mirror of
https://git.pwmt.org/pwmt/zathura.git
synced 2025-01-04 03:45:59 +01:00
seccomp implementation
This commit is contained in:
parent
3093c7955e
commit
4bde3d793f
6 changed files with 613 additions and 0 deletions
4
Makefile
4
Makefile
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@ -23,6 +23,10 @@ ifneq ($(WITH_SYNCTEX),0)
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CPPFLAGS += -DWITH_SYNCTEX
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CPPFLAGS += -DWITH_SYNCTEX
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endif
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endif
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ifneq ($(WITH_SECCOMP),0)
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CPPFLAGS += -DWITH_SECCOMP
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endif
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ifneq ($(wildcard ${VALGRIND_SUPPRESSION_FILE}),)
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ifneq ($(wildcard ${VALGRIND_SUPPRESSION_FILE}),)
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VALGRIND_ARGUMENTS += --suppressions=${VALGRIND_SUPPRESSION_FILE}
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VALGRIND_ARGUMENTS += --suppressions=${VALGRIND_SUPPRESSION_FILE}
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endif
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endif
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12
config.mk
12
config.mk
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@ -47,6 +47,10 @@ WITH_SYNCTEX ?= $(shell (${PKG_CONFIG} synctex && echo 1) || echo 0)
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# To disable support for mimetype detction with libmagic set WITH_MAGIC to 0.
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# To disable support for mimetype detction with libmagic set WITH_MAGIC to 0.
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WITH_MAGIC ?= 1
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WITH_MAGIC ?= 1
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# seccomp
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# To enable support for seccomp filter set WITH_SECCOMP to 1.
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WITH_SECCOMP ?= 0
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# paths
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# paths
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PREFIX ?= /usr
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PREFIX ?= /usr
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MANPREFIX ?= ${PREFIX}/share/man
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MANPREFIX ?= ${PREFIX}/share/man
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@ -116,6 +120,14 @@ LIBS += ${SYNCTEX_LIB}
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endif
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endif
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endif
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endif
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ifneq (${WITH_SECCOMP},0)
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SECCOMP_INC ?=
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SECCOMP_LIB ?= -lseccomp
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INCS += ${SECCOMP_INC}
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LIBS += ${SECCOMP_LIB}
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endif
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ifneq (${PKG_CONFIG_LIBS},)
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ifneq (${PKG_CONFIG_LIBS},)
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INCS += $(shell ${PKG_CONFIG} --cflags ${PKG_CONFIG_LIBS})
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INCS += $(shell ${PKG_CONFIG} --cflags ${PKG_CONFIG_LIBS})
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LIBS += $(shell ${PKG_CONFIG} --libs ${PKG_CONFIG_LIBS})
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LIBS += $(shell ${PKG_CONFIG} --libs ${PKG_CONFIG_LIBS})
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554
zathura/libsec.c
Normal file
554
zathura/libsec.c
Normal file
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@ -0,0 +1,554 @@
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#include "libsec.h"
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#include <stdio.h>
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#ifdef WITH_SECCOMP
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#include <seccomp.h> /* libseccomp */
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#include <sys/prctl.h> /* prctl */
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#include <sys/socket.h>
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#include <fcntl.h>
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#include <stdlib.h>
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#include <errno.h>
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#define DENY_RULE(call) { if (seccomp_rule_add (ctx, SCMP_ACT_KILL, SCMP_SYS(call), 0) < 0) goto out; }
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#define ALLOW_RULE(call) { if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(call), 0) < 0) goto out; }
