//
// Parse
//
// Convert this IPv4 address into a sequence of 4 8-bit numbers
//
unsafe private static bool Parse(string name, byte *numbers, int start, int end)
{
fixed(char *ipString = name)
{
int changedEnd = end;
long result = IPv4AddressHelper.ParseNonCanonical(ipString, start, ref changedEnd, true);
// end includes ports, so changedEnd may be different from end
Debug.Assert(result != Invalid, "Failed to parse after already validated: " + name);
numbers[0] = (byte)(result >> 24);
numbers[1] = (byte)(result >> 16);
numbers[2] = (byte)(result >> 8);
numbers[3] = (byte)(result);
}
return(numbers[0] == 127);
}
//
// InternalIsValid
//
// Determine whether a name is a valid IPv6 address. Rules are:
//
// * 8 groups of 16-bit hex numbers, separated by ':'
// * a *single* run of zeros can be compressed using the symbol '::'
// * an optional string of a ScopeID delimited by '%'
// * an optional (last) 1 or 2 character prefix length field delimited by '/'
// * the last 32 bits in an address can be represented as an IPv4 address
//
// Inputs:
// <argument> name
// Domain name field of a URI to check for pattern match with
// IPv6 address
// validateStrictAddress: if set to true, it expects strict ipv6 address. Otherwise it expects
// part of the string in ipv6 format.
//
// Outputs:
// Nothing
//
// Assumes:
// the correct name is terminated by ']' character
//
// Returns:
// true if <name> has IPv6 format/ipv6 address based on validateStrictAddress, else false
//
// Throws:
// Nothing
//
// Remarks: MUST NOT be used unless all input indexes are verified and trusted.
// start must be next to '[' position, or error is reported
private static unsafe bool InternalIsValid(char *name, int start, ref int end, bool validateStrictAddress)
{
int sequenceCount = 0;
int sequenceLength = 0;
bool haveCompressor = false;
bool haveIPv4Address = false;
bool havePrefix = false;
bool expectingNumber = true;
int lastSequence = 1;
// Starting with a colon character is only valid if another colon follows.
if (name[start] == ':' && (start + 1 >= end || name[start + 1] != ':'))
{
return(false);
}
int i;
for (i = start; i < end; ++i)
{
if (havePrefix ? (name[i] >= '0' && name[i] <= '9') : Uri.IsHexDigit(name[i]))
{
++sequenceLength;
expectingNumber = false;
}
else
{
if (sequenceLength > 4)
{
return(false);
}
if (sequenceLength != 0)
{
++sequenceCount;
lastSequence = i - sequenceLength;
}
switch (name[i])
{
case '%':
while (true)
{
//accept anything in scopeID
if (++i == end)
{
// no closing ']', fail
return(false);
}
if (name[i] == ']')
{
goto case ']';
}
else if (name[i] == '/')
{
goto case '/';
}
}
case ']':
start = i;
i = end;
//this will make i = end+1
continue;
case ':':
if ((i > 0) && (name[i - 1] == ':'))
{
if (haveCompressor)
{
//
// can only have one per IPv6 address
//
return(false);
}
haveCompressor = true;
expectingNumber = false;
}
else
{
expectingNumber = true;
}
break;
case '/':
if (validateStrictAddress)
{
return(false);
}
if ((sequenceCount == 0) || havePrefix)
{
return(false);
}
havePrefix = true;
expectingNumber = true;
break;
case '.':
if (haveIPv4Address)
{
return(false);
}
i = end;
if (!IPv4AddressHelper.IsValid(name, lastSequence, ref i, true, false, false))
{
return(false);
}
// ipv4 address takes 2 slots in ipv6 address, one was just counted meeting the '.'
++sequenceCount;
haveIPv4Address = true;
--i; // it will be incremented back on the next loop
break;
default:
return(false);
}
sequenceLength = 0;
}
}
//
// if the last token was a prefix, check number of digits
//
if (havePrefix && ((sequenceLength < 1) || (sequenceLength > 2)))
{
return(false);
}
//
// these sequence counts are -1 because it is implied in end-of-sequence
//
int expectedSequenceCount = 8 + (havePrefix ? 1 : 0);
if (!expectingNumber && (sequenceLength <= 4) && (haveCompressor ? (sequenceCount < expectedSequenceCount) : (sequenceCount == expectedSequenceCount)))
{
if (i == end + 1)
{
// ']' was found
end = start + 1;
return(true);
}
return(false);
}
return(false);
}
//
// Parse
//
// Convert this IPv6 address into a sequence of 8 16-bit numbers
//
// Inputs:
// <member> Name
// The validated IPv6 address
//
// Outputs:
// <member> numbers
// Array filled in with the numbers in the IPv6 groups
//
// <member> PrefixLength
// Set to the number after the prefix separator (/) if found
//
// Assumes:
// <Name> has been validated and contains only hex digits in groups of
// 16-bit numbers, the characters ':' and '/', and a possible IPv4
// address
//
// Returns:
// true if this is a loopback, false otherwise. There is no failure indication as the sting must be a valid one.
