Generate a string of highly randomized bytes (over the full 8-bit range).
|int||$length||Number of bytes needed |
- string Random bytes
- George Argyros firstname.lastname@example.org@m.eorge.nosp@m.@email@example.com@m.m
- 2012, George Argyros. All rights reserved. Modified BSD Original Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.Neither the name of the nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
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Our primary choice for a cryptographic strong randomness function is openssl_random_pseudo_bytes.
If mcrypt extension is available then we use it to gather entropy from the operating system's PRNG. This is better than reading /dev/urandom directly since it avoids reading larger blocks of data than needed.
No build-in crypto randomness function found. We collect any entropy available in the PHP core PRNGs along with some filesystem info and memory stats. To make this data cryptographically strong we add data either from /dev/urandom or if its unavailable, we gather entropy by measuring the time needed to compute a number of SHA-1 hashes.
Definition at line 72 of file ElggCrypto.php.