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Diffstat (limited to 'lib/pure/rawsockets.nim')
| -rw-r--r-- | lib/pure/rawsockets.nim | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/lib/pure/rawsockets.nim b/lib/pure/rawsockets.nim new file mode 100644 index 000000000..aeaa7f3b5 --- /dev/null +++ b/lib/pure/rawsockets.nim @@ -0,0 +1,421 @@ +# +# +# Nimrod's Runtime Library +# (c) Copyright 2014 Dominik Picheta +# +# See the file "copying.txt", included in this +# distribution, for details about the copyright. +# + +## This module implements a low-level cross-platform sockets interface. Look +## at the ``net`` module for the higher-level version. + +# TODO: Clean up the exports a bit and everything else in general. + +import unsigned, os + +when hostos == "solaris": + {.passl: "-lsocket -lnsl".} + +when defined(Windows): + import winlean + export WSAEWOULDBLOCK +else: + import posix + export fcntl, F_GETFL, O_NONBLOCK, F_SETFL, EAGAIN, EWOULDBLOCK, MSG_NOSIGNAL, + EINTR, EINPROGRESS + +export TSocketHandle, TSockaddr_in, TAddrinfo, INADDR_ANY, TSockAddr, TSockLen, + inet_ntoa, recv, `==`, connect, send, accept, recvfrom, sendto + +export + SO_ERROR, + SOL_SOCKET, + SOMAXCONN, + SO_ACCEPTCONN, SO_BROADCAST, SO_DEBUG, SO_DONTROUTE, + SO_KEEPALIVE, SO_OOBINLINE, SO_REUSEADDR, + MSG_PEEK + +type + + TPort* = distinct uint16 ## port type + + TDomain* = enum ## domain, which specifies the protocol family of the + ## created socket. Other domains than those that are listed + ## here are unsupported. + AF_UNIX, ## for local socket (using a file). Unsupported on Windows. + AF_INET = 2, ## for network protocol IPv4 or + AF_INET6 = 23 ## for network protocol IPv6. + + TType* = enum ## second argument to `socket` proc + SOCK_STREAM = 1, ## reliable stream-oriented service or Stream Sockets + SOCK_DGRAM = 2, ## datagram service or Datagram Sockets + SOCK_RAW = 3, ## raw protocols atop the network layer. + SOCK_SEQPACKET = 5 ## reliable sequenced packet service + + TProtocol* = enum ## third argument to `socket` proc + IPPROTO_TCP = 6, ## Transmission control protocol. + IPPROTO_UDP = 17, ## User datagram protocol. + IPPROTO_IP, ## Internet protocol. Unsupported on Windows. + IPPROTO_IPV6, ## Internet Protocol Version 6. Unsupported on Windows. + IPPROTO_RAW, ## Raw IP Packets Protocol. Unsupported on Windows. + IPPROTO_ICMP ## Control message protocol. Unsupported on Windows. + + TServent* {.pure, final.} = object ## information about a service + name*: string + aliases*: seq[string] + port*: TPort + proto*: string + + Thostent* {.pure, final.} = object ## information about a given host + name*: string + aliases*: seq[string] + addrtype*: TDomain + length*: int + addrList*: seq[string] + +when defined(windows): + let + osInvalidSocket* = winlean.INVALID_SOCKET + + const + IOCPARM_MASK* = 127 + IOC_IN* = int(-2147483648) + FIONBIO* = IOC_IN.int32 or ((sizeof(int32) and IOCPARM_MASK) shl 16) or + (102 shl 8) or 126 + + proc ioctlsocket*(s: TSocketHandle, cmd: clong, + argptr: ptr clong): cint {. + stdcall, importc: "ioctlsocket", dynlib: "ws2_32.dll".} +else: + let + osInvalidSocket* = posix.INVALID_SOCKET + +proc `==`*(a, b: TPort): bool {.borrow.} + ## ``==`` for ports. + +proc `$`*(p: TPort): string {.borrow.