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smsg

package

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Versions in this module

v0

v0.2.0

Feb 3, 2026

Changes in this version

+ const ABRSafetyFactor

+ const ABRVersion

+ const DefaultChunkSize

+ const FormatV3

+ const KeyMethodDirect

+ const KeyMethodLTHNRolling

+ var ABRPresets = []struct{ ... }

+ var ErrLicenseRequired = errors.New("license is required for stream decryption")

+ var ErrNoValidKey = errors.New("no valid wrapped key found for current date")

+ var ErrStreamKeyExpired = errors.New("stream key expired (outside rolling window)")

+ func DecryptV3(data []byte, params *StreamParams) (*Message, *Header, error)

+ func DecryptV3Chunk(payload []byte, cek []byte, chunkIndex int, chunked *ChunkedInfo) ([]byte, error)

+ func DeriveStreamKey(date, license, fingerprint string) []byte

+ func EncryptV3(msg *Message, params *StreamParams, manifest *Manifest) ([]byte, error)

+ func GenerateCEK() ([]byte, error)

+ func GetCadenceWindowDuration(cadence Cadence) time.Duration

+ func GetRollingDates() (current, next string)

+ func GetRollingDatesAt(t time.Time) (current, next string)

+ func GetRollingPeriods(cadence Cadence, t time.Time) (current, next string)

+ func GetV3Payload(data []byte) ([]byte, error)

+ func UnwrapCEK(wrappedB64 string, streamKey []byte) ([]byte, error)

+ func UnwrapCEKFromHeader(header *Header, params *StreamParams) ([]byte, error)

+ func WrapCEK(cek, streamKey []byte) (string, error)

+ func WriteABRManifest(manifest *ABRManifest, path string) error

+ type ABRBandwidthEstimator struct

+ func NewABRBandwidthEstimator(maxSamples int) *ABRBandwidthEstimator

+ func (e *ABRBandwidthEstimator) Estimate() int

+ func (e *ABRBandwidthEstimator) RecordSample(bytes int, durationMs int)

+ type ABRManifest struct

+ DefaultIdx int

+ Duration int

+ Password string

+ Title string

+ Variants []Variant

+ Version string

+ func NewABRManifest(title string) *ABRManifest

+ func ParseABRManifest(data []byte) (*ABRManifest, error)

+ func ReadABRManifest(path string) (*ABRManifest, error)

+ func (m *ABRManifest) AddVariant(v Variant)

+ func (m *ABRManifest) GetVariant(idx int) *Variant

+ func (m *ABRManifest) SelectVariant(bandwidthBPS int) int

+ type Cadence string

+ const CadenceDaily

+ const CadenceHalfDay

+ const CadenceHourly

+ const CadenceQuarter

+ type ChunkInfo struct

+ Offset int

+ Size int

+ type ChunkedInfo struct

+ ChunkSize int

+ Index []ChunkInfo

+ TotalChunks int

+ TotalSize int64

type Header

+ Cadence Cadence

+ Chunked *ChunkedInfo

+ KeyMethod string

+ WrappedKeys []WrappedKey

+ func GetV3Header(data []byte) (*Header, error)

+ func GetV3HeaderFromPrefix(data []byte) (*Header, int, error)

+ type StreamParams struct

+ Cadence Cadence

+ ChunkSize int

+ Fingerprint string

+ License string

+ type Variant struct

+ Bandwidth int

+ ChunkCount int

+ Codecs string

+ FileSize int64

+ Height int

+ Name string

+ URL string

+ Width int

+ func VariantFromSMSG(name string, bandwidth, width, height int, smsgPath string) (*Variant, error)

+ type WrappedKey struct

+ Date string

+ Wrapped string

v0.1.0

Jan 10, 2026

Changes in this version

+ const CompressionGzip

+ const CompressionNone

+ const CompressionZstd

+ const FormatV1

+ const FormatV2

+ func EncryptV2(msg *Message, password string) ([]byte, error)

