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|
# Let's try testing with optional users that only have certain
# privileges. This will allow us to do more privilege/signing
# testing.
set test "server_privilege"
if {! [installtest_p]} { untested $test; return }
if {! [nss_p]} { untested "$test (no NSS)"; return }
# Note we have to be root.
set effective_uid [exec /usr/bin/id -u]
if {$effective_uid != 0} { untested "$test (must be root)"; return }
proc compile_with_privilege { test_name privilege script } {
global server_spec srcdir
set cmd [concat stap -p4 $privilege --use-server=$server_spec $script ]
send_log "executing: $cmd\n"
set failed 1
set module_name ''
eval spawn $cmd
expect {
-timeout 150
-re {^stap_[^ \t\r\n]*\.ko\r\n} {
set module_name [string trim "$expect_out(0,string)" \r\n]
set failed 0
exp_continue
}
-re {^.*\r\n} { exp_continue }
timeout {
kill -INT -[exp_pid] 2
}
}
catch {close}
set rc [wait -i $spawn_id]
set rc [lindex $rc 3]
set module_exists 0
set subtest "module compile"
if {$rc == 0 && $failed == 0 && [string length $module_name]} {
pass "$test_name ($subtest)"
# Make sure that the module and module signature were
# returned. The module signature isn't required for 'stapdev'
# privilege.
if { $privilege eq "--privilege=stapdev" } {
set subtest "module exists"
if {[file exists $module_name]} {
set module_exists 1
pass "$test_name ($subtest)"
} else {
fail "$test_name ($subtest)"
}
} else {
set subtest "module and signature exist"
set module_sig "${module_name}.sgn"
if {[file exists $module_name] && [file exists $module_sig] } {
set module_exists 1
pass "$test_name ($subtest)"
} else {
fail "$test_name ($subtest)"
}
}
} else {
fail "$test_name ($subtest)"
}
return [list $module_exists $module_name]
}
# If we don't have any of the optional users, we could just quit. But,
# we'll go on and make sure the module compilation works.
# Now start our own server.
if {! [setup_server]} {
untested "$test (server start failure)"
return
}
## We only want to change the system's trusted signer list in our mount
## namespace, not in the real system.
set subtest "adding trusted signer"
set cmd "stap --trust-servers=signer,no-prompt --use-server=$server_spec"
lassign [server_ns_as_root $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
# OK, now we've got a server. Use it to compile an unprivileged module
set subtest "unprivileged compile"
set full_test "$test - $subtest"
lassign [compile_with_privilege $full_test "--unprivileged" \
$srcdir/systemtap.server/hello.stp] module_exists module_name
# Make sure we can load the module. This will verify that the
# signature is correct and trusted.
if {$module_exists} {
set module_path [exec pwd]/$module_name
set unprivileged_module_path $module_path
# All the users should be able to load this module.
set subtest "stapusr unprivileged module run"
set cmd "staprun $module_path"
if {$systemtap_stapusr_user_exists} {
lassign [server_ns_as_user "stapusr" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapsys unprivileged module run"
if {$systemtap_stapsys_user_exists} {
lassign [server_ns_as_user "stapsys" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapdev unprivileged module run"
if {$systemtap_stapdev_user_exists} {
lassign [server_ns_as_user "stapdev" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
}
# Now compile a module using '--privilege=stapusr'. This should be the
# same thing as '--unprivileged'.
set subtest "stapusr privilege compile"
set full_test "$test - $subtest"
lassign [compile_with_privilege $full_test "--privilege=stapusr" \
$srcdir/systemtap.server/test.stp] module_exists module_name
# Make sure we can load the module. This will verify that the
# signature is correct and trusted.
if {$module_exists} {
set module_path [exec pwd]/$module_name
set stapusr_module_path $module_path
# All the users should be able to load this module.
set subtest "stapusr --privilege=stapusr module run"
set cmd "staprun $module_path"
if {$systemtap_stapusr_user_exists} {
lassign [server_ns_as_user "stapusr" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapsys --privilege=stapusr module run"
if {$systemtap_stapsys_user_exists} {
lassign [server_ns_as_user "stapsys" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapdev --privilege=stapusr module run"
if {$systemtap_stapdev_user_exists} {
lassign [server_ns_as_user "stapdev" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
}
# Now compile a module using '--privilege=stapsys'.
set subtest "stapsys privilege compile"
set full_test "$test - $subtest"
