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bump libseccomp-golang v0.9.1

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full diff: 32f571b700...689e3c1541

Release notes:

* Version 0.9.1 - May 21, 2019
- Minimum supported version of libseccomp bumped to v2.2.0 (fc0298087f)
- PowerPC and S390(x) architectures are unavailable below library version v2.3.0 and will return errors if used with incompatible libraries
- Use Libseccomp's `seccomp_version` API to retrieve library version
- Unconditionally set TSync attribute for filters, due to Go's heavily threaded nature
- Fix [CVE-2017-18367](https://nvd.nist.gov/vuln/detail/CVE-2017-18367) - Multiple syscall arguments were incorrectly combined with logical-OR, instead of logical-AND (06e7a29f36)
- Fix a failure to build on Debian-based distributions due to CGo code
- Fix unit test failures on 32-bit architectures
- Improve several errors to be more verbose about their causes
- Add support for SCMP_ACT_LOG (with libseccomp versions 2.4.x and higher), permitting syscalls but logging their execution
- Add support for SCMP_FLTATR_CTL_LOG (with libseccomp versions 2.4.x and higher), logging not-allowed actions when they are denied

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This commit is contained in:
Sebastiaan van Stijn
2019-06-25 10:57:58 +02:00
parent 287582585f
commit bb41ef87f1
4 changed files with 299 additions and 131 deletions
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160
vendor/github.com/seccomp/libseccomp-golang/seccomp.go generated vendored
View File