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scmp_filter_ctx ctx;
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int protectedMode(void){
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/* prevent child processes from getting more priv e.g. via setuid, capabilities, ... */
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if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
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perror("prctl SET_NO_NEW_PRIVS");
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exit(EXIT_FAILURE);
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}
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/* prevent escape via ptrace */
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if(prctl (PR_SET_DUMPABLE, 0, 0, 0, 0)){
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perror("prctl PR_SET_DUMPABLE");
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exit(EXIT_FAILURE);
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}
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/* initialize the filter */
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ctx = seccomp_init(SCMP_ACT_ALLOW);
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if (ctx == NULL){
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perror("seccomp_init failed");
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exit(EXIT_FAILURE);
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}
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DENY_RULE (_sysctl);
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DENY_RULE (acct);
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DENY_RULE (add_key);
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DENY_RULE (adjtimex);
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DENY_RULE (chroot);
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DENY_RULE (clock_adjtime);
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DENY_RULE (create_module);
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DENY_RULE (delete_module);
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DENY_RULE (fanotify_init);
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DENY_RULE (finit_module);
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DENY_RULE (get_kernel_syms);
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DENY_RULE (get_mempolicy);
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DENY_RULE (init_module);
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DENY_RULE (io_cancel);
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DENY_RULE (io_destroy);
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DENY_RULE (io_getevents);
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DENY_RULE (io_setup);
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DENY_RULE (io_submit);
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DENY_RULE (ioperm);
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DENY_RULE (iopl);
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DENY_RULE (ioprio_set);
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DENY_RULE (kcmp);
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DENY_RULE (kexec_file_load);
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DENY_RULE (kexec_load);
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DENY_RULE (keyctl);
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DENY_RULE (lookup_dcookie);
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DENY_RULE (mbind);
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DENY_RULE (nfsservctl);
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DENY_RULE (migrate_pages);
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DENY_RULE (modify_ldt);
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DENY_RULE (mount);
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DENY_RULE (move_pages);
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DENY_RULE (name_to_handle_at);
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DENY_RULE (open_by_handle_at);
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DENY_RULE (perf_event_open);
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DENY_RULE (pivot_root);
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DENY_RULE (process_vm_readv);
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DENY_RULE (process_vm_writev);
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DENY_RULE (ptrace);
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DENY_RULE (reboot);
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DENY_RULE (remap_file_pages);
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DENY_RULE (request_key);
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DENY_RULE (set_mempolicy);
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DENY_RULE (swapoff);
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DENY_RULE (swapon);
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DENY_RULE (sysfs);
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DENY_RULE (syslog);
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DENY_RULE (tuxcall);
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DENY_RULE (umount2);
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DENY_RULE (uselib);
