diff options
Diffstat (limited to 'target/i386/kvm/tdx-quote-generator.c')
| -rw-r--r-- | target/i386/kvm/tdx-quote-generator.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/target/i386/kvm/tdx-quote-generator.c b/target/i386/kvm/tdx-quote-generator.c new file mode 100644 index 0000000..f59715f --- /dev/null +++ b/target/i386/kvm/tdx-quote-generator.c @@ -0,0 +1,300 @@ +/* + * QEMU TDX Quote Generation Support + * + * Copyright (c) 2025 Intel Corporation + * + * Author: + * Xiaoyao Li <xiaoyao.li@intel.com> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "qemu/error-report.h" +#include "qapi/error.h" +#include "qapi/qapi-visit-sockets.h" + +#include "tdx-quote-generator.h" + +#define QGS_MSG_LIB_MAJOR_VER 1 +#define QGS_MSG_LIB_MINOR_VER 1 + +typedef enum _qgs_msg_type_t { + GET_QUOTE_REQ = 0, + GET_QUOTE_RESP = 1, + GET_COLLATERAL_REQ = 2, + GET_COLLATERAL_RESP = 3, + GET_PLATFORM_INFO_REQ = 4, + GET_PLATFORM_INFO_RESP = 5, + QGS_MSG_TYPE_MAX +} qgs_msg_type_t; + +typedef struct _qgs_msg_header_t { + uint16_t major_version; + uint16_t minor_version; + uint32_t type; + uint32_t size; // size of the whole message, include this header, in byte + uint32_t error_code; // used in response only +} qgs_msg_header_t; + +typedef struct _qgs_msg_get_quote_req_t { + qgs_msg_header_t header; // header.type = GET_QUOTE_REQ + uint32_t report_size; // cannot be 0 + uint32_t id_list_size; // length of id_list, in byte, can be 0 +} qgs_msg_get_quote_req_t; + +typedef struct _qgs_msg_get_quote_resp_s { + qgs_msg_header_t header; // header.type = GET_QUOTE_RESP + uint32_t selected_id_size; // can be 0 in case only one id is sent in request + uint32_t quote_size; // length of quote_data, in byte + uint8_t id_quote[]; // selected id followed by quote +} qgs_msg_get_quote_resp_t; + +#define HEADER_SIZE 4 + +static uint32_t decode_header(const char *buf, size_t len) { + if (len < HEADER_SIZE) { + return 0; + } + uint32_t msg_size = 0; + for (uint32_t i = 0; i < HEADER_SIZE; ++i) { + msg_size = msg_size * 256 + (buf[i] & 0xFF); + } + return msg_size; +} + +static void encode_header(char *buf, size_t len, uint32_t size) { + assert(len >= HEADER_SIZE); + buf[0] = ((size >> 24) & 0xFF); + buf[1] = ((size >> 16) & 0xFF); + buf[2] = ((size >> 8) & 0xFF); + buf[3] = (size & 0xFF); +} + +static void tdx_generate_quote_cleanup(TdxGenerateQuoteTask *task) +{ + timer_del(&task->timer); + + g_source_remove(task->watch); + qio_channel_close(QIO_CHANNEL(task->sioc), NULL); + object_unref(OBJECT(task->sioc)); + + task->completion(task); +} + +static gboolean tdx_get_quote_read(QIOChannel *ioc, GIOCondition condition, + gpointer opaque) +{ + TdxGenerateQuoteTask *task = opaque; + Error *err = NULL; + int ret; + + ret = qio_channel_read(ioc, task->receive_buf + task->receive_buf_received, + task->payload_len - task->receive_buf_received, &err); + if (ret < 0) { + if (ret == QIO_CHANNEL_ERR_BLOCK) { + return G_SOURCE_CONTINUE; + } else { + error_report_err(err); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + } + + if (ret == 0) { + error_report("End of file before reply received"); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + + task->receive_buf_received += ret; + if (task->receive_buf_received >= HEADER_SIZE) { + uint32_t len = decode_header(task->receive_buf, + task->receive_buf_received); + if (len == 0 || + len > (task->payload_len - HEADER_SIZE)) { + error_report("Message len %u must be non-zero & less than %zu", + len, (task->payload_len - HEADER_SIZE)); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + + /* Now we know the size, shrink to fit */ + task->payload_len = HEADER_SIZE + len; + task->receive_buf = g_renew(char, + task->receive_buf, + task->payload_len); + } + + if (task->receive_buf_received >= (sizeof(qgs_msg_header_t) + HEADER_SIZE)) { + qgs_msg_header_t *hdr = (qgs_msg_header_t *)(task->receive_buf + HEADER_SIZE); + if (hdr->major_version != QGS_MSG_LIB_MAJOR_VER || + hdr->minor_version != QGS_MSG_LIB_MINOR_VER) { + error_report("Invalid QGS message header version %d.