Fix use-after-free bug, and better error handling

README.txt

@@ -1,25 +1,16 @@
 Code implementing a simple payment protocol for Bitcoin (PaymentRequest/etc).
 
-See https://gist.github.com/4120476
+See https://en.bitcoin.it/wiki/BIP_0070
 
-Dependencies:
-  OpenSSL (library and openssl command-line tool)
-  Google Protocol Buffers (library and protoc command-line compiler)
+Files here:
 
-Debian/Ubuntu:
-  apt-get install openssl protobuf
-OSX MacPorts:
-  port install openssl protobuf
+paymentrequest.proto : Google protocol buffer definition of messages
 
-To compile:
-  make
+Subdirectories here:
 
-The Makefile will create a "certificate authority in a box" in ca_in_a_box/ and
-compile command-line tools:
+c++ : command-line utilities for creating/validating PaymentRequests
 
-paymentrequest-create  # Prototype code: create a PaymentRequest message
-paymentrequest-verify  # Prototype code: verify a PaymentRequest message
+php : php code and a demo website for creating/validating PaymentRequests
 
-
-Example usage:
-  paymentrequest-create paytoaddress=1BTCorgHwCg6u2YSAWKgS17qUad6kHmtQW memo="Just Testing" amount=11.0 | paymentrequest-dump
+ca_in_a_box : "certificate authority in a box", used to generate
+  certificates and certificate chains for testing.

c++/README.txt

@@ -0,0 +1,21 @@
+Dependencies:
+  OpenSSL (library and openssl command-line tool)
+  Google Protocol Buffers (library and protoc command-line compiler)
+
+Debian/Ubuntu:
+  apt-get install openssl protobuf
+OSX MacPorts:
+  port install openssl protobuf
+
+To compile:
+  make
+
+The Makefile will create a "certificate authority in a box" in ../ca_in_a_box/ and
+compile command-line tools:
+
+paymentrequest-create  # Prototype code: create a PaymentRequest message
+paymentrequest-verify  # Prototype code: verify a PaymentRequest message
+
+
+Example usage:
+  paymentrequest-create paytoaddress=1BTCorgHwCg6u2YSAWKgS17qUad6kHmtQW memo="Just Testing" amount=11.0 | paymentrequest-dump

c++/paymentrequest-create.cpp

@@ -37,7 +37,7 @@
 #include <openssl/x509_vfy.h>
 #include <openssl/evp.h>
 
-#include "paymentrequest.pb.h";
+#include "paymentrequest.pb.h"
 #include <google/protobuf/io/tokenizer.h>  // For string-to-uint64 conversion
 #include "util.h"
 
@@ -352,25 +352,28 @@ int main(int argc, char **argv) {
 
     // Certificate chain:
     X509Certificates certChain;
-    X509 *first_cert = NULL;
-    X509 *last_cert = NULL;
-    EVP_PKEY *pubkey = NULL;
     std::list<string> certFiles = split(params["certificates"], ",");
+    std::vector<X509*> certs;
     for (std::list<string>::iterator it = certFiles.begin(); it != certFiles.end(); it++) {
         X509 *cert = parse_pem_cert(load_file(*it));
-        certChain.add_certificate(x509_to_der(cert));
-        if (first_cert == NULL) {
-            first_cert = cert; // Don't free this yet, need pubkey to stay valid
-            pubkey = X509_get_pubkey(cert);
-        }
-        else {
-            X509_free(cert);
+        if (cert == NULL) {
+            fprintf(stderr, "Could not read %s\n", it->c_str());
+            continue;
         }
-        last_cert = cert;
+        certs.push_back(cert);
+        certChain.add_certificate(x509_to_der(cert));
+    }
+
+    if (certs.empty()) {
+        fprintf(stderr, "Could not load any certificates\n");
+        exit(1);
     }
 
+    // Public key is first certificate:
+    EVP_PKEY *pubkey = X509_get_pubkey(certs.front());
+
     // Fetch any missing intermediate certificates, if we can:
-    fetchParentCerts(certChain, last_cert);
+    fetchParentCerts(certChain, certs.back());
 
     string certChainBytes;
     certChain.SerializeToString(&certChainBytes);
@@ -410,7 +413,10 @@ int main(int argc, char **argv) {
     }
     EVP_MD_CTX_destroy(ctx);
     EVP_PKEY_free(pubkey);
-    X509_free(first_cert);
+    for (std::vector<X509*>::iterator it = certs.begin(); it != certs.end(); it++) {
+        X509_free(*it);
+    }
+    certs.clear();
 
     // We got here, so the signature is self-consistent.
     request.set_signature(signature, actual_signature_len);

c++/paymentrequest-dump.cpp

@@ -15,7 +15,7 @@
 #include <openssl/x509.h>
 #include <openssl/x509_vfy.h>
 
-#include "paymentrequest.pb.h";
+#include "paymentrequest.pb.h"
 #include "util.h"
 
 using std::string;

php/demo_website/createpaymentrequest.php

@@ -66,7 +66,7 @@ function createPaymentRequest($params)
         if (!empty($params[$field])) {
             $output = new \payments\Output();
             $r = address_to_script($params["address".$i]);
-            if ($r[0]) $testnet = true;
+            $testnet = $r[0];
             $output->setScript($r[1]);
 	    $output->setAmount($params["amount".$i]*1.0e8);
 	    $totalAmount += $params["amount".$i];
@@ -183,6 +183,11 @@ function createPaymentRequest($params)
 $validationData['amount3'] = array('type' => 'btcamount');
 
 if (isset($request['submit'])) {
+    // For debugging Tor connections: replace $CLIENT_IP
+    // in memo/ACK_message with client's IP address:
+    $request['memo'] = str_replace('$CLIENT_IP', $_SERVER['REMOTE_ADDR'], $request['memo']);
+    $request['ACK_message'] = str_replace('$CLIENT_IP', $_SERVER['REMOTE_ADDR'], $request['ACK_message']);
+
     $formErrors = validateForm($request, $validationData);
 
     if (count($formErrors) == 0) {