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DENY_RULE (vmsplice);
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/* applying filter... */
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if (seccomp_load (ctx) >= 0){
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/* free ctx after the filter has been loaded into the kernel */
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seccomp_release(ctx);
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return 0;
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}
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out:
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/* something went wrong */
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seccomp_release(ctx);
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return 1;
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}
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int protectedView(void){
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/* prevent child processes from getting more priv e.g. via setuid, capabilities, ... */
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if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
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perror("prctl SET_NO_NEW_PRIVS");
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exit(EXIT_FAILURE);
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}
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/* prevent escape via ptrace */
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if(prctl (PR_SET_DUMPABLE, 0, 0, 0, 0)){
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perror("prctl PR_SET_DUMPABLE");
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exit(EXIT_FAILURE);
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}
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/* initialize the filter */
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ctx = seccomp_init(SCMP_ACT_KILL);
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if (ctx == NULL){
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perror("seccomp_init failed");
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exit(EXIT_FAILURE);
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}
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ALLOW_RULE (access);
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ALLOW_RULE (bind);
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ALLOW_RULE (brk);
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ALLOW_RULE (clock_getres);
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ALLOW_RULE (clone);
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ALLOW_RULE (close);
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ALLOW_RULE (connect);
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ALLOW_RULE (eventfd2);
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ALLOW_RULE (exit);
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ALLOW_RULE (exit_group);
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ALLOW_RULE (fadvise64);
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ALLOW_RULE (fallocate);
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ALLOW_RULE (fcntl); /* TODO: build detailed filter */
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ALLOW_RULE (fstat);
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ALLOW_RULE (fstatfs);
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ALLOW_RULE (ftruncate);
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ALLOW_RULE (futex);
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ALLOW_RULE (getdents);
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ALLOW_RULE (getegid);
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ALLOW_RULE (geteuid);
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ALLOW_RULE (getgid);
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ALLOW_RULE (getuid);
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ALLOW_RULE (getpid);
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ALLOW_RULE (getppid);
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ALLOW_RULE (getpgrp);
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ALLOW_RULE (getpeername);
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ALLOW_RULE (getrandom);
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ALLOW_RULE (getresgid);
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ALLOW_RULE (getresuid);
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ALLOW_RULE (getrlimit);
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ALLOW_RULE (getsockname);
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ALLOW_RULE (getsockopt); /* needed for access to x11 socket in network namespace (without abstract sockets) */
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ALLOW_RULE (inotify_add_watch);
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ALLOW_RULE (inotify_init1);
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ALLOW_RULE (inotify_rm_watch);
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/* ALLOW_RULE (ioctl); specified below */
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ALLOW_RULE (lseek);
