OSX/libsecurity_codesigning/lib/StaticCode.h

   1 /*
   2  * Copyright (c) 2006-2014 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 //
  25 // StaticCode - SecStaticCode API objects
  26 //
  27 #ifndef _H_STATICCODE
  28 #define _H_STATICCODE
  29
  30 #include "cs.h"
  31 #include "csutilities.h"
  32 #include "Requirements.h"
  33 #include "requirement.h"
  34 #include "diskrep.h"
  35 #include "codedirectory.h"
  36 #include <Security/SecTrust.h>
  37 #include <CoreFoundation/CFData.h>
  38 #include <security_utilities/dispatch.h>
  39
  40 namespace Security {
  41 namespace CodeSigning {
  42
  43
  44 class SecCode;
  45
  46
  47 //
  48 // A SecStaticCode object represents the file system version of some code.
  49 // There's a lot of pieces to this, and we'll bring them all into
  50 // memory here (lazily) and let you fondle them with ease.
  51 //
  52 // Note that concrete knowledge of where stuff is stored resides in the DiskRep
  53 // object we hold. DiskReps allocate, retrieve, and return data to us. We are
  54 // responsible for interpreting, caching, and validating them. (In other words,
  55 // DiskReps know where stuff is and how it is stored, but we know what it means.)
  56 //
  57 // Data accessors (returning CFDataRef, CFDictionaryRef, various pointers, etc.)
  58 // cache those values internally and return unretained(!) references ("Get" style)
  59 // that are valid as long as the SecStaticCode object's lifetime, or until
  60 // resetValidity() is called, whichever is sooner. If you need to keep them longer,
  61 // retain or copy them as needed.
  62 //
  63 class SecStaticCode : public SecCFObject {
  64         NOCOPY(SecStaticCode)
  65
  66 protected:
  67         //
  68         // A context for resource validation operations, to tailor error response.
  69         // The base class throws an exception immediately and ignores detail data.
  70         //
  71         class ValidationContext {
  72         public:
  73                 ValidationContext(SecStaticCode &c) : code(c) { }
  74                 virtual ~ValidationContext();
  75                 virtual void reportProblem(OSStatus rc, CFStringRef type, CFTypeRef value);
  76
  77                 virtual OSStatus osStatus()     { return noErr; }
  78                 virtual void throwMe()          { }
  79
  80                 SecStaticCode &code;
  81         };
  82
  83         //
  84         // A CollectingContext collects all error details and throws an annotated final error.
  85         //
  86         class CollectingContext : public ValidationContext {
  87         public:
  88                 CollectingContext(SecStaticCode &c) : ValidationContext(c), mStatus(errSecSuccess) { }
  89                 void reportProblem(OSStatus rc, CFStringRef type, CFTypeRef value);
  90
  91                 OSStatus osStatus()             { return mStatus; }
  92                 operator OSStatus () const              { return mStatus; }
  93                 void throwMe() __attribute__((noreturn));
  94
  95         private:
  96                 CFRef<CFMutableDictionaryRef> mCollection;
  97                 OSStatus mStatus;
  98                 Mutex mLock;
  99         };
 100
 101 public:
 102         SECCFFUNCTIONS(SecStaticCode, SecStaticCodeRef,
 103                 errSecCSInvalidObjectRef, gCFObjects().StaticCode)
 104
 105         // implicitly convert SecCodeRefs to their SecStaticCodeRefs
 106         static SecStaticCode *requiredStatic(SecStaticCodeRef ref);     // convert SecCodeRef
 107         static SecCode *optionalDynamic(SecStaticCodeRef ref); // extract SecCodeRef or NULL if static
 108
 109         SecStaticCode(DiskRep *rep);
 110     virtual ~SecStaticCode() throw();
 111
 112     void initializeFromParent(const SecStaticCode& parent);
 113
 114     bool equal(SecCFObject &other);
 115     CFHashCode hash();
 116
 117         void detachedSignature(CFDataRef sig);          // attach an explicitly given detached signature
 118         void checkForSystemSignature();                         // check for and attach system-supplied detached signature
 119
 120         const CodeDirectory *codeDirectory(bool check = true) const;
 121         CodeDirectory::HashAlgorithm hashAlgorithm() const { return codeDirectory()->hashType; }
 122         CodeDirectory::HashAlgorithms hashAlgorithms() const { return mHashAlgorithms; }
 123         CFDataRef cdHash();
 124         CFArrayRef cdHashes();
 125         CFDataRef signature();
 126         CFAbsoluteTime signingTime();
 127         CFAbsoluteTime signingTimestamp();
 128         bool isSigned() { return codeDirectory(false) != NULL; }
 129         DiskRep *diskRep() const { return mRep; }
 130         bool isDetached() const { return mRep->base() != mRep; }
 131         std::string mainExecutablePath() { return mRep->mainExecutablePath(); }
 132         CFURLRef copyCanonicalPath() const { return mRep->copyCanonicalPath(); }
 133         std::string identifier() { return codeDirectory()->identifier(); }
