/* * Windows networking abstraction. * * For the IPv6 code in here I am indebted to Jeroen Massar and * unfix.org. */ #include <stdio.h> #include <stdlib.h> #include <assert.h> #define DEFINE_PLUG_METHOD_MACROS #include "putty.h" #include "network.h" #include "tree234.h" #include <ws2tcpip.h> #ifndef NO_IPV6 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT; const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT; #endif #define ipv4_is_loopback(addr) \ ((p_ntohl(addr.s_addr) & 0xFF000000L) == 0x7F000000L) /* * We used to typedef struct Socket_tag *Socket. * * Since we have made the networking abstraction slightly more * abstract, Socket no longer means a tcp socket (it could mean * an ssl socket). So now we must use Actual_Socket when we know * we are talking about a tcp socket. */ typedef struct Socket_tag *Actual_Socket; /* * Mutable state that goes with a SockAddr: stores information * about where in the list of candidate IP(v*) addresses we've * currently got to. */ typedef struct SockAddrStep_tag SockAddrStep; struct SockAddrStep_tag { #ifndef NO_IPV6 struct addrinfo *ai; /* steps along addr->ais */ #endif int curraddr; }; struct Socket_tag { const struct socket_function_table *fn; /* the above variable absolutely *must* be the first in this structure */ char *error; SOCKET s; Plug plug; void *private_ptr; bufchain output_data; int connected; int writable; int frozen; /* this causes readability notifications to be ignored */ int frozen_readable; /* this means we missed at least one readability * notification while we were frozen */ int localhost_only; /* for listening sockets */ char oobdata[1]; int sending_oob; int oobinline, nodelay, keepalive, privport; SockAddr addr; SockAddrStep step; int port; int pending_error; /* in case send() returns error */ /* * We sometimes need pairs of Socket structures to be linked: * if we are listening on the same IPv6 and v4 port, for * example. So here we define `parent' and `child' pointers to * track this link. */ Actual_Socket parent, child; }; struct SockAddr_tag { int refcount; char *error; int resolved; #ifndef NO_IPV6 struct addrinfo *ais; /* Addresses IPv6 style. */ #endif unsigned long *addresses; /* Addresses IPv4 style. */ int naddresses; char hostname[512]; /* Store an unresolved host name. */ }; /* * Which address family this address belongs to. AF_INET for IPv4; * AF_INET6 for IPv6; AF_UNSPEC indicates that name resolution has * not been done and a simple host name is held in this SockAddr * structure. */ #ifndef NO_IPV6 #define SOCKADDR_FAMILY(addr, step) \ (!(addr)->resolved ? AF_UNSPEC : \ (step).ai ? (step).ai->ai_family : AF_INET) #else #define SOCKADDR_FAMILY(addr, step) \ (!(addr)->resolved ? AF_UNSPEC : AF_INET) #endif /* * Start a SockAddrStep structure to step through multiple * addresses. */ #ifndef NO_IPV6 #define START_STEP(addr, step) \ ((step).ai = (addr)->ais, (step).curraddr = 0) #else #define START_STEP(addr, step) \ ((step).curraddr = 0) #endif static tree234 *sktree; static int cmpfortree(void *av, void *bv) { Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv; unsigned long as = (unsigned long) a->s, bs = (unsigned long) b->s; if (as < bs) return -1; if (as > bs) return +1; if (a < b) return -1; if (a > b) return +1; return 0; } static int cmpforsearch(void *av, void *bv) { Actual_Socket b = (Actual_Socket) bv; unsigned long as = (unsigned long) av, bs = (unsigned long) b->s; if (as < bs) return -1; if (as > bs) return +1; return 0; } #define NOTHING #define DECL_WINSOCK_FUNCTION(linkage, rettype, name, params) \ typedef rettype (WINAPI *t_##name) params; \ linkage t_##name p_##name #define GET_WINSOCK_FUNCTION(module, name) \ p_##name = module ? (t_##name) GetProcAddress(module, #name) : NULL DECL_WINSOCK_FUNCTION(NOTHING, int, WSAAsyncSelect, (SOCKET, HWND, u_int, long)); DECL_WINSOCK_FUNCTION(NOTHING, int, WSAEventSelect, (SOCKET, WSAEVENT, long)); DECL_WINSOCK_FUNCTION(NOTHING, int, select, (int, fd_set FAR *, fd_set FAR *, fd_set FAR *, const struct timeval FAR *)); DECL_WINSOCK_FUNCTION(NOTHING, int, WSAGetLastError, (void)); DECL_WINSOCK_FUNCTION(NOTHING, int, WSAEnumNetworkEvents, (SOCKET, WSAEVENT, LPWSANETWORKEVENTS)); DECL_WINSOCK_FUNCTION(static, int, WSAStartup, (WORD, LPWSADATA)); DECL_WINSOCK_FUNCTION(static, int, WSACleanup, (void)); DECL_WINSOCK_FUNCTION(static, int, closesocket, (SOCKET)); DECL_WINSOCK_FUNCTION(static, u_long, ntohl, (u_long)); DECL_WINSOCK_FUNCTION(static, u_long, htonl, (u_long)); DECL_WINSOCK_FUNCTION(static, u_short, htons, (u_short)); DECL_WINSOCK_FUNCTION(static, u_short, ntohs, (u_short)); DECL_WINSOCK_FUNCTION(static, int, gethostname, (char *, int)); DECL_WINSOCK_FUNCTION(static, struct hostent FAR *, gethostbyname, (const char FAR *)); DECL_WINSOCK_FUNCTION(static, struct servent FAR *, getservbyname, (const char FAR *, const char FAR *)); DECL_WINSOCK_FUNCTION(static, unsigned long, inet_addr, (const char FAR *)); DECL_WINSOCK_FUNCTION(static, char FAR *, inet_ntoa, (struct in_addr)); DECL_WINSOCK_FUNCTION(static, int, connect, (SOCKET, const struct sockaddr FAR *, int)); DECL_WINSOCK_FUNCTION(static, int, bind, (SOCKET, const struct sockaddr FAR *, int)); DECL_WINSOCK_FUNCTION(static, int, setsockopt, (SOCKET, int, int, const char FAR *, int)); DECL_WINSOCK_FUNCTION(static, SOCKET, socket, (int, int, int)); DECL_WINSOCK_FUNCTION(static, int, listen, (SOCKET, int)); DECL_WINSOCK_FUNCTION(static, int, send, (SOCKET, const char FAR *, int, int)); DECL_WINSOCK_FUNCTION(static, int, ioctlsocket, (SOCKET, long, u_long FAR *)); DECL_WINSOCK_FUNCTION(static, SOCKET, accept, (SOCKET, struct sockaddr FAR *, int FAR *)); DECL_WINSOCK_FUNCTION(static, int, recv, (SOCKET, char FAR *, int, int)); DECL_WINSOCK_FUNCTION(static, int, WSAIoctl, (SOCKET, DWORD, LPVOID, DWORD, LPVOID, DWORD, LPDWORD, LPWSAOVERLAPPED, LPWSAOVERLAPPED_COMPLETION_ROUTINE)); #ifndef NO_IPV6 DECL_WINSOCK_FUNCTION(static, int, getaddrinfo, (const char *nodename, const char *servname, const struct addrinfo *hints, struct addrinfo **res)); DECL_WINSOCK_FUNCTION(static, void, freeaddrinfo, (struct addrinfo *res)); DECL_WINSOCK_FUNCTION(static, int, getnameinfo, (const struct sockaddr FAR * sa, socklen_t salen, char FAR * host, size_t hostlen, char FAR * serv, size_t servlen, int flags)); DECL_WINSOCK_FUNCTION(static, char *, gai_strerror, (int ecode)); DECL_WINSOCK_FUNCTION(static, int, WSAAddressToStringA, (LPSOCKADDR, DWORD, LPWSAPROTOCOL_INFO, LPTSTR, LPDWORD)); #endif static HMODULE winsock_module = NULL; static WSADATA wsadata; #ifndef NO_IPV6 static HMODULE winsock2_module = NULL; static HMODULE wship6_module = NULL; #endif int sk_startup(int hi, int lo) { WORD winsock_ver; winsock_ver = MAKEWORD(hi, lo); if (p_WSAStartup(winsock_ver, &wsadata)) { return FALSE; } if (LOBYTE(wsadata.wVersion) != LOBYTE(winsock_ver)) { return FALSE; } #ifdef NET_SETUP_DIAGNOSTICS { char buf[80]; sprintf(buf, "Using WinSock %d.%d", hi, lo); logevent(NULL, buf); } #endif return TRUE; } void sk_init(void) { #ifndef NO_IPV6 winsock2_module = #endif winsock_module = LoadLibrary("WS2_32.DLL"); if (!winsock_module) { winsock_module = LoadLibrary("WSOCK32.DLL"); } if (!winsock_module) fatalbox("Unable to load any WinSock library"); #ifndef NO_IPV6 /* Check if we have getaddrinfo in Winsock */ if (GetProcAddress(winsock_module, "getaddrinfo") != NULL) { #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "Native WinSock IPv6 support detected"); #endif GET_WINSOCK_FUNCTION(winsock_module, getaddrinfo); GET_WINSOCK_FUNCTION(winsock_module, freeaddrinfo); GET_WINSOCK_FUNCTION(winsock_module, getnameinfo); GET_WINSOCK_FUNCTION(winsock_module, gai_strerror); } else { /* Fall back to wship6.dll for Windows 2000 */ wship6_module = LoadLibrary("wship6.dll"); if (wship6_module) { #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "WSH IPv6 support detected"); #endif GET_WINSOCK_FUNCTION(wship6_module, getaddrinfo); GET_WINSOCK_FUNCTION(wship6_module, freeaddrinfo); GET_WINSOCK_FUNCTION(wship6_module, getnameinfo); GET_WINSOCK_FUNCTION(wship6_module, gai_strerror); } else { #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "No IPv6 support detected"); #endif } } GET_WINSOCK_FUNCTION(winsock2_module, WSAAddressToStringA); #else #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "PuTTY was built without IPv6 support"); #endif #endif GET_WINSOCK_FUNCTION(winsock_module, WSAAsyncSelect); GET_WINSOCK_FUNCTION(winsock_module, WSAEventSelect); GET_WINSOCK_FUNCTION(winsock_module, select); GET_WINSOCK_FUNCTION(winsock_module, WSAGetLastError); GET_WINSOCK_FUNCTION(winsock_module, WSAEnumNetworkEvents); GET_WINSOCK_FUNCTION(winsock_module, WSAStartup); GET_WINSOCK_FUNCTION(winsock_module, WSACleanup); GET_WINSOCK_FUNCTION(winsock_module, closesocket); GET_WINSOCK_FUNCTION(winsock_module, ntohl); GET_WINSOCK_FUNCTION(winsock_module, htonl); GET_WINSOCK_FUNCTION(winsock_module, htons); GET_WINSOCK_FUNCTION(winsock_module, ntohs); GET_WINSOCK_FUNCTION(winsock_module, gethostname); GET_WINSOCK_FUNCTION(winsock_module, gethostbyname); GET_WINSOCK_FUNCTION(winsock_module, getservbyname); GET_WINSOCK_FUNCTION(winsock_module, inet_addr); GET_WINSOCK_FUNCTION(winsock_module, inet_ntoa); GET_WINSOCK_FUNCTION(winsock_module, connect); GET_WINSOCK_FUNCTION(winsock_module, bind); GET_WINSOCK_FUNCTION(winsock_module, setsockopt); GET_WINSOCK_FUNCTION(winsock_module, socket); GET_WINSOCK_FUNCTION(winsock_module, listen); GET_WINSOCK_FUNCTION(winsock_module, send); GET_WINSOCK_FUNCTION(winsock_module, ioctlsocket); GET_WINSOCK_FUNCTION(winsock_module, accept); GET_WINSOCK_FUNCTION(winsock_module, recv); GET_WINSOCK_FUNCTION(winsock_module, WSAIoctl); /* Try to get the best WinSock version we can get */ if (!sk_startup(2,2) && !sk_startup(2,0) && !sk_startup(1,1)) { fatalbox("Unable to initialise WinSock"); } sktree = newtree234(cmpfortree); } void sk_cleanup(void) { Actual_Socket s; int i; if (sktree) { for (i = 0; (s = index234(sktree, i)) != NULL; i++) { p_closesocket(s->s); } freetree234(sktree); sktree = NULL; } p_WSACleanup(); if (winsock_module) FreeLibrary(winsock_module); #ifndef NO_IPV6 if (wship6_module) FreeLibrary(wship6_module); #endif } char *winsock_error_string(int error) { switch (error) { case WSAEACCES: return "Network error: Permission denied"; case WSAEADDRINUSE: return "Network error: Address already in use"; case WSAEADDRNOTAVAIL: return "Network error: Cannot assign requested address"; case WSAEAFNOSUPPORT: return "Network error: Address family not supported by protocol family"; case WSAEALREADY: return "Network error: Operation already in progress"; case WSAECONNABORTED: return "Network error: Software caused connection abort"; case WSAECONNREFUSED: return "Network error: Connection refused"; case WSAECONNRESET: return "Network error: Connection reset by peer"; case WSAEDESTADDRREQ: return "Network error: Destination address required"; case WSAEFAULT: return "Network error: Bad address"; case WSAEHOSTDOWN: return "Network error: Host is down"; case WSAEHOSTUNREACH: return "Network error: No route to host"; case WSAEINPROGRESS: return "Network error: Operation now in progress"; case WSAEINTR: return "Network error: Interrupted function call"; case WSAEINVAL: return "Network error: Invalid argument"; case WSAEISCONN: return "Network error: Socket is already connected"; case WSAEMFILE: return "Network error: Too many open files"; case WSAEMSGSIZE: return "Network error: Message too long"; case WSAENETDOWN: return "Network error: Network is down"; case WSAENETRESET: return "Network error: Network dropped connection on reset"; case WSAENETUNREACH: return "Network error: Network is unreachable"; case WSAENOBUFS: return "Network error: No buffer space available"; case WSAENOPROTOOPT: return "Network error: Bad protocol option"; case WSAENOTCONN: return "Network error: Socket is not connected"; case WSAENOTSOCK: return "Network error: Socket operation on non-socket"; case WSAEOPNOTSUPP: return "Network error: Operation not supported"; case WSAEPFNOSUPPORT: return "Network error: Protocol family not supported"; case WSAEPROCLIM: return "Network error: Too many processes"; case WSAEPROTONOSUPPORT: return "Network error: Protocol not supported"; case WSAEPROTOTYPE: return "Network error: Protocol wrong type for socket"; case WSAESHUTDOWN: return "Network error: Cannot send after socket shutdown"; case WSAESOCKTNOSUPPORT: return "Network error: Socket type not supported"; case WSAETIMEDOUT: return "Network error: Connection timed out"; case WSAEWOULDBLOCK: return "Network error: Resource temporarily unavailable"; case WSAEDISCON: return "Network error: Graceful shutdown in progress"; default: return "Unknown network error"; } } SockAddr sk_namelookup(const char *host, char **canonicalname, int address_family) { SockAddr ret = snew(struct SockAddr_tag); unsigned long a; struct hostent *h = NULL; char realhost[8192]; int hint_family; int err; /* Default to IPv4. */ hint_family = (address_family == ADDRTYPE_IPV4 ? AF_INET : #ifndef NO_IPV6 address_family == ADDRTYPE_IPV6 ? AF_INET6 : #endif AF_UNSPEC); /* Clear the structure and default to IPv4. */ memset(ret, 0, sizeof(struct SockAddr_tag)); #ifndef NO_IPV6 ret->ais = NULL; #endif ret->addresses = NULL; ret->resolved = FALSE; ret->refcount = 1; *realhost = '\0'; if ((a = p_inet_addr(host)) == (unsigned long) INADDR_NONE) { #ifndef NO_IPV6 /* * Use getaddrinfo when it's available */ if (p_getaddrinfo) { struct addrinfo hints; #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "Using getaddrinfo() for resolving"); #endif memset(&hints, 0, sizeof(hints)); hints.ai_family = hint_family; hints.ai_flags = AI_CANONNAME; if ((err = p_getaddrinfo(host, NULL, &hints, &ret->ais)) == 0) ret->resolved = TRUE; } else #endif { #ifdef NET_SETUP_DIAGNOSTICS logevent(NULL, "Using gethostbyname() for resolving"); #endif /* * Otherwise use the IPv4-only gethostbyname... * (NOTE: we don't use gethostbyname as a fallback!) */ if ( (h = p_gethostbyname(host)) ) ret->resolved = TRUE; else err = p_WSAGetLastError(); } if (!ret->resolved) { ret->error = (err == WSAENETDOWN ? "Network is down" : err == WSAHOST_NOT_FOUND ? "Host does not exist" : err == WSATRY_AGAIN ? "Host not found" : #ifndef NO_IPV6 p_getaddrinfo&&p_gai_strerror ? p_gai_strerror(err) : #endif "gethostbyname: unknown error"); } else { ret->error = NULL; #ifndef NO_IPV6 /* If we got an address info use that... */ if (ret->ais) { /* Are we in IPv4 fallback mode? */ /* We put the IPv4 address into the a variable so we can further-on use the IPv4 code... */ if (ret->ais->ai_family == AF_INET) memcpy(&a, (char *) &((SOCKADDR_IN *) ret->ais-> ai_addr)->sin_addr, sizeof(a)); if (ret->ais->ai_canonname) strncpy(realhost, ret->ais->ai_canonname, lenof(realhost)); else strncpy(realhost, host, lenof(realhost)); } /* We used the IPv4-only gethostbyname()... */ else #endif { int n; for (n = 0; h->h_addr_list[n]; n++); ret->addresses = snewn(n, unsigned long); ret->naddresses = n; for (n = 0; n < ret->naddresses; n++) { memcpy(&a, h->h_addr_list[n], sizeof(a)); ret->addresses[n] = p_ntohl(a); } memcpy(&a, h->h_addr, sizeof(a)); /* This way we are always sure the h->h_name is valid :) */ strncpy(realhost, h->h_name, sizeof(realhost)); } } } else { /* * This must be a numeric IPv4 address because it caused a * success return from