wismna/modernkeepass
1
0
Fork 0
mirror of https://github.com/wismna/ModernKeePass.git synced 2025-10-03 23:50:18 -04:00
Code Issues Packages Projects Releases Wiki Activity

WIP Lib version 2.39.1

Browse Source
This commit is contained in:
BONNEVILLE Geoffroy
2018-05-22 18:27:44 +02:00
parent 0b95669db0
commit ad02740d8a
43 changed files with 1469 additions and 522 deletions
Download Patch File Download Diff File Expand all files Collapse all files

204
ModernKeePassLib/Security/ProtectedString.cs
View File

@@ -33,11 +33,11 @@ using KeePassLibSD;
namespace ModernKeePassLib.Security
{
/// <summary>
/// Represents an in-memory encrypted string.
/// A string that is protected in process memory.
/// <c>ProtectedString</c> objects are immutable and thread-safe.
/// </summary>
#if (DEBUG && !KeePassLibSD)
[DebuggerDisplay(@"{ReadString()}")]
[DebuggerDisplay("{ReadString()}")]
#endif
public sealed class ProtectedString
{
@@ -48,11 +48,24 @@ namespace ModernKeePassLib.Security
private bool m_bIsProtected;
private static readonly ProtectedString m_psEmpty = new ProtectedString();
/// <summary>
/// Get an empty <c>ProtectedString</c> object, without protection.
/// </summary>
public static ProtectedString Empty
{
get { return m_psEmpty; }
}
private static readonly ProtectedString m_psEmptyEx = new ProtectedString(
true, new byte[0]);
/// <summary>
/// Get an empty <c>ProtectedString</c> object, with protection turned on.
/// </summary>
public static ProtectedString EmptyEx
{
get { return m_psEmptyEx; }
}
/// <summary>
/// A flag specifying whether the <c>ProtectedString</c> object
/// has turned on memory protection or not.
@@ -66,8 +79,8 @@ namespace ModernKeePassLib.Security
{
get
{
ProtectedBinary pBin = m_pbUtf8; // Local ref for thread-safety
if(pBin != null) return (pBin.Length == 0);
ProtectedBinary p = m_pbUtf8; // Local ref for thread-safety
if(p != null) return (p.Length == 0);
Debug.Assert(m_strPlainText != null);
return (m_strPlainText.Length == 0);
@@ -75,18 +88,21 @@ namespace ModernKeePassLib.Security
}
private int m_nCachedLength = -1;
/// <summary>
/// Length of the protected string, in characters.
/// </summary>
public int Length
{
get
{
if(m_nCachedLength >= 0) return m_nCachedLength;
ProtectedBinary pBin = m_pbUtf8; // Local ref for thread-safety
if(pBin != null)
ProtectedBinary p = m_pbUtf8; // Local ref for thread-safety
if(p != null)
{
byte[] pbPlain = pBin.ReadData();
m_nCachedLength = StrUtil.Utf8.GetCharCount(pbPlain);
MemUtil.ZeroByteArray(pbPlain);
byte[] pbPlain = p.ReadData();
try { m_nCachedLength = StrUtil.Utf8.GetCharCount(pbPlain); }
finally { MemUtil.ZeroByteArray(pbPlain); }
}
else
{
@@ -149,9 +165,8 @@ namespace ModernKeePassLib.Security
if(xbProtected == null) throw new ArgumentNullException("xbProtected");
byte[] pb = xbProtected.ReadPlainText();
Init(bEnableProtection, pb);
if(bEnableProtection) MemUtil.ZeroByteArray(pb);
try { Init(bEnableProtection, pb); }
finally { if(bEnableProtection) MemUtil.ZeroByteArray(pb); }
}
private void Init(bool bEnableProtection, string str)
@@ -160,7 +175,7 @@ namespace ModernKeePassLib.Security
m_bIsProtected = bEnableProtection;
// The string already is in memory and immutable,
// As the string already is in memory and immutable,
// protection would be useless
m_strPlainText = str;
}
@@ -178,8 +193,8 @@ namespace ModernKeePassLib.Security
}
/// <summary>
/// Convert the protected string to a normal string object.
/// Be careful with this function, the returned string object
/// Convert the protected string to a standard string object.
/// Be careful with this function, as the returned string object
/// isn't protected anymore and stored in plain-text in the
/// process memory.
