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codesign(1)               BSD General Commands Manual              codesign(1)


NAME

     codesign -- Create and manipulate code signatures


SYNOPSIS

     codesign -s identity [-i identifier] [-r requirements] [-fv] [path ...]
     codesign -v [-R requirement] [-v] [path|pid ...]
     codesign -d [-v] [path|pid ...]
     codesign -h [-v] [pid ...]


DESCRIPTION

     The codesign command is used to create, check, and display code signa-
     tures, as well as inquire into the dynamic status of signed code in the
     system.

     codesign requires exactly one operation option to determine what action
     is to be performed, as well as any number of other options to modify its
     behavior. It can act on any number of objects per invocation, but per-
     forms the same operation on all of them.

     codesign accepts single-character (classic) options, as well as GNU-style
     long options of the form --name and --name=value. Common options have
     both forms; less frequent and specialized options have only long form.
     Note that the form --name value (without equal sign) will not work as
     expected on options with optional values.


OPTIONS

     The options are as follows:

     --all-architectures
             When verifying a code signature on code that has a universal
             ("fat") Mach-O binary, separately verify each architecture con-
             tained. This is the default unless overridden with the -a
             (--architecture) option.

     -a, --architecture architecture
             When verifying or displaying signatures, explicitly select the
             Mach-O architecture given. The architecture can be specified
             either by name (e.g. i386) or by number; if by number, a sub-
             architecture may be appended separated by a comma.  This option
             applies only to Mach-O binary code and is ignored for other
             types.  If the path uses the Mach-O format and contains no code
             of the given architecture, the command will fail.  The default
             for verification is --all-architectures, to verify all architec-
             tures present.  The default for display is to report on the
             native architecture of the host system.  When signing, codesign
             will always sign all architectures contained in a universal Mach-
             O file.

     --bundle-version version-string
             When handling versioned bundles such as frameworks, explicitly
             specify the version to operate on. This must be one of the names
             in the "Versions" directory of the bundle.  If not specified,
             codesign uses the bundle's default version.  Note that most
             frameworks delivered with the system have only one version, and
             thus this option is irrelevant for them.  There is currently no
             facility for operating on all versions of a bundle at once.

     -d, --display
             Display information about the code at the path(s) given. Increas-
             ing levels of verbosity produce more output.  The format is
             designed to be moderately easy to parse by simple scripts while
             still making sense to human eyes.  In addition, the -r, --file-
             list, --extract-certificates, and --entitlements options can be
             used to retrieve additional information.

     -D, --detached filename
             When signing, designates that a detached signature should be
             written to the specified file. The code being signed is not modi-
             fied and need not be writable.  When verifying, designates a file
             containing a detached signature to be used for verification. Any
             embedded signature in the code is ignored.

     --deep  When signing a bundle, specifies that nested code content such as
             helpers, frameworks, and plug-ins, should be recursively signed
             in turn. Beware that all signing options you specify will apply,
             in turn, to such nested content.
             When verifying a bundle, specifies that any nested code content
             will be recursively verified as to its full content. By default,
             verification of nested content is limited to a shallow investiga-
             tion that may not detect changes to the nested code.
             When displaying a signature, specifies that a list of directly
             nested code should be written to the display output. This lists
             only code directly nested within the subject; anything nested
             indirectly will require recursive application of the codesign
             command.

     --detached-database
             When signing, specifies that a detached signature should be gen-
             erated as with the --detached option, but that the resulting sig-
             nature should be written into a system database, from where it is
             made automatically available whenever apparently unsigned code is
             validated on the system.
             Writing to this system database requires elevated process privi-
             leges that are not available to ordinary users.

     -f, --force
             When signing, causes codesign to replace any existing signature
             on the path(s) given. Without this option, existing signatures
             will not be replaced, and the signing operation fails.

     -h, --hosting
             Constructs and prints the hosting chain of a running program. The
             pid arguments must denote running code (pids etc.) With verbose
             options, this also displays the individual dynamic validity sta-
             tus of each element of the hosting chain.

     -i, --identifier identifier
             During signing, explicitly specify the unique identifier string
             that is embedded in code signatures. If this option is omitted,
             the identifier is derived from either the Info.plist (if
             present), or the filename of the executable being signed, possi-
             bly modified by the --prefix option.  It is a very bad idea to
             sign different programs with the same identifier.

