The vdagent protocol allows the guest agent (spice-vdagent) and the
spice client exchange messages to implement features which require
guest cooperation, for example clipboard support.
This is a qemu implementation of the spice client side. This allows
the spice guest agent talk to qemu directly when not using the spice
protocol.
usage: qemu \
-chardev qemu-vdagent,id=vdagent \
-device virtserialport,chardev=vdagent,name=com.redhat.spice.0
This patch adds just the protocol basics: initial handshake and
capability negotiation. The following patches will add actual
functionality and also add fields to the initially empty
ChardevVDAgent qapi struct.
Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
Acked-by: Markus Armbruster <arm...@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
Message-id: 20210519053940.1888907-1-kra...@redhat.com
Message-Id: <20210519053940.1888907-5-kra...@redhat.com>
---
ui/vdagent.c | 361 ++++++++++++++++++++++++++++++++++++++++++++++++
qapi/char.json | 17 ++-
ui/meson.build | 1 +
ui/trace-events | 8 ++
4 files changed, 386 insertions(+), 1 deletion(-)
create mode 100644 ui/vdagent.c
diff --git a/ui/vdagent.c b/ui/vdagent.c
new file mode 100644
index 000000000000..21e55a41eaba
--- /dev/null
+++ b/ui/vdagent.c
@@ -0,0 +1,361 @@
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "include/qemu-common.h"
+#include "chardev/char.h"
+#include "qemu/buffer.h"
+#include "qemu/units.h"
+#include "trace.h"
+
+#include "qapi/qapi-types-char.h"
+
+#include "spice/vd_agent.h"
+
+#define VDAGENT_BUFFER_LIMIT (1 * MiB)
+
+struct VDAgentChardev {
+ Chardev parent;
+
+ /* guest vdagent */
+ uint32_t caps;
+ VDIChunkHeader chunk;
+ uint32_t chunksize;
+ uint8_t *msgbuf;
+ uint32_t msgsize;
+ uint8_t *xbuf;
+ uint32_t xoff, xsize;
+ Buffer outbuf;
+};
+typedef struct VDAgentChardev VDAgentChardev;
+
+#define TYPE_CHARDEV_QEMU_VDAGENT "chardev-qemu-vdagent"
+
+DECLARE_INSTANCE_CHECKER(VDAgentChardev, QEMU_VDAGENT_CHARDEV,
+ TYPE_CHARDEV_QEMU_VDAGENT);
+
+/* ------------------------------------------------------------------ */
+/* names, for debug logging */
+
+static const char *cap_name[] = {
+ [VD_AGENT_CAP_MOUSE_STATE] = "mouse-state",
+ [VD_AGENT_CAP_MONITORS_CONFIG] = "monitors-config",
+ [VD_AGENT_CAP_REPLY] = "reply",
+ [VD_AGENT_CAP_CLIPBOARD] = "clipboard",
+ [VD_AGENT_CAP_DISPLAY_CONFIG] = "display-config",
+ [VD_AGENT_CAP_CLIPBOARD_BY_DEMAND] = "clipboard-by-demand",
+ [VD_AGENT_CAP_CLIPBOARD_SELECTION] = "clipboard-selection",
+ [VD_AGENT_CAP_SPARSE_MONITORS_CONFIG] = "sparse-monitors-config",
+ [VD_AGENT_CAP_GUEST_LINEEND_LF] = "guest-lineend-lf",
+ [VD_AGENT_CAP_GUEST_LINEEND_CRLF] = "guest-lineend-crlf",
+ [VD_AGENT_CAP_MAX_CLIPBOARD] = "max-clipboard",
+ [VD_AGENT_CAP_AUDIO_VOLUME_SYNC] = "audio-volume-sync",
+ [VD_AGENT_CAP_MONITORS_CONFIG_POSITION] = "monitors-config-position",
+ [VD_AGENT_CAP_FILE_XFER_DISABLED] = "file-xfer-disabled",
+ [VD_AGENT_CAP_FILE_XFER_DETAILED_ERRORS] =
"file-xfer-detailed-errors",
+#if 0
+ [VD_AGENT_CAP_GRAPHICS_DEVICE_INFO] = "graphics-device-info",
