Andrew Geissler | 6ce62a2 | 2020-11-30 19:58:47 -0600 | [diff] [blame] | 1 | From 150d9cade6d475570395cb418b824524dead9577 Mon Sep 17 00:00:00 2001 |
| 2 | From: Joshua Watt <JPEWhacker@gmail.com> |
| 3 | Date: Fri, 30 Oct 2020 08:15:43 -0500 |
| 4 | Subject: [PATCH] logind: Restore chvt as non-root user without polkit |
| 5 | |
| 6 | 4acf0cfd2f ("logind: check PolicyKit before allowing VT switch") broke |
| 7 | the ability to write user sessions that run graphical sessions (e.g. |
| 8 | weston/X11). This was partially amended in 19bb87fbfa ("login: allow |
| 9 | non-console sessions to change vt") by changing the default PolicyKit |
| 10 | policy so that non-root users are again allowed to switch the VT. This |
| 11 | makes the policy when PolKit is not enabled (as on many embedded |
| 12 | systems) match the default PolKit policy and allows launching graphical |
| 13 | sessions as a non-root user. |
| 14 | |
| 15 | Closes #17473 |
| 16 | --- |
| 17 | src/login/logind-dbus.c | 11 ++------- |
| 18 | src/login/logind-polkit.c | 26 +++++++++++++++++++++ |
| 19 | src/login/logind-polkit.h | 10 ++++++++ |
| 20 | src/login/logind-seat-dbus.c | 41 ++++----------------------------- |
| 21 | src/login/logind-session-dbus.c | 11 ++------- |
| 22 | src/login/meson.build | 1 + |
| 23 | 6 files changed, 46 insertions(+), 54 deletions(-) |
| 24 | create mode 100644 src/login/logind-polkit.c |
| 25 | create mode 100644 src/login/logind-polkit.h |
| 26 | |
| 27 | diff --git a/src/login/logind-dbus.c b/src/login/logind-dbus.c |
| 28 | index 0f83ed99bc..a3765d88ba 100644 |
| 29 | --- a/src/login/logind-dbus.c |
| 30 | +++ b/src/login/logind-dbus.c |
| 31 | @@ -30,6 +30,7 @@ |
| 32 | #include "format-util.h" |
| 33 | #include "fs-util.h" |
| 34 | #include "logind-dbus.h" |
| 35 | +#include "logind-polkit.h" |
| 36 | #include "logind-seat-dbus.h" |
| 37 | #include "logind-session-dbus.h" |
| 38 | #include "logind-user-dbus.h" |
| 39 | @@ -1047,15 +1048,7 @@ static int method_activate_session_on_seat(sd_bus_message *message, void *userda |
| 40 | return sd_bus_error_setf(error, BUS_ERROR_SESSION_NOT_ON_SEAT, |
| 41 | "Session %s not on seat %s", session_name, seat_name); |
| 42 | |
| 43 | - r = bus_verify_polkit_async( |
| 44 | - message, |
| 45 | - CAP_SYS_ADMIN, |
| 46 | - "org.freedesktop.login1.chvt", |
| 47 | - NULL, |
| 48 | - false, |
| 49 | - UID_INVALID, |
| 50 | - &m->polkit_registry, |
| 51 | - error); |
| 52 | + r = check_polkit_chvt(message, m, error); |
| 53 | if (r < 0) |
| 54 | return r; |
| 55 | if (r == 0) |
| 56 | diff --git a/src/login/logind-polkit.c b/src/login/logind-polkit.c |
| 57 | new file mode 100644 |
| 58 | index 0000000000..9072570cc6 |
| 59 | --- /dev/null |
| 60 | +++ b/src/login/logind-polkit.c |
| 61 | @@ -0,0 +1,26 @@ |
| 62 | +/* SPDX-License-Identifier: LGPL-2.1+ */ |
| 63 | + |
| 64 | +#include "bus-polkit.h" |
