Skip to content

require scram server nonce to extend the client nonce #896

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
dxbjavid wants to merge 1 commit into
base: master
Choose a base branch
from
Open

require scram server nonce to extend the client nonce #896

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 3 additions & 2 deletions httpclient5/src/main/java/org/apache/hc/client5/http/impl/auth/ScramScheme.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -289,9 +289,10 @@ public void processChallenge(
this.state = State.FAILED;
throw new MalformedChallengeException("SCRAM server-first missing r/s/i");
}
if (this.clientNonce == null || !r.startsWith(this.clientNonce)) {
if (this.clientNonce == null || !r.startsWith(this.clientNonce)
|| r.length() <= this.clientNonce.length()) {
this.state = State.FAILED;
throw new AuthenticationException("SCRAM server nonce does not start with client nonce");
throw new AuthenticationException("SCRAM server nonce does not extend client nonce");
}

try {
Expand Down
30 changes: 30 additions & 0 deletions httpclient5/src/test/java/org/apache/hc/client5/http/impl/auth/TestScramScheme.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -257,6 +257,36 @@ void strictScram_invalidServerNonce_rejectedAt401() throws Exception {
assertTrue(scheme.isChallengeComplete());
}

@Test
void strictScram_serverNonceNotExtended_rejectedAt401() throws Exception {
final ScramScheme scheme = new ScramScheme();
final BasicCredentialsProvider creds = new BasicCredentialsProvider();
creds.setCredentials(new AuthScope(HOST, REALM, scheme.getName()),
new UsernamePasswordCredentials(USER, PASS.toCharArray()));
final HttpClientContext ctx = HttpClientContext.create();

scheme.processChallenge(HOST, true,
new AuthChallenge(ChallengeType.TARGET, scheme.getName(),
new BasicNameValuePair("realm", REALM)),
ctx);
assertTrue(scheme.isResponseReady(HOST, creds, ctx));

final String authz1 = scheme.generateAuthResponse(HOST, null, ctx);
final String clientFirstBare = deb64s(splitHeader(authz1).get("data")).substring("n,,".length());
final String clientNonce = parseCsvAttrs(clientFirstBare).get("r");

// Server echoes the client nonce verbatim, contributing no server nonce of its own.
final String serverFirst = "r=" + clientNonce + ",s=" + b64("salt".getBytes(StandardCharsets.UTF_8)) + ",i=4096";
final AuthenticationException ex = assertThrows(AuthenticationException.class, () ->
scheme.processChallenge(HOST, true,
new AuthChallenge(ChallengeType.TARGET, scheme.getName(),
new BasicNameValuePair("sid", SID),
new BasicNameValuePair("data", b64(serverFirst.getBytes(StandardCharsets.UTF_8)))),
ctx));
assertTrue(ex.getMessage().toLowerCase(Locale.ROOT).contains("nonce"));
assertTrue(scheme.isChallengeComplete());
}

@Test
void strictScram_minIterations_enforced() throws Exception {
final ScramScheme scheme = new ScramScheme(4096, 4096, 100000, null);
Expand Down
Loading