Gun adapter helper: fix wildcard cert issues on OTP 23

See https://bugs.erlang.org/browse/ERL-1260 for more info.

The ssl match function is basically copied from mint, except
that `:string.lowercase/1` was replaced by `:string.casefold`.
It was a TODO in mint's code, so might as well do it since we don't need
to support OTP <20.

Closes #1834
This commit is contained in:
rinpatch 2020-06-23 20:36:21 +03:00
parent 007843b75e
commit 37f1e781cb

View file

@ -39,9 +39,36 @@ defp add_scheme_opts(opts, %{scheme: "http"}), do: opts
defp add_scheme_opts(opts, %{scheme: "https"}) do
opts
|> Keyword.put(:certificates_verification, true)
|> Keyword.put(:tls_opts, log_level: :warning)
|> Keyword.put(:tls_opts,
log_level: :warning,
customize_hostname_check: [match_fun: &ssl_match_fun/2]
)
end
# ssl_match_fun is adapted from [Mint](https://github.com/elixir-mint/mint)
# Copyright 2018 Eric Meadows-Jönsson and Andrea Leopardi
# Wildcard domain handling for DNS ID entries in the subjectAltName X.509
# extension. Note that this is a subset of the wildcard patterns implemented
# by OTP when matching against the subject CN attribute, but this is the only
# wildcard usage defined by the CA/Browser Forum's Baseline Requirements, and
# therefore the only pattern used in commercially issued certificates.
defp ssl_match_fun({:dns_id, reference}, {:dNSName, [?*, ?. | presented]}) do
case domain_without_host(reference) do
'' ->
:default
domain ->
:string.casefold(domain) == :string.casefold(presented)
end
end
defp ssl_match_fun(_reference, _presented), do: :default
defp domain_without_host([]), do: []
defp domain_without_host([?. | domain]), do: domain
defp domain_without_host([_ | more]), do: domain_without_host(more)
@spec get_conn(URI.t(), keyword()) :: {:ok, keyword()} | {:error, atom()}
def get_conn(uri, opts) do
case ConnectionPool.get_conn(uri, opts) do