| 65 | +#include "logind-polkit.h" |
| 66 | +#include "missing_capability.h" |
| 67 | +#include "user-util.h" |
| 68 | + |
| 69 | +int check_polkit_chvt(sd_bus_message *message, Manager *manager, sd_bus_error *error) { |
| 70 | +#if ENABLE_POLKIT |
| 71 | + return bus_verify_polkit_async( |
| 72 | + message, |
| 73 | + CAP_SYS_ADMIN, |
| 74 | + "org.freedesktop.login1.chvt", |
| 75 | + NULL, |
| 76 | + false, |
| 77 | + UID_INVALID, |
| 78 | + &manager->polkit_registry, |
| 79 | + error); |
| 80 | +#else |
| 81 | + /* Allow chvt when polkit is not present. This allows a service to start a graphical session as a |
| 82 | + * non-root user when polkit is not compiled in, matching the default polkit policy */ |
| 83 | + return 1; |
| 84 | +#endif |
| 85 | +} |
| 86 | + |
| 87 | + |
| 88 | diff --git a/src/login/logind-polkit.h b/src/login/logind-polkit.h |
| 89 | new file mode 100644 |
| 90 | index 0000000000..476c077a8a |
| 91 | --- /dev/null |
| 92 | +++ b/src/login/logind-polkit.h |
| 93 | @@ -0,0 +1,10 @@ |
| 94 | +/* SPDX-License-Identifier: LGPL-2.1+ */ |
| 95 | +#pragma once |
| 96 | + |
| 97 | +#include "sd-bus.h" |
| 98 | + |
| 99 | +#include "bus-object.h" |
| 100 | +#include "logind.h" |
| 101 | + |
| 102 | +int check_polkit_chvt(sd_bus_message *message, Manager *manager, sd_bus_error *error); |
| 103 | + |
| 104 | diff --git a/src/login/logind-seat-dbus.c b/src/login/logind-seat-dbus.c |
| 105 | index a945132284..f22e9e2734 100644 |
| 106 | --- a/src/login/logind-seat-dbus.c |
| 107 | +++ b/src/login/logind-seat-dbus.c |
| 108 | @@ -9,6 +9,7 @@ |
| 109 | #include "bus-polkit.h" |
| 110 | #include "bus-util.h" |
| 111 | #include "logind-dbus.h" |
| 112 | +#include "logind-polkit.h" |
| 113 | #include "logind-seat-dbus.h" |
| 114 | #include "logind-seat.h" |
| 115 | #include "logind-session-dbus.h" |
| 116 | @@ -179,15 +180,7 @@ static int method_activate_session(sd_bus_message *message, void *userdata, sd_b |
| 117 | if (session->seat != s) |
| 118 | return sd_bus_error_setf(error, BUS_ERROR_SESSION_NOT_ON_SEAT, "Session %s not on seat %s", name, s->id); |
| 119 | |
| 120 | - r = bus_verify_polkit_async( |
| 121 | - message, |
| 122 | - CAP_SYS_ADMIN, |
| 123 | - "org.freedesktop.login1.chvt", |
| 124 | - NULL, |
| 125 | - false, |
| 126 | - UID_INVALID, |
| 127 | - &s->manager->polkit_registry, |
| 128 | - error); |
| 129 | + r = check_polkit_chvt(message, s->manager, error); |
| 130 | if (r < 0) |
| 131 | return r; |
| 132 | if (r == 0) |
| 133 | @@ -215,15 +208,7 @@ static int method_switch_to(sd_bus_message *message, void *userdata, sd_bus_erro |
| 134 | if (to <= 0) |
| 135 | return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid virtual terminal"); |
| 136 | |
| 137 | - r = bus_verify_polkit_async( |
| 138 | - message, |
| 139 | - CAP_SYS_ADMIN, |
| 140 | - "org.freedesktop.login1.chvt", |
| 141 | - NULL, |
| 142 | - false, |
