libsecurity_codesigning/lib/SecCode.h

   1 /*
   2  * Copyright (c) 2006-2010 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         @header SecCode
  26         SecCode represents separately indentified running code in the system.
  27         In addition to UNIX processes, this can also include (with suitable support)
  28         scripts, applets, widgets, etc.
  29 */
  30 #ifndef _H_SECCODE
  31 #define _H_SECCODE
  32
  33 #include <Security/CSCommon.h>
  34
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39
  40 /*!
  41         @function SecCodeGetTypeID
  42         Returns the type identifier of all SecCode instances.
  43 */
  44 CFTypeID SecCodeGetTypeID(void);
  45
  46
  47 /*!
  48         @function SecCodeCopySelf
  49         Obtains a SecCode object for the code making the call.
  50         The calling code is determined in a way that is subject to modification over
  51         time, but obeys the following rules. If it is a UNIX process, its process id (pid)
  52         is always used. If it is an active code host that has a dedicated guest, such a guest
  53         is always preferred. If it is a host that has called SecHostSelectGuest, such selection
  54         is considered until revoked.
  55
  56         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
  57         @param self Upon successful return, contains a SecCodeRef representing the caller.
  58
  59         @result Upon success, errSecSuccess. Upon error, an OSStatus value documented in
  60         CSCommon.h or certain other Security framework headers.
  61  */
  62 OSStatus SecCodeCopySelf(SecCSFlags flags, SecCodeRef *self);
  63
  64
  65 /*!
  66         @function SecCodeCopyStaticCode
  67         Given a SecCode object, locate its origin in the file system and return
  68         a SecStaticCode object representing it.
  69
  70         The link established by this call is generally reliable but is NOT guaranteed
  71         to be secure.
  72
  73         Many API functions taking SecStaticCodeRef arguments will also directly
  74         accept a SecCodeRef and apply this translation implicitly, operating on
  75         its result or returning its error code if any. Each of these functions
  76         calls out that behavior in its documentation.
  77
  78         If the code was obtained from a universal (aka "fat") program file,
  79         the resulting SecStaticCodeRef will refer only to the architecture actually
  80         being used. This means that multiple running codes started from the same file
  81         may conceivably result in different static code references if they ended up
  82         using different execution architectures. (This is unusual but possible.)
  83
  84         @param code A valid SecCode object reference representing code running
  85         on the system.
  86
  87         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
  88         @constant kSecCSUseAllArchitectures
  89         If code refers to a single architecture of a universal binary, return a SecStaticCodeRef
  90         that refers to the entire universal code with all its architectures. By default, the
  91         returned static reference identifies only the actual architecture of the running program.
  92
  93         @param staticCode On successful return, a SecStaticCode object reference representing
  94         the file system origin of the given SecCode. On error, unchanged.
  95         @result Upon success, errSecSuccess. Upon error, an OSStatus value documented in
  96         CSCommon.h or certain other Security framework headers.
  97 */
  98 enum {
  99         kSecCSUseAllArchitectures = 1 << 0,
 100 };
 101
 102 OSStatus SecCodeCopyStaticCode(SecCodeRef code, SecCSFlags flags, SecStaticCodeRef *staticCode);
 103
 104
 105 /*!
 106         @function SecCodeCopyHost
 107         Given a SecCode object, identify the (different) SecCode object that acts
 108         as its host. A SecCode's host acts as a supervisor and controller,
 109         and is the ultimate authority on the its dynamic validity and status.
 110         The host relationship is securely established (absent reported errors).
 111
 112         @param code A valid SecCode object reference representing code running
 113         on the system.
 114         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 115         @param host On successful return, a SecCode object reference identifying
 116         the code's host.
 117         @result Upon success, errSecSuccess. Upon error, an OSStatus value documented in
 118         CSCommon.h or certain other Security framework headers.
 119 */
 120 OSStatus SecCodeCopyHost(SecCodeRef guest, SecCSFlags flags, SecCodeRef *host);
 121
 122
 123 /*!
 124         @function SecCodeCopyGuestWithAttributes
 125         This is the omnibus API function for obtaining dynamic code references.
 126         In general, it asks a particular code acting as a code host to locate
 127         and return a guest with given attributes. Different hosts support
 128         different combinations of attributes and values for guest selection.
 129
 130         Asking the NULL host invokes system default     procedures for obtaining
 131         any running code in the system with the attributes given. The returned
 132         code may be anywhere in the system.