inet_addr. */ ret->addresses = snewn(1, unsigned long); ret->naddresses = 1; ret->addresses[0] = p_ntohl(a); ret->resolved = TRUE; strncpy(realhost, host, sizeof(realhost)); } realhost[lenof(realhost)-1] = '\0'; *canonicalname = snewn(1+strlen(realhost), char); strcpy(*canonicalname, realhost); return ret; } SockAddr sk_nonamelookup(const char *host) { SockAddr ret = snew(struct SockAddr_tag); ret->error = NULL; ret->resolved = FALSE; #ifndef NO_IPV6 ret->ais = NULL; #endif ret->addresses = NULL; ret->naddresses = 0; ret->refcount = 1; strncpy(ret->hostname, host, lenof(ret->hostname)); ret->hostname[lenof(ret->hostname)-1] = '\0'; return ret; } int sk_nextaddr(SockAddr addr, SockAddrStep *step) { #ifndef NO_IPV6 if (step->ai) { if (step->ai->ai_next) { step->ai = step->ai->ai_next; return TRUE; } else return FALSE; } #endif if (step->curraddr+1 < addr->naddresses) { step->curraddr++; return TRUE; } else { return FALSE; } } void sk_getaddr(SockAddr addr, char *buf, int buflen) { SockAddrStep step; START_STEP(addr, step); #ifndef NO_IPV6 if (step.ai) { if (p_WSAAddressToStringA) { p_WSAAddressToStringA(step.ai->ai_addr, step.ai->ai_addrlen, NULL, buf, &buflen); } else strncpy(buf, "IPv6", buflen); } else #endif if (SOCKADDR_FAMILY(addr, step) == AF_INET) { struct in_addr a; assert(addr->addresses && step.curraddr < addr->naddresses); a.s_addr = p_htonl(addr->addresses[step.curraddr]); strncpy(buf, p_inet_ntoa(a), buflen); buf[buflen-1] = '\0'; } else { strncpy(buf, addr->hostname, buflen); buf[buflen-1] = '\0'; } } int sk_hostname_is_local(char *name) { return !strcmp(name, "localhost") || !strcmp(name, "::1") || !strncmp(name, "127.", 4); } static INTERFACE_INFO local_interfaces[16]; static int n_local_interfaces; /* 0=not yet, -1=failed, >0=number */ static int ipv4_is_local_addr(struct in_addr addr) { if (ipv4_is_loopback(addr)) return 1; /* loopback addresses are local */ if (!n_local_interfaces) { SOCKET s = p_socket(AF_INET, SOCK_DGRAM, 0); DWORD retbytes; if (p_WSAIoctl && p_WSAIoctl(s, SIO_GET_INTERFACE_LIST, NULL, 0, local_interfaces, sizeof(local_interfaces), &retbytes, NULL, NULL) == 0) n_local_interfaces = retbytes / sizeof(INTERFACE_INFO); else logevent(NULL, "Unable to get list of local IP addresses"); } if (n_local_interfaces > 0) { int i; for (i = 0; i < n_local_interfaces; i++) { SOCKADDR_IN *address = (SOCKADDR_IN *)&local_interfaces[i].iiAddress; if (address->sin_addr.s_addr == addr.s_addr) return 1; /* this address is local */ } } return 0; /* this address is not local */ } int sk_address_is_local(SockAddr addr) { SockAddrStep step; int family; START_STEP(addr, step); family = SOCKADDR_FAMILY(addr, step); #ifndef NO_IPV6 if (family == AF_INET6) { return IN6_IS_ADDR_LOOPBACK((const struct in6_addr *)step.ai->ai_addr); } else #endif if (family == AF_INET) { #ifndef NO_IPV6 if (step.ai) { return ipv4_is_local_addr(((struct sockaddr_in *)step.ai->ai_addr) ->sin_addr); } else #endif { struct in_addr a; assert(addr->addresses && step.curraddr < addr->naddresses); a.s_addr = p_htonl(addr->addresses[step.curraddr]); return ipv4_is_local_addr(a); } } else { assert(family == AF_UNSPEC); return 0; /* we don't know; assume not */ } } int sk_addrtype(SockAddr addr) { SockAddrStep step; int family; START_STEP(addr, step); family = SOCKADDR_FAMILY(addr, step); return (family == AF_INET ? ADDRTYPE_IPV4 : #ifndef NO_IPV6 family == AF_INET6 ? ADDRTYPE_IPV6 : #endif ADDRTYPE_NAME); } void sk_addrcopy(SockAddr addr, char *buf) { SockAddrStep step; int family; START_STEP(addr, step); family = SOCKADDR_FAMILY(addr, step); assert(family != AF_UNSPEC); #ifndef NO_IPV6 if (step.ai) { if (family == AF_INET) memcpy(buf, &((struct sockaddr_in *)step.ai->ai_addr)->sin_addr, sizeof(struct in_addr)); else if (family == AF_INET6) memcpy(buf, &((struct sockaddr_in6 *)step.ai->ai_addr)->sin6_addr, sizeof(struct in6_addr)); else assert(FALSE); } else #endif if (family == AF_INET) { struct in_addr a; assert(addr->addresses && step.curraddr < addr->naddresses); a.s_addr = p_htonl(addr->addresses[step.curraddr]); memcpy(buf, (char*) &a.s_addr, 4); } } void sk_addr_free(SockAddr addr) { if (--addr->refcount > 0) return; #ifndef NO_IPV6 if (addr->ais && p_freeaddrinfo) p_freeaddrinfo(addr->ais); #endif if (addr->addresses) sfree(addr->addresses); sfree(addr); } SockAddr sk_addr_dup(SockAddr addr) { addr->refcount++; return addr; } static Plug sk_tcp_plug(Socket sock, Plug p) { Actual_Socket s = (Actual_Socket) sock; Plug ret = s->plug; if (p) s->plug = p; return ret; } static void sk_tcp_flush(Socket s) { /* * We send data to the socket as soon as we can anyway, * so we don't need to do anything here. :-) */ } static void sk_tcp_close(Socket s); static int sk_tcp_write(Socket s, const char *data, int len); static int sk_tcp_write_oob(Socket s, const char *data, int len); static void sk_tcp_set_private_ptr(Socket s, void *ptr); static void *sk_tcp_get_private_ptr(Socket s); static void sk_tcp_set_frozen(Socket s, int is_frozen); static const char *sk_tcp_socket_error(Socket s); extern char *do_select(SOCKET skt, int startup); Socket sk_register(void *sock, Plug plug) { static const struct socket_function_table fn_table = { sk_tcp_plug, sk_tcp_close, sk_tcp_write, sk_tcp_write_oob, sk_tcp_flush, sk_tcp_set_private_ptr, sk_tcp_get_private_ptr, sk_tcp_set_frozen, sk_tcp_socket_error }; DWORD err; char *errstr; Actual_Socket ret; /* * Create Socket structure. */ ret = snew(struct Socket_tag); ret->fn = &fn_table; ret->error = NULL; ret->plug = plug; bufchain_init(&ret->output_data); ret->writable = 1; /* to start with */ ret->sending_oob = 0; ret->frozen = 1; ret->frozen_readable = 0; ret->localhost_only = 0; /* unused, but best init anyway */ ret->pending_error = 0; ret->parent = ret->child = NULL; ret->addr = NULL; ret->s = (SOCKET)sock; if (ret->s == INVALID_SOCKET) { err = p_WSAGetLastError(); ret->error = winsock_error_string(err); return (Socket) ret; } ret->oobinline = 0; /* Set up a select mechanism. This could be an AsyncSelect on a * window, or an EventSelect on an event object. */ errstr = do_select(ret->s, 1); if (errstr) { ret->error = errstr; return (Socket) ret; } add234(sktree, ret); return (Socket) ret; } static DWORD try_connect(Actual_Socket sock) { SOCKET s; #ifndef NO_IPV6 SOCKADDR_IN6 a6; #endif SOCKADDR_IN a; DWORD err; char *errstr; short localport; int family; if (sock->s != INVALID_SOCKET) { do_select(sock->s, 0); p_closesocket(sock->s); } plug_log(sock->plug, 0, sock->addr, sock->port, NULL, 0); /* * Open socket. */ family = SOCKADDR_FAMILY(sock->addr, sock->step); /* * Remove the socket from the tree before we overwrite its * internal socket id, because that forms part of the tree's * sorting criterion. We'll add it back before exiting this * function, whether we changed anything or not. */ del234(sktree, sock); s = p_socket(family, SOCK_STREAM, 0); sock->s = s; if (s == INVALID_SOCKET) { err = p_WSAGetLastError(); sock->error = winsock_error_string(err); goto ret; } if (sock->oobinline) { BOOL b = TRUE; p_setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b)); } if (sock->nodelay) { BOOL b = TRUE; p_setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b)); } if (sock->keepalive) { BOOL b = TRUE; p_setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, (void *) &b, sizeof(b)); } /* * Bind to local address. */ if (sock->privport) localport = 1023; /* count from 1023 downwards */ else localport = 0; /* just use port 0 (ie winsock picks) */ /* Loop round trying to bind */ while (1) { int sockcode; #ifndef NO_IPV6 if (family == AF_INET6) { memset(&a6, 0, sizeof(a6)); a6.sin6_family = AF_INET6; /*a6.sin6_addr = in6addr_any; */ /* == 0 done by memset() */ a6.sin6_port = p_htons(localport); } else #endif { a.sin_family = AF_INET; a.sin_addr.s_addr = p_htonl(INADDR_ANY); a.sin_port = p_htons(localport); } #ifndef NO_IPV6 sockcode = p_bind(s, (family == AF_INET6 ? (struct sockaddr *) &a6 : (struct sockaddr *) &a), (family == AF_INET6 ? sizeof(a6) : sizeof(a))); #else sockcode = p_bind(s, (struct sockaddr *) &a, sizeof(a)); #endif if (sockcode != SOCKET_ERROR) { err = 0; break; /* done */ } else { err = p_WSAGetLastError(); if (err != WSAEADDRINUSE) /* failed, for a bad reason */ break; } if (localport == 0) break; /* we're only looping once */ localport--; if (localport == 0) break; /* we might have got to the end */ } if (err) { sock->error = winsock_error_string(err); goto ret; } /* * Connect to remote address. */ #ifndef NO_IPV6 if (sock->step.ai) { if (family == AF_INET6) { a6.sin6_family = AF_INET6; a6.sin6_port = p_htons((short) sock->port); a6.sin6_addr = ((struct sockaddr_in6 *) sock->step.ai->ai_addr)->sin6_addr; a6.sin6_flowinfo = ((struct sockaddr_in6 *) sock->step.ai->ai_addr)->sin6_flowinfo; a6.sin6_scope_id = ((struct sockaddr_in6 *) sock->step.ai->ai_addr)->sin6_scope_id; } else { a.sin_family = AF_INET; a.sin_addr = ((struct sockaddr_in *) sock->step.ai->ai_addr)->sin_addr; a.sin_port = p_htons((short) sock->port); } } else #endif { assert(sock->addr->addresses && sock->step.curraddr < sock->addr->naddresses); a.sin_family = AF_INET; a.sin_addr.s_addr = p_htonl(sock->addr->addresses[sock->step.curraddr]); a.sin_port = p_htons((short) sock->port); } /* Set up a select mechanism. This could be an AsyncSelect on a * window, or an EventSelect on an event object. */ errstr = do_select(s, 1); if (errstr) { sock->error = errstr; err = 1; goto ret; } if (( #ifndef NO_IPV6 p_connect(s, ((family == AF_INET6) ? (struct sockaddr *) &a6 : (struct sockaddr *) &a), (family == AF_INET6) ? sizeof(a6) : sizeof(a)) #else p_connect(s, (struct sockaddr *) &a, sizeof(a)) #endif ) == SOCKET_ERROR) { err = p_WSAGetLastError(); /* * We expect a potential EWOULDBLOCK here, because the * chances are the front end has done a select for * FD_CONNECT, so that connect() will complete * asynchronously. */ if ( err != WSAEWOULDBLOCK ) { sock->error = winsock_error_string(err); goto ret; } } else { /* * If we _don't_ get EWOULDBLOCK, the connect has completed * and we should set the socket as writable. */ sock->writable = 1; } err = 0; ret: /* * No matter what happened, put the socket back in the tree. */ add234(sktree, sock); if (err) plug_log(sock->plug, 