 134         const char *teamID() { return codeDirectory()->teamID(); }
 135         std::string format() const { return mRep->format(); }
 136         std::string signatureSource();
 137         virtual CFDataRef component(CodeDirectory::SpecialSlot slot, OSStatus fail = errSecCSSignatureFailed);
 138         virtual CFDictionaryRef infoDictionary();
 139         CFDictionaryRef diskRepInformation();
 140
 141         CFDictionaryRef entitlements();
 142         CFDataRef copyComponent(CodeDirectory::SpecialSlot slot, CFDataRef hash);
 143
 144         CFDictionaryRef resourceDictionary(bool check = true);
 145         CFURLRef resourceBase();
 146         void validateResource(CFDictionaryRef files, std::string path, bool isSymlink, ValidationContext &ctx, SecCSFlags flags, uint32_t version);
 147         void validateSymlinkResource(std::string fullpath, std::string seal, ValidationContext &ctx, SecCSFlags flags);
 148
 149         bool flag(uint32_t tested);
 150
 151         SecCodeCallback monitor() const { return mMonitor; }
 152         void setMonitor(SecCodeCallback monitor) { mMonitor = monitor; }
 153         CFTypeRef reportEvent(CFStringRef stage, CFDictionaryRef info);
 154         void reportProgress(unsigned amount = 1);
 155
 156         void setValidationFlags(SecCSFlags flags) { mValidationFlags = flags; }
 157         void setValidationModifiers(CFDictionaryRef modifiers);
 158
 159         void resetValidity();                                           // clear validation caches (if something may have changed)
 160
 161         bool validated() const  { return mValidated; }
 162         bool revocationChecked() const { return mRevocationChecked; }
 163         bool valid() const
 164                 { assert(validated()); return mValidated && (mValidationResult == errSecSuccess); }
 165         bool validatedExecutable() const        { return mExecutableValidated; }
 166         bool validatedResources() const { return mResourcesValidated; }
 167
 168         void prepareProgress(unsigned workload);
 169         void cancelValidation();
 170
 171         void validateDirectory();
 172         virtual void validateComponent(CodeDirectory::SpecialSlot slot, OSStatus fail = errSecCSSignatureFailed);
 173         void validateNonResourceComponents();
 174         void validateTopDirectory();
 175         unsigned estimateResourceWorkload();
 176         void validateResources(SecCSFlags flags);
 177         void validateExecutable();
 178         void validateNestedCode(CFURLRef path, const ResourceSeal &seal, SecCSFlags flags, bool isFramework);
 179
 180         void validatePlainMemoryResource(string path, CFDataRef fileData, SecCSFlags flags);
 181
 182         const Requirements *internalRequirements();
 183         const Requirement *internalRequirement(SecRequirementType type);
 184         const Requirement *designatedRequirement();
 185         const Requirement *defaultDesignatedRequirement();              // newly allocated (caller owns)
 186
 187         void validateRequirements(SecRequirementType type, SecStaticCode *target,
 188                 OSStatus nullError = errSecSuccess);                                                                            // target against my [type], throws
 189         void validateRequirement(const Requirement *req, OSStatus failure);             // me against [req], throws
 190         bool satisfiesRequirement(const Requirement *req, OSStatus failure);    // me against [req], returns on clean miss
 191
 192         // certificates are available after signature validation (they are stored in the CMS signature)
 193         SecCertificateRef cert(int ix);         // get a cert from the cert chain
 194         CFArrayRef certificates();                      // get the entire certificate chain
 195
 196         CFDictionaryRef signingInformation(SecCSFlags flags); // omnibus information-gathering API (creates new dictionary)
 197
 198         static bool isAppleDeveloperCert(CFArrayRef certs); // determines if this is an apple developer certificate for library validation
 199
 200 public:
 201         void staticValidate(SecCSFlags flags, const SecRequirement *req);
 202         void staticValidateCore(SecCSFlags flags, const SecRequirement *req);
 203
 204 protected:
 205         typedef std::map<CodeDirectory::HashAlgorithm, CFCopyRef<CFDataRef> > CodeDirectoryMap;
 206         bool loadCodeDirectories(CodeDirectoryMap& cdMap) const;
 207
 208 protected:
 209         CFDictionaryRef getDictionary(CodeDirectory::SpecialSlot slot, bool check = true); // component value as a dictionary
 210         bool verifySignature();
 211         CFArrayRef verificationPolicies();
 212
 213         // load preferred rules/files dictionaries (cached therein)
 214         bool loadResources(CFDictionaryRef& rules, CFDictionaryRef& files, uint32_t& version);
 215
 216         static void checkOptionalResource(CFTypeRef key, CFTypeRef value, void *context);
