libsecurity_keychain/lib/SecKeyPriv.h

   1 /*
   2  * Copyright (c) 2002-2009 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  * SecKeyPriv.h - SPIs to SecKeyRef objects.
  24  */
  25
  26 /*!
  27         @header SecKeyPriv
  28         The functions provided in SecKeyPriv.h implement and manage a particular
  29     type of keychain item that represents a key.  A key can be stored in a
  30     keychain, but a key can also be a transient object.
  31
  32         You can use a key as a keychain item in most functions.
  33 */
  34
  35 #ifndef _SECURITY_SECKEYPRIV_H_
  36 #define _SECURITY_SECKEYPRIV_H_
  37
  38 #include <Security/SecKey.h>
  39 #include <Security/x509defs.h>
  40 #include <Security/SecAsn1Types.h>
  41 #include <AvailabilityMacros.h>
  42
  43 #if defined(__cplusplus)
  44 extern "C" {
  45 #endif
  46
  47 typedef struct SecRSAPublicKeyParams {
  48     uint8_t             *modulus;                       /* modulus */
  49     CFIndex             modulusLength;
  50     uint8_t             *exponent;                      /* public exponent */
  51     CFIndex             exponentLength;
  52 } SecRSAPublicKeyParams;
  53
  54 typedef uint32_t SecKeyEncoding;
  55 enum {
  56     /* Typically only used for symmetric keys. */
  57     kSecKeyEncodingRaw = 0,
  58
  59     /* RSA keys are DER-encoded according to PKCS1. */
  60     kSecKeyEncodingPkcs1 = 1,
  61
  62     /* RSA keys are DER-encoded according to PKCS1 with Apple Extensions. */
  63     kSecKeyEncodingApplePkcs1 = 2,
  64
  65     /* RSA public key in SecRSAPublicKeyParams format.  keyData is a pointer
  66        to a SecRSAPublicKeyParams and keyDataLength is
  67        sizeof(SecRSAPublicKeyParams). */
  68     kSecKeyEncodingRSAPublicParams = 3,
  69 };
  70
  71 typedef OSStatus (*SecKeyInitMethod)(SecKeyRef, const uint8_t *, CFIndex,
  72     SecKeyEncoding);
  73 typedef void *(*SecKeyCopyMethod)(SecKeyRef);
  74 typedef void  (*SecKeyDestroyMethod)(SecKeyRef);
  75 typedef void  (*SecKeyDeleteMethod)(SecKeyRef);
  76 typedef void  (*SecKeyShowMethod)(SecKeyRef);
  77 typedef OSStatus (*SecKeyRawSignMethod)(SecKeyRef key, SecPadding padding,
  78         const uint8_t *dataToSign, size_t dataToSignLen,
  79         uint8_t *sig, size_t *sigLen);
  80 typedef OSStatus (*SecKeyRawVerifyMethod)(
  81     SecKeyRef key, SecPadding padding, const uint8_t *signedData,
  82     size_t signedDataLen, const uint8_t *sig, size_t sigLen);
  83 typedef OSStatus (*SecKeyEncryptMethod)(SecKeyRef key, SecPadding padding,
  84     const uint8_t *plainText, size_t plainTextLen,
  85         uint8_t *cipherText, size_t *cipherTextLen);
  86 typedef OSStatus (*SecKeyDecryptMethod)(SecKeyRef key, SecPadding padding,
  87     const uint8_t *cipherText, size_t cipherTextLen,
  88     uint8_t *plainText, size_t *plainTextLen);
  89 typedef size_t (*SecKeyBlockSizeMethod)(SecKeyRef key);
  90 typedef CFDictionaryRef (*SecKeyCopyDictionaryMethod)(SecKeyRef key);
  91
  92 typedef struct {
  93     const char *name;
  94     SecKeyInitMethod init;
  95     SecKeyCopyMethod copy;
  96     SecKeyDestroyMethod destroy;
  97     SecKeyDeleteMethod remove;
  98     SecKeyShowMethod show;
  99     SecKeyRawSignMethod rawSign;
 100     SecKeyRawVerifyMethod rawVerify;
 101     SecKeyEncryptMethod encrypt;
 102     SecKeyDecryptMethod decrypt;
 103     SecKeyBlockSizeMethod blockSize;
 104     SecKeyCopyDictionaryMethod copyDictionary;
 105     /* If known, the number of bytes to allocate for the key field in the SecKey struct. */
 106     int extraBytes;
 107 } SecKeyDescriptor;
 108
 109 /*!