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ALLOW_RULE (lstat);
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ALLOW_RULE (madvise);
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ALLOW_RULE (memfd_create);
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ALLOW_RULE (mkdir); /* needed for first run only */
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ALLOW_RULE (mmap);
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ALLOW_RULE (mprotect);
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ALLOW_RULE (mremap);
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ALLOW_RULE (munmap);
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ALLOW_RULE (open); /* (zathura needs to open for writing) TODO: avoid needing this somehow */
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ALLOW_RULE (openat);
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ALLOW_RULE (pipe);
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ALLOW_RULE (poll);
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ALLOW_RULE (pwrite64); /* TODO: build detailed filter */
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ALLOW_RULE (pread64);
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ALLOW_RULE (prlimit64);
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ALLOW_RULE (prctl); /* NOT specified below */
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ALLOW_RULE (read);
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ALLOW_RULE (readlink);
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ALLOW_RULE (recvfrom);
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ALLOW_RULE (recvmsg);
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ALLOW_RULE (restart_syscall);
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ALLOW_RULE (rt_sigaction);
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ALLOW_RULE (rt_sigprocmask);
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ALLOW_RULE (seccomp);
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ALLOW_RULE (sendmsg);
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ALLOW_RULE (sendto);
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ALLOW_RULE (select);
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ALLOW_RULE (set_robust_list);
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ALLOW_RULE (setsockopt);
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ALLOW_RULE (shmat);
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ALLOW_RULE (shmctl);
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ALLOW_RULE (shmdt);
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ALLOW_RULE (shmget);
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ALLOW_RULE (shutdown);
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ALLOW_RULE (stat);
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ALLOW_RULE (statfs);
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/* ALLOW_RULE (socket); specified below */
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ALLOW_RULE (sysinfo);
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ALLOW_RULE (uname);
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ALLOW_RULE (unlink);
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ALLOW_RULE (write); /* specified below (zathura needs to write files)*/
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ALLOW_RULE (writev);
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ALLOW_RULE (wait4); /* trying to open links should not crash the app */
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/* allowed for use with container */
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ALLOW_RULE (chmod);
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ALLOW_RULE (link);
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ALLOW_RULE (rename);
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/* allowed for debugging: */
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/* ALLOW_RULE (prctl); */
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/* ALLOW_RULE (ioctl); */
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/* incomplete */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, F_GETFL)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, F_SETFL)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, F_SETFD)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, F_GETFD)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, F_SETLK)) < 0) */
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/* goto out; */
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/* Special requirements for ioctl, allowed on stdout/stderr */
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if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(ioctl), 1,
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SCMP_CMP(0, SCMP_CMP_EQ, 1)) < 0)
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goto out;
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if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(ioctl), 1,
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SCMP_CMP(0, SCMP_CMP_EQ, 2)) < 0)
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goto out;
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|
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|