+ [VD_AGENT_CAP_CLIPBOARD_NO_RELEASE_ON_REGRAB] =
"clipboard-no-release-on-regrab",
+ [VD_AGENT_CAP_CLIPBOARD_GRAB_SERIAL] = "clipboard-grab-serial",
+#endif
+};
+
+static const char *msg_name[] = {
+ [VD_AGENT_MOUSE_STATE] = "mouse-state",
+ [VD_AGENT_MONITORS_CONFIG] = "monitors-config",
+ [VD_AGENT_REPLY] = "reply",
+ [VD_AGENT_CLIPBOARD] = "clipboard",
+ [VD_AGENT_DISPLAY_CONFIG] = "display-config",
+ [VD_AGENT_ANNOUNCE_CAPABILITIES] = "announce-capabilities",
+ [VD_AGENT_CLIPBOARD_GRAB] = "clipboard-grab",
+ [VD_AGENT_CLIPBOARD_REQUEST] = "clipboard-request",
+ [VD_AGENT_CLIPBOARD_RELEASE] = "clipboard-release",
+ [VD_AGENT_FILE_XFER_START] = "file-xfer-start",
+ [VD_AGENT_FILE_XFER_STATUS] = "file-xfer-status",
+ [VD_AGENT_FILE_XFER_DATA] = "file-xfer-data",
+ [VD_AGENT_CLIENT_DISCONNECTED] = "client-disconnected",
+ [VD_AGENT_MAX_CLIPBOARD] = "max-clipboard",
+ [VD_AGENT_AUDIO_VOLUME_SYNC] = "audio-volume-sync",
+#if 0
+ [VD_AGENT_GRAPHICS_DEVICE_INFO] = "graphics-device-info",
+#endif
+};
+
+#define GET_NAME(_m, _v) \
+ (((_v) < ARRAY_SIZE(_m) && (_m[_v])) ? (_m[_v]) : "???")
+
+/* ------------------------------------------------------------------ */
+/* send messages */
+
+static void vdagent_send_buf(VDAgentChardev *vd)
+{
+ uint32_t len;
+
+ while (!buffer_empty(&vd->outbuf)) {
+ len = qemu_chr_be_can_write(CHARDEV(vd));
+ if (len == 0) {
+ return;
+ }
+ if (len > vd->outbuf.offset) {
+ len = vd->outbuf.offset;
+ }
+ qemu_chr_be_write(CHARDEV(vd), vd->outbuf.buffer, len);
+ buffer_advance(&vd->outbuf, len);
+ }
+}
+
+static void vdagent_send_msg(VDAgentChardev *vd, VDAgentMessage *msg)
+{
+ uint8_t *msgbuf = (void *)msg;
+ uint32_t msgsize = sizeof(VDAgentMessage) + msg->size;
+ uint32_t msgoff = 0;
+ VDIChunkHeader chunk;
+
+ trace_vdagent_send(GET_NAME(msg_name, msg->type));
+
+ msg->protocol = VD_AGENT_PROTOCOL;
+
+ if (vd->outbuf.offset + msgsize > VDAGENT_BUFFER_LIMIT) {
+ error_report("buffer full, dropping message");
+ return;
+ }
+
+ while (msgoff < msgsize) {
+ chunk.port = VDP_CLIENT_PORT;
+ chunk.size = msgsize - msgoff;
+ if (chunk.size > 1024) {
+ chunk.size = 1024;
+ }
+ buffer_reserve(&vd->outbuf, sizeof(chunk) + chunk.size);
+ buffer_append(&vd->outbuf, &chunk, sizeof(chunk));
+ buffer_append(&vd->outbuf, msgbuf + msgoff, chunk.size);
+ msgoff += chunk.size;
+ }
+ vdagent_send_buf(vd);
+}
+
+static void vdagent_send_caps(VDAgentChardev *vd)
+{
+ g_autofree VDAgentMessage *msg = g_malloc0(sizeof(VDAgentMessage) +
+
sizeof(VDAgentAnnounceCapabilities) +
+ sizeof(uint32_t));
+
+ msg->type = VD_AGENT_ANNOUNCE_CAPABILITIES;
+ msg->size = sizeof(VDAgentAnnounceCapabilities) + sizeof(uint32_t);
+
+ vdagent_send_msg(vd, msg);
+}
+
+/* ------------------------------------------------------------------ */
+/* chardev backend */
+
+static void vdagent_chr_open(Chardev *chr,
+ ChardevBackend *backend,
+ bool *be_opened,
+ Error **errp)
+{
+#if defined(HOST_WORDS_BIGENDIAN)
+ /*
+ * TODO: vdagent protocol is defined to be LE,
+ * so we have to byteswap everything on BE hosts.
