1 /*
2 * QEMU TDX Quote Generation Support
3 *
4 * Copyright (c) 2025 Intel Corporation
5 *
6 * Author:
7 * Xiaoyao Li <xiaoyao.li@intel.com>
8 *
9 * SPDX-License-Identifier: GPL-2.0-or-later
10 */
11
12 #include "qemu/osdep.h"
13 #include "qemu/error-report.h"
14 #include "qapi/error.h"
15 #include "qapi/qapi-visit-sockets.h"
16
17 #include "tdx-quote-generator.h"
18
19 #define QGS_MSG_LIB_MAJOR_VER 1
20 #define QGS_MSG_LIB_MINOR_VER 1
21
22 typedef enum _qgs_msg_type_t {
23 GET_QUOTE_REQ = 0,
24 GET_QUOTE_RESP = 1,
25 GET_COLLATERAL_REQ = 2,
26 GET_COLLATERAL_RESP = 3,
27 GET_PLATFORM_INFO_REQ = 4,
28 GET_PLATFORM_INFO_RESP = 5,
29 QGS_MSG_TYPE_MAX
30 } qgs_msg_type_t;
31
32 typedef struct _qgs_msg_header_t {
33 uint16_t major_version;
34 uint16_t minor_version;
35 uint32_t type;
36 uint32_t size; // size of the whole message, include this header, in byte
37 uint32_t error_code; // used in response only
38 } qgs_msg_header_t;
39
40 typedef struct _qgs_msg_get_quote_req_t {
41 qgs_msg_header_t header; // header.type = GET_QUOTE_REQ
42 uint32_t report_size; // cannot be 0
43 uint32_t id_list_size; // length of id_list, in byte, can be 0
44 } qgs_msg_get_quote_req_t;
45
46 typedef struct _qgs_msg_get_quote_resp_s {
47 qgs_msg_header_t header; // header.type = GET_QUOTE_RESP
48 uint32_t selected_id_size; // can be 0 in case only one id is sent in request
49 uint32_t quote_size; // length of quote_data, in byte
50 uint8_t id_quote[]; // selected id followed by quote
51 } qgs_msg_get_quote_resp_t;
52
53 #define HEADER_SIZE 4
54
decode_header(const char * buf,size_t len)55 static uint32_t decode_header(const char *buf, size_t len) {
56 if (len < HEADER_SIZE) {
57 return 0;
58 }
59 uint32_t msg_size = 0;
60 for (uint32_t i = 0; i < HEADER_SIZE; ++i) {
61 msg_size = msg_size * 256 + (buf[i] & 0xFF);
62 }
63 return msg_size;
64 }
65
encode_header(char * buf,size_t len,uint32_t size)66 static void encode_header(char *buf, size_t len, uint32_t size) {
67 assert(len >= HEADER_SIZE);
68 buf[0] = ((size >> 24) & 0xFF);
69 buf[1] = ((size >> 16) & 0xFF);
70 buf[2] = ((size >> 8) & 0xFF);
71 buf[3] = (size & 0xFF);
72 }
73
tdx_generate_quote_cleanup(TdxGenerateQuoteTask * task)74 static void tdx_generate_quote_cleanup(TdxGenerateQuoteTask *task)
75 {
76 timer_del(&task->timer);
77
78 g_source_remove(task->watch);
79 qio_channel_close(QIO_CHANNEL(task->sioc), NULL);
80 object_unref(OBJECT(task->sioc));
81
82 task->completion(task);
83 }
84
tdx_get_quote_read(QIOChannel * ioc,GIOCondition condition,gpointer opaque)85 static gboolean tdx_get_quote_read(QIOChannel *ioc, GIOCondition condition,
86 gpointer opaque)
87 {
88 TdxGenerateQuoteTask *task = opaque;
89 Error *err = NULL;
90 int ret;
91
92 ret = qio_channel_read(ioc, task->receive_buf + task->receive_buf_received,
93 task->payload_len - task->receive_buf_received, &err);
94 if (ret < 0) {
95 if (ret == QIO_CHANNEL_ERR_BLOCK) {
96 return G_SOURCE_CONTINUE;
97 } else {
98 error_report_err(err);
99 task->status_code = TDX_VP_GET_QUOTE_ERROR;
100 goto end;
101 }
102 }
103
104 if (ret == 0) {
105 error_report("End of file before reply received");
