CI Addition (ECH): Check only the public SNI is visible#10542
CI Addition (ECH): Check only the public SNI is visible#10542sebastian-carpenter wants to merge 1 commit into
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Pull request overview
This PR fixes a bug in ECH (Encrypted Client Hello) outer ClientHello handling so that the public SNI is always substituted into the outer ClientHello (regardless of echAccepted state or innerCount), preventing leakage of the private SNI on the wire. A corresponding wire-bytes test is added.
Changes:
- Simplify the condition in
TLSX_EchChangeSNIto swap the SNI whenever the ECH extension type isECH_TYPE_OUTER. - Add
test_wolfSSL_Tls13_ECH_wire_snicovering both ECH-accept and ECH-reject paths, forcing a HelloRetryRequest and asserting the public name appears and the private name does not appear on the wire for both CH1 and CH2.
Reviewed changes
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| File | Description |
|---|---|
| src/tls.c | Always swap SNI to the public name when processing the outer ClientHello, removing extra gating conditions. |
| tests/api.c | New ECH wire-SNI test (accept + reject paths with HRR) registered in testCases. |
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retest this please |
| { | ||
| EXPECT_DECLS; | ||
| test_ssl_memio_ctx test_ctx; | ||
| WOLFSSL_CTX* tempCtx = NULL; |
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Reduce the scope - put declarations down in block where used.
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fixed, moved them down to !accept block.
| WOLFSSL_ERROR_WANT_READ); | ||
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| /* CH2 wire bytes: same property must hold */ | ||
| ExpectNotNull(mymemmem(test_ctx.s_buff, test_ctx.s_len, |
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Can we expect echCbTestPublicName to be at a specific location?
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Yes! Removed memmem check and replaced it with ech_find_extension to only perform the check at the SNI extension.
Once more extensions are added to ECH this test should be refactored to check that those are swapped out as well.
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Rebased to get Added a sanity check at the end of the test to make sure ECH is suceeding or failing as expected. |
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Jenkins retest this please |
Description
Added a test to check that the SNI in the outer ClientHello is always the public SNI. Other checks exist to verify the inner SNI is correct.
Corrected
TLSX_EchChangeSNIto always swap the SNI when it is processing the outer hello.Testing
Added
test_wolfSSL_Tls13_ECH_wire_sniwhich forces a HelloRetryRequest with either ech rejection or acceptance.Checklist