 133
 134         The methods a host uses to identify, separate, and control its guests
 135         are specific to each type of host. This call provides a generic abstraction layer
 136         that allows uniform interrogation of all hosts. A SecCode that does not
 137         act as a host will always return errSecCSNoSuchCode. A SecCode that does
 138         support hosting may return itself to signify that the attribute refers to
 139         itself rather than one of its hosts.
 140
 141         @param host A valid SecCode object reference representing code running
 142         on the system that acts as a Code Signing host. As a special case, passing
 143         NULL indicates that the Code Signing root of trust should be used as a starting
 144         point. Currently, that is the system kernel.
 145         @param attributes A CFDictionary containing zero or more attribute selector
 146         values. Each selector has a CFString key and associated CFTypeRef value.
 147         The key name identifies the attribute being specified; the associated value,
 148         whose type depends on the the key name, selects a particular value or other
 149         constraint on that attribute. Each host only supports particular combinations
 150         of keys and values,     and errors will be returned if any unsupported set is requested.
 151         As a special case, NULL is taken to mean an empty attribute set.
 152         Note that some hosts that support hosting chains (guests being hosts)
 153         may return sub-guests in this call. In other words, do not assume that
 154         a SecCodeRef returned by this call is a direct guest of the queried host
 155         (though it will be a proximate guest, i.e. a guest's guest some way down).
 156         Asking the NULL host for NULL attributes returns a code reference for the system root
 157         of trust (at present, the running Darwin kernel).
 158         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 159         @param guest On successful return, a SecCode object reference identifying
 160         the particular guest of the host that owns the attribute value(s) specified.
 161         This argument will not be changed if the call fails (does not return errSecSuccess).
 162         @result Upon success, errSecSuccess. Upon error, an OSStatus value documented in
 163         CSCommon.h or certain other Security framework headers. In particular:
 164         @error errSecCSUnsupportedGuestAttributes The host does not support the attribute
 165         type given by attributeType.
 166         @error errSecCSInvalidAttributeValues The type of value given for a guest
 167         attribute is not supported by the host.
 168         @error errSecCSNoSuchCode The host has no guest with the attribute value given
 169         by attributeValue, even though the value is of a supported type. This may also
 170         be returned if the host code does not currently act as a Code Signing host.
 171         @error errSecCSNotAHost The specified host cannot, in fact, act as a code
 172         host. (It is missing the kSecCodeSignatureHost option flag in its code
 173         signature.)
 174         @error errSecCSMultipleGuests The attributes specified do not uniquely identify
 175         a guest (the specification is ambiguous).
 176 */
 177 extern const CFStringRef kSecGuestAttributeCanonical;
 178 extern const CFStringRef kSecGuestAttributeHash;
 179 extern const CFStringRef kSecGuestAttributeMachPort;
 180 extern const CFStringRef kSecGuestAttributePid;
 181 extern const CFStringRef kSecGuestAttributeDynamicCode;
 182 extern const CFStringRef kSecGuestAttributeDynamicCodeInfoPlist;
 183 extern const CFStringRef kSecGuestAttributeArchitecture;
 184 extern const CFStringRef kSecGuestAttributeSubarchitecture;
 185
 186 OSStatus SecCodeCopyGuestWithAttributes(SecCodeRef host,
 187         CFDictionaryRef attributes,     SecCSFlags flags, SecCodeRef *guest);
 188
 189
 190 /*!
 191         @function SecCodeCheckValidity
 192         Performs dynamic validation of the given SecCode object. The call obtains and
 193         verifies the signature on the code object. It checks the validity of only those
 194         sealed components required to establish identity. It checks the SecCode's
 195         dynamic validity status as reported by its host. It ensures that the SecCode's
 196         host is in turn valid. Finally, it validates the code against a SecRequirement
 197         if one is given. The call succeeds if all these conditions are satisfactory.
 198         It fails otherwise.
 199
 200         This call is secure against attempts to modify the file system source of the
 201         SecCode.
 202
 203         @param code The code object to be validated.
 204         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 205         @param requirement An optional code requirement specifying additional conditions
 206         the code object must satisfy to be considered valid. If NULL, no additional
 207         requirements are imposed.
 208         @param errors An optional pointer to a CFErrorRef variable. If the call fails
 209         (and something other than errSecSuccess is returned), and this argument is non-NULL,
 210         a CFErrorRef is stored there further describing the nature and circumstances
 211         of the failure. The caller must CFRelease() this error object when done with it.
 212         @result If validation passes, errSecSuccess. If validation fails, an OSStatus value
 213         documented in CSCommon.h or certain other Security framework headers.
