| commit | 8ab77eefc83ea4d879fd0afe162b0be080d5de06 | [log] [tgz] |
|---|---|---|
| author | David Benjamin <davidben@google.com> | Thu Dec 21 22:34:59 2023 -0500 |
| committer | Boringssl LUCI CQ <boringssl-scoped@luci-project-accounts.iam.gserviceaccount.com> | Tue Jan 09 18:47:08 2024 +0000 |
| tree | 9d1fdd995598c3de8f24e9e4241053081a57eec4 | |
| parent | 7a813621dac6878ab53b6ed7392939a8982226e8 [diff] |
Fix error-handling convention in x509_vfy.c and avoid -1 returns This CL makes two changes. First, it removes the couple of places where X509_verify_cert may return -1 and switches to our standard 0/1 return convention. The only -1 cases were get_issuer returning < 0 and the caller error cases at the top. It seems implausible that any caller would care about the latter and the former is actually impossible. get_issuer never returns < 0. Second, OpenSSL's original implementation did not follow the usual error-handling convention. The usual convention is that there's a cleanup epilog, and a variable (usually called 'ret' or 'ok') that stores the return value. This variable is initialized in the failure case and may only be modified immediately before a goto or when falling through to the epilog. This allows error conditions to simply 'goto err' and rely on the variable's value. X509_verify_cert instead overwrite 'ok' throughout the function, which is tedious and error-prone. Fix this to follow the usual convention. Also remove uses of this pattern when there isn't anything to cleanup. As part of this cleanup, we fix a near miss: the three cert_self_signed call sites did not correctly account for this non-standard pattern. Fortunately (as demonstrated by existing unit tests), the first call site is fine. The remainder are only called on "trusted" certificates from the X509_STORE. An attacker with control over trust anchors already controls certificate verification, so this is moot. Moreover, all such certificates first go through get_issuer, which calls X509_check_issued, which already handles EXFLAG_INVALID, so the error condition was redundant. Update-Note: X509_verify_cert no longer returns -1 on some error conditions, only zero. Change-Id: I88d5e845cd4cb8f48d5c5df6782bf6730c682642 Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/65067 Auto-Submit: David Benjamin <davidben@google.com> Commit-Queue: Bob Beck <bbe@google.com> Reviewed-by: Bob Beck <bbe@google.com>
BoringSSL is a fork of OpenSSL that is designed to meet Google's needs.
Although BoringSSL is an open source project, it is not intended for general use, as OpenSSL is. We don't recommend that third parties depend upon it. Doing so is likely to be frustrating because there are no guarantees of API or ABI stability.
Programs ship their own copies of BoringSSL when they use it and we update everything as needed when deciding to make API changes. This allows us to mostly avoid compromises in the name of compatibility. It works for us, but it may not work for you.
BoringSSL arose because Google used OpenSSL for many years in various ways and, over time, built up a large number of patches that were maintained while tracking upstream OpenSSL. As Google's product portfolio became more complex, more copies of OpenSSL sprung up and the effort involved in maintaining all these patches in multiple places was growing steadily.
Currently BoringSSL is the SSL library in Chrome/Chromium, Android (but it's not part of the NDK) and a number of other apps/programs.
Project links:
There are other files in this directory which might be helpful: