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 "qapi/error.h"
  30 #include "qemu/main-loop.h"
  31
  32 static void start_auth_vencrypt_subauth(VncState *vs)
  33 {
  34     switch (vs->subauth) {
  35     case VNC_AUTH_VENCRYPT_TLSNONE:
  36     case VNC_AUTH_VENCRYPT_X509NONE:
  37        VNC_DEBUG("Accept TLS auth none\n");
  38        vnc_write_u32(vs, 0); /* Accept auth completion */
  39        start_client_init(vs);
  40        break;
  41
  42     case VNC_AUTH_VENCRYPT_TLSVNC:
  43     case VNC_AUTH_VENCRYPT_X509VNC:
  44        VNC_DEBUG("Start TLS auth VNC\n");
  45        start_auth_vnc(vs);
  46        break;
  47
  48 #ifdef CONFIG_VNC_SASL
  49     case VNC_AUTH_VENCRYPT_TLSSASL:
  50     case VNC_AUTH_VENCRYPT_X509SASL:
  51       VNC_DEBUG("Start TLS auth SASL\n");
  52       start_auth_sasl(vs);
  53       break;
  54 #endif /* CONFIG_VNC_SASL */
  55
  56     default: /* Should not be possible, but just in case */
  57        VNC_DEBUG("Reject subauth %d server bug\n", vs->auth);
  58        vnc_write_u8(vs, 1);
  59        if (vs->minor >= 8) {
  60            static const char err[] = "Unsupported authentication type";
  61            vnc_write_u32(vs, sizeof(err));
  62            vnc_write(vs, err, sizeof(err));
  63        }
  64        vnc_client_error(vs);
  65     }
  66 }
  67
  68 static void vnc_tls_handshake_done(QIOTask *task,
  69                                    gpointer user_data)
  70 {
  71     VncState *vs = user_data;
  72     Error *err = NULL;
  73
  74     if (qio_task_propagate_error(task, &err)) {
  75         VNC_DEBUG("Handshake failed %s\n",
  76                   error_get_pretty(err));
  77         vnc_client_error(vs);
  78         error_free(err);
  79     } else {
  80         vs->ioc_tag = qio_channel_add_watch(
  81             vs->ioc, G_IO_IN | G_IO_OUT, vnc_client_io, vs, NULL);
  82         start_auth_vencrypt_subauth(vs);
  83     }
  84 }
  85
  86
  87 static int protocol_client_vencrypt_auth(VncState *vs, uint8_t *data, size_t len)
  88 {
  89     int auth = read_u32(data, 0);
  90
  91     if (auth != vs->subauth) {
  92         VNC_DEBUG("Rejecting auth %d\n", auth);
  93         vnc_write_u8(vs, 0); /* Reject auth */
  94         vnc_flush(vs);
  95         vnc_client_error(vs);
  96     } else {
  97         Error *err = NULL;
  98         QIOChannelTLS *tls;
  99         VNC_DEBUG("Accepting auth %d, setting up TLS for handshake\n", auth);
 100         vnc_write_u8(vs, 1); /* Accept auth */
 101         vnc_flush(vs);
 102
 103         if (vs->ioc_tag) {
 104             g_source_remove(vs->ioc_tag);
 105             vs->ioc_tag = 0;
 106         }
 107
 108         tls = qio_channel_tls_new_server(
 109             vs->ioc,
 110             vs->vd->tlscreds,
 111             vs->vd->tlsaclname,
 112             &err);
 113         if (!tls) {
 114             VNC_DEBUG("Failed to setup TLS %s\n", error_get_pretty(err));
 115             error_free(err);
 116             vnc_client_error(vs);
 117             return 0;
 118         }
 119
 120         qio_channel_set_name(QIO_CHANNEL(tls), "vnc-server-tls");
 121         VNC_DEBUG("Start TLS VeNCrypt handshake process\n");
 122         object_unref(OBJECT(vs->ioc));
 123         vs->ioc = QIO_CHANNEL(tls);
 124         vs->tls = qio_channel_tls_get_session(tls);
 125
 126         qio_channel_tls_handshake(tls,
 127                                   vnc_tls_handshake_done,
 128                                   vs,
 129                                   NULL);
 130     }
 131     return 0;
 132 }
 133
 134 static int protocol_client_vencrypt_init(VncState *vs, uint8_t *data, size_t len)
 135 {
 136     if (data[0] != 0 ||
 137         data[1] != 2) {
 138         VNC_DEBUG("Unsupported VeNCrypt protocol %d.%d\n", (int)data[0], (int)data[1]);
 139         vnc_write_u8(vs, 1); /* Reject version */
 140         vnc_flush(vs);
 141         vnc_client_error(vs);
 142     } else {
 143         VNC_DEBUG("Sending allowed auth %d\n", vs->subauth);
 144         vnc_write_u8(vs, 0); /* Accept version */
 145         vnc_write_u8(vs, 1); /* Number of sub-auths */
 146         vnc_write_u32(vs, vs->subauth); /* The supported auth */
 147         vnc_flush(vs);
 148         vnc_read_when(vs, protocol_client_vencrypt_auth, 4);
 149     }
 150     return 0;
 151 }
 152
 153
 154 void start_auth_vencrypt(VncState *vs)
 155 {
 156     /* Send VeNCrypt version 0.2 */
 157     vnc_write_u8(vs, 0);
 158     vnc_write_u8(vs, 2);
 159
 160     vnc_read_when(vs, protocol_client_vencrypt_init, 2);
 161 }
 162