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authorbcook <>2015-01-06 21:08:11 +0000
committerbcook <>2015-01-06 21:08:11 +0000
commit7ab5dcfb9695ddd10bc3141625c1a17be5b67bde (patch)
treeaf19259100728f885a25228ac4fa4e371670ec6b /src/lib
parenta6e31cd9243757b5df0b259fe6a94f654b53fcc4 (diff)
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add initial HP-UX getentropy/arc4random support.
patch from Kinichiro Inoguchi, tested on HP-UX 11.31 ok deraadt@
Diffstat (limited to 'src/lib')
-rw-r--r--src/lib/libcrypto/arc4random/arc4random_hpux.h79
-rw-r--r--src/lib/libcrypto/arc4random/getentropy_hpux.c417
-rw-r--r--src/lib/libcrypto/crypto/arc4random_hpux.h79
-rw-r--r--src/lib/libcrypto/crypto/getentropy_hpux.c417
4 files changed, 992 insertions, 0 deletions
diff --git a/src/lib/libcrypto/arc4random/arc4random_hpux.h b/src/lib/libcrypto/arc4random/arc4random_hpux.h
new file mode 100644
index 0000000000..b6841f583c
--- /dev/null
+++ b/src/lib/libcrypto/arc4random/arc4random_hpux.h
@@ -0,0 +1,79 @@
1/* $OpenBSD: arc4random_hpux.h,v 1.1 2015/01/06 21:08:11 bcook Exp $ */
2
3/*
4 * Copyright (c) 1996, David Mazieres <dm@uun.org>
5 * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
6 * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose with or without fee is hereby granted, provided that the above
10 * copyright notice and this permission notice appear in all copies.
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 */
20
21/*
22 * Stub functions for portability.
23 */
24
25#include <sys/mman.h>
26
27#include <pthread.h>
28#include <signal.h>
29
30static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
31#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
32#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
33
34#define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f))
35
36static inline void
37_getentropy_fail(void)
38{
39 raise(SIGKILL);
40}
41
42static volatile sig_atomic_t _rs_forked;
43
44static inline void
45_rs_forkhandler(void)
46{
47 _rs_forked = 1;
48}
49
50static inline void
51_rs_forkdetect(void)
52{
53 static pid_t _rs_pid = 0;
54 pid_t pid = getpid();
55
56 if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) {
57 _rs_pid = pid;
58 _rs_forked = 0;
59 if (rs)
60 memset(rs, 0, sizeof(*rs));
61 }
62}
63
64static inline int
65_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
66{
67 if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
68 MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
69 return (-1);
70
71 if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
72 MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
73 munmap(*rsp, sizeof(**rsp));
74 return (-1);
75 }
76
77 _ARC4_ATFORK(_rs_forkhandler);
78 return (0);
79}
diff --git a/src/lib/libcrypto/arc4random/getentropy_hpux.c b/src/lib/libcrypto/arc4random/getentropy_hpux.c
new file mode 100644
index 0000000000..46ab8f54d8
--- /dev/null
+++ b/src/lib/libcrypto/arc4random/getentropy_hpux.c
@@ -0,0 +1,417 @@
1/* $OpenBSD: getentropy_hpux.c,v 1.1 2015/01/06 21:08:11 bcook Exp $ */
2
3/*
4 * Copyright (c) 2014 Theo de Raadt <deraadt@openbsd.org>
5 * Copyright (c) 2014 Bob Beck <beck@obtuse.com>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 *
19 * Emulation of getentropy(2) as documented at:
20 * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2
21 */
22
23#include <sys/types.h>
24#include <sys/param.h>
25#include <sys/ioctl.h>
26#include <sys/resource.h>
27#include <sys/syscall.h>
28#include <sys/statvfs.h>
29#include <sys/socket.h>
30#include <sys/mount.h>
31#include <sys/mman.h>
32#include <sys/stat.h>
33#include <sys/time.h>
34#include <stdlib.h>
35#include <stdint.h>
36#include <stdio.h>
37#include <termios.h>
38#include <fcntl.h>
39#include <signal.h>
40#include <string.h>
41#include <errno.h>
42#include <unistd.h>
43#include <time.h>
44#include <openssl/sha.h>
45
46#include <sys/vfs.h>
47
48#include <sys/pstat.h>
49
50#define REPEAT 5
51#define min(a, b) (((a) < (b)) ? (a) : (b))
52
53#define HX(a, b) \
54 do { \
55 if ((a)) \
56 HD(errno); \
57 else \
58 HD(b); \
59 } while (0)
60
61#define HR(x, l) (SHA512_Update(&ctx, (char *)(x), (l)))
62#define HD(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (x)))
63#define HF(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (void*)))
64
65int getentropy(void *buf, size_t len);
66
67static int gotdata(char *buf, size_t len);
68static int getentropy_urandom(void *buf, size_t len, const char *path,
69 int devfscheck);
70static int getentropy_fallback(void *buf, size_t len);
71
72int
73getentropy(void *buf, size_t len)
74{
75 int ret = -1;
76
77 if (len > 256) {
78 errno = EIO;
79 return -1;
80 }
81
82 /*
83 * Try to get entropy with /dev/urandom
84 */
85 ret = getentropy_urandom(buf, len, "/dev/urandom", 0);
86 if (ret != -1)
87 return (ret);
88
89 /*
90 * Entropy collection via /dev/urandom has failed.