 214 */
 215 OSStatus SecCodeCheckValidity(SecCodeRef code, SecCSFlags flags,
 216         SecRequirementRef requirement);
 217
 218 OSStatus SecCodeCheckValidityWithErrors(SecCodeRef code, SecCSFlags flags,
 219         SecRequirementRef requirement, CFErrorRef *errors);
 220
 221
 222 /*!
 223         @function SecCodeCopyPath
 224         For a given Code or StaticCode object, returns a URL to a location on disk where the
 225         code object can be found. For single files, the URL points to that file.
 226         For bundles, it points to the directory containing the entire bundle.
 227
 228         This returns the same URL as the kSecCodeInfoMainExecutable key returned
 229         by SecCodeCopySigningInformation.
 230
 231         @param code The Code or StaticCode object to be located. For a Code
 232                 argument, its StaticCode is processed as per SecCodeCopyStaticCode.
 233         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 234         @param path On successful return, contains a CFURL identifying the location
 235         on disk of the staticCode object.
 236         @result On success, errSecSuccess. On error, an OSStatus value
 237         documented in CSCommon.h or certain other Security framework headers.
 238 */
 239 OSStatus SecCodeCopyPath(SecStaticCodeRef staticCode, SecCSFlags flags,
 240         CFURLRef *path);
 241
 242
 243 /*!
 244         @function SecCodeCopyDesignatedRequirement
 245         For a given Code or StaticCode object, determines its Designated Code Requirement.
 246         The Designated Requirement is the SecRequirement that the code believes
 247         should be used to properly identify it in the future.
 248
 249         If the SecCode contains an explicit Designated Requirement, a copy of that
 250         is returned. If it does not, a SecRequirement is implicitly constructed from
 251         its signing authority and its embedded unique identifier. No Designated
 252         Requirement can be obtained from code that is unsigned. Code that is modified
 253         after signature, improperly signed, or has become invalid, may or may not yield
 254         a Designated Requirement. This call does not validate the SecStaticCode argument.
 255
 256         @param code The Code or StaticCode object to be interrogated. For a Code
 257                 argument, its StaticCode is processed as per SecCodeCopyStaticCode.
 258         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 259         @param requirement On successful return, contains a copy of a SecRequirement
 260         object representing the code's Designated Requirement. On error, unchanged.
 261         @result On success, errSecSuccess. On error, an OSStatus value
 262                 documented in CSCommon.h or certain other Security framework headers.
 263 */
 264 OSStatus SecCodeCopyDesignatedRequirement(SecStaticCodeRef code, SecCSFlags flags,
 265         SecRequirementRef *requirement);
 266
 267
 268 /*
 269         @function SecCodeCopySigningInformation
 270         For a given Code or StaticCode object, extract various pieces of information
 271         from its code signature and return them in the form of a CFDictionary. The amount
 272         and detail level of the data is controlled by the flags passed to the call.
 273
 274         If the code exists but is not signed at all, this call will succeed and return
 275         a dictionary that does NOT contain the kSecCodeInfoIdentifier key. This is the
 276         recommended way to check quickly whether a code is signed.
 277
 278         If the signing data for the code is corrupt or invalid, this call may fail or it
 279         may return partial data. To ensure that only valid data is returned (and errors
 280         are raised for invalid data), you must successfully call one of the CheckValidity
 281         functions on the code before calling CopySigningInformation.
 282
 283         @param code The Code or StaticCode object to be interrogated. For a Code
 284                 argument, its StaticCode is processed as per SecCodeCopyStaticCode.
 285                 Note that dynamic information (kSecCSDynamicInformation) cannot be obtained
 286                 for a StaticCode argument.
 287         @param flags Optional flags. Use any or all of the kSecCS*Information flags
 288                 to select what information to return. A generic set of entries is returned
 289                 regardless; you may specify kSecCSDefaultFlags for just those.
 290         @param information A CFDictionary containing information about the code is stored
 291                 here on successful completion. The contents of the dictionary depend on
 292                 the flags passed. Regardless of flags, the kSecCodeInfoIdentifier key is
 293                 always present if the code is signed, and always absent if the code is
 294                 unsigned.
 295                 Note that some of the objects returned are (retained) "live" API objects
 296                 used by the code signing infrastructure. Making changes to these objects
 297                 is unsupported and may cause subsequent code signing operations on the
 298                 affected code to behave in undefined ways.
 299         @result On success, errSecSuccess. On error, an OSStatus value
 300                 documented in CSCommon.h or certain other Security framework headers.
