Don't forget to include intermediate ACME certificate

Thanks to Konstantinos Kallas

src/ejabberd_acme.erl

@@ -331,16 +331,20 @@ create_new_certificate(CAUrl, {DomainName, AllSubDomains}, PrivateKey) ->
 	     {<<"notBefore">>, NotBefore},
 	     {<<"NotAfter">>, NotAfter}
 	    ],
-	{ok, {_CertUrl, Certificate}, _Nonce1} = 
+	{ok, {IssuerCertLink, Certificate}, _Nonce1} =
 	    ejabberd_acme_comm:new_cert(Dirs, PrivateKey, Req, Nonce0),
 
 	DecodedCert = public_key:pkix_decode_cert(list_to_binary(Certificate), plain),	
 	PemEntryCert = public_key:pem_entry_encode('Certificate', DecodedCert),
 
+	{ok, IssuerCert, _Nonce2} = ejabberd_acme_comm:get_issuer_cert(IssuerCertLink),
+	DecodedIssuerCert = public_key:pkix_decode_cert(list_to_binary(IssuerCert), plain),
+	PemEntryIssuerCert = public_key:pem_entry_encode('Certificate', DecodedIssuerCert),
+
 	{_, CSRKeyKey} = jose_jwk:to_key(CSRKey),
 	PemEntryKey = public_key:pem_entry_encode('ECPrivateKey', CSRKeyKey),
 
-	PemCertKey = public_key:pem_encode([PemEntryKey, PemEntryCert]),
+	PemCertKey = public_key:pem_encode([PemEntryKey, PemEntryCert, PemEntryIssuerCert]),
 
 	{ok, DomainName, PemCertKey}
     catch		     
@@ -1100,13 +1104,13 @@ save_certificate({ok, DomainName, Cert}) ->
 	%% that there is no certificate saved if it cannot be added in
 	%% certificate persistent storage
 	write_cert(CertificateFile, Cert, DomainName),
+	ok = ejabberd_pkix:add_certfile(CertificateFile),
 	DataCert = #data_cert{
 		      domain = DomainName,
 		      pem = Cert,
 		      path = CertificateFile
 		     },
 	add_certificate_persistent(DataCert),
-	ok = ejabberd_pkix:add_certfile(CertificateFile),
 	{ok, DomainName, saved}
     catch
 	throw:Throw ->

src/ejabberd_acme_comm.erl

@@ -15,7 +15,8 @@
 	 %% Certificate
 	 new_cert/4,
          get_cert/1,
-         revoke_cert/4
+         revoke_cert/4,
+	 get_issuer_cert/1
          %% Not yet implemented
 	 %% key_roll_over/5
          %% delete_authz/3
@@ -124,7 +125,7 @@ complete_challenge({CAUrl, AuthzId, ChallId}, PrivateKey, Req, Nonce) ->
 new_cert(Dirs, PrivateKey, Req, Nonce) ->
     #{"new-cert" := Url} = Dirs,
     EJson = {[{<<"resource">>, <<"new-cert">>}] ++ Req},
-    prepare_post_request(Url, PrivateKey, EJson, Nonce, fun get_response_location/1,
+    prepare_post_request(Url, PrivateKey, EJson, Nonce, fun get_response_link_up/1,
 			 "application/pkix-cert").
 
 -spec get_cert({url(), string()}) -> {ok, list(), nonce()} | {error, _}.
@@ -140,6 +141,9 @@ revoke_cert(Dirs, PrivateKey, Req, Nonce) ->
     prepare_post_request(Url, PrivateKey, EJson, Nonce, fun get_response/1,
                          "application/pkix-cert").
 
+-spec get_issuer_cert(url()) -> {ok, list(), nonce()} | {error, _}.
+get_issuer_cert(IssuerCertUrl) ->
+    prepare_get_request(IssuerCertUrl, fun get_response/1, "application/pkix-cert").
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%
@@ -172,7 +176,11 @@ get_response_location({ok, Head, Return}) ->
     NewNonce = get_nonce(Head),
     {ok, {Location, Return}, NewNonce}.
 
-
+-spec get_response_link_up({ok, proplist(), proplist()}) -> {ok, {url(), proplist()}, nonce()}.
+get_response_link_up({ok, Head, Return}) ->
+    LinkUp = get_link_up(Head),
+    NewNonce = get_nonce(Head),
+    {ok, {LinkUp, Return}, NewNonce}.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%
@@ -332,14 +340,21 @@ get_location(Head) ->
 	none -> none
     end.
 
-%% Very bad way to extract this
-%% TODO: Find a better way
 -spec get_tos(proplist()) -> url() | 'none'.
 get_tos(Head) ->
+    get_header_link(Head, "\"terms-of-service\"").
+
+-spec get_link_up(proplist()) -> url() | 'none'.
+get_link_up(Head) ->
+    get_header_link(Head, "rel=\"up\"").
+
+%% TODO: Find a more reliable way to extract this
+-spec get_header_link(proplist(), string()) -> url() | 'none'.
+get_header_link(Head, Suffix) ->
     try
 	[{_, Link}] = [{K, V} || {K, V} <- Head,
 				 K =:= "link" andalso
-				     lists:suffix("\"terms-of-service\"", V)],
+				     lists:suffix(Suffix, V)],
 	[Link1, _] = string:tokens(Link, ";"),
 	Link2 = string:strip(Link1, left, $<),
 	string:strip(Link2, right, $>)