Synch from mod_md github:

mod_md: tolerate missing revokeCert or keyChange resource

RFC 8555 §7.1 states:

  The server MUST provide "directory" and "newNonce" resources.

But RFC 8555 makes no explicit statement anywhere whether other
resources are, or are not, required (with the exception of
"newAuthz" which is optional).

Therefore it is possible that some ACME server implementations may
omit some resources; in particular those that are not an essential
part of the "order" workflow.  Indeed, I am working with one such
server implementation, which does not at this time implement
"keyChange".  mod_md refuses to interact with this server because it
is checking that a certain set of resources are defined in the
directory object - despite some of those resources not currently
being used.

Update the check to require only "newNonce", "newAccount" and
"newOrder".  Omit from the check and therefore tolerate the absense
of resources which are not always required: "revokeCert" and
"keyChange".

If mod_md implements revocation and/or key rollover in the future,
the availability of those features should be predicated on the
server's advertised capabilities.

https://github.com/icing/mod_md/commit/38ff597f3ccb3c942e68701fb185c6a68f0708e4

Submitted by: Fraser Tweedale <ftweedal redhat.com>
Github: closes #122

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1887148 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/changes-entries/mod_md-missing-resources.txt b/changes-entries/mod_md-missing-resources.txt
new file mode 100644 (file)
index 0000000..301d64f
--- /dev/null
+++ b/changes-entries/mod_md-missing-resources.txt
@@ -0,0 +1,2 @@
+  *) mod_md: Tolerate a missing "revokeCert" or "keyChange" resource.
+     [Fraser Tweedale <ftweedal redhat.com>]

diff --git a/modules/md/md_acme.c b/modules/md/md_acme.c
index c085ba351846e0e1eda725310571ba83e69e2770..e3702eb0ad4d4e421a9b80e84da1c041a3e227d0 100644 (file)
--- a/modules/md/md_acme.c
+++ b/modules/md/md_acme.c
@@ -726,8 +726,12 @@ static apr_status_t update_directory(const md_http_response_t *res, void *data)
         acme->api.v2.revoke_cert = md_json_dups(acme->p, json, "revokeCert", NULL);
         acme->api.v2.key_change = md_json_dups(acme->p, json, "keyChange", NULL);
         acme->api.v2.new_nonce = md_json_dups(acme->p, json, "newNonce", NULL);
-        if (acme->api.v2.new_account && acme->api.v2.new_order 
-            && acme->api.v2.revoke_cert && acme->api.v2.key_change
+        /* RFC 8555 only requires "directory" and "newNonce" resources.
+         * mod_md uses "newAccount" and "newOrder" so check for them.
+         * But mod_md does not use the "revokeCert" or "keyChange"
+         * resources, so tolerate the absense of those keys. */
+        if (acme->api.v2.new_account
+            && acme->api.v2.new_order
             && acme->api.v2.new_nonce) {
             acme->version = MD_ACME_VERSION_2;
         }