+ func EncryptV2WithManifest(msg *Message, password string, manifest *Manifest) ([]byte, error)

+ func EncryptV2WithOptions(msg *Message, password string, manifest *Manifest, compression string) ([]byte, error)

+ func EncryptWithManifest(msg *Message, password string, manifest *Manifest) ([]byte, error)

+ func EncryptWithManifestBase64(msg *Message, password string, manifest *Manifest) (string, error)

type Header

+ Compression string

+ Format string

+ Manifest *Manifest

+ type Manifest struct

+ Album string

+ Artist string

+ Duration int

+ ExpiresAt int64

+ Extra map[string]string

+ Format string

+ Genre string

+ IssuedAt int64

+ LicenseType string

+ Links map[string]string

+ ReleaseType string

+ Tags []string

+ Title string

+ Tracks []Track

+ Year int

+ func NewManifest(title string) *Manifest

+ func (m *Manifest) AddLink(platform, url string) *Manifest

+ func (m *Manifest) AddTrack(title string, start float64) *Manifest

+ func (m *Manifest) AddTrackFull(title string, start, end float64, trackType string) *Manifest

+ func (m *Manifest) IsExpired() bool

+ func (m *Manifest) TimeRemaining() int64

+ func (m *Manifest) WithExpiration(expiresAt int64) *Manifest

+ func (m *Manifest) WithPreviewAccess(seconds int) *Manifest

+ func (m *Manifest) WithRentalDuration(durationSeconds int64) *Manifest

+ func (m *Manifest) WithStreamingAccess(hours int) *Manifest

type Message

+ func (m *Message) AddBinaryAttachment(name string, data []byte, mimeType string) *Message

+ type Track struct

+ End float64

+ Start float64

+ Title string

+ TrackNum int

+ Type string

v0.0.2

Dec 27, 2025

Changes in this version

+ const Magic

+ const Version

+ var ErrDecryptionFailed = errors.New("decryption failed (wrong password?)")

+ var ErrEmptyMessage = errors.New("message cannot be empty")

+ var ErrInvalidMagic = errors.New("invalid SMSG magic")

+ var ErrInvalidPayload = errors.New("invalid SMSG payload")

+ var ErrPasswordRequired = errors.New("password is required")

+ func DeriveKey(password string) []byte

+ func Encrypt(msg *Message, password string) ([]byte, error)

+ func EncryptBase64(msg *Message, password string) (string, error)

+ func EncryptWithHint(msg *Message, password, hint string) ([]byte, error)

+ func QuickDecrypt(encoded, password string) (string, error)

+ func QuickEncrypt(body, password string) (string, error)

+ func Validate(data []byte) error

+ type Attachment struct

+ Content string

+ MimeType string

+ Name string

+ Size int

+ type Header struct

+ Algorithm string

+ Hint string

+ Version string

+ func GetInfo(data []byte) (*Header, error)

+ func GetInfoBase64(encoded string) (*Header, error)

+ type Message struct

+ Attachments []Attachment

+ Body string

+ From string

+ Meta map[string]string

+ ReplyKey *PKIInfo

+ Subject string

+ Timestamp int64

+ func Decrypt(data []byte, password string) (*Message, error)

+ func DecryptBase64(encoded, password string) (*Message, error)

+ func NewMessage(body string) *Message

+ func (m *Message) AddAttachment(name, content, mimeType string) *Message

+ func (m *Message) GetAttachment(name string) *Attachment

+ func (m *Message) SetMeta(key, value string) *Message

+ func (m *Message) WithFrom(from string) *Message

+ func (m *Message) WithReplyKey(publicKeyB64 string) *Message

+ func (m *Message) WithReplyKeyInfo(pki *PKIInfo) *Message

+ func (m *Message) WithSubject(subject string) *Message

+ func (m *Message) WithTimestamp(ts int64) *Message

+ type PKIInfo struct

+ Algorithm string

+ Fingerprint string

+ KeyID string

+ PublicKey string