 110         @function SecKeyGetAlgorithmID
 111         @abstract Returns a pointer to a CSSM_X509_ALGORITHM_IDENTIFIER structure for the given key.
 112     @param key A key reference.
 113     @param algid On return, a pointer to a CSSM_X509_ALGORITHM_IDENTIFIER structure.
 114         @result A result code.  See "Security Error Codes" (SecBase.h).
 115 */
 116 OSStatus SecKeyGetAlgorithmID(SecKeyRef key, const CSSM_X509_ALGORITHM_IDENTIFIER **algid)
 117         DEPRECATED_IN_MAC_OS_X_VERSION_10_8_AND_LATER;
 118
 119 enum {
 120     kSecNullAlgorithmID = 0,
 121     kSecRSAAlgorithmID = 1,
 122     kSecDSAAlgorithmID = 2,   /* unsupported, just here for reference. */
 123     kSecECDSAAlgorithmID = 3,
 124 };
 125
 126 /*!
 127         @function SecKeyGetAlgorithmId
 128         @abstract Returns an enumerated constant value which identifies the algorithm for the given key.
 129         @param key A key reference.
 130         @result An algorithm identifier.
 131 */
 132 CFIndex SecKeyGetAlgorithmId(SecKeyRef key)
 133         __OSX_AVAILABLE_STARTING(__MAC_10_8, __IPHONE_NA);
 134
 135 /*!
 136         @function SecKeyGetStrengthInBits
 137         @abstract Returns key strength in bits for the given key.
 138     @param key A key reference.
 139     @param algid A pointer to a CSSM_X509_ALGORITHM_IDENTIFIER structure, as returned from a call to SecKeyGetAlgorithmID.
 140     @param strength On return, the key strength in bits.
 141         @result A result code.  See "Security Error Codes" (SecBase.h).
 142 */
 143 OSStatus SecKeyGetStrengthInBits(SecKeyRef key, const CSSM_X509_ALGORITHM_IDENTIFIER *algid, unsigned int *strength);
 144
 145 /*!
 146         @function SecKeyImportPair
 147         @abstract Takes an asymmetric key pair and stores it in the keychain specified by the keychain parameter.
 148         @param keychainRef A reference to the keychain in which to store the private and public key items. Specify NULL for the default keychain.
 149     @param publicCssmKey A CSSM_KEY which is valid for the CSP returned by SecKeychainGetCSPHandle(). This may be a normal key or reference key.
 150     @param privateCssmKey A CSSM_KEY which is valid for the CSP returned by SecKeychainGetCSPHandle(). This may be a normal key or reference key.
 151     @param initialAccess A SecAccess object that determines the initial access rights to the private key. The public key is given an any/any acl by default.
 152     @param publicKey Optional output pointer to the keychain item reference of the imported public key. The caller must call CFRelease on this value if it is returned.
 153     @param privateKey Optional output pointer to the keychain item reference of the imported private key. The caller must call CFRelease on this value if it is returned.
 154         @result A result code.  See "Security Error Codes" (SecBase.h).
 155     @deprecated in 10.5 and later. Use the SecKeychainItemImport function instead; see <Security/SecImportExport.h>
 156 */
 157 OSStatus SecKeyImportPair(
 158         SecKeychainRef keychainRef,
 159                 const CSSM_KEY *publicCssmKey,
 160                 const CSSM_KEY *privateCssmKey,
 161         SecAccessRef initialAccess,
 162         SecKeyRef* publicKey,
 163         SecKeyRef* privateKey)
 164                 DEPRECATED_IN_MAC_OS_X_VERSION_10_5_AND_LATER;
 165
 166 /*!
 167     @function SecKeyCreate
 168     @abstract Create a key reference from the supplied key data.
 169     @param allocator CFAllocator to allocate the key data. Pass NULL to use the default allocator.
 170     @param keyClass A descriptor for the particular class of key that is being created.
 171     @param keyData Data from which to create the key. Specify the format of this data in the encoding parameter.
 172     @param keyDataLength Length of the data pointed to by keyData.
 173     @param encoding A value of type SecKeyEncoding which describes the format of keyData.
 174     @result A key reference.
 175     @discussion Warning: this function is NOT intended for use outside the Security stack in its current state. <rdar://3201885>
 176         IMPORTANT: on Mac OS X 10.5 and earlier, the SecKeyCreate function had a different parameter list.
 177         The current parameter list matches the iPhone OS implementation. Existing clients of this function
 178         on Mac OS X (and there should not be any outside the Security stack, per the warning above) must
 179         migrate to the replacement function, SecKeyCreateWithCSSMKey.
