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#include "vnc.h"
#include <libsec.h>
#include <auth.h>
char *serveraddr;
enum
{
VerLen = 12
};
static char version33[VerLen+1] = "RFB 003.003\n";
static char version38[VerLen+1] = "RFB 003.008\n";
static int srvversion;
int
vncsrvhandshake(Vnc *v)
{
char msg[VerLen+1];
strecpy(msg, msg+sizeof msg, version33);
if(verbose)
fprint(2, "server version: %s\n", msg);
vncwrbytes(v, msg, VerLen);
vncflush(v);
vncrdbytes(v, msg, VerLen);
if(verbose)
fprint(2, "client version: %s\n", msg);
return 0;
}
int
vnchandshake(Vnc *v)
{
char msg[VerLen+1];
msg[VerLen] = 0;
vncrdbytes(v, msg, VerLen);
if(strncmp(msg, "RFB 003.", 8) != 0 ||
strncmp(msg, "RFB 003.007\n", VerLen) == 0){
werrstr("bad rfb version \"%s\"", msg);
return -1;
}
if(strncmp(msg, "RFB 003.008\n", VerLen) == 0)
srvversion = 38;
else
srvversion = 33;
if(verbose)
fprint(2, "server version: %s\n", msg);
strcpy(msg, version38);
vncwrbytes(v, msg, VerLen);
vncflush(v);
return 0;
}
ulong
sectype38(Vnc *v)
{
ulong auth, type;
int i, ntypes;
ntypes = vncrdchar(v);
if(ntypes == 0){
werrstr("no security types from server");
return AFailed;
}
/* choose the "most secure" security type */
auth = AFailed;
for(i = 0; i < ntypes; i++){
type = vncrdchar(v);
if(verbose){
fprint(2, "auth type %s\n",
type == AFailed ? "Invalid" :
type == ANoAuth ? "None" :
type == AVncAuth ? "VNC" : "Unknown");
}
if(type > auth && type <= AVncAuth)
auth = type;
}
return auth;
}
int
vncauth(Vnc *v, char *keypattern)
{
char *reason;
uchar chal[VncChalLen];
ulong auth;
if(keypattern == nil)
keypattern = "";
auth = srvversion == 38 ? sectype38(v) : vncrdlong(v);
switch(auth){
default:
werrstr("unknown auth type 0x%lux", auth);
if(verbose)
fprint(2, "unknown auth type 0x%lux\n", auth);
return -1;
case AFailed:
failed:
reason = vncrdstring(v);
werrstr("%s", reason);
if(verbose)
fprint(2, "auth failed: %s\n", reason);
return -1;
case ANoAuth:
if(srvversion == 38){
vncwrchar(v, auth);
vncflush(v);
}
if(verbose)
fprint(2, "no auth needed\n");
break;
case AVncAuth:
if(srvversion == 38){
vncwrchar(v, auth);
vncflush(v);
}
vncrdbytes(v, chal, VncChalLen);
if(auth_respond(chal, VncChalLen, nil, 0, chal, VncChalLen, auth_getkey,
"proto=vnc role=client server=%s %s", serveraddr, keypattern) != VncChalLen){
return -1;
}
vncwrbytes(v, chal, VncChalLen);
vncflush(v);
break;
}
/* in version 3.8 the auth status is always sent, in 3.3 only in AVncAuth */
if(srvversion == 38 || auth == AVncAuth){
auth = vncrdlong(v); /* auth status */
switch(auth){
default:
werrstr("unknown server response 0x%lux", auth);
return -1;
case VncAuthFailed:
if (srvversion == 38)
goto failed;
werrstr("server says authentication failed");
return -1;
case VncAuthTooMany:
werrstr("server says too many tries");
return -1;
case VncAuthOK:
break;
}
}
return 0;
}
int
vncsrvauth(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;
}
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