Use xoshiro256** to generate pseudo-random numbers.

[tinc] / src / crypto.h

diff --git a/src/crypto.h b/src/crypto.h
index 4c7d23b..9fc4156 100644 (file)
--- a/src/crypto.h
+++ b/src/crypto.h
@@ -24,6 +24,21 @@
 
 extern void crypto_init(void);
 extern void crypto_exit(void);
+extern uint64_t xoshiro(void);
+extern void prng_init(void);
+extern void prng_randomize(void *buf, size_t buflen);
 extern void randomize(void *buf, size_t buflen);
 
+static inline uint32_t prng(uint32_t limit) {
+       uint64_t bins = UINT64_MAX / limit;
+       uint64_t reject_after = bins * limit;
+       uint64_t value;
+
+       do {
+               value = xoshiro();
+       } while(value >= reject_after);
+
+       return value / bins;
+}
+
 #endif