 180 */
 181 SecKeyRef SecKeyCreate(CFAllocatorRef allocator,
 182     const SecKeyDescriptor *keyClass, const uint8_t *keyData,
 183         CFIndex keyDataLength, SecKeyEncoding encoding);
 184
 185 /*!
 186     @function SecKeyCreateWithCSSMKey
 187     @abstract Generate a temporary floating key reference for a CSSM_KEY.
 188     @param key A pointer to a CSSM_KEY structure.
 189     @param keyRef On return, a key reference.
 190     @result A result code. See "Security Error Codes" (SecBase.h).
 191     @discussion Warning: this function is NOT intended for use outside the Security stack in its current state. <rdar://3201885>
 192 */
 193 OSStatus SecKeyCreateWithCSSMKey(const CSSM_KEY *key, SecKeyRef* keyRef);
 194
 195 /*!
 196         @enum Dictionary key constants for SecKeyGeneratePair API.
 197         @discussion Predefined key constants used to get or set values in a dictionary.
 198         @constant kSecPrivateKeyAttrs The value for this key is a CFDictionaryRef
 199          containing attributes specific for the private key to be generated.
 200         @constant kSecPublicKeyAttrs The value for this key is a CFDictionaryRef
 201          containing attributes specific for the public key to be generated.
 202 */
 203 extern CFTypeRef kSecPrivateKeyAttrs;
 204 extern CFTypeRef kSecPublicKeyAttrs;
 205
 206 /*!
 207         @function SecKeyGeneratePair
 208         @abstract Generate a private/public keypair.
 209         @param parameters A dictionary containing one or more key-value pairs.
 210          See the discussion sections below for a complete overview of options.
 211         @param publicKey On return, a SecKeyRef reference to the public key.
 212         @param privateKey On return, a SecKeyRef reference to the private key.
 213         @result A result code. See "Security Error Codes" (SecBase.h).
 214         @discussion In order to generate a keypair the parameters dictionary must
 215          at least contain the following keys:
 216
 217          * kSecAttrKeyType with a value being kSecAttrKeyTypeRSA or any other
 218          kSecAttrKeyType defined in SecItem.h
 219          * kSecAttrKeySizeInBits with a value being a CFNumberRef or CFStringRef
 220          containing the requested key size in bits.  Example sizes for RSA
 221          keys are: 512, 768, 1024, 2048.
 222
 223          The values below may be set either in the top-level dictionary or in a
 224          dictionary that is the value of the kSecPrivateKeyAttrs or
 225          kSecPublicKeyAttrs key in the top-level dictionary.  Setting these
 226          attributes explicitly will override the defaults below.  See SecItem.h
 227          for detailed information on these attributes including the types of
 228          the values.
 229
 230          * kSecAttrLabel default NULL
 231          * kSecAttrIsPermanent if this key is present and has a Boolean
 232          value of true, the key or key pair will be added to the default
 233          keychain.
 234          * kSecAttrApplicationTag default NULL
 235          * kSecAttrEffectiveKeySize default NULL same as kSecAttrKeySizeInBits
 236          * kSecAttrCanEncrypt default false for private keys, true for public keys
 237          * kSecAttrCanDecrypt default true for private keys, false for public keys
 238          * kSecAttrCanDerive default true
 239          * kSecAttrCanSign default true for private keys, false for public keys
 240          * kSecAttrCanVerify default false for private keys, true for public keys
 241          * kSecAttrCanWrap default false for private keys, true for public keys
 242          * kSecAttrCanUnwrap default true for private keys, false for public keys
 243
 244 */
 245 OSStatus SecKeyGeneratePair(CFDictionaryRef parameters,
 246                                                         SecKeyRef *publicKey, SecKeyRef *privateKey);
 247
 248
 249 /*!
 250         @function SecKeyRawSign
 251         @abstract Given a private key and data to sign, generate a digital signature.
 252         @param key Private key with which to sign.
 253         @param padding See Padding Types above, typically kSecPaddingPKCS1SHA1.
 254         @param dataToSign The data to be signed, typically the digest of the actual data.
 255         @param dataToSignLen Length of dataToSign in bytes.
 256         @param sig Pointer to buffer in which the signature will be returned.
 257         @param sigLen IN/OUT maximum length of sig buffer on input, actualy length of sig on output.
 258         @result A result code. See "Security Error Codes" (SecBase.h).
 259         @discussion If the padding argument is kSecPaddingPKCS1, PKCS1 padding
 260          will be performed prior to signing. If this argument is kSecPaddingNone,
 261          the incoming data will be signed "as is".
