diff --git a/CMake/FindLibcap.cmake b/CMake/FindLibcap.cmake new file mode 100644 index 00000000..b34e5e37 --- /dev/null +++ b/CMake/FindLibcap.cmake @@ -0,0 +1,56 @@ +#.rst: +# FindLibcap +# ------- +# +# Find Libcap library +# +# Try to find Libcap library. The following values are defined +# +# :: +# +# Libcap_FOUND - True if Libcap is available +# Libcap_INCLUDE_DIRS - Include directories for Libcap +# Libcap_LIBRARIES - List of libraries for Libcap +# Libcap_DEFINITIONS - List of definitions for Libcap +# +# and also the following more fine grained variables +# +# :: +# +# Libcap_VERSION +# Libcap_VERSION_MAJOR +# Libcap_VERSION_MINOR +# +#============================================================================= +# Copyright (c) 2017 Jerzi Kaminsky +# +# Distributed under the OSI-approved BSD License (the "License"); +# +# This software is distributed WITHOUT ANY WARRANTY; without even the +# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +# See the License for more information. +#============================================================================= + +include(FeatureSummary) +set_package_properties(Libcap PROPERTIES + URL "https://www.kernel.org/pub/linux/libs/security/linux-privs/libcap2" + DESCRIPTION "Library for getting and setting POSIX.1e capabilities") + +find_package(PkgConfig) +pkg_check_modules(PC_CAP QUIET Libcap) +find_library(Libcap_LIBRARIES NAMES cap HINTS ${PC_CAP_LIBRARY_DIRS}) +find_path(Libcap_INCLUDE_DIRS sys/capability.h HINTS ${PC_CAP_INCLUDE_DIRS}) + +set(Libcap_VERSION ${PC_CAP_VERSION}) +string(REPLACE "." ";" VERSION_LIST "${PC_CAP_VERSION}") + +LIST(LENGTH VERSION_LIST n) +if (n EQUAL 2) + list(GET VERSION_LIST 0 Libcap_VERSION_MAJOR) + list(GET VERSION_LIST 1 Libcap_VERSION_MINOR) +endif () + +include(FindPackageHandleStandardArgs) +find_package_handle_standard_args(Libcap DEFAULT_MSG Libcap_INCLUDE_DIRS Libcap_LIBRARIES) +mark_as_advanced(Libcap_INCLUDE_DIRS Libcap_LIBRARIES Libcap_DEFINITIONS + Libcap_VERSION Libcap_VERSION_MAJOR Libcap_VERSION_MICRO Libcap_VERSION_MINOR) diff --git a/CMakeLists.txt b/CMakeLists.txt index b15882ce..ba1cfba8 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -50,6 +50,7 @@ find_package(GBM REQUIRED) find_package(LibInput REQUIRED) find_package(XKBCommon REQUIRED) find_package(Udev REQUIRED) +find_package(Libcap REQUIRED) find_package(Systemd) include(Wayland) diff --git a/session/CMakeLists.txt b/session/CMakeLists.txt index 23077c12..72ef9f56 100644 --- a/session/CMakeLists.txt +++ b/session/CMakeLists.txt @@ -1,5 +1,7 @@ include_directories( - ${WAYLAND_INCLUDE_DIR} + ${WAYLAND_INCLUDE_DIR} + ${DRM_INCLUDE_DIRS} + ${Libcap_INCLUDE_DIRS} ) set(sources @@ -10,6 +12,7 @@ set(sources set(libs wlr-util ${WAYLAND_LIBRARIES} + ${Libcap_LIBRARIES} ) if (SYSTEMD_FOUND) diff --git a/session/direct.c b/session/direct.c index 74f2faf1..e128658a 100644 --- a/session/direct.c +++ b/session/direct.c @@ -5,36 +5,174 @@ #include #include #include +#include +#include +#include +#include +#include +#include +#include +#include #include +#include #include #include +#ifndef KDSKBMUTE +#define KDSKBMUTE 0x4B51 +#endif + +enum { DRM_MAJOR = 226 }; + const struct session_impl session_direct; struct direct_session { struct wlr_session base; + int tty_fd; + int drm_fd; + int kb_mode; + + struct wl_event_source *vt_source; }; static int direct_session_open(struct wlr_session *restrict base, - const char *restrict path) { - return open(path, O_RDWR | O_CLOEXEC); + const char *restrict path) { + struct direct_session *session = wl_container_of(base, session, base); + int fd = open(path, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK); + if (fd == -1) { + wlr_log_errno(L_ERROR, "%s", path); + return -errno; + } + + struct stat st; + if (fstat(fd, &st) == 0 && major(st.st_rdev) == DRM_MAJOR) { + session->drm_fd = fd; + drmSetMaster(fd); + } + + return fd; } static void direct_session_close(struct wlr_session *base, int