Index: head/lib/libcasper/libcasper/libcasper.3 =================================================================== --- head/lib/libcasper/libcasper/libcasper.3 (revision 350427) +++ head/lib/libcasper/libcasper/libcasper.3 (revision 350428) @@ -1,283 +1,280 @@ .\" Copyright (c) 2013 The FreeBSD Foundation .\" Copyright (c) 2018 Mariusz Zaborski .\" All rights reserved. .\" .\" This documentation was written by Pawel Jakub Dawidek under sponsorship .\" from the FreeBSD Foundation. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $FreeBSD$ .\" -.Dd November 5, 2018 +.Dd July 29, 2019 .Dt LIBCASPER 3 .Os .Sh NAME .Nm cap_init , .Nm cap_wrap , .Nm cap_unwrap , .Nm cap_sock , .Nm cap_clone , .Nm cap_close , .Nm cap_limit_get , .Nm cap_limit_set , .Nm cap_send_nvlist , .Nm cap_recv_nvlist , .Nm cap_xfer_nvlist , .Nm cap_service_open .Nd "library for handling application capabilities" .Sh LIBRARY .Lb libcasper .Sh SYNOPSIS .Fd #define WITH_CASPER .In sys/nv.h .In libcasper.h .Ft "cap_channel_t *" .Fn cap_init "void" .Ft "cap_channel_t *" .Fn cap_wrap "int sock" "int flags" .Ft "int" .Fn cap_unwrap "cap_channel_t *chan" "int *flags" .Ft "int" .Fn cap_sock "const cap_channel_t *chan" .Ft "cap_channel_t *" .Fn cap_clone "const cap_channel_t *chan" .Ft "void" .Fn cap_close "cap_channel_t *chan" .Ft "int" .Fn cap_limit_get "const cap_channel_t *chan" "nvlist_t **limitsp" .Ft "int" .Fn cap_limit_set "const cap_channel_t *chan" "nvlist_t *limits" .Ft "int" .Fn cap_send_nvlist "const cap_channel_t *chan" "const nvlist_t *nvl" .Ft "nvlist_t *" .Fn cap_recv_nvlist "const cap_channel_t *chan" .Ft "nvlist_t *" .Fn cap_xfer_nvlist "const cap_channel_t *chan" "nvlist_t *nvl" .Ft "cap_channel_t *" .Fn cap_service_open "const cap_channel_t *chan" "const char *name" .Sh DESCRIPTION The .Nm libcasper library allows to manage application capabilities through the casper process. .Pp The application capability (represented by the .Vt cap_channel_t type) is a communication channel between the caller and the casper process daemon or an instance of one of its services. A capability to the casper process obtained with the .Fn cap_init function allows to create capabilities to casper's services via the .Fn cap_service_open function. .Pp The .Fn cap_init function opens capability to the casper process. .Pp The .Fn cap_wrap function creates .Vt cap_channel_t based on the given socket. The function is used when capability is inherited through .Xr execve 2 or send over .Xr unix 4 domain socket as a regular file descriptor and has to be represented as .Vt cap_channel_t again. The .Fa flags argument defines the channel behavior. The supported flags are: .Bl -ohang -offset indent .It CASPER_NO_UNIQ The communication between process and casper uses no unique version of nvlist. .El .Pp The .Fn cap_unwrap function is the opposite of the .Fn cap_wrap function. It frees the .Vt cap_channel_t structure and returns .Xr unix 4 domain socket associated with it. .Pp The .Fn cap_clone function clones the given capability. .Pp The .Fn cap_close function closes the given capability. .Pp The .Fn cap_sock function returns .Xr unix 4 domain socket descriptor associated with the given capability for use with system calls like .Xr kevent 2 , .Xr poll 2 and .Xr select 2 . .Pp The .Fn cap_limit_get function stores current limits of the given capability in the .Fa limitsp argument. If the function return .Va 0 and .Dv NULL is stored in .Fa limitsp it means there are no limits set. .Pp The .Fn cap_limit_set function sets limits for the given capability. The limits are provided as a .Xr nvlist 9 . The exact format depends on the service the capability represents. .Fn cap_limit_set frees the limits regardless of whether the operation succeeds or fails. .Pp The .Fn cap_send_nvlist function sends the given .Xr nvlist 9 over the given capability. This is low level interface to communicate with casper services. Most services should provide higher level API. .Pp The .Fn cap_recv_nvlist function receives the given .Xr nvlist 9 over the given capability. .Pp The .Fn cap_xfer_nvlist function sends the given .Xr nvlist 9 , destroys it and receives new .Xr nvlist 9 in response over the given capability. It does not matter if the function succeeds or fails, the .Xr nvlist 9 given for sending will always be destroyed once the function returns. .Pp The .Fn cap_service_open function opens casper service of the given name through casper capability obtained via the .Fn cap_init function. The function returns capability that provides access to opened service. Casper supports the following services in the base system: .Bl -tag -width "system.random" -compact -offset indent .Pp .It system.dns provides DNS libc compatible API .It system.grp provides .Xr getgrent 3 compatible API .It system.pwd provides .Xr getpwent 3 compatible API -.It system.random -allows to obtain entropy from -.Pa /dev/random .It system.sysctl provides .Xr sysctlbyname 3 compatible API .It system.syslog provides .Xr syslog 3 compatible API .Sh RETURN VALUES The .Fn cap_clone , .Fn cap_init , .Fn cap_recv_nvlist , .Fn cap_service_open , .Fn cap_wrap and .Fn cap_xfer_nvlist functions return .Dv NULL and set the .Va errno variable on failure. .Pp The .Fn cap_limit_get , .Fn cap_limit_set and .Fn cap_send_nvlist functions return .Dv -1 and set the .Va errno variable on failure. .Pp The .Fn cap_close , .Fn cap_sock and .Fn cap_unwrap functions always succeed. .Sh SEE ALSO .Xr errno 2 , .Xr execve 2 , .Xr kevent 2 , .Xr poll 2 , .Xr select 2 , .Xr cap_dns 3 , .Xr cap_grp 3 , .Xr cap_pwd 3 , .Xr cap_sysctl 3 , .Xr cap_syslog 3 , .Xr libcasper_service 3 , .Xr capsicum 4 , .Xr unix 4 , .Xr nv 9 .Sh AUTHORS The .Nm libcasper library was implemented by .An Pawel Jakub Dawidek Aq Mt pawel@dawidek.net under sponsorship from the FreeBSD Foundation. The .Nm libcasper new architecture was implemented by .An Mariusz Zaborski Aq Mt oshogbo@FreeBSD.org .