/*
* Windows networking abstraction.
*
* Due to this clean abstraction it was possible
* to easily implement IPv6 support :)
*
* IPv6 patch 1 (27 October 2000) Jeroen Massar <jeroen@unfix.org>
* - Preliminary hacked IPv6 support.
* - Connecting to IPv6 address (eg fec0:4242:4242:100:2d0:b7ff:fe8f:5d42) works.
* - Connecting to IPv6 hostname (eg heaven.ipv6.unfix.org) works.
* - Compiles as either IPv4 or IPv6.
*
* IPv6 patch 2 (29 October 2000) Jeroen Massar <jeroen@unfix.org>
* - When compiled as IPv6 it also allows connecting to IPv4 hosts.
* - Added some more documentation.
*
* IPv6 patch 3 (18 November 2000) Jeroen Massar <jeroen@unfix.org>
* - It now supports dynamically loading the IPv6 resolver dll's.
* This way we should be able to distribute one (1) binary
* which supports both IPv4 and IPv6.
* - getaddrinfo() and getnameinfo() are loaded dynamicaly if possible.
* - in6addr_any is defined in this file so we don't need to link to wship6.lib
* - The patch is now more unified so that we can still
* remove all IPv6 support by undef'ing IPV6.
* But where it fallsback to IPv4 it uses the IPv4 code which is already in place...
* - Canonical name resolving works.
*
* IPv6 patch 4 (07 January 2001) Jeroen Massar <jeroen@unfix.org>
* - patch against CVS of today, will be submitted to the bugs list
* as a 'cvs diff -u' on Simon's request...
*
*/
/*
* Define IPV6 to have IPv6 on-the-fly-loading support.
* This means that one doesn't have to have an IPv6 stack to use it.
* But if an IPv6 stack is found it is used with a fallback to IPv4.
*/
/* #define IPV6 1 */
#ifdef IPV6
#include <winsock2.h>
#include <ws2tcpip.h>
#include <tpipv6.h>
#else
#include <winsock.h>
#endif
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#define DEFINE_PLUG_METHOD_MACROS
#include "putty.h"
#include "network.h"
#include "tree234.h"
#define BUFFER_GRANULE 512
struct Socket_tag {
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;
struct buffer *head, *tail;
int writable;
int sending_oob;
int oobinline;
};
/*
* 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;
struct SockAddr_tag {
char *error;
/* address family this belongs to, AF_INET for IPv4, AF_INET6 for IPv6. */
int family;
unsigned long address; /* Address IPv4 style. */
#ifdef IPV6
struct addrinfo *ai; /* Address IPv6 style. */
#endif
/*
* We need to have this lengthy enough to hold *any* hostname
* (including IPv6 reverse...)
*/
char realhost[8192];
};
struct buffer {
struct buffer *next;
int buflen, bufpos;
char buf[BUFFER_GRANULE];
};
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;
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;
}
void sk_init(void) {
sktree = newtree234(cmpfortree);
}
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(char *host, char **canonicalname)
{
SockAddr ret = smalloc(sizeof(struct SockAddr_tag));
unsigned long a;
struct hostent *h = NULL;
/* Clear the structure and default to IPv4. */
memset(ret, 0, sizeof(struct SockAddr_tag));
ret->family = 0; /* We set this one when we have resolved the host. */
*canonicalname = ret->realhost; /* This makes sure we always have a hostname to return. */
if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE)
{
#ifdef IPV6
/* Try to get the getaddrinfo() function from wship6.dll */
/* This way one doesn't need to have IPv6 dll's to use PuTTY and
* it will fallback to IPv4. */
typedef int (CALLBACK* FGETADDRINFO)(const char *nodename,
const char *servname,
const struct addrinfo *hints,
struct addrinfo **res);
FGETADDRINFO fGetAddrInfo = NULL;
HINSTANCE dllWSHIP6 = LoadLibrary("wship6.dll");
if (dllWSHIP6)
fGetAddrInfo = (FGETADDRINFO)GetProcAddress(dllWSHIP6,
"getaddrinfo");
/*
* Use fGetAddrInfo when it's available (which usually also
* means IPv6 is installed...)
