store messages sent through ICBM

0x01_generic_service_controls.go

@@ -6,7 +6,6 @@ import (
 	"aim-oscar/util"
 	"context"
 	"encoding/binary"
-	"fmt"
 	"time"
 
 	"github.com/pkg/errors"
@@ -73,9 +72,8 @@ func (g *GenericServiceControls) HandleSNAC(ctx context.Context, db *bun.DB, sna
 		}
 
 		onlineSnac := oscar.NewSNAC(1, 0xf)
-		uin := fmt.Sprint(user.UIN)
-		onlineSnac.Data.WriteUint8(uint8(len(uin)))
-		onlineSnac.Data.WriteString(uin)
+		onlineSnac.Data.WriteUint8(uint8(len(user.Username)))
+		onlineSnac.Data.WriteString(user.Username)
 		onlineSnac.Data.WriteUint16(0) // warning level
 
 		user.Status = "active"

0x04_ICBM.go

@@ -1,10 +1,12 @@
 package main
 
 import (
+	"aim-oscar/models"
 	"aim-oscar/oscar"
 	"bytes"
 	"context"
 	"encoding/binary"
+	"log"
 
 	"github.com/pkg/errors"
 	"github.com/uptrace/bun"
@@ -85,6 +87,109 @@ func (icbm *ICBM) HandleSNAC(ctx context.Context, db *bun.DB, snac *oscar.SNAC)
 		channelFlap.Data.WriteBinary(channelSnac)
 		session.Send(channelFlap)
 
+		return ctx, nil
+
+	// Client wants to send a message to someone through the server
+	case 0x06:
+		user := models.UserFromContext(ctx)
+		if user == nil {
+			return ctx, errors.New("context should have User")
+		}
+
+		msgID, _ := snac.Data.ReadUint64()
+		msgChannel, _ := snac.Data.ReadUint16()
+		to, _ := snac.Data.ReadLPString()
+
+		if msgChannel != 1 {
+			log.Printf("Message for unsupported channel %d", msgChannel)
+			return ctx, nil
+		}
+
+		tlvs, err := oscar.UnmarshalTLVs(snac.Data.Bytes())
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not unmarshal message tlvs")
+		}
+
+		messageTLV := oscar.FindTLV(tlvs, 0x2)
+		if messageTLV == nil {
+			return ctx, errors.New("missing messageTLV 0x2")
+		}
+
+		// Parse fragment (array of required capabilities, yawn)
+		messageTLVData := oscar.Buffer{}
+		messageTLVData.Write(messageTLV.Data)
+
+		fragmentNum, err := messageTLVData.ReadUint8()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read fragment identifier")
+		} else if fragmentNum != 5 {
+			return ctx, errors.New("expected first fragment identifier to be 5")
+		}
+
+		fragmentVersion, err := messageTLVData.ReadUint8()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read fragment version")
+		} else if fragmentVersion != 1 {
+			return ctx, errors.New("expected first fragment version to be 1")
+		}
+
+		fragmentLength, err := messageTLVData.ReadUint16()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read fragment data length")
+		}
+
+		// Skip over all the capabilities
+		messageTLVData.Seek(int(fragmentLength))
+
+		// This should be the start of the message contents fragment
+		fragmentNum, err = messageTLVData.ReadUint8()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read fragment identifier")
+		} else if fragmentNum != 1 {
+			return ctx, errors.New("expected second fragment identifier to be 1")
+		}
+
+		fragmentVersion, err = messageTLVData.ReadUint8()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read fragment version")
+		} else if fragmentVersion != 1 {
+			return ctx, errors.New("expected second fragment version to be 1")
+		}
+
+		fragmentLength, err = messageTLVData.ReadUint16()
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read second fragment data length")
+		}
+
+		// Skip over the charset + language
+		messageTLVData.Seek(4)
+
+		messageContents := make([]byte, fragmentLength-4)
+		n, err := messageTLVData.Read(messageContents)
+		if err != nil {
+			return ctx, errors.Wrap(err, "could not read message contents from fragment")
+		}
+		if n < int(fragmentLength)-4 {
+			return ctx, errors.New("read insufficient data from message fragment")
+		}
+
+		if err = models.InsertMessage(ctx, db, msgID, user.Username, to, string(messageContents)); err != nil {
+			return ctx, errors.Wrap(err, "could not insert message")
+		}
+
+		// The Client usually wants a response that the server got the message. It checks that the message
+		// back has the same message ID that was sent and the user it was sent to.
+		ackTLV := oscar.FindTLV(tlvs, 3)
+		if ackTLV != nil {
+			ackSnac := oscar.NewSNAC(4, 0xc)
+			ackSnac.Data.WriteUint64(msgID)
+			ackSnac.Data.WriteUint16(2)
+			ackSnac.Data.WriteLPString(user.Username)
+			ackFlap := oscar.NewFLAP(2)
+			ackFlap.Data.WriteBinary(ackSnac)
+			return ctx, session.Send(ackFlap)
+		}
+
 		return ctx, nil
 	}
 