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/* TODO: build detailed filter for prctl */
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/* needed by gtk??? (does not load content without) */
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/* /\* special restrictions for prctl, only allow PR_SET_NAME/PR_SET_PDEATHSIG *\/ */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(prctl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, PR_SET_NAME)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(prctl), 1, */
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/* SCMP_CMP(0, SCMP_CMP_EQ, PR_SET_PDEATHSIG)) < 0) */
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/* goto out; */
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|
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|
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|
|
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/* when zathura is run on wayland, with X11 server available but blocked, unset the DISPLAY variable */
|
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/* otherwise it will try to connect to X11 using inet socket protocol */
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|
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/* required changes in links.c (at girara_xdg_open) */
|
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/* special restrictions for socket, only allow AF_UNIX/AF_LOCAL */
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if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(socket), 1,
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SCMP_CMP(0, SCMP_CMP_EQ, AF_UNIX)) < 0)
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goto out;
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if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(socket), 1,
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SCMP_CMP(0, SCMP_CMP_EQ, AF_LOCAL)) < 0)
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goto out;
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|
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|
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/* TODO: avoid the need for the open syscall to be allowed with write permissions */
|
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/* zathura needs to open files for writing to save current position */
|
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/* /\* special restrictions for open, prevent opening files for writing *\/ */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(open), 1, */
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/* SCMP_CMP(1, SCMP_CMP_MASKED_EQ, O_WRONLY | O_RDWR, 0)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ERRNO (EACCES), SCMP_SYS(open), 1, */
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/* SCMP_CMP(1, SCMP_CMP_MASKED_EQ, O_WRONLY, O_WRONLY)) < 0) */
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/* goto out; */
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/* if (seccomp_rule_add (ctx, SCMP_ACT_ERRNO (EACCES), SCMP_SYS(open), 1, */
|
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/* SCMP_CMP(1, SCMP_CMP_MASKED_EQ, O_RDWR, O_RDWR)) < 0) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
/* ------------ experimental filters --------------- */
|
||||||
|
|
||||||
|
|
||||||
|
/* /\* this filter is susceptible to TOCTOU race conditions, providing limited use *\/ */
|
||||||
|
/* /\* allow opening only specified files identified by their file descriptors*\/ */
|
||||||
|
|
||||||
|
/* this requires either a list of all files to open (A LOT!!!) */
|
||||||
|
/* or needs to be applied only after initialisation, right before parsing */
|
||||||
|
/* if(seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(read), 1, */
|
||||||
|
/* SCMP_CMP(SCMP_CMP_EQ, fd)) < 0) /\* or < 1 ??? *\/ */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
|
||||||
|
/* /\* restricting write access *\/ */
|
||||||
|
|
||||||
|
/* /\* allow stdin *\/ */
|
||||||
|
/* if (seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(write), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_EQ, 0)) < 0 ) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
/* /\* allow stdout *\/ */
|
||||||
|
/* if (seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(write), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_EQ, 1)) < 0 ) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
|
||||||
|
/* /\* allow stderr *\/ */
|
||||||
|
/* if (seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(write), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_EQ, 2)) < 0 ) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
|
||||||
|
/* /\* restrict writev (write a vector) access *\/ */
|
||||||
|
/* this does not seem reliable but it surprisingly is. investigate more */
|
||||||
|
/* if (seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(writev), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_EQ, 3)) < 0 ) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
/* test if repeating this after some time or denying it works */
|
||||||
|
|
||||||
|
|
||||||
|
/* first attempt to filter poll requests */
|
||||||
|
/* if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(poll), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_MASKED_EQ, POLLIN | POLL, 0)) < 0) */
