ana*_*oma 6 documentation cryptography ios commoncrypto
我试图为Apple的CommonCrypto库找到某种参考,因为显然Apple没有任何明显的链接,谷歌给出的那些已经过时了,如下所示:
有什么暗示吗?是否有更好的库可用于开发具有大量加密功能的应用程序?
谢谢.
它们提供的大多数信息都在头文件的开始行中。按住命令键盘按钮并抬起单击 CommonCrypto/CommonCryptor.h 来访问它。
/*!
@header CommonCryptor.h
@abstract Generic interface for symmetric encryption.
@discussion This interface provides access to a number of symmetric
encryption algorithms. Symmetric encryption algorithms come
in two "flavors" - block ciphers, and stream ciphers. Block
ciphers process data (while both encrypting and decrypting)
in discrete chunks of data called blocks; stream ciphers
operate on arbitrary sized data.
The object declared in this interface, CCCryptor, provides
access to both block ciphers and stream ciphers with the same
API; however some options are available for block ciphers that
do not apply to stream ciphers.
The general operation of a CCCryptor is: initialize it
with raw key data and other optional fields with
CCCryptorCreate(); process input data via one or more calls to
CCCryptorUpdate(), each of which may result in output data
being written to caller-supplied memory; and obtain possible
remaining output data with CCCryptorFinal(). The CCCryptor is
disposed of via CCCryptorRelease(), or it can be reused (with
the same key data as provided to CCCryptorCreate()) by calling
CCCryptorReset().
CCCryptors can be dynamically allocated by this module, or
their memory can be allocated by the caller. See discussion for
CCCryptorCreate() and CCCryptorCreateFromData() for information
on CCCryptor allocation.
One option for block ciphers is padding, as defined in PKCS7;
when padding is enabled, the total amount of data encrypted
does not have to be an even multiple of the block size, and
the actual length of plaintext is calculated during decryption.
Another option for block ciphers is Cipher Block Chaining, known
as CBC mode. When using CBC mode, an Initialization Vector (IV)
is provided along with the key when starting an encrypt
or decrypt operation. If CBC mode is selected and no IV is
provided, an IV of all zeroes will be used.
CCCryptor also implements block bufferring, so that individual
calls to CCCryptorUpdate() do not have to provide data whose
length is aligned to the block size. (If padding is disabled,
encrypting with block ciphers does require that the *total*
length of data input to CCCryptorUpdate() call(s) be aligned
to the block size.)
A given CCCryptor can only be used by one thread at a time;
multiple threads can use safely different CCCryptors at the
same time.
*/
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