0x17_authorization_registration_service.go

@@ -22,7 +22,7 @@ const CIPHER_LENGTH = 64
 const AIM_MD5_STRING = "AOL Instant Messenger (SM)"
 
 type AuthorizationCookie struct {
-	UIN int
+	UIN int64
 	X   string
 }
 

main.go

@@ -53,7 +53,7 @@ func main() {
 	db.AddQueryHook(bundebug.NewQueryHook(bundebug.WithVerbose(true)))
 
 	// Register our DB models
-	db.RegisterModel((*models.User)(nil))
+	db.RegisterModel((*models.User)(nil), (*models.Message)(nil))
 
 	// dev: load in fixtures to test against
 	fixture := dbfixture.New(db, dbfixture.WithRecreateTables())

models/Message.go

@@ -0,0 +1,33 @@
+package models
+
+import (
+	"context"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/uptrace/bun"
+)
+
+type Message struct {
+	bun.BaseModel `bun:"table:messages"`
+	MessageID     uint64 `bun:",pk,notnull,unique"`
+	From          string
+	To            string
+	Contents      string
+	CreatedAt     time.Time `bun:",nullzero,notnull,default:current_timestamp"`
+	DeliveredAt   time.Time `bun:",nullzero"`
+}
+
+func InsertMessage(ctx context.Context, db *bun.DB, messageId uint64, from string, to string, contents string) error {
+	msg := &Message{
+		MessageID: messageId,
+		From:      from,
+		To:        to,
+		Contents:  contents,
+	}
+	if _, err := db.NewInsert().Model(msg).Exec(ctx); err != nil {
+		return errors.Wrap(err, "could not update user")
+	}
+
+	return nil
+}

models/User.go

@@ -11,7 +11,7 @@ import (
 
 type User struct {
 	bun.BaseModel  `bun:"table:users"`
-	UIN            int    `bun:",pk,autoincrement"`
+	UIN            int64  `bun:",pk,autoincrement"`
 	Email          string `bun:",unique"`
 	Username       string `bun:",unique"`
 	Password       string
@@ -43,7 +43,7 @@ func UserByUsername(ctx context.Context, db *bun.DB, username string) (*User, er
 	return user, nil
 }
 
-func UserByUIN(ctx context.Context, db *bun.DB, uin int) (*User, error) {
+func UserByUIN(ctx context.Context, db *bun.DB, uin int64) (*User, error) {
 	user := new(User)
 	if err := db.NewSelect().Model(user).Where("uin = ?", uin).Scan(ctx, user); err != nil {
 		if err == sql.ErrNoRows {

models/fixtures.yml

@@ -3,3 +3,5 @@
     - username: toof
       password: bar
       email: toof@plot.club
+- model: Message
+  rows: []

oscar/buf.go

@@ -4,12 +4,86 @@ import (
 	"aim-oscar/util"
 	"encoding"
 	"encoding/binary"
+	"io"
 )
 
+// Buffer is a handy byte slice that reads from the front and writes on the end
 type Buffer struct {
 	d []byte
 }
 
