Crash in Erlang/OTP 28: {function_clause, [{public_key,get_asn1_module, ['ExtensionRequest']

[badlop]

In ejabberd compiled with Erlang/OTP 28.0, requesting a certificate using ACME crashes with this message:

2025-06-04 10:17:37.549313+02:00 [error] ** Generic server ejabberd_acme terminating 
** Last message in was {request,[<<"example.myserver.com">>]}
** When Server state == {state}
** Reason for termination ==
** {function_clause,
       [{public_key,get_asn1_module,
            ['SubjectAltName'],
            [{file,"public_key.erl"},{line,576}]},
        {public_key,der_encode,2,[{file,"public_key.erl"},{line,804}]},
        {p1_acme,generate_csr,2,
            [{file,
                 "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
             {line,770}]},

2025-06-04 10:17:37.549313+02:00 [error] ** Generic server ejabberd_acme terminating 
** Last message in was {request,[<<"example.myserver.com">>]}
** When Server state == {state}
** Reason for termination ==
** {function_clause,
       [{public_key,get_asn1_module,
            ['SubjectAltName'],
            [{file,"public_key.erl"},{line,576}]},
        {public_key,der_encode,2,[{file,"public_key.erl"},{line,804}]},
        {p1_acme,generate_csr,2,
            [{file,
                 "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
             {line,770}]},
        {p1_acme,generate_csr,1,
            [{file,
                 "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
             {line,807}]},
        {p1_acme,request_certificate,2,
            [{file,
                 "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
             {line,392}]},
        {ejabberd_acme,issue_request,7,
            [{file,"/home/admin/ejabberd/src/ejabberd_acme.erl"},{line,230}]},
        {ejabberd_acme,handle_call,3,
            [{file,"/home/admin/ejabberd/src/ejabberd_acme.erl"},{line,125}]},
        {gen_server,try_handle_call,4,[{file,"gen_server.erl"},{line,2470}]}]}
** Client <0.3201.0> stacktrace
** [{gen,do_call,4,[{file,"gen.erl"},{line,262}]},
    {gen_server,call,3,[{file,"gen_server.erl"},{line,1297}]},
    {ejabberd_acme,request_certificate,1,
                   [{file,"/home/admin/ejabberd/src/ejabberd_acme.erl"},
                    {line,492}]},
    {ejabberd_ctl,call_command,4,
                  [{file,"/home/admin/ejabberd/src/ejabberd_ctl.erl"},
                   {line,358}]},
    {ejabberd_ctl,try_call_command,4,
                  [{file,"/home/admin/ejabberd/src/ejabberd_ctl.erl"},
                   {line,319}]},
    {ejabberd_ctl,process2,4,
                  [{file,"/home/admin/ejabberd/src/ejabberd_ctl.erl"},
                   {line,259}]},
    {ejabberd_ctl,process,2,
                  [{file,"/home/admin/ejabberd/src/ejabberd_ctl.erl"},
                   {line,237}]},
    {erpc,execute_call,4,[{file,"erpc.erl"},{line,1262}]}]

2025-06-04 10:17:37.550900+02:00 [error] CRASH REPORT:
  crasher:
    initial call: ejabberd_acme:init/1
    pid: <0.1693.0>
    registered_name: ejabberd_acme
    exception error: no function clause matching 
                     public_key:get_asn1_module('SubjectAltName') (public_key.erl:576)
      in function  public_key:der_encode/2 (public_key.erl:804)
      in call from p1_acme:generate_csr/2 (/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl:770)
      in call from p1_acme:generate_csr/1 (/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl:807)
      in call from p1_acme:request_certificate/2 (/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl:392)
      in call from ejabberd_acme:issue_request/7 (/home/admin/ejabberd/src/ejabberd_acme.erl:230)
      in call from ejabberd_acme:handle_call/3 (/home/admin/ejabberd/src/ejabberd_acme.erl:125)
      in call from gen_server:try_handle_call/4 (gen_server.erl:2470)
    ancestors: [ejabberd_sup,<0.1332.0>]
    message_queue_len: 0
    messages: []
    links: [<0.1561.0>]
    dictionary: [{yconf_ctx,[]}]
    trap_exit: true
    status: running
    heap_size: 4185
    stack_size: 29
    reductions: 2969654
  neighbours:

2025-06-04 10:17:37.568383+02:00 [error] SUPERVISOR REPORT:
    supervisor: {local,ejabberd_sup}
    errorContext: child_terminated
    reason: {function_clause,
                [{public_key,get_asn1_module,
                     ['SubjectAltName'],
                     [{file,"public_key.erl"},{line,576}]},
                 {public_key,der_encode,2,
                     [{file,"public_key.erl"},{line,804}]},
                 {p1_acme,generate_csr,2,
                     [{file,
                          "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
                      {line,770}]},
                 {p1_acme,generate_csr,1,
                     [{file,
                          "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
                      {line,807}]},
                 {p1_acme,request_certificate,2,
                     [{file,
                          "/home/admin/ejabberd/_build/default/lib/p1_acme/src/p1_acme.erl"},
                      {line,392}]},
                 {ejabberd_acme,issue_request,7,
                     [{file,"/home/admin/ejabberd/src/ejabberd_acme.erl"},
                      {line,230}]},
                 {ejabberd_acme,handle_call,3,
                     [{file,"/home/admin/ejabberd/src/ejabberd_acme.erl"},
                      {line,125}]},
                 {gen_server,try_handle_call,4,
                     [{file,"gen_server.erl"},{line,2470}]}]}
    offender: [{pid,<0.1693.0>},
               {id,ejabberd_acme},
               {mfargs,{ejabberd_acme,start_link,[]}},
               {restart_type,permanent},
               {significant,false},
               {shutdown,60000},
               {child_type,worker}]

---

When using Erlang/OTP 28.0.1, the error moves to another line:

2025-07-04 12:45:06.121116+02:00 [error] ** Generic server ejabberd_acme terminating 
** Last message in was {request,[<<"temp-acme.process-one.net">>]}
** When Server state == {state}
** Reason for termination ==
** {function_clause,
       [{public_key,get_asn1_module,
            ['ExtensionRequest'],
            [{file,"public_key.erl"},{line,590}]},
        {public_key,der_encode,2,[{file,"public_key.erl"},{line,833}]},
        {p1_acme,generate_csr,2,
            [{file,
                 "/home/admin/ejabberd2801/_build/default/lib/p1_acme/src/p1_acme.erl"},
             {line,776}]},

---

This works perfectly when compiled Erlang/OTP 27.3.

---

This comment points to this source code discussion that seems relevant. An Elixir library apparently bypassed that problem in voltone/x509#90

In any case, a specific bugreport is filled in Erlang/OTP tracker: erlang/otp#10028

[badlop]

** {function_clause,
       [{public_key,get_asn1_module,
            ['ExtensionRequest'],

That was solved in Erlang/OTP 28.0.2.

---

===> Compiling src/p1_acme.erl failed
     ┌─ src/p1_acme.erl:
     │
 772 │      Attribute = #'AttributePKCS-10'{type = ?'pkcs-9-at-extensionRequest',
     │                  ╰── record 'AttributePKCS-10' undefined, did you mean Attribute?

That's solved by commit edff139.

---

Now i can compile ejabberd with recent p1_acme using Erlang/OTP 28.0.2 and 25.2. In both cases, ejabberd starts correctly and requesting ACME certificate works correctly.