} + ## returns the port number as a string + +proc toInt*(domain: TDomain): cint + ## Converts the TDomain enum to a platform-dependent ``cint``. + +proc toInt*(typ: TType): cint + ## Converts the TType enum to a platform-dependent ``cint``. + +proc toInt*(p: TProtocol): cint + ## Converts the TProtocol enum to a platform-dependent ``cint``. + +when defined(posix): + proc toInt(domain: TDomain): cint = + case domain + of AF_UNIX: result = posix.AF_UNIX + of AF_INET: result = posix.AF_INET + of AF_INET6: result = posix.AF_INET6 + else: discard + + proc toInt(typ: TType): cint = + case typ + of SOCK_STREAM: result = posix.SOCK_STREAM + of SOCK_DGRAM: result = posix.SOCK_DGRAM + of SOCK_SEQPACKET: result = posix.SOCK_SEQPACKET + of SOCK_RAW: result = posix.SOCK_RAW + else: discard + + proc toInt(p: TProtocol): cint = + case p + of IPPROTO_TCP: result = posix.IPPROTO_TCP + of IPPROTO_UDP: result = posix.IPPROTO_UDP + of IPPROTO_IP: result = posix.IPPROTO_IP + of IPPROTO_IPV6: result = posix.IPPROTO_IPV6 + of IPPROTO_RAW: result = posix.IPPROTO_RAW + of IPPROTO_ICMP: result = posix.IPPROTO_ICMP + else: discard + +else: + proc toInt(domain: TDomain): cint = + result = toU16(ord(domain)) + + proc toInt(typ: TType): cint = + result = cint(ord(typ)) + + proc toInt(p: TProtocol): cint = + result = cint(ord(p)) + + +proc newRawSocket*(domain: TDomain = AF_INET, typ: TType = SOCK_STREAM, + protocol: TProtocol = IPPROTO_TCP): TSocketHandle = + ## Creates a new socket; returns `InvalidSocket` if an error occurs. + socket(toInt(domain), toInt(typ), toInt(protocol)) + +proc close*(socket: TSocketHandle) = + ## closes a socket. + when defined(windows): + discard winlean.closeSocket(socket) + else: + discard posix.close(socket) + # TODO: These values should not be discarded. An EOS should be raised. + # http://stackoverflow.com/questions/12463473/what-happens-if-you-call-close-on-a-bsd-socket-multiple-times + +proc bindAddr*(socket: TSocketHandle, name: ptr TSockAddr, namelen: TSockLen): cint = + result = bindSocket(socket, name, namelen) + +proc listen*(socket: TSocketHandle, backlog = SOMAXCONN): cint {.tags: [FReadIO].} = + ## Marks ``socket`` as accepting connections. + ## ``Backlog`` specifies the maximum length of the + ## queue of pending connections. + when defined(windows): + result = winlean.listen(socket, cint(backlog)) + else: + result = posix.listen(socket, cint(backlog)) + +proc getAddrInfo*(address: string, port: TPort, af: TDomain = AF_INET, typ: TType = SOCK_STREAM, + prot: TProtocol = IPPROTO_TCP): ptr TAddrInfo = + ## + ## + ## **Warning**: The resulting ``ptr TAddrInfo`` must be freed using ``dealloc``! + var hints: TAddrInfo + result = nil + hints.ai_family = toInt(af) + hints.ai_socktype = toInt(typ) + hints.ai_protocol = toInt(prot) + var gaiResult = getAddrInfo(address, $port, addr(hints), result) + if gaiResult != 0'i32: + when defined(windows): + OSError(OSLastError()) + else: + raise newException(EOS, $gai_strerror(gaiResult)) + +proc dealloc*(ai: ptr TAddrInfo) = + freeaddrinfo(ai) + +proc ntohl*(x: int32): int32 = + ## Converts 32-bit integers from network to host byte order. + ## On machines where the host byte order is the same as network byte order, + ## this is a no-op; otherwise, it performs a 4-byte swap operation. + when cpuEndian == bigEndian: result = x + else: result = (x shr 24'i32) or + (x shr 8'i32 and 0xff00'i32) or + (x shl 8'i32 and 0xff0000'i32) or + (x shl 24'i32) + +proc ntohs*(x: int16): int16 = + ## Converts 16-bit integers from network to host byte order. On machines + ## where the host byte order is the same as network byte order, this is + ## a no-op; otherwise, it performs a 2-byte swap operation. + when cpuEndian == bigEndian: result = x + else: result = (x shr 8'i16) or (x shl 8'i16) + +proc htonl*(x: int32): int32 = + ## Converts 32-bit integers from host to network byte order. On machines + ## where the host byte order is the same as network byte order, this is + ## a no-op; otherwise, it performs a 4-byte swap operation. + result = rawsockets.ntohl(x) + +proc htons*(x: int16): int16 = + ## Converts 16-bit positive integers from host to network byte order. + ## On machines where the host byte order is the same as network byte + ## order, this is a no-op; otherwise, it performs a 2-byte swap operation. + result = rawsockets.ntohs(x) + +proc getServByName*(name, proto: string): TServent {.tags: [FReadIO].