/// <summary>
/// Creates a SQRLIdentity object from the specified <paramref name="file"/>.
/// </summary>
/// <param name="file">The full file path of the identity file to be parsed.</param>
/// <returns>The imported identity object, or <c>null</c> if the file does not exist.</returns>
public static SQRLIdentity FromFile(string file)
{
if (!File.Exists(file))
{
return(null);
}
byte[] fileBytes = File.ReadAllBytes(file);
return(SQRLIdentity.FromByteArray(fileBytes));
}
/// <summary>
/// Parses a SQRL identity from the given <paramref name="identityData"/> byte array.
/// </summary>
/// <param name="identityData">The raw byte representation of a SQRL identity.</param>
/// <param name="noHeader">Indicates whether the plaintext sqrl header is missing and checking for it should be skipped or not.</param>
public static SQRLIdentity FromByteArray(byte[] identityData, bool noHeader = false)
{
SQRLIdentity id = new SQRLIdentity();
bool isBase64 = false;
int skip = SQRLHEADER.Length;
// Check header
if (!noHeader)
{
string sqrlHeader = System.Text.Encoding.UTF8.GetString(identityData.Take(8).ToArray());
if (!sqrlHeader.Equals(SQRLHEADER, StringComparison.OrdinalIgnoreCase))
{
Log.Error($"Error parsing identity from byte array: No SQRL header found!");
throw new IOException("Invalid File Exception, not a valid SQRL Identity File");
}
if (sqrlHeader.Equals(SQRLHEADER.ToUpper()))
{
isBase64 = true;
}
}
else
{
skip = 0;
}
// Remove header
identityData = identityData.Skip(skip).ToArray();
// If we're dealing with a base64url-encoded identity,
// decode it to binary first
if (isBase64)
{
identityData = Sodium.Utilities.Base64ToBinary(
System.Text.Encoding.UTF8.GetString(identityData), string.Empty, Sodium.Utilities.Base64Variant.UrlSafeNoPadding);
}
int i = 0;
while (i < identityData.Length)
{
// we need to be able to read type and length
if (i + 4 > identityData.Length)
{
break;
}
ushort blockLength = BitConverter.ToUInt16(identityData.Skip(i).Take(2).ToArray());
ushort blockType = BitConverter.ToUInt16(identityData.Skip(i + 2).Take(2).ToArray());
// check if specified length exceeds real length
if (i + blockLength > identityData.Length)
{
break;
}
switch (blockType)
{
case 0:
SQRLBlock0 block0 = new SQRLBlock0();
block0.FromByteArray(identityData.Skip(i).Take(blockLength).ToArray());
id.Blocks.Add(block0);
break;
case 1:
SQRLBlock1 block1 = new SQRLBlock1();
block1.FromByteArray(identityData.Skip(i).Take(blockLength).ToArray());
id.Blocks.Add(block1);
break;
case 2:
SQRLBlock2 block2 = new SQRLBlock2();
block2.FromByteArray(identityData.Skip(i).Take(blockLength).ToArray());
id.Blocks.Add(block2);
break;
case 3:
SQRLBlock3 block3 = new SQRLBlock3();
block3.FromByteArray(identityData.Skip(i).Take(blockLength).ToArray());
id.Blocks.Add(block3);
break;
default:
SQRLBlock block = new SQRLBlock();
block.FromByteArray(identityData.Skip(i).Take(blockLength).ToArray());
id.Blocks.Add(block);
break;
}
i += blockLength;
}
return(id);
}