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35 #include "util_random.h"
41 #include <openssl/err.h>
42 #include <openssl/rand.h>
46 bool randGenPseudoRandom(unsigned char *buffer, size_t len)
49 std::random_device rd; // slow; use to seed only!
50 std::mt19937 gen(rd()); // seed mersenne twister.
51 std::uniform_int_distribution<> dist(0,UCHAR_MAX);
52 for (size_t i=0; i<len; i++)
53 buffer[i] = dist(gen);
55 #elif defined(HAVE_OPENSSL)
57 bool existingErrors = false;
60 // See if there are any queued OpenSSL errors already.
61 existingErrors = ( 0 == ERR_peek_error() );
65 // Generate random byte string
66 osslReturn = RAND_pseudo_bytes(buffer, len);
68 // Discard the error message if there weren't any OpenSSL errors to begin with.
69 if (osslReturn == 1 && !existingErrors)
71 while (0 != ERR_get_error() );
76 #error no pseudo random generator available