     -o, --options flag,...
             During signing, specifies a set of option flags to be embedded in
             the code signature. The value takes the form of a comma-separated
             list of names (with no spaces). Alternatively, a numeric value
             can be used to directly specify the option mask (CodeDirectory
             flag word). See OPTION FLAGS below.

     -P, --pagesize pagesize
             Indicates the granularity of code signing. Pagesize must be a
             power of two.  Chunks of pagesize bytes are separately signed and
             can thus be independently verified as needed.  As a special case,
             a pagesize of zero indicates that the entire code should be
             signed and verified as a single, possibly gigantic page. This
             option only applies to the main executable and has no effect on
             the sealing of associated data, including resources.

     -r, --requirements requirements
             During signing, indicates that internal requirements should be
             embedded in the code path(s) as specified. See "specifying
             requirements" below.  Defaults will be applied to requirement
             types that are not explicitly specified; if you want to defeat
             such a default, specify "never" for that type.
             During display, indicates where to write the code's internal
             requirements. Use -r- to write them to standard output.

     -R, --test-requirement requirement
             During verification, indicates that the path(s) given should be
             verified against the code requirement specified. If this option
             is omitted, the code is verified only for internal integrity and
             against its own designated requirement.

     -s, --sign identity
             Sign the code at the path(s) given using this identity. See SIGN-
             ING IDENTITIES below.

     -v, --verbose
             Sets (with a numeric value) or increments the verbosity level of
             output. Without the verbose option, no output is produced upon
             success, in the classic UNIX style.  If no other options request
             a different action, the first -v encountered will be interpreted
             as --verify instead (and does not increase verbosity).

     -v, --verify
             Requests verification of code signatures.  If other actions
             (sign, display, etc.) are also requested, -v is interpreted to
             mean --verbose.

     --continue
             Instructs codesign to continue processing path arguments even if
             processing one fails.  If this option is given, exit due to oper-
             ational errors is deferred until all path arguments have been
             considered. The exit code will then indicate the most severe
             failure (or, with equal severity, the first such failure encoun-
             tered).

     --dryrun
             During signing, performs almost all signing operations, but does
             not actually write the result anywhere. Cryptographic signatures
             are still generated, actually using the given signing identity
             and triggering any access control checks normally, though the
             resulting signature is then discarded.

     --entitlements path
             When signing, take the file at the given path and embed its con-
             tents in the signature as entitlement data. If the data at path
             does not already begin with a suitable binary ("blob") header,
             one is attached automatically.
             When displaying a signature, extract any entitlement data from
             the signature and write it to the path given. Use "-" to write to
             standard output.  By default, the binary "blob" header is
             returned intact; prefix the path with a colon ":" to automati-
             cally strip it off.  If the signature has no entitlement data,
             nothing is written (this is not an error).

     --extract-certificates prefix
             When displaying a signature, extract the certificates in the
             embedded certificate chain and write them to individual files.
             The prefix argument is appended with numbers 0, 1, ... to form
             the filenames, which can be relative or absolute. Certificate 0
             is the leaf (signing) certificate, and as many files are written
             as there are certificates in the signature. The files are in
             ASN.1 (DER) form.  If prefix is omitted, the default prefix is
             "codesign" in the current directory.

     --file-list path
             When signing or displaying a signature, codesign writes to the
             given path a list of files that may have been modified as part of
             the signing process. This is useful for installer or patcher pro-
             grams that need to know what was changed or what files are needed
             to make up the "signature" of a program. The file given is
             appended-to, with one line per absolute path written. An argument
             of "-" (single dash) denotes standard output.  Note that the list
             may be somewhat pessimistic - all files not listed are guaranteed
             to be unchanged by the signing process, but some of the listed
             files may not actually have changed.  Also note that changes may
             have been made to extended attributes of these files.

     --ignore-resources
             During static validation, do not validate the contents of the
             code's resources.  In effect, this will pass validation on code
             whose resources have been corrupted (or inappropriately signed).
             On large programs, it will also substantially speed up static
             validation, since all the resources will not be read into memory.
             Obviously, the outcome of such a validation should be considered
             on its merits.

     --keychain filename
             During signing, only search for the signing identity in the key-
             chain file specified. This can be used to break any matching ties
             if you have multiple similarly-named identities in several key-
             chains on the user's search list.  Note that the standard key-
             chain search path is still consulted while constructing the cer-
             tificate chain being embedded in the signature.
             Note that filename will not be searched to resolve the signing
             identity's certificate chain unless it is also on the user's key-
             chain search list.