+// Seek moves the read cursor forward. If the cursor is beyond the length of the byte
+// slice then the buffer slice is just replaced with an empty slice
+func (b *Buffer) Seek(n int) {
+	if n > len(b.d) {
+		b.d = make([]byte, 0)
+		return
+	}
+	b.d = b.d[n:]
+}
+
+func (b *Buffer) Read(d []byte) (int, error) {
+	if len(d) > len(b.d) {
+		return 0, io.EOF
+	}
+
+	n := copy(d, b.d[0:len(d)])
+	return n, nil
+}
+
+func (b *Buffer) ReadUint8() (uint8, error) {
+	if len(b.d) < 1 {
+		return 0, io.EOF
+	}
+	ret := uint8(b.d[0])
+	b.d = b.d[1:]
+	return ret, nil
+}
+
+func (b *Buffer) ReadUint16() (uint16, error) {
+	if len(b.d) < 2 {
+		return 0, io.EOF
+	}
+	ret := binary.BigEndian.Uint16(b.d[0:2])
+	b.d = b.d[2:]
+	return ret, nil
+}
+
+func (b *Buffer) ReadUint32() (uint32, error) {
+	if len(b.d) < 4 {
+		return 0, io.EOF
+	}
+	ret := binary.BigEndian.Uint32(b.d[0:4])
+	b.d = b.d[4:]
+	return ret, nil
+}
+
+func (b *Buffer) ReadUint64() (uint64, error) {
+	if len(b.d) < 8 {
+		return 0, io.EOF
+	}
+	ret := binary.BigEndian.Uint64(b.d[0:8])
+	b.d = b.d[8:]
+	return ret, nil
+}
+
+// ReadLPString reads a length-prefixed string. The first byte should be the string length
+// followed by that many bytes. Returns io.EOF if there are less bytes than indicated.
+func (b *Buffer) ReadLPString() (string, error) {
+	length, err := b.ReadUint8()
+	if err != nil {
+		return "", nil
+	}
+
+	if len(b.d) < int(length) {
+		return "", io.EOF
+	}
+
+	str := string(b.d[:length])
+	b.d = b.d[length:]
+	return str, nil
+}
+
 func (b *Buffer) WriteUint8(x uint8) {
 	b.d = append(b.d, x)
 }
@@ -33,6 +107,11 @@ func (b *Buffer) WriteString(x string) {
 	b.d = append(b.d, []byte(x)...)
 }
 
+func (b *Buffer) WriteLPString(x string) {
+	b.WriteUint8(uint8(len(x)))
+	b.WriteString(x)
+}
+
 func (b *Buffer) Write(x []byte) (int, error) {
 	b.d = append(b.d, x...)
 	return len(x), nil

oscar/buf_test.go

@@ -0,0 +1,55 @@
+package oscar
+
+import "testing"
+
+func fail(t *testing.T, e error, method string) {
+	if e != nil {
+		t.Errorf("invalid read from %s: %s", method, e.Error())
+	}
+}
+
+func TestBuffer(t *testing.T) {
+	b := Buffer{}
+
+	b.WriteUint8(uint8(1))
+	b.WriteUint16(uint16(2))
+	b.WriteUint32(uint32(3))
+	b.WriteUint64(uint64(4))
+
+	x1, err := b.ReadUint8()
+	fail(t, err, "ReadUint8")
+	if x1 != 1 {
+		t.Errorf("expected ReadUint8 to read 1, got %d", x1)
+	}
+
+	x2, err := b.ReadUint16()
+	fail(t, err, "ReadUint16")
+	if x2 != 2 {
+		t.Errorf("expected ReadUint16 to read 2, got %d", x2)
+	}
+
+	x3, err := b.ReadUint32()
+	fail(t, err, "ReadUint32")
+	if x3 != 3 {
+		t.Errorf("expected ReadUint32 to read 3, got %d", x3)
+	}
+
+	x4, err := b.ReadUint64()
+	fail(t, err, "ReadUint64")
+	if x4 != 4 {
+		t.Errorf("expected ReadUint64 to read 4, got %d", x4)
+	}
+}
+
+func TestBufferLPString(t *testing.T) {
+	b := Buffer{}
+
+	expectedStr := "This is a long string"
+	b.WriteLPString(expectedStr)
+
+	str, err := b.ReadLPString()
+	fail(t, err, "ReadLPString")
+	if str != expectedStr {
+		t.Errorf("expected to read %s, got %s", expectedStr, str)
+	}
+}