1 /* 2 * Copyright (c) 2017 Carlo Marcelo Arenas Beln <carenas (at) gmail.com> 3 * 4 * This program is free software: you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation, either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 /* 18 * Very basic test for the RND* ioctls. 19 * 20 * Reads the entropy available from both /proc and the ioctl and compares 21 * they are similar enough (within a configured fuzz factor) 22 * 23 */ 24 25 #include <asm/types.h> 26 #include <linux/random.h> 27 #include <stdlib.h> 28 #include "tst_test.h" 29 30 static char *s_fuzz; 31 static int fuzz = 2; 32 static struct tst_option options[] = { 33 {"f:", &s_fuzz, "-f c Fuzz factor for valid match (default 2)"}, 34 {NULL, NULL, NULL} 35 }; 36 static int fd; 37 38 static void verify_ioctl(void) 39 { 40 int cnt, pcnt; 41 42 SAFE_IOCTL(fd, RNDGETENTCNT, &cnt); 43 SAFE_FILE_SCANF("/proc/sys/kernel/random/entropy_avail", "%d", &pcnt); 44 tst_res(TINFO, "entropy value from ioctl: %d, proc: %d", cnt, pcnt); 45 46 if (abs(pcnt - cnt) <= fuzz) 47 tst_res(TPASS, "entropy value within expected parameters"); 48 else 49 tst_res(TFAIL, "incorrect entropy value from ioctl"); 50 } 51 52 static void setup(void) 53 { 54 fd = SAFE_OPEN("/dev/urandom", O_RDONLY); 55 if (s_fuzz) 56 fuzz = SAFE_STRTOL(s_fuzz, 0, 4096); 57 } 58 59 static void cleanup(void) 60 { 61 if (fd > 0) 62 SAFE_CLOSE(fd); 63 } 64 65 static struct tst_test test = { 66 .setup = setup, 67 .cleanup = cleanup, 68 .options = options, 69 .test_all = verify_ioctl, 70 }; 71