} = + ## Searches the database from the beginning and finds the first entry for + ## which the service name specified by ``name`` matches the s_name member + ## and the protocol name specified by ``proto`` matches the s_proto member. + ## + ## On posix this will search through the ``/etc/services`` file. + when defined(Windows): + var s = winlean.getservbyname(name, proto) + else: + var s = posix.getservbyname(name, proto) + if s == nil: raise newException(EOS, "Service not found.") + result.name = $s.s_name + result.aliases = cstringArrayToSeq(s.s_aliases) + result.port = TPort(s.s_port) + result.proto = $s.s_proto + +proc getServByPort*(port: TPort, proto: string): TServent {.tags: [FReadIO].} = + ## Searches the database from the beginning and finds the first entry for + ## which the port specified by ``port`` matches the s_port member and the + ## protocol name specified by ``proto`` matches the s_proto member. + ## + ## On posix this will search through the ``/etc/services`` file. + when defined(Windows): + var s = winlean.getservbyport(ze(int16(port)).cint, proto) + else: + var s = posix.getservbyport(ze(int16(port)).cint, proto) + if s == nil: raise newException(EOS, "Service not found.") + result.name = $s.s_name + result.aliases = cstringArrayToSeq(s.s_aliases) + result.port = TPort(s.s_port) + result.proto = $s.s_proto + +proc getHostByAddr*(ip: string): Thostent {.tags: [FReadIO].} = + ## This function will lookup the hostname of an IP Address. + var myaddr: TInAddr + myaddr.s_addr = inet_addr(ip) + + when defined(windows): + var s = winlean.gethostbyaddr(addr(myaddr), sizeof(myaddr).cuint, + cint(rawsockets.AF_INET)) + if s == nil: osError(osLastError()) + else: + var s = posix.gethostbyaddr(addr(myaddr), sizeof(myaddr).TSocklen, + cint(posix.AF_INET)) + if s == nil: + raise newException(EOS, $hstrerror(h_errno)) + + result.name = $s.h_name + result.aliases = cstringArrayToSeq(s.h_aliases) + when defined(windows): + result.addrtype = TDomain(s.h_addrtype) + else: + if s.h_addrtype == posix.AF_INET: + result.addrtype = AF_INET + elif s.h_addrtype == posix.AF_INET6: + result.addrtype = AF_INET6 + else: + raise newException(EOS, "unknown h_addrtype") + result.addrList = cstringArrayToSeq(s.h_addr_list) + result.length = int(s.h_length) + +proc getHostByName*(name: string): Thostent {.tags: [FReadIO].} = + ## This function will lookup the IP address of a hostname. + when defined(Windows): + var s = winlean.gethostbyname(name) + else: + var s = posix.gethostbyname(name) + if s == nil: osError(osLastError()) + result.name = $s.h_name + result.aliases = cstringArrayToSeq(s.h_aliases) + when defined(windows): + result.addrtype = TDomain(s.h_addrtype) + else: + if s.h_addrtype == posix.AF_INET: + result.addrtype = AF_INET + elif s.h_addrtype == posix.AF_INET6: + result.addrtype = AF_INET6 + else: + raise newException(EOS, "unknown h_addrtype") + result.addrList = cstringArrayToSeq(s.h_addr_list) + result.length = int(s.h_length) + +proc getSockName*(socket: TSocketHandle): TPort = + ## returns the socket's associated port number. + var name: Tsockaddr_in + when defined(Windows): + name.sin_family = int16(ord(AF_INET)) + else: + name.sin_family = posix.AF_INET + #name.sin_port = htons(cint16(port)) + #name.sin_addr.s_addr = htonl(INADDR_ANY) + var namelen = sizeof(name).TSocklen + if getsockname(socket, cast[ptr TSockAddr](addr(name)), + addr(namelen)) == -1'i32: + osError(osLastError()) + result = TPort(rawsockets.ntohs(name.sin_port)) + +proc getSockOptInt*(socket: TSocketHandle, level, optname: int): int {. + tags: [FReadIO].