From dab03e34f5973d27797b7b415558fa75691a3830 Mon Sep 17 00:00:00 2001
From: "Wladimir J. van der Laan" <laanwj@gmail.com>
Date: Fri, 3 Jun 2011 10:52:49 +0200
Subject: [PATCH] Make base58 validator explicit

---
 gui/include/bitcoinaddressvalidator.h |  5 ++++-
 gui/src/bitcoinaddressvalidator.cpp   | 26 ++++++++++++++++++++++----
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/gui/include/bitcoinaddressvalidator.h b/gui/include/bitcoinaddressvalidator.h
index c7b2eefc..73f6ea1f 100644
--- a/gui/include/bitcoinaddressvalidator.h
+++ b/gui/include/bitcoinaddressvalidator.h
@@ -3,7 +3,10 @@
 
 #include <QRegExpValidator>
 
-class BitcoinAddressValidator : public QRegExpValidator
+/* Base48 entry widget validator.
+   Corrects near-miss characters and refuses characters that are no part of base48.
+ */
+class BitcoinAddressValidator : public QValidator
 {
     Q_OBJECT
 public:
diff --git a/gui/src/bitcoinaddressvalidator.cpp b/gui/src/bitcoinaddressvalidator.cpp
index bccf4457..761a2669 100644
--- a/gui/src/bitcoinaddressvalidator.cpp
+++ b/gui/src/bitcoinaddressvalidator.cpp
@@ -1,7 +1,5 @@
 #include "bitcoinaddressvalidator.h"
 
-#include "base58.h"
-
 #include <QDebug>
 
 /* Base58 characters are:
@@ -18,12 +16,13 @@
 */
 
 BitcoinAddressValidator::BitcoinAddressValidator(QObject *parent) :
-    QRegExpValidator(QRegExp(QString("^[")+QString(pszBase58)+QString("]+")), parent)
+    QValidator(parent)
 {
 }
 
 QValidator::State BitcoinAddressValidator::validate(QString &input, int &pos) const
 {
+    /* Correction */
     for(int idx=0; idx<input.size(); ++idx)
     {
         switch(input.at(idx).unicode())
@@ -39,7 +38,26 @@ QValidator::State BitcoinAddressValidator::validate(QString &input, int &pos) co
         default:
             break;
         }
+    }
+
+    /* Validation */
+    QValidator::State state = QValidator::Acceptable;
+    for(int idx=0; idx<input.size(); ++idx)
+    {
+        int ch = input.at(idx).unicode();
 
+        if(((ch >= '0' && ch<='9') ||
+           (ch >= 'a' && ch<='z') ||
+           (ch >= 'A' && ch<='Z')) &&
+           ch != 'l' && ch != 'I' && ch != '0' && ch != 'O')
+        {
+            /* Alphanumeric and not a 'forbidden' character */
+        }
+        else
+        {
+            state = QValidator::Invalid;
+        }
     }
-    return QRegExpValidator::validate(input, pos);
+
+    return state;
 }