Added session duration metrics with device analytics along with device

analytics metrics in the DB to aggregate and DeviceID abuse prevention

3 files changed, 102 insertions, 3 deletions

diff --git a/internal/server/api/api.go b/internal/server/api/api.go
index 8b1d711..5159186 100644
--- a/internal/server/api/api.go
+++ b/internal/server/api/api.go
@@ -5,10 +5,12 @@ import (
 	"context"
 	"crypto/ed25519"
 	"database/sql"
+	"encoding/binary"
 	"fmt"
 	"log/slog"
 	"strconv"
 	"strings"
+	"sync"
 
 	"github.com/kyren223/eko/internal/data"
 	"github.com/kyren223/eko/internal/packet"
@@ -34,7 +36,7 @@ func SendMessage(ctx context.Context, sess *session.Session, request *packet.Sen
 
 	if len(request.Content) > packet.MaxMessageBytes {
 		return &packet.Error{Error: fmt.Sprintf(
-			"message conent must not exceed %v bytes",
+			"message content must not exceed %v bytes",
 			packet.MaxMessageBytes,
 		)}
 	}
@@ -1647,7 +1649,57 @@ func sendInitialAuthPackets(ctx context.Context, sess *session.Session) bool {
 	return success
 }
 
+var (
+	ipDeviceID map[uint32]string = map[uint32]string{}
+	deviceIdMu sync.Mutex
+)
+
 func DeviceAnalytics(ctx context.Context, sess *session.Session, request *packet.DeviceAnalytics) packet.Payload {
-	// TODO: implement this
-	return &ErrNotImplemented
+	const DeviceIdLength = 64
+
+	if len(request.DeviceID) != DeviceIdLength {
+		return &packet.Error{Error: fmt.Sprintf(
+			"DeviceID must be exactly %v bytes", DeviceIdLength,
+		)}
+	}
+
+	for _, c := range request.DeviceID {
+		if (c < '0' || c > '9') && (c < 'a' || c > 'f') {
+			return &packet.Error{
+				Error: "DeviceID must be all lowercase hexadecimal",
+			}
+		}
+	}
+
+	ip := binary.BigEndian.Uint32(sess.Addr().IP.To4())
+	deviceIdMu.Lock()
+	if deviceId, ok := ipDeviceID[ip]; ok {
+		if request.DeviceID != deviceId {
+			slog.WarnContext(ctx, "device ID mismatch", "existing_device_id", deviceId, "request_device_id", request.DeviceID)
+			request.DeviceID = deviceId
+			// Override the request to use the known ID
+			// This avoids abuse
+		}
+	} else {
+		ipDeviceID[ip] = request.DeviceID
+	}
+	deviceIdMu.Unlock()
+
+	if !IsValidAnalytics(ctx, request) {
+		// This is either malicious or we should actually add new variations
+		// In either case the client shouldn't need a response
+		return nil
+	}
+
+	sess.SetAnalytics(request)
+	queries := data.New(db)
+	queries.SetDeviceAnalytics(ctx, data.SetDeviceAnalyticsParams{
+		DeviceID:  request.DeviceID,
+		Os:        &request.OS,
+		Arch:      &request.Arch,
+		Term:      &request.Term,
+		Colorterm: &request.Colorterm,
+	})
+
+	return nil
 }
diff --git a/internal/server/api/helpers.go b/internal/server/api/helpers.go
index ea192df..6993d0a 100644
--- a/internal/server/api/helpers.go
+++ b/internal/server/api/helpers.go
@@ -3,6 +3,7 @@ package api
 import (
 	"context"
 	"log/slog"
+	"slices"
 	"strings"
 	"time"
 
@@ -190,3 +191,38 @@ func getNotifications(ctx context.Context, userId snowflake.ID) (packet.Notifica
 	}
 	return items, nil
 }
+
+var (
+	ValidOs        = []string{"linux", "darwin", "windows", "android", ""}
+	ValidArch      = []string{"amd64", "arm64", "386", ""}
+	ValidTerm      = []string{"xterm-256color", "tmux-256color", "xterm-ghostty", "xterm-kitty", "alacritty", "foot", "xterm", ""}
+	ValidColorterm = []string{"truecolor", "24bit", ""}
+)
+
+func IsValidAnalytics(ctx context.Context, analytics *packet.DeviceAnalytics) bool {
+	if analytics == nil {
+		return false
+	}
+
+	if !slices.Contains(ValidOs, analytics.OS) {
+		slog.WarnContext(ctx, "unrecognized analytics value", "os", analytics.OS, "analytics", analytics)
+		return false
+	}
+
+	if !slices.Contains(ValidArch, analytics.Arch) {
+		slog.WarnContext(ctx, "unrecognized analytics value", "arch", analytics.Arch, "analytics", analytics)
+		return false
+	}
+
+	if !slices.Contains(ValidTerm, analytics.Term) {
+		slog.WarnContext(ctx, "unrecognized analytics value", "term", analytics.Term, "analytics", analytics)
+		return false
+	}
+
+	if !slices.Contains(ValidColorterm, analytics.Colorterm) {
+		slog.WarnContext(ctx, "unrecognized analytics value", "colorterm", analytics.Colorterm, "analytics", analytics)
+		return false
+	}
+
+	return true
+}
diff --git a/internal/server/api/migrations/20250717130820_device_analytics.sql b/internal/server/api/migrations/20250717130820_device_analytics.sql
new file mode 100644
index 0000000..b4797a4
--- /dev/null
+++ b/internal/server/api/migrations/20250717130820_device_analytics.sql
@@ -0,0 +1,11 @@
+-- +goose Up
+CREATE TABLE IF NOT EXISTS device_analytics (
+    device_id TEXT PRIMARY KEY,
+    os TEXT,
+    arch TEXT,
+    term TEXT,
+    colorterm TEXT
+);
+
+-- +goose Down
+DROP TABLE IF EXISTS device_analytics;