1 files changed, 30 insertions, 0 deletions
diff --git a/deps/oauth/src/oauth_rsa_sha1.erl b/deps/oauth/src/oauth_rsa_sha1.erl
new file mode 100644
index 00000000..6f4828e0
--- /dev/null
+++ b/deps/oauth/src/oauth_rsa_sha1.erl
@@ -0,0 +1,30 @@
+-module(oauth_rsa_sha1).
+
+-export([signature/2, verify/3]).
+
+-include_lib("public_key/include/public_key.hrl").
+
+
+signature(BaseString, PrivateKeyPath) ->
+  {ok, [Info]} = public_key:pem_to_der(PrivateKeyPath),
+  {ok, PrivateKey} = public_key:decode_private_key(Info),
+  base64:encode_to_string(public_key:sign(list_to_binary(BaseString), PrivateKey)).
+
+verify(Signature, BaseString, PublicKey) ->
+  public_key:verify_signature(to_binary(BaseString), sha, base64:decode(Signature), public_key(PublicKey)).
+
+to_binary(Term) when is_list(Term) ->
+  list_to_binary(Term);
+to_binary(Term) when is_binary(Term) ->
+  Term.
+
+public_key(Path) when is_list(Path) ->
+  {ok, [{cert, DerCert, not_encrypted}]} = public_key:pem_to_der(Path),
+  {ok, Cert} = public_key:pkix_decode_cert(DerCert, otp),
+  public_key(Cert);
+public_key(#'OTPCertificate'{tbsCertificate=Cert}) ->
+  public_key(Cert);
+public_key(#'OTPTBSCertificate'{subjectPublicKeyInfo=Info}) ->
+  public_key(Info);
+public_key(#'OTPSubjectPublicKeyInfo'{subjectPublicKey=Key}) ->
+  Key.