diff options
Diffstat (limited to 'libvncclient')
| -rw-r--r-- | libvncclient/rfbproto.c | 75 | ||||
| -rw-r--r-- | libvncclient/tls.c | 227 |
2 files changed, 298 insertions, 4 deletions
diff --git a/libvncclient/rfbproto.c b/libvncclient/rfbproto.c index 1a71f4f..497facb 100644 --- a/libvncclient/rfbproto.c +++ b/libvncclient/rfbproto.c @@ -504,7 +504,7 @@ ReadSupportedSecurityType(rfbClient* client, uint32_t *result, rfbBool subAuth) rfbClientLog("%d) Received security type %d\n", loop, tAuth[loop]); if (flag) continue; if (tAuth[loop]==rfbVncAuth || tAuth[loop]==rfbNoAuth || - (!subAuth && tAuth[loop]==rfbTLS)) + (!subAuth && (tAuth[loop]==rfbTLS || tAuth[loop]==rfbVeNCrypt))) { flag++; authScheme=tAuth[loop]; @@ -569,6 +569,50 @@ HandleVncAuth(rfbClient *client) return TRUE; } +static rfbBool +HandlePlainAuth(rfbClient *client) +{ + uint32_t ulen, ulensw; + uint32_t plen, plensw; + rfbCredential *cred; + + if (!client->GetCredential) + { + rfbClientLog("GetCredential callback is not set.\n"); + return FALSE; + } + cred = client->GetCredential(client, rfbCredentialTypeUser); + if (!cred) + { + rfbClientLog("Reading credential failed\n"); + return FALSE; + } + + ulen = (cred->userCredential.username ? strlen(cred->userCredential.username) : 0); + ulensw = rfbClientSwap32IfLE(ulen); + plen = (cred->userCredential.password ? strlen(cred->userCredential.password) : 0); + plensw = rfbClientSwap32IfLE(plen); + if (!WriteToRFBServer(client, (char *)&ulensw, 4)) return FALSE; + if (!WriteToRFBServer(client, (char *)&plensw, 4)) return FALSE; + if (ulen > 0) + { + if (!WriteToRFBServer(client, cred->userCredential.username, ulen)) return FALSE; + } + if (plen > 0) + { + if (!WriteToRFBServer(client, cred->userCredential.password, plen)) return FALSE; + } + + if (cred->userCredential.username) free(cred->userCredential.username); + if (cred->userCredential.password) free(cred->userCredential.password); + free(cred); + + /* Handle the SecurityResult message */ + if (!rfbHandleAuthResult(client)) return FALSE; + + return TRUE; +} + /* * InitialiseRFBConnection. */ @@ -700,6 +744,35 @@ InitialiseRFBConnection(rfbClient* client) break; + case rfbVeNCrypt: + if (!HandleVeNCryptAuth(client)) return FALSE; + + switch (client->subAuthScheme) { + + case rfbVeNCryptTLSNone: + case rfbVeNCryptX509None: + rfbClientLog("No sub authentication needed\n"); + if (!rfbHandleAuthResult(client)) return FALSE; + break; + + case rfbVeNCryptTLSVNC: + case rfbVeNCryptX509VNC: + if (!HandleVncAuth(client)) return FALSE; + break; + + case rfbVeNCryptTLSPlain: + case rfbVeNCryptX509Plain: + if (!HandlePlainAuth(client)) return FALSE; + break; + + default: + rfbClientLog("Unknown sub authentication scheme from VNC server: %d\n", + client->subAuthScheme); + return FALSE; + } + + break; + default: rfbClientLog("Unknown authentication scheme from VNC server: %d\n", (int)authScheme); diff --git a/libvncclient/tls.c b/libvncclient/tls.c index b8d2d1f..206dbda 100644 --- a/libvncclient/tls.c +++ b/libvncclient/tls.c @@ -168,6 +168,136 @@ HandshakeTLS(rfbClient* client) 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; +} + +static void +FreeX509Credential(rfbCredential *cred) +{ + if (cred->x509Credential.x509CACertFile) free(cred->x509Credential.x509CACertFile); + if (cred->x509Credential.x509CACrlFile) free(cred->x509Credential.x509CACrlFile); + if (cred->x509Credential.x509ClientCertFile) free(cred->x509Credential.x509ClientCertFile); + if (cred->x509Credential.x509ClientKeyFile) free(cred->x509Credential.x509ClientKeyFile); + free(cred); +} + +static gnutls_certificate_credentials_t +CreateX509CertCredential(rfbCredential *cred) +{ + gnutls_certificate_credentials_t x509_cred; + int ret; + + if (!cred->x509Credential.x509CACertFile) + { + rfbClientLog("No CA certificate provided.\n"); + return NULL; + } + + if ((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0) + { + rfbClientLog("Cannot allocate credentials: %s.\n", gnutls_strerror(ret)); + return NULL; + } + if ((ret = gnutls_certificate_set_x509_trust_file(x509_cred, + cred->x509Credential.x509CACertFile, GNUTLS_X509_FMT_PEM)) < 0) + { + rfbClientLog("Cannot load CA credentials: %s.\n", gnutls_strerror(ret)); + gnutls_certificate_free_credentials (x509_cred); + return NULL; + } + if (cred->x509Credential.x509ClientCertFile && cred->x509Credential.x509ClientKeyFile) + { + if ((ret = gnutls_certificate_set_x509_key_file(x509_cred, + cred->x509Credential.x509ClientCertFile, cred->x509Credential.x509ClientKeyFile, + GNUTLS_X509_FMT_PEM)) < 0) + { + rfbClientLog("Cannot load client certificate or key: %s.\n", gnutls_strerror(ret)); + gnutls_certificate_free_credentials (x509_cred); + return NULL; + } + } else + { + rfbClientLog("No client certificate or key provided.\n"); + } + if (cred->x509Credential.x509CACrlFile) + { + if ((ret = gnutls_certificate_set_x509_crl_file(x509_cred, + cred->x509Credential.x509CACrlFile, GNUTLS_X509_FMT_PEM)) < 0) + { + rfbClientLog("Cannot load CRL: %s.\n", gnutls_strerror(ret)); + gnutls_certificate_free_credentials (x509_cred); + return NULL; + } + } else + { + rfbClientLog("No CRL provided.\n"); + } + gnutls_certificate_set_dh_params (x509_cred, rfbDHParams); + return x509_cred; +} + #endif rfbBool @@ -193,17 +323,108 @@ rfbBool HandleVeNCryptAuth(rfbClient* client) { #ifdef LIBVNCSERVER_WITH_CLIENT_TLS + uint8_t major, minor, status; + uint32_t authScheme; + rfbBool anonTLS; + gnutls_certificate_credentials_t x509_cred = NULL; int ret; - if (!InitializeTLS() || !InitializeTLSSession(client, FALSE)) return FALSE; + 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; + } + + x509_cred = CreateX509CertCredential(cred); + FreeX509Credential(cred); + if (!x509_cred) return FALSE; + } - /* TODO: read VeNCrypt version, etc */ - /* TODO: call GetCredential and set to TLS session */ + /* Start up the TLS session */ + if (!InitializeTLSSession(client, anonTLS)) return FALSE; + + if (anonTLS) + { + if (!SetTLSAnonCredential(client)) return FALSE; + } + else + { + 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; #else |