Bool SendSetEncodings()
{
char buf[sz_rfbSetEncodingsMsg + MAX_ENCODINGS * 4];
rfbSetEncodingsMsg *se = (rfbSetEncodingsMsg *)buf;
CARD32 *encs = (CARD32 *)(&buf[sz_rfbSetEncodingsMsg]);
int len = 0;
int i;
Bool requestCompressLevel = False;
Bool requestQualityLevel = False;
Bool requestLastRectEncoding = False;
se->type = rfbSetEncodings;
se->nEncodings = 0;
if (appData.encodingsString) {
char *encStr = appData.encodingsString;
int encStrLen;
do {
char *nextEncStr = strchr(encStr, ' ');
if (nextEncStr) {
encStrLen = nextEncStr - encStr;
nextEncStr++;
} else {
encStrLen = strlen(encStr);
}
if (strncasecmp(encStr,"raw",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingRaw);
} else if (strncasecmp(encStr,"copyrect",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingCopyRect);
} else if (strncasecmp(encStr,"tight",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingTight);
requestLastRectEncoding = True;
if (appData.compressLevel >= 0 && appData.compressLevel <= 9)
requestCompressLevel = True;
if (appData.enableJPEG)
requestQualityLevel = True;
} else if (strncasecmp(encStr,"hextile",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingHextile);
} else if (strncasecmp(encStr,"zlib",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingZlib);
if (appData.compressLevel >= 0 && appData.compressLevel <= 9)
requestCompressLevel = True;
} else if (strncasecmp(encStr,"corre",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingCoRRE);
} else if (strncasecmp(encStr,"rre",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingRRE);
} else if (strncasecmp(encStr,"zrle",encStrLen) == 0) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingZRLE);
} else {
fprintf(stderr,"Unknown encoding '%.*s'\n",encStrLen,encStr);
}
encStr = nextEncStr;
} while (encStr && se->nEncodings < MAX_ENCODINGS);
if (se->nEncodings < MAX_ENCODINGS && requestCompressLevel) {
encs[se->nEncodings++] = Swap32IfLE(appData.compressLevel +
rfbEncodingCompressLevel0);
}
if (se->nEncodings < MAX_ENCODINGS && requestQualityLevel) {
if (appData.qualityLevel < 0 || appData.qualityLevel > 9)
appData.qualityLevel = 5;
encs[se->nEncodings++] = Swap32IfLE(appData.qualityLevel +
rfbEncodingQualityLevel0);
}
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingXCursor);
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingRichCursor);
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingPointerPos);
if (se->nEncodings < MAX_ENCODINGS && requestLastRectEncoding) {
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingLastRect);
}
} else {
if (sameMachine) {
if (!tunnelSpecified) {
if (!appData.quiet) {
fprintf(stderr,"Same machine: preferring raw encoding\n");
}
currentEncoding = rfbEncodingRaw;
} else {
if (!appData.quiet) {
fprintf(stderr,"Tunneling active: preferring tight encoding\n");
}
currentEncoding = rfbEncodingTight;
}
}
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingLastRect);
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingCopyRect);
encs[se->nEncodings++] = Swap32IfLE(currentEncoding);
for (i = 0; i < NUM_SUPPORTED_ENCODINGS; i++) {
if (supportedEncodings[i] != currentEncoding)
encs[se->nEncodings++] = Swap32IfLE(supportedEncodings[i]);
}
if (appData.compressLevel >= 0 && appData.compressLevel <= 9) {
encs[se->nEncodings++] = Swap32IfLE(appData.compressLevel +
rfbEncodingCompressLevel0);
} else if (!tunnelSpecified) {
/* If -tunnel option was provided, we assume that server machine is
not in the local network so we use default compression level for
tight encoding instead of fast compression. Thus we are
requesting level 1 compression only if tunneling is not used. */
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingCompressLevel1);
}
if (appData.enableJPEG) {
if (appData.qualityLevel < 0 || appData.qualityLevel > 9)
appData.qualityLevel = 5;
encs[se->nEncodings++] = Swap32IfLE(appData.qualityLevel +
rfbEncodingQualityLevel0);
}
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingXCursor);
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingRichCursor);
