util

package
v0.27.1 Latest Latest
Warning

This package is not in the latest version of its module.

 Go to latest Published: Nov 11, 2025 License: BSD-3-Clause Imports: 34 Imported by: 1

Documentation

Index

Constants

View Source 
const (
	RegisterMethodAuthKey = "authkey"
	RegisterMethodOIDC    = "oidc"
	RegisterMethodCLI     = "cli"
)
View Source 
const (
	ByteSize = 8

	// value related to RFC 1123 and 952.
	LabelHostnameLength = 63
)
View Source 
const (
	Base8              = 8
	Base10             = 10
	BitSize16          = 16
	BitSize32          = 32
	BitSize64          = 64
	PermissionFallback = 0o700
)

Variables

View Source 
var (
	ErrCannotDecryptResponse = errors.New("cannot decrypt response")
	ZstdCompression          = "zstd"
)
View Source 
var AddrPortComparer = cmp.Comparer(func(x, y netip.AddrPort) bool {
	return x == y
})
View Source 
var Comparers []cmp.Option = []cmp.Option{
	IPComparer, PrefixComparer, AddrPortComparer, MkeyComparer, NkeyComparer, DkeyComparer, ViewSliceIPProtoComparer,
}
View Source 
var DkeyComparer = cmp.Comparer(func(x, y key.DiscoPublic) bool {
	return x.String() == y.String()
})
View Source 
var ErrInvalidHostName = errors.New("invalid hostname")
View Source 
var IPComparer = cmp.Comparer(func(x, y netip.Addr) bool {
	return x.Compare(y) == 0
})
View Source 
var MkeyComparer = cmp.Comparer(func(x, y key.MachinePublic) bool {
	return x.String() == y.String()
})
View Source 
var NkeyComparer = cmp.Comparer(func(x, y key.NodePublic) bool {
	return x.String() == y.String()
})
View Source 
var PrefixComparer = cmp.Comparer(func(x, y netip.Prefix) bool {
	return x == y
})
View Source 
var TheInternet = sync.OnceValue(func() *netipx.IPSet {
	var internetBuilder netipx.IPSetBuilder
	internetBuilder.AddPrefix(netip.MustParsePrefix("2000::/3"))
	internetBuilder.AddPrefix(tsaddr.AllIPv4())

	internetBuilder.RemovePrefix(netip.MustParsePrefix("fc00::/7"))
	internetBuilder.RemovePrefix(netip.MustParsePrefix("10.0.0.0/8"))
	internetBuilder.RemovePrefix(netip.MustParsePrefix("172.16.0.0/12"))
	internetBuilder.RemovePrefix(netip.MustParsePrefix("192.168.0.0/16"))

	internetBuilder.RemovePrefix(tsaddr.TailscaleULARange())
	internetBuilder.RemovePrefix(tsaddr.CGNATRange())

	internetBuilder.RemovePrefix(netip.MustParsePrefix("fe80::/10"))
	internetBuilder.RemovePrefix(netip.MustParsePrefix("169.254.0.0/16"))

	theInternetSet, _ := internetBuilder.IPSet()

	return theInternetSet
})

TheInternet returns the IPSet for the Internet. https://www.youtube.com/watch?v=iDbyYGrswtg

View Source 
var ViewSliceIPProtoComparer = cmp.Comparer(func(a, b views.Slice[ipproto.Proto]) bool { return views.SliceEqual(a, b) })

Functions

func AbsolutePathFromConfigPath 

func AbsolutePathFromConfigPath(path string) string

func EnsureDir 

func EnsureDir(dir string) error

func EnsureHostname added in v0.27.0 

func EnsureHostname(hostinfo *tailcfg.Hostinfo, machineKey, nodeKey string) string

SafeHostname extracts a hostname from Hostinfo, providing sensible defaults if Hostinfo is nil or Hostname is empty. This prevents nil pointer dereferences and ensures nodes always have a valid hostname. The hostname is truncated to 63 characters to comply with DNS label length limits (RFC 1123). EnsureHostname guarantees a valid hostname for node registration. This function never fails - it always returns a valid hostname.

