public static (int MinIndex, int MaxIndex) ValidateContiguous(this SslProtocols protocols, SslProtocols[] orderedSslProtocols)
{
// A contiguous range of protocols is required. Find the min and max of the range,
// or throw if it's non-contiguous or if no protocols are specified.
// First, mark all of the specified protocols.
Span<bool> protocolSet = stackalloc bool[orderedSslProtocols.Length];
for (int i = 0; i < orderedSslProtocols.Length; i++)
{
protocolSet[i] = (protocols & orderedSslProtocols[i]) != 0;
}
int minIndex = -1;
int maxIndex = -1;
// Loop through them, starting from the lowest.
for (int min = 0; min < protocolSet.Length; min++)
{
if (protocolSet[min])
{
// We found the first one that's set; that's the bottom of the range.
minIndex = min;
// Now loop from there to look for the max of the range.
for (int max = min + 1; max < protocolSet.Length; max++)
{
if (!protocolSet[max])
{
// We found the first one after the min that's not set; the top of the range
// is the one before this (which might be the same as the min).
maxIndex = max - 1;
// Finally, verify that nothing beyond this one is set, as that would be
// a discontiguous set of protocols.
for (int verifyNotSet = max + 1; verifyNotSet < protocolSet.Length; verifyNotSet++)
{
if (protocolSet[verifyNotSet])
{
throw new PlatformNotSupportedException(SR.Format(SR.net_security_sslprotocol_contiguous, protocols));
}
}
break;
}
}
break;
}
}
// If no protocols were set, throw.
if (minIndex == -1)
{
throw new PlatformNotSupportedException(SR.net_securityprotocolnotsupported);
}
// If we didn't find an unset protocol after the min, go all the way to the last one.
if (maxIndex == -1)
{
maxIndex = orderedSslProtocols.Length - 1;
}
return (minIndex, maxIndex);
}
}