*/
if (fGetAddrInfo)
{
/*debug(("Resolving \"%s\" with getaddrinfo() (IPv4+IPv6 capable)...\n", host)); */
if (fGetAddrInfo(host, NULL, NULL, &ret->ai) == 0)
ret->family = ret->ai->ai_family;
}
else
#endif
/*
* Otherwise use the IPv4-only gethostbyname...
* (NOTE: we don't use gethostbyname as a
* fallback!)
*/
if (ret->family == 0)
{
/*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
if (h = gethostbyname(host)) ret->family = AF_INET;
}
/*debug(("Done resolving...(family is %d) AF_INET = %d, AF_INET6 = %d\n", ret->family, AF_INET, AF_INET6)); */
if (ret->family == 0)
{
DWORD err = WSAGetLastError();
ret->error = (err == WSAENETDOWN ? "Network is down" :
err == WSAHOST_NOT_FOUND ? "Host does not exist" :
err == WSATRY_AGAIN ? "Host not found" :
#ifdef IPV6
fGetAddrInfo ? "getaddrinfo: unknown error" :
#endif
"gethostbyname: unknown error");
#ifdef DEBUG
{
LPVOID lpMsgBuf;
FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, err, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR)&lpMsgBuf, 0, NULL);
/*debug(("Error %ld: %s (h=%lx)\n", err, lpMsgBuf, h));*/
/* Free the buffer. */
LocalFree(lpMsgBuf);
}
#endif
}
else
{
ret->error = NULL;
#ifdef IPV6
/* If we got an address info use that... */
if (ret->ai)
{
typedef int (CALLBACK* FGETNAMEINFO)
(const struct sockaddr FAR *sa, socklen_t salen,
char FAR * host, size_t hostlen, char FAR * serv,
size_t servlen, int flags);
FGETNAMEINFO fGetNameInfo = NULL;
/* 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->family == AF_INET)
memcpy(&a, (char *)&((SOCKADDR_IN *)ret->ai->ai_addr)->sin_addr, sizeof(a));
/* Now let's find that canonicalname... */
if ((dllWSHIP6) && (fGetNameInfo = (FGETNAMEINFO)GetProcAddress(dllWSHIP6, "getnameinfo")))
{
if (fGetNameInfo((struct sockaddr *)ret->ai->ai_addr,
ret->family == AF_INET ?
sizeof(SOCKADDR_IN) :
sizeof(SOCKADDR_IN6), ret->realhost,
sizeof(ret->realhost), NULL,
0, 0) != 0)
{
strncpy(ret->realhost, host,
sizeof(ret->realhost));
}
}
}
/* We used the IPv4-only gethostbyname()... */
else
{
#endif
memcpy(&a, h->h_addr, sizeof(a));
/* This way we are always sure the h->h_name is valid :) */
strncpy(ret->realhost, h->h_name, sizeof(ret->realhost));
#ifdef IPV6
}
#endif
}
#ifdef IPV6
FreeLibrary(dllWSHIP6);
#endif
}
else
{
/*
* Hack inserted to deal with problems with numeric IPs.
* FIXME: how will this work in IPv6?
*/
ret->family = AF_INET;
*canonicalname = host;
}
ret->address = ntohl(a);
return ret;
}
void sk_addr_free(SockAddr addr) {
sfree(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. :-)
*/
}
void sk_tcp_close (Socket s);
void sk_tcp_write (Socket s, char *data, int len);
void sk_tcp_write_oob (Socket s, char *data, int len);
char *sk_tcp_socket_error(Socket s);
Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
Plug plug)
{
static struct socket_function_table fn_table = {
sk_tcp_plug,
sk_tcp_close,
sk_tcp_write,
sk_tcp_write_oob,
sk_tcp_flush,
sk_tcp_socket_error
};
SOCKET s;
#ifdef IPV6
SOCKADDR_IN6 a6;
#endif
SOCKADDR_IN a;
DWORD err;
char *errstr;
Actual_Socket ret;
extern char *do_select(SOCKET skt, int startup);
short localport;
/*
* Create Socket structure.
*/
ret = smalloc(sizeof(struct Socket_tag));
ret->fn = &fn_table;
ret->error = NULL;
ret->plug = plug;
ret->head = ret->tail = NULL;
ret->writable = 1; /* to start with */
ret->sending_oob = 0;
/*
* Open socket.
