Merge pull request #58 from p-x9/feature/code-signature

Code Signature

Sources/MachOKit/Extension/Sequence+.swift

@@ -310,3 +310,17 @@ extension Sequence where Element == MachOImage.Symbol {
         return nil
     }
 }
+
+extension Sequence where Element == CodeSignCodeDirectory {
+    public var bestHashTyped: CodeSignCodeDirectory? {
+        let hashTypes: [CodeSignHashType] = [
+            .sha384,
+            .sha256,
+            .sha256_truncated,
+            .sha1
+        ]
+        return self.min(by: { lhs, rhs in
+            hashTypes.firstIndex(of: lhs.hashType)! < hashTypes.firstIndex(of: rhs.hashType)!
+        })
+    }
+}

Sources/MachOKit/MachOFile+CodeSign.swift

@@ -0,0 +1,140 @@
+//
+//  MachOFile+CodeSign.swift
+//
+//
+//  Created by p-x9 on 2024/03/03.
+//
+//
+
+import Foundation
+import MachOKitC
+
+extension MachOFile {
+    public struct CodeSign {
+        public let data: Data
+        public let isSwapped: Bool // bigEndian => false
+    }
+}
+
+extension MachOFile.CodeSign {
+    init(data: Data) {
+        self.data = data
+        self.isSwapped = CFByteOrderGetCurrent() != CFByteOrderBigEndian.rawValue
+    }
+}
+
+extension MachOFile.CodeSign: CodeSignProtocol {
+    public var superBlob: CodeSignSuperBlob? {
+        data.withUnsafeBytes {
+            guard let basePtr = $0.baseAddress else { return nil }
+            var layout = basePtr.assumingMemoryBound(to: CS_SuperBlob.self).pointee
+            if isSwapped { layout = layout.swapped }
+            return .init(
+                layout: layout,
+                offset: 0
+            )
+        }
+    }
+
+    public var codeDirectories: [CodeSignCodeDirectory] {
+        data.withUnsafeBytes { bufferPointer in
+            guard let baseAddress = bufferPointer.baseAddress,
+                  let superBlob else {
+                return []
+            }
+            let blobIndices = superBlob.blobIndices(in: self)
+            return blobIndices
+                .compactMap {
+                    let offset: Int = numericCast($0.offset)
+                    let ptr = baseAddress.advanced(by: offset)
+                    let _blob = ptr.assumingMemoryBound(to: CS_GenericBlob.self).pointee
+                    let blob = CodeSignGenericBlob(
+                        layout: isSwapped ? _blob.swapped : _blob
+                    )
+                    guard blob.magic == .codedirectory else {
+                        return nil
+                    }
+                    return (
+                        ptr.assumingMemoryBound(to: CS_CodeDirectory.self).pointee,
+                        offset
+                    )
+                }
+                .map {
+                    isSwapped ? .init(layout: $0.swapped, offset: $1)
+                    : .init(layout: $0, offset: $1)
+                }
+        }
+    }
+
+    public var requirementsBlob: CodeSignSuperBlob? {
+        guard let superBlob else {
+            return nil
+        }
+        let blobIndices = superBlob.blobIndices(in: self)
+        guard let index = blobIndices.first(
+            where: { $0.type == .requirements }
+        ) else {
+            return nil
+        }
+        return data.withUnsafeBytes { bufferPointer in
+            guard let baseAddress = bufferPointer.baseAddress else {
+                return nil
+            }
+            let offset: Int = numericCast(index.offset)
+            let ptr = baseAddress.advanced(by: offset)
+            var _blob = ptr
+                .assumingMemoryBound(to: CS_SuperBlob.self)
+                .pointee
+            if isSwapped { _blob = _blob.swapped }
+
+            return .init(
+                layout: _blob,
+                offset: offset
+            )
+        }
+    }
+}
+
+extension MachOFile.CodeSign {
+    /// Get blob data as `Data`
+    /// - Parameters:
+    ///   - superBlob: SuperBlob to which index belongs
+    ///   - index: Index of the blob to be gotten
+    ///   - includesGenericInfo: A boolean value that indicates whether the data defined in the ``CodeSignGenericBlob``, such as magic and length, are included or not.
+    /// - Returns: Data of blob
+    ///
+    /// Note that when converting from this data to other blob models, byte swapping must be performed appropriately for the ``MachOFile.CodeSign.isSwapped`` parameter.
+    public func blobData(
+        in superBlob: CodeSignSuperBlob,
+        at index: CodeSignBlobIndex,
+        includesGenericInfo: Bool = true
+    ) -> Data? {
+        data.withUnsafeBytes { bufferPointer in
+            guard let baseAddress = bufferPointer.baseAddress else {
+                return nil
+            }
+            let offset: Int = numericCast(superBlob.offset) + numericCast(index.offset)
+            guard let _blob: CodeSignGenericBlob = .load(
+                from: baseAddress,
+                offset: offset,
+                isSwapped: isSwapped
+            ) else { return nil }
+
+            let data = Data(
+                bytes: baseAddress.advanced(by: offset),
+                count: numericCast(_blob.length)
+            )
+            if includesGenericInfo {
+                return data
+            } else {
+                return data.advanced(by: CodeSignGenericBlob.layoutSize)
+            }
+        }
+    }
+
+    public func blobIndices(
+        of superBlob: CodeSignSuperBlob
+    ) -> AnySequence<CodeSignBlobIndex> {
+        superBlob.blobIndices(in: self)
+    }
+}

