#include <bitcoin-build-config.h>
#include <netbase.h>
#include <compat/compat.h>
#include <logging.h>
#include <sync.h>
#include <tinyformat.h>
#include <util/sock.h>
#include <util/strencodings.h>
#include <util/string.h>
#include <util/time.h>
#include <atomic>
#include <chrono>
#include <cstdint>
#include <functional>
#include <limits>
#include <memory>

Include dependency graph for netbase.cpp:

Classes
class	TorStreamIsolationCredentialsGenerator
	Generate unique credentials for Tor stream isolation. More...

Enumerations
enum	SOCKSVersion : uint8_t { SOCKS4 = 0x04 , SOCKS5 = 0x05 }
	SOCKS version. More...

enum	SOCKS5Method : uint8_t { NOAUTH = 0x00 , GSSAPI = 0x01 , USER_PASS = 0x02 , NO_ACCEPTABLE = 0xff }
	Values defined for METHOD in RFC1928. More...

enum	SOCKS5Command : uint8_t { CONNECT = 0x01 , BIND = 0x02 , UDP_ASSOCIATE = 0x03 }
	Values defined for CMD in RFC1928. More...

enum	SOCKS5Reply : uint8_t { SUCCEEDED = 0x00 , GENFAILURE = 0x01 , NOTALLOWED = 0x02 , NETUNREACHABLE = 0x03 , HOSTUNREACHABLE = 0x04 , CONNREFUSED = 0x05 , TTLEXPIRED = 0x06 , CMDUNSUPPORTED = 0x07 , ATYPEUNSUPPORTED = 0x08 , TOR_HS_DESC_NOT_FOUND = 0xf0 , TOR_HS_DESC_INVALID = 0xf1 , TOR_HS_INTRO_FAILED = 0xf2 , TOR_HS_REND_FAILED = 0xf3 , TOR_HS_MISSING_CLIENT_AUTH = 0xf4 , TOR_HS_WRONG_CLIENT_AUTH = 0xf5 , TOR_HS_BAD_ADDRESS = 0xf6 , TOR_HS_INTRO_TIMEOUT = 0xf7 }
	Values defined for REP in RFC1928 and https://spec.torproject.org/socks-extensions.html. More...

enum	SOCKS5Atyp : uint8_t { IPV4 = 0x01 , DOMAINNAME = 0x03 , IPV6 = 0x04 }
	Values defined for ATYPE in RFC1928. More...

enum class	IntrRecvError { OK , Timeout , Disconnected , NetworkError , Interrupted }
	Status codes that can be returned by InterruptibleRecv. More...

Functions
static Proxy proxyInfo[NET_MAX]	GUARDED_BY (g_proxyinfo_mutex)

std::vector< CNetAddr >	WrappedGetAddrInfo (const std::string &name, bool allow_lookup)
	Wrapper for getaddrinfo(3). More...

enum Network	ParseNetwork (const std::string &net_in)

std::string	GetNetworkName (enum Network net)

std::vector< std::string >	GetNetworkNames (bool append_unroutable)
	Return a vector of publicly routable Network names; optionally append NET_UNROUTABLE. More...

static std::vector< CNetAddr >	LookupIntern (const std::string &name, unsigned int nMaxSolutions, bool fAllowLookup, DNSLookupFn dns_lookup_function)

std::vector< CNetAddr >	LookupHost (const std::string &name, unsigned int nMaxSolutions, bool fAllowLookup, DNSLookupFn dns_lookup_function)
	Resolve a host string to its corresponding network addresses. More...

std::optional< CNetAddr >	LookupHost (const std::string &name, bool fAllowLookup, DNSLookupFn dns_lookup_function)
	Resolve a host string to its first corresponding network address. More...

std::vector< CService >	Lookup (const std::string &name, uint16_t portDefault, bool fAllowLookup, unsigned int nMaxSolutions, DNSLookupFn dns_lookup_function)
	Resolve a service string to its corresponding service. More...

std::optional< CService >	Lookup (const std::string &name, uint16_t portDefault, bool fAllowLookup, DNSLookupFn dns_lookup_function)
	Resolve a service string to its first corresponding service. More...

