ui/vnc-auth-vencrypt.c

   1 /*
   2  * QEMU VNC display driver: VeNCrypt authentication setup
   3  *
   4  * Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>
   5  * Copyright (C) 2006 Fabrice Bellard
   6  * Copyright (C) 2009 Red Hat, Inc
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24  * THE SOFTWARE.
  25  */
  26
  27 #include "qemu/osdep.h"
  28 #include "vnc.h"
  29 #include "qemu/main-loop.h"
  30
  31 static void start_auth_vencrypt_subauth(VncState *vs)
  32 {
  33     switch (vs->subauth) {
  34     case VNC_AUTH_VENCRYPT_TLSNONE:
  35     case VNC_AUTH_VENCRYPT_X509NONE:
  36        VNC_DEBUG("Accept TLS auth none\n");
  37        vnc_write_u32(vs, 0); /* Accept auth completion */
  38        start_client_init(vs);
  39        break;
  40
  41     case VNC_AUTH_VENCRYPT_TLSVNC:
  42     case VNC_AUTH_VENCRYPT_X509VNC:
  43        VNC_DEBUG("Start TLS auth VNC\n");
  44        start_auth_vnc(vs);
  45        break;
  46
  47 #ifdef CONFIG_VNC_SASL
  48     case VNC_AUTH_VENCRYPT_TLSSASL:
  49     case VNC_AUTH_VENCRYPT_X509SASL:
  50       VNC_DEBUG("Start TLS auth SASL\n");
  51       start_auth_sasl(vs);
  52       break;
  53 #endif /* CONFIG_VNC_SASL */
  54
  55     default: /* Should not be possible, but just in case */
  56        VNC_DEBUG("Reject subauth %d server bug\n", vs->auth);
  57        vnc_write_u8(vs, 1);
  58        if (vs->minor >= 8) {
  59            static const char err[] = "Unsupported authentication type";
  60            vnc_write_u32(vs, sizeof(err));
  61            vnc_write(vs, err, sizeof(err));
  62        }
  63        vnc_client_error(vs);
  64     }
  65 }
  66
  67 static void vnc_tls_handshake_done(Object *source,
  68                                    Error *err,
  69                                    gpointer user_data)
  70 {
  71     VncState *vs = user_data;
  72
  73     if (err) {
  74         VNC_DEBUG("Handshake failed %s\n",
  75                   error_get_pretty(err));
  76         vnc_client_error(vs);
  77     } else {
  78         vs->ioc_tag = qio_channel_add_watch(
  79             vs->ioc, G_IO_IN | G_IO_OUT, vnc_client_io, vs, NULL);
  80         start_auth_vencrypt_subauth(vs);
  81     }
  82 }
  83
  84
  85 static int protocol_client_vencrypt_auth(VncState *vs, uint8_t *data, size_t len)
  86 {
  87     int auth = read_u32(data, 0);
  88
  89     if (auth != vs->subauth) {
  90         VNC_DEBUG("Rejecting auth %d\n", auth);
  91         vnc_write_u8(vs, 0); /* Reject auth */
  92         vnc_flush(vs);
  93         vnc_client_error(vs);
  94     } else {
  95         Error *err = NULL;
  96         QIOChannelTLS *tls;
  97         VNC_DEBUG("Accepting auth %d, setting up TLS for handshake\n", auth);
  98         vnc_write_u8(vs, 1); /* Accept auth */
  99         vnc_flush(vs);
 100
 101         if (vs->ioc_tag) {
 102             g_source_remove(vs->ioc_tag);
 103             vs->ioc_tag = 0;
 104         }
 105
 106         tls = qio_channel_tls_new_server(
 107             vs->ioc,
 108             vs->vd->tlscreds,
 109             vs->vd->tlsaclname,
 110             &err);
 111         if (!tls) {
 112             VNC_DEBUG("Failed to setup TLS %s\n", error_get_pretty(err));
 113             error_free(err);
 114             vnc_client_error(vs);
 115             return 0;
 116         }
 117
 118         VNC_DEBUG("Start TLS VeNCrypt handshake process\n");
 119         object_unref(OBJECT(vs->ioc));
 120         vs->ioc = QIO_CHANNEL(tls);
 121         vs->tls = qio_channel_tls_get_session(tls);
 122
 123         qio_channel_tls_handshake(tls,
 124                                   vnc_tls_handshake_done,
 125                                   vs,
 126                                   NULL);
 127     }
 128     return 0;
 129 }
 130
 131 static int protocol_client_vencrypt_init(VncState *vs, uint8_t *data, size_t len)
 132 {
 133     if (data[0] != 0 ||
 134         data[1] != 2) {
 135         VNC_DEBUG("Unsupported VeNCrypt protocol %d.%d\n", (int)data[0], (int)data[1]);
 136         vnc_write_u8(vs, 1); /* Reject version */
 137         vnc_flush(vs);
 138         vnc_client_error(vs);
 139     } else {
 140         VNC_DEBUG("Sending allowed auth %d\n", vs->subauth);
 141         vnc_write_u8(vs, 0); /* Accept version */
 142         vnc_write_u8(vs, 1); /* Number of sub-auths */
 143         vnc_write_u32(vs, vs->subauth); /* The supported auth */
 144         vnc_flush(vs);
 145         vnc_read_when(vs, protocol_client_vencrypt_auth, 4);
 146     }
 147     return 0;
 148 }
 149
 150
 151 void start_auth_vencrypt(VncState *vs)
 152 {
 153     /* Send VeNCrypt version 0.2 */
 154     vnc_write_u8(vs, 0);
 155     vnc_write_u8(vs, 2);
 156
 157     vnc_read_when(vs, protocol_client_vencrypt_init, 2);
 158 }
 159