[SOLR-13238] BlobHandler generates non-padded md5

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 6.0, 6.6.5, 7.0, 7.6, 7.7
• Fix Version/s: 8.3
• Component/s: blobstore
• Assignee: Jan Høydahl
• Reporter: Jeff Walraven
• Created: 09/Feb/19 16:39
• Updated: 17/Sep/19 00:10
• Resolved: 14/Sep/19 20:48

Description

Introduced in SOLR-6787

The blob handler currently uses the following logic for generating/storing the md5 for uploads:

MessageDigest m = MessageDigest.getInstance("MD5");
m.update(payload.array(), payload.position(), payload.limit());
String md5 = new BigInteger(1, m.digest()).toString(16);

Unfortunately, this method does not provide padding for any md5 with less than 0x10 for its most significant byte. This means that on many occasions it could end up with a md5 hash of 31 characters instead of 32.

I have opened a PR with the following recommended change:

String md5 = new String(Hex.encodeHex(m.digest()));

Issue Links

• links to: GitHub Pull Request #570