 262
 263          When PKCS1 padding is performed, the maximum length of data that can
 264          be signed is the value returned by SecKeyGetBlockSize() - 11.
 265
 266          NOTE: The behavior this function with kSecPaddingNone is undefined if the
 267          first byte of dataToSign is zero; there is no way to verify leading zeroes
 268          as they are discarded during the calculation.
 269
 270          If you want to generate a proper PKCS1 style signature with DER encoding of
 271          the digest type - and the dataToSign is a SHA1 digest - use kSecPaddingPKCS1SHA1.
 272 */
 273 OSStatus SecKeyRawSign(
 274                 SecKeyRef           key,
 275                 SecPadding          padding,
 276                 const uint8_t       *dataToSign,
 277                 size_t              dataToSignLen,
 278                 uint8_t             *sig,
 279                 size_t              *sigLen);
 280
 281
 282 /*!
 283         @function SecKeyRawVerify
 284         @abstract Given a public key, data which has been signed, and a signature, verify the signature.
 285         @param key Public key with which to verify the signature.
 286         @param padding See Padding Types above, typically kSecPaddingPKCS1SHA1.
 287         @param signedData The data over which sig is being verified, typically the digest of the actual data.
 288         @param signedDataLen Length of signedData in bytes.
 289         @param sig Pointer to the signature to verify.
 290         @param sigLen Length of sig in  bytes.
 291         @result A result code. See "Security Error Codes" (SecBase.h).
 292         @discussion If the padding argument is kSecPaddingPKCS1, PKCS1 padding
 293          will be checked during verification. If this argument is kSecPaddingNone,
 294          the incoming data will be compared directly to sig.
 295
 296          If you are verifying a proper PKCS1-style signature, with DER encoding of the digest
 297          type - and the signedData is a SHA1 digest - use kSecPaddingPKCS1SHA1.
 298 */
 299 OSStatus SecKeyRawVerify(
 300                  SecKeyRef           key,
 301                  SecPadding          padding,
 302                  const uint8_t       *signedData,
 303                  size_t              signedDataLen,
 304                  const uint8_t       *sig,
 305                  size_t              sigLen);
 306
 307
 308 /*!
 309         @function SecKeyEncrypt
 310         @abstract Encrypt a block of plaintext.
 311         @param key Public key with which to encrypt the data.
 312         @param padding See Padding Types above, typically kSecPaddingPKCS1.
 313         @param plainText The data to encrypt.
 314         @param plainTextLen Length of plainText in bytes, this must be less
 315          or equal to the value returned by SecKeyGetBlockSize().
 316         @param cipherText Pointer to the output buffer.
 317         @param cipherTextLen On input, specifies how much space is available at
 318          cipherText; on return, it is the actual number of cipherText bytes written.
 319         @result A result code. See "Security Error Codes" (SecBase.h).
 320         @discussion If the padding argument is kSecPaddingPKCS1, PKCS1 padding
 321          will be performed prior to encryption. If this argument is kSecPaddingNone,
 322          the incoming data will be encrypted "as is".
 323
 324          When PKCS1 padding is performed, the maximum length of data that can
 325          be encrypted is the value returned by SecKeyGetBlockSize() - 11.
 326
 327          When memory usage is a critical issue, note that the input buffer
 328          (plainText) can be the same as the output buffer (cipherText).
 329 */
 330 OSStatus SecKeyEncrypt(
 331            SecKeyRef           key,
 332            SecPadding          padding,
 333            const uint8_t       *plainText,
 334            size_t              plainTextLen,
 335            uint8_t             *cipherText,
 336            size_t              *cipherTextLen);
 337
 338
 339 /*!
 340         @function SecKeyDecrypt
 341         @abstract Decrypt a block of ciphertext.
 342         @param key Private key with which to decrypt the data.
 343         @param padding See SecPadding types above; typically kSecPaddingPKCS1.
 344         @param cipherText The data to decrypt.
 345         @param cipherTextLen Length of cipherText in bytes; this must be less
 346          or equal to the value returned by SecKeyGetBlockSize().
 347         @param plainText Pointer to the output buffer.
 348         @param plainTextLen On input, specifies how much space is available at
 349          plainText; on return, it is the actual number of plainText bytes written.
 350         @result A result code. See "Security Error Codes" (SecBase.h).
 351         @discussion If the padding argument is kSecPaddingPKCS1, PKCS1 padding
 352          will be removed after decryption. If this argument is kSecPaddingNone,
 353          the decrypted data will be returned "as is".