if (se->nEncodings < MAX_ENCODINGS)
encs[se->nEncodings++] = Swap32IfLE(rfbEncodingPointerPos);
}
len = sz_rfbSetEncodingsMsg + se->nEncodings * 4;
se->nEncodings = Swap16IfLE(se->nEncodings);
return WriteToRFBServer(buf, len);
}
rfbBool
HandleVeNCryptAuth(rfbClient* client)
{
uint8_t major, minor, status;
uint32_t authScheme;
rfbBool anonTLS;
// gnutls_certificate_credentials_t x509_cred = NULL;
int ret;
if (!InitializeTLS()) return FALSE;
/* Read VeNCrypt version */
if (!ReadFromRFBServer(client, (char *)&major, 1) ||
!ReadFromRFBServer(client, (char *)&minor, 1))
{
return FALSE;
}
rfbClientLog("Got VeNCrypt version %d.%d from server.\n", (int)major, (int)minor);
if (major != 0 && minor != 2)
{
rfbClientLog("Unsupported VeNCrypt version.\n");
return FALSE;
}
if (!WriteToRFBServer(client, (char *)&major, 1) ||
!WriteToRFBServer(client, (char *)&minor, 1) ||
!ReadFromRFBServer(client, (char *)&status, 1))
{
return FALSE;
}
if (status != 0)
{
rfbClientLog("Server refused VeNCrypt version %d.%d.\n", (int)major, (int)minor);
return FALSE;
}
if (!ReadVeNCryptSecurityType(client, &authScheme)) return FALSE;
if (!ReadFromRFBServer(client, (char *)&status, 1) || status != 1)
{
rfbClientLog("Server refused VeNCrypt authentication %d (%d).\n", authScheme, (int)status);
return FALSE;
}
client->subAuthScheme = authScheme;
/* Some VeNCrypt security types are anonymous TLS, others are X509 */
switch (authScheme)
{
case rfbVeNCryptTLSNone:
case rfbVeNCryptTLSVNC:
case rfbVeNCryptTLSPlain:
anonTLS = TRUE;
break;
default:
anonTLS = FALSE;
break;
}
/* Get X509 Credentials if it's not anonymous */
if (!anonTLS)
{
rfbCredential *cred;
if (!client->GetCredential)
{
rfbClientLog("GetCredential callback is not set.\n");
return FALSE;
}
cred = client->GetCredential(client, rfbCredentialTypeX509);
if (!cred)
{
rfbClientLog("Reading credential failed\n");
return FALSE;
}
/* TODO: don't just ignore this
x509_cred = CreateX509CertCredential(cred);
FreeX509Credential(cred);
if (!x509_cred) return FALSE; */
}
/* Start up the TLS session */
if (!InitializeTLSSession(client, anonTLS)) return FALSE;
if (anonTLS)
{
if (!SetTLSAnonCredential(client)) return FALSE;
}
else
{
/* TODO: don't just ignore this
if ((ret = gnutls_credentials_set(client->tlsSession, GNUTLS_CRD_CERTIFICATE, x509_cred)) < 0)
{
rfbClientLog("Cannot set x509 credential: %s.\n", gnutls_strerror(ret));
FreeTLS(client); */
return FALSE;
// }
}
if (!HandshakeTLS(client)) return FALSE;
/* TODO: validate certificate */
/* We are done here. The caller should continue with client->subAuthScheme
* to do actual sub authentication.
*/
return TRUE;
}
Bool
InitialiseRFBConnection()
{
rfbProtocolVersionMsg pv;
int major,minor;
CARD32 authScheme, reasonLen, authResult;
char *reason;
CARD8 challenge[CHALLENGESIZE];
char *passwd;
int i;
rfbClientInitMsg ci;
if (!ReadFromRFBServer(pv, sz_rfbProtocolVersionMsg)) return False;
pv[sz_rfbProtocolVersionMsg] = 0;
if (sscanf(pv,rfbProtocolVersionFormat,&major,&minor) != 2) {
fprintf(stderr,"Not a valid VNC server\n");
return False;
}
if (!appData.quiet) {
fprintf(stderr,"VNC server supports protocol version %d.%d (viewer %d.%d)\n",
major, minor, rfbProtocolMajorVersion, rfbProtocolMinorVersion);
}
major = rfbProtocolMajorVersion;
minor = rfbProtocolMinorVersion;
sprintf(pv,rfbProtocolVersionFormat,major,minor);
if (!WriteToRFBServer(pv, sz_rfbProtocolVersionMsg)) return False;
if (!ReadFromRFBServer((char *)&authScheme, 4)) return False;
authScheme = Swap32IfLE(authScheme);
switch (authScheme) {
case rfbConnFailed:
if (!ReadFromRFBServer((char *)&reasonLen, 4)) return False;
reasonLen = Swap32IfLE(reasonLen);
reason = malloc(reasonLen);
if (!ReadFromRFBServer(reason, reasonLen)) return False;
fprintf(stderr,"VNC connection failed: %.*s\n",(int)reasonLen, reason);
return False;
case rfbNoAuth:
if (!appData.quiet) {
fprintf(stderr,"No authentication needed\n");
}
break;
case rfbVncAuth:
if (!ReadFromRFBServer((char *)challenge, CHALLENGESIZE)) return False;
if (appData.passwordFile) {