91 *
92 * No other API exists for collecting entropy, and we have
93 * no failsafe way to get it on hpux that is not sensitive
94 * to resource exhaustion.
95 *
96 * We have very few options:
97 * - Even syslog_r is unsafe to call at this low level, so
98 * there is no way to alert the user or program.
99 * - Cannot call abort() because some systems have unsafe
100 * corefiles.
101 * - Could raise(SIGKILL) resulting in silent program termination.
102 * - Return EIO, to hint that arc4random's stir function
103 * should raise(SIGKILL)
104 * - Do the best under the circumstances....
105 *
106 * This code path exists to bring light to the issue that hpux
107 * does not provide a failsafe API for entropy collection.
108 *
109 * We hope this demonstrates that hpux should consider
110 * providing a new failsafe API which works in a chroot or
111 * when file descriptors are exhausted.
112 */
113#undef FAIL_INSTEAD_OF_TRYING_FALLBACK
114#ifdef FAIL_INSTEAD_OF_TRYING_FALLBACK
115 raise(SIGKILL);
116#endif
117 ret = getentropy_fallback(buf, len);
118 if (ret != -1)
119 return (ret);
120
121 errno = EIO;
122 return (ret);
123}
124
125/*
126 * Basic sanity checking; wish we could do better.
127 */
128static int
129gotdata(char *buf, size_t len)
130{
131 char any_set = 0;
132 size_t i;
133
134 for (i = 0; i < len; ++i)
135 any_set |= buf[i];
136 if (any_set == 0)
137 return -1;
138 return 0;
139}
140
141static int
142getentropy_urandom(void *buf, size_t len, const char *path, int devfscheck)
143{
144 struct stat st;
145 size_t i;
146 int fd, flags;
147 int save_errno = errno;
148
149start:
150
151 flags = O_RDONLY;
152#ifdef O_NOFOLLOW
153 flags |= O_NOFOLLOW;
154#endif
155#ifdef O_CLOEXEC
156 flags |= O_CLOEXEC;
157#endif
158 fd = open(path, flags, 0);
159 if (fd == -1) {
160 if (errno == EINTR)
161 goto start;
162 goto nodevrandom;
163 }
164#ifndef O_CLOEXEC
165 fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
166#endif
167
168 /* Lightly verify that the device node looks sane */
169 if (fstat(fd, &st) == -1 || !S_ISCHR(st.st_mode)) {
170 close(fd);
171 goto nodevrandom;
172 }
173 for (i = 0; i < len; ) {
174 size_t wanted = len - i;
175 ssize_t ret = read(fd, (char *)buf + i, wanted);
176
177 if (ret == -1) {
178 if (errno == EAGAIN || errno == EINTR)
179 continue;
180 close(fd);
181 goto nodevrandom;
182 }
183 i += ret;
184 }
185 close(fd);
186 if (gotdata(buf, len) == 0) {
187 errno = save_errno;
188 return 0; /* satisfied */
189 }
190nodevrandom:
191 errno = EIO;
192 return -1;
193}
194
195static const int cl[] = {
