engine/schema: prepend algorithm to checksum during systemvm template registration (apache#12165)

* engine/schema: prepend algorithm to checksum during systemvm template registration

* Update utils/src/main/java/org/apache/cloudstack/utils/security/DigestHelper.java

Author: weizhouapache

engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java

@@ -606,7 +606,7 @@ private VMTemplateVO createTemplateObjectInDB(SystemVMTemplateDetails details) {
         template.setBits(64);
         template.setAccountId(Account.ACCOUNT_ID_SYSTEM);
         template.setUrl(details.getUrl());
-        template.setChecksum(details.getChecksum());
+        template.setChecksum(DigestHelper.prependAlgorithm(details.getChecksum()));
         template.setEnablePassword(false);
         template.setDisplayText(details.getName());
         template.setFormat(details.getFormat());
@@ -1079,7 +1079,7 @@ protected void updateRegisteredTemplateDetails(Long templateId, MetadataTemplate
     protected void updateTemplateUrlChecksumAndGuestOsId(VMTemplateVO templateVO,
                MetadataTemplateDetails templateDetails) {
         templateVO.setUrl(templateDetails.getUrl());
-        templateVO.setChecksum(templateDetails.getChecksum());
+        templateVO.setChecksum(DigestHelper.prependAlgorithm(templateDetails.getChecksum()));
         GuestOSVO guestOS = guestOSDao.findOneByDisplayName(templateDetails.getGuestOs());
         if (guestOS != null) {
             templateVO.setGuestOSId(guestOS.getId());

utils/src/main/java/org/apache/cloudstack/utils/security/DigestHelper.java

@@ -148,4 +148,19 @@ public static String calculateChecksum(File file) {
             throw new CloudRuntimeException(errMsg, e);
         }
     }
+
+    public static String prependAlgorithm(String checksum) {
+        if (StringUtils.isEmpty(checksum)) {
+            return checksum;
+        }
+        int checksumLength = checksum.length();
+        Map<String, Integer> paddingLengths = getChecksumLengthsMap();
+        for (Map.Entry<String, Integer> entry : paddingLengths.entrySet()) {
+            if (entry.getValue().equals(checksumLength)) {
+                String algorithm = entry.getKey();
+                return String.format("{%s}%s", algorithm, checksum);
+            }
+        }
+        return checksum;
+    }
 }