} = + ## getsockopt for integer options. + var res: cint + var size = sizeof(res).TSocklen + if getsockopt(socket, cint(level), cint(optname), + addr(res), addr(size)) < 0'i32: + osError(osLastError()) + result = int(res) + +proc setSockOptInt*(socket: TSocketHandle, level, optname, optval: int) {. + tags: [FWriteIO].} = + ## setsockopt for integer options. + var value = cint(optval) + if setsockopt(socket, cint(level), cint(optname), addr(value), + sizeof(value).TSocklen) < 0'i32: + osError(osLastError()) + +proc setBlocking*(s: TSocketHandle, blocking: bool) = + ## Sets blocking mode on socket. + ## + ## Raises EOS on error. + when defined(Windows): + var mode = clong(ord(not blocking)) # 1 for non-blocking, 0 for blocking + if ioctlsocket(s, FIONBIO, addr(mode)) == -1: + osError(osLastError()) + else: # BSD sockets + var x: int = fcntl(s, F_GETFL, 0) + if x == -1: + osError(osLastError()) + else: + var mode = if blocking: x and not O_NONBLOCK else: x or O_NONBLOCK + if fcntl(s, F_SETFL, mode) == -1: + osError(osLastError()) + +proc timeValFromMilliseconds(timeout = 500): Ttimeval = + if timeout != -1: + var seconds = timeout div 1000 + result.tv_sec = seconds.int32 + result.tv_usec = ((timeout - seconds * 1000) * 1000).int32 + +proc createFdSet(fd: var TFdSet, s: seq[TSocketHandle], m: var int) = + FD_ZERO(fd) + for i in items(s): + m = max(m, int(i)) + FD_SET(i, fd) + +proc pruneSocketSet(s: var seq[TSocketHandle], fd: var TFdSet) = + var i = 0 + var L = s.len + while i < L: + if FD_ISSET(s[i], fd) == 0'i32: + s[i] = s[L-1] + dec(L) + else: + inc(i) + setLen(s, L) + +proc select*(readfds: var seq[TSocketHandle], timeout = 500): int = + ## Traditional select function. This function will return the number of + ## sockets that are ready to be read from, written to, or which have errors. + ## If there are none; 0 is returned. + ## ``Timeout`` is in miliseconds and -1 can be specified for no timeout. + ## + ## A socket is removed from the specific ``seq`` when it has data waiting to + ## be read/written to or has errors (``exceptfds``). + var tv {.noInit.}: Ttimeval = timeValFromMilliseconds(timeout) + + var rd: TFdSet + var m = 0 + createFdSet((rd), readfds, m) + + if timeout != -1: + result = int(select(cint(m+1), addr(rd), nil, nil, addr(tv))) + else: + result = int(select(cint(m+1), addr(rd), nil, nil, nil)) + + pruneSocketSet(readfds, (rd)) + +proc selectWrite*(writefds: var seq[TSocketHandle], + timeout = 500): int {.tags: [FReadIO].} = + ## When a socket in ``writefds`` is ready to be written to then a non-zero + ## value will be returned specifying the count of the sockets which can be + ## written to. The sockets which can be written to will also be removed + ## from ``writefds``. + ## + ## ``timeout`` is specified in miliseconds and ``-1`` can be specified for + ## an unlimited time. + var tv {.noInit.}: Ttimeval = timeValFromMilliseconds(timeout) + + var wr: TFdSet + var m = 0 + createFdSet((wr), writefds, m) + + if timeout != -1: + result = int(select(cint(m+1), nil, addr(wr), nil, addr(tv))) + else: + result = int(select(cint(m+1), nil, addr(wr), nil, nil)) + + pruneSocketSet(writefds, (wr)) + +when defined(Windows): + var wsa: TWSADATA + if WSAStartup(0x0101'i16, addr wsa) != 0: OSError(OSLastError()) |