diff options
Diffstat (limited to 'util/x509.lua')
| -rw-r--r-- | util/x509.lua | 51 |
1 files changed, 7 insertions, 44 deletions
diff --git a/util/x509.lua b/util/x509.lua index 9ecb5b60..6d856be0 100644 --- a/util/x509.lua +++ b/util/x509.lua @@ -11,7 +11,8 @@ -- IDN libraries complicate that. --- [TLS-CERTS] - https://www.rfc-editor.org/rfc/rfc6125.html +-- [TLS-CERTS] - https://www.rfc-editor.org/rfc/rfc6125.html -- Obsolete +-- [TLS-IDENT] - https://www.rfc-editor.org/rfc/rfc9525.html -- [XMPP-CORE] - https://www.rfc-editor.org/rfc/rfc6120.html -- [SRV-ID] - https://www.rfc-editor.org/rfc/rfc4985.html -- [IDNA] - https://www.rfc-editor.org/rfc/rfc5890.html @@ -35,10 +36,8 @@ local oid_subjectaltname = "2.5.29.17"; -- [PKIX] 4.2.1.6 local oid_xmppaddr = "1.3.6.1.5.5.7.8.5"; -- [XMPP-CORE] local oid_dnssrv = "1.3.6.1.5.5.7.8.7"; -- [SRV-ID] --- Compare a hostname (possibly international) with asserted names --- extracted from a certificate. --- This function follows the rules laid out in --- sections 6.4.1 and 6.4.2 of [TLS-CERTS] +-- Compare a hostname (possibly international) with asserted names extracted from a certificate. +-- This function follows the rules laid out in section 6.3 of [TLS-IDENT] -- -- A wildcard ("*") all by itself is allowed only as the left-most label local function compare_dnsname(host, asserted_names) @@ -159,61 +158,25 @@ local function verify_identity(host, service, cert) if ext[oid_subjectaltname] then local sans = ext[oid_subjectaltname]; - -- Per [TLS-CERTS] 6.3, 6.4.4, "a client MUST NOT seek a match for a - -- reference identifier if the presented identifiers include a DNS-ID - -- SRV-ID, URI-ID, or any application-specific identifier types" - local had_supported_altnames = false - if sans[oid_xmppaddr] then - had_supported_altnames = true if service == "_xmpp-client" or service == "_xmpp-server" then if compare_xmppaddr(host, sans[oid_xmppaddr]) then return true end end end if sans[oid_dnssrv] then - had_supported_altnames = true -- Only check srvNames if the caller specified a service if service and compare_srvname(host, service, sans[oid_dnssrv]) then return true end end if sans["dNSName"] then - had_supported_altnames = true if compare_dnsname(host, sans["dNSName"]) then return true end end - - -- We don't need URIs, but [TLS-CERTS] is clear. - if sans["uniformResourceIdentifier"] then - had_supported_altnames = true - end - - if had_supported_altnames then return false end - end - - -- Extract a common name from the certificate, and check it as if it were - -- a dNSName subjectAltName (wildcards may apply for, and receive, - -- cat treats) - -- - -- Per [TLS-CERTS] 1.8, a CN-ID is the Common Name from a cert subject - -- which has one and only one Common Name - local subject = cert:subject() - local cn = nil - for i=1,#subject do - local dn = subject[i] - if dn["oid"] == oid_commonname then - if cn then - log("info", "Certificate has multiple common names") - return false - end - - cn = dn["value"]; - end end - if cn then - -- Per [TLS-CERTS] 6.4.4, follow the comparison rules for dNSName SANs. - return compare_dnsname(host, { cn }) - end + -- Per [TLS-IDENT] ignore the Common Name + -- The server identity can only be expressed in the subjectAltNames extension; + -- it is no longer valid to use the commonName RDN, known as CN-ID in [TLS-CERTS]. -- If all else fails, well, why should we be any different? return false |