Security-58286.1.32.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 59a256b367244fef735450945c709e7bb1e80fdf..0959b5595040c50434ef6881ede05a869b312bcc 100644 (file)
--- a/OSX/libsecurity_codesigning/lib/machorep.cpp
+++ b/OSX/libsecurity_codesigning/lib/machorep.cpp
@@ -29,6 +29,7 @@
 #include "reqmaker.h"
 #include <security_utilities/logging.h>
 #include <security_utilities/cfmunge.h>
+#include <security_utilities/casts.h>
 
 
 
@@ -160,6 +161,82 @@ size_t MachORep::signingLimit()
        return macho->signingExtent();
 }
 
+bool MachORep::needsExecSeg(const MachO& macho) {
+       if (const version_min_command *version = macho.findMinVersion()) {
+               uint32_t min = UINT32_MAX;
+
+               switch (macho.flip(version->cmd)) {
+                       case LC_VERSION_MIN_IPHONEOS:
+                       case LC_VERSION_MIN_TVOS:
+                               min = (11 << 16 | 0 << 8);
+                               break;
+                       case LC_VERSION_MIN_WATCHOS:
+                               min = (4 << 16 | 0 << 8);
+                               break;
+
+                       default:
+                               /* macOS currently does not get this. */
+                               return false;
+               }
+
+               if (macho.flip(version->version) >= min) {
+                       return true;
+               }
+       }
+
+       return false;
+}
+
+size_t MachORep::execSegBase(const Architecture *arch)
+{
+       auto_ptr<MachO> macho(arch ? mExecutable->architecture(*arch) : mExecutable->architecture());
+
+       if (!needsExecSeg(*macho)) {
+               return 0;
+       }
+
+       segment_command const * const text_cmd = macho->findSegment("__TEXT");
+
+       if (text_cmd == NULL) {
+               return 0;
+       }
+
+       size_t off = 0;
+
+       if (macho->is64()) {
+               off = int_cast<uint64_t,size_t>(reinterpret_cast<segment_command_64 const * const>(text_cmd)->fileoff);
+       } else {
+               off = text_cmd->fileoff;
+       }
+
+       return off;
+}
+
+size_t MachORep::execSegLimit(const Architecture *arch)
+{
+       auto_ptr<MachO> macho(arch ? mExecutable->architecture(*arch) : mExecutable->architecture());
+
+       if (!needsExecSeg(*macho)) {
+               return 0;
+       }
+
+       segment_command const * const text_cmd = macho->findSegment("__TEXT");
+
+       if (text_cmd == NULL) {
+               return 0;
+       }
+
+       size_t size = 0;
+
+       if (macho->is64()) {
+               size = int_cast<uint64_t,size_t>(reinterpret_cast<segment_command_64 const * const>(text_cmd)->filesize);
+       } else {
+               size = text_cmd->filesize;
+       }
+
+       return size;
+}
+
 
 //
 // We choose the binary identifier for a Mach-O binary as follows: