/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include "vnc.h"#include <libsec.h>#include <auth.h> char *serveraddr; /* * Encrypt n bytes using the password * as key, padded with zeros to 8 bytes. */enum{	VerLen	= 12}; static char version[VerLen+1] = "RFB 003.003\n"; static uchar tab[256]; /* VNC reverses the bits of each byte before using as a des key */static voidmktab(void){	int i, j, k;	static int once; 	if(once)		return;	once = 1; 	for(i=0; i<256; i++){		j=i;		tab[i] = 0;		for(k=0; k<8; k++){			tab[i] = (tab[i]<<1) | (j&1);			j >>= 1;		}	}} static voidvncencrypt(uchar *buf, int n, char *pw){	uchar *p;	uchar key[9];	DESstate s; 	mktab();	memset(key, 0, sizeof key);	strncpy((char*)key, pw, 8);	for(p=key; *p; p++)		*p = tab[*p]; 	setupDESstate(&s, key, nil);	desECBencrypt(buf, n, &s);} static intreadln(char *prompt, char *line, int len){	char *p;	int fd, ctl, n, nr; 	fd = open("/dev/cons", ORDWR);	if(fd < 0)		sysfatal("couldn't open cons");	ctl = open("/dev/consctl", OWRITE);	if(ctl < 0)		sysfatal("couldn't open consctl");	write(ctl, "rawon", 5);	fprint(fd, "%s", prompt);	nr = 0;	p = line;	for(;;){		n = read(fd, p, 1);		if(n < 0){			close(fd);			close(ctl);			return -1;		}		if(n == 0 || *p == '\n' || *p == '\r'){			*p = '\0';			write(fd, "\n", 1);			close(fd);			close(ctl);			return nr;		}		if(*p == '\b'){			if(nr > 0){				nr--;				p--;			}		}else if(*p == 21){		/* cntrl-u */			fprint(fd, "\n%s", prompt);			nr = 0;			p = line;		}else{			nr++;			p++;		}		if(nr == len){			fprint(fd, "line too long; try again\n%s", prompt);			nr = 0;			p = line;		}	}} intvncsrvhandshake(Vnc *v){	char msg[VerLen+1]; 	strecpy(msg, msg+sizeof msg, version);	if(verbose)		fprint(2, "server version: %s", msg);	vncwrbytes(v, msg, VerLen);	vncflush(v); 	vncrdbytes(v, msg, VerLen);	if(verbose)		fprint(2, "client version: %s", msg);	return 0;} intvnchandshake(Vnc *v){	char msg[VerLen+1]; 	msg[VerLen] = 0;	vncrdbytes(v, msg, VerLen);	if(strncmp(msg, "RFB ", 4) != 0){		werrstr("bad rfb version \"%s\"", msg);		return -1;	}	if(verbose)		fprint(2, "server version: %s", msg);	strcpy(msg, version);	vncwrbytes(v, msg, VerLen);	vncflush(v);	return 0;} intvncauth(Vnc *v, char *keypattern){	char pw[128], *reason;	uchar chal[VncChalLen];	ulong auth;	char *p, *server; 	if(keypattern == nil)		keypattern = "";	auth = vncrdlong(v);	switch(auth){	default:		werrstr("unknown auth type 0x%lux", auth);		if(verbose)			fprint(2, "unknown auth type 0x%lux", auth);		return -1; 	case AFailed:		reason = vncrdstring(v);		werrstr("%s", reason);		if(verbose)			fprint(2, "auth failed: %s\n", reason);		return -1; 	case ANoAuth:		if(verbose)			fprint(2, "no auth needed");		break; 	case AVncAuth:		vncrdbytes(v, chal, VncChalLen);		server = strdup(serveraddr);		p = strrchr(server, ':');		if(p)			*p = 0;		if(auth_respond(chal, VncChalLen, nil, 0, chal, VncChalLen, auth_getkey,			"proto=vnc role=client server=%s %s", server, keypattern) != VncChalLen){			/* BUG This is for drawterm users who don't start their own factotums */			readln("password: ", pw, sizeof(pw));			vncencrypt(chal, VncChalLen, pw);			memset(pw, 0, sizeof pw);		}		free(server);		vncwrbytes(v, chal, VncChalLen);		vncflush(v); 		auth = vncrdlong(v);		switch(auth){		default:			werrstr("unknown server response 0x%lux", auth);			return -1;		case VncAuthFailed:			werrstr("server says authentication failed");			return -1;		case VncAuthTooMany:			werrstr("server says too many tries");			return -1;		case VncAuthOK:			break;		}		break;	}	return 0;} intvncsrvauth(Vnc *v){	Chalstate *c;	AuthInfo *ai; 	if((c = auth_challenge("proto=vnc role=server user=%q", getuser()))==nil)		sysfatal("vncchal: %r");	if(c->nchal != VncChalLen)		sysfatal("vncchal got %d bytes wanted %d", c->nchal, VncChalLen);	vncwrlong(v, AVncAuth);	vncwrbytes(v, c->chal, VncChalLen);	vncflush(v); 	vncrdbytes(v, c->chal, VncChalLen);	c->resp = c->chal;	c->nresp = VncChalLen;	ai = auth_response(c);	auth_freechal(c);	if(ai == nil){		fprint(2, "vnc auth failed: server factotum: %r\n");		vncwrlong(v, VncAuthFailed);		vncflush(v);		return -1;	}	auth_freeAI(ai);	vncwrlong(v, VncAuthOK);	vncflush(v); 	return 0;}