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Signature Algorithms

OPENSSL_ALGO_SHA1 (integer)
Used as default algorithm by openssl_sign() and openssl_verify().
OPENSSL_ALGO_MD5 (integer)
OPENSSL_ALGO_MD4 (integer)
OPENSSL_ALGO_MD2 (integer)

Note: These constants were added in 5.0.0.


预定义常量
PHP 手册