Implemented conn.go and hanshake.go + unit tests

This commit is contained in:
robert
2026-01-04 20:24:15 +00:00
parent e98625ef58
commit 786533bbfc
4 changed files with 304 additions and 0 deletions

10
conn.go Normal file
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package ownwire_sdk
import (
"context"
)
type Conn interface {
WriteText(ctx context.Context, s string) error
ReadText(ctx context.Context) (string, error)
}

44
conn_inmem_test.go Normal file
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// This file defines an in-memory implementation of the Conn interface that is
// used ONLY by unit tests.
//
// The inmem_conn replaces a real WebSocket or network connection with simple
// Go channels. This allows handshake, sequencing, and message logic to be
// tested deterministically without spinning up a server, opening sockets,
// or relying on timing.
package ownwire_sdk
import (
"context"
)
type inmem_conn struct {
write_ch chan string
read_ch chan string
}
func new_inmem_conn() *inmem_conn {
return &inmem_conn{
write_ch: make(chan string, 16),
read_ch: make(chan string, 16),
}
}
func (c *inmem_conn) WriteText(ctx context.Context, s string) error {
select {
case c.write_ch <- s:
return nil
case <-ctx.Done():
return ctx.Err()
}
}
func (c *inmem_conn) ReadText(ctx context.Context) (string, error) {
select {
case s := <-c.read_ch:
return s, nil
case <-ctx.Done():
return "", ctx.Err()
}
}

118
handshake.go Normal file
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package ownwire_sdk
import (
"context"
"encoding/base64"
"fmt"
"time"
)
type SessionState struct {
SessionId string
ClientPubKeyB64 string
ServerPubKeyB64 string
SaltB64 string
SharedKey [32]byte
SessionIdBytes [16]byte
SeqOut uint64
SeqInMax uint64
}
type Handshaker struct {
Timeout time.Duration
GenClientKeyF func() (Keypair, error)
}
func (h Handshaker) EnsureDefaults() Handshaker {
if h.Timeout == 0 {
h.Timeout = 10 * time.Second
}
if h.GenClientKeyF == nil {
h.GenClientKeyF = GenClientKey
}
return h
}
func (h Handshaker) Run(ctx context.Context, conn Conn, resume_session_id string) (SessionState, []string, error) {
h = h.EnsureDefaults()
timeout_ctx, cancel := context.WithTimeout(ctx, h.Timeout)
defer cancel()
keypair, err := h.GenClientKeyF()
if err != nil {
return SessionState{}, nil, err
}
client_pub_b64 := base64.StdEncoding.EncodeToString(keypair.ClientPub)
if resume_session_id != "" {
open_cmd := fmt.Sprintf("/open:%s:%s", resume_session_id, client_pub_b64)
if err := conn.WriteText(timeout_ctx, open_cmd); err != nil {
return SessionState{}, nil, err
}
} else {
create_cmd := fmt.Sprintf("/create:%s", client_pub_b64)
if err := conn.WriteText(timeout_ctx, create_cmd); err != nil {
return SessionState{}, nil, err
}
}
pending := make([]string, 0, 8)
for {
line, err := conn.ReadText(timeout_ctx)
if err != nil {
return SessionState{}, nil, err
}
if len(line) >= 9 && line[:9] == "/session:" {
parsed, err := ParseSessionInit(line)
if err != nil {
return SessionState{}, nil, err
}
server_pub_raw, err := base64.StdEncoding.DecodeString(parsed.ServerPubKeyB64)
if err != nil {
return SessionState{}, nil, fmt.Errorf("invalid server pubkey base64: %w", err)
}
salt_raw, err := base64.StdEncoding.DecodeString(parsed.SaltB64)
if err != nil {
return SessionState{}, nil, fmt.Errorf("invalid salt base64: %w", err)
}
shared_key, err := DeriveSharedKey(parsed.SessionId, keypair.ClientPriv, server_pub_raw, salt_raw)
if err != nil {
return SessionState{}, nil, err
}
session_id_bytes, err := ParseUUIDBytes(parsed.SessionId)
if err != nil {
return SessionState{}, nil, err
}
out := SessionState{
SessionId: parsed.SessionId,
ClientPubKeyB64: client_pub_b64,
ServerPubKeyB64: parsed.ServerPubKeyB64,
SaltB64: parsed.SaltB64,
SharedKey: shared_key,
SessionIdBytes: session_id_bytes,
SeqOut: parsed.SeqInMax,
SeqInMax: parsed.SeqOut,
}
return out, pending, nil
}
pending = append(pending, line)
}
}

