diff options
Diffstat (limited to 'input/ipc-win.c')
| -rw-r--r-- | input/ipc-win.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/input/ipc-win.c b/input/ipc-win.c new file mode 100644 index 0000000..b0200ea --- /dev/null +++ b/input/ipc-win.c @@ -0,0 +1,509 @@ +/* + * This file is part of mpv. + * + * mpv is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * mpv is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with mpv. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <windows.h> +#include <sddl.h> + +#include "osdep/io.h" +#include "osdep/threads.h" +#include "osdep/windows_utils.h" + +#include "common/common.h" +#include "common/global.h" +#include "common/msg.h" +#include "input/input.h" +#include "libmpv/client.h" +#include "options/m_config.h" +#include "options/options.h" +#include "player/client.h" + +struct mp_ipc_ctx { + struct mp_log *log; + struct mp_client_api *client_api; + const wchar_t *path; + + mp_thread thread; + HANDLE death_event; +}; + +struct client_arg { + struct mp_log *log; + struct mpv_handle *client; + + char *client_name; + HANDLE client_h; + bool writable; + OVERLAPPED write_ol; +}; + +// Get a string SID representing the current user. Must be freed by LocalFree. +static char *get_user_sid(void) +{ + char *ssid = NULL; + TOKEN_USER *info = NULL; + HANDLE t; + if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &t)) + goto done; + + DWORD info_len; + if (!GetTokenInformation(t, TokenUser, NULL, 0, &info_len) && + GetLastError() != ERROR_INSUFFICIENT_BUFFER) + goto done; + + info = talloc_size(NULL, info_len); + if (!GetTokenInformation(t, TokenUser, info, info_len, &info_len)) + goto done; + if (!info->User.Sid) + goto done; + + ConvertSidToStringSidA(info->User.Sid, &ssid); +done: + if (t) + CloseHandle(t); + talloc_free(info); + return ssid; +} + +// Get a string SID for the process integrity level. Must be freed by LocalFree. +static char *get_integrity_sid(void) +{ + char *ssid = NULL; + TOKEN_MANDATORY_LABEL *info = NULL; + HANDLE t; + if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &t)) + goto done; + + DWORD info_len; + if (!GetTokenInformation(t, TokenIntegrityLevel, NULL, 0, &info_len) && + GetLastError() != ERROR_INSUFFICIENT_BUFFER) + goto done; + + info = talloc_size(NULL, info_len); + if (!GetTokenInformation(t, TokenIntegrityLevel, info, info_len, &info_len)) + goto done; + if (!info->Label.Sid) + goto done; + + ConvertSidToStringSidA(info->Label.Sid, &ssid); +done: + if (t) + CloseHandle(t); + talloc_free(info); + return ssid; +} + +// Create a security descriptor that only grants access to processes running +// under the current user at the current integrity level or higher +static PSECURITY_DESCRIPTOR create_restricted_sd(void) +{ + char *user_sid = get_user_sid(); + char *integrity_sid = get_integrity_sid(); + if (!user_sid || !integrity_sid) + return NULL; + + char *sddl = talloc_asprintf(NULL, + "O:%s" // Set the owner to user_sid + "D:(A;;GRGW;;;%s)" // Grant GENERIC_{READ,WRITE} access to user_sid + "S:(ML;;NRNWNX;;;%s)", // Disallow read, write and execute permissions + // to integrity levels below integrity_sid + user_sid, user_sid, integrity_sid); + LocalFree(user_sid); + LocalFree(integrity_sid); + + PSECURITY_DESCRIPTOR sd = NULL; + ConvertStringSecurityDescriptorToSecurityDescriptorA(sddl, SDDL_REVISION_1, + &sd, NULL); + talloc_free(sddl); + + return sd; +} + +static void wakeup_cb(void *d) +{ + HANDLE event = d; + SetEvent(event); +} + +// Wrapper for ReadFile that treats ERROR_IO_PENDING as success +static DWORD async_read(HANDLE file, void *buf, unsigned size, OVERLAPPED* ol) +{ + DWORD err = ReadFile(file, buf, size, NULL, ol) ? 