CService	LookupNumeric (const std::string &name, uint16_t portDefault, DNSLookupFn dns_lookup_function)
	Resolve a service string with a numeric IP to its first corresponding service. More...

bool	IsUnixSocketPath (const std::string &name)
	Check if a string is a valid UNIX domain socket path. More...

static IntrRecvError	InterruptibleRecv (uint8_t *data, size_t len, std::chrono::milliseconds timeout, const Sock &sock)
	Try to read a specified number of bytes from a socket. More...

static std::string	Socks5ErrorString (uint8_t err)
	Convert SOCKS5 reply to an error message. More...

bool	Socks5 (const std::string &strDest, uint16_t port, const ProxyCredentials *auth, const Sock &sock)
	Connect to a specified destination service through an already connected SOCKS5 proxy. More...

std::unique_ptr< Sock >	CreateSockOS (int domain, int type, int protocol)
	Create a real socket from the operating system. More...

template<typename... Args>
static void	LogConnectFailure (bool manual_connection, util::ConstevalFormatString< sizeof...(Args)> fmt, const Args &... args)

static bool	ConnectToSocket (const Sock &sock, struct sockaddr *sockaddr, socklen_t len, const std::string &dest_str, bool manual_connection)

std::unique_ptr< Sock >	ConnectDirectly (const CService &dest, bool manual_connection)
	Create a socket and try to connect to the specified service. More...

bool	SetProxy (enum Network net, const Proxy &addrProxy)

bool	GetProxy (enum Network net, Proxy &proxyInfoOut)

bool	SetNameProxy (const Proxy &addrProxy)
	Set the name proxy to use for all connections to nodes specified by a hostname. More...

bool	GetNameProxy (Proxy &nameProxyOut)

bool	HaveNameProxy ()

bool	IsProxy (const CNetAddr &addr)

std::unique_ptr< Sock >	ConnectThroughProxy (const Proxy &proxy, const std::string &dest, uint16_t port, bool &proxy_connection_failed)
	Connect to a specified destination service through a SOCKS5 proxy by first connecting to the SOCKS5 proxy. More...

CSubNet	LookupSubNet (const std::string &subnet_str)
	Parse and resolve a specified subnet string into the appropriate internal representation. More...

bool	IsBadPort (uint16_t port)
	Determine if a port is "bad" from the perspective of attempting to connect to a node on that port. More...

CService	MaybeFlipIPv6toCJDNS (const CService &service)
	If an IPv6 address belongs to the address range used by the CJDNS network and the CJDNS network is reachable (-cjdnsreachable config is set), then change the type from NET_IPV6 to NET_CJDNS. More...

Variables
static GlobalMutex	g_proxyinfo_mutex

int	nConnectTimeout = DEFAULT_CONNECT_TIMEOUT

bool	fNameLookup = DEFAULT_NAME_LOOKUP

std::chrono::milliseconds	g_socks5_recv_timeout = 20s

CThreadInterrupt	g_socks5_interrupt
	Interrupt SOCKS5 reads or writes. More...

ReachableNets	g_reachable_nets

DNSLookupFn	g_dns_lookup {WrappedGetAddrInfo}

std::function< std::unique_ptr< Sock >(int, int, int)>	CreateSock = CreateSockOS
	Socket factory. More...

Enumeration Type Documentation

◆ IntrRecvError

enum class IntrRecvError

strong

Status codes that can be returned by InterruptibleRecv.

Enumerator
OK
Timeout
Disconnected
NetworkError
Interrupted

Definition at line 298 of file netbase.cpp.

◆ SOCKS5Atyp

enum SOCKS5Atyp : uint8_t

Values defined for ATYPE in RFC1928.

Enumerator
IPV4
DOMAINNAME
IPV6

Definition at line 291 of file netbase.cpp.

◆ SOCKS5Command

enum SOCKS5Command : uint8_t

Values defined for CMD in RFC1928.

Enumerator
CONNECT
BIND
UDP_ASSOCIATE

Definition at line 263 of file netbase.cpp.