Strategy: 1. If hostinfo is nil/empty → generate default from keys 2. If hostname is provided → normalise it 3. If normalisation fails → generate invalid-<random> replacement

Returns the guaranteed-valid hostname to use.

func GenerateIPv4DNSRootDomain 

func GenerateIPv4DNSRootDomain(ipPrefix netip.Prefix) []dnsname.FQDN

From the netmask we can find out the wildcard bits (the bits that are not set in the netmask). This allows us to then calculate the subnets included in the subsequent class block and generate the entries.

func GenerateIPv6DNSRootDomain 

func GenerateIPv6DNSRootDomain(ipPrefix netip.Prefix) []dnsname.FQDN

From the netmask we can find out the wildcard bits (the bits that are not set in the netmask). This allows us to then calculate the subnets included in the subsequent class block and generate the entries.

func GenerateRandomBytes 

func GenerateRandomBytes(n int) ([]byte, error)

GenerateRandomBytes returns securely generated random bytes. It will return an error if the system's secure random number generator fails to function correctly, in which case the caller should not continue.

func GenerateRandomStringDNSSafe 

func GenerateRandomStringDNSSafe(size int) (string, error)

GenerateRandomStringDNSSafe returns a DNS-safe securely generated random string. It will return an error if the system's secure random number generator fails to function correctly, in which case the caller should not continue.

func GenerateRandomStringURLSafe 

func GenerateRandomStringURLSafe(n int) (string, error)

GenerateRandomStringURLSafe returns a URL-safe, base64 encoded securely generated random string. It will return an error if the system's secure random number generator fails to function correctly, in which case the caller should not continue.

func GetFileMode 

func GetFileMode(key string) fs.FileMode

func GetIPPrefixEndpoints 

func GetIPPrefixEndpoints(na netip.Prefix) (netip.Addr, netip.Addr)

func GrpcSocketDialer 

func GrpcSocketDialer(ctx context.Context, addr string) (net.Conn, error)

func IPSetAddrIter added in v0.26.0 

func IPSetAddrIter(ipSet *netipx.IPSet) iter.Seq[netip.Addr]

IPSetAddrIter returns a function that iterates over all the IPs in the IPSet.

func InvalidString added in v0.27.0 

func InvalidString() string

func IsCI added in v0.26.0 

func IsCI() bool

func LogErr 

func LogErr(err error, msg string)

func MustGenerateRandomStringDNSSafe added in v0.26.0 

func MustGenerateRandomStringDNSSafe(size int) string

func MustStringsToPrefixes added in v0.26.0 

func MustStringsToPrefixes(strings []string) []netip.Prefix

func NormaliseHostname added in v0.27.0 

func NormaliseHostname(name string) (string, error)

NormaliseHostname transforms a string into a valid DNS hostname. Returns error if the transformation results in an invalid hostname.

Transformations applied: - Converts to lowercase - Removes invalid DNS characters - Truncates to 63 characters if needed

After transformation, validates the result.

func ParseIPSet 

func ParseIPSet(arg string, bits *int) (*netipx.IPSet, error)

parseIPSet parses arg as one:

  • an IP address (IPv4 or IPv6)
  • the string "*" to match everything (both IPv4 & IPv6)
  • a CIDR (e.g. "192.168.0.0/16")
  • a range of two IPs, inclusive, separated by hyphen ("2eff::1-2eff::0800")

bits, if non-nil, is the legacy SrcBits CIDR length to make a IP address (without a slash) treated as a CIDR of *bits length. nolint

func ParseLoginURLFromCLILogin added in v0.25.1 

func ParseLoginURLFromCLILogin(output string) (*url.URL, error)

ParseLoginURLFromCLILogin parses the output of the tailscale up command to extract the login URL. It returns an error if not exactly one URL is found.