%d", + hdr->major_version, + hdr->minor_version); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + if (hdr->type != GET_QUOTE_RESP) { + error_report("Invalid QGS message type %d", + hdr->type); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + if (hdr->size > (task->payload_len - HEADER_SIZE)) { + error_report("QGS message size %d exceeds payload capacity %zu", + hdr->size, task->payload_len); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + if (hdr->error_code != 0) { + error_report("QGS message error code %d", + hdr->error_code); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + } + if (task->receive_buf_received >= (sizeof(qgs_msg_get_quote_resp_t) + HEADER_SIZE)) { + qgs_msg_get_quote_resp_t *msg = (qgs_msg_get_quote_resp_t *)(task->receive_buf + HEADER_SIZE); + if (msg->selected_id_size != 0) { + error_report("QGS message selected ID was %d not 0", + msg->selected_id_size); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + + if ((task->payload_len - HEADER_SIZE - sizeof(qgs_msg_get_quote_resp_t)) != + msg->quote_size) { + error_report("QGS quote size %d should be %zu", + msg->quote_size, + (task->payload_len - sizeof(qgs_msg_get_quote_resp_t))); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + goto end; + } + } + + if (task->receive_buf_received == task->payload_len) { + size_t strip = HEADER_SIZE + sizeof(qgs_msg_get_quote_resp_t); + memmove(task->receive_buf, + task->receive_buf + strip, + task->receive_buf_received - strip); + task->receive_buf_received -= strip; + task->status_code = TDX_VP_GET_QUOTE_SUCCESS; + goto end; + } + + return G_SOURCE_CONTINUE; + +end: + tdx_generate_quote_cleanup(task); + return G_SOURCE_REMOVE; +} + +static gboolean tdx_send_report(QIOChannel *ioc, GIOCondition condition, + gpointer opaque) +{ + TdxGenerateQuoteTask *task = opaque; + Error *err = NULL; + int ret; + + ret = qio_channel_write(ioc, task->send_data + task->send_data_sent, + task->send_data_size - task->send_data_sent, &err); + if (ret < 0) { + if (ret == QIO_CHANNEL_ERR_BLOCK) { + ret = 0; + } else { + error_report_err(err); + task->status_code = TDX_VP_GET_QUOTE_ERROR; + tdx_generate_quote_cleanup(task); + goto end; + } + } + task->send_data_sent += ret; + + if (task->send_data_sent == task->send_data_size) { + task->watch = qio_channel_add_watch(QIO_CHANNEL(task->sioc), G_IO_IN, + tdx_get_quote_read, task, NULL); + goto end; + } + + return G_SOURCE_CONTINUE; + +end: + return G_SOURCE_REMOVE; +} + +static void tdx_quote_generator_connected(QIOTask *qio_task, gpointer opaque) +{ + TdxGenerateQuoteTask *task = opaque; + Error *err = NULL; + int ret; + + ret = qio_task_propagate_error(qio_task, &err); + if (ret) { + error_report_err(err); + task->status_code = TDX_VP_GET_QUOTE_QGS_UNAVAILABLE; + tdx_generate_quote_cleanup(task); + return; + } + + task->watch = qio_channel_add_watch(QIO_CHANNEL(task->sioc), G_IO_OUT, + tdx_send_report, task, NULL); +} + +#define TRANSACTION_TIMEOUT 30000 + +static void getquote_expired(void *opaque) +{ + TdxGenerateQuoteTask *task = opaque; + + task->status_code = TDX_VP_GET_QUOTE_ERROR; + tdx_generate_quote_cleanup(task); +} + +static void setup_get_quote_timer(TdxGenerateQuoteTask *task) +{ + int64_t time; + + timer_init_ms(&task->timer, QEMU_CLOCK_VIRTUAL, getquote_expired, task); + time = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL); + timer_mod(&task->timer, time + TRANSACTION_TIMEOUT); +} + +void tdx_generate_quote(TdxGenerateQuoteTask *task, + SocketAddress *qg_sock_addr) +{ + QIOChannelSocket *sioc; + qgs_msg_get_quote_req_t msg; + + /* Prepare a QGS message prelude */ + msg.header.major_version = QGS_MSG_LIB_MAJOR_VER; + msg.header.minor_version = QGS_MSG_LIB_MINOR_VER; + msg.header.type = GET_QUOTE_REQ; + msg.header.size = sizeof(msg) + task->send_data_size; + msg.header.error_code = 0; + msg.report_size = task->send_data_size; + msg.id_list_size = 0; + + /* Make room to add the QGS message prelude */ + task->send_data = g_renew(char, + task->send_data, + task->send_data_size + sizeof(msg) + HEADER_SIZE); + memmove(task->send_data + sizeof(msg) + HEADER_SIZE, + task->send_data, + task->send_data_size); + memcpy(task->send_data + HEADER_SIZE, + &msg, + sizeof(msg)); + encode_header(task->send_data, HEADER_SIZE, task->send_data_size + sizeof(msg)); + task->send_data_size += sizeof(msg) + HEADER_SIZE; + + sioc = qio_channel_socket_new(); + task->sioc = sioc; + + setup_get_quote_timer(task); + + qio_channel_socket_connect_async(sioc, qg_sock_addr, + tdx_quote_generator_connected, task, + NULL, NULL); +} |