diff options
author | Jeremy Harris <jgh146exb@wizmail.org> | 2018-09-18 15:05:59 +0100 |
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committer | Jeremy Harris <jgh146exb@wizmail.org> | 2018-09-18 16:28:50 +0100 |
commit | 5fd28bb83f80141b9f7671ed9ae3e1a4263134e3 (patch) | |
tree | 6eda547af7b413ca2cff8c01e31f79429370f072 /doc/doc-docbook | |
parent | 3fb3231cf83c8a9328499ea17b3663c1618210dc (diff) |
GnuTLS: simplify cert hostname checking
Diffstat (limited to 'doc/doc-docbook')
-rw-r--r-- | doc/doc-docbook/spec.xfpt | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt index a93b39474..8fde6397c 100644 --- a/doc/doc-docbook/spec.xfpt +++ b/doc/doc-docbook/spec.xfpt @@ -27773,7 +27773,7 @@ session with a client, you must set either &%tls_verify_hosts%& or apply to all TLS connections. For any host that matches one of these options, Exim requests a certificate as part of the setup of the TLS session. The contents of the certificate are verified by comparing it with a list of -expected certificates. +expected trust-anchors or certificates. These may be the system default set (depending on library version), an explicit file or, depending on library version, a directory, identified by @@ -27790,6 +27790,9 @@ openssl x509 -hash -noout -in /cert/file .endd where &_/cert/file_& contains a single certificate. +There is no checking of names of the client against the certificate +Subject Name or Subject Alternate Names. + The difference between &%tls_verify_hosts%& and &%tls_try_verify_hosts%& is what happens if the client does not supply a certificate, or if the certificate does not match any of the certificates in the collection named by @@ -27951,6 +27954,11 @@ The &%tls_verify_hosts%& and &%tls_try_verify_hosts%& options restrict certificate verification to the listed servers. Verification either must or need not succeed respectively. +The &%tls_verify_cert_hostnames%& option lists hosts for which additional +checks are made: that the host name (the one in the DNS A record) +is valid for the certificate. +The option defaults to always checking. + The &(smtp)& transport has two OCSP-related options: &%hosts_require_ocsp%&; a host-list for which a Certificate Status is requested and required for the connection to proceed. The default @@ -28256,7 +28264,7 @@ this is appropriate for a single system, using a self-signed certificate. DANE-TA usage is effectively declaring a specific CA to be used; this might be a private CA or a public, well-known one. A private CA at simplest is just a self-signed certificate (with certain -attributes) which is used to sign cerver certificates, but running one securely +attributes) which is used to sign server certificates, but running one securely does require careful arrangement. With DANE-TA, as implemented in Exim and commonly in other MTAs, the server TLS handshake must transmit the entire certificate chain from CA to server-certificate. |