Sources/MachOKit/MachOFile.swift

@@ -412,3 +412,17 @@ extension MachOFile {
         return false
     }
 }
+
+extension MachOFile {
+    public var codeSign: CodeSign? {
+        guard let info = loadCommands.codeSignature else {
+            return nil
+        }
+        let data = fileHandle.readData(
+            offset: UInt64(headerStartOffset) + numericCast(info.dataoff),
+            size: numericCast(info.datasize)
+        )
+
+        return .init(data: data)
+    }
+}

Sources/MachOKit/MachOImage+CodeSign.swift

@@ -0,0 +1,171 @@
+//
+//  MachOImage+CodeSign.swift
+//
+//
+//  Created by p-x9 on 2024/03/10.
+//  
+//
+
+import Foundation
+
+extension MachOImage {
+    public struct CodeSign {
+        public let basePointer: UnsafeRawPointer
+        public let codeSignatureSize: Int
+        public let isSwapped: Bool // bigEndian => false
+    }
+}
+
+extension MachOImage.CodeSign: CodeSignProtocol {
+    init?(
+        codeSignature: linkedit_data_command,
+        linkedit: SegmentCommand64,
+        vmaddrSlide: Int
+    ) {
+        guard let linkeditStartPtr = linkedit.startPtr(
+            vmaddrSlide: vmaddrSlide
+        ) else {
+            return nil
+        }
+
+        let start = linkeditStartPtr
+            .advanced(by: -numericCast(linkedit.fileoff))
+            .advanced(by: numericCast(codeSignature.dataoff))
+        let size: Int = numericCast(codeSignature.datasize)
+        let isSwapped = CFByteOrderGetCurrent() != CFByteOrderBigEndian.rawValue
+
+        self.init(
+            basePointer: start,
+            codeSignatureSize: size,
+            isSwapped: isSwapped
+        )
+    }
+
+    init?(
+        codeSignature: linkedit_data_command,
+        linkedit: SegmentCommand,
+        vmaddrSlide: Int
+    ) {
+        guard let linkeditStartPtr = linkedit.startPtr(
+            vmaddrSlide: vmaddrSlide
+        ) else {
+            return nil
+        }
+
+        let start = linkeditStartPtr
+            .advanced(by: -numericCast(linkedit.fileoff))
+            .advanced(by: numericCast(codeSignature.dataoff))
+            .assumingMemoryBound(to: UInt8.self)
+        let size: Int = numericCast(codeSignature.datasize)
+        let isSwapped = CFByteOrderGetCurrent() != CFByteOrderBigEndian.rawValue
+
+        self.init(
+            basePointer: start,
+            codeSignatureSize: size,
+            isSwapped: isSwapped
+        )
+    }
+}
+
+extension MachOImage.CodeSign {
+    public var superBlob: CodeSignSuperBlob? {
+        var layout = basePointer
+            .assumingMemoryBound(to: CS_SuperBlob.self)
+            .pointee
+        if isSwapped { layout = layout.swapped }
+        return .init(
+            layout: layout,
+            offset: 0
+        )
+    }
+
+    public var codeDirectories: [CodeSignCodeDirectory] {
+        guard let superBlob else {
+            return []
+        }
+        let blobIndices = superBlob.blobIndices(in: self)
+        return blobIndices
+            .compactMap {
+                let offset: Int = numericCast($0.offset)
+                let ptr = basePointer.advanced(by: offset)
+                let _blob = ptr.assumingMemoryBound(to: CS_GenericBlob.self).pointee
+                let blob = CodeSignGenericBlob(
+                    layout: isSwapped ? _blob.swapped : _blob
+                )
+                guard blob.magic == .codedirectory else {