◆ SOCKS5Method

enum SOCKS5Method : uint8_t

Values defined for METHOD in RFC1928.

Enumerator
NOAUTH	No authentication required.
GSSAPI	GSSAPI.
USER_PASS	Username/password.
NO_ACCEPTABLE	No acceptable methods.

Definition at line 255 of file netbase.cpp.

◆ SOCKS5Reply

enum SOCKS5Reply : uint8_t

Values defined for REP in RFC1928 and https://spec.torproject.org/socks-extensions.html.

Enumerator
SUCCEEDED	RFC1928: Succeeded.
GENFAILURE	RFC1928: General failure.
NOTALLOWED	RFC1928: Connection not allowed by ruleset.
NETUNREACHABLE	RFC1928: Network unreachable.
HOSTUNREACHABLE	RFC1928: Network unreachable.
CONNREFUSED	RFC1928: Connection refused.
TTLEXPIRED	RFC1928: TTL expired.
CMDUNSUPPORTED	RFC1928: Command not supported.
ATYPEUNSUPPORTED	RFC1928: Address type not supported.
TOR_HS_DESC_NOT_FOUND	Tor: Onion service descriptor can not be found.
TOR_HS_DESC_INVALID	Tor: Onion service descriptor is invalid.
TOR_HS_INTRO_FAILED	Tor: Onion service introduction failed.
TOR_HS_REND_FAILED	Tor: Onion service rendezvous failed.
TOR_HS_MISSING_CLIENT_AUTH	Tor: Onion service missing client authorization.
TOR_HS_WRONG_CLIENT_AUTH	Tor: Onion service wrong client authorization.
TOR_HS_BAD_ADDRESS	Tor: Onion service invalid address.
TOR_HS_INTRO_TIMEOUT	Tor: Onion service introduction timed out.

Definition at line 270 of file netbase.cpp.

◆ SOCKSVersion

enum SOCKSVersion : uint8_t

SOCKS version.

Enumerator
SOCKS4
SOCKS5

Definition at line 249 of file netbase.cpp.

Function Documentation

◆ ConnectDirectly()

std::unique_ptr< Sock > ConnectDirectly	(	const CService &	dest,
		bool	manual_connection
	)

Create a socket and try to connect to the specified service.

Parameters

[in]	dest	The service to which to connect.
[in]	manual_connection	Whether or not the connection was manually requested (e.g. through the addnode RPC)

Returns: the connected socket if the operation succeeded, empty unique_ptr otherwise

Definition at line 649 of file netbase.cpp.

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◆ ConnectThroughProxy()

std::unique_ptr< Sock > ConnectThroughProxy	(	const Proxy &	proxy,
		const std::string &	dest,
		uint16_t	port,
		bool &	proxy_connection_failed
	)

Connect to a specified destination service through a SOCKS5 proxy by first connecting to the SOCKS5 proxy.

Parameters

[in]	proxy	The SOCKS5 proxy.
[in]	dest	The destination service to which to connect.
[in]	port	The destination port.
[out]	proxy_connection_failed	Whether or not the connection to the SOCKS5 proxy failed.

Returns: the connected socket if the operation succeeded. Otherwise an empty unique_ptr.

Definition at line 789 of file netbase.cpp.

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◆ ConnectToSocket()

static bool ConnectToSocket	(	const Sock &	sock,
		struct sockaddr *	sockaddr,
		socklen_t	len,
		const std::string &	dest_str,
		bool	manual_connection
	)

static

Definition at line 594 of file netbase.cpp.

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◆ CreateSockOS()

std::unique_ptr< Sock > CreateSockOS	(	int	domain,
		int	type,
		int	protocol
	)

Create a real socket from the operating system.

Parameters

[in]	domain	Communications domain, first argument to the socket(2) syscall.
[in]	type	Type of the socket, second argument to the socket(2) syscall.
[in]	protocol	The particular protocol to be used with the socket, third argument to the socket(2) syscall.

Returns: pointer to the created Sock object or unique_ptr that owns nothing in case of failure

Definition at line 526 of file netbase.cpp.