@@ -27,6 +27,28 @@ import "C"
// Exported types
// VersionError denotes that the system libseccomp version is incompatible
// with this package.
type VersionError struct {
message string
minimum string
}
func (e VersionError) Error() string {
format := "Libseccomp version too low: "
if e.message != "" {
format += e.message + ": "
}
format += "minimum supported is "
if e.minimum != "" {
format += e.minimum + ": "
} else {
format += "2.2.0: "
}
format += "detected %d.%d.%d"
return fmt.Sprintf(format, verMajor, verMinor, verMicro)
}
// ScmpArch represents a CPU architecture. Seccomp can restrict syscalls on a
// per-architecture basis.
type ScmpArch uint
@@ -54,8 +76,8 @@ type ScmpSyscall int32
const (
// Valid architectures recognized by libseccomp
// ARM64 and all MIPS architectures are unsupported by versions of the
// library before v2.2 and will return errors if used
// PowerPC and S390(x) architectures are unavailable below library version
// v2.3.0 and will returns errors if used with incompatible libraries
// ArchInvalid is a placeholder to ensure uninitialized ScmpArch
// variables are invalid
@@ -115,6 +137,10 @@ const (
ActTrace ScmpAction = iota
// ActAllow permits the syscall to continue execution
ActAllow ScmpAction = iota
// ActLog permits the syscall to continue execution after logging it.
// This action is only usable when libseccomp API level 3 or higher is
// supported.
ActLog ScmpAction = iota
)
const (
@@ -151,6 +177,10 @@ const (
// GetArchFromString returns an ScmpArch constant from a string representing an
// architecture
func GetArchFromString(arch string) (ScmpArch, error) {
if err := ensureSupportedVersion(); err != nil {
return ArchInvalid, err
}
switch strings.ToLower(arch) {
case "x86":
return ArchX86, nil
@@ -185,7 +215,7 @@ func GetArchFromString(arch string) (ScmpArch, error) {
case "s390x":
return ArchS390X, nil
default:
return ArchInvalid, fmt.Errorf("cannot convert unrecognized string %s", arch)
return ArchInvalid, fmt.Errorf("cannot convert unrecognized string %q", arch)
}
}
@@ -229,7 +259,7 @@ func (a ScmpArch) String() string {
case ArchInvalid:
return "Invalid architecture"
default:
return "Unknown architecture"
return fmt.Sprintf("Unknown architecture %#x", uint(a))
}
}
@@ -253,7 +283,7 @@ func (a ScmpCompareOp) String() string {
case CompareInvalid:
return "Invalid comparison operator"
default:
return "Unrecognized comparison operator"
return fmt.Sprintf("Unrecognized comparison operator %#x", uint(a))
}
}
@@ -269,10 +299,12 @@ func (a ScmpAction) String() string {
case ActTrace:
return fmt.Sprintf("Action: Notify tracing processes with code %d",
(a >> 16))
case ActLog:
return "Action: Log system call"
case ActAllow:
return "Action: Allow system call"
default:
return "Unrecognized Action"
return fmt.Sprintf("Unrecognized Action %#x", uint(a))
}
}
@@ -298,10 +330,29 @@ func (a ScmpAction) GetReturnCode() int16 {
// GetLibraryVersion returns the version of the library the bindings are built
// against.
// The version is formatted as follows: Major.Minor.Micro
func GetLibraryVersion() (major, minor, micro int) {
func GetLibraryVersion() (major, minor, micro uint) {
return verMajor, verMinor, verMicro
}
// GetApi returns the API level supported by the system.
// Returns a positive int containing the API level, or 0 with an error if the
// API level could not be detected due to the library being older than v2.4.0.
// See the seccomp_api_get(3) man page for details on available API levels:
// https://github.com/seccomp/libseccomp/blob/master/doc/man/man3/seccomp_api_get.3
func GetApi() (uint, error) {
return getApi()
}
// SetApi forcibly sets the API level. General use of this function is strongly
// discouraged.
// Returns an error if the API level could not be set. An error is always
// returned if the library is older than v2.4.0
// See the seccomp_api_get(3) man page for details on available API levels:
// https://github.com/seccomp/libseccomp/blob/master/doc/man/man3/seccomp_api_get.3
func SetApi(api uint) error {
return setApi(api)
}
// Syscall functions
// GetName retrieves the name of a syscall from its number.
@@ -324,7 +375,7 @@ func (s ScmpSyscall) GetNameByArch(arch ScmpArch) (string, error) {
cString := C.seccomp_syscall_resolve_num_arch(arch.toNative(), C.int(s))
if cString == nil {
return "", fmt.Errorf("could not resolve syscall name")
return "", fmt.Errorf("could not resolve syscall name for %#x", int32(s))
}
defer C.free(unsafe.Pointer(cString))
@@ -338,12 +389,16 @@ func (s ScmpSyscall) GetNameByArch(arch ScmpArch) (string, error) {
// Returns the number of the syscall, or an error if no syscall with that name
// was found.
func GetSyscallFromName(name string) (ScmpSyscall, error) {
if err := ensureSupportedVersion(); err != nil {
return 0, err
}
cString := C.CString(name)
defer C.free(unsafe.Pointer(cString))
result := C.seccomp_syscall_resolve_name(cString)
if result == scmpError {
return 0, fmt.Errorf("could not resolve name to syscall")
return 0, fmt.Errorf("could not resolve name to syscall: %q", name)
}
return ScmpSyscall(result), nil
@@ -355,6 +410,9 @@ func GetSyscallFromName(name string) (ScmpSyscall, error) {
// Returns the number of the syscall, or an error if an invalid architecture is
// passed or a syscall with that name was not found.
func GetSyscallFromNameByArch(name string, arch ScmpArch) (ScmpSyscall, error) {
if err := ensureSupportedVersion(); err != nil {
return 0, err
}
if err := sanitizeArch(arch); err != nil {
return 0, err
}
@@ -364,7 +422,7 @@ func GetSyscallFromNameByArch(name string, arch ScmpArch) (ScmpSyscall, error) {
result := C.seccomp_syscall_resolve_name_arch(arch.toNative(), cString)
if result == scmpError {
return 0, fmt.Errorf("could not resolve name to syscall")
return 0, fmt.Errorf("could not resolve name to syscall: %q on %v", name, arch)
}