1, sock->addr, sock->port, sock->error, err); return err; } Socket sk_new(SockAddr addr, int port, int privport, int oobinline, int nodelay, int keepalive, Plug plug) { static const struct socket_function_table fn_table = { sk_tcp_plug, sk_tcp_close, sk_tcp_write, sk_tcp_write_oob, sk_tcp_flush, sk_tcp_set_private_ptr, sk_tcp_get_private_ptr, sk_tcp_set_frozen, sk_tcp_socket_error }; Actual_Socket ret; DWORD err; /* * Create Socket structure. */ ret = snew(struct Socket_tag); ret->fn = &fn_table; ret->error = NULL; ret->plug = plug; bufchain_init(&ret->output_data); ret->connected = 0; /* to start with */ ret->writable = 0; /* to start with */ ret->sending_oob = 0; ret->frozen = 0; ret->frozen_readable = 0; ret->localhost_only = 0; /* unused, but best init anyway */ ret->pending_error = 0; ret->parent = ret->child = NULL; ret->oobinline = oobinline; ret->nodelay = nodelay; ret->keepalive = keepalive; ret->privport = privport; ret->port = port; ret->addr = addr; START_STEP(ret->addr, ret->step); ret->s = INVALID_SOCKET; err = 0; do { err = try_connect(ret); } while (err && sk_nextaddr(ret->addr, &ret->step)); return (Socket) ret; } Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only, int orig_address_family) { static const struct socket_function_table fn_table = { sk_tcp_plug, sk_tcp_close, sk_tcp_write, sk_tcp_write_oob, sk_tcp_flush, sk_tcp_set_private_ptr, sk_tcp_get_private_ptr, sk_tcp_set_frozen, sk_tcp_socket_error }; SOCKET s; #ifndef NO_IPV6 SOCKADDR_IN6 a6; #endif SOCKADDR_IN a; DWORD err; char *errstr; Actual_Socket ret; int retcode; int on = 1; int address_family; /* * Create Socket structure. */ ret = snew(struct Socket_tag); ret->fn = &fn_table; ret->error = NULL; ret->plug = plug; bufchain_init(&ret->output_data); ret->writable = 0; /* to start with */ ret->sending_oob = 0; ret->frozen = 0; ret->frozen_readable = 0; ret->localhost_only = local_host_only; ret->pending_error = 0; ret->parent = ret->child = NULL; ret->addr = NULL; /* * Translate address_family from platform-independent constants * into local reality. */ address_family = (orig_address_family == ADDRTYPE_IPV4 ? AF_INET : #ifndef NO_IPV6 orig_address_family == ADDRTYPE_IPV6 ? AF_INET6 : #endif AF_UNSPEC); /* * Our default, if passed the `don't care' value * ADDRTYPE_UNSPEC, is to listen on IPv4. If IPv6 is supported, * we will also set up a second socket listening on IPv6, but * the v4 one is primary since that ought to work even on * non-v6-supporting systems. */ if (address_family == AF_UNSPEC) address_family = AF_INET; /* * Open socket. */ s = p_socket(address_family, SOCK_STREAM, 0); ret->s = s; if (s == INVALID_SOCKET) { err = p_WSAGetLastError(); ret->error = winsock_error_string(err); return (Socket) ret; } ret->oobinline = 0; p_setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on)); #ifndef NO_IPV6 if (address_family == AF_INET6) { memset(&a6, 0, sizeof(a6)); a6.sin6_family = AF_INET6; /* FIXME: srcaddr is ignored for IPv6, because I (SGT) don't * know how to do it. :-) * (jeroen:) saddr is specified as an address.. eg 2001:db8::1 * Thus we need either a parser that understands [2001:db8::1]:80 * style addresses and/or enhance this to understand hostnames too. */ if (local_host_only) a6.sin6_addr = in6addr_loopback; else a6.sin6_addr = in6addr_any; a6.sin6_port = p_htons(port); } else #endif { int got_addr = 0; a.sin_family = AF_INET; /* * Bind to source address. First try an explicitly * specified one... */ if (srcaddr) { a.sin_addr.s_addr = p_inet_addr(srcaddr); if (a.sin_addr.s_addr != INADDR_NONE) { /* Override localhost_only with specified listen addr. */ ret->localhost_only = ipv4_is_loopback(a.sin_addr); got_addr = 1; } } /* * ... and failing that, go with one of the standard ones. */ if (!got_addr) { if (local_host_only) a.sin_addr.s_addr = p_htonl(INADDR_LOOPBACK); else a.sin_addr.s_addr = p_htonl(INADDR_ANY); } a.sin_port = p_htons((short)port); } #ifndef NO_IPV6 retcode = p_bind(s, (address_family == AF_INET6 ? (struct sockaddr *) &a6 : (struct sockaddr *) &a), (address_family == AF_INET6 ? sizeof(a6) : sizeof(a))); #else retcode = p_bind(s, (struct sockaddr *) &a, sizeof(a)); #endif if (retcode != SOCKET_ERROR) { err = 0; } else { err = p_WSAGetLastError(); } if (err) { p_closesocket(s); ret->error = winsock_error_string(err); return (Socket) ret; } if (p_listen(s, SOMAXCONN) == SOCKET_ERROR) { p_closesocket(s); ret->error = winsock_error_string(err); return (Socket) ret; } /* Set up a select mechanism. This could be an AsyncSelect on a * window, or an EventSelect on an event object. */ errstr = do_select(s, 1); if (errstr) { p_closesocket(s); ret->error = errstr; return (Socket) ret; } add234(sktree, ret); #ifndef NO_IPV6 /* * If we were given ADDRTYPE_UNSPEC, we must also create an * IPv6 listening socket and link it to this one. */ if (address_family == AF_INET && orig_address_family == ADDRTYPE_UNSPEC) { Actual_Socket other; other = (Actual_Socket) sk_newlistener(srcaddr, port, plug, local_host_only, ADDRTYPE_IPV6); if (other) { if (!other->error) { other->parent = ret; ret->child = other; } else { sfree(other); } } } #endif