/* * QEMU VNC display driver: VeNCrypt authentication setup * * Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws> * Copyright (C) 2006 Fabrice Bellard * Copyright (C) 2009 Red Hat, Inc * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "vnc.h" static void start_auth_vencrypt_subauth(VncState *vs) { switch (vs->subauth) { case VNC_AUTH_VENCRYPT_TLSNONE: case VNC_AUTH_VENCRYPT_X509NONE: VNC_DEBUG("Accept TLS auth none\n"); vnc_write_u32(vs, 0); /* Accept auth completion */ start_client_init(vs); break; case VNC_AUTH_VENCRYPT_TLSVNC: case VNC_AUTH_VENCRYPT_X509VNC: VNC_DEBUG("Start TLS auth VNC\n"); start_auth_vnc(vs); break; #ifdef CONFIG_VNC_SASL case VNC_AUTH_VENCRYPT_TLSSASL: case VNC_AUTH_VENCRYPT_X509SASL: VNC_DEBUG("Start TLS auth SASL\n"); return start_auth_sasl(vs); #endif /* CONFIG_VNC_SASL */ default: /* Should not be possible, but just in case */ VNC_DEBUG("Reject subauth %d server bug\n", vs->auth); vnc_write_u8(vs, 1); if (vs->minor >= 8) { static const char err[] = "Unsupported authentication type"; vnc_write_u32(vs, sizeof(err)); vnc_write(vs, err, sizeof(err)); } vnc_client_error(vs); } } static void vnc_tls_handshake_io(void *opaque); static int vnc_start_vencrypt_handshake(struct VncState *vs) { int ret; if ((ret = gnutls_handshake(vs->tls.session)) < 0) { if (!gnutls_error_is_fatal(ret)) { VNC_DEBUG("Handshake interrupted (blocking)\n"); if (!gnutls_record_get_direction(vs->tls.session)) qemu_set_fd_handler(vs->csock, vnc_tls_handshake_io, NULL, vs); else qemu_set_fd_handler(vs->csock, NULL, vnc_tls_handshake_io, vs); return 0; } VNC_DEBUG("Handshake failed %s\n", gnutls_strerror(ret)); vnc_client_error(vs); return -1; } if (vs->vd->tls.x509verify) { if (vnc_tls_validate_certificate(vs) < 0) { VNC_DEBUG("Client verification failed\n"); vnc_client_error(vs); return -1; } else { VNC_DEBUG("Client verification passed\n"); } } VNC_DEBUG("Handshake done, switching to TLS data mode\n"); vs->tls.wiremode = VNC_WIREMODE_TLS; qemu_set_fd_handler2(vs->csock, NULL, vnc_client_read, vnc_client_write, vs); start_auth_vencrypt_subauth(vs); return 0; } static void vnc_tls_handshake_io(void *opaque) { struct VncState *vs = (struct VncState *)opaque; VNC_DEBUG("Handshake IO continue\n"); vnc_start_vencrypt_handshake(vs); } #define NEED_X509_AUTH(vs) \ ((vs)->subauth == VNC_AUTH_VENCRYPT_X509NONE || \ (vs)->subauth == VNC_AUTH_VENCRYPT_X509VNC || \ (vs)->subauth == VNC_AUTH_VENCRYPT_X509PLAIN || \ (vs)->subauth == VNC_AUTH_VENCRYPT_X509SASL) static int protocol_client_vencrypt_auth(VncState *vs, uint8_t *data, size_t len) { int auth = read_u32(data, 0); if (auth != vs->subauth) { VNC_DEBUG("Rejecting auth %d\n", auth); vnc_write_u8(vs, 0); /* Reject auth */ vnc_flush(vs); vnc_client_error(vs); } else { VNC_DEBUG("Accepting auth %d, setting up TLS for handshake\n", auth); vnc_write_u8(vs, 1); /* Accept auth */ vnc_flush(vs); if (vnc_tls_client_setup(vs, NEED_X509_AUTH(vs)) < 0) { VNC_DEBUG("Failed to setup TLS\n"); return 0; } VNC_DEBUG("Start TLS VeNCrypt handshake process\n"); if (vnc_start_vencrypt_handshake(vs) < 0) { VNC_DEBUG("Failed to start TLS handshake\n"); return 0; } } return 0; } static int protocol_client_vencrypt_init(VncState *vs, uint8_t *data, size_t len) { if (data[0] != 0 || data[1] != 2) { VNC_DEBUG("Unsupported VeNCrypt protocol %d.%d\n", (int)data[0], (int)data[1]); vnc_write_u8(vs, 1); /* Reject version */ vnc_flush(vs); vnc_client_error(vs); } else { VNC_DEBUG("Sending allowed auth %d\n", vs->subauth); vnc_write_u8(vs, 0); /* Accept version */ vnc_write_u8(vs, 1); /* Number of sub-auths */ vnc_write_u32(vs, vs->subauth); /* The supported auth */ vnc_flush(vs); vnc_read_when(vs, protocol_client_vencrypt_auth, 4); } return 0; } void start_auth_vencrypt(VncState *vs) { /* Send VeNCrypt version 0.2 */ vnc_write_u8(vs, 0); vnc_write_u8(vs, 2); vnc_read_when(vs, protocol_client_vencrypt_init, 2); }