+                    return nil
+                }
+                return (
+                    ptr.assumingMemoryBound(to: CS_CodeDirectory.self).pointee,
+                    offset
+                )
+            }
+            .map {
+                isSwapped ? .init(layout: $0.swapped, offset: $1)
+                : .init(layout: $0, offset: $1)
+            }
+    }
+
+    public var requirementsBlob: CodeSignSuperBlob? {
+        guard let superBlob else {
+            return nil
+        }
+        let blobIndices = superBlob.blobIndices(in: self)
+        guard let index = blobIndices.first(
+            where: { $0.type == .requirements }
+        ) else {
+            return nil
+        }
+
+        let offset: Int = numericCast(index.offset)
+        let ptr = basePointer.advanced(by: offset)
+        var _blob = ptr
+            .assumingMemoryBound(to: CS_SuperBlob.self)
+            .pointee
+        if isSwapped { _blob = _blob.swapped }
+
+        return .init(
+            layout: _blob,
+            offset: offset
+        )
+    }
+}
+
+extension MachOImage.CodeSign {
+    /// Get blob data as `Data`
+    /// - Parameters:
+    ///   - superBlob: SuperBlob to which index belongs
+    ///   - index: Index of the blob to be gotten
+    ///   - includesGenericInfo: A boolean value that indicates whether the data defined in the ``CodeSignGenericBlob``, such as magic and length, are included or not.
+    /// - Returns: Data of blob
+    ///
+    /// Note that when converting from this data to other blob models, byte swapping must be performed appropriately for the ``MachOImage.CodeSign.isSwapped`` parameter.
+    public func blobData(
+        in superBlob: CodeSignSuperBlob,
+        at index: CodeSignBlobIndex,
+        includesGenericInfo: Bool = true
+    ) -> Data? {
+        let offset: Int = numericCast(superBlob.offset) + numericCast(index.offset)
+        guard let _blob: CodeSignGenericBlob = .load(
+            from: basePointer,
+            offset: offset,
+            isSwapped: isSwapped
+        ) else { return nil }
+
+        let data = Data(
+            bytes: basePointer.advanced(by: offset),
+            count: numericCast(_blob.length)
+        )
+        if includesGenericInfo {
+            return data
+        } else {
+            return data.advanced(by: CodeSignGenericBlob.layoutSize)
+        }
+    }
+
+    public func blobIndices(
+        of superBlob: CodeSignSuperBlob
+    ) -> AnySequence<CodeSignBlobIndex> {
+        superBlob.blobIndices(in: self)
+    }
+}

Sources/MachOKit/MachOImage.swift

@@ -543,3 +543,28 @@ extension MachOImage {
         return nil
     }
 }
+
+extension MachOImage {
+    public var codeSign: CodeSign? {
+        guard let vmaddrSlide,
+              let codeSignature = loadCommands.codeSignature,
+              codeSignature.datasize > 0 else {
+            return nil
+        }
+
+        if let linkedit = loadCommands.linkedit64 {
+            return .init(
+                codeSignature: codeSignature.layout,
+                linkedit: linkedit,
+                vmaddrSlide: vmaddrSlide
+            )
+        } else if let linkedit = loadCommands.linkedit {
+            return .init(
+                codeSignature: codeSignature.layout,
+                linkedit: linkedit,
+                vmaddrSlide: vmaddrSlide
+            )
+        }
+        return nil
+    }
+}