196 CLOCK_REALTIME,
197#ifdef CLOCK_MONOTONIC
198 CLOCK_MONOTONIC,
199#endif
200#ifdef CLOCK_MONOTONIC_RAW
201 CLOCK_MONOTONIC_RAW,
202#endif
203#ifdef CLOCK_TAI
204 CLOCK_TAI,
205#endif
206#ifdef CLOCK_VIRTUAL
207 CLOCK_VIRTUAL,
208#endif
209#ifdef CLOCK_UPTIME
210 CLOCK_UPTIME,
211#endif
212#ifdef CLOCK_PROCESS_CPUTIME_ID
213 CLOCK_PROCESS_CPUTIME_ID,
214#endif
215#ifdef CLOCK_THREAD_CPUTIME_ID
216 CLOCK_THREAD_CPUTIME_ID,
217#endif
218};
219
220static int
221getentropy_fallback(void *buf, size_t len)
222{
223 uint8_t results[SHA512_DIGEST_LENGTH];
224 int save_errno = errno, e, pgs = sysconf(_SC_PAGESIZE), faster = 0, repeat;
225 static int cnt;
226 struct timespec ts;
227 struct timeval tv;
228 struct pst_vm_status pvs;
229 struct pst_dynamic pdy;
230 struct rusage ru;
231 sigset_t sigset;
232 struct stat st;
233 SHA512_CTX ctx;
234 static pid_t lastpid;
235 pid_t pid;
236 size_t i, ii, m;
237 char *p;
238
239 pid = getpid();
240 if (lastpid == pid) {
241 faster = 1;
242 repeat = 2;
243 } else {
244 faster = 0;
245 lastpid = pid;
246 repeat = REPEAT;
247 }
248 for (i = 0; i < len; ) {
249 int j;
250 SHA512_Init(&ctx);
251 for (j = 0; j < repeat; j++) {
252 HX((e = gettimeofday(&tv, NULL)) == -1, tv);
253 if (e != -1) {
254 cnt += (int)tv.tv_sec;
255 cnt += (int)tv.tv_usec;
256 }
257
258 HX(pstat_getprocvm(&pvs, sizeof(pvs), 0, 0) != 1, pvs.pst_space);
259
260 for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]); ii++)
261 HX(clock_gettime(cl[ii], &ts) == -1, ts);
262
263 HX((pid = getpid()) == -1, pid);
264 HX((pid = getsid(pid)) == -1, pid);
265 HX((pid = getppid()) == -1, pid);
266 HX((pid = getpgid(0)) == -1, pid);
267 HX((e = getpriority(0, 0)) == -1, e);
268
269 if(pstat_getdynamic(&pdy, sizeof(pdy), 1, 0) != 1) {
270 HD(errno);
271 } else {
272 HD(pdy.psd_avg_1_min);
273 HD(pdy.psd_avg_5_min);
274 HD(pdy.psd_avg_15_min);
275 }
276
277 if (!faster) {
278 ts.tv_sec = 0;
279 ts.tv_nsec = 1;
280 (void) nanosleep(&ts, NULL);
281 }
282
283 HX(sigpending(&sigset) == -1, sigset);
284 HX(sigprocmask(SIG_BLOCK, NULL, &sigset) == -1,
285 sigset);
286
287 HF(getentropy); /* an addr in this library */
288 HF(printf); /* an addr in libc */
289 p = (char *)&p;
290 HD(p); /* an addr on stack */
291 p = (char *)&errno;
292 HD(p); /* the addr of errno */
293
294 if (i == 0) {
295 struct sockaddr_storage ss;
296 struct statvfs stvfs;
297 struct termios tios;
298 socklen_t ssl;
299 off_t off;
300
301 /*
302 * Prime-sized mappings encourage fragmentation;
303 * thus exposing some address entropy.
304 */
305 struct mm {
306 size_t npg;
307 void *p;
308 } mm[] = {
309 { 17, MAP_FAILED }, { 3, MAP_FAILED },
310 { 11, MAP_FAILED }, { 2, MAP_FAILED },
311 { 5, MAP_FAILED }, { 3, MAP_FAILED },
312 { 7, MAP_FAILED }, { 1, MAP_FAILED },
313 { 57, MAP_FAILED }, { 3, MAP_FAILED },
314 { 131, MAP_FAILED }, { 1, MAP_FAILED },
315 };
316
317 for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
318 HX(mm[m].p = mmap(NULL,
319 mm[m].npg * pgs,
320 PROT_READ|PROT_WRITE,
321 MAP_PRIVATE|MAP_ANON, -1,
322 (off_t)0), mm[m].p);
323 if (mm[m].p != MAP_FAILED) {
324 size_t mo;
325
326 /* Touch some memory... */
327 p = mm[m].p;
328 mo = cnt %
329 (mm[m].npg * pgs - 1);
330 p[mo] = 1;
331 cnt += (int)((long)(mm[m].p)
332 / pgs);
333 }
334
335 /* Check cnts and times... */
336 for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]);
337 ii++) {
338 HX((e = clock_gettime(cl[ii],
339 &ts)) == -1, ts);
340 if (e != -1)
341 cnt += (int)ts.tv_nsec;
342 }
343
344 HX((e = getrusage(RUSAGE_SELF,
345 &ru)) == -1, ru);
346 if (e != -1) {
347 cnt += (int)ru.ru_utime.tv_sec;
348 cnt += (int)ru.ru_utime.tv_usec;
349 }
350 }
351
352 for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
353 if (mm[m].p != MAP_FAILED)
354 munmap(mm[m].p, mm[m].npg * pgs);
355 mm[m].p = MAP_FAILED;
356 }
357
358 HX(stat(".", &st) == -1, st);
359 HX(statvfs(".", &stvfs) == -1, stvfs);
360
361 HX(stat("/", &st) == -1, st);
362 HX(statvfs("/", &stvfs) == -1, stvfs);
363
364 HX((e = fstat(0, &st)) == -1, st);
365 if (e == -1) {
366 if (S_ISREG(st.st_mode) ||
367 S_ISFIFO(st.st_mode) ||
368 S_ISSOCK(st.st_mode)) {
369 HX(fstatvfs(0, &stvfs) == -1,
370 stvfs);
371 HX((off = lseek(0, (off_t)0,
372 SEEK_CUR)) < 0, off);
373 }
374 if (S_ISCHR(st.st_mode)) {
375 HX(tcgetattr(0, &tios) == -1,
376 tios);
377 } else if (S_ISSOCK(st.st_mode)) {
378 memset(&ss, 0, sizeof ss);
379 ssl = sizeof(ss);
380 HX(getpeername(0,
381 (void *)&ss, &ssl) == -1,
382 ss);
383 }
384 }
385
386 HX((e = getrusage(RUSAGE_CHILDREN,
387 &ru)) == -1, ru);
388 if (e != -1) {
389 cnt += (int)ru.ru_utime.tv_sec;
390 cnt += (int)ru.ru_utime.tv_usec;
391 }
392 } else {
393 /* Subsequent hashes absorb previous result */
394 HD(results);
395 }
396
397 HX((e = gettimeofday(&tv, NULL)) == -1, tv);
398 if (e != -1) {
399 cnt += (int)tv.tv_sec;
400 cnt += (int)tv.tv_usec;
401 }
402
403 HD(cnt);
404 }
405 SHA512_Final(results, &ctx);
406 memcpy((char *)buf + i, results, min(sizeof(results), len - i));
407 i += min(sizeof(results), len - i);
408 }
409 explicit_bzero(&ctx, sizeof ctx);
410 explicit_bzero(results, sizeof results);
411 if (gotdata(buf, len) == 0) {
412 errno = save_errno;
413 return 0; /* satisfied */
414 }
415 errno = EIO;
416 return -1;
417}
diff --git a/src/lib/libcrypto/crypto/arc4random_hpux.h b/src/lib/libcrypto/crypto/arc4random_hpux.h
new file mode 100644
index 0000000000..b6841f583c
--- /dev/null
+++ b/src/lib/libcrypto/crypto/arc4random_hpux.h
@@ -0,0 +1,79 @@
1/* $OpenBSD: arc4random_hpux.h,v 1.1 2015/01/06 21:08:11 bcook Exp $ */
2
3/*
4 * Copyright (c) 1996, David Mazieres <dm@uun.org>
5 * Copyright (c) 2008, Damien Miller <djm@openbsd.org>
6 * Copyright (c) 2013, Markus Friedl <markus@openbsd.org>
7 *
8 * Permission to use, copy, modify, and distribute this software for any
9 * purpose with or without fee is hereby granted, provided that the above
10 * copyright notice and this permission notice appear in all copies.
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 */
20
21/*
22 * Stub functions for portability.