 217         bool hasWeakResourceRules(CFDictionaryRef rulesDict, uint32_t version, CFArrayRef allowedOmissions);
 218
 219         void handleOtherArchitectures(void (^handle)(SecStaticCode* other));
 220
 221 private:
 222         void validateOtherVersions(CFURLRef path, SecCSFlags flags, SecRequirementRef req, SecStaticCode *code);
 223
 224 private:
 225         RefPointer<DiskRep> mRep;                       // on-disk representation
 226         mutable CodeDirectoryMap mCodeDirectories; // available CodeDirectory blobs by digest type
 227         mutable CFRef<CFDataRef> mBaseDir;      // the primary CodeDirectory blob (whether it's chosen or not)
 228         CFRef<CFDataRef> mDetachedSig;          // currently applied explicit detached signature
 229
 230         // private validation modifiers (only used by Gatekeeper checkfixes)
 231         MacOSErrorSet mTolerateErrors;          // soft error conditions to ignore
 232         CFRef<CFArrayRef> mAllowOmissions;      // additionally allowed resource omissions
 233
 234         // master validation state
 235         bool mValidated;                                        // core validation was attempted
 236         bool mRevocationChecked;                        // the signature was checked for revocation
 237         OSStatus mValidationResult;                     // outcome of core validation
 238         bool mValidationExpired;                        // outcome had expired certificates
 239
 240         // static executable validation state (nested within mValidated/mValid)
 241         bool mExecutableValidated;                      // tried to validate executable file
 242         OSStatus mExecutableValidResult;                // outcome if mExecutableValidated
 243
 244         // static resource validation state (nested within mValidated/mValid)
 245         bool mResourcesValidated;                       // tried to validate resources
 246         bool mResourcesDeep;                            // cached validation was deep
 247         OSStatus mResourcesValidResult;                 // outcome if mResourceValidated or...
 248         ValidationContext *mResourcesValidContext; // resource error reporting funnel
 249
 250         // validation progress state (set when static validation starts)
 251         SecCSFlags mValidationFlags;            // API flags passed to static validation
 252         unsigned mTotalWork;                            // total expected work (arbitrary units)
 253         unsigned mCurrentWork;                          // currently completed work
 254         bool mCancelPending;                            // cancellation was requested
 255         Dispatch::Queue mProgressQueue;         // progress reporting queue
 256
 257         // nested validation support
 258         const SecStaticCode *mOuterScope;       // containing code (if this is a nested validation; weak)
 259         ResourceBuilder *mResourceScope;        // current Resource validation stack (while validating; weak)
 260
 261         // cached contents
 262         mutable CFRef<CFDataRef> mDir;          // code directory data
 263         mutable CodeDirectory::HashAlgorithms mHashAlgorithms; // available hash algorithms
 264         CFRef<CFDataRef> mSignature;            // CMS signature data
 265         CFAbsoluteTime mSigningTime;            // (signed) signing time
 266         CFAbsoluteTime mSigningTimestamp;               // Timestamp time (from timestamping authority)
 267         CFRef<CFDataRef> mCache[cdSlotCount]; // NULL => not tried, kCFNull => absent, other => present
 268
 269         // alternative cache forms (storage may depend on cached contents above)
 270         CFRef<CFDictionaryRef> mInfoDict;       // derived from mCache slot
 271         CFRef<CFDictionaryRef> mEntitlements; // derived from mCache slot
 272         CFRef<CFDictionaryRef> mResourceDict; // derived from mCache slot
 273         const Requirement *mDesignatedReq;      // cached designated req if we made one up
 274         CFRef<CFDataRef> mCDHash;                       // hash of chosen CodeDirectory
 275         CFRef<CFArrayRef> mCDHashes;            // hashes of all CodeDirectories (in digest type code order)
 276
 277         bool mGotResourceBase;                          // asked mRep for resourceBasePath
 278         CFRef<CFURLRef> mResourceBase;          // URL form of resource base directory
 279
 280         SecCodeCallback mMonitor;                       // registered monitor callback
 281
 282         LimitedAsync *mLimitedAsync;            // limited async workers for verification
 283
 284         // signature verification outcome (mTrust == NULL => not done yet)
 285         CFRef<SecTrustRef> mTrust;                      // outcome of crypto validation (valid or not)
 286         CFRef<CFArrayRef> mCertChain;
 287         CSSM_TP_APPLE_EVIDENCE_INFO *mEvalDetails;
 288 };
 289
 290
 291 } // end namespace CodeSigning
 292 } // end namespace Security
 293
 294 #endif // !_H_STATICCODE