MULTIARCH-4568: Print release image arch and default arch when the payload is multi

cmd/openshift-install/version.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"os"
+	"strings"
 
 	"github.com/spf13/cobra"
 
@@ -33,6 +34,14 @@ func runVersionCmd(cmd *cobra.Command, args []string) error {
 	if image, err := releaseimage.Default(); err == nil {
 		fmt.Printf("release image %s\n", image)
 	}
-	fmt.Printf("release architecture %s\n", version.DefaultArch())
+	releaseArch, err := version.ReleaseArchitecture()
+	if err != nil {
+		return err
+	}
+	fmt.Printf("release architecture %s\n", releaseArch)
+	if strings.Contains(releaseArch, "multi") || strings.Contains(releaseArch, "unknown") {
+		fmt.Printf("default architecture %s\n", version.DefaultArch())
+	}
+
 	return nil
 }

pkg/version/version.go

@@ -3,8 +3,11 @@ package version
 
 import (
 	"fmt"
+	"os"
 	"strings"
 
+	"github.com/sirupsen/logrus"
+
 	"github.com/openshift/installer/pkg/types"
 )
 
@@ -34,12 +37,23 @@ var (
 	// Set in hack/build.sh.
 	defaultArch = "amd64"
 
+	// releaseArchitecture is the architecture of the release payload: multi, amd64, arm64, ppc64le, or s390x.
+	// we don't know the releaseArchitecure by default "".
+	releaseArchitecture = ""
+
 	// defaultReleaseInfoPadded may be replaced in the binary with Release Metadata: Version that overrides defaultVersion as
 	// a null-terminated string within the allowed character length. This allows a distributor to override the payload
 	// location without having to rebuild the source.
 	defaultVersionPadded = "\x00_RELEASE_VERSION_LOCATION_\x00XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\x00"
 	defaultVersionPrefix = "\x00_RELEASE_VERSION_LOCATION_\x00"
 	defaultVersionLength = len(defaultVersionPadded)
+
+	// releaseArchitecturesPadded may be replaced in the binary with Release Image Architecture(s): RELEASE_ARCHITECTURE that overrides releaseArchitecture as
+	// a null-terminated string within the allowed character length. This allows a distributor to override the payload
+	// location without having to rebuild the source.
+	releaseArchitecturesPadded = "\x00_RELEASE_ARCHITECTURE_LOCATION_\x00XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX\x00"
+	releaseArchitecturesPrefix = "\x00_RELEASE_ARCHITECTURE_LOCATION_\x00"
+	releaseArchitecturesLength = len(releaseArchitecturesPadded)
 )
 
 // String returns the human-friendly representation of the version.
@@ -71,6 +85,46 @@ func Version() (string, error) {
 	return releaseName, nil
 }
 
+// ReleaseArchitecture returns the release image cpu architecture version.
+func ReleaseArchitecture() (string, error) {
+	ri, okRI := os.LookupEnv("OPENSHIFT_INSTALL_RELEASE_IMAGE_OVERRIDE")
+	if okRI {
+		logrus.Warnf("Found override for release image (%s). Release Image Architecture is unknown", ri)
+		return "unknown", nil
+	}
+	if strings.HasPrefix(releaseArchitecturesPadded, releaseArchitecturesPrefix) {
+		logrus.Warn("Release Image Architecture not detected. Release Image Architecture is unknown")
+		return "unknown", nil
+	}
+	nullTerminator := strings.IndexByte(releaseArchitecturesPadded, '\x00')
+	if nullTerminator == -1 {
+		// the binary has been altered, but we didn't find a null terminator within the release architecture constant which is an error
+		return Raw, fmt.Errorf("release architecture location was replaced but without a null terminator before %d bytes", releaseArchitecturesLength)
+	}
+	if nullTerminator > len(releaseArchitecturesPadded) {
+		// the binary has been altered, but the null terminator is *longer* than the constant encoded in the binary
+		return Raw, fmt.Errorf("release architecture location contains no null-terminator and constant is corrupted")
+	}
+	releaseArchitecture = releaseArchitecturesPadded[:nullTerminator]
+	if len(releaseArchitecture) == 0 {
+		// the binary has been altered, but the replaced release architecture is empty which is incorrect
+		return Raw, fmt.Errorf("release architecture was incorrectly replaced during extract")
+	}
+	return cleanArch(releaseArchitecture), nil
+}
+
+// cleanArch oc will embed linux/<arch> or multi (linux/<arch>) we want to clean this up so validation can more cleanly use this method.
+// multi (linux/amd64) -> multi
+// linux/amd64 -> amd64
+// linux/<arch> -> <arch>.
+func cleanArch(releaseArchitecture string) string {
+	if strings.HasPrefix(releaseArchitecture, "multi") {
+		return "multi"
+	}
+	// remove 'linux/', we just want <arch>
+	return strings.ReplaceAll(releaseArchitecture, "linux/", "")
+}
+
 // DefaultArch returns the default release architecture
 func DefaultArch() types.Architecture {
 	return types.Architecture(defaultArch)