package internal

import "github.com/cilium/ebpf/internal"

Index ¶

• Constants
• Variables
• func Align(n, alignment int) int
• func ErrorWithLog(err error, log []byte, logErr error) error
• func FeatureTest(name, version string, fn FeatureTestFn) func() error
• func Identifier(str string) string
• func NewBufferedSectionReader(ra io.ReaderAt, off, n int64) io.Reader
• func Pin(currentPath, newPath string, fd *sys.FD) error
• func PossibleCPUs() (int, error)
• func ReadAllCompressed(file string) ([]byte, error)
• func Unpin(pinnedPath string) error
• func WriteFormatted(src []byte, out io.Writer) error
• type DiscardZeroes
• func (DiscardZeroes) Write(p []byte) (int, error)
• type FeatureTestFn
• type SafeELFFile
• func NewSafeELFFile(r io.ReaderAt) (safe *SafeELFFile, err error)
• func (se *SafeELFFile) DynamicSymbols() (syms []elf.Symbol, err error)
• func (se *SafeELFFile) Symbols() (syms []elf.Symbol, err error)
• type UnsupportedFeatureError
• func (ufe *UnsupportedFeatureError) Error() string
• func (ufe *UnsupportedFeatureError) Is(target error) bool
• type VerifierError
• func (le *VerifierError) Error() string
• func (le *VerifierError) Unwrap() error
• type Version
• func KernelVersion() (Version, error)
• func NewVersion(ver string) (Version, error)
• func NewVersionFromCode(code uint32) Version
• func (v Version) Kernel() uint32
• func (v Version) Less(other Version) bool
• func (v Version) String() string
• func (v Version) Unspecified() bool

Constants ¶

const (
	// Version constant used in ELF binaries indicating that the loader needs to
	// substitute the eBPF program's version with the value of the kernel's
	// KERNEL_VERSION compile-time macro. Used for compatibility with BCC, gobpf
	// and RedSift.
	MagicKernelVersion = 0xFFFFFFFE
)

Variables ¶

var ClangEndian string

Clang is set to either "el" or "eb" depending on the host's endianness.

var ErrNotSupported = errors.New("not supported")

ErrNotSupported indicates that a feature is not supported by the current kernel.

var NativeEndian binary.ByteOrder

NativeEndian is set to either binary.BigEndian or binary.LittleEndian, depending on the host's endianness.

Functions ¶

func Align ¶

func Align(n, alignment int) int

Align returns 'n' updated to 'alignment' boundary.

func ErrorWithLog ¶

func ErrorWithLog(err error, log []byte, logErr error) error

ErrorWithLog returns an error that includes logs from the kernel verifier.

logErr should be the error returned by the syscall that generated the log. It is used to check for truncation of the output.

func FeatureTest ¶

func FeatureTest(name, version string, fn FeatureTestFn) func() error

FeatureTest wraps a function so that it is run at most once.

name should identify the tested feature, while version must be in the form Major.Minor[.Patch].

Returns an error wrapping ErrNotSupported if the feature is not supported.

func Identifier ¶

func Identifier(str string) string

Identifier turns a C style type or field name into an exportable Go equivalent.

func NewBufferedSectionReader ¶

func NewBufferedSectionReader(ra io.ReaderAt, off, n int64) io.Reader

NewBufferedSectionReader wraps an io.ReaderAt in an appropriately-sized buffered reader. It is a convenience function for reading subsections of ELF sections while minimizing the amount of read() syscalls made.

Syscall overhead is non-negligible in continuous integration context where ELFs might be accessed over virtual filesystems with poor random access performance. Buffering reads makes sense because (sub)sections end up being read completely anyway.