/// </summary>
@@ -194,23 +209,42 @@ namespace ModernKeePassLib.Security
// No need to clear pb
// As the text is now visible in process memory anyway,
// there's no need to protect it anymore
// there's no need to protect it anymore (strings are
// immutable and thus cannot be overwritten)
m_strPlainText = str;
m_pbUtf8 = null; // Thread-safe order
return str;
}
/// <summary>
/// Read out the string and return it as a char array.
/// The returned array is not protected and should be cleared by
/// the caller.
/// </summary>
/// <returns>Plain-text char array.</returns>
public char[] ReadChars()
{
if(m_strPlainText != null) return m_strPlainText.ToCharArray();
byte[] pb = ReadUtf8();
char[] v;
try { v = StrUtil.Utf8.GetChars(pb); }
finally { MemUtil.ZeroByteArray(pb); }
return v;
}
/// <summary>
/// Read out the string and return a byte array that contains the
/// string encoded using UTF-8. The returned string is not protected
/// anymore!
/// string encoded using UTF-8.
/// The returned array is not protected and should be cleared by
/// the caller.
/// </summary>
/// <returns>Plain-text UTF-8 byte array.</returns>
public byte[] ReadUtf8()
{
ProtectedBinary pBin = m_pbUtf8; // Local ref for thread-safety
if(pBin != null) return pBin.ReadData();
ProtectedBinary p = m_pbUtf8; // Local ref for thread-safety
if(p != null) return p.ReadData();
return StrUtil.Utf8.GetBytes(m_strPlainText);
}
@@ -223,7 +257,7 @@ namespace ModernKeePassLib.Security
/// <returns>Protected string.</returns>
public byte[] ReadXorredString(CryptoRandomStream crsRandomSource)
{
Debug.Assert(crsRandomSource != null); if(crsRandomSource == null) throw new ArgumentNullException("crsRandomSource");
if(crsRandomSource == null) { Debug.Assert(false); throw new ArgumentNullException("crsRandomSource"); }
byte[] pbData = ReadUtf8();
uint uLen = (uint)pbData.Length;
@@ -242,10 +276,34 @@ namespace ModernKeePassLib.Security
if(bProtect == m_bIsProtected) return this;
byte[] pb = ReadUtf8();
ProtectedString ps = new ProtectedString(bProtect, pb);
if(bProtect) MemUtil.ZeroByteArray(pb);
return ps;
// No need to clear pb; either the current or the new object is unprotected
return new ProtectedString(bProtect, pb);
}
public bool Equals(ProtectedString ps, bool bCheckProtEqual)
{
if(ps == null) throw new ArgumentNullException("ps");
if(object.ReferenceEquals(this, ps)) return true; // Perf. opt.
bool bPA = m_bIsProtected, bPB = ps.m_bIsProtected;
if(bCheckProtEqual && (bPA != bPB)) return false;
if(!bPA && !bPB) return (ReadString() == ps.ReadString());
byte[] pbA = ReadUtf8(), pbB = null;
bool bEq;
try
{
pbB = ps.ReadUtf8();
bEq = MemUtil.ArraysEqual(pbA, pbB);
}
finally
{
if(bPA) MemUtil.ZeroByteArray(pbA);
if(bPB && (pbB != null)) MemUtil.ZeroByteArray(pbB);
}
return bEq;
}
public ProtectedString Insert(int iStart, string strInsert)
@@ -254,18 +312,14 @@ namespace ModernKeePassLib.Security
if(strInsert == null) throw new ArgumentNullException("strInsert");
if(strInsert.Length == 0) return this;
// Only operate directly with strings when m_bIsProtected is
// false, not in the case of non-null m_strPlainText, because
// the operation creates a new sequence in memory
if(!m_bIsProtected)
return new ProtectedString(false, ReadString().Insert(
iStart, strInsert));
UTF8Encoding utf8 = StrUtil.Utf8;
byte[] pb = ReadUtf8();
char[] v = utf8.GetChars(pb);