106 task->status_code = TDX_VP_GET_QUOTE_ERROR;
107 goto end;
108 }
109
110 task->receive_buf_received += ret;
111 if (task->receive_buf_received >= HEADER_SIZE) {
112 uint32_t len = decode_header(task->receive_buf,
113 task->receive_buf_received);
114 if (len == 0 ||
115 len > (task->payload_len - HEADER_SIZE)) {
116 error_report("Message len %u must be non-zero & less than %zu",
117 len, (task->payload_len - HEADER_SIZE));
118 task->status_code = TDX_VP_GET_QUOTE_ERROR;
119 goto end;
120 }
121
122 /* Now we know the size, shrink to fit */
123 task->payload_len = HEADER_SIZE + len;
124 task->receive_buf = g_renew(char,
125 task->receive_buf,
126 task->payload_len);
127 }
128
129 if (task->receive_buf_received >= (sizeof(qgs_msg_header_t) + HEADER_SIZE)) {
130 qgs_msg_header_t *hdr = (qgs_msg_header_t *)(task->receive_buf + HEADER_SIZE);
131 if (hdr->major_version != QGS_MSG_LIB_MAJOR_VER ||
132 hdr->minor_version != QGS_MSG_LIB_MINOR_VER) {
133 error_report("Invalid QGS message header version %d.%d",
134 hdr->major_version,
135 hdr->minor_version);
136 task->status_code = TDX_VP_GET_QUOTE_ERROR;
137 goto end;
138 }
139 if (hdr->type != GET_QUOTE_RESP) {
140 error_report("Invalid QGS message type %d",
141 hdr->type);
142 task->status_code = TDX_VP_GET_QUOTE_ERROR;
143 goto end;
144 }
145 if (hdr->size > (task->payload_len - HEADER_SIZE)) {
146 error_report("QGS message size %d exceeds payload capacity %zu",
147 hdr->size, task->payload_len);
148 task->status_code = TDX_VP_GET_QUOTE_ERROR;
149 goto end;
150 }
151 if (hdr->error_code != 0) {
152 error_report("QGS message error code %d",
153 hdr->error_code);
154 task->status_code = TDX_VP_GET_QUOTE_ERROR;
155 goto end;
156 }
157 }
158 if (task->receive_buf_received >= (sizeof(qgs_msg_get_quote_resp_t) + HEADER_SIZE)) {
159 qgs_msg_get_quote_resp_t *msg = (qgs_msg_get_quote_resp_t *)(task->receive_buf + HEADER_SIZE);
160 if (msg->selected_id_size != 0) {
161 error_report("QGS message selected ID was %d not 0",
162 msg->selected_id_size);
163 task->status_code = TDX_VP_GET_QUOTE_ERROR;
164 goto end;
165 }
166
167 if ((task->payload_len - HEADER_SIZE - sizeof(qgs_msg_get_quote_resp_t)) !=
168 msg->quote_size) {
169 error_report("QGS quote size %d should be %zu",
170 msg->quote_size,
171 (task->payload_len - sizeof(qgs_msg_get_quote_resp_t)));
172 task->status_code = TDX_VP_GET_QUOTE_ERROR;
173 goto end;
174 }
175 }
176
177 if (task->receive_buf_received == task->payload_len) {
178 size_t strip = HEADER_SIZE + sizeof(qgs_msg_get_quote_resp_t);
179 memmove(task->receive_buf,
180 task->receive_buf + strip,
181 task->receive_buf_received - strip);
182 task->receive_buf_received -= strip;
183 task->status_code = TDX_VP_GET_QUOTE_SUCCESS;
184 goto end;
185 }
186
187 return G_SOURCE_CONTINUE;
188
189 end:
190 tdx_generate_quote_cleanup(task);
191 return G_SOURCE_REMOVE;
192 }
193
tdx_send_report(QIOChannel * ioc,GIOCondition condition,gpointer opaque)194 static gboolean tdx_send_report(QIOChannel *ioc, GIOCondition condition,
195 gpointer opaque)
196 {
197 TdxGenerateQuoteTask *task = opaque;
198 Error *err = NULL;
199 int ret;
200
