bool SkipCommand(string command, byte[] buffer, ref int index, int endIndex)
{
while (index < endIndex && commandIndex < command.Length)
{
if (buffer[index] != (byte)command[commandIndex])
{
state = SmtpAuthCommandState.Error;
break;
}
commandIndex++;
index++;
}
return(commandIndex == command.Length);
}
public IList <AuthenticationSecret> DetectSecrets(byte[] buffer, int offset, int count)
{
if (!IsAuthenticating || state == SmtpAuthCommandState.Error || count == 0)
{
return(EmptyAuthSecrets);
}
int endIndex = offset + count;
int index = offset;
if (state == SmtpAuthCommandState.Auth)
{
if (SkipCommand("AUTH ", buffer, ref index, endIndex))
{
state = SmtpAuthCommandState.AuthMechanism;
}
if (index >= endIndex || state == SmtpAuthCommandState.Error)
{
return(EmptyAuthSecrets);
}
}
if (state == SmtpAuthCommandState.AuthMechanism)
{
while (index < endIndex && buffer[index] != (byte)' ' && buffer[index] != (byte)'\r')
{
index++;
}
if (index < endIndex)
{
if (buffer[index] == (byte)' ')
{
state = SmtpAuthCommandState.AuthToken;
}
else
{
state = SmtpAuthCommandState.AuthNewLine;
}
index++;
}
if (index >= endIndex)
{
return(EmptyAuthSecrets);
}
}
if (state == SmtpAuthCommandState.AuthNewLine)
{
if (buffer[index] == (byte)'\n')
{
state = SmtpAuthCommandState.AuthToken;
index++;
}
else
{
state = SmtpAuthCommandState.Error;
}
if (index >= endIndex || state == SmtpAuthCommandState.Error)
{
return(EmptyAuthSecrets);
}
}
int startIndex = index;
while (index < endIndex && buffer[index] != (byte)'\r')
{
index++;
}
if (index < endIndex)
{
state = SmtpAuthCommandState.AuthNewLine;
}
if (index == startIndex)
{
return(EmptyAuthSecrets);
}
var secret = new AuthenticationSecret(startIndex, index - startIndex);
if (state == SmtpAuthCommandState.AuthNewLine)
{
index++;
if (index < endIndex)
{
if (buffer[index] == (byte)'\n')
{
state = SmtpAuthCommandState.AuthToken;
}
else
{
state = SmtpAuthCommandState.Error;
}
}
}
return(new AuthenticationSecret[] { secret });
}
