use default http client everywhere now since we're not modifying it

signer/contentsignaturepki/contentsignature.go

@@ -11,6 +11,7 @@ import (
 	"hash"
 	"io"
 	"math/big"
+	"net/http"
 	"time"
 
 	"github.com/mozilla-services/autograph/database"
@@ -187,7 +188,7 @@ func (s *ContentSigner) initEE(conf signer.Configuration) error {
 	default:
 		return fmt.Errorf("contentsignaturepki %q: failed to find suitable end-entity: %w", s.ID, err)
 	}
-	_, _, err = GetX5U(buildHTTPClient(), s.X5U)
+	_, _, err = GetX5U(http.DefaultClient, s.X5U)
 	if err != nil {
 		return fmt.Errorf("contentsignaturepki %q: failed to verify x5u: %w", s.ID, err)
 	}

signer/contentsignaturepki/contentsignature_test.go

@@ -9,6 +9,7 @@ package contentsignaturepki
 import (
 	"crypto/ecdsa"
 	"fmt"
+	"net/http"
 	"strings"
 	"testing"
 
@@ -74,7 +75,7 @@ func TestSign(t *testing.T) {
 			}
 
 			// verify the signature using the public key of the end entity
-			_, certs, err := GetX5U(buildHTTPClient(), s.X5U)
+			_, certs, err := GetX5U(http.DefaultClient, s.X5U)
 			if err != nil {
 				t.Fatalf("testcase %d failed to get X5U %q: %v", i, s.X5U, err)
 			}

signer/contentsignaturepki/upload.go

@@ -87,11 +87,6 @@ func writeLocalFile(data, name string, target *url.URL) error {
 	return os.WriteFile(filepath.Join(target.Path, name), []byte(data), 0755)
 }
 
-// buildHTTPClient returns the default HTTP.Client for fetching X5Us
-func buildHTTPClient() *http.Client {
-	return &http.Client{}
-}
-
 // GetX5U retrieves a chain file of certs from upload location, parses
 // and verifies it, then returns a byte slice of the response body and
 // a slice of parsed certificates.

signer/contentsignaturepki/x509.go

@@ -7,6 +7,7 @@ import (
 	"encoding/pem"
 	"fmt"
 	"math/big"
+	"net/http"
 	"net/url"
 	"time"
 
@@ -55,7 +56,7 @@ func (s *ContentSigner) makeAndUploadChain() error {
 	if err != nil {
 		return fmt.Errorf("failed to join x5u with chain name: %w", err)
 	}
-	_, _, err = GetX5U(buildHTTPClient(), newX5U)
+	_, _, err = GetX5U(http.DefaultClient, newX5U)
 	if err != nil {
 		return fmt.Errorf("failed to download new chain: %w", err)
 	}