openbsd/src/lib/libcrypto/man/BIO_push.3, branch OPENBSD_7_9A mirror of https://github.com/libressl/openbsd.git
https://git.lua4.win/openbsd/atom?h=OPENBSD_7_92025-06-08T22:40:31+00:00.Lb libcrypto ; OK tb@2025-06-08T22:40:31+00:00schwarze2025-06-08T22:40:31+00:00urn:sha1:8be86af02fed1bda350c8dd14ee064cb66e3b0f5add a CAVEATS section warning the user to not create cycles;2022-12-16T16:02:17+00:00schwarze2022-12-16T16:02:17+00:00urn:sha1:dd85159117310f95b434b12d239e64779877d2cd
OK tb@
Revert BIO_push(3) cycle prevention (bio_lib.c rev. 1.42).2022-12-16T13:41:55+00:00schwarze2022-12-16T13:41:55+00:00urn:sha1:276664d6605ecf92a3b35c4f8c22ebec09a912c1
jsing@ worries that cycle prevention might increase risk because
software that is not checking return values (and indeed, not checking
is likely common in practice) might silently behave incorrectly
with cycle prevention whereas without, it will likely either crash
right away through infinite recursion or at least hang in an infinite
loop when trying to use the cyclic chain, in both cases making it
likely that the bug will be found and fixed.
Besides, tb@ points out that BIO_set_next(3) ought to behave as
similarly as possible to BIO_push(3), but adding cycle prevention
to BIO_set_next(3) would be even less convincing because that
function does not provide a return value, encouraging users to
expect that it will always succeed. While a safe idiom for checking
the success of BIO_set_next(3) could easily be designed, let's be
realistic: application software would be highly unlikely to pick up
such an idiom.
Fix copy-paste error that left a paragraph ending in a comma2022-12-08T11:33:58+00:00tb2022-12-08T11:33:58+00:00urn:sha1:77de0e5f3c23f4957bd4027e4ff78cce33dacf14Improve the implementation of BIO_push(3) such that it changes nothing2022-12-07T23:08:47+00:00schwarze2022-12-07T23:08:47+00:00urn:sha1:eab11350130a507ed42936e4a3c922f3930a163e
and reports failure if a call would result in a cycle.
The algorithm used was originally suggested by jsing@.
Feedback and OK tb@.
Add references to the BIO_{push,pop}(3) example2022-12-07T22:30:15+00:00tb2022-12-07T22:30:15+00:00urn:sha1:54623fd72233c5a1c31b5dd154a6cd2e370a29fd
The reader may not know what digest BIOs, Base64 BIOs and file BIOs are
and the relevant function names are non-obvious, hence it's not entirely
trivial to find the manuals where they are explained. With these references
a reader should be able to turn the example into actual code.
ok schwarze
Major rewrite for accuracy and clarity, and document BIO_set_next(3).2022-12-06T21:13:01+00:00schwarze2022-12-06T21:13:01+00:00urn:sha1:bcbb0a6883f1cfe1369eaeec3a6295d9919b9305
Feedback and OK tb@.
Drop 'perhaps a little', plus grammar and spelling nits2022-12-02T22:58:56+00:00tb2022-12-02T22:58:56+00:00urn:sha1:ed495f126a1e6e5dab84c2e136a4399bbaa74752
BIO_push() and BIO_pop() are misnamed. No need to gently and politely
suggest that their 'names [...] are perhaps a little misleading'.
found a complete archive of SSLeay-0.4 to SSLeay-0.8.1b tarballs2018-03-27T17:35:50+00:00schwarze2018-03-27T17:35:50+00:00urn:sha1:30d10c511917e0e339dec931667fc4b6eb014430
on the web, so fix up SSLeay HISTORY accordingly
bio.h HISTORY up to SSLeay 0.8.1b; researched from OpenSSL git2018-03-20T19:33:16+00:00schwarze2018-03-20T19:33:16+00:00urn:sha1:ae0b49ea2ef31eb81278600ca853df20ac03b498