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◆ GetNameProxy()

bool GetNameProxy ( Proxy & nameProxyOut )

Definition at line 730 of file netbase.cpp.

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◆ GetNetworkName()

std::string GetNetworkName ( enum Network net )

Definition at line 118 of file netbase.cpp.

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◆ GetNetworkNames()

std::vector< std::string > GetNetworkNames ( bool append_unroutable )

Return a vector of publicly routable Network names; optionally append NET_UNROUTABLE.

Definition at line 134 of file netbase.cpp.

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◆ GetProxy()

bool GetProxy	(	enum Network	net,
		Proxy &	proxyInfoOut
	)

Definition at line 713 of file netbase.cpp.

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◆ GUARDED_BY()

static Proxy nameProxy GUARDED_BY ( g_proxyinfo_mutex )

static

◆ HaveNameProxy()

bool HaveNameProxy ( )

Definition at line 738 of file netbase.cpp.

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◆ InterruptibleRecv()

static IntrRecvError InterruptibleRecv	(	uint8_t *	data,
		size_t	len,
		std::chrono::milliseconds	timeout,
		const Sock &	sock
	)

static

Try to read a specified number of bytes from a socket.

Please read the "see also" section for more detail.

Parameters

data	The buffer where the read bytes should be stored.
len	The number of bytes to read into the specified buffer.
timeout	The total timeout for this read.
sock	The socket (has to be in non-blocking mode) from which to read bytes.

Returns: An IntrRecvError indicating the resulting status of this read. IntrRecvError::OK only if all of the specified number of bytes were read.

See also: This function can be interrupted by calling g_socks5_interrupt(). Sockets can be made non-blocking with Sock::SetNonBlocking().

Definition at line 322 of file netbase.cpp.

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◆ IsBadPort()

bool IsBadPort ( uint16_t port )

Determine if a port is "bad" from the perspective of attempting to connect to a node on that port.

See also: doc/p2p-bad-ports.md

Parameters

[in] port Port to check.

Returns: whether the port is bad

Definition at line 851 of file netbase.cpp.

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◆ IsProxy()

bool IsProxy ( const CNetAddr & addr )

Definition at line 743 of file netbase.cpp.

◆ IsUnixSocketPath()

bool IsUnixSocketPath ( const std::string & name )

Check if a string is a valid UNIX domain socket path.

Parameters

name	The string provided by the user representing a local path

Returns: Whether the string has proper format, length, and points to an existing file path

Definition at line 230 of file netbase.cpp.

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◆ LogConnectFailure()

template<typename... Args>

static void LogConnectFailure	(	bool	manual_connection,
		util::ConstevalFormatString< sizeof...(Args)>	fmt,
		const Args &...	args
	)

static

Definition at line 584 of file netbase.cpp.

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◆ Lookup() [1/2]

std::optional< CService > Lookup	(	const std::string &	name,
		uint16_t	portDefault,
		bool	fAllowLookup,
		DNSLookupFn	dns_lookup_function = `g_dns_lookup`
	)

Resolve a service string to its first corresponding service.

See also: Lookup(const std::string&, uint16_t, bool, unsigned int, DNSLookupFn) for additional parameter descriptions.

Definition at line 213 of file netbase.cpp.

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◆ Lookup() [2/2]

std::vector< CService > Lookup	(	const std::string &	name,
		uint16_t	portDefault,
		bool	fAllowLookup,
		unsigned int	nMaxSolutions,
		DNSLookupFn	dns_lookup_function = `g_dns_lookup`
	)

Resolve a service string to its corresponding service.

Parameters

name	The string representing a service. Could be a name or a numerical IP address (IPv6 addresses should be in their disambiguated bracketed form), optionally followed by a uint16_t port number. (e.g. example.com:8333 or
portDefault	The default port for resulting services if not specified by the service string.
fAllowLookup	Whether or not hostname lookups are permitted. If yes, external queries may be performed.
nMaxSolutions	The maximum number of results we want, specifying 0 means "as many solutions as we get."

Returns: The resulting services to which the specified service string resolved.

Definition at line 195 of file netbase.cpp.

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◆ LookupHost() [1/2]

std::optional< CNetAddr > LookupHost	(	const std::string &	name,
		bool	fAllowLookup,
		DNSLookupFn	dns_lookup_function = `g_dns_lookup`
	)

Resolve a host string to its first corresponding network address.

Returns: The resulting network address to which the specified host string resolved or std::nullopt if host does not resolve to an address.

See also: LookupHost(const std::string&, unsigned int, bool, DNSLookupFn) for additional parameter descriptions.

Definition at line 189 of file netbase.cpp.

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◆ LookupHost() [2/2]

std::vector< CNetAddr > LookupHost	(	const std::string &	name,
		unsigned int	nMaxSolutions,
		bool	fAllowLookup,
		DNSLookupFn	dns_lookup_function = `g_dns_lookup`
	)

Resolve a host string to its corresponding network addresses.

Parameters

name	The string representing a host. Could be a name or a numerical IP address (IPv6 addresses in their bracketed form are allowed).

Returns: The resulting network addresses to which the specified host string resolved.

See also: Lookup(const std::string&, uint16_t, bool, unsigned int, DNSLookupFn) for additional parameter descriptions.

Definition at line 177 of file netbase.cpp.

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◆ LookupIntern()

static std::vector< CNetAddr > LookupIntern	(	const std::string &	name,
		unsigned int	nMaxSolutions,
		bool	fAllowLookup,
		DNSLookupFn	dns_lookup_function
	)

static

Definition at line 148 of file netbase.cpp.

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◆ LookupNumeric()

CService LookupNumeric	(	const std::string &	name,
		uint16_t	portDefault = `0`,
		DNSLookupFn	dns_lookup_function = `g_dns_lookup`
	)

Resolve a service string with a numeric IP to its first corresponding service.

Returns: The resulting CService if the resolution was successful, [::]:0 otherwise.

See also: Lookup(const std::string&, uint16_t, bool, unsigned int, DNSLookupFn) for additional parameter descriptions.

Definition at line 220 of file netbase.cpp.

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◆ LookupSubNet()

CSubNet LookupSubNet ( const std::string & subnet_str )

Parse and resolve a specified subnet string into the appropriate internal representation.

Parameters

[in] subnet_str A string representation of a subnet of the form network address [ "/", ( CIDR-style suffix | netmask ) ] e.g. "2001:db8::/32", "192.0.2.0/255.255.255.0" or "8.8.8.8".

Returns: a CSubNet object (that may or may not be valid).

Definition at line 816 of file netbase.cpp.

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◆ MaybeFlipIPv6toCJDNS()

CService MaybeFlipIPv6toCJDNS ( const CService & service )

If an IPv6 address belongs to the address range used by the CJDNS network and the CJDNS network is reachable (-cjdnsreachable config is set), then change the type from NET_IPV6 to NET_CJDNS.

Parameters

[in] service Address to potentially convert.

Returns: a copy of service either unmodified or changed to CJDNS.

Definition at line 941 of file netbase.cpp.

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◆ ParseNetwork()

enum Network ParseNetwork ( const std::string & net_in )

Definition at line 100 of file netbase.cpp.

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◆ SetNameProxy()

bool SetNameProxy ( const Proxy & addrProxy )

Set the name proxy to use for all connections to nodes specified by a hostname.

After setting this proxy, connecting to a node specified by a hostname won't result in a local lookup of said hostname, rather, connect to the node by asking the name proxy for a proxy connection to the hostname, effectively delegating the hostname lookup to the specified proxy.

This delegation increases privacy for those who set the name proxy as they no longer leak their external hostname queries to their DNS servers.

Returns: Whether or not the operation succeeded.

Note: SOCKS5's support for UDP-over-SOCKS5 has been considered, but no SOCK5 server in common use (most notably Tor) actually implements UDP support, and a DNS resolver is beyond the scope of this project.

Definition at line 722 of file netbase.cpp.

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◆ SetProxy()

bool SetProxy	(	enum Network	net,
		const Proxy &	addrProxy
	)

Definition at line 704 of file netbase.cpp.