 301
 302         Flags:
 303
 304         @constant kSecCSSigningInformation Return cryptographic signing information,
 305                 including the certificate chain and CMS data (if any). For ad-hoc signed
 306                 code, there are no certificates and the CMS data is empty.
 307         @constant kSecCSRequirementInformation Return information about internal code
 308                 requirements embedded in the code. This includes the Designated Requirement.
 309         @constant kSecCSInternalInformation Return internal code signing information.
 310                 This information is for use by Apple, and is subject to change without notice.
 311                 It will not be further documented here.
 312         @constant kSecCSDynamicInformation Return dynamic validity information about
 313                 the Code. The subject code must be a SecCodeRef (not a SecStaticCodeRef).
 314         @constant kSecCSContentInformation Return more information about the file system
 315                 contents making up the signed code on disk. It is not generally advisable to
 316                 make use of this information, but some utilities (such as software-update
 317                 tools) may find it useful.
 318
 319         Dictionary keys:
 320
 321         @constant kSecCodeInfoCertificates A CFArray of SecCertificates identifying the
 322                 certificate chain of the signing certificate as seen by the system. Absent
 323                 for ad-hoc signed code. May be partial or absent in error cases.
 324         @constant kSecCodeInfoChangedFiles A CFArray of CFURLs identifying all files in
 325                 the code that may have been modified by the process of signing it. (In other
 326                 words, files not in this list will not have been touched by the signing operation.)
 327         @constant kSecCodeInfoCMS A CFData containing the CMS cryptographic object that
 328                 secures the code signature. Empty for ad-hoc signed code.
 329         @constant kSecCodeInfoDesignatedRequirement A SecRequirement describing the
 330                 actual Designated Requirement of the code.
 331         @constant kSecCodeInfoEntitlements A CFData containing the embedded entitlement
 332                 blob of the code, if any.
 333         @constant kSecCodeInfoEntitlementsDict A CFDictionary containing the embedded entitlements
 334                 of the code if it has entitlements and they are in standard dictionary form.
 335                 Absent if the code has no entitlements, or they are in a different format (in which
 336                 case, see kSecCodeInfoEntitlements).
 337         @constant kSecCodeInfoFlags A CFNumber with the static (on-disk) state of the object.
 338                 Contants are defined by the type SecCodeSignatureFlags.
 339         @constant kSecCodeInfoFormat A CFString characterizing the type and format of
 340                 the code. Suitable for display to a (knowledeable) user.
 341         @constant kSecCodeInfoDigestAlgorithm A CFNumber indicating the kind of cryptographic
 342                 hash function used within the signature to seal its pieces together.
 343         @constant kSecCodeInfoIdentifier A CFString with the actual signing identifier
 344                 sealed into the signature. Absent for unsigned code.
 345         @constant kSecCodeInfoImplicitDesignatedRequirement A SecRequirement describing
 346                 the designated requirement that the system did generate, or would have generated,
 347                 for the code. If the Designated Requirement was implicitly generated, this is
 348                 the same object as kSecCodeInfoDesignatedRequirement; this can be used to test
 349                 for an explicit Designated Requirement.
 350         @constant kSecCodeInfoMainExecutable A CFURL identifying the main executable file
 351                 of the code. For single files, that is the file itself. For bundles, it is the
 352                 main executable as identified by its Info.plist.
 353         @constant kSecCodeInfoPList A retained CFDictionary referring to the secured Info.plist
 354                 as seen by code signing. Absent if no Info.plist is known to the code signing
 355                 subsystem. Note that this is not the same dictionary as the one CFBundle would
 356                 give you (CFBundle is free to add entries to the on-disk plist).
 357         @constant kSecCodeInfoRequirements A CFString describing the internal requirements
 358                 of the code in canonical syntax.
 359         @constant kSecCodeInfoRequirementsData A CFData containing the internal requirements
 360                 of the code as a binary blob.
 361         @constant kSecCodeInfoSource A CFString describing the source of the code signature
 362                 used for the code object. The values are meant to be shown in informational
 363                 displays; do not rely on the precise value returned.
 364         @constant kSecCodeInfoStatus A CFNumber containing the dynamic status word of the
 365                 (running) code. This is a snapshot at the time the API is executed and may be
 366                 out of date by the time you examine it. Do note however that most of the bits
 367                 are sticky and thus some values are permanently reliable. Be careful.
 368         @constant kSecCodeInfoTime A CFDate describing the signing date (securely) embedded
 369                 in the code signature. Note that a signer is able to omit this date or pre-date
 370                 it. Nobody certifies that this was really the date the code was signed; however,
 371                 you do know that this is the date the signer wanted you to see.