return (Socket) ret; } static void sk_tcp_close(Socket sock) { extern char *do_select(SOCKET skt, int startup); Actual_Socket s = (Actual_Socket) sock; if (s->child) sk_tcp_close((Socket)s->child); del234(sktree, s); do_select(s->s, 0); p_closesocket(s->s); if (s->addr) sk_addr_free(s->addr); sfree(s); } /* * The function which tries to send on a socket once it's deemed * writable. */ void try_send(Actual_Socket s) { while (s->sending_oob || bufchain_size(&s->output_data) > 0) { int nsent; DWORD err; void *data; int len, urgentflag; if (s->sending_oob) { urgentflag = MSG_OOB; len = s->sending_oob; data = &s->oobdata; } else { urgentflag = 0; bufchain_prefix(&s->output_data, &data, &len); } nsent = p_send(s->s, data, len, urgentflag); noise_ultralight(nsent); if (nsent <= 0) { err = (nsent < 0 ? p_WSAGetLastError() : 0); if ((err < WSABASEERR && nsent < 0) || err == WSAEWOULDBLOCK) { /* * Perfectly normal: we've sent all we can for the moment. * * (Some WinSock send() implementations can return * <0 but leave no sensible error indication - * WSAGetLastError() is called but returns zero or * a small number - so we check that case and treat * it just like WSAEWOULDBLOCK.) */ s->writable = FALSE; return; } else if (nsent == 0 || err == WSAECONNABORTED || err == WSAECONNRESET) { /* * If send() returns CONNABORTED or CONNRESET, we * unfortunately can't just call plug_closing(), * because it's quite likely that we're currently * _in_ a call from the code we'd be calling back * to, so we'd have to make half the SSH code * reentrant. Instead we flag a pending error on * the socket, to be dealt with (by calling * plug_closing()) at some suitable future moment. */ s->pending_error = err; return; } else { /* We're inside the Windows frontend here, so we know * that the frontend handle is unnecessary. */ logevent(NULL, winsock_error_string(err)); fatalbox("%s", winsock_error_string(err)); } } else { if (s->sending_oob) { if (nsent < len) { memmove(s->oobdata, s->oobdata+nsent, len-nsent); s->sending_oob = len - nsent; } else { s->sending_oob = 0; } } else { bufchain_consume(&s->output_data, nsent); } } } } static int sk_tcp_write(Socket sock, const char *buf, int len) { Actual_Socket s = (Actual_Socket) sock; /* * Add the data to the buffer list on the socket. */ bufchain_add(&s->output_data, buf, len); /* * Now try sending from the start of the buffer list. */ if (s->writable) try_send(s); return bufchain_size(&s->output_data); } static int sk_tcp_write_oob(Socket sock, const char *buf, int len) { Actual_Socket s = (Actual_Socket) sock; /* * Replace the buffer list on the socket with the data. */ bufchain_clear(&s->output_data); assert(len <= sizeof(s->oobdata)); memcpy(s->oobdata, buf, len); s->sending_oob = len; /* * Now try sending from the start of the buffer list. */ if (s->writable) try_send(s); return s->sending_oob; } int select_result(WPARAM wParam, LPARAM lParam) { int ret, open; DWORD err; char buf[20480]; /* nice big buffer for plenty of speed */ Actual_Socket s; u_long atmark; /* wParam is the socket itself */ if (wParam == 0) return 1; /* boggle */ s = find234(sktree, (void *) wParam, cmpforsearch); if (!s) return 1; /* boggle */ if ((err = WSAGETSELECTERROR(lParam)) != 0) { /* * An error has occurred on this socket. Pass it to the * plug. */ if (s->addr) { plug_log(s->plug, 1, s->addr, s->port, winsock_error_string(err), err); while (s->addr && sk_nextaddr(s->addr, &s->step)) { err = try_connect(s); } } if (err != 0) return plug_closing(s->plug, winsock_error_string(err), err, 0); else return 1; } noise_ultralight(lParam); switch (WSAGETSELECTEVENT(lParam)) { case FD_CONNECT: s->connected = s->writable = 1; /* * Once a socket is connected, we can stop falling * back through the candidate addresses to connect * to. */ if (s->addr) { sk_addr_free(s->addr); s->addr = NULL; } break; case FD_READ: /* In the case the socket is still frozen, we don't even bother */ if (s->frozen) { s->frozen_readable = 1; break; } /* * We have received data on the socket. For an oobinline * socket, this might be data _before_ an urgent pointer, * in which case we send it to the back end with type==1 * (data prior to urgent). */ if (s->oobinline) { atmark = 1; p_ioctlsocket(s->s, SIOCATMARK, &atmark); /* * Avoid checking the return value from ioctlsocket(), * on the grounds that some WinSock wrappers don't * support it. If it does nothing, we get atmark==1, * which is equivalent to `no OOB pending', so the * effect will be to non-OOB-ify any OOB data. */ } else atmark = 1; ret = p_recv(s->s, buf, sizeof(buf), 0); noise_ultralight(ret); if (ret < 0) { err = p_WSAGetLastError(); if (err == WSAEWOULDBLOCK) { break; } } if (ret < 0) { return plug_closing(s->plug, winsock_error_string(err), err, 0); } else if (0 == ret) { return plug_closing(s->plug, NULL, 0, 0); } else { return plug_receive(s->plug, atmark ? 