From: Lennart Poettering Date: Wed, 22 Jan 2020 17:05:17 +0100 Subject: sd-bus: introduce API for re-enqueuing incoming messages When authorizing via PolicyKit we want to process incoming method calls twice: once to process and figure out that we need PK authentication, and a second time after we acquired PK authentication to actually execute the operation. With this new call sd_bus_enqueue_for_read() we have a way to put an incoming message back into the read queue for this purpose. This might have other uses too, for example debugging. (cherry picked from commit 1068447e6954dc6ce52f099ed174c442cb89ed54) zjs: patch modified to not make the function public (cherry picked from commit 83bfc0d8dd026814d23e3fdfa46806394f775526) (cherry picked from commit 2e504c92d195d407cec3ba9ed156b195c31a5f3f) (cherry picked from commit 351627d4bfa39dd05f28d889967383af2372de6d) --- src/libsystemd/sd-bus/bus-message.h | 1 + src/libsystemd/sd-bus/sd-bus.c | 24 ++++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/src/libsystemd/sd-bus/bus-message.h b/src/libsystemd/sd-bus/bus-message.h index 0115437..7fd3f11 100644 --- a/src/libsystemd/sd-bus/bus-message.h +++ b/src/libsystemd/sd-bus/bus-message.h @@ -211,3 +211,4 @@ int bus_message_remarshal(sd_bus *bus, sd_bus_message **m); void bus_message_set_sender_driver(sd_bus *bus, sd_bus_message *m); void bus_message_set_sender_local(sd_bus *bus, sd_bus_message *m); +int sd_bus_enqeue_for_read(sd_bus *bus, sd_bus_message *m); diff --git a/src/libsystemd/sd-bus/sd-bus.c b/src/libsystemd/sd-bus/sd-bus.c index 1ff858f..94380af 100644 --- a/src/libsystemd/sd-bus/sd-bus.c +++ b/src/libsystemd/sd-bus/sd-bus.c @@ -4144,3 +4144,27 @@ _public_ int sd_bus_get_close_on_exit(sd_bus *bus) { return bus->close_on_exit; } + +int sd_bus_enqeue_for_read(sd_bus *bus, sd_bus_message *m) { + int r; + + assert_return(bus, -EINVAL); + assert_return(bus = bus_resolve(bus), -ENOPKG); + assert_return(m, -EINVAL); + assert_return(m->sealed, -EINVAL); + assert_return(!bus_pid_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + /* Re-enqeue a message for reading. This is primarily useful for PolicyKit-style authentication, + * where we want accept a message, then determine we need to interactively authenticate the user, and + * when we have that process the message again. */ + + r = bus_rqueue_make_room(bus); + if (r < 0) + return r; + + bus->rqueue[bus->rqueue_size++] = sd_bus_message_ref(m); + return 0; +}