|
||||||
|
/* goto out; */
|
||||||
|
|
||||||
|
|
||||||
|
/* /\* restrict fcntl calls *\/ */
|
||||||
|
/* this syscall sets the file descriptor to read write */
|
||||||
|
/* if (seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(fcntl), 1, */
|
||||||
|
/* SCMP_CMP(0, SCMP_CMP_EQ, 3)) < 0 ) */
|
||||||
|
/* goto out; */
|
||||||
|
/* fcntl(3, F_GETFL) = 0x2 (flags O_RDWR) */
|
||||||
|
/* fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 */
|
||||||
|
/* fcntl(3, F_SETFD, FD_CLOEXEC) = 0 */
|
||||||
|
|
||||||
|
|
||||||
|
/* ------------------ end of experimental filters ------------------ */
|
||||||
|
|
||||||
|
|
||||||
|
/* applying filter... */
|
||||||
|
if (seccomp_load (ctx) >= 0){
|
||||||
|
/* free ctx after the filter has been loaded into the kernel */
|
||||||
|
seccomp_release(ctx);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
out:
|
||||||
|
/* something went wrong */
|
||||||
|
seccomp_release(ctx);
|
||||||
|
return 1;
|
||||||
|
|
||||||
|
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
int strictFilter(void){
|
||||||
|
|
||||||
|
/* prevent child processes from getting more priv e.g. via setuid, capabilities, ... */
|
||||||
|
if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
|
||||||
|
perror("prctl SET_NO_NEW_PRIVS");
|
||||||
|
exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* prevent escape via ptrace */
|
||||||
|
if(prctl (PR_SET_DUMPABLE, 0, 0, 0, 0)){
|
||||||
|
perror("prctl PR_SET_DUMPABLE");
|
||||||
|
exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
|
||||||
|
/* initialize the filter */
|
||||||
|
ctx = seccomp_init(SCMP_ACT_KILL);
|
||||||
|
if (ctx == NULL){
|
||||||
|
perror("seccomp_init failed");
|
||||||
|
exit(EXIT_FAILURE);
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
ALLOW_RULE (access);
|
||||||
|
/* ALLOW_RULE (arch_prctl); */
|
||||||
|
ALLOW_RULE (bind);
|
||||||
|
ALLOW_RULE (brk);
|
||||||
|
ALLOW_RULE (clock_getres);
|
||||||
|
ALLOW_RULE (clone);
|
||||||
|
ALLOW_RULE (close);
|
||||||
|
/* ALLOW_RULE (connect); */
|
||||||
|
ALLOW_RULE (eventfd2);
|
||||||
|
ALLOW_RULE (exit);
|
||||||
|
ALLOW_RULE (exit_group);
|
||||||
|
ALLOW_RULE (fadvise64);
|
||||||
|
ALLOW_RULE (fallocate);
|
||||||
|
ALLOW_RULE (fcntl); /* TODO: build detailed filter */
|
||||||
|
ALLOW_RULE (fstat);
|
||||||
|
ALLOW_RULE (fstatfs);
|
||||||
|
ALLOW_RULE (ftruncate);
|
||||||
|
ALLOW_RULE (futex);
|
||||||
|
ALLOW_RULE (getdents);
|
||||||
|
ALLOW_RULE (getegid);
|
||||||
|
ALLOW_RULE (geteuid);
|
||||||
|
ALLOW_RULE (getgid);
|
||||||
|
ALLOW_RULE (getuid);
|
||||||
|
ALLOW_RULE (getpid);
|
||||||
|
/* ALLOW_RULE (getpeername); */
|
||||||
|
ALLOW_RULE (getresgid);
|
||||||
|
ALLOW_RULE (getresuid);
|
||||||
|
ALLOW_RULE (getrlimit);
|
||||||
|
/* ALLOW_RULE (getsockname); */
|
||||||
|
/* ALLOW_RULE (getsockopt); needed for access to x11 socket in network namespace (without abstract sockets) */
|
||||||
|
ALLOW_RULE (inotify_add_watch);
|
||||||
|
ALLOW_RULE (inotify_init1);
|
||||||
|
ALLOW_RULE (inotify_rm_watch);
|
||||||
|
/* ALLOW_RULE (ioctl); specified below */
|
||||||
|
ALLOW_RULE (lseek);
|
||||||
|
ALLOW_RULE (lstat);
|
||||||
|
ALLOW_RULE (madvise);
|
||||||
|
ALLOW_RULE (memfd_create);
|
||||||
|
ALLOW_RULE (mkdir); /* needed for first run only */
|
||||||
|
ALLOW_RULE (mmap);
|
||||||
|
ALLOW_RULE (mprotect);
|
||||||
|
ALLOW_RULE (mremap);
|
||||||
|
ALLOW_RULE (munmap);
|
||||||
|
ALLOW_RULE (open); /* (zathura needs to open for writing) TODO: avoid needing this somehow */
|
||||||
|
ALLOW_RULE (openat);
|
||||||
|
ALLOW_RULE (pipe);
|
||||||
|
ALLOW_RULE (poll);
|
||||||
|
ALLOW_RULE (pwrite64); /* TODO: build detailed filter */
|
||||||
|
ALLOW_RULE (pread64);
|
||||||
|
/* ALLOW_RULE (prlimit64); */
|
||||||
|
/* ALLOW_RULE (prctl); specified below */
|
||||||
|
ALLOW_RULE (read);
|
||||||
|
ALLOW_RULE (readlink);
|
||||||
|
ALLOW_RULE (recvfrom);
|
||||||
|
ALLOW_RULE (recvmsg);
|
||||||
|
ALLOW_RULE (restart_syscall);
|
||||||
|
ALLOW_RULE (rt_sigaction);
|
||||||
|
ALLOW_RULE (rt_sigprocmask);
|
||||||
|
ALLOW_RULE (sendmsg);
|
||||||
|
ALLOW_RULE (sendto);
|
||||||
|
ALLOW_RULE (select);
|
||||||
|
ALLOW_RULE (set_robust_list);
|
||||||
|
/* ALLOW_RULE (set_tid_address); */
|
||||||
|
/* ALLOW_RULE (setsockopt); */
|
||||||
|
ALLOW_RULE (shmat);
|
||||||
|
ALLOW_RULE (shmctl);
|
||||||
|
ALLOW_RULE (shmdt);
|
||||||
|
ALLOW_RULE (shmget);
|
||||||
|
ALLOW_RULE (shutdown);
|
||||||
|
ALLOW_RULE (stat);
|
||||||
|
ALLOW_RULE (statfs);
|
||||||
|
/* ALLOW_RULE (socket); */
|
||||||
|
ALLOW_RULE (sysinfo);
|
||||||
|
ALLOW_RULE (uname);
|
||||||
|
ALLOW_RULE (unlink);
|
||||||
|
ALLOW_RULE (write); /* specified below (zathura needs to write files)*/
|
||||||
|
ALLOW_RULE (writev);
|
||||||
|
ALLOW_RULE (wait4); /* trying to open links should not crash the app */
|
||||||
|
|
||||||
|
|
||||||
|
/* Special requirements for ioctl, allowed on stdout/stderr */
|
||||||
|
if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(ioctl), 1,
|
||||||
|
SCMP_CMP(0, SCMP_CMP_EQ, 1)) < 0)
|
||||||
|
goto out;
|
||||||
|
if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(ioctl), 1,
|
||||||
|
