Make QIPAddress::parseIp6 return the first bad character

In case of undetermined error, returns end.

Change-Id: Ic5d16bab5fc56ad24f19da25f73f9b844ce11d3f
Reviewed-by: David Faure (KDE) <faure@kde.org>

4 files changed, 40 insertions, 27 deletions

diff --git a/src/corelib/io/qipaddress.cpp b/src/corelib/io/qipaddress.cpp
index bd36d36ac1..334c239c91 100644
--- a/src/corelib/io/qipaddress.cpp
+++ b/src/corelib/io/qipaddress.cpp
@@ -53,7 +53,7 @@ static QString number(quint8 val, int base = 10)
 }
 
 typedef QVarLengthArray<char, 64> Buffer;
-static bool checkedToAscii(Buffer &buffer, const QChar *begin, const QChar *end)
+static const QChar *checkedToAscii(Buffer &buffer, const QChar *begin, const QChar *end)
 {
     const ushort *const ubegin = reinterpret_cast<const ushort *>(begin);
     const ushort *const uend = reinterpret_cast<const ushort *>(end);
@@ -64,11 +64,11 @@ static bool checkedToAscii(Buffer &buffer, const QChar *begin, const QChar *end)
 
     while (src != uend) {
         if (*src >= 0x7f)
-            return false;
+            return reinterpret_cast<const QChar *>(src);
         *dst++ = *src++;
     }
     *dst = '\0';
-    return true;
+    return 0;
 }
 
 static bool parseIp4Internal(IPv4Address &address, const char *ptr, bool acceptLeadingZero);
@@ -76,7 +76,7 @@ bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end)
 {
     Q_ASSERT(begin != end);
     Buffer buffer;
-    if (!checkedToAscii(buffer, begin, end))
+    if (checkedToAscii(buffer, begin, end))
         return false;
 
     const char *ptr = buffer.data();
@@ -137,12 +137,23 @@ void toString(QString &appendTo, IPv4Address address)
                 % number(address);
 }
 
-bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
+/*!
+    \internal
+    \since 5.0
+
+    Parses one IPv6 address from \a begin to \a end and stores the
+    representation in \a address. Returns null if everything was parsed
+    correctly, or the pointer to the first bad character where parsing failed.
+    If the parsing failed for a reason not related to a particular character,
+    returns \a end.
+*/
+const QChar *parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
 {
     Q_ASSERT(begin != end);
     Buffer buffer;
-    if (!checkedToAscii(buffer, begin, end))
-        return false;
+    const QChar *ret = checkedToAscii(buffer, begin, end);
+    if (ret)
+        return ret;
 
     const char *ptr = buffer.data();
 
@@ -158,11 +169,11 @@ bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
     }
     // IPv4-in-IPv6 addresses are stricter in what they accept
     if (dotCount != 0 && dotCount != 3)
-        return false;
+        return end;
 
     memset(address, 0, sizeof address);
     if (colonCount == 2 && end - begin == 2) // "::"
-        return true;
+        return 0;
 
     // if there's a double colon ("::"), this is how many zeroes it means
     int zeroWordsToFill;
@@ -174,7 +185,7 @@ bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
             (ptr[end - begin - 2] == ':' && ptr[end - begin - 1] == ':')) {
         zeroWordsToFill = 9 - colonCount;
     } else if (colonCount < 2 || colonCount > 7) {
-        return false;
+        return end;
     } else {
         zeroWordsToFill = 8 - colonCount;
     }
@@ -183,18 +194,13 @@ bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
 