201 ret = qio_channel_write(ioc, task->send_data + task->send_data_sent,
202 task->send_data_size - task->send_data_sent, &err);
203 if (ret < 0) {
204 if (ret == QIO_CHANNEL_ERR_BLOCK) {
205 ret = 0;
206 } else {
207 error_report_err(err);
208 task->status_code = TDX_VP_GET_QUOTE_ERROR;
209 tdx_generate_quote_cleanup(task);
210 goto end;
211 }
212 }
213 task->send_data_sent += ret;
214
215 if (task->send_data_sent == task->send_data_size) {
216 task->watch = qio_channel_add_watch(QIO_CHANNEL(task->sioc), G_IO_IN,
217 tdx_get_quote_read, task, NULL);
218 goto end;
219 }
220
221 return G_SOURCE_CONTINUE;
222
223 end:
224 return G_SOURCE_REMOVE;
225 }
226
tdx_quote_generator_connected(QIOTask * qio_task,gpointer opaque)227 static void tdx_quote_generator_connected(QIOTask *qio_task, gpointer opaque)
228 {
229 TdxGenerateQuoteTask *task = opaque;
230 Error *err = NULL;
231 int ret;
232
233 ret = qio_task_propagate_error(qio_task, &err);
234 if (ret) {
235 error_report_err(err);
236 task->status_code = TDX_VP_GET_QUOTE_QGS_UNAVAILABLE;
237 tdx_generate_quote_cleanup(task);
238 return;
239 }
240
241 task->watch = qio_channel_add_watch(QIO_CHANNEL(task->sioc), G_IO_OUT,
242 tdx_send_report, task, NULL);
243 }
244
245 #define TRANSACTION_TIMEOUT 30000
246
getquote_expired(void * opaque)247 static void getquote_expired(void *opaque)
248 {
249 TdxGenerateQuoteTask *task = opaque;
250
251 task->status_code = TDX_VP_GET_QUOTE_ERROR;
252 tdx_generate_quote_cleanup(task);
253 }
254
setup_get_quote_timer(TdxGenerateQuoteTask * task)255 static void setup_get_quote_timer(TdxGenerateQuoteTask *task)
256 {
257 int64_t time;
258
259 timer_init_ms(&task->timer, QEMU_CLOCK_VIRTUAL, getquote_expired, task);
260 time = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
261 timer_mod(&task->timer, time + TRANSACTION_TIMEOUT);
262 }
263
tdx_generate_quote(TdxGenerateQuoteTask * task,SocketAddress * qg_sock_addr)264 void tdx_generate_quote(TdxGenerateQuoteTask *task,
265 SocketAddress *qg_sock_addr)
266 {
267 QIOChannelSocket *sioc;
268 qgs_msg_get_quote_req_t msg;
269
270 /* Prepare a QGS message prelude */
271 msg.header.major_version = QGS_MSG_LIB_MAJOR_VER;
272 msg.header.minor_version = QGS_MSG_LIB_MINOR_VER;
273 msg.header.type = GET_QUOTE_REQ;
274 msg.header.size = sizeof(msg) + task->send_data_size;
275 msg.header.error_code = 0;
276 msg.report_size = task->send_data_size;
277 msg.id_list_size = 0;
278
279 /* Make room to add the QGS message prelude */
280 task->send_data = g_renew(char,
281 task->send_data,
282 task->send_data_size + sizeof(msg) + HEADER_SIZE);
283 memmove(task->send_data + sizeof(msg) + HEADER_SIZE,
284 task->send_data,
285 task->send_data_size);
286 memcpy(task->send_data + HEADER_SIZE,
287 &msg,
288 sizeof(msg));
289 encode_header(task->send_data, HEADER_SIZE, task->send_data_size + sizeof(msg));
290 task->send_data_size += sizeof(msg) + HEADER_SIZE;
291
292 sioc = qio_channel_socket_new();
293 task->sioc = sioc;
294
295 setup_get_quote_timer(task);
296
297 qio_channel_socket_connect_async(sioc, qg_sock_addr,
298 tdx_quote_generator_connected, task,
299 NULL, NULL);
300 }
301