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◆ Socks5()

bool Socks5	(	const std::string &	strDest,
		uint16_t	port,
		const ProxyCredentials *	auth,
		const Sock &	socket
	)

Connect to a specified destination service through an already connected SOCKS5 proxy.

Parameters

strDest	The destination fully-qualified domain name.
port	The destination port.
auth	The credentials with which to authenticate with the specified SOCKS5 proxy.
socket	The SOCKS5 proxy socket.

Returns: Whether or not the operation succeeded.

Note: The specified SOCKS5 proxy socket must already be connected to the SOCKS5 proxy.

See also: RFC1928: SOCKS Protocol Version 5

Definition at line 396 of file netbase.cpp.

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◆ Socks5ErrorString()

static std::string Socks5ErrorString ( uint8_t err )

static

Convert SOCKS5 reply to an error message.

Definition at line 356 of file netbase.cpp.

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◆ WrappedGetAddrInfo()

std::vector< CNetAddr > WrappedGetAddrInfo	(	const std::string &	name,
		bool	allow_lookup
	)

Wrapper for getaddrinfo(3).

Do not use directly: call Lookup/LookupHost/LookupNumeric/LookupSubNet.

Definition at line 45 of file netbase.cpp.

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Variable Documentation

◆ CreateSock

std::function<std::unique_ptr<Sock>(int, int, int)> CreateSock = CreateSockOS

Socket factory.

Defaults to CreateSockOS(), but can be overridden by unit tests.

Definition at line 581 of file netbase.cpp.

◆ fNameLookup

bool fNameLookup = DEFAULT_NAME_LOOKUP

Definition at line 37 of file netbase.cpp.

◆ g_dns_lookup

DNSLookupFn g_dns_lookup {WrappedGetAddrInfo}

Definition at line 98 of file netbase.cpp.

◆ g_proxyinfo_mutex

GlobalMutex g_proxyinfo_mutex

static

Definition at line 33 of file netbase.cpp.

◆ g_reachable_nets

ReachableNets g_reachable_nets

Definition at line 43 of file netbase.cpp.

◆ g_socks5_interrupt

CThreadInterrupt g_socks5_interrupt

Interrupt SOCKS5 reads or writes.

Definition at line 41 of file netbase.cpp.

◆ g_socks5_recv_timeout

std::chrono::milliseconds g_socks5_recv_timeout = 20s

Definition at line 40 of file netbase.cpp.

◆ nConnectTimeout

int nConnectTimeout = DEFAULT_CONNECT_TIMEOUT

Definition at line 36 of file netbase.cpp.

Classes

Enumerations

Functions

Variables

Enumeration Type Documentation

◆ IntrRecvError

◆ SOCKS5Atyp

◆ SOCKS5Command

◆ SOCKS5Method

◆ SOCKS5Reply

◆ SOCKSVersion

Function Documentation

◆ ConnectDirectly()

◆ ConnectThroughProxy()

◆ ConnectToSocket()

◆ CreateSockOS()

◆ GetNameProxy()

◆ GetNetworkName()

◆ GetNetworkNames()

◆ GetProxy()

◆ GUARDED_BY()

◆ HaveNameProxy()

◆ InterruptibleRecv()

◆ IsBadPort()

◆ IsProxy()

◆ IsUnixSocketPath()

◆ LogConnectFailure()

◆ Lookup() [1/2]

◆ Lookup() [2/2]

◆ LookupHost() [1/2]

◆ LookupHost() [2/2]

◆ LookupIntern()

◆ LookupNumeric()

◆ LookupSubNet()

◆ MaybeFlipIPv6toCJDNS()

◆ ParseNetwork()

◆ SetNameProxy()

◆ SetProxy()

◆ Socks5()

◆ Socks5ErrorString()

◆ WrappedGetAddrInfo()

Variable Documentation

◆ CreateSock

◆ fNameLookup

◆ g_dns_lookup

◆ g_proxyinfo_mutex

◆ g_reachable_nets

◆ g_socks5_interrupt

◆ g_socks5_recv_timeout

◆ nConnectTimeout