatically start TunSafe when Windows starts
5.New UI with tabs and graphs
6.Cache DNS queries to ensure DNS will succeed if connection fails
7.Recreate tray icon when explorer.exe restarts
8.Renamed window title to TunSafe instead of TunSafe VPN Client
9.Main window is now resizable
10.Disallow roaming endpoint when using AllowedIPs=0.0.0.0/0
   Only the original endpoint is added in the routing table so
   this would result in an endless loop of packets.
11.Display approximate Wireguard framing overhead in stats
12.Preparations for protocol handling with multiple threads
13.Delete the routes we made when disconnecting
14.Fix error message about unable to delete a route when connecting
2018-08-12 03:30:06 +02:00

527 lines
14 KiB
C++

// SPDX-License-Identifier: AGPL-1.0-only
// Copyright (C) 2018 Ludvig Strigeus <info@tunsafe.com>. All Rights Reserved.
#include "stdafx.h"
#include "wireguard_config.h"
#include "netapi.h"
#include "tunsafe_endian.h"
#include "wireguard.h"
#include "util.h"
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <vector>
#if defined(OS_POSIX)
#include <unistd.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <netdb.h>
#endif
#if defined(OS_WIN)
#include "network_win32_dnsblock.h"
#endif
const char *print_ip_prefix(char buf[kSizeOfAddress], int family, const void *ip, int prefixlen) {
if (!inet_ntop(family, ip, buf, kSizeOfAddress - 8)) {
memcpy(buf, "unknown", 8);
}
if (prefixlen >= 0)
snprintf(buf + strlen(buf), 8, "/%d", prefixlen);
return buf;
}
char *PrintIpAddr(const IpAddr &addr, char buf[kSizeOfAddress]) {
if (addr.sin.sin_family == AF_INET) {
print_ip_prefix(buf, addr.sin.sin_family, &addr.sin.sin_addr, -1);
} else if (addr.sin.sin_family == AF_INET) {
print_ip_prefix(buf, addr.sin.sin_family, &addr.sin6.sin6_addr, -1);
} else {
buf[0] = 0;
}
return buf;
}
struct Addr {
byte addr[4];
uint8 cidr;
};
static bool ParseCidrAddr(char *s, WgCidrAddr *out) {
char *slash = strchr(s, '/');
if (!slash)
return false;
*slash = 0;
int e = atoi(slash + 1);
if (e < 0) return false;
if (inet_pton(AF_INET, s, out->addr) == 1) {
if (e > 32) return false;
out->cidr = e;
out->size = 32;
return true;
}
if (inet_pton(AF_INET6, s, out->addr) == 1) {
if (e > 128) return false;
out->cidr = e;
out->size = 128;
return true;
}
return false;
}
DnsResolver::DnsResolver(DnsBlocker *dns_blocker) {
dns_blocker_ = dns_blocker;
abort_flag_ = false;
}
DnsResolver::~DnsResolver() {
}
void DnsResolver::ClearCache() {
cache_.clear();
}
bool DnsResolver::Resolve(const char *hostname, IpAddr *result) {
int attempt = 0;
static const uint8 retry_delays[] = {1, 2, 3, 5, 10};
char buf[kSizeOfAddress];
memset(result, 0, sizeof(IpAddr));
if (inet_pton(AF_INET6, hostname, &result->sin6.sin6_addr) == 1) {
result->sin.sin_family = AF_INET6;
return true;
}
if (inet_pton(AF_INET, hostname, &result->sin.sin_addr) == 1) {
result->sin.sin_family = AF_INET;
return true;
}
// First check cache
for (auto it = cache_.begin(); it != cache_.end(); ++it) {
if (it->name == hostname) {
*result = it->ip;
RINFO("Resolved %s to %s%s", hostname, PrintIpAddr(*result, buf), " (cached)");
return true;
}
}
#if defined(OS_WIN)