SCMP_CMP(0, SCMP_CMP_EQ, 2)) < 0)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
/* needed by gtk??? (does not load content without) */
|
||||||
|
|
||||||
|
/* special restrictions for prctl, only allow PR_SET_NAME/PR_SET_PDEATHSIG */
|
||||||
|
if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(prctl), 1,
|
||||||
|
SCMP_CMP(0, SCMP_CMP_EQ, PR_SET_NAME)) < 0)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
if (seccomp_rule_add (ctx, SCMP_ACT_ALLOW, SCMP_SYS(prctl), 1,
|
||||||
|
SCMP_CMP(0, SCMP_CMP_EQ, PR_SET_PDEATHSIG)) < 0)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
/* allowed for debugging: */
|
||||||
|
|
||||||
|
/* ALLOW_RULE (prctl); */
|
||||||
|
/* ALLOW_RULE (ioctl); */
|
||||||
|
|
||||||
|
|
||||||
|
/* applying filter... */
|
||||||
|
if (seccomp_load (ctx) >= 0){
|
||||||
|
/* free ctx after the filter has been loaded into the kernel */
|
||||||
|
seccomp_release(ctx);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
out:
|
||||||
|
/* something went wrong */
|
||||||
|
seccomp_release(ctx);
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#else /* WITH_SECCOMP */
|
||||||
|
|
||||||
|
int protectedMode(void){
|
||||||
|
|
||||||
|
perror("No seccomp support compiled-in\n");
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
int protectedView(void){
|
||||||
|
|
||||||
|
perror("No seccomp support compiled-in\n");
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
int strictFilter(void){
|
||||||
|
|
||||||
|
perror("No seccomp support compiled-in\n");
|
||||||
|
return 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif /* WITH_SECCOMP */
|
19
zathura/libsec.h
Normal file
19
zathura/libsec.h
Normal file
|
@ -0,0 +1,19 @@
|
||||||
|
#ifndef SECCOMP_H
|
||||||
|
#define SECCOMP_H
|
||||||
|
|
||||||
|
/* basic filter */
|
||||||
|
/* this mode allows normal use */
|
||||||
|
/* only dangerous syscalls are blacklisted */
|
||||||
|
int protectedMode(void);
|
||||||
|
|
||||||
|
/* secure whitelist filter */
|
||||||
|
/* whitelist minimal syscalls only */
|
||||||
|
/* this mode does not allow to open external links or to start applications */
|
||||||
|
/* network connections are prohibited as well */
|
||||||
|
int protectedView(void);
|
||||||
|
|
||||||
|
/* strict filter before document parsing */
|
||||||
|
/* this filter is to be enabled after most of the initialisation of zathura has finished */
|
||||||
|
int strictFilter(void);
|
||||||
|
|
||||||
|
#endif
|
|
@ -14,6 +14,10 @@
|
||||||
#include "page.h"
|
#include "page.h"
|
||||||
#include "render.h"
|
#include "render.h"
|
||||||
|
|
||||||
|
#ifdef WITH_SECCOMP
|
||||||
|
#include "libsec.h"
|
||||||
|
#endif
|
||||||
|
|
||||||
struct zathura_link_s {
|
struct zathura_link_s {
|
||||||
zathura_rectangle_t position; /**< Position of the link */
|
zathura_rectangle_t position; /**< Position of the link */
|
||||||
zathura_link_type_t type; /**< Link type */
|
zathura_link_type_t type; /**< Link type */
|
||||||
|
@ -199,9 +203,14 @@ zathura_link_evaluate(zathura_t* zathura, zathura_link_t* link)
|
||||||
link_remote(zathura, link->target.value);
|
link_remote(zathura, link->target.value);
|
||||||
break;
|
break;
|
||||||
case ZATHURA_LINK_URI:
|
case ZATHURA_LINK_URI:
|
||||||
|
#ifndef WITH_SECCOMP
|
||||||
if (girara_xdg_open(link->target.value) == false) {
|
if (girara_xdg_open(link->target.value) == false) {
|
||||||
girara_notify(zathura->ui.session, GIRARA_ERROR, _("Failed to run xdg-open."));
|
girara_notify(zathura->ui.session, GIRARA_ERROR, _("Failed to run xdg-open."));
|
||||||
}
|
}
|
||||||
|
#endif
|
||||||
|
#ifdef WITH_SECCOMP
|
||||||
|
girara_notify(zathura->ui.session, GIRARA_ERROR, _("Opening external apps in protectedView Sandbox mode is not permitted"));
|
||||||
|
#endif
|
||||||
break;
|
break;
|
||||||
case ZATHURA_LINK_LAUNCH:
|
case ZATHURA_LINK_LAUNCH:
|
||||||
link_launch(zathura, link);
|
link_launch(zathura, link);
|
||||||
|
|
|
@ -19,6 +19,11 @@
|
||||||
#include "synctex.h"
|
#include "synctex.h"
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
#ifdef WITH_SECCOMP
|
||||||
|
#include <unistd.h>
|
||||||
|
#include "libsec.h"
|
||||||
|
#endif
|
||||||
|
|
||||||
/* Init locale */
|
/* Init locale */
|
||||||
static void
|
static void
|
||||||
init_locale(void)
|
init_locale(void)
|
||||||
|
@ -122,6 +127,11 @@ init_zathura(const char* config_dir, const char* data_dir,
|
||||||
int
|
int
|
||||||
main(int argc, char* argv[])
|
main(int argc, char* argv[])
|
||||||
{
|
{
|
||||||
|
|
||||||
|
#ifdef WITH_SECCOMP
|
||||||
|
protectedView();
|
||||||
|
#endif
|
||||||
|
|
||||||
init_locale();
|
init_locale();
|
||||||
|
|
||||||
/* parse command line arguments */
|
/* parse command line arguments */
|
||||||
|
@ -288,6 +298,11 @@ main(int argc, char* argv[])
|
||||||
goto free_and_ret;
|
goto free_and_ret;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
#ifdef WITH_SECCOMP
|
||||||
|
/* enforce strict syscall filter before parsing the document */
|
||||||
|
strictFilter();
|
||||||
|
#endif
|
||||||
|
|
||||||
/* open document if passed */
|
/* open document if passed */
|
||||||
if (file_idx != 0) {
|
if (file_idx != 0) {
|
||||||
if (page_number > 0) {
|
if (page_number > 0) {
|
||||||
|
|
Loading…
Reference in a new issue