util.x509: Only compare identity with oid-on-xmppAddr for XMPP services

[prosody.git] / util / x509.lua

diff --git a/util/x509.lua b/util/x509.lua
index 11f231a04b12f93882f9a138cd3b16423a5ca473..857f02a409087e3dc8716ca2e4c8ba6f91ae9d82 100644 (file)
--- a/util/x509.lua
+++ b/util/x509.lua
@@ -11,8 +11,8 @@
 -- IDN libraries complicate that.
 
 
--- [TLS-CERTS] - http://tools.ietf.org/html/draft-saintandre-tls-server-id-check-10
--- [XMPP-CORE] - http://tools.ietf.org/html/draft-ietf-xmpp-3920bis-18
+-- [TLS-CERTS] - http://tools.ietf.org/html/rfc6125
+-- [XMPP-CORE] - http://tools.ietf.org/html/rfc6120
 -- [SRV-ID]    - http://tools.ietf.org/html/rfc4985
 -- [IDNA]      - http://tools.ietf.org/html/rfc5890
 -- [LDAP]      - http://tools.ietf.org/html/rfc4519
@@ -21,6 +21,10 @@
 local nameprep = require "util.encodings".stringprep.nameprep;
 local idna_to_ascii = require "util.encodings".idna.to_ascii;
 local log = require "util.logger".init("x509");
+local pairs, ipairs = pairs, ipairs;
+local s_format = string.format;
+local t_insert = table.insert;
+local t_concat = table.concat;
 
 module "x509"
 
@@ -32,7 +36,7 @@ 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 4.4.1 and 4.4.2 of [TLS-CERTS]
+-- sections 6.4.1 and 6.4.2 of [TLS-CERTS]
 --
 -- A wildcard ("*") all by itself is allowed only as the left-most label
 local function compare_dnsname(host, asserted_names)
@@ -150,14 +154,16 @@ function verify_identity(host, service, cert)
        if ext[oid_subjectaltname] then
                local sans = ext[oid_subjectaltname];
 
-               -- Per [TLS-CERTS] 4.3, 4.4.4, "a client MUST NOT seek a match for a
+               -- 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 compare_xmppaddr(host, sans[oid_xmppaddr]) then return true end
+                       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
@@ -183,7 +189,7 @@ function verify_identity(host, service, cert)
        -- a dNSName subjectAltName (wildcards may apply for, and receive,
        -- cat treats)
        --
-       -- Per [TLS-CERTS] 1.5, a CN-ID is the Common Name from a cert subject
+       -- 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
@@ -200,7 +206,7 @@ function verify_identity(host, service, cert)
        end
 
        if cn then
-               -- Per [TLS-CERTS] 4.4.4, follow the comparison rules for dNSName SANs.
+               -- Per [TLS-CERTS] 6.4.4, follow the comparison rules for dNSName SANs.
                return compare_dnsname(host, { cn })
        end