//
// Throws:
// Nothing
//
internal static unsafe bool Parse(string address, ushort *numbers, int start, ref string scopeId)
{
int number = 0;
int index = 0;
int compressorIndex = -1;
bool numberIsValid = true;
//This used to be a class instance member but have not been used so far
int PrefixLength = 0;
if (address[start] == '[')
{
++start;
}
for (int i = start; i < address.Length && address[i] != ']';)
{
switch (address[i])
{
case '%':
if (numberIsValid)
{
numbers[index++] = (ushort)number;
numberIsValid = false;
}
start = i;
for (++i; address[i] != ']' && address[i] != '/'; ++i)
{
;
}
scopeId = address.Substring(start, i - start);
// ignore prefix if any
for (; address[i] != ']'; ++i)
{
;
}
break;
case ':':
numbers[index++] = (ushort)number;
number = 0;
++i;
if (address[i] == ':')
{
compressorIndex = index;
++i;
}
else if ((compressorIndex < 0) && (index < 6))
{
//
// no point checking for IPv4 address if we don't
// have a compressor or we haven't seen 6 16-bit
// numbers yet
//
break;
}
//
// check to see if the upcoming number is really an IPv4
// address. If it is, convert it to 2 ushort numbers
//
for (int j = i; (address[j] != ']') &&
(address[j] != ':') &&
(address[j] != '%') &&
(address[j] != '/') &&
(j < i + 4); ++j)
{
if (address[j] == '.')
{
//
// we have an IPv4 address. Find the end of it:
// we know that since we have a valid IPv6
// address, the only things that will terminate
// the IPv4 address are the prefix delimiter '/'
// or the end-of-string (which we conveniently
// delimited with ']')
//
while ((address[j] != ']') && (address[j] != '/') && (address[j] != '%'))
{
++j;
}
number = IPv4AddressHelper.ParseHostNumber(address, i, j);
unchecked
{
numbers[index++] = (ushort)(number >> 16);
numbers[index++] = (ushort)number;
}
i = j;
//
// set this to avoid adding another number to
// the array if there's a prefix
//
number = 0;
numberIsValid = false;
break;
}
}
break;
case '/':
if (numberIsValid)
{
numbers[index++] = (ushort)number;
numberIsValid = false;
}
//
// since we have a valid IPv6 address string, the prefix
// length is the last token in the string
//
for (++i; address[i] != ']'; ++i)
{
PrefixLength = PrefixLength * 10 + (address[i] - '0');
}
break;
default:
number = number * 16 + Uri.FromHex(address[i++]);
break;
}
}
//
// add number to the array if its not the prefix length or part of
// an IPv4 address that's already been handled
//
if (numberIsValid)
{
numbers[index++] = (ushort)number;
}
//
// if we had a compressor sequence ("::") then we need to expand the
// numbers array
//
if (compressorIndex > 0)
{
int toIndex = NumberOfLabels - 1;
int fromIndex = index - 1;
for (int i = index - compressorIndex; i > 0; --i)
{
numbers[toIndex--] = numbers[fromIndex];
numbers[fromIndex--] = 0;
}
}
//
// is the address loopback? Loopback is defined as one of:
//
// 0:0:0:0:0:0:0:1
// 0:0:0:0:0:0:127.0.0.1 == 0:0:0:0:0:0:7F00:0001
// 0:0:0:0:0:FFFF:127.0.0.1 == 0:0:0:0:0:FFFF:7F00:0001
//
return(((numbers[0] == 0) &&
(numbers[1] == 0) &&
(numbers[2] == 0) &&
(numbers[3] == 0) &&
(numbers[4] == 0)) &&
(((numbers[5] == 0) &&
(numbers[6] == 0) &&
(numbers[7] == 1)) ||
(((numbers[6] == 0x7F00) &&
(numbers[7] == 0x0001)) &&
((numbers[5] == 0) ||
(numbers[5] == 0xFFFF)))));
}
internal unsafe static bool IsValidStrict(char *name, int start, ref int end)
{
int sequenceCount = 0;
int sequenceLength = 0;
bool haveCompressor = false;
bool haveIPv4Address = false;
bool expectingNumber = true;
int lastSequence = 1;
bool needsClosingBracket = false;
if (start < end && name[start] == '[')
{
start++;
needsClosingBracket = true;
// IsValidStrict() is only called if there is a ':' in the name string, i.e.
// it is a possible IPv6 address. So, if the string starts with a '[' and
// the pointer is advanced here there are still more characters to parse.
Debug.Assert(start < end);
}
// Starting with a colon character is only valid if another colon follows.
if (name[start] == ':' && (start + 1 >= end || name[start + 1] != ':'))
{
return(false);
}
int i;
for (i = start; i < end; ++i)
{
if (Uri.IsHexDigit(name[i]))
{
++sequenceLength;
expectingNumber = false;
}
else
{
if (sequenceLength > 4)
{
return(false);
}
if (sequenceLength != 0)
{
++sequenceCount;
lastSequence = i - sequenceLength;
sequenceLength = 0;
}
switch (name[i])
{
case '%':
while (i + 1 < end)
{
i++;
if (name[i] == ']')
{
goto case ']';
}
else if (name[i] == '/')
{
goto case '/';
}
}
break;
case ']':
if (!needsClosingBracket)
{
return(false);
}
needsClosingBracket = false;
// If there's more after the closing bracket, it must be a port.