+ */
+ error_setg(errp, "vdagent is not supported on bigendian hosts");
+ return;
+#endif
+
+ *be_opened = true;
+}
+
+static void vdagent_chr_recv_caps(VDAgentChardev *vd, VDAgentMessage *msg)
+{
+ VDAgentAnnounceCapabilities *caps = (void *)msg->data;
+ int i;
+
+ if (msg->size < (sizeof(VDAgentAnnounceCapabilities) +
+ sizeof(uint32_t))) {
+ return;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(cap_name); i++) {
+ if (caps->caps[0] & (1 << i)) {
+ trace_vdagent_peer_cap(GET_NAME(cap_name, i));
+ }
+ }
+
+ vd->caps = caps->caps[0];
+ if (caps->request) {
+ vdagent_send_caps(vd);
+ }
+}
+
+static void vdagent_chr_recv_msg(VDAgentChardev *vd, VDAgentMessage *msg)
+{
+ trace_vdagent_recv_msg(GET_NAME(msg_name, msg->type), msg->size);
+
+ switch (msg->type) {
+ case VD_AGENT_ANNOUNCE_CAPABILITIES:
+ vdagent_chr_recv_caps(vd, msg);
+ break;
+ default:
+ break;
+ }
+}
+
+static void vdagent_reset_xbuf(VDAgentChardev *vd)
+{
+ g_clear_pointer(&vd->xbuf, g_free);
+ vd->xoff = 0;
+ vd->xsize = 0;
+}
+
+static void vdagent_chr_recv_chunk(VDAgentChardev *vd)
+{
+ VDAgentMessage *msg = (void *)vd->msgbuf;
+
+ if (!vd->xsize) {
+ if (vd->msgsize < sizeof(*msg)) {
+ error_report("%s: message too small: %d < %zd", __func__,
+ vd->msgsize, sizeof(*msg));
+ return;
+ }
+ if (vd->msgsize == msg->size + sizeof(*msg)) {
+ vdagent_chr_recv_msg(vd, msg);
+ return;
+ }
+ }
+
+ if (!vd->xsize) {
+ vd->xsize = msg->size + sizeof(*msg);
+ vd->xbuf = g_malloc0(vd->xsize);
+ }
+
+ if (vd->xoff + vd->msgsize > vd->xsize) {
+ error_report("%s: Oops: %d+%d > %d", __func__,
+ vd->xoff, vd->msgsize, vd->xsize);
+ vdagent_reset_xbuf(vd);
+ return;
+ }
+
+ memcpy(vd->xbuf + vd->xoff, vd->msgbuf, vd->msgsize);
+ vd->xoff += vd->msgsize;
+ if (vd->xoff < vd->xsize) {
+ return;
+ }
+
+ msg = (void *)vd->xbuf;
+ vdagent_chr_recv_msg(vd, msg);
+ vdagent_reset_xbuf(vd);
+}
+
+static void vdagent_reset_bufs(VDAgentChardev *vd)
+{
+ memset(&vd->chunk, 0, sizeof(vd->chunk));
+ vd->chunksize = 0;
+ g_free(vd->msgbuf);
+ vd->msgbuf = NULL;
+ vd->msgsize = 0;
+}
+
+static int vdagent_chr_write(Chardev *chr, const uint8_t *buf, int len)
+{
+ VDAgentChardev *vd = QEMU_VDAGENT_CHARDEV(chr);
+ uint32_t copy, ret = len;
+
+ while (len) {
+ if (vd->chunksize < sizeof(vd->chunk)) {
+ copy = sizeof(vd->chunk) - vd->chunksize;
+ if (copy > len) {
+ copy = len;
+ }
+ memcpy((void *)(&vd->chunk) + vd->chunksize, buf, copy);
+ vd->chunksize += copy;
+ buf += copy;
+ len -= copy;
+ if (vd->chunksize < sizeof(vd->chunk)) {
+ break;
+ }
+
+ assert(vd->msgbuf == NULL);
+ vd->msgbuf = g_malloc0(vd->chunk.size);
+ }
+
+ copy = vd->chunk.size - vd->msgsize;
+ if (copy > len) {
+ copy = len;
+ }
+ memcpy(vd->msgbuf + vd->msgsize, buf, copy);
+ vd->msgsize += copy;
+ buf += copy;
+ len -= copy;
+
+ if (vd->msgsize == vd->chunk.size) {
+ trace_vdagent_recv_chunk(vd->chunk.size);
+ vdagent_chr_recv_chunk(vd);
+ vdagent_reset_bufs(vd);
+ }
+ }
+
+ return ret;
+}
+
+static void vdagent_chr_accept_input(Chardev *chr)
+{
+ VDAgentChardev *vd = QEMU_VDAGENT_CHARDEV(chr);
+
+ vdagent_send_buf(vd);
+}
+
+static void vdagent_chr_set_fe_open(struct Chardev *chr, int fe_open)
+{
+ VDAgentChardev *vd = QEMU_VDAGENT_CHARDEV(chr);
+
+ if (!fe_open) {
