Fix lint issues

tlstypes/certificate_server.go

-package tlstypes
-
-import (
-	"container/ring"
-	"context"
-	"crypto/tls"
-	"crypto/x509"
-	"errors"
-	"fmt"
-	"net"
-	"strconv"
-	"time"
-
-	"go.uber.org/zap"
-
-	"github.com/9seconds/mtg/config"
-)
-
-const (
-	connectionServerKeepCertificates = 5
-	connectionServerUpdateEvery      = 10 * time.Minute
-)
-
-type connectionServer struct {
-	nextWriteItem *ring.Ring
-	nextReadItem  *ring.Ring
-
-	ctx        context.Context
-	channelGet chan chan<- *x509.Certificate
-}
-
-func (c *connectionServer) fetch() (*x509.Certificate, error) {
-	addr := net.JoinHostPort(config.C.CloakHost, strconv.Itoa(config.C.CloakPort))
-	conn, err := tls.Dial("tcp", addr, &tls.Config{InsecureSkipVerify: true}) // nolint: gosec
-
-	if err != nil {
-		return nil, fmt.Errorf("cannot connect to the masked host: %w", err)
-	}
-
-	defer conn.Close()
-
-	if err = conn.Handshake(); err != nil {
-		return nil, fmt.Errorf("cannot perform tls handshake: %w", err)
-	}
-
-	certificates := conn.ConnectionState().PeerCertificates
-	if len(certificates) == 0 {
-		return nil, errors.New("no certificates is found")
-	}
-
-	return certificates[0], nil
-}
-
-func (c *connectionServer) run() {
-	logger := zap.S().Named("tls-connection-server")
-
-	ticker := time.NewTicker(connectionServerUpdateEvery)
-	defer ticker.Stop()
-
-	for {
-		select {
-		case <-c.ctx.Done():
-			return
-		case resp := <-c.channelGet:
-			resp <- c.nextReadItem.Value.(*x509.Certificate)
-			close(resp)
-
-			c.nextReadItem = c.nextReadItem.Next()
-		case <-ticker.C:
-			cert, err := c.fetch()
-			switch err {
-			case nil:
-				c.nextWriteItem.Value = cert
-				c.nextWriteItem = c.nextWriteItem.Next()
-			default:
-				logger.Warnw("cannot fetch certificates", "error", err)
-			}
-		}
-	}
-}

wrappers/stream/blockcipher.go

 			if err != nil {
 				return nil, fmt.Errorf("cannot read data: %w", err)
 			}
+
 			currentBuffer = append(currentBuffer, rv...)
 		}
 		cipher.decryptor.CryptBlocks(currentBuffer, currentBuffer)

wrappers/stream/buffered_reader.go

 	if err != nil {
 		return 0, err
 	}
+
 	b.buf.Write(res)
 
 	return b.flush(p)