0 : GetLastError(); + return err == ERROR_IO_PENDING ? 0 : err; +} + +// Wrapper for WriteFile that treats ERROR_IO_PENDING as success +static DWORD async_write(HANDLE file, const void *buf, unsigned size, OVERLAPPED* ol) +{ + DWORD err = WriteFile(file, buf, size, NULL, ol) ? 0 : GetLastError(); + return err == ERROR_IO_PENDING ? 0 : err; +} + +static bool pipe_error_is_fatal(DWORD error) +{ + switch (error) { + case 0: + case ERROR_HANDLE_EOF: + case ERROR_BROKEN_PIPE: + case ERROR_PIPE_NOT_CONNECTED: + case ERROR_NO_DATA: + return false; + } + return true; +} + +static DWORD ipc_write_str(struct client_arg *arg, const char *buf) +{ + DWORD error = 0; + + if ((error = async_write(arg->client_h, buf, strlen(buf), &arg->write_ol))) + goto done; + if (!GetOverlappedResult(arg->client_h, &arg->write_ol, &(DWORD){0}, TRUE)) { + error = GetLastError(); + goto done; + } + +done: + if (pipe_error_is_fatal(error)) { + MP_VERBOSE(arg, "Error writing to pipe: %s\n", + mp_HRESULT_to_str(HRESULT_FROM_WIN32(error))); + } + + if (error) + arg->writable = false; + return error; +} + +static void report_read_error(struct client_arg *arg, DWORD error) +{ + // Only report the error if it's not just due to the pipe closing + if (pipe_error_is_fatal(error)) { + MP_ERR(arg, "Error reading from pipe: %s\n", + mp_HRESULT_to_str(HRESULT_FROM_WIN32(error))); + } else { + MP_VERBOSE(arg, "Client disconnected\n"); + } +} + +static MP_THREAD_VOID client_thread(void *p) +{ + struct client_arg *arg = p; + char buf[4096]; + HANDLE wakeup_event = CreateEventW(NULL, TRUE, FALSE, NULL); + OVERLAPPED ol = { .hEvent = CreateEventW(NULL, TRUE, TRUE, NULL) }; + bstr client_msg = { talloc_strdup(NULL, ""), 0 }; + DWORD ioerr = 0; + DWORD r; + + char *tname = talloc_asprintf(NULL, "ipc/%s", arg->client_name); + mp_thread_set_name(tname); + talloc_free(tname); + + arg->write_ol.hEvent = CreateEventW(NULL, TRUE, TRUE, NULL); + if (!wakeup_event || !ol.hEvent || !arg->write_ol.hEvent) { + MP_ERR(arg, "Couldn't create events\n"); + goto done; + } + + MP_VERBOSE(arg, "Client connected\n"); + + mpv_set_wakeup_callback(arg->client, wakeup_cb, wakeup_event); + + // Do the first read operation on the pipe + if ((ioerr = async_read(arg->client_h, buf, 4096, &ol))) { + report_read_error(arg, ioerr); + goto done; + } + + while (1) { + HANDLE handles[] = { wakeup_event, ol.hEvent }; + int n = WaitForMultipleObjects(2, handles, FALSE, 0); + if (n == WAIT_TIMEOUT) + n = WaitForMultipleObjects(2, handles, FALSE, INFINITE); + + switch (n) { + case WAIT_OBJECT_0: // wakeup_event + ResetEvent(wakeup_event); + + while (1) { + mpv_event *event = mpv_wait_event(arg->client, 0); + + if (event->event_id == MPV_EVENT_NONE) + break; + + if (event->event_id == MPV_EVENT_SHUTDOWN) + goto done; + + if (!arg->writable) + continue; + + char *event_msg = mp_json_encode_event(event); + if (!event_msg) { + MP_ERR(arg, "Encoding error\n"); + goto done; + } + + ipc_write_str(arg, event_msg); + talloc_free(event_msg); + } + + break; + case WAIT_OBJECT_0 + 1: // ol.hEvent + // Complete the read operation on the pipe + if (!GetOverlappedResult(arg->client_h, &ol, &r, TRUE)) { + report_read_error(arg, GetLastError()); + goto done; + } + + bstr_xappend(NULL, &client_msg, (bstr){buf, r}); + while (bstrchr(client_msg, '\n') != -1) { + char *reply_msg = mp_ipc_consume_next_command(arg->client, + NULL, &client_msg); + if (reply_msg && arg->writable) + ipc_write_str(arg, reply_msg); + talloc_free(reply_msg); + } + + // Begin the next read operation on the pipe + if ((ioerr = async_read(arg->client_h, buf, 4096, &ol))) { + report_read_error(arg, ioerr); + goto done; + } + break; + default: + MP_ERR(arg, "WaitForMultipleObjects failed\n"); + goto done; + } + } + +done: + if (client_msg.len > 0) + MP_WARN(arg, "Ignoring unterminated command on disconnect.\n"); + + if (CancelIoEx(arg->client_h, &ol) || GetLastError() != ERROR_NOT_FOUND) + GetOverlappedResult(arg->client_h, &ol, &(DWORD){0}, TRUE); + if (wakeup_event) + CloseHandle(wakeup_event); + if (ol.hEvent) + CloseHandle(ol.hEvent); + if (arg->write_ol.hEvent) + CloseHandle(arg->write_ol.hEvent); + + CloseHandle(arg->client_h); + mpv_destroy(arg->client); + talloc_free(arg); + MP_THREAD_RETURN(); +} + +static void ipc_start_client(struct mp_ipc_ctx *ctx, struct client_arg *client) +{ + client->client = mp_new_client(ctx->client_api, client->client_name), + client->log = mp_client_get_log(client->client); + + mp_thread client_thr; + if (mp_thread_create(&client_thr, client_thread, client)) { + mpv_destroy(client->client); + CloseHandle(client->client_h); + talloc_free(client); + } + mp_thread_detach(client_thr); +} + +static void ipc_start_client_json(struct mp_ipc_ctx *ctx, int id, HANDLE h) +{ + struct client_arg *client = talloc_ptrtype(NULL, client); + *client = (struct client_arg){ + .client_name = talloc_asprintf(client, "ipc-%d", id), + .client_h = h, + .writable = true, + }; + + ipc_start_client(ctx, client); +} + +bool mp_ipc_start_anon_client(struct mp_ipc_ctx *ctx, struct mpv_handle *h, + int out_fd[2]) +{ + return false; +} + +static MP_THREAD_VOID ipc_thread(void *p) +{ + // Use PIPE_TYPE_MESSAGE | PIPE_READMODE_BYTE so message framing is + // maintained for message-mode clients, but byte-mode clients can still + // connect, send and receive data. This is the most compatible mode. + static const DWORD state = + PIPE_TYPE_MESSAGE | PIPE_READMODE_BYTE | PIPE_WAIT | + PIPE_REJECT_REMOTE_CLIENTS; + static const DWORD mode = + PIPE_ACCESS_DUPLEX | FILE_FLAG_OVERLAPPED; + static const DWORD bufsiz = 4096; + + struct mp_ipc_ctx *arg = p; + HANDLE server = INVALID_HANDLE_VALUE; + HANDLE client = INVALID_HANDLE_VALUE; + int client_num = 0; + + mp_thread_set_name("ipc/named-pipe"); + MP_VERBOSE(arg, "Starting IPC master\n"); + + OVERLAPPED ol = {0}; + SECURITY_ATTRIBUTES sa = { + .nLength = sizeof sa, + .lpSecurityDescriptor = create_restricted_sd(), + }; + if (!sa.lpSecurityDescriptor) { + MP_ERR(arg, "Couldn't create security descriptor"); + goto done; + } + + ol = (OVERLAPPED){ .hEvent = CreateEventW(NULL, TRUE, TRUE, NULL) }; + if (!ol.hEvent) { + MP_ERR(arg, "Couldn't create event"); + goto done; + } + + server = CreateNamedPipeW(arg->path, mode | FILE_FLAG_FIRST_PIPE_INSTANCE, + state, PIPE_UNLIMITED_INSTANCES, bufsiz, bufsiz, 0, &sa); + if (server == INVALID_HANDLE_VALUE) { + MP_ERR(arg, "Couldn't create first pipe instance: %s\n", + mp_LastError_to_str()); + goto done; + } + + MP_VERBOSE(arg, "Listening to IPC pipe.