lassign [compile_with_privilege $full_test "--privilege=stapsys" \
$srcdir/systemtap.server/hello.stp ] module_exists module_name
# Make sure we can load the module. This will verify that the
# signature is correct and trusted.
if {$module_exists} {
set module_path [exec pwd]/$module_name
# Only the stapsys and stapdev users should be able to load this
# module.
set subtest "stapusr --privilege=stapsys module run"
set cmd "staprun $module_path"
if {$systemtap_stapusr_user_exists} {
lassign [server_ns_as_user "stapusr" $cmd] rc output
if {$rc == 0} {
fail "$test - $subtest"
} else {
pass "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapsys --privilege=stapsys module run"
if {$systemtap_stapsys_user_exists} {
lassign [server_ns_as_user "stapsys" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapdev --privilege=stapsys module run"
if {$systemtap_stapdev_user_exists} {
lassign [server_ns_as_user "stapdev" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
}
# Now compile a module using '--privilege=stapdev'. Note that
# 'stapdev' compiles don't need a module signature.
set subtest "stapdev privilege compile"
set full_test "$test - $subtest"
lassign [compile_with_privilege $full_test "--privilege=stapdev" \
$srcdir/systemtap.server/hello.stp ] module_exists module_name
# Make sure we can load the module.
if {$module_exists} {
set module_path [exec pwd]/$module_name
# Only the stapdev user should be able to load this module.
set subtest "stapusr --privilege=stapdev module run"
set cmd "staprun $module_path"
if {$systemtap_stapusr_user_exists} {
lassign [server_ns_as_user "stapusr" $cmd] rc output
if {$rc == 0} {
fail "$test - $subtest"
} else {
pass "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapsys --privilege=stapdev module run"
if {$systemtap_stapsys_user_exists} {
lassign [server_ns_as_user "stapsys" $cmd] rc output
if {$rc == 0} {
fail "$test - $subtest"
} else {
pass "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
set subtest "stapdev --privilege=stapdev module run"
if {$systemtap_stapdev_user_exists} {
lassign [server_ns_as_user "stapdev" $cmd] rc output
if {$rc == 0} {
pass "$test - $subtest"
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
}
# Let's try changing the module and signature file and make sure the
# verifcation fails. There isn't any point in trying this if we don't
# have the modules we need or the 'stapusr' or 'stapsys' optional
# users don't exist.
set subtest "module verification"
if {([info exists unprivileged_module_path]
&& [info exists stapusr_module_path])
&& ($systemtap_stapusr_user_exists || $systemtap_stapsys_user_exists)} {
# Use the shell to change the signature. This writes
# 0xdeadbeef at byte 10. (We could probably do this in tcl
# with 'binary format' and 'binary scan', but this was
# easier.
set rc 1
set unprivileged_module_sig_path "${unprivileged_module_path}.sgn"
if {$rc == 0} {
set cmd {printf '\\xdeadbeef' | dd of=${unprivileged_module_sig_path} bs=1 seek=10 conv=notrunc}
verbose -log "running: [subst $cmd]"
set rc 0
if {[catch {eval exec $cmd} output]} {
# non-zero exit status, get it:
if {[lindex $::errorCode 0] eq "CHILDSTATUS"} {
set rc [lindex $::errorCode 2]
}
}
if {$rc != 0} {
verbose -log "$output"
fail "$test - $subtest (file change)"
set rc 1
} else {
pass "$test - $subtest (file change)"
set rc 0
}
}
if {$systemtap_stapusr_user_exists} {
set user "stapusr"
} else {
set user "stapsys"
}
# Now that we've changed the signature, try to run the module (which
# should fail). Note that we only need to run the module once with
# either stapusr or stapsys.
if {$rc == 0} {
set subtest "loading module with change signature"
set cmd "staprun $unprivileged_module_path"
lassign [server_ns_as_user $user $cmd] rc output
# This *should* fail, since we munged the signature.
if {$rc == 0} {
fail "$test - $subtest"
} else {
pass "$test - $subtest"
}
}
# Now lets change the module and see if we can load it. However,
# changing the module is tricky. If for some reason the module
# verifcation succeeds, if we've changed some random bits in the
# module, we could cause the kernel to crash. So, instead, we'll
# use the signature file for the 'stapusr' module with the
# unprivileged module.
set stapusr_module_sig_path "${stapusr_module_path}.sgn"
set subtest "module rename"
verbose -log "renaming $stapusr_module_sig_path $unprivileged_module_sig_path"
if {! [catch {file rename -force $stapusr_module_sig_path \
$unprivileged_module_sig_path}]} {
pass "$test - $subtest"
set subtest "loading module with mismatched signature"
set cmd "staprun $unprivileged_module_path"
lassign [server_ns_as_user $user $cmd] rc output
# This *should* fail, since the module and signature don't match.
if {$rc == 0} {
fail "$test - $subtest"
} else {
pass "$test - $subtest"
}
} else {
fail "$test - $subtest"
}
} else {
untested "$test - $subtest"
}
shutdown_server
|