+ trace_vdagent_close();
+ /* reset state */
+ vdagent_reset_bufs(vd);
+ vd->caps = 0;
+ return;
+ }
+
+ trace_vdagent_open();
+}
+
+/* ------------------------------------------------------------------ */
+
+static void vdagent_chr_class_init(ObjectClass *oc, void *data)
+{
+ ChardevClass *cc = CHARDEV_CLASS(oc);
+
+ cc->open = vdagent_chr_open;
+ cc->chr_write = vdagent_chr_write;
+ cc->chr_set_fe_open = vdagent_chr_set_fe_open;
+ cc->chr_accept_input = vdagent_chr_accept_input;
+}
+
+static void vdagent_chr_init(Object *obj)
+{
+ VDAgentChardev *vd = QEMU_VDAGENT_CHARDEV(obj);
+
+ buffer_init(&vd->outbuf, "vdagent-outbuf");
+}
+
+static void vdagent_chr_fini(Object *obj)
+{
+ VDAgentChardev *vd = QEMU_VDAGENT_CHARDEV(obj);
+
+ buffer_free(&vd->outbuf);
+}
+
+static const TypeInfo vdagent_chr_type_info = {
+ .name = TYPE_CHARDEV_QEMU_VDAGENT,
+ .parent = TYPE_CHARDEV,
+ .instance_size = sizeof(VDAgentChardev),
+ .instance_init = vdagent_chr_init,
+ .instance_finalize = vdagent_chr_fini,
+ .class_init = vdagent_chr_class_init,
+};
+
+static void register_types(void)
+{
+ type_register_static(&vdagent_chr_type_info);
+}
+
+type_init(register_types);
diff --git a/qapi/char.json b/qapi/char.json
index 6413970fa73b..990801e642bb 100644
--- a/qapi/char.json
+++ b/qapi/char.json
@@ -390,12 +390,25 @@
'data': { '*size': 'int' },
'base': 'ChardevCommon' }
+##
+# @ChardevQemuVDAgent:
+#
+# Configuration info for qemu vdagent implementation.
+#
+# Since: 6.1
+#
+##
+{ 'struct': 'ChardevQemuVDAgent',
+ 'data': { },
+ 'base': 'ChardevCommon',
+ 'if': 'defined(CONFIG_SPICE_PROTOCOL)' }
+
##
# @ChardevBackend:
#
# Configuration info for the new chardev backend.
#
-# Since: 1.4 (testdev since 2.2, wctablet since 2.9)
+# Since: 1.4 (testdev since 2.2, wctablet since 2.9, vdagent since 6.1)
##
{ 'union': 'ChardevBackend',
'data': { 'file': 'ChardevFile',
@@ -417,6 +430,8 @@
'if': 'defined(CONFIG_SPICE)' },
'spiceport': { 'type': 'ChardevSpicePort',
'if': 'defined(CONFIG_SPICE)' },
+ 'qemu-vdagent': { 'type': 'ChardevQemuVDAgent',
+ 'if': 'defined(CONFIG_SPICE_PROTOCOL)' },
'vc': 'ChardevVC',
'ringbuf': 'ChardevRingbuf',
# next one is just for compatibility
diff --git a/ui/meson.build b/ui/meson.build
index fc4fb75c2869..bad49fb6de60 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -14,6 +14,7 @@ softmmu_ss.add(files(
'qemu-pixman.c',
))
softmmu_ss.add([spice_headers, files('spice-module.c')])
+softmmu_ss.add(when: spice_protocol, if_true: files('vdagent.c'))
softmmu_ss.add(when: 'CONFIG_LINUX', if_true: files('input-linux.c'))
softmmu_ss.add(when: cocoa, if_true: files('cocoa.m'))
diff --git a/ui/trace-events b/ui/trace-events
index 5d1da6f23668..c34cffb0452b 100644
--- a/ui/trace-events
+++ b/ui/trace-events
@@ -124,3 +124,11 @@ xkeymap_extension(const char *name) "extension '%s'"
xkeymap_vendor(const char *name) "vendor '%s'"
xkeymap_keycodes(const char *name) "keycodes '%s'"
xkeymap_keymap(const char *name) "keymap '%s'"
+
+# vdagent.c
+vdagent_open(void) ""
+vdagent_close(void) ""
+vdagent_send(const char *name) "msg %s"
+vdagent_recv_chunk(uint32_t size) "size %d"
+vdagent_recv_msg(const char *name, uint32_t size) "msg %s, size %d"
+vdagent_peer_cap(const char *name) "cap %s"
--
2.31.1
