Security-57337.60.2.tar.gz

[apple/security.git] / OSX / libsecurity_codesigning / lib / machorep.cpp

diff --git a/OSX/libsecurity_codesigning/lib/machorep.cpp b/OSX/libsecurity_codesigning/lib/machorep.cpp
index d362b5ab9d82dbf4c8b07c77d0007cddda80ddae..de4b43a4a099d02b68cf2c2e0c3a4797544c226c 100644 (file)
--- a/OSX/libsecurity_codesigning/lib/machorep.cpp
+++ b/OSX/libsecurity_codesigning/lib/machorep.cpp
@@ -97,6 +97,50 @@ Universal *MachORep::mainExecutableImage()
        return mExecutable;
 }
 
+       
+//
+// Explicitly default to SHA256 (only) digests if the minimum deployment
+// target is young enough.
+//
+void MachORep::prepareForSigning(SigningContext &context)
+{
+       if (context.digestAlgorithms().empty()) {
+               MachO *macho = mainExecutableImage()->architecture();
+               if (const version_min_command *version = macho->findMinVersion()) {
+                       uint32_t limit = 0;
+                       switch (macho->flip(version->cmd)) {
+                       case LC_VERSION_MIN_MACOSX:
+                               limit = (10 << 16 | 11 << 8 | 4 << 0);
+                               break;
+#if 0 /* need updated libMIS before we can do this switch */
+                       case LC_VERSION_MIN_IPHONEOS:
+                               limit = (9 << 16 | 3 << 8);
+                               break;
+                       case LC_VERSION_MIN_WATCHOS:
+                               limit = (2 << 16 | 2 << 8);
+                               break;
+                       case LC_VERSION_MIN_TVOS:
+                               limit = (9 << 16 | 2 << 8);
+                               break;
+                       default:
+                               break;
+#else
+            case LC_VERSION_MIN_IPHONEOS:
+            case LC_VERSION_MIN_WATCHOS:
+            case LC_VERSION_MIN_TVOS:
+                return;
+            default:
+                break;
+#endif
+                       }
+                       if (macho->flip(version->version) >= limit) {
+                               // young enough not to need SHA-1 legacy support
+                               context.setDigestAlgorithm(kSecCodeSignatureHashSHA256);
+                       }
+               }
+       }
+}
+
 
 //
 // Signing base is the start of the Mach-O architecture we're using
@@ -368,8 +412,10 @@ size_t MachORep::pageSize(const SigningContext &)
 //
 // Strict validation
 //
-void MachORep::strictValidate(const CodeDirectory* cd, const ToleratedErrors& tolerated)
+void MachORep::strictValidate(const CodeDirectory* cd, const ToleratedErrors& tolerated, SecCSFlags flags)
 {
+       DiskRep::strictValidate(cd, tolerated, flags);
+       
        // if the constructor found suspicious issues, fail a struct validation now
        if (mExecutable->isSuspicious() && tolerated.find(errSecCSBadMainExecutable) == tolerated.end())
                MacOSError::throwMe(errSecCSBadMainExecutable);
@@ -377,7 +423,7 @@ void MachORep::strictValidate(const CodeDirectory* cd, const ToleratedErrors& to
        // the signature's code extent must be what we would have picked (no funny hand editing)
        if (cd) {
                auto_ptr<MachO> macho(mExecutable->architecture());
-               if (cd->codeLimit != macho->signingExtent())
+               if (cd->signingLimit() != macho->signingExtent())
                        MacOSError::throwMe(errSecCSSignatureInvalid);
        }
 }