return ScmpSyscall(result), nil
@@ -386,12 +444,16 @@ func GetSyscallFromNameByArch(name string, arch ScmpArch) (ScmpSyscall, error) {
func MakeCondition(arg uint, comparison ScmpCompareOp, values ...uint64) (ScmpCondition, error) {
var condStruct ScmpCondition
if err := ensureSupportedVersion(); err != nil {
return condStruct, err
}
if comparison == CompareInvalid {
return condStruct, fmt.Errorf("invalid comparison operator")
} else if arg > 5 {
return condStruct, fmt.Errorf("syscalls only have up to 6 arguments")
return condStruct, fmt.Errorf("syscalls only have up to 6 arguments (%d given)", arg)
} else if len(values) > 2 {
return condStruct, fmt.Errorf("conditions can have at most 2 arguments")
return condStruct, fmt.Errorf("conditions can have at most 2 arguments (%d given)", len(values))
} else if len(values) == 0 {
return condStruct, fmt.Errorf("must provide at least one value to compare against")
}
@@ -413,6 +475,10 @@ func MakeCondition(arg uint, comparison ScmpCompareOp, values ...uint64) (ScmpCo
// GetNativeArch returns architecture token representing the native kernel
// architecture
func GetNativeArch() (ScmpArch, error) {
if err := ensureSupportedVersion(); err != nil {
return ArchInvalid, err
}
arch := C.seccomp_arch_native()
return archFromNative(arch)
@@ -435,6 +501,10 @@ type ScmpFilter struct {
// Returns a reference to a valid filter context, or nil and an error if the
// filter context could not be created or an invalid default action was given.
func NewFilter(defaultAction ScmpAction) (*ScmpFilter, error) {
if err := ensureSupportedVersion(); err != nil {
return nil, err
}
if err := sanitizeAction(defaultAction); err != nil {
return nil, err
}
@@ -449,6 +519,13 @@ func NewFilter(defaultAction ScmpAction) (*ScmpFilter, error) {
filter.valid = true
runtime.SetFinalizer(filter, filterFinalizer)
// Enable TSync so all goroutines will receive the same rules
// If the kernel does not support TSYNC, allow us to continue without error
if err := filter.setFilterAttr(filterAttrTsync, 0x1); err != nil && err != syscall.ENOTSUP {
filter.Release()
return nil, fmt.Errorf("could not create filter - error setting tsync bit: %v", err)
}
return filter, nil
}
@@ -505,7 +582,7 @@ func (f *ScmpFilter) Release() {
// The source filter src will be released as part of the process, and will no
// longer be usable or valid after this call.
// To be merged, filters must NOT share any architectures, and all their
// attributes (Default Action, Bad Arch Action, No New Privs and TSync bools)
// attributes (Default Action, Bad Arch Action, and No New Privs bools)
// must match.
// The filter src will be merged into the filter this is called on.
// The architectures of the src filter not present in the destination, and all
@@ -678,24 +755,24 @@ func (f *ScmpFilter) GetNoNewPrivsBit() (bool, error) {
return true, nil
}
// GetTsyncBit returns whether Thread Synchronization will be enabled on the
// filter being loaded, or an error if an issue was encountered retrieving the
// value.
// Thread Sync ensures that all members of the thread group of the calling
// process will share the same Seccomp filter set.
// Tsync is a fairly recent addition to the Linux kernel and older kernels
// lack support. If the running kernel does not support Tsync and it is
// requested in a filter, Libseccomp will not enable TSync support and will
// proceed as normal.
// This function is unavailable before v2.2 of libseccomp and will return an
// error.
func (f *ScmpFilter) GetTsyncBit() (bool, error) {
tSync, err := f.getFilterAttr(filterAttrTsync)
// GetLogBit returns the current state the Log bit will be set to on the filter
// being loaded, or an error if an issue was encountered retrieving the value.
// The Log bit tells the kernel that all actions taken by the filter, with the
// exception of ActAllow, should be logged.
// The Log bit is only usable when libseccomp API level 3 or higher is
// supported.
func (f *ScmpFilter) GetLogBit() (bool, error) {
log, err := f.getFilterAttr(filterAttrLog)
if err != nil {
api, apiErr := getApi()
if (apiErr != nil && api == 0) || (apiErr == nil && api < 3) {
return false, fmt.Errorf("getting the log bit is only supported in libseccomp 2.4.0 and newer with API level 3 or higher")
}
return false, err
}
if tSync == 0 {
if log == 0 {
return false, nil
}
@@ -728,25 +805,26 @@ func (f *ScmpFilter) SetNoNewPrivsBit(state bool) error {
return f.setFilterAttr(filterAttrNNP, toSet)
}
// SetTsync sets whether Thread Synchronization will be enabled on the filter
// being loaded. Returns an error if setting Tsync failed, or the filter is
// invalid.
// Thread Sync ensures that all members of the thread group of the calling
// process will share the same Seccomp filter set.
// Tsync is a fairly recent addition to the Linux kernel and older kernels
// lack support. If the running kernel does not support Tsync and it is
// requested in a filter, Libseccomp will not enable TSync support and will
// proceed as normal.
// This function is unavailable before v2.2 of libseccomp and will return an
// error.
func (f *ScmpFilter) SetTsync(enable bool) error {
// SetLogBit sets the state of the Log bit, which will be applied on filter
// load, or an error if an issue was encountered setting the value.
// The Log bit is only usable when libseccomp API level 3 or higher is
// supported.
func (f *ScmpFilter) SetLogBit(state bool) error {
var toSet C.uint32_t = 0x0
if enable {
if state {
toSet = 0x1
}
return f.setFilterAttr(filterAttrTsync, toSet)
err := f.setFilterAttr(filterAttrLog, toSet)
if err != nil {
api, apiErr := getApi()
if (apiErr != nil && api == 0) || (apiErr == nil && api < 3) {
return fmt.Errorf("setting the log bit is only supported in libseccomp 2.4.0 and newer with API level 3 or higher")
}
}
return err
}
// SetSyscallPriority sets a syscall's priority.