Use instead of the r.Seek() + io.LimitReader() pattern.

func Pin ¶

func Pin(currentPath, newPath string, fd *sys.FD) error

func PossibleCPUs ¶

func PossibleCPUs() (int, error)

PossibleCPUs returns the max number of CPUs a system may possibly have Logical CPU numbers must be of the form 0-n

func ReadAllCompressed ¶

func ReadAllCompressed(file string) ([]byte, error)

ReadAllCompressed decompresses a gzipped file into memory.

func Unpin ¶

func Unpin(pinnedPath string) error

func WriteFormatted ¶

func WriteFormatted(src []byte, out io.Writer) error

WriteFormatted outputs a formatted src into out.

If formatting fails it returns an informative error message.

Types ¶

type DiscardZeroes ¶

type DiscardZeroes struct{}

DiscardZeroes makes sure that all written bytes are zero before discarding them.

func (DiscardZeroes) Write ¶

func (DiscardZeroes) Write(p []byte) (int, error)

type FeatureTestFn ¶

type FeatureTestFn func() error

FeatureTestFn is used to determine whether the kernel supports a certain feature.

The return values have the following semantics:

err == ErrNotSupported: the feature is not available
err == nil: the feature is available
err != nil: the test couldn't be executed

type SafeELFFile ¶

type SafeELFFile struct {
	*elf.File
}

func NewSafeELFFile ¶

func NewSafeELFFile(r io.ReaderAt) (safe *SafeELFFile, err error)

NewSafeELFFile reads an ELF safely.

Any panic during parsing is turned into an error. This is necessary since there are a bunch of unfixed bugs in debug/elf.

https://github.com/golang/go/issues?q=is%3Aissue+is%3Aopen+debug%2Felf+in%3Atitle

func (*SafeELFFile) DynamicSymbols ¶

func (se *SafeELFFile) DynamicSymbols() (syms []elf.Symbol, err error)

DynamicSymbols is the safe version of elf.File.DynamicSymbols.

func (*SafeELFFile) Symbols ¶

func (se *SafeELFFile) Symbols() (syms []elf.Symbol, err error)

Symbols is the safe version of elf.File.Symbols.

type UnsupportedFeatureError ¶

type UnsupportedFeatureError struct {
	// The minimum Linux mainline version required for this feature.
	// Used for the error string, and for sanity checking during testing.
	MinimumVersion Version

	// The name of the feature that isn't supported.
	Name string
}

UnsupportedFeatureError is returned by FeatureTest() functions.

func (*UnsupportedFeatureError) Error ¶

func (ufe *UnsupportedFeatureError) Error() string

func (*UnsupportedFeatureError) Is ¶

func (ufe *UnsupportedFeatureError) Is(target error) bool

Is indicates that UnsupportedFeatureError is ErrNotSupported.

type VerifierError ¶

type VerifierError struct {
	// contains filtered or unexported fields
}

VerifierError includes information from the eBPF verifier.

func (*VerifierError) Error ¶

func (le *VerifierError) Error() string

func (*VerifierError) Unwrap ¶

func (le *VerifierError) Unwrap() error

type Version ¶

type Version [3]uint16

A Version in the form Major.Minor.Patch.

func KernelVersion ¶

func KernelVersion() (Version, error)

KernelVersion returns the version of the currently running kernel.

func NewVersion ¶

func NewVersion(ver string) (Version, error)

NewVersion creates a version from a string like "Major.Minor.Patch".

Patch is optional.

func NewVersionFromCode ¶

func NewVersionFromCode(code uint32) Version

NewVersionFromCode creates a version from a LINUX_VERSION_CODE.

func (Version) Kernel ¶

func (v Version) Kernel() uint32

Kernel implements the kernel's KERNEL_VERSION macro from linux/version.h. It represents the kernel version and patch level as a single value.

func (Version) Less ¶

func (v Version) Less(other Version) bool

Less returns true if the version is less than another version.

func (Version) String ¶

func (v Version) String() string

func (Version) Unspecified ¶

func (v Version) Unspecified() bool

Unspecified returns true if the version is all zero.

Source Files ¶

align.go cpu.go elf.go endian.go errors.go feature.go io.go output.go pinning.go vdso.go version.go

Directories ¶