[#53] session: move package from neofs-api-go

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>

session/session.go

@@ -0,0 +1,282 @@
+package session
+
+import (
+	"crypto/ecdsa"
+
+	"github.com/nspcc-dev/neofs-api-go/v2/refs"
+	"github.com/nspcc-dev/neofs-api-go/v2/session"
+	v2signature "github.com/nspcc-dev/neofs-api-go/v2/signature"
+	"github.com/nspcc-dev/neofs-sdk-go/owner"
+	"github.com/nspcc-dev/neofs-sdk-go/signature"
+	sigutil "github.com/nspcc-dev/neofs-sdk-go/util/signature"
+)
+
+// Token represents NeoFS API v2-compatible
+// session token.
+type Token session.SessionToken
+
+// NewTokenFromV2 wraps session.SessionToken message structure
+// into Token.
+//
+// Nil session.SessionToken converts to nil.
+func NewTokenFromV2(tV2 *session.SessionToken) *Token {
+	return (*Token)(tV2)
+}
+
+// NewToken creates and returns blank Token.
+//
+// Defaults:
+//  - body: nil;
+//  - id: nil;
+//  - ownerId: nil;
+//  - sessionKey: nil;
+//  - exp: 0;
+//  - iat: 0;
+//  - nbf: 0;
+func NewToken() *Token {
+	return NewTokenFromV2(new(session.SessionToken))
+}
+
+// ToV2 converts Token to session.SessionToken message structure.
+//
+// Nil Token converts to nil.
+func (t *Token) ToV2() *session.SessionToken {
+	return (*session.SessionToken)(t)
+}
+
+func (t *Token) setBodyField(setter func(*session.SessionTokenBody)) {
+	token := (*session.SessionToken)(t)
+	body := token.GetBody()
+
+	if body == nil {
+		body = new(session.SessionTokenBody)
+		token.SetBody(body)
+	}
+
+	setter(body)
+}
+
+// ID returns Token identifier.
+func (t *Token) ID() []byte {
+	return (*session.SessionToken)(t).
+		GetBody().
+		GetID()
+}
+
+// SetID sets Token identifier.
+func (t *Token) SetID(v []byte) {
+	t.setBodyField(func(body *session.SessionTokenBody) {
+		body.SetID(v)
+	})
+}
+
+// OwnerID returns Token's owner identifier.
+func (t *Token) OwnerID() *owner.ID {
+	return owner.NewIDFromV2(
+		(*session.SessionToken)(t).
+			GetBody().
+			GetOwnerID(),
+	)
+}
+
+// SetOwnerID sets Token's owner identifier.
+func (t *Token) SetOwnerID(v *owner.ID) {
+	t.setBodyField(func(body *session.SessionTokenBody) {
+		body.SetOwnerID(v.ToV2())
+	})
+}
+
+// SessionKey returns public key of the session
+// in a binary format.
+func (t *Token) SessionKey() []byte {
+	return (*session.SessionToken)(t).
+		GetBody().
+		GetSessionKey()
+}
+
+// SetSessionKey sets public key of the session
+// in a binary format.
+func (t *Token) SetSessionKey(v []byte) {
+	t.setBodyField(func(body *session.SessionTokenBody) {
+		body.SetSessionKey(v)
+	})
+}
+
+func (t *Token) setLifetimeField(f func(*session.TokenLifetime)) {
+	t.setBodyField(func(body *session.SessionTokenBody) {
+		lt := body.GetLifetime()
+		if lt == nil {
+			lt = new(session.TokenLifetime)
+			body.SetLifetime(lt)
+		}
+
+		f(lt)
+	})
+}
+
+// Exp returns epoch number of the token expiration.
+func (t *Token) Exp() uint64 {
+	return (*session.SessionToken)(t).
+		GetBody().
+		GetLifetime().
+		GetExp()
+}
+
+// SetExp sets epoch number of the token expiration.
+func (t *Token) SetExp(exp uint64) {
+	t.setLifetimeField(func(lt *session.TokenLifetime) {
+		lt.SetExp(exp)
+	})
+}
+
+// Nbf returns starting epoch number of the token.
+func (t *Token) Nbf() uint64 {
+	return (*session.SessionToken)(t).
+		GetBody().
+		GetLifetime().
+		GetNbf()
+}
+
+// SetNbf sets starting epoch number of the token.
+func (t *Token) SetNbf(nbf uint64) {