     int pos = 0;
     while (pos < 15) {
-        const char *endptr;
-        bool ok;
-        quint64 ll = qstrtoull(ptr, &endptr, 16, &ok);
-        quint16 x = ll;
-
-        if (ptr == endptr) {
+        if (*ptr == ':') {
             // empty field, we hope it's "::"
             if (zeroWordsToFill < 1)
-                return false;
+                return begin + (ptr - buffer.data());
             if (pos == 0 || pos == colonCount * 2) {
                 if (ptr[0] == '\0' || ptr[1] != ':')
-                    return false;
+                    return begin + (ptr - buffer.data());
                 ++ptr;
             }
             pos += zeroWordsToFill * 2;
@@ -202,24 +208,30 @@ bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
             ++ptr;
             continue;
         }
+
+        const char *endptr;
+        bool ok;
+        quint64 ll = qstrtoull(ptr, &endptr, 16, &ok);
+        quint16 x = ll;
+
         if (!ok || ll != x)
-            return false;
+            return begin + (ptr - buffer.data());
 
         if (*endptr == '.') {
             // this could be an IPv4 address
             // it's only valid in the last element
             if (pos != 12)
-                return false;
+                return begin + (ptr - buffer.data());
 
             IPv4Address ip4;
             if (!parseIp4Internal(ip4, ptr, false))
-                return false;
+                return begin + (ptr - buffer.data());
 
             address[12] = ip4 >> 24;
             address[13] = ip4 >> 16;
             address[14] = ip4 >> 8;
             address[15] = ip4;
-            return true;
+            return 0;
         }
 
         address[pos++] = x >> 8;
@@ -228,10 +240,10 @@ bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end)
         if (*endptr == '\0')
             break;
         if (*endptr != ':')
-            return false;
+            return begin + (endptr - buffer.data());
         ptr = endptr + 1;
     }
-    return pos == 16;
+    return pos == 16 ? 0 : end;
 }
 
 static inline QChar toHex(uchar c)
diff --git a/src/corelib/io/qipaddress_p.h b/src/corelib/io/qipaddress_p.h
index d5c158d4d1..3059a1c205 100644
--- a/src/corelib/io/qipaddress_p.h
+++ b/src/corelib/io/qipaddress_p.h
@@ -63,7 +63,7 @@ typedef quint32 IPv4Address;
 typedef quint8 IPv6Address[16];
 
 Q_CORE_EXPORT bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end);
-Q_CORE_EXPORT bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end);
+Q_CORE_EXPORT const QChar *parseIp6(IPv6Address &address, const QChar *begin, const QChar *end);
 Q_CORE_EXPORT void toString(QString &appendTo, IPv4Address address);
 Q_CORE_EXPORT void toString(QString &appendTo, IPv6Address address);
 
diff --git a/src/corelib/io/qurl.cpp b/src/corelib/io/qurl.cpp
index 30320c9cc2..d7729b7cb9 100644
--- a/src/corelib/io/qurl.cpp
+++ b/src/corelib/io/qurl.cpp
@@ -1141,7 +1141,8 @@ static const QChar *parseIpFuture(QString &host, const QChar *begin, const QChar
 static bool parseIp6(QString &host, const QChar *begin, const QChar *end, QUrl::ParsingMode mode)
 {
     QIPAddressUtils::IPv6Address address;
-    if (!QIPAddressUtils::parseIp6(address, begin, end)) {
+    const QChar *ret = QIPAddressUtils::parseIp6(address, begin, end);
+    if (ret) {
         // this struct is kept in automatic storage because it's only 4 bytes
         const ushort decodeColon[] = { decode(':'), 0 };
 
diff --git a/src/network/kernel/qhostaddress.cpp b/src/network/kernel/qhostaddress.cpp
index dc67b0d835..5ef428305c 100644
--- a/src/network/kernel/qhostaddress.cpp
+++ b/src/network/kernel/qhostaddress.cpp
@@ -189,7 +189,7 @@ static bool parseIp6(const QString &address, QIPAddressUtils::IPv6Address &addr,
     } else {
         scopeId->clear();
     }
-    return QIPAddressUtils::parseIp6(addr, tmp.constBegin(), tmp.constEnd());
+    return QIPAddressUtils::parseIp6(addr, tmp.constBegin(), tmp.constEnd()) == 0;
 }
 
 bool QHostAddressPrivate::parse()