\n"); + + while (1) { + DWORD err = ConnectNamedPipe(server, &ol) ? 0 : GetLastError(); + + if (err == ERROR_IO_PENDING) { + int n = WaitForMultipleObjects(2, (HANDLE[]) { + arg->death_event, + ol.hEvent, + }, FALSE, INFINITE) - WAIT_OBJECT_0; + + switch (n) { + case 0: + // Stop waiting for new clients + CancelIo(server); + GetOverlappedResult(server, &ol, &(DWORD){0}, TRUE); + goto done; + case 1: + // Complete the ConnectNamedPipe request + err = GetOverlappedResult(server, &ol, &(DWORD){0}, TRUE) + ? 0 : GetLastError(); + break; + default: + MP_ERR(arg, "WaitForMultipleObjects failed\n"); + goto done; + } + } + + // ERROR_PIPE_CONNECTED is returned if a client connects before + // ConnectNamedPipe is called. ERROR_NO_DATA is returned if a client + // connects, (possibly) writes data and exits before ConnectNamedPipe + // is called. Both cases should be handled as normal connections. + if (err == ERROR_PIPE_CONNECTED || err == ERROR_NO_DATA) + err = 0; + + if (err) { + MP_ERR(arg, "ConnectNamedPipe failed: %s\n", + mp_HRESULT_to_str(HRESULT_FROM_WIN32(err))); + goto done; + } + + // Create the next pipe instance before the client thread to avoid the + // theoretical race condition where the client thread immediately + // closes the handle and there are no active instances of the pipe + client = server; + server = CreateNamedPipeW(arg->path, mode, state, + PIPE_UNLIMITED_INSTANCES, bufsiz, bufsiz, 0, &sa); + if (server == INVALID_HANDLE_VALUE) { + MP_ERR(arg, "Couldn't create additional pipe instance: %s\n", + mp_LastError_to_str()); + goto done; + } + + ipc_start_client_json(arg, client_num++, client); + client = NULL; + } + +done: + if (sa.lpSecurityDescriptor) + LocalFree(sa.lpSecurityDescriptor); + if (client != INVALID_HANDLE_VALUE) + CloseHandle(client); + if (server != INVALID_HANDLE_VALUE) + CloseHandle(server); + if (ol.hEvent) + CloseHandle(ol.hEvent); + MP_THREAD_RETURN(); +} + +struct mp_ipc_ctx *mp_init_ipc(struct mp_client_api *client_api, + struct mpv_global *global) +{ + struct MPOpts *opts = mp_get_config_group(NULL, global, &mp_opt_root); + + struct mp_ipc_ctx *arg = talloc_ptrtype(NULL, arg); + *arg = (struct mp_ipc_ctx){ + .log = mp_log_new(arg, global->log, "ipc"), + .client_api = client_api, + }; + + if (!opts->ipc_path || !*opts->ipc_path) + goto out; + + // Ensure the path is a legal Win32 pipe name by prepending \\.\pipe\ if + // it's not already present. Qt's QLocalSocket uses the same logic, so + // cross-platform programs that use paths like /tmp/mpv-socket should just + // work. (Win32 converts this path to \Device\NamedPipe\tmp\mpv-socket) + if (!strncmp(opts->ipc_path, "\\\\.\\pipe\\", 9)) { + arg->path = mp_from_utf8(arg, opts->ipc_path); + } else { + char *path = talloc_asprintf(NULL, "\\\\.\\pipe\\%s", opts->ipc_path); + arg->path = mp_from_utf8(arg, path); + talloc_free(path); + } + + if (!(arg->death_event = CreateEventW(NULL, TRUE, FALSE, NULL))) + goto out; + + if (mp_thread_create(&arg->thread, ipc_thread, arg)) + goto out; + + talloc_free(opts); + return arg; + +out: + if (arg->death_event) + CloseHandle(arg->death_event); + talloc_free(arg); + talloc_free(opts); + return NULL; +} + +void mp_uninit_ipc(struct mp_ipc_ctx *arg) +{ + if (!arg) + return; + + SetEvent(arg->death_event); + mp_thread_join(arg->thread); + + CloseHandle(arg->death_event); + talloc_free(arg); +} |