fd) { + struct direct_session *session = wl_container_of(base, session, base); + + if (fd == session->drm_fd) { + drmDropMaster(fd); + session->drm_fd = -1; + } + close(fd); } static bool direct_change_vt(struct wlr_session *base, int vt) { - // TODO - return false; + struct direct_session *session = wl_container_of(base, session, base); + return ioctl(session->tty_fd, VT_ACTIVATE, vt) == 0; } static void direct_session_finish(struct wlr_session *base) { struct direct_session *session = wl_container_of(base, session, base); + struct vt_mode mode = { + .mode = VT_AUTO, + }; + if (ioctl(session->tty_fd, KDSKBMUTE, 0)) { + ioctl(session->tty_fd, KDSKBMODE, session->kb_mode); + } + ioctl(session->tty_fd, KDSETMODE, KD_TEXT); + ioctl(session->tty_fd, VT_SETMODE, &mode); + + wl_event_source_remove(session->vt_source); + close(session->tty_fd); free(session); } +static int vt_handler(int signo, void *data) { + struct direct_session *session = data; + + if (session->base.active) { + session->base.active = false; + wl_signal_emit(&session->base.session_signal, session); + drmDropMaster(session->drm_fd); + ioctl(session->tty_fd, VT_RELDISP, 1); + } else { + ioctl(session->tty_fd, VT_RELDISP, VT_ACKACQ); + drmSetMaster(session->drm_fd); + session->base.active = true; + wl_signal_emit(&session->base.session_signal, session); + } + + return 1; +} + +static bool setup_tty(struct direct_session *session, struct wl_display *display) { + session->tty_fd = dup(STDIN_FILENO); + + struct stat st; + if (fstat(session->tty_fd, &st) == -1 || major(st.st_rdev) != TTY_MAJOR || + minor(st.st_rdev) == 0) { + wlr_log(L_ERROR, "Not running from a virtual terminal"); + goto error; + } + + int ret; + + int kd_mode; + ret = ioctl(session->tty_fd, KDGETMODE, &kd_mode); + if (ret) { + wlr_log_errno(L_ERROR, "Failed to get tty mode"); + goto error; + } + + if (kd_mode != KD_TEXT) { + wlr_log(L_ERROR, + "tty already in graphics mode; is another display server running?"); + goto error; + } + + ioctl(session->tty_fd, VT_ACTIVATE, minor(st.st_rdev)); + ioctl(session->tty_fd, VT_WAITACTIVE, minor(st.st_rdev)); + + if (ioctl(session->tty_fd, KDGKBMODE, &session->kb_mode)) { + wlr_log_errno(L_ERROR, "Failed to read keyboard mode"); + goto error; + } + + if (ioctl(session->tty_fd, KDSKBMUTE, 1) && + ioctl(session->tty_fd, KDSKBMODE, K_OFF)) { + wlr_log_errno(L_ERROR, "Failed to set keyboard mode"); + goto error; + } + + if (ioctl(session->tty_fd, KDSETMODE, KD_GRAPHICS)) { + wlr_log_errno(L_ERROR, "Failed to get graphics mode on tty"); + goto error; + } + + struct vt_mode mode = { + .mode = VT_PROCESS, + .relsig = SIGUSR1, + .acqsig = SIGUSR1, + }; + + if (ioctl(session->tty_fd, VT_SETMODE, &mode) < 0) { + wlr_log(L_ERROR, "Failed to take control of tty"); + goto error; + } + + struct wl_event_loop *loop = wl_display_get_event_loop(display); + session->vt_source = wl_event_loop_add_signal(loop, SIGUSR1, + vt_handler, session); + if (!session->vt_source) { + goto error; + } + + return true; + +error: + close(session->tty_fd); + return false; +} + static struct wlr_session *direct_session_start(struct wl_display *disp) { struct direct_session *session = calloc(1, sizeof(*session)); if (!session) { @@ -42,12 +180,31 @@ static struct wlr_session *direct_session_start(struct wl_display *disp) { return NULL; } + cap_t cap = cap_get_proc(); + cap_flag_value_t val; + + if (!cap || cap_get_flag(cap, CAP_SYS_ADMIN, CAP_PERMITTED, &val) || val != CAP_SET) { + wlr_log(L_ERROR, "Do not have CAP_SYS_ADMIN; cannot become DRM master"); + cap_free(cap); + goto error_session; + } + + cap_free(cap); + + if (!setup_tty(session, disp)) { + goto error_session; + } + wlr_log(L_INFO, "Successfully loaded direct session"); session->base.impl = &session_direct; session->base.active = true; wl_signal_init(&session->base.session_signal); return &session->base; + +error_session: + free(session); + return NULL; } const struct session_impl session_direct = {