basic diaspora encryption

1 files changed, 90 insertions, 0 deletions

diff --git a/include/diaspora.php b/include/diaspora.php
new file mode 100644
index 000000000..eedcad719
--- /dev/null
+++ b/include/diaspora.php
@@ -0,0 +1,90 @@
+<?php
+
+
+
+
+function diaspora_base_message($type,$data) {
+
+	$tpl = get_markup_template('diaspora_' . $type . '.tpl');
+	if(! $tpl) 
+		return '';
+	return replace_macros($tpl,$data);
+
+}
+
+
+function diaspora_msg_build($msg,$user,$contact,$prvkey,$pubkey) {
+	$a = get_app();
+
+	$inner_aes_key = random_string(16);
+	$b_inner_aes_key = base64_encode($inner_aes_key);
+	$inner_iv = random_string(16);
+	$b_inner_iv = base64_encode($inner_iv);
+
+	$outer_aes_key = random_string(16);
+	$b_outer_aes_key = base64_encode($outer_aes_key);
+	$outer_iv = random_string(16);
+	$b_outer_iv = base64_encode($outer_iv);
+	
+	$handle = 'acct:' . $user['nickname'] . '@' . substr($a->get_baseurl(), strpos('://') + 3);
+
+	$padded_data = pkcs5_pad($msg);
+	$inner_encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $inner_aes_key, $padded_data, MCRYPT_MODE_CBC, $inner_iv);
+
+	$b64_data = base64_encode($inner_encrypted);
+	$b64url_data = base64url_encode($b64_data);
+	$b64url_stripped = str_replace(array("\n","\r"," ","\t"),array('','','',''),$b64url_data);
+    $lines = str_split($b64url_stripped,60);
+    $data = implode("\n",$lines);
+	$data = $data . (($data[-1] != "\n") ? "\n" : '') ;
+	$type = 'application/atom+xml';
+	$encoding = 'base64url';
+	$alg = 'RSA-SHA256';
+
+	$signable_data = $data  . '.' . base64url_encode($type) . "\n" . '.' 
+		. base64url_encode($encoding) . "\n" . '.' . base64url_encode($alg) . "\n";
+
+	$signature = '';
+	$result = openssl_sign($signable_data,$signature,$prvkey,'SHA256');
+
+	$sig = base64url_encode($signature);
+
+$decrypted_header = <<< EOT
+<decrypted_header>
+  <iv>$b_inner_iv</iv>
+  <aes_key>$b_inner_aes_key</aes_key>
+  <author>
+    <name>{$contact['name']}</name>
+    <uri>$handle</uri>
+  </author>
+</decrypted_header>
+EOT;
+
+	$decrypted_header = pkcs5_pad($decrypted_header);
+	$ciphertext = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $outer_aes_key, $decrypted_header, MCRYPT_MODE_CBC, $outer_iv);
+
+	$outer_json = json_encode(array('iv' => $b64_outer_iv,'key' => $b64_outer_aes_key));
+	$encrypted_outer_key_bundle = '';
+	openssl_public_encrypt($outer_json,$encrypted_outer_key_bundle,$pubkey);
+	
+	$b64_encrypted_outer_key_bundle = base64_encode($encrypted_outer_key_bundle);
+	$encrypted_header_json_object = json_encode(array('aes_key' => base64_encode($encrypted_outer_key_bundle), 
+		'ciphertext' => base64_encode($ciphertext)));
+	$encrypted_header = '<encrypted_header>' . base64_encode($encrypted_header_json_object) . '</encrypted_header>';
+
+$magicenv = <<< EOT
+<?xml version='1.0' encoding='UTF-8'?>
+<entry xmlns='http://www.w3.org/2005/Atom'>
+  $encrypted_header
+  <me:env xmlns:me="http://salmon-protocol.org/ns/magic-env">
+    <me:encoding>base64url</me:encoding>
+    <me:alg>RSA-SHA256</me:alg>
+    <me:data type="application/atom+xml">$data</me:data>
+    <me:sig>$sig</me:sig>
+  </me:env>
+</entry>
+EOT;
+
+	return $magic_env;
+
+}
\ No newline at end of file