internal TypeSymbol GetTypeSymbol(MetadataHelpers.AssemblyQualifiedTypeName fullName, out bool refersToNoPiaLocalType)
{
//
// Section 23.3 (Custom Attributes) of CLI Spec Partition II:
//
// If the parameter kind is System.Type, (also, the middle line in above diagram) its value is
// stored as a SerString (as defined in the previous paragraph), representing its canonical name.
// The canonical name is its full type name, followed optionally by the assembly where it is defined,
// its version, culture and public-key-token. If the assembly name is omitted, the CLI looks first
// in the current assembly, and then in the system library (mscorlib); in these two special cases,
// it is permitted to omit the assembly-name, version, culture and public-key-token.
int referencedAssemblyIndex;
if (fullName.AssemblyName != null)
{
AssemblyIdentity identity;
if (!AssemblyIdentity.TryParseDisplayName(fullName.AssemblyName, out identity))
{
refersToNoPiaLocalType = false;
return(GetUnsupportedMetadataTypeSymbol());
}
// the assembly name has to be a full name:
referencedAssemblyIndex = GetIndexOfReferencedAssembly(identity);
if (referencedAssemblyIndex == -1)
{
// In rare cases (e.g. assemblies emitted by Reflection.Emit) the identity
// might be the identity of the containing assembly. The metadata spec doesn't disallow this.
if (!this.IsContainingAssembly(identity))
{
refersToNoPiaLocalType = false;
return(GetUnsupportedMetadataTypeSymbol());
}
}
}
else
{
// Use this assembly
referencedAssemblyIndex = -1;
}
// Find the top level type
Debug.Assert(MetadataHelpers.IsValidMetadataIdentifier(fullName.TopLevelType));
var mdName = MetadataTypeName.FromFullName(fullName.TopLevelType);
TypeSymbol container = LookupTopLevelTypeDefSymbol(ref mdName, referencedAssemblyIndex, out refersToNoPiaLocalType);
// Process any nested types
if (fullName.NestedTypes != null)
{
if (refersToNoPiaLocalType)
{
// Types nested into local types are not supported.
refersToNoPiaLocalType = false;
return(GetUnsupportedMetadataTypeSymbol());
}
for (int i = 0; i < fullName.NestedTypes.Length; i++)
{
Debug.Assert(MetadataHelpers.IsValidMetadataIdentifier(fullName.NestedTypes[i]));
mdName = MetadataTypeName.FromTypeName(fullName.NestedTypes[i]);
// Find nested type in the container
container = LookupNestedTypeDefSymbol(container, ref mdName);
}
}
// Substitute type arguments if any
if (fullName.TypeArguments != null)
{
ImmutableArray <bool> argumentRefersToNoPiaLocalType;
var typeArguments = ResolveTypeArguments(fullName.TypeArguments, out argumentRefersToNoPiaLocalType);
container = SubstituteTypeParameters(container, typeArguments, argumentRefersToNoPiaLocalType);
foreach (bool flag in argumentRefersToNoPiaLocalType)
{
if (flag)
{
refersToNoPiaLocalType = true;
break;
}
}
}
else
{
container = SubstituteWithUnboundIfGeneric(container);
}
for (int i = 0; i < fullName.PointerCount; i++)
{
container = MakePointerTypeSymbol(container, ImmutableArray <ModifierInfo <TypeSymbol> > .Empty);
}
// Process any array type ranks
if (fullName.ArrayRanks != null)
{
foreach (int rank in fullName.ArrayRanks)
{
Debug.Assert(rank == 0);
container = GetSZArrayTypeSymbol(container, default(ImmutableArray <ModifierInfo <TypeSymbol> >));
}
}
return(container);
}
protected abstract bool IsContainingAssembly(AssemblyIdentity identity);
/// <summary>
/// Given that an assembly with identity assemblyGrantingAccessIdentity granted access to assemblyWantingAccess,
/// check the public keys to ensure the internals-visible-to check should succeed. This is used by both the
/// C# and VB implementations as a helper to implement `bool IAssemblySymbol.GivesAccessTo(IAssemblySymbol toAssembly)`.
/// </summary>
internal static IVTConclusion PerformIVTCheck(
this AssemblyIdentity assemblyGrantingAccessIdentity,
ImmutableArray <byte> assemblyWantingAccessKey,
ImmutableArray <byte> grantedToPublicKey)
{
// This gets a bit complicated. Let's break it down.
//
// First off, let's assume that the "other" assembly is GrantingAssembly.DLL, that the "this"
// assembly is "WantingAssembly.DLL", and that GrantingAssembly has named WantingAssembly as a friend (that is a precondition
// to calling this method). Whether we allow WantingAssembly to see internals of GrantingAssembly depends on these four factors:
//
// q1) Is GrantingAssembly strong-named?
// q2) Did GrantingAssembly name WantingAssembly as a friend via a strong name?
// q3) Is WantingAssembly strong-named?
// q4) Does GrantingAssembly give a strong-name for WantingAssembly that matches our strong name?
//
// Before we dive into the details, we should mention two additional facts:
//
// * If the answer to q1 is "yes", and GrantingAssembly was compiled by a Roslyn compiler, then q2 must be "yes" also.
// Strong-named GrantingAssembly must only be friends with strong-named WantingAssembly. See the blog article
// http://blogs.msdn.com/b/ericlippert/archive/2009/06/04/alas-smith-and-jones.aspx
// for an explanation of why this feature is desirable.
//
// Now, just because the compiler enforces this rule does not mean that we will never run into
// a scenario where GrantingAssembly is strong-named and names WantingAssembly via a weak name. Not all assemblies
// were compiled with a Roslyn compiler. We still need to deal sensibly with this situation.
// We do so by ignoring the problem; if strong-named GrantingAssembly extends friendship to weak-named
// WantingAssembly then we're done; any assembly named WantingAssembly is a friend of GrantingAssembly.
//
// Incidentally, the C# compiler produces error CS1726, ERR_FriendAssemblySNReq, and VB produces
// the error VB31535, ERR_FriendAssemblyStrongNameRequired, when compiling
// a strong-named GrantingAssembly that names a weak-named WantingAssembly as its friend.
//
// * If the answer to q1 is "no" and the answer to q3 is "yes" then we are in a situation where
// strong-named WantingAssembly is referencing weak-named GrantingAssembly, which is illegal. In the dev10 compiler
// we do not give an error about this until emit time. In Roslyn we have a new error, CS7029,
// which we give before emit time when we detect that weak-named GrantingAssembly has given friend access
// to strong-named WantingAssembly, which then references GrantingAssembly. However, we still want to give friend
// access to WantingAssembly for the purposes of semantic analysis.
//
// Roslyn C# does not yet give an error in other circumstances whereby a strong-named assembly
// references a weak-named assembly. See https://github.com/dotnet/roslyn/issues/26722
//
// Let's make a chart that illustrates all the possible answers to these four questions, and
// what the resulting accessibility should be:
//
// case q1 q2 q3 q4 Result Explanation
// 1 YES YES YES YES SUCCESS GrantingAssembly has named this strong-named WantingAssembly as a friend.
// 2 YES YES YES NO NO MATCH GrantingAssembly has named a different strong-named WantingAssembly as a friend.
// 3 YES YES NO NO NO MATCH GrantingAssembly has named a strong-named WantingAssembly as a friend, but this WantingAssembly is weak-named.
// 4 YES NO YES NO SUCCESS GrantingAssembly has improperly (*) named any WantingAssembly as its friend. But we honor its offer of friendship.
// 5 YES NO NO NO SUCCESS GrantingAssembly has improperly (*) named any WantingAssembly as its friend. But we honor its offer of friendship.
// 6 NO YES YES YES SUCCESS, BAD REF GrantingAssembly has named this strong-named WantingAssembly as a friend, but WantingAssembly should not be referring to a weak-named GrantingAssembly.
// 7 NO YES YES NO NO MATCH GrantingAssembly has named a different strong-named WantingAssembly as a friend.
// 8 NO YES NO NO NO MATCH GrantingAssembly has named a strong-named WantingAssembly as a friend, but this WantingAssembly is weak-named.
// 9 NO NO YES NO SUCCESS, BAD REF GrantingAssembly has named any WantingAssembly as a friend, but WantingAssembly should not be referring to a weak-named GrantingAssembly.