*/
s = socket(addr->family, SOCK_STREAM, 0);
ret->s = s;
if (s == INVALID_SOCKET) {
err = WSAGetLastError();
ret->error = winsock_error_string(err);
return (Socket) ret;
}
ret->oobinline = oobinline;
if (oobinline) {
BOOL b = TRUE;
setsockopt (s, SOL_SOCKET, SO_OOBINLINE, (void *)&b, sizeof(b));
}
/*
* Bind to local address.
*/
if (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 retcode;
#ifdef IPV6
if (addr->family == AF_INET6)
{
memset(&a6,0,sizeof(a6));
a6.sin6_family = AF_INET6;
/*a6.sin6_addr = in6addr_any;*/ /* == 0 */
a6.sin6_port = htons(localport);
}
else
{
#endif
a.sin_family = AF_INET;
a.sin_addr.s_addr = htonl(INADDR_ANY);
a.sin_port = htons(localport);
#ifdef IPV6
}
retcode = bind (s, (addr->family == AF_INET6 ?
(struct sockaddr *)&a6 :
(struct sockaddr *)&a),
(addr->family == AF_INET6 ? sizeof(a6) : sizeof(a)));
#else
retcode = bind (s, (struct sockaddr *)&a, sizeof(a));
#endif
if (retcode != SOCKET_ERROR) {
err = 0;
break; /* done */
} else {
err = 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)
{
ret->error = winsock_error_string(err);
return (Socket) ret;
}
/*
* Connect to remote address.
*/
#ifdef IPV6
if (addr->family == AF_INET6)
{
memset(&a,0,sizeof(a));
a6.sin6_family = AF_INET6;
a6.sin6_port = htons((short)port);
a6.sin6_addr = ((struct sockaddr_in6 *)addr->ai->ai_addr)->sin6_addr;
}
else
{
#endif
a.sin_family = AF_INET;
a.sin_addr.s_addr = htonl(addr->address);
a.sin_port = htons((short)port);
#ifdef IPV6
}
if (connect (s, (addr->family == AF_INET6) ? (struct sockaddr *)&a6 : (struct sockaddr *)&a, (addr->family == AF_INET6) ? sizeof(a6) : sizeof(a)) == SOCKET_ERROR)
#else
if (connect (s, (struct sockaddr *)&a, sizeof(a)) == SOCKET_ERROR)
#endif
{
err = WSAGetLastError();
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) {
ret->error = errstr;
return (Socket) ret;
}
add234(sktree, ret);
return (Socket) ret;
}
static void sk_tcp_close(Socket sock) {
extern char *do_select(SOCKET skt, int startup);
Actual_Socket s = (Actual_Socket) sock;
del234(sktree, s);
do_select(s->s, 0);
closesocket(s->s);
sfree(s);
}
/*
* The function which tries to send on a socket once it's deemed
* writable.
*/
void try_send(Actual_Socket s) {
while (s->head) {
int nsent;
DWORD err;
int len, urgentflag;
if (s->sending_oob) {
urgentflag = MSG_OOB;
len = s->sending_oob;
} else {
urgentflag = 0;
len = s->head->buflen - s->head->bufpos;
}
nsent = send(s->s, s->head->buf + s->head->bufpos, len, urgentflag);
noise_ultralight(nsent);
if (nsent <= 0) {
err = (nsent < 0 ? WSAGetLastError() : 0);
if (err == WSAEWOULDBLOCK) {
/* Perfectly normal: we've sent all we can for the moment. */
s->writable = FALSE;
return;
} else if (nsent == 0 ||
err == WSAECONNABORTED ||
err == WSAECONNRESET) {
/*
* FIXME. This will have to be done better when we
* start managing multiple sockets (e.g. SSH port
* forwarding), because if we get CONNRESET while
* trying to write a particular forwarded socket
* then it isn't necessarily the end of the world.
* Ideally I'd like to pass the error code back to
* somewhere the next select_result() will see it,
* but that might be hard. Perhaps I should pass it
* back to be queued in the Windows front end bit.
