--- /dev/null
+<?php
+/**
+ * The MIT License
+ * Copyright (c) 2007 Andy Smith
+ */
+namespace Abraham\TwitterOAuth;
+
+/**
+ * The HMAC-SHA1 signature method uses the HMAC-SHA1 signature algorithm as defined in [RFC2104]
+ * where the Signature Base String is the text and the key is the concatenated values (each first
+ * encoded per Parameter Encoding) of the Consumer Secret and Token Secret, separated by an '&'
+ * character (ASCII code 38) even if empty.
+ * - Chapter 9.2 ("HMAC-SHA1")
+ */
+class HmacSha1 extends SignatureMethod
+{
+ /**
+ * {@inheritDoc}
+ */
+ public function getName()
+ {
+ return "HMAC-SHA1";
+ }
+
+ /**
+ * {@inheritDoc}
+ */
+ public function buildSignature(Request $request, Consumer $consumer, Token $token = null)
+ {
+ $signatureBase = $request->getSignatureBaseString();
+
+ $parts = [$consumer->secret, null !== $token ? $token->secret : ""];
+
+ $parts = Util::urlencodeRfc3986($parts);
+ $key = implode('&', $parts);
+
+ return base64_encode(hash_hmac('sha1', $signatureBase, $key, true));
+ }
+}