132
handshake_test.go Normal file
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package ownwire_sdk_test
import (
"context"
"crypto/ecdh"
"crypto/rand"
"encoding/base64"
. "github.com/onsi/ginkgo/v2"
. "github.com/onsi/gomega"
sdk "ownwire.net/ownwire-sdk"
)
var _ = Describe("Handshaker", func() {
It("sends /create when no resume session_id is provided and derives shared key", func() {
ctx := context.Background()
conn := sdk_test_new_inmem_conn()
client_kp, err := sdk.GenClientKey()
Expect(err).To(BeNil())
h := sdk.Handshaker{
GenClientKeyF: func() (sdk.Keypair, error) {
return client_kp, nil
},
}
curve := ecdh.P256()
server_priv, err := curve.GenerateKey(rand.Reader)
Expect(err).To(BeNil())
server_pub_raw := server_priv.PublicKey().Bytes()
server_pub_b64 := base64.StdEncoding.EncodeToString(server_pub_raw)
salt_raw := make([]byte, 32)
_, err = rand.Read(salt_raw)
Expect(err).To(BeNil())
salt_b64 := base64.StdEncoding.EncodeToString(salt_raw)
session_id := "cb653f53-6f7d-4aeb-ba0d-d2b17c290d8a"
go func() {
written := <-conn.write_ch
Expect(written).To(HavePrefix("/create:"))
conn.read_ch <- "/session:" + session_id + ":" + server_pub_b64 + ":" + salt_b64 + ":12:34"
}()
state, pending, err := h.Run(ctx, conn, "")
Expect(err).To(BeNil())
Expect(pending).To(BeEmpty())
Expect(state.SessionId).To(Equal(session_id))
Expect(state.ClientPubKeyB64).ToNot(BeEmpty())
want_key, err := sdk.DeriveSharedKey(session_id, client_kp.ClientPriv, server_pub_raw, salt_raw)
Expect(err).To(BeNil())
Expect(state.SharedKey).To(Equal(want_key))
Expect(state.SeqOut).To(Equal(uint64(34)))
Expect(state.SeqInMax).To(Equal(uint64(12)))
})
It("sends /open when resume session_id is provided", func() {
ctx := context.Background()
conn := sdk_test_new_inmem_conn()
client_kp, err := sdk.GenClientKey()
Expect(err).To(BeNil())
h := sdk.Handshaker{
GenClientKeyF: func() (sdk.Keypair, error) {
return client_kp, nil
},
}
curve := ecdh.P256()
server_priv, err := curve.GenerateKey(rand.Reader)
Expect(err).To(BeNil())
server_pub_raw := server_priv.PublicKey().Bytes()
server_pub_b64 := base64.StdEncoding.EncodeToString(server_pub_raw)
salt_raw := make([]byte, 32)
_, err = rand.Read(salt_raw)
Expect(err).To(BeNil())
salt_b64 := base64.StdEncoding.EncodeToString(salt_raw)
session_id := "cb653f53-6f7d-4aeb-ba0d-d2b17c290d8a"
go func() {
written := <-conn.write_ch
Expect(written).To(HavePrefix("/open:" + session_id + ":"))
conn.read_ch <- "/session:" + session_id + ":" + server_pub_b64 + ":" + salt_b64 + ":1:2"
}()
_, pending, err := h.Run(ctx, conn, session_id)
Expect(err).To(BeNil())
Expect(pending).To(BeEmpty())
})
})
func sdk_test_new_inmem_conn() *sdk_test_inmem_conn {
return &sdk_test_inmem_conn{
write_ch: make(chan string, 16),
read_ch: make(chan string, 16),
}
}
type sdk_test_inmem_conn struct {
write_ch chan string
read_ch chan string
}
func (c *sdk_test_inmem_conn) WriteText(ctx context.Context, s string) error {
select {
case c.write_ch <- s:
return nil
case <-ctx.Done():
return ctx.Err()
}
}
func (c *sdk_test_inmem_conn) ReadText(ctx context.Context) (string, error) {
select {
case s := <-c.read_ch:
return s, nil
case <-ctx.Done():
return "", ctx.Err()
}
}