Ejabberd mod_ecaptcha crash

Question

I'm trying to install new mod_ecaptcha mod in ejabberd-contrib. But ejabberd crashed after enabling it. My initial data: ejabberd 23.01 erlang 25.2.3

1. I have enabled ejabberd-contrib by ejabberdctl modules_update_specs

2. Installed and recompiled mod_ecaptcha

   ejabberdctl module_install mod_ecaptcha make -C .ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/deps/ecaptcha/c_src ejabberdctl module_upgrade mod_ecaptcha It's compiled without errors.

3. Installed erlang-dev apt install erlang-dev because without it it wasn't compiled

4. I'm using basic config

captcha_cmd: mod_ecaptcha
captcha_url: http://myjabber:5280/captcha
listen:
  -
    port: 5280
    module: ejabberd_http
    request_handlers:
      /captcha: ejabberd_captcha
modules:
  mod_ecaptcha: {}

In final I started my ejabberd and receive errors in error.log and ejabberd service crashes.

2023-06-19 19:59:11.892726+03:00 [error] <0.757.0>@proc_lib:crash_report/4:539 CRASH REPORT: crasher: initial call: ejabberd_captcha:init/1 pid: <0.757.0> registered_name: [] exception error: undefined function ecaptcha_nif:rand_size/0 in function ecaptcha:pixels/2 (/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/deps/ecaptcha/src/ecaptcha.erl, line 63) in call from ecaptcha:img/3 (/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/deps/ecaptcha/src/ecaptcha.erl, line 107) in call from mod_ecaptcha:create_image/1 (/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/src/mod_ecaptcha.erl, line 78) in call from ejabberd_captcha:check_captcha_setup/0 (ejabberd_captcha.erl, line 573) in call from ejabberd_captcha:init/1 (ejabberd_captcha.erl, line 294) in call from gen_server:init_it/2 (gen_server.erl, line 851) in call from gen_server:init_it/6 (gen_server.erl, line 814) ancestors: [ejabberd_sup,<0.123.0>] message_queue_len: 0 messages: [] links: [<0.412.0>] dictionary: [{rand_seed,{#{bits => 58,jump => #Fun<rand.3.34006561>, next => #Fun<rand.0.34006561>,type => exsss, uniform => #Fun<rand.1.34006561>, uniform_n => #Fun<rand.2.34006561>}, [114826259057369191|191927986778231166]}}] trap_exit: false status: running heap_size: 376 stack_size: 28 reductions: 393 neighbours: 2023-06-19 19:59:11.925067+03:00 [critical] <0.123.0>@ejabberd_app:start/2:68 Failed to start ejabberd application: {error, {shutdown, {failed_to_start_child, ejabberd_captcha, {undef, [{ecaptcha_nif,rand_size,[],[]}, {ecaptcha,pixels,2, [{file, "/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/deps/ecaptcha/src/ecaptcha.erl"}, {line,63}]}, {ecaptcha,img,3, [{file, "/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/deps/ecaptcha/src/ecaptcha.erl"}, {line,107}]}, {mod_ecaptcha,create_image,1, [{file, "/var/lib/ejabberd/.ejabberd-modules/sources/ejabberd-contrib/mod_ecaptcha/src/mod_ecaptcha.erl"}, {line,78}]}, {ejabberd_captcha, check_captcha_setup,0, [{file,"ejabberd_captcha.erl"}, {line,573}]}, {ejabberd_captcha,init,1, [{file,"ejabberd_captcha.erl"}, {line,294}]}, {gen_server,init_it,2, [{file,"gen_server.erl"}, {line,851}]}, {gen_server,init_it,6, [{file,"gen_server.erl"}, {line,814}]}]}}}}

Full logs:

Error.log https://pastebin.com/yQKefm4N

Ejabberd.log https://pastebin.com/uENVE5fC

Can you help me please?

Answer 1

undefined function ecaptcha_nif:rand_size/0

It seems some file was not compiled, maybe ecaptcha_nif.beam or ecaptcha.so Or they weren't installed, or they cannot be loaded.

There is a commit that improves this in ejabberd 23.04: https://github.com/processone/ejabberd/commit/c5c7e7fc4db97022986d1595b73781571a3d59f2

First of all, check that all the source code files were compiled and installed:

$ find .ejabberd-modules/mod_ecaptcha/
.ejabberd-modules/mod_ecaptcha/
.ejabberd-modules/mod_ecaptcha/COMMIT.json
.ejabberd-modules/mod_ecaptcha/conf
.ejabberd-modules/mod_ecaptcha/conf/mod_ecaptcha.yml
.ejabberd-modules/mod_ecaptcha/ebin
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha_gif_lzw.beam
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha.beam
.ejabberd-modules/mod_ecaptcha/ebin/mod_ecaptcha.beam
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha_color.beam
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha_nif.beam
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha_gif.beam
.ejabberd-modules/mod_ecaptcha/ebin/ecaptcha_png.beam
.ejabberd-modules/mod_ecaptcha/mod_ecaptcha.spec
.ejabberd-modules/mod_ecaptcha/priv
.ejabberd-modules/mod_ecaptcha/priv/ecaptcha.so

Are all the files there? Specially ecaptcha_nif.beam and ecaptcha.so

If some file is missing, maybe you need to install the gcc compiler, or some other package to let ecaptcha.so get compiled.

If all the files are there, maybe ejabberd 23.01 is not able to load them.

The obvious solution would be to update update ejabberd to 23.04.

If you cannot update ejabberd 23.01 to 23.04 right now, another solution is that you copy ecaptcha.so to a place where ejabberd 23.01 can find it. For example, search for a file called xmpp_uri.so, and copy ecaptcha.so in the same directory.