From 826c0723c1dbca9742f3b8b0cb6d31df21f17664 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Fri, 14 Oct 2011 17:12:34 +0200 Subject: Add support for IPv6 parsing and reconstructing the address MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Similarly, only test against the libc function on Linux, as other OS sometimes have different behaviour. Change-Id: I9b8ef9a3d660a59882396d695202865ca307e528 Reviewed-by: João Abecasis Reviewed-by: Shane Kearns --- src/corelib/io/qipaddress.cpp | 217 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 215 insertions(+), 2 deletions(-) (limited to 'src/corelib/io/qipaddress.cpp') diff --git a/src/corelib/io/qipaddress.cpp b/src/corelib/io/qipaddress.cpp index b8871fe8b9..e996c8665c 100644 --- a/src/corelib/io/qipaddress.cpp +++ b/src/corelib/io/qipaddress.cpp @@ -71,6 +71,7 @@ static bool checkedToAscii(Buffer &buffer, const QChar *begin, const QChar *end) return true; } +static bool parseIp4Internal(IPv4Address &address, const char *ptr, bool acceptLeadingZero); bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end) { Q_ASSERT(begin != end); @@ -78,10 +79,19 @@ bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end) if (!checkedToAscii(buffer, begin, end)) return false; - int dotCount = 0; - address = 0; const char *ptr = buffer.data(); + return parseIp4Internal(address, ptr, true); +} + +static bool parseIp4Internal(IPv4Address &address, const char *ptr, bool acceptLeadingZero) +{ + address = 0; + int dotCount = 0; while (dotCount < 4) { + if (!acceptLeadingZero && *ptr == '0' && + ptr[1] != '.' && ptr[1] != '\0') + return false; + const char *endptr; bool ok; quint64 ll = qstrtoull(ptr, &endptr, 0, &ok); @@ -127,5 +137,208 @@ void toString(QString &appendTo, IPv4Address address) % number(address); } +bool parseIp6(IPv6Address &address, const QChar *begin, const QChar *end) +{ + Q_ASSERT(begin != end); + Buffer buffer; + if (!checkedToAscii(buffer, begin, end)) + return false; + + const char *ptr = buffer.data(); + + // count the colons + int colonCount = 0; + int dotCount = 0; + while (*ptr) { + if (*ptr == ':') + ++colonCount; + if (*ptr == '.') + ++dotCount; + ++ptr; + } + // IPv4-in-IPv6 addresses are stricter in what they accept + if (dotCount != 0 && dotCount != 3) + return false; + + memset(address, 0, sizeof address); + if (colonCount == 2 && end - begin == 2) // "::" + return true; + + // if there's a double colon ("::"), this is how many zeroes it means + int zeroWordsToFill; + ptr = buffer.data(); + + // there are two cases where 8 colons are allowed: at the ends + // so test that before the colon-count test + if ((ptr[0] == ':' && ptr[1] == ':') || + (ptr[end - begin - 2] == ':' && ptr[end - begin - 1] == ':')) { + zeroWordsToFill = 9 - colonCount; + } else if (colonCount < 2 || colonCount > 7) { + return false; + } else { + zeroWordsToFill = 8 - colonCount; + } + if (dotCount) + --zeroWordsToFill; + + int pos = 0; + while (pos < 15) { + const char *endptr; + bool ok; + quint64 ll = qstrtoull(ptr, &endptr, 16, &ok); + quint16 x = ll; + + if (ptr == endptr) { + // empty field, we hope it's "::" + if (zeroWordsToFill < 1) + return false; + if (pos == 0 || pos == colonCount * 2) { + if (ptr[0] == '\0' || ptr[1] != ':') + return false; + ++ptr; + } + pos += zeroWordsToFill * 2; + zeroWordsToFill = 0; + ++ptr; + continue; + } + if (!ok || ll != x) + return false; + + if (*endptr == '.') { + // this