     --prefix string
             If no explicit unique identifier is specified (using the -i
             option), and if the implicitly generated identifier does not con-
             tain any dot (.) characters, then the given string is prefixed to
             the identifier before use. If the implicit identifier contains a
             dot, it is used as-is. Typically, this is used to deal with com-
             mand tools without Info.plists, whose default identifier is sim-
             ply the command's filename; the conventional prefix used is
             com.domain. (note that the final dot needs to be explicit).

     --preserve-metadata=list
             When re-signing code that is already signed, reuse some informa-
             tion from the old signature.  If new data is specified explic-
             itly, it is preferred.  You still need to specify the -f
             (--force) option to enable overwriting signatures at all.  If
             this option is absent, any old signature has no effect on the
             signing process.
             This option takes a comma-separated list of names, which you may
             reasonably abbreviate:

             identifier      Preserve the signing identifier (--identifier)
                             instead of generating a default identifier.

             entitlements    Preserve the entitlement data (--entitlements).

             resource-rules  Preserve and reuse the resource rules
                             (--resource-rules).

             requirements    Preserve the internal requirements (--require-
                             ments option), including any explicit Designated
                             Requirement. Note that all internal requirements
                             are preserved or regenerated as a whole; you can-
                             not pick and choose individual elements with this
                             option.
             For historical reasons, this option can be given without a value,
             which preserves all of these values as presently known. This use
             is deprecated and will eventually be removed; always specify an
             explicit list of preserved items.

     --resource-rules filename
             During signing, this option overrides the default rules for iden-
             tifying and collecting bundle resources and nested code to be
             sealed into the signature. The argument is the path to a property
             list (plist) file containing scanning and qualification instruc-
             tions. See the code signing documentation for details.

     --timestamp [=URL]
             During signing, requests that a timestamp authority server be
             contacted to authenticate the time of signing. The server con-
             tacted is given by the URL value.  If this option is given with-
             out a value, a default server provided by Apple is used.  Note
             that this server may not support signatures made with identities
             not furnished by Apple.  If the timestamp authority service can-
             not be contacted over the Internet, or it malfunctions or refuses
             service, the signing operation will fail.
             If this option is not given at all, a system-specific default
             behavior is invoked.  This may result in some but not all code
             signatures being timestamped.
             The special value none explicitly disables the use of timestamp
             services.


OPERATION

     In the first synopsis form, codesign attempts to sign the code objects at
     the path(s) given, using the identity provided. Internal requirements and
     entitlements are embedded if requested. Internal requirements not speci-
     fied may be assigned suitable default values. Defaulting applies sepa-
     rately to each type of internal requirement.  If an identifier is explic-
     itly given, it is sealed into all path(s).  Otherwise, each path derives
     its identifier independently from its Info.plist or pathname.  Code
     nested within bundle directories (as identified from the applicable
     Resource Rules) must already be signed or the signing operation will
     fail, unless the --deep option is given, in which case any unsigned
     nested code will be recursively signed before proceeding, using the same
     signing options and parameters. If the --force option is given, any
     existing top-level signature is replaced, subject to any
     --preserve-metadata options also present. Combining the --force and
     --deep options results in forcible replacement of all signatures within
     the target bundle, as long as the resource rules identify them.

     In the second synopsis form, codesign verifies the code signatures on all
     the path(s) given. The verification confirms that the code at those
     path(s) is signed, that the signature is valid, and that all sealed com-
     ponents are unaltered. If a requirement is given, each path is also
     checked against this requirement (but see DIAGNOSTICS below).  If verbose
     verification is requested, the program is also checked against its own
     designated requirement, which should never fail for a properly signed
     program.

     If a path begins with a decimal digit, it is interpreted as the process
     id of a running process in the system, and dynamic validation is per-
     formed on that process instead.  This checks the code's dynamic status
     and just enough static data to close the nominal security envelope. Add
     at least one level of verbosity to also perform a full static check.

     In the third synopsis form, codesign displays the contents of the signa-
     tures on the path(s) given. More information is displayed as the ver-
     bosity level increases.  This form may not completely verify the signa-
     tures on the path(s); though it may perform some verification steps in
     the process of obtaining information about the path(s).  If the -r path
     option is given, internal requirements will be extracted from the path(s)
     and written to path; specify a dash "-" to write to standard output. If
     the code does not contain an explicit designated requirement, the implied
     one will be retrieved and written out as a source comment.  If the
     --entitlements path option is given, embedded entitlement data will be
     extracted likewise and written to the file specified.