| 143 | - UID_INVALID, |
| 144 | - &s->manager->polkit_registry, |
| 145 | - error); |
| 146 | + r = check_polkit_chvt(message, s->manager, error); |
| 147 | if (r < 0) |
| 148 | return r; |
| 149 | if (r == 0) |
| 150 | @@ -243,15 +228,7 @@ static int method_switch_to_next(sd_bus_message *message, void *userdata, sd_bus |
| 151 | assert(message); |
| 152 | assert(s); |
| 153 | |
| 154 | - r = bus_verify_polkit_async( |
| 155 | - message, |
| 156 | - CAP_SYS_ADMIN, |
| 157 | - "org.freedesktop.login1.chvt", |
| 158 | - NULL, |
| 159 | - false, |
| 160 | - UID_INVALID, |
| 161 | - &s->manager->polkit_registry, |
| 162 | - error); |
| 163 | + r = check_polkit_chvt(message, s->manager, error); |
| 164 | if (r < 0) |
| 165 | return r; |
| 166 | if (r == 0) |
| 167 | @@ -271,15 +248,7 @@ static int method_switch_to_previous(sd_bus_message *message, void *userdata, sd |
| 168 | assert(message); |
| 169 | assert(s); |
| 170 | |
| 171 | - r = bus_verify_polkit_async( |
| 172 | - message, |
| 173 | - CAP_SYS_ADMIN, |
| 174 | - "org.freedesktop.login1.chvt", |
| 175 | - NULL, |
| 176 | - false, |
| 177 | - UID_INVALID, |
| 178 | - &s->manager->polkit_registry, |
| 179 | - error); |
| 180 | + r = check_polkit_chvt(message, s->manager, error); |
| 181 | if (r < 0) |
| 182 | return r; |
| 183 | if (r == 0) |
| 184 | diff --git a/src/login/logind-session-dbus.c b/src/login/logind-session-dbus.c |
| 185 | index ccc5ac8df2..57c8a4e900 100644 |
| 186 | --- a/src/login/logind-session-dbus.c |
| 187 | +++ b/src/login/logind-session-dbus.c |
| 188 | @@ -11,6 +11,7 @@ |
| 189 | #include "fd-util.h" |
| 190 | #include "logind-brightness.h" |
| 191 | #include "logind-dbus.h" |
| 192 | +#include "logind-polkit.h" |
| 193 | #include "logind-seat-dbus.h" |
| 194 | #include "logind-session-dbus.h" |
| 195 | #include "logind-session-device.h" |
| 196 | @@ -192,15 +193,7 @@ int bus_session_method_activate(sd_bus_message *message, void *userdata, sd_bus_ |
| 197 | assert(message); |
| 198 | assert(s); |
| 199 | |
| 200 | - r = bus_verify_polkit_async( |
| 201 | - message, |
| 202 | - CAP_SYS_ADMIN, |
| 203 | - "org.freedesktop.login1.chvt", |
| 204 | - NULL, |
| 205 | - false, |
| 206 | - UID_INVALID, |
| 207 | - &s->manager->polkit_registry, |
| 208 | - error); |
| 209 | + r = check_polkit_chvt(message, s->manager, error); |
| 210 | if (r < 0) |
| 211 | return r; |
| 212 | if (r == 0) |
| 213 | diff --git a/src/login/meson.build b/src/login/meson.build |
| 214 | index 0a7d3d5440..7e46be2add 100644 |
| 215 | --- a/src/login/meson.build |
| 216 | +++ b/src/login/meson.build |
| 217 | @@ -26,6 +26,7 @@ liblogind_core_sources = files(''' |
| 218 | logind-device.h |
| 219 | logind-inhibit.c |
| 220 | logind-inhibit.h |
| 221 | + logind-polkit.c |
| 222 | logind-seat-dbus.c |
| 223 | logind-seat-dbus.h |
| 224 | logind-seat.c |
| 225 | -- |
| 226 | 2.28.0 |
| 227 | |