 354
 355          When memory usage is a critical issue, note that the input buffer
 356          (plainText) can be the same as the output buffer (cipherText).
 357 */
 358 OSStatus SecKeyDecrypt(
 359            SecKeyRef           key,             /* Private key */
 360            SecPadding          padding,                 /* kSecPaddingNone, kSecPaddingPKCS1, kSecPaddingOAEP */
 361            const uint8_t       *cipherText,
 362            size_t              cipherTextLen,   /* length of cipherText */
 363            uint8_t             *plainText,
 364            size_t              *plainTextLen);  /* IN/OUT */
 365
 366 OSStatus SecKeyVerifyDigest(
 367            SecKeyRef           key,            /* Private key */
 368            const SecAsn1AlgId  *algId,         /* algorithm oid/params */
 369            const uint8_t       *digestData,        /* signature over this digest */
 370            size_t              digestDataLen,  /* length of dataToDigest */
 371            const uint8_t       *sig,           /* signature to verify */
 372            size_t              sigLen);        /* length of sig */
 373
 374 OSStatus SecKeySignDigest(
 375            SecKeyRef           key,            /* Private key */
 376            const SecAsn1AlgId  *algId,         /* algorithm oid/params */
 377            const uint8_t       *digestData,    /* signature over this digest */
 378            size_t              digestDataLen,  /* length of digestData */
 379            uint8_t             *sig,           /* signature, RETURNED */
 380            size_t              *sigLen);       /* IN/OUT */
 381
 382
 383 /* These are the named curves we support. These values come from RFC 4492
 384  section 5.1.1, with the exception of SSL_Curve_None which means
 385  "ECDSA not negotiated". */
 386 typedef enum
 387 {
 388         kSecECCurveNone = -1,
 389         kSecECCurveSecp256r1 = 23,
 390         kSecECCurveSecp384r1 = 24,
 391         kSecECCurveSecp521r1 = 25
 392 } SecECNamedCurve;
 393
 394 /* Return a named curve enum for ecPrivateKey. */
 395 SecECNamedCurve SecECKeyGetNamedCurve(SecKeyRef ecPrivateKey);
 396 CFDataRef SecECKeyCopyPublicBits(SecKeyRef key);
 397
 398 /* Given an RSA public key in encoded form return a SecKeyRef representing
 399    that key. Supported encodings are kSecKeyEncodingPkcs1. */
 400 SecKeyRef SecKeyCreateRSAPublicKey(CFAllocatorRef allocator,
 401                                    const uint8_t *keyData, CFIndex keyDataLength,
 402                                    SecKeyEncoding encoding);
 403
 404 CFDataRef SecKeyCopyModulus(SecKeyRef rsaPublicKey);
 405 CFDataRef SecKeyCopyExponent(SecKeyRef rsaPublicKey);
 406
 407 /*!
 408  @function SecKeyCopyPublicBytes
 409  @abstract Gets the bits of a public key
 410  @param key Key to retrieve the bits.
 411  @param publicBytes An out parameter to receive the public key bits
 412  @result Errors if any when retrieving the public key bits..
 413  */
 414 OSStatus SecKeyCopyPublicBytes(SecKeyRef key, CFDataRef* publicBytes);
 415
 416 /*!
 417         @function SecKeyCreatePublicFromPrivate
 418         @abstract Create a public SecKeyRef from a private SecKeyRef
 419         @param privateKey The private SecKeyRef for which you want the public key
 420         @result A public SecKeyRef, or NULL if the conversion failed
 421         @discussion This is a "best attempt" function, hence the SPI nature. If the public
 422     key bits are not in memory, it attempts to load from the keychain. If the public
 423     key was not tracked on the keychain, it will fail.
 424 */
 425 SecKeyRef SecKeyCreatePublicFromPrivate(SecKeyRef privateKey);
 426
 427 /*!
 428         @function SecKeyCreateFromPublicData
 429 */
 430 SecKeyRef SecKeyCreateFromPublicData(CFAllocatorRef allocator, CFIndex algorithmID, CFDataRef publicBytes);
 431
 432 OSStatus SecKeyRawVerifyOSX(
 433                  SecKeyRef           key,
 434                  SecPadding          padding,
 435                  const uint8_t       *signedData,
 436                  size_t              signedDataLen,
 437                  const uint8_t       *sig,
 438                  size_t              sigLen);
 439
 440 #if defined(__cplusplus)
 441 }
 442 #endif
 443
 444 #endif /* !_SECURITY_SECKEYPRIV_H_ */
 445