// We don't use the port, but we still validate it.
if (i + 1 < end && name[i + 1] != ':')
{
return(false);
}
// If there is a port, it must either be a hexadecimal or decimal number.
if (i + 3 < end && name[i + 2] == '0' && name[i + 3] == 'x')
{
i += 4;
for (; i < end; i++)
{
if (!Uri.IsHexDigit(name[i]))
{
return(false);
}
}
}
else
{
i += 2;
for (; i < end; i++)
{
if (name[i] < '0' || name[i] > '9')
{
return(false);
}
}
}
continue;
case ':':
if ((i > 0) && (name[i - 1] == ':'))
{
if (haveCompressor)
{
// can only have one per IPv6 address
return(false);
}
haveCompressor = true;
expectingNumber = false;
}
else
{
expectingNumber = true;
}
break;
case '/':
return(false);
case '.':
if (haveIPv4Address)
{
return(false);
}
i = end;
if (!IPv4AddressHelper.IsValid(name, lastSequence, ref i, true, false, false))
{
return(false);
}
// ipv4 address takes 2 slots in ipv6 address, one was just counted meeting the '.'
++sequenceCount;
lastSequence = i - sequenceLength;
sequenceLength = 0;
haveIPv4Address = true;
--i; // it will be incremented back on the next loop
break;
default:
return(false);
}
sequenceLength = 0;
}
}
if (sequenceLength != 0)
{
if (sequenceLength > 4)
{
return(false);
}
++sequenceCount;
}
// these sequence counts are -1 because it is implied in end-of-sequence
const int ExpectedSequenceCount = 8;
return
(!expectingNumber &&
(haveCompressor ? (sequenceCount < ExpectedSequenceCount) : (sequenceCount == ExpectedSequenceCount)) &&
!needsClosingBracket);
}
internal static void Parse(ReadOnlySpan <char> address, Span <ushort> numbers, int start, ref string?scopeId)
{
int number = 0;
int index = 0;
int compressorIndex = -1;
bool numberIsValid = true;
//This used to be a class instance member but have not been used so far
int PrefixLength = 0;
if (address[start] == '[')
{
++start;
}
for (int i = start; i < address.Length && address[i] != ']';)
{
switch (address[i])
{
case '%':
if (numberIsValid)
{
numbers[index++] = (ushort)number;
numberIsValid = false;
}
start = i;
for (++i; i < address.Length && address[i] != ']' && address[i] != '/'; ++i)
{
}
scopeId = new string(address.Slice(start, i - start));
// ignore prefix if any
for (; i < address.Length && address[i] != ']'; ++i)
{
}
break;
case ':':
numbers[index++] = (ushort)number;
number = 0;
++i;
if (address[i] == ':')
{
compressorIndex = index;
++i;
}
else if ((compressorIndex < 0) && (index < 6))
{
// no point checking for IPv4 address if we don't
// have a compressor or we haven't seen 6 16-bit
// numbers yet
break;
}
// check to see if the upcoming number is really an IPv4
// address. If it is, convert it to 2 ushort numbers
for (int j = i; j < address.Length &&
(address[j] != ']') &&
(address[j] != ':') &&
(address[j] != '%') &&
(address[j] != '/') &&
(j < i + 4); ++j)
{
if (address[j] == '.')
{
// we have an IPv4 address. Find the end of it:
// we know that since we have a valid IPv6
// address, the only things that will terminate
// the IPv4 address are the prefix delimiter '/'
// or the end-of-string (which we conveniently
// delimited with ']')
while (j < address.Length && (address[j] != ']') && (address[j] != '/') && (address[j] != '%'))
{
++j;
}
number = IPv4AddressHelper.ParseHostNumber(address, i, j);
numbers[index++] = (ushort)(number >> 16);
numbers[index++] = (ushort)number;
i = j;
// set this to avoid adding another number to
// the array if there's a prefix
number = 0;
numberIsValid = false;
break;
}
}
break;
case '/':
if (numberIsValid)
{
numbers[index++] = (ushort)number;
numberIsValid = false;
}
// since we have a valid IPv6 address string, the prefix
// length is the last token in the string
for (++i; address[i] != ']'; ++i)
{
PrefixLength = PrefixLength * 10 + (address[i] - '0');
}
break;
default:
number = number * 16 + Uri.FromHex(address[i++]);
break;
}
}
// add number to the array if its not the prefix length or part of
// an IPv4 address that's already been handled
if (numberIsValid)
{
numbers[index++] = (ushort)number;
}
// if we had a compressor sequence ("::") then we need to expand the
// numbers array
if (compressorIndex > 0)
{
int toIndex = NumberOfLabels - 1;
int fromIndex = index - 1;
for (int i = index - compressorIndex; i > 0; --i)
{
numbers[toIndex--] = numbers[fromIndex];
numbers[fromIndex--] = 0;
}
}
}