0 : 1, buf, ret); } break; case FD_OOB: /* * This will only happen on a non-oobinline socket. It * indicates that we can immediately perform an OOB read * and get back OOB data, which we will send to the back * end with type==2 (urgent data). */ ret = p_recv(s->s, buf, sizeof(buf), MSG_OOB); noise_ultralight(ret); if (ret <= 0) { char *str = (ret == 0 ? "Internal networking trouble" : winsock_error_string(p_WSAGetLastError())); /* We're inside the Windows frontend here, so we know * that the frontend handle is unnecessary. */ logevent(NULL, str); fatalbox("%s", str); } else { return plug_receive(s->plug, 2, buf, ret); } break; case FD_WRITE: { int bufsize_before, bufsize_after; s->writable = 1; bufsize_before = s->sending_oob + bufchain_size(&s->output_data); try_send(s); bufsize_after = s->sending_oob + bufchain_size(&s->output_data); if (bufsize_after < bufsize_before) plug_sent(s->plug, bufsize_after); } break; case FD_CLOSE: /* Signal a close on the socket. First read any outstanding data. */ open = 1; do { ret = p_recv(s->s, buf, sizeof(buf), 0); if (ret < 0) { err = p_WSAGetLastError(); if (err == WSAEWOULDBLOCK) break; return plug_closing(s->plug, winsock_error_string(err), err, 0); } else { if (ret) open &= plug_receive(s->plug, 0, buf, ret); else open &= plug_closing(s->plug, NULL, 0, 0); } } while (ret > 0); return open; case FD_ACCEPT: { #ifdef NO_IPV6 struct sockaddr_in isa; #else struct sockaddr_storage isa; #endif int addrlen = sizeof(isa); SOCKET t; /* socket of connection */ memset(&isa, 0, sizeof(isa)); err = 0; t = p_accept(s->s,(struct sockaddr *)&isa,&addrlen); if (t == INVALID_SOCKET) { err = p_WSAGetLastError(); if (err == WSATRY_AGAIN) break; } #ifndef NO_IPV6 if (isa.ss_family == AF_INET && s->localhost_only && !ipv4_is_local_addr(((struct sockaddr_in *)&isa)->sin_addr)) #else if (s->localhost_only && !ipv4_is_local_addr(isa.sin_addr)) #endif { p_closesocket(t); /* dodgy WinSock let nonlocal through */ } else if (plug_accepting(s->plug, (void*)t)) { p_closesocket(t); /* denied or error */ } } } return 1; } /* * Deal with socket errors detected in try_send(). */ void net_pending_errors(void) { int i; Actual_Socket s; /* * This might be a fiddly business, because it's just possible * that handling a pending error on one socket might cause * others to be closed. (I can't think of any reason this might * happen in current SSH implementation, but to maintain * generality of this network layer I'll assume the worst.) * * So what we'll do is search the socket list for _one_ socket * with a pending error, and then handle it, and then search * the list again _from the beginning_. Repeat until we make a * pass with no socket errors present. That way we are * protected against the socket list changing under our feet. */ do { for (i = 0; (s = index234(sktree, i)) != NULL; i++) { if (s->pending_error) { /* * An error has occurred on this socket. Pass it to the * plug. */ plug_closing(s->plug, winsock_error_string(s->pending_error), s->pending_error, 0); break; } } } while (s); } /* * Each socket abstraction contains a `void *' private field in * which the client can keep state. */ static void sk_tcp_set_private_ptr(Socket sock, void *ptr) { Actual_Socket s = (Actual_Socket) sock; s->private_ptr = ptr; } static void *sk_tcp_get_private_ptr(Socket sock) { Actual_Socket s = (Actual_Socket) sock; return s->private_ptr; } /* * Special error values are returned from sk_namelookup and sk_new * if there's a problem. These functions extract an error message, * or return NULL if there's no problem. */ const char *sk_addr_error(SockAddr addr) { return addr->error; } static const char *sk_tcp_socket_error(Socket sock) { Actual_Socket s = (Actual_Socket) sock; return s->error; } static void sk_tcp_set_frozen(Socket sock, int is_frozen) { Actual_Socket s = (Actual_Socket) sock; if (s->frozen == is_frozen) return; s->frozen = is_frozen; if (!is_frozen) { do_select(s->s, 1); if (s->frozen_readable) { char c; p_recv(s->s, &c, 1, MSG_PEEK); } } s->frozen_readable = 0; } void socket_reselect_all(void) { Actual_Socket s; int i; for (i = 0; (s = index234(sktree, i)) != NULL; i++) { if (!s->frozen) do_select(s->s, 1); } } /* * For Plink: enumerate all sockets currently active. */ SOCKET first_socket(int *state) { Actual_Socket s; *state = 0; s = index234(sktree, (*state)++); return s ? s->s : INVALID_SOCKET; } SOCKET next_socket(int *state) { Actual_Socket s = index234(sktree, (*state)++); return s ? s->s : INVALID_SOCKET; } extern int socket_writable(SOCKET skt) { Actual_Socket s = find234(sktree, (void *)skt, cmpforsearch); if (s) return bufchain_size(&s->output_data) > 0; else return 0; } int net_service_lookup(char *service) { struct servent *se; se = p_getservbyname(service, NULL); if (se != NULL) return p_ntohs(se->s_port); else return 0; } char *get_hostname(void) { int len = 128; char *hostname = NULL; do { len *= 2; hostname = sresize(hostname, len, char); if (p_gethostname(hostname, len) < 0) { sfree(hostname); hostname = NULL; break; } } while (strlen(hostname) >= len-1); return hostname; } SockAddr platform_get_x11_unix_address(const char *display, int displaynum, char **canonicalname) { SockAddr ret = snew(struct SockAddr_tag); memset(ret, 0, sizeof(struct SockAddr_tag)); ret->error = "unix sockets not supported on this platform"; ret->refcount = 1; return ret; }