     In the fourth synopsis form, codesign constructs the hosting path for
     each pid given and writes it, one host per line, to standard output. The
     hosting path is the chain of code signing hosts starting with the most
     specific code known to be running, and ending with the root of trust (the
     kernel). If the --verbose option is given, the dynamic validity status of
     each host is also displayed, separated from the path by a tab character.
     Note that hosting chains can at times be constructed for invalid or even
     unsigned code, and the output of this form of the codesign command should
     not be taken as a statement of formal code validity. Only codesign
     --verify can do that; and in fact, formal verification constructs the
     hosting chain as part of its operation (but does not display it).


SIGNING IDENTITIES

     To be used for code signing, a digital identity must be stored in a key-
     chain that is on the calling user's keychain search list.  All keychain
     sources are supported if properly configured. In particular, it is possi-
     ble to sign code with an identity stored on a supported smart card.  If
     your signing identity is stored in a different form, you need to make it
     available in keychain form to sign code with it.
     If the --keychain argument is used, identity is only looked-for in the
     specific keychain given. This is meant to help disambiguate references to
     identities.  Even in that case, the full keychain search list is still
     consulted for additional certificates needed to complete the signature.

     The identity is first considered as the full name of a keychain identity
     preference.  If such a preference exists, it directly names the identity
     used.  Otherwise, the identity is located by searching all keychains for
     a certificate whose subject common name (only) contains the identity
     string given. If there are multiple matches, the operation fails and no
     signing is performed; however, an exact match is preferred over a partial
     match.  These comparisons are case sensitive.  Multiple instances of the
     exactly same certificate in multiple keychains are tolerated as harmless.

     If identity consists of exactly forty hexadecimal digits, it is instead
     interpreted as the SHA-1 hash of the certificate part of the desired
     identity.  In this case, the identity's subject name is not considered.

     Both identity preferences and certificate hashes can be used to identify
     a particular signing identity regardless of name. Identity preferences
     are global settings for each user and provide a layer of indirection.
     Certificate hashes are very explicit and local. These choices, combined
     with what is placed into Xcode project and target build variables and/or
     script settings, allows for very flexible designation of signing identi-
     ties.

     If identity is the single letter "-" (dash), ad-hoc signing is performed.
     Ad-hoc signing does not use an identity at all, and identifies exactly
     one instance of code. Significant restrictions apply to the use of ad-hoc
     signed code; consult documentation before using this.

     codesign will attempt to embed the entire certificate chain documenting
     the signing identity in the code signature it generates, including any
     intermediate certificates and the anchor certificate. It looks for those
     in the keychain search list of the user performing the signing operation.
     If it cannot generate the entire certificate chain, signing may still
     succeed, but verification may fail if the verifying code does not have an
     independent source for the missing certificates (from its keychains).


SPECIFYING REQUIREMENTS

     The requirement(s) arguments (-r and -R) can be given in various forms. A
     plain text argument is taken to be a path to a file containing the
     requirement(s).  codesign will accept both binary files containing prop-
     erly compiled requirements code, and source files that are automatically
     compiled before use.  An argument of "-" requests that the requirement(s)
     are read from standard input.  Finally, an argument that begins with an
     equal sign "=" is taken as a literal requirements source text, and is
     compiled accordingly for use.


OPTION FLAGS

     When signing, a set of option flags can be specified to change the behav-
     ior of the system when using the signed code. The following flags are
     recognized by codesign; other flags may exist at the API level. Note that
     you can specify any valid flags by giving a (single) numeric value
     instead of a list of option names.

     kill     Forces the signed code's kill flag to be set when the code
              begins execution.  Code with the kill flag set will die when it
              becomes dynamically invalid. It is therefore safe to assume that
              code marked this way, once validated, will have continue to have
              a valid identity while alive.

     hard     Forces the signed code's hard flag to be set when the code
              begins execution.  The hard flag is a hint to the system that
              the code prefers to be denied access to resources if gaining
              such access would invalidate its identity.

     host     Marks the code as capable of hosting guest code. You must set
              this option if you want the code to act as a code signing host,
              controlling subsidiary ("guest") code. This flag is set automat-
              ically if you specify an internal guest requirement.

     expires  Forces any validation of the code to consider expiration of the
              certificates involved. Code signatures generated with this flag
              will fail to verify once any of the certificates in the chain
              has expired, regardless of the intentions of the verifier. Note
              that this flag does not affect any other checks that may cause
              signature validation to fail, including checks for certificate
              revocation.