func PrefixesToString added in v0.26.0 

func PrefixesToString(prefixes []netip.Prefix) []string

func StringToIPPrefix 

func StringToIPPrefix(prefixes []string) ([]netip.Prefix, error)

func TSLogfWrapper 

func TSLogfWrapper() logger.Logf

func TailMapResponseToString 

func TailMapResponseToString(resp tailcfg.MapResponse) string

func TailNodesToString 

func TailNodesToString(nodes []*tailcfg.Node) string

func TailcfgFilterRulesToString added in v0.26.0 

func TailcfgFilterRulesToString(rules []tailcfg.FilterRule) string

func TailscaleVersionNewerOrEqual 

func TailscaleVersionNewerOrEqual(minimum, toCheck string) bool

func ValidateHostname added in v0.27.0 

func ValidateHostname(name string) error

ValidateHostname checks if a hostname meets DNS requirements. This function does NOT modify the input - it only validates. The hostname must already be lowercase and contain only valid characters.

func ValidateUsername added in v0.24.0 

func ValidateUsername(username string) error

ValidateUsername checks if a username is valid. It must be at least 2 characters long, start with a letter, and contain only letters, numbers, hyphens, dots, and underscores. It cannot contain more than one '@'. It cannot contain invalid characters.

func YesNo added in v0.27.0 

func YesNo(msg string) bool

YesNo takes a question and prompts the user to answer the question with a yes or no. It appends a y/n to the message. The question is written to stderr so that content can be redirected without interfering with the prompt.

Types

type DBLogWrapper 

type DBLogWrapper struct {
	Logger                *zerolog.Logger
	Level                 zerolog.Level
	Event                 *zerolog.Event
	SlowThreshold         time.Duration
	SkipErrRecordNotFound bool
	ParameterizedQueries  bool
}

func NewDBLogWrapper 

func NewDBLogWrapper(origin *zerolog.Logger, slowThreshold time.Duration, skipErrRecordNotFound bool, parameterizedQueries bool) *DBLogWrapper

func (*DBLogWrapper) Error 

func (l *DBLogWrapper) Error(ctx context.Context, msg string, data ...interface{})

func (*DBLogWrapper) Info 

func (l *DBLogWrapper) Info(ctx context.Context, msg string, data ...interface{})

func (*DBLogWrapper) LogMode 

func (l *DBLogWrapper) LogMode(gormLogger.LogLevel) gormLogger.Interface

func (*DBLogWrapper) ParamsFilter 

func (l *DBLogWrapper) ParamsFilter(ctx context.Context, sql string, params ...interface{}) (string, []interface{})

func (*DBLogWrapper) Trace 

func (l *DBLogWrapper) Trace(ctx context.Context, begin time.Time, fc func() (sql string, rowsAffected int64), err error)

func (*DBLogWrapper) Warn 

func (l *DBLogWrapper) Warn(ctx context.Context, msg string, data ...interface{})

type DBLogWrapperOption 

type DBLogWrapperOption func(*DBLogWrapper)

type Traceroute added in v0.26.0 

type Traceroute struct {
	// Hostname is the resolved hostname or IP address identifying the target
	Hostname string

	// IP is the IP address of the target
	IP netip.Addr

	// Route is the path taken to reach the target if successful. The list is ordered by the path taken.
	Route []TraceroutePath

	// Success indicates if the traceroute was successful.
	Success bool

	// Err contains an error if  the traceroute was not successful.
	Err error
}

func ParseTraceroute added in v0.26.0 

func ParseTraceroute(output string) (Traceroute, error)

ParseTraceroute parses the output of the traceroute command and returns a Traceroute struct.

type TraceroutePath added in v0.26.0 

type TraceroutePath struct {
	// Hop is the current jump in the total traceroute.
	Hop int

	// Hostname is the resolved hostname or IP address identifying the jump
	Hostname string

	// IP is the IP address of the jump
	IP netip.Addr

	// Latencies is a list of the latencies for this jump
	Latencies []time.Duration
}

Source Files

View all Source files

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL
go.dev uses cookies from Google to deliver and enhance the quality of its services and to analyze traffic. Learn more.