[Pkg-openssl-devel] Bug#524082: openssl: s_client ignores depth if certificate chain is valid

[Romain Francoise]

Package: openssl
Version: 0.9.8g-16

openssl s_client takes a depth parameter for the -verify option:

|   -verify depth
|       The verify depth to use. This specifies the maximum length of the
|       server certificate chain and turns on server certificate
|       verification.  Currently the verify operation continues after
|       errors so all the problems with a certificate chain can be seen. As
|       a side effect the connection will never fail due to a server
|       certificate verify failure.

This parameter is correctly enforced when the server certificate
chain is invalid, but it is not when the chain is valid.  In other
words, s_client doesn't verify the chain depth when all certificates
are valid.

It's because the depth check is implemented (in a verify callback)
in a conditional on the certificate status, if all certificates are
valid, the depth is never checked!  I would expect the verification
to fail if the chain is deeper than what I'm asking for, even if the
chain itself is valid.

(As a side note, the documentation is incorrect: when the chain is
invalid *and* deeper than the required depth, s_client doesn't
continue, it exits in the handshake.)

-- 
Romain Francoise <rfrancoise at debian.org>
http://people.debian.org/~rfrancoise/