// Then disable dns blocker (otherwise the windows dns client service can't resolve)
if (dns_blocker_ && dns_blocker_->IsActive()) {
RINFO("Disabling DNS blocker to resolve %s", hostname);
dns_blocker_->RestoreDns();
}
#endif // defined(OS_WIN)
for (;;) {
hostent *he = gethostbyname(hostname);
if (abort_flag_)
return false;
if (he) {
result->sin.sin_family = AF_INET;
result->sin.sin_port = 0;
memcpy(&result->sin.sin_addr, he->h_addr_list[0], 4);
// add to cache
cache_.emplace_back(hostname, *result);
RINFO("Resolved %s to %s%s", hostname, PrintIpAddr(*result, buf), "");
return true;
}
RINFO("Unable to resolve %s. Trying again in %d second(s)", hostname, retry_delays[attempt]);
OsInterruptibleSleep(retry_delays[attempt] * 1000);
if (abort_flag_)
return false;
if (attempt != ARRAY_SIZE(retry_delays) - 1)
attempt++;
}
}
static bool ParseSockaddrInWithPort(char *s, IpAddr *sin, DnsResolver *resolver) {
memset(sin, 0, sizeof(IpAddr));
if (*s == '[') {
char *end = strchr(s, ']');
if (end == NULL)
return false;
*end = 0;
if (inet_pton(AF_INET6, s + 1, &sin->sin6.sin6_addr) != 1)
return false;
char *x = strchr(end + 1, ':');
if (!x)
return false;
sin->sin.sin_family = AF_INET6;
sin->sin.sin_port = htons(atoi(x + 1));
return true;
}
char *x = strchr(s, ':');
if (!x) return false;
*x = 0;
if (!resolver->Resolve(s, sin)) {
RERROR("Unable to resolve %s", s);
return false;
}
sin->sin.sin_port = htons(atoi(x + 1));
return true;
}
static bool ParseSockaddrInWithoutPort(char *s, IpAddr *sin, DnsResolver *resolver) {
if (!resolver->Resolve(s, sin)) {
RERROR("Unable to resolve %s", s);
return false;
}
return true;
}
static bool ParseBase64Key(const char *s, uint8 key[32]) {
size_t size = 32;
return base64_decode((uint8*)s, strlen(s), key, &size) && size == 32;
}
class WgFileParser {
public:
WgFileParser(WireguardProcessor *wg, DnsResolver *resolver) : wg_(wg), dns_resolver_(resolver) {}
bool ParseFlag(const char *group, const char *key, char *value);
WireguardProcessor *wg_;
void FinishGroup();
struct Peer {
uint8 pub[32];
uint8 psk[32];
};
Peer pi_;
WgPeer *peer_ = NULL;
DnsResolver *dns_resolver_;
bool had_interface_ = false;
};
bool is_space(uint8_t c) {
return c == ' ' || c == '\r' || c == '\n' || c == '\t';
}
void SplitString(char *s, int separator, std::vector<char*> *components) {
for (;;) {
while (is_space(*s)) s++;
char *d = strchr(s, separator);
if (d == NULL) {
if (*s)
components->push_back(s);
return;
}
*d = 0;
char *e = d;
while (e > s && is_space(e[-1]))
*--e = 0;
components->push_back(s);
s = d + 1;
}
}
static bool ParseBoolean(const char *str, bool *value) {
if (_stricmp(str, "true") == 0 ||
_stricmp(str, "yes") == 0 ||
_stricmp(str, "1") == 0 ||
_stricmp(str, "on") == 0) {
*value = true;
return true;
}
if (_stricmp(str, "false") == 0 ||
_stricmp(str, "no") == 0 ||
_stricmp(str, "0") == 0 ||
_stricmp(str, "off") == 0) {
*value = false;
return true;
}
return false;
}
static int ParseFeature(const char *str) {
size_t len = strlen(str);
int what = WG_BOOLEAN_FEATURE_WANTS;
if (len > 0) {
if (str[len - 1] == '?')
what = WG_BOOLEAN_FEATURE_SUPPORTS, len--;
else if (str[len - 1] == '!')
what = WG_BOOLEAN_FEATURE_ENFORCES, len--;
}
if (len == 5 && memcmp(str, "mac64", 5) == 0)
return what + WG_FEATURE_ID_SHORT_MAC * 16;
if (len == 12 && memcmp(str, "short_header", 12) == 0)
return what + WG_FEATURE_ID_SHORT_HEADER * 16;
if (len == 5 && memcmp(str, "ipzip", 5) == 0)
return what + WG_FEATURE_ID_IPZIP * 16;
if (len == 10 && memcmp(str, "skip_keyid", 10) == 0)
return what + WG_FEATURE_ID_SKIP_KEYID_IN * 16 + 1 * 4;
if (len == 13 && memcmp(str, "skip_keyid_in", 13) == 0)
return what + WG_FEATURE_ID_SKIP_KEYID_IN * 16;
if (len == 14 && memcmp(str, "skip_keyid_out", 14) == 0)
return what + WG_FEATURE_ID_SKIP_KEYID_OUT * 16;
return -1;
}
static int ParseCipherSuite(const char *cipher) {
if (!strcmp(cipher, "chacha20-poly1305"))
return EXT_CIPHER_SUITE_CHACHA20POLY1305;
if (!strcmp(cipher, "aes128-gcm"))
return EXT_CIPHER_SUITE_AES128_GCM;
if (!strcmp(cipher, "aes256-gcm"))
return EXT_CIPHER_SUITE_AES256_GCM;
if (!strcmp(cipher, "none"))
return EXT_CIPHER_SUITE_NONE_POLY1305;
return -1;
}
void WgFileParser::FinishGroup() {
if (peer_) {
peer_->Initialize(pi_.pub, pi_.psk);
peer_ = NULL;
}
}
bool WgFileParser::ParseFlag(const char *group, const char *key, char *value) {
uint8 binkey[32];
WgCidrAddr addr;
IpAddr sin;
std::vector<char*> ss;
bool ciphermode = false;
if (strcmp(group, "[Interface]") == 0) {
if (key == NULL) return true;
if (strcmp(key, "PrivateKey") == 0) {
if (!ParseBase64Key(value, binkey))
return false;
had_interface_ = true;
wg_->dev().Initialize(binkey);
} else if (strcmp(key, "ListenPort") == 0) {
wg_->SetListenPort(atoi(value));
} else if (strcmp(key, "Address") == 0) {
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
if (!ParseCidrAddr(ss[i], &addr))
return false;
if (!wg_->SetTunAddress(addr)) {
RERROR("Multiple Address not allowed");
return false;
}
}
} else if (strcmp(key, "MTU") == 0) {
wg_->SetMtu(atoi(value));
} else if (strcmp(key, "Table") == 0) {
bool mode;
if (!strcmp(value, "off")) {
mode = false;
} else if (!strcmp(value, "auto")) {
mode = true;
} else {
goto err;
}
wg_->SetAddRoutesMode(mode);
} else if (strcmp(key, "DNS") == 0) {
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
if (!ParseSockaddrInWithoutPort(ss[i], &sin, dns_resolver_))
return false;
if (!wg_->AddDnsServer(sin)) {
RERROR("Multiple DNS not allowed.");
return false;
}
}
} else if (strcmp(key, "BlockDNS") == 0) {
bool v;
if (!ParseBoolean(value, &v))
goto err;
wg_->SetDnsBlocking(v);
} else if (strcmp(key, "BlockInternet") == 0) {
uint8 v = kBlockInternet_Default;
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
if (strcmp(ss[i], "route") == 0) {
if (v & 128) v = 0;
v |= kBlockInternet_Route;
} else if (strcmp(ss[i], "firewall") == 0) {
if (v & 128) v = 0;
v |= kBlockInternet_Firewall;
} else if (strcmp(ss[i], "off") == 0)
v = 0;
else if (strcmp(ss[i], "on") == 0)
v = kBlockInternet_DefaultOn;
else if (strcmp(ss[i], "default") == 0)
v = kBlockInternet_Default;
else
RERROR("Unknown mode in BlockInternet: %s", ss[i]);
}
wg_->SetInternetBlocking((InternetBlockState)v);
} else if (strcmp(key, "HeaderObfuscation") == 0) {
wg_->SetHeaderObfuscation(value);
} else if (strcmp(key, "PostUp") == 0) {
wg_->prepost().post_up.emplace_back(value);
} else if (strcmp(key, "PostDown") == 0) {
wg_->prepost().post_down.emplace_back(value);
} else if (strcmp(key, "PreUp") == 0) {