 372                 Ad-hoc signatures have no CMS and thus never have secured signing dates.
 373         @constant kSecCodeInfoTimestamp A CFDate describing the signing date as (securely)
 374                 certified by a timestamp authority service. This time cannot be falsified by the
 375                 signer; you trust the timestamp authority's word on this.
 376                 Ad-hoc signatures have no CMS and thus never have secured signing dates.
 377         @constant kSecCodeInfoTrust The (retained) SecTrust object the system uses to
 378                 evaluate the validity of the code's signature. You may use the SecTrust API
 379                 to extract detailed information, particularly for reasons why certificate
 380                 validation may have failed. This object may continue to be used for further
 381                 evaluations of this code; if you make any changes to it, behavior is undefined.
 382         @constant kSecCodeInfoUnique A CFData binary identifier that uniquely identifies
 383                 the static code in question. It can be used to recognize this particular code
 384                 (and none other) now or in the future. Compare to kSecCodeInfoIdentifier, which
 385                 remains stable across (developer-approved) updates.
 386                 This is currently the SHA-1 hash of the code's CodeDirectory. However, future
 387                 versions of the system may use a different algorithm for newly signed code.
 388                 Already-signed code not change the reported value in this case.
 389  */
 390 enum {
 391         kSecCSInternalInformation = 1 << 0,
 392         kSecCSSigningInformation = 1 << 1,
 393         kSecCSRequirementInformation = 1 << 2,
 394         kSecCSDynamicInformation = 1 << 3,
 395         kSecCSContentInformation = 1 << 4
 396 };
 397
 398                                                                                                         /* flag required to get this value */
 399 extern const CFStringRef kSecCodeInfoCertificates;      /* Signing */
 400 extern const CFStringRef kSecCodeInfoChangedFiles;      /* Content */
 401 extern const CFStringRef kSecCodeInfoCMS;                       /* Signing */
 402 extern const CFStringRef kSecCodeInfoDesignatedRequirement; /* Requirement */
 403 extern const CFStringRef kSecCodeInfoEntitlements;      /* Requirement */
 404 extern const CFStringRef kSecCodeInfoEntitlementsDict; /* Requirement */
 405 extern const CFStringRef kSecCodeInfoFlags;             /* generic */
 406 extern const CFStringRef kSecCodeInfoFormat;            /* generic */
 407 extern const CFStringRef kSecCodeInfoDigestAlgorithm; /* generic */
 408 extern const CFStringRef kSecCodeInfoIdentifier;        /* generic */
 409 extern const CFStringRef kSecCodeInfoImplicitDesignatedRequirement; /* Requirement */
 410 extern const CFStringRef kSecCodeInfoMainExecutable; /* generic */
 411 extern const CFStringRef kSecCodeInfoPList;                     /* generic */
 412 extern const CFStringRef kSecCodeInfoRequirements;      /* Requirement */
 413 extern const CFStringRef kSecCodeInfoRequirementData; /* Requirement */
 414 extern const CFStringRef kSecCodeInfoSource;            /* generic */
 415 extern const CFStringRef kSecCodeInfoStatus;            /* Dynamic */
 416 extern const CFStringRef kSecCodeInfoTime;                      /* Signing */
 417 extern const CFStringRef kSecCodeInfoTimestamp;         /* Signing */
 418 extern const CFStringRef kSecCodeInfoTrust;                     /* Signing */
 419 extern const CFStringRef kSecCodeInfoUnique;            /* generic */
 420
 421 OSStatus SecCodeCopySigningInformation(SecStaticCodeRef code, SecCSFlags flags,
 422         CFDictionaryRef *information);
 423
 424
 425 /*
 426         @function SecCodeMapMemory
 427         For a given Code or StaticCode object, ask the kernel to accept the signing information
 428         currently attached to it in the caller and use it to validate memory page-ins against it,
 429         updating dynamic validity state accordingly. This change affects all processes that have
 430         the main executable of this code mapped.
 431
 432         @param code A Code or StaticCode object representing the signed code whose main executable
 433                 should be subject to page-in validation.
 434         @param flags Optional flags. Pass kSecCSDefaultFlags for standard behavior.
 435  */
 436 OSStatus SecCodeMapMemory(SecStaticCodeRef code, SecCSFlags flags);
 437
 438
 439 #ifdef __cplusplus
 440 }
 441 #endif
 442
 443 #endif //_H_SECCODE