char[] vNew;
char[] v = ReadChars(), vNew = null;
byte[] pbNew = null;
ProtectedString ps;
try
{
@@ -279,21 +333,20 @@ namespace ModernKeePassLib.Security
Array.Copy(vIns, 0, vNew, iStart, vIns.Length);
Array.Copy(v, iStart, vNew, iStart + vIns.Length,
v.Length - iStart);
pbNew = utf8.GetBytes(vNew);
ps = new ProtectedString(true, pbNew);
Debug.Assert(utf8.GetString(pbNew, 0, pbNew.Length) ==
ReadString().Insert(iStart, strInsert));
}
finally
{
MemUtil.ZeroArray<char>(v);
MemUtil.ZeroByteArray(pb);
if(vNew != null) MemUtil.ZeroArray<char>(vNew);
if(pbNew != null) MemUtil.ZeroByteArray(pbNew);
}
byte[] pbNew = utf8.GetBytes(vNew);
ProtectedString ps = new ProtectedString(m_bIsProtected, pbNew);
Debug.Assert(utf8.GetString(pbNew, 0, pbNew.Length) ==
ReadString().Insert(iStart, strInsert));
MemUtil.ZeroArray<char>(vNew);
MemUtil.ZeroByteArray(pbNew);
return ps;
}
@@ -303,44 +356,81 @@ namespace ModernKeePassLib.Security
if(nCount < 0) throw new ArgumentOutOfRangeException("nCount");
if(nCount == 0) return this;
// Only operate directly with strings when m_bIsProtected is
// false, not in the case of non-null m_strPlainText, because
// the operation creates a new sequence in memory
if(!m_bIsProtected)
return new ProtectedString(false, ReadString().Remove(
iStart, nCount));
UTF8Encoding utf8 = StrUtil.Utf8;
byte[] pb = ReadUtf8();
char[] v = utf8.GetChars(pb);
char[] vNew;
char[] v = ReadChars(), vNew = null;
byte[] pbNew = null;
ProtectedString ps;
try
{
if((iStart + nCount) > v.Length)
throw new ArgumentException("iStart + nCount");
throw new ArgumentException("(iStart + nCount) > v.Length");
vNew = new char[v.Length - nCount];
Array.Copy(v, 0, vNew, 0, iStart);
Array.Copy(v, iStart + nCount, vNew, iStart, v.Length -
(iStart + nCount));
pbNew = utf8.GetBytes(vNew);
ps = new ProtectedString(true, pbNew);
Debug.Assert(utf8.GetString(pbNew, 0, pbNew.Length) ==
ReadString().Remove(iStart, nCount));
}
finally
{
MemUtil.ZeroArray<char>(v);
MemUtil.ZeroByteArray(pb);
if(vNew != null) MemUtil.ZeroArray<char>(vNew);
if(pbNew != null) MemUtil.ZeroByteArray(pbNew);
}
byte[] pbNew = utf8.GetBytes(vNew);
ProtectedString ps = new ProtectedString(m_bIsProtected, pbNew);
Debug.Assert(utf8.GetString(pbNew, 0, pbNew.Length) ==
ReadString().Remove(iStart, nCount));
MemUtil.ZeroArray<char>(vNew);
MemUtil.ZeroByteArray(pbNew);
return ps;
}
public static ProtectedString operator +(ProtectedString a, ProtectedString b)
{
if(a == null) throw new ArgumentNullException("a");
if(b == null) throw new ArgumentNullException("b");
if(b.IsEmpty) return a;
if(a.IsEmpty) return b;
if(!a.IsProtected && !b.IsProtected)
return new ProtectedString(false, a.ReadString() + b.ReadString());
char[] vA = a.ReadChars(), vB = null, vNew = null;
byte[] pbNew = null;
ProtectedString ps;
try
{
vB = b.ReadChars();
vNew = new char[vA.Length + vB.Length];
Array.Copy(vA, vNew, vA.Length);
Array.Copy(vB, 0, vNew, vA.Length, vB.Length);
pbNew = StrUtil.Utf8.GetBytes(vNew);
ps = new ProtectedString(true, pbNew);
}
finally
{
MemUtil.ZeroArray<char>(vA);
if(vB != null) MemUtil.ZeroArray<char>(vB);
if(vNew != null) MemUtil.ZeroArray<char>(vNew);
if(pbNew != null) MemUtil.ZeroByteArray(pbNew);
}
return ps;
}
public static ProtectedString operator +(ProtectedString a, string b)
{
ProtectedString psB = new ProtectedString(false, b);
return (a + psB);
}
}
}