// 10 NO NO NO NO SUCCESS GrantingAssembly has named any WantingAssembly as its friend.
//
// (*) GrantingAssembly was not built with a Roslyn compiler, which would have prevented this.
//
// This method never returns NoRelationshipClaimed because if control got here, then we assume
// (as a precondition) that GrantingAssembly named WantingAssembly as a friend somehow.
bool q1 = assemblyGrantingAccessIdentity.IsStrongName;
bool q2 = !grantedToPublicKey.IsDefaultOrEmpty;
bool q3 = !assemblyWantingAccessKey.IsDefaultOrEmpty;
bool q4 = (q2 & q3) && ByteSequenceComparer.Equals(grantedToPublicKey, assemblyWantingAccessKey);
// Cases 2, 3, 7 and 8:
if (q2 && !q4)
{
return(IVTConclusion.PublicKeyDoesntMatch);
}
// Cases 6 and 9:
if (!q1 && q3)
{
return(IVTConclusion.OneSignedOneNot);
}
// Cases 1, 4, 5 and 10:
return(IVTConclusion.Match);
}
internal override bool ApplyUnificationPolicies(
ref AssemblyIdentity reference,
ref AssemblyIdentity definition,
AssemblyIdentityParts referenceParts,
out bool isDefinitionFxAssembly)
{
if (reference.ContentType == AssemblyContentType.Default &&
SimpleNameComparer.Equals(reference.Name, definition.Name) &&
SimpleNameComparer.Equals(reference.Name, "mscorlib"))
{
isDefinitionFxAssembly = true;
reference = definition;
return(true);
}
if (!reference.IsRetargetable && definition.IsRetargetable)
{
// Reference is not retargetable, but definition is retargetable.
// Non-equivalent.
isDefinitionFxAssembly = false;
return(false);
}
// Notes:
// an assembly might be both retargetable and portable
// in that case retargetable table acts as an override.
// Apply portability policy transforms first (e.g. rewrites references to SL assemblies to their desktop equivalents)
// If the reference is partial and is missing version or PKT it is not ported.
reference = Port(reference);
definition = Port(definition);
if (reference.IsRetargetable && !definition.IsRetargetable)
{
if (!AssemblyIdentity.IsFullName(referenceParts))
{
isDefinitionFxAssembly = false;
return(false);
}
// Reference needs to be retargeted before comparison,
// unless it's optionally retargetable and we already match the PK
bool skipRetargeting = IsOptionallyRetargetableAssembly(reference) &&
AssemblyIdentity.KeysEqual(reference, definition);
if (!skipRetargeting)
{
reference = Retarget(reference);
}
}
// At this point we are in one of the following states:
//
// 1) Both ref/def are not retargetable
// 2) Both ref/def are retargetable
// 3) Ref is retargetable (and has been retargeted)
//
// We can do a straight compare of ref/def at this point using the
// regular rules
if (reference.IsRetargetable && definition.IsRetargetable)
{
isDefinitionFxAssembly = IsRetargetableAssembly(definition);
}
else
{
isDefinitionFxAssembly = IsFrameworkAssembly(definition);
}
return(true);
}
/// <summary> /// Resolves a missing assembly reference. /// </summary> /// <param name="definition">The metadata definition (assembly or module) that declares assembly reference <paramref name="referenceIdentity"/> in its list of dependencies.</param> /// <param name="referenceIdentity">Identity of the assembly reference that couldn't be resolved against metadata references explicitly specified to in the compilation.</param> /// <returns>Resolved reference or null if the identity can't be resolved.</returns> public virtual PortableExecutableReference ResolveMissingAssembly(MetadataReference definition, AssemblyIdentity referenceIdentity) => null;
// Windows[.winmd]
internal static bool IsWindowsRuntime(this AssemblyIdentity identity)
{
return((identity.ContentType == AssemblyContentType.WindowsRuntime) &&
string.Equals(identity.Name, "windows", StringComparison.OrdinalIgnoreCase));
}
// Windows.*[.winmd]
internal static bool IsWindowsComponent(this AssemblyIdentity identity)
{
return((identity.ContentType == AssemblyContentType.WindowsRuntime) &&
identity.Name.StartsWith("windows.", StringComparison.OrdinalIgnoreCase));
}