passwd = vncDecryptPasswdFromFile(appData.passwordFile);
if (!passwd) {
fprintf(stderr,"Cannot read valid password from file \"%s\"\n",
appData.passwordFile);
return False;
} /* added this to read the command line password */
} else if (appData.tpass) {
passwd = appData.tpass;
} else {
passwd = getpass("Password: "******"Reading password failed\n");
return False;
}
if (strlen(passwd) > 8) {
passwd[8] = '\0';
}
vncEncryptBytes(challenge, passwd);
/* Lose the password from memory */
for (i = strlen(passwd); i >= 0; i--) {
passwd[i] = '\0';
}
if (!WriteToRFBServer((char *)challenge, CHALLENGESIZE)) return False;
if (!ReadFromRFBServer((char *)&authResult, 4)) return False;
authResult = Swap32IfLE(authResult);
switch (authResult) {
case rfbVncAuthOK:
if (!appData.quiet) {
fprintf(stderr,"VNC authentication succeeded\n");
}
break;
case rfbVncAuthFailed:
fprintf(stderr,"VNC authentication failed\n");
return False;
case rfbVncAuthTooMany:
fprintf(stderr,"VNC authentication failed - too many tries\n");
return False;
default:
fprintf(stderr,"Unknown VNC authentication result: %d\n",
(int)authResult);
return False;
}
break;
default:
fprintf(stderr,"Unknown authentication scheme from VNC server: %d\n",
(int)authScheme);
return False;
}
ci.shared = 1;
if (!WriteToRFBServer((char *)&ci, sz_rfbClientInitMsg)) return False;
if (!ReadFromRFBServer((char *)&si, sz_rfbServerInitMsg)) return False;
si.framebufferWidth = Swap16IfLE(si.framebufferWidth);
si.framebufferHeight = Swap16IfLE(si.framebufferHeight);
si.format.redMax = Swap16IfLE(si.format.redMax);
si.format.greenMax = Swap16IfLE(si.format.greenMax);
si.format.blueMax = Swap16IfLE(si.format.blueMax);
si.nameLength = Swap32IfLE(si.nameLength);
desktopName = malloc(si.nameLength + 1);
if (!desktopName) {
fprintf(stderr, "Error allocating memory for desktop name, %lu bytes\n",
(unsigned long)si.nameLength);
return False;
}
if (!ReadFromRFBServer(desktopName, si.nameLength)) return False;
desktopName[si.nameLength] = 0;
if (!appData.quiet) {
fprintf(stderr,"Desktop name \"%s\"\n",desktopName);
fprintf(stderr,"Connected to VNC server, using protocol version %d.%d\n",
rfbProtocolMajorVersion, rfbProtocolMinorVersion);
fprintf(stderr,"VNC server default format:\n");
PrintPixelFormat(&si.format);
}
return True;
}
/* VeNCrypt sub auth. 1 byte auth count, followed by count * 4 byte integers */
static rfbBool
ReadVeNCryptSecurityType(rfbClient* client, uint32_t *result)
{
uint8_t count=0;
uint8_t loop=0;
uint8_t flag=0;
uint32_t tAuth[256], t;
char buf1[500],buf2[10];
uint32_t authScheme;
if (!ReadFromRFBServer(client, (char *)&count, 1)) return FALSE;
if (count==0)
{
rfbClientLog("List of security types is ZERO. Giving up.\n");
return FALSE;
}
if (count>sizeof(tAuth))
{
rfbClientLog("%d security types are too many; maximum is %d\n", count, sizeof(tAuth));
return FALSE;
}
rfbClientLog("We have %d security types to read\n", count);
authScheme=0;
/* now, we have a list of available security types to read ( uint8_t[] ) */
for (loop=0;loop<count;loop++)
{
if (!ReadFromRFBServer(client, (char *)&tAuth[loop], 4)) return FALSE;
t=rfbClientSwap32IfLE(tAuth[loop]);
rfbClientLog("%d) Received security type %d\n", loop, t);
if (flag) continue;
if (t==rfbVeNCryptTLSNone ||
t==rfbVeNCryptTLSVNC ||
t==rfbVeNCryptTLSPlain ||
t==rfbVeNCryptX509None ||
t==rfbVeNCryptX509VNC ||
t==rfbVeNCryptX509Plain)
{
flag++;
authScheme=t;
rfbClientLog("Selecting security type %d (%d/%d in the list)\n", authScheme, loop, count);
/* send back 4 bytes (in original byte order!) indicating which security type to use */
if (!WriteToRFBServer(client, (char *)&tAuth[loop], 4)) return FALSE;
}
tAuth[loop]=t;
}
if (authScheme==0)
{
memset(buf1, 0, sizeof(buf1));
for (loop=0;loop<count;loop++)
{
if (strlen(buf1)>=sizeof(buf1)-1) break;
snprintf(buf2, sizeof(buf2), (loop>0 ? ", %d" : "%d"), (int)tAuth[loop]);
strncat(buf1, buf2, sizeof(buf1)-strlen(buf1)-1);
}
rfbClientLog("Unknown VeNCrypt authentication scheme from VNC server: %s\n",
buf1);
return FALSE;
}
*result = authScheme;
return TRUE;
}