could be an IPv4 address + // it's only valid in the last element + if (pos != 12) + return false; + + IPv4Address ip4; + if (!parseIp4Internal(ip4, ptr, false)) + return false; + + address[12] = ip4 >> 24; + address[13] = ip4 >> 16; + address[14] = ip4 >> 8; + address[15] = ip4; + return true; + } + + address[pos++] = x >> 8; + address[pos++] = x & 0xff; + + if (*endptr == '\0') + break; + if (*endptr != ':') + return false; + ptr = endptr + 1; + } + return pos == 16; +} + +static inline QChar toHex(uchar c) +{ + return ushort(c > 9 ? c + 'a' - 0xA : c + '0'); +} + +void toString(QString &appendTo, IPv6Address address) +{ + // the longest IPv6 address possible is: + // "1111:2222:3333:4444:5555:6666:255.255.255.255" + // however, this function never generates that. The longest it does + // generate without an IPv4 address is: + // "1111:2222:3333:4444:5555:6666:7777:8888" + // and the longest with an IPv4 address is: + // "::ffff:255.255.255.255" + static const int Ip6AddressMaxLen = sizeof "1111:2222:3333:4444:5555:6666:7777:8888"; + static const int Ip6WithIp4AddressMaxLen = sizeof "::ffff:255.255.255.255"; + + // check for the special cases + const quint64 zeroes[] = { 0, 0 }; + bool embeddedIp4 = false; + + // we consider embedded IPv4 for: + // ::ffff:x.x.x.x + // ::x.x.x.y except if the x are 0 too + if (memcmp(address, zeroes, 10) == 0) { + if (address[10] == 0xff && address[11] == 0xff) { + embeddedIp4 = true; + } else if (address[10] == 0 && address[11] == 0) { + if (address[12] != 0 || address[13] != 0 || address[14] != 0) { + embeddedIp4 = true; + } else if (address[15] == 0) { + appendTo.append(QLatin1String("::")); + return; + } + } + } + + // QString::reserve doesn't shrink, so it's fine to us + appendTo.reserve(appendTo.size() + + embeddedIp4 ? Ip6WithIp4AddressMaxLen : Ip6AddressMaxLen); + + // for finding where to place the "::" + int zeroRunLength = 0; // in octets + int zeroRunOffset = 0; // in octets + for (int i = 0; i < 16; i += 2) { + if (address[i] == 0 && address[i + 1] == 0) { + // found a zero, scan forward to see how many more there are + int j; + for (j = i; j < 16; j += 2) { + if (address[j] != 0 || address[j+1] != 0) + break; + } + + if (j - i > zeroRunLength) { + zeroRunLength = j - i; + zeroRunOffset = i; + i = j; + } + } + } + + const QChar colon = ushort(':'); + if (zeroRunLength < 4) + zeroRunOffset = -1; + else if (zeroRunOffset == 0) + appendTo.append(colon); + + for (int i = 0; i < 16; i += 2) { + if (i == zeroRunOffset) { + appendTo.append(colon); + i += zeroRunLength - 2; + continue; + } + + if (i == 12 && embeddedIp4) { + IPv4Address ip4 = address[12] << 24 | + address[13] << 16 | + address[14] << 8 | + address[15]; + toString(appendTo, ip4); + return; + } + + if (address[i]) { + if (address[i] >> 4) { + appendTo.append(toHex(address[i] >> 4)); + appendTo.append(toHex(address[i] & 0xf)); + appendTo.append(toHex(address[i + 1] >> 4)); + appendTo.append(toHex(address[i + 1] & 0xf)); + } else if (address[i] & 0xf) { + appendTo.append(toHex(address[i] & 0xf)); + appendTo.append(toHex(address[i + 1] >> 4)); + appendTo.append(toHex(address[i + 1] & 0xf)); + } + } else if (address[i + 1] >> 4) { + appendTo.append(toHex(address[i + 1] >> 4)); + appendTo.append(toHex(address[i + 1] & 0xf)); + } else { + appendTo.append(toHex(address[i + 1] & 0xf)); + } + + if (i != 14) + appendTo.append(colon); + } +} + } QT_END_NAMESPACE -- cgit v1.2.3