*/
fatalbox(winsock_error_string(err));
} else {
fatalbox(winsock_error_string(err));
}
} else {
s->head->bufpos += nsent;
if (s->sending_oob)
s->sending_oob -= nsent;
if (s->head->bufpos >= s->head->buflen) {
struct buffer *tmp = s->head;
s->head = tmp->next;
sfree(tmp);
if (!s->head)
s->tail = NULL;
}
}
}
}
static void sk_tcp_write(Socket sock, char *buf, int len) {
Actual_Socket s = (Actual_Socket) sock;
/*
* Add the data to the buffer list on the socket.
*/
if (s->tail && s->tail->buflen < BUFFER_GRANULE) {
int copylen = min(len, BUFFER_GRANULE - s->tail->buflen);
memcpy(s->tail->buf + s->tail->buflen, buf, copylen);
buf += copylen;
len -= copylen;
s->tail->buflen += copylen;
}
while (len > 0) {
int grainlen = min(len, BUFFER_GRANULE);
struct buffer *newbuf;
newbuf = smalloc(sizeof(struct buffer));
newbuf->bufpos = 0;
newbuf->buflen = grainlen;
memcpy(newbuf->buf, buf, grainlen);
buf += grainlen;
len -= grainlen;
if (s->tail)
s->tail->next = newbuf;
else
s->head = s->tail = newbuf;
newbuf->next = NULL;
s->tail = newbuf;
}
/*
* Now try sending from the start of the buffer list.
*/
if (s->writable)
try_send(s);
}
static void sk_tcp_write_oob(Socket sock, char *buf, int len) {
Actual_Socket s = (Actual_Socket) sock;
/*
* Replace the buffer list on the socket with the data.
*/
if (!s->head) {
s->head = smalloc(sizeof(struct buffer));
} else {
struct buffer *walk = s->head->next;
while (walk) {
struct buffer *tmp = walk;
walk = tmp->next;
sfree(tmp);
}
}
s->head->next = NULL;
s->tail = s->head;
s->head->buflen = len;
memcpy(s->head->buf, buf, len);
/*
* Set the Urgent marker.
*/
s->sending_oob = len;
/*
* Now try sending from the start of the buffer list.
*/
if (s->writable)
try_send(s);
}
int select_result(WPARAM wParam, LPARAM lParam) {
int ret, open;
DWORD err;
char buf[BUFFER_GRANULE];
Actual_Socket s;
u_long atmark;
/* wParam is the socket itself */
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.
*/
return plug_closing (s->plug, winsock_error_string(err), err, 0);
}
noise_ultralight(lParam);
switch (WSAGETSELECTEVENT(lParam)) {
case FD_READ:
/*
* 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;
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 = recv(s->s, buf, sizeof(buf), 0);
noise_ultralight(ret);
if (ret < 0) {
err = 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 = recv(s->s, buf, sizeof(buf), MSG_OOB);
noise_ultralight(ret);
if (ret <= 0) {
fatalbox(ret == 0 ? "Internal networking trouble" :
winsock_error_string(WSAGetLastError()));
} else {
return plug_receive (s->plug, 2, buf, ret);
}
break;
case FD_WRITE:
s->writable = 1;
try_send(s);
break;
case FD_CLOSE:
/* Signal a close on the socket. First read any outstanding data. */
open = 1;
do {
ret = recv(s->s, buf, sizeof(buf), 0);
if (ret < 0) {
err = 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;
}
return 1;
}
/*
* Each socket abstraction contains a `void *' private field in
* which the client can keep state.
*/
void sk_set_private_ptr(Socket sock, void *ptr) {
Actual_Socket s = (Actual_Socket) sock;
s->private_ptr = ptr;
}
void *sk_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.
*/
char *sk_addr_error(SockAddr addr) {
return addr->error;
}
static char *sk_tcp_socket_error(Socket sock) {
Actual_Socket s = (Actual_Socket) sock;
return s->error;
}
/*
* For Plink: enumerate all sockets currently active.
*/
SOCKET first_socket(enum234 *e) {
Actual_Socket s = first234(sktree, e);
return s ? s->s : INVALID_SOCKET;
}
SOCKET next_socket(enum234 *e) {
Actual_Socket s = next234(e);
return s ? s->s : INVALID_SOCKET;
}