From 90dadf57cd0bf3b56535e4290583abcb2fca00e0 Mon Sep 17 00:00:00 2001
From: Christian Hohnstaedt <christian@hohnstaedt.de>
Date: Wed, 8 Jun 2011 06:19:16 +0200
Subject: [PATCH] Fix IPv6 address handling in v3 extensions

---
 lib/x509v3ext.cpp | 53 +++++++++++++++++++++++++++++++++--------------
 widgets/v3ext.cpp | 32 +++++++++++++++++++++++++++-
 2 files changed, 68 insertions(+), 17 deletions(-)

diff --git a/lib/x509v3ext.cpp b/lib/x509v3ext.cpp
index 95cc37af..177d4296 100644
--- a/lib/x509v3ext.cpp
+++ b/lib/x509v3ext.cpp
@@ -196,6 +196,42 @@ static bool asn1TypePrintable(int type)
 	return false;
 }
 
+static QString ipv6_from_binary(const unsigned char *p)
+{
+	QString ip;
+	int i, skip =0, skiplen = 0, skippos =0;
+
+	/* find largest gap */
+	for (i = 0; i < 17; i += 2) {
+		if (i==16 || (p[i] | p[i +1])) {
+			if (skiplen < skip) {
+				skiplen = skip;
+				skippos = i - skip;
+			}
+			skip = 0;
+		} else {
+			skip += 2;
+		}
+	}
+	for (i = 0, skip = 0; i < 16; i += 2) {
+		int x = p[i] << 8 | p[i+1];
+		skip += skippos == i;
+		switch (!x*4 + skip) {
+		case 5: // skip first 0
+			skip = 2;
+			ip += ":";
+		case 6: // skip next 0
+			break;
+		default: // no reduction
+			skip = 0;
+			ip += QString("%1%2").arg(i? ":" : "").arg(x,0,16);
+		}
+	}
+	if (skip == 2)
+		ip += ":";
+	return ip;
+}
+
 static bool
 genName2conf(GENERAL_NAME *gen, QString tag, QString *single, QString *sect)
 {
@@ -222,22 +258,7 @@ genName2conf(GENERAL_NAME *gen, QString tag, QString *single, QString *sect)
 				arg(p[0]).arg(p[1]).arg(p[2]).arg(p[3]);
 			return true;
 		} else if(gen->d.ip->length == 16) {
-			int skip = 0;
-			*single = "IP";
-			for (int i = 0; i < 8; i++, p+=2) {
-				int x = p[0] << 8 | p[1];
-				switch (!x*4 + skip) {
-				case 4: // start reduction
-					*single += QString(":");
-					skip = 1;
-				case 5: // skip repeated 0
-					break;
-				case 1: // end of reduction
-					skip = 2;
-				default:
-					*single += QString(":%1").arg(x,0,16);
-				}
-			}
+			*single = "IP:" + ipv6_from_binary(gen->d.ip->data);
 			return true;
 		}
 		return false;
diff --git a/widgets/v3ext.cpp b/widgets/v3ext.cpp
index e16a1dd8..a94ef18e 100644
--- a/widgets/v3ext.cpp
+++ b/widgets/v3ext.cpp
@@ -16,6 +16,36 @@
 #include "MainWindow.h"
 #include "lib/exception.h"
 
+
+//	Complex regular expressions.
+
+#define BYTE_DEC	"(?:25[0-5]|2[0-4]\\d|1\\d\\d|\\d{1,2})"
+#define IPV4_ADDR	"(?:(?:" BYTE_DEC "\\.){3}" BYTE_DEC ")"
+#define SHORT_HEX	"[0-9a-fA-F]{1,4}"
+#define IPV6_FORM0	"(?:(?:" SHORT_HEX ":){7}" SHORT_HEX ")"
+#define IPV6_FORM1	"(?::(?::" SHORT_HEX "){1,7})"
+#define IPV6_FORM2	"(?:" SHORT_HEX ":(?::" SHORT_HEX "){1,6})"
+#define IPV6_FORM3	"(?:(?:" SHORT_HEX ":){2}(?::" SHORT_HEX "){1,5})"
+#define IPV6_FORM4	"(?:(?:" SHORT_HEX ":){3}(?::" SHORT_HEX "){1,4})"
+#define IPV6_FORM5	"(?:(?:" SHORT_HEX ":){4}(?::" SHORT_HEX "){1,3})"
+#define IPV6_FORM6	"(?:(?:" SHORT_HEX ":){5}(?::" SHORT_HEX "){1,2})"
+#define IPV6_FORM7	"(?:(?:" SHORT_HEX ":){6}:" SHORT_HEX ")"
+#define IPV6_FORM8	"(?:(?:" SHORT_HEX ":){7}:)"
+#define IPV6_FORM9	"(?:::)"
+#define IPV6_V4_0	"(?:(?:" SHORT_HEX ":){6}" IPV4_ADDR ")"
+#define IPV6_V4_1	"(?::(?::" SHORT_HEX "){0,5}:" IPV4_ADDR ")"
+#define IPV6_V4_2	"(?:" SHORT_HEX ":(?::" SHORT_HEX "){0,4}:" IPV4_ADDR ")"
+#define IPV6_V4_3	"(?:(?:" SHORT_HEX ":){2}(?::" SHORT_HEX "){0,3}:" IPV4_ADDR ")"
+#define IPV6_V4_4	"(?:(?:" SHORT_HEX ":){3}(?::" SHORT_HEX "){0,2}:" IPV4_ADDR ")"
+#define IPV6_V4_5	"(?:(?:" SHORT_HEX ":){4}(?::" SHORT_HEX ")?:" IPV4_ADDR ")"
+#define IPV6_V4_6	"(?:(?:" SHORT_HEX ":){5}:" IPV4_ADDR ")"
+#define IPV6_ADDR	"(?:" IPV6_FORM0 "|" IPV6_FORM1 "|" IPV6_FORM2 "|"	\
+						IPV6_FORM3 "|" IPV6_FORM4 "|" IPV6_FORM5 "|"	\
+						IPV6_FORM6 "|" IPV6_FORM7 "|" IPV6_FORM8 "|"	\
+						IPV6_FORM9 "|" IPV6_V4_0 "|" IPV6_V4_1 "|"		\
+						IPV6_V4_2 "|" IPV6_V4_3 "|" IPV6_V4_4 "|"		\
+						IPV6_V4_5 "|" IPV6_V4_6 ")"
+
 v3ext::v3ext(QWidget *parent)
 	:QDialog(parent)
 {
@@ -74,7 +104,7 @@ void v3ext::setupLineEdit(const QString &s, QLineEdit *l)
 		tt = tr("a DNS domain name");
 	} else if (s == "IP") {
 		tt = tr("an IP address");
-		QRegExp rx("[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}");
+		QRegExp rx(IPV4_ADDR "|" IPV6_ADDR);
 		v = new QRegExpValidator(rx, this);
 	} else if (s == "otherName") {
 		tt = tr("Syntax: <OID>;TYPE:text like '1.2.3.4:UTF8:name'");