47  * Always use the getentropy implementation from bsd-getentropy.c, which
75 #define REKEY_BASE	(1024*1024) /* NB. should be a power of 2 */
102 		if (_rs_allocate(&rs, &rsx) == -1)  in _rs_init()
106 	chacha_keysetup(&rsx->rs_chacha, buf, KEYSZ * 8);  in _rs_init()
107 	chacha_ivsetup(&rsx->rs_chacha, buf + KEYSZ);  in _rs_init()
116 	if (getentropy(rnd, sizeof rnd) == -1)  in _rs_stir()
126 	rs->rs_have = 0;  in _rs_stir()
127 	memset(rsx->rs_buf, 0, sizeof(rsx->rs_buf));  in _rs_stir()
130 	chacha_encrypt_bytes(&rsx->rs_chacha, (uint8_t *)&rekey_fuzz,  in _rs_stir()
132 	rs->rs_count = REKEY_BASE + (rekey_fuzz % REKEY_BASE);  in _rs_stir()
139 	if (!rs || rs->rs_count <= len)  in _rs_stir_if_needed()
141 	if (rs->rs_count <= len)  in _rs_stir_if_needed()
142 		rs->rs_count = 0;  in _rs_stir_if_needed()
144 		rs->rs_count -= len;  in _rs_stir_if_needed()
151 	memset(rsx->rs_buf, 0, sizeof(rsx->rs_buf));  in _rs_rekey()
154 	chacha_encrypt_bytes(&rsx->rs_chacha, rsx->rs_buf,  in _rs_rekey()
155 	    rsx->rs_buf, sizeof(rsx->rs_buf));  in _rs_rekey()
162 			rsx->rs_buf[i] ^= dat[i];  in _rs_rekey()
165 	_rs_init(rsx->rs_buf, KEYSZ + IVSZ);  in _rs_rekey()
166 	memset(rsx->rs_buf, 0, KEYSZ + IVSZ);  in _rs_rekey()
167 	rs->rs_have = sizeof(rsx->rs_buf) - KEYSZ - IVSZ;  in _rs_rekey()
179 		if (rs->rs_have > 0) {  in _rs_random_buf()
180 			m = minimum(n, rs->rs_have);  in _rs_random_buf()
181 			keystream = rsx->rs_buf + sizeof(rsx->rs_buf)  in _rs_random_buf()
182 			    - rs->rs_have;  in _rs_random_buf()
186 			n -= m;  in _rs_random_buf()
187 			rs->rs_have -= m;  in _rs_random_buf()
189 		if (rs->rs_have == 0)  in _rs_random_buf()
200 	if (rs->rs_have < sizeof(*val))  in _rs_random_u32()
202 	keystream = rsx->rs_buf + sizeof(rsx->rs_buf) - rs->rs_have;  in _rs_random_u32()
205 	rs->rs_have -= sizeof(*val);  in _rs_random_u32()
221  * If we are providing arc4random, then we can provide a more efficient