xref: /qemu/ui/vnc-auth-vencrypt.c (revision 6402cbbb)
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 
163