     Note that code can set the hard and kill flags on itself at any time. The
     signing options only affect their initial state. Once set by any means,
     these flags cannot be cleared for the lifetime of the code. Therefore,
     specifying such flags as signing options guarantees that they will be set
     whenever the signed code runs.

     If the code being signed has an Info.plist that contains a key named
     CSFlags, the value of that key is taken as the default value for the
     options. The value of CSFlags can be a string in the same form as the
     --options option, or an integer number specifying the absolute numeric
     value. Note however that while you can abbreviate flag names on the com-
     mand lines, you must spell them out in the Info.plist.


EXAMPLES

     To sign application Terminal.app with a signing identity named "author-
     ity":
           codesign -s authority Terminal.app

     To sign the command-line tool "helper" with the same identity, overwrit-
     ing any existing signature, using the signing identifier
     "com.mycorp.helper", and embedding a custom designated requirement
           codesign -f -s authority --prefix=com.mycorp. -r="designated =>
           anchor /tmp/foo" helper

     To verify the signature on Terminal.app and produce some verbose output:
           codesign --verify --verbose Terminal.app

     To verify the dynamic validity of process 666:
           codesign --verify 666

     To display all information about Terminal.app's code signature:
           codesign --display --verbose=4 Terminal.app

     To extract the internal requirements from Terminal.app to standard out-
     put:
           codesign --display -r- Terminal.app


DIAGNOSTICS

     codesign exits 0 if all operations succeed. This indicates that all codes
     were signed, or all codes verified properly as requested. If a signing or
     verification operation fails, the exit code is 1. Exit code 2 indicates
     invalid arguments or parameters. Exit code 3 indicates that during veri-
     fication, all path(s) were properly signed but at least one of them
     failed to satisfy the requirement specified with the -R option.

     For verification, all path arguments are always investigated before the
     program exits.  For all other operations, the program exits upon the
     first error encountered, and any further path arguments are ignored,
     unless the --continue option was specified, in which case codesign will
     defer the failure exit until after it has attempted to process all path
     arguments in turn.


SIGNING ATOMICITY

     When a signing operation fails for a particular code, the code may
     already have been modified in certain ways by adding requisite signature
     data. Such information will not change the operation of the code, and the
     code will not be considered signed even with these pieces in place. You
     may repeat the signing operation without difficulty.  Note however that a
     previous valid signature may have been effectively destroyed if you spec-
     ified the -f option.
     If you require atomicity of signing stricter than provided by codesign,
     you need to make an explicit copy of your code and sign that.


ENVIRONMENT

     If the CODESIGN_ALLOCATE environment variable is set, it identifies a
     substitute codesign_allocate tool used to allocate space for code signa-
     tures in Mach-O binaries. This is used by Xcode SDK distributions to pro-
     vide architectural support for non-native platforms such as iPhones.  The
     system will not accept such substitutes unless they are specially signed
     (by Apple).


FILES

     /var/db/DetachedSignatures  System-wide database of detached code signa-
                                 tures for unsigned code.


SEE ALSO

     csreq(1), xcodebuild(1), codesign_allocate(1)


HISTORY

     The codesign command first appeared in Mac OS 10.5.0 (Leopard).


BUGS

     Some options only apply to particular operations, and codesign ignores
     them (without complaining) if you specify them for an operation for which
     they have no meaning.

     The --preserve-metadata option used to take no value, and varied across
     releases in what exactly it preserved. The ensuing confusion is still
     with you if you need to make backward-compatible scripts.

     The dual meaning of the -v option, indicating either verbosity or verifi-
     cation, confuses some people. If you find it confusing, use the unambigu-
     ous long forms --verbose and --verify instead.


NOTES

     The Xcode build system invokes codesign automatically if the
     CODE_SIGN_IDENTITY build variable is set.  You can express any combina-
     tion of codesign options with additional build variables there.

     codesign is fundamentally a shell around the code signing APIs, and per-
     forms nothing of the underlying work.  Replacing it with older or newer
     versions is unlikely to have a useful effect.

     codesign has several operations and options that are purposely left
     undocumented in this manual page because they are either experimental
     (and subject to change at any time), or unadvised to the unwary.  The
     interminably curious are referred to the published source code.

BSD                               May 7, 2011                              BSD

Mac OS X 10.9 - Generated Sat Oct 12 09:37:51 CDT 2013
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