wg_->prepost().pre_up.emplace_back(value);
} else if (strcmp(key, "PreDown") == 0) {
wg_->prepost().pre_down.emplace_back(value);
} else if (strcmp(key, "ExcludedIPs") == 0) {
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
if (!ParseCidrAddr(ss[i], &addr))
return false;
wg_->AddExcludedIp(addr);
}
} else {
goto err;
}
} else if (strcmp(group, "[Peer]") == 0) {
if (key == NULL) {
if (!had_interface_) {
RERROR("Missing [Interface].PrivateKey.");
return false;
}
FinishGroup();
peer_ = wg_->dev().AddPeer();
memset(&pi_, 0, sizeof(pi_));
return true;
}
if (strcmp(key, "PublicKey") == 0) {
if (!ParseBase64Key(value, pi_.pub))
return false;
} else if (strcmp(key, "PresharedKey") == 0) {
if (!ParseBase64Key(value, pi_.psk))
return false;
} else if (strcmp(key, "AllowedIPs") == 0) {
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
if (!ParseCidrAddr(ss[i], &addr))
return false;
if (!peer_->AddIp(addr))
return false;
}
} else if (strcmp(key, "Endpoint") == 0) {
if (!ParseSockaddrInWithPort(value, &sin, dns_resolver_))
return false;
peer_->SetEndpoint(sin);
} else if (strcmp(key, "PersistentKeepalive") == 0) {
peer_->SetPersistentKeepalive(atoi(value));
} else if (strcmp(key, "AllowMulticast") == 0) {
bool b;
if (!ParseBoolean(value, &b))
return false;
peer_->SetAllowMulticast(b);
} else if (strcmp(key, "Features") == 0) {
SplitString(value, ',', &ss);
for (size_t i = 0; i < ss.size(); i++) {
int v = ParseFeature(ss[i]);
if (v < 0)
return false;
for (;; v += 12) {
peer_->SetFeature(v >> 4, v & 3);
if (!(v & 12))
break;
}
}
} else if (strcmp(key, "Ciphers") == 0 || (ciphermode = true, strcmp(key, "Ciphers!") == 0)) {
SplitString(value, ',', &ss);
peer_->SetCipherPrio(ciphermode);
for (size_t i = 0; i < ss.size(); i++) {
int v = ParseCipherSuite(ss[i]);
if (v < 0 || !peer_->AddCipher(v))
return false;
}
} else {
goto err;
}
} else {
err:
return false;
}
return true;
}
static bool ContainsNonAsciiCharacter(const char *buf, size_t size) {
for (size_t i = 0; i < size; i++) {
uint8 c = buf[i];
if (c < 32 && ((1 << c) & (1 << '\n' | 1 << '\r' | 1 << '\t')) == 0)
return true;
}
return false;
}
bool ParseWireGuardConfigFile(WireguardProcessor *wg, const char *filename, DnsResolver *dns_resolver) {
char buf[1024];
char group[32] = {0};
WgFileParser file_parser(wg, dns_resolver);
RINFO("Loading file: %s", filename);
FILE *f = fopen(filename, "r");
if (!f) {
RERROR("Unable to open: %s", filename);
return false;
}
while (fgets(buf, sizeof(buf), f)) {
size_t l = strlen(buf);
if (ContainsNonAsciiCharacter(buf, l)) {
RERROR("File is not a config file: %s", filename);
return false;
}
while (l && is_space(buf[l - 1]))
buf[--l] = 0;
if (buf[0] == '#' || buf[0] == '\0')
continue;
if (buf[0] == '[') {
size_t len = strlen(buf);
if (len < sizeof(group)) {
memcpy(group, buf, len + 1);
if (!file_parser.ParseFlag(group, NULL, NULL)) {
RERROR("Error parsing %s", group);
fclose(f);
return false;
}
}
continue;
}
char *sep = strchr(buf, '=');
if (!sep) {
RERROR("Missing = on line: %s", buf);
continue;
}
char *sepe = sep;
while (sepe > buf && is_space(sepe[-1]))
sepe--;
*sepe = 0;
// trim space after =
sep++;
while (is_space(*sep))
sep++;
if (!file_parser.ParseFlag(group, buf, sep)) {
RERROR("Error parsing %s.%s = %s", group, buf, sep);
fclose(f);
return false;
}
}
file_parser.FinishGroup();
fclose(f);
return true;
}