+	t.setLifetimeField(func(lt *session.TokenLifetime) {
+		lt.SetNbf(nbf)
+	})
+}
+
+// Iat returns starting epoch number of the token.
+func (t *Token) Iat() uint64 {
+	return (*session.SessionToken)(t).
+		GetBody().
+		GetLifetime().
+		GetIat()
+}
+
+// SetIat sets the number of the epoch in which the token was issued.
+func (t *Token) SetIat(iat uint64) {
+	t.setLifetimeField(func(lt *session.TokenLifetime) {
+		lt.SetIat(iat)
+	})
+}
+
+// Sign calculates and writes signature of the Token data.
+//
+// Returns signature calculation errors.
+func (t *Token) Sign(key *ecdsa.PrivateKey) error {
+	tV2 := (*session.SessionToken)(t)
+
+	signedData := v2signature.StableMarshalerWrapper{
+		SM: tV2.GetBody(),
+	}
+
+	return sigutil.SignDataWithHandler(key, signedData, func(key, sig []byte) {
+		tSig := tV2.GetSignature()
+		if tSig == nil {
+			tSig = new(refs.Signature)
+		}
+
+		tSig.SetKey(key)
+		tSig.SetSign(sig)
+
+		tV2.SetSignature(tSig)
+	})
+}
+
+// VerifySignature checks if token signature is
+// presented and valid.
+func (t *Token) VerifySignature() bool {
+	tV2 := (*session.SessionToken)(t)
+
+	signedData := v2signature.StableMarshalerWrapper{
+		SM: tV2.GetBody(),
+	}
+
+	return sigutil.VerifyDataWithSource(signedData, func() (key, sig []byte) {
+		tSig := tV2.GetSignature()
+		return tSig.GetKey(), tSig.GetSign()
+	}) == nil
+}
+
+// Signature returns Token signature.
+func (t *Token) Signature() *signature.Signature {
+	return signature.NewFromV2(
+		(*session.SessionToken)(t).
+			GetSignature(),
+	)
+}
+
+// SetContext sets context of the Token.
+//
+// Supported contexts:
+//  - *ContainerContext.
+//
+// Resets context if it is not supported.
+func (t *Token) SetContext(v interface{}) {
+	var cV2 session.SessionTokenContext
+
+	switch c := v.(type) {
+	case *ContainerContext:
+		cV2 = c.ToV2()
+	}
+
+	t.setBodyField(func(body *session.SessionTokenBody) {
+		body.SetContext(cV2)
+	})
+}
+
+// Context returns context of the Token.
+//
+// Supports same contexts as SetContext.
+//
+// Returns nil if context is not supported.
+func (t *Token) Context() interface{} {
+	switch v := (*session.SessionToken)(t).
+		GetBody().
+		GetContext(); c := v.(type) {
+	default:
+		return nil
+	case *session.ContainerSessionContext:
+		return ContainerContextFromV2(c)
+	}
+}
+
+// GetContainerContext is a helper function that casts
+// Token context to ContainerContext.
+//
+// Returns nil if context is not a ContainerContext.
+func GetContainerContext(t *Token) *ContainerContext {
+	c, _ := t.Context().(*ContainerContext)
+	return c
+}
+
+// Marshal marshals Token into a protobuf binary form.
+//
+// Buffer is allocated when the argument is empty.
+// Otherwise, the first buffer is used.
+func (t *Token) Marshal(bs ...[]byte) ([]byte, error) {
+	var buf []byte
+	if len(bs) > 0 {
+		buf = bs[0]
+	}
+
+	return (*session.SessionToken)(t).
+		StableMarshal(buf)
+}
+
+// Unmarshal unmarshals protobuf binary representation of Token.
+func (t *Token) Unmarshal(data []byte) error {
+	return (*session.SessionToken)(t).
+		Unmarshal(data)
+}
+
+// MarshalJSON encodes Token to protobuf JSON format.
+func (t *Token) MarshalJSON() ([]byte, error) {
+	return (*session.SessionToken)(t).
+		MarshalJSON()
+}
+
+// UnmarshalJSON decodes Token from protobuf JSON format.
+func (t *Token) UnmarshalJSON(data []byte) error {
+	return (*session.SessionToken)(t).
+		UnmarshalJSON(data)
+}