23 */
24
25#include <sys/mman.h>
26
27#include <pthread.h>
28#include <signal.h>
29
30static pthread_mutex_t arc4random_mtx = PTHREAD_MUTEX_INITIALIZER;
31#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
32#define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
33
34#define _ARC4_ATFORK(f) pthread_atfork(NULL, NULL, (f))
35
36static inline void
37_getentropy_fail(void)
38{
39 raise(SIGKILL);
40}
41
42static volatile sig_atomic_t _rs_forked;
43
44static inline void
45_rs_forkhandler(void)
46{
47 _rs_forked = 1;
48}
49
50static inline void
51_rs_forkdetect(void)
52{
53 static pid_t _rs_pid = 0;
54 pid_t pid = getpid();
55
56 if (_rs_pid == 0 || _rs_pid != pid || _rs_forked) {
57 _rs_pid = pid;
58 _rs_forked = 0;
59 if (rs)
60 memset(rs, 0, sizeof(*rs));
61 }
62}
63
64static inline int
65_rs_allocate(struct _rs **rsp, struct _rsx **rsxp)
66{
67 if ((*rsp = mmap(NULL, sizeof(**rsp), PROT_READ|PROT_WRITE,
68 MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED)
69 return (-1);
70
71 if ((*rsxp = mmap(NULL, sizeof(**rsxp), PROT_READ|PROT_WRITE,
72 MAP_ANON|MAP_PRIVATE, -1, 0)) == MAP_FAILED) {
73 munmap(*rsp, sizeof(**rsp));
74 return (-1);
75 }
76
77 _ARC4_ATFORK(_rs_forkhandler);
78 return (0);
79}
diff --git a/src/lib/libcrypto/crypto/getentropy_hpux.c b/src/lib/libcrypto/crypto/getentropy_hpux.c
new file mode 100644
index 0000000000..46ab8f54d8
--- /dev/null
+++ b/src/lib/libcrypto/crypto/getentropy_hpux.c
@@ -0,0 +1,417 @@
1/* $OpenBSD: getentropy_hpux.c,v 1.1 2015/01/06 21:08:11 bcook Exp $ */
2
3/*
4 * Copyright (c) 2014 Theo de Raadt <deraadt@openbsd.org>
5 * Copyright (c) 2014 Bob Beck <beck@obtuse.com>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 *
19 * Emulation of getentropy(2) as documented at:
20 * http://www.openbsd.org/cgi-bin/man.cgi/OpenBSD-current/man2/getentropy.2
21 */
22
23#include <sys/types.h>
24#include <sys/param.h>
25#include <sys/ioctl.h>
26#include <sys/resource.h>
27#include <sys/syscall.h>
28#include <sys/statvfs.h>
29#include <sys/socket.h>
30#include <sys/mount.h>
31#include <sys/mman.h>
32#include <sys/stat.h>
33#include <sys/time.h>
34#include <stdlib.h>
35#include <stdint.h>
36#include <stdio.h>
37#include <termios.h>
38#include <fcntl.h>
39#include <signal.h>
40#include <string.h>
41#include <errno.h>
42#include <unistd.h>
43#include <time.h>
44#include <openssl/sha.h>
45
46#include <sys/vfs.h>
47
48#include <sys/pstat.h>
49
50#define REPEAT 5
51#define min(a, b) (((a) < (b)) ? (a) : (b))
52
53#define HX(a, b) \
54 do { \
55 if ((a)) \
56 HD(errno); \
57 else \
58 HD(b); \
59 } while (0)
60
61#define HR(x, l) (SHA512_Update(&ctx, (char *)(x), (l)))
62#define HD(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (x)))
63#define HF(x) (SHA512_Update(&ctx, (char *)&(x), sizeof (void*)))
64
65int getentropy(void *buf, size_t len);
66
67static int gotdata(char *buf, size_t len);
68static int getentropy_urandom(void *buf, size_t len, const char *path,
69 int devfscheck);
70static int getentropy_fallback(void *buf, size_t len);
71
72int
73getentropy(void *buf, size_t len)
74{
75 int ret = -1;
76
77 if (len > 256) {
78 errno = EIO;
79 return -1;
80 }
81
82 /*
83 * Try to get entropy with /dev/urandom
84 */
85 ret = getentropy_urandom(buf, len, "/dev/urandom", 0);
86 if (ret != -1)
87 return (ret);
88
89 /*
90 * Entropy collection via /dev/urandom has failed.
91 *
92 * No other API exists for collecting entropy, and we have
93 * no failsafe way to get it on hpux that is not sensitive
94 * to resource exhaustion.
95 *
96 * We have very few options:
97 * - Even syslog_r is unsafe to call at this low level, so
98 * there is no way to alert the user or program.
99 * - Cannot call abort() because some systems have unsafe
100 * corefiles.
101 * - Could raise(SIGKILL) resulting in silent program termination.
102 * - Return EIO, to hint that arc4random's stir function
103 * should raise(SIGKILL)
104 * - Do the best under the circumstances....
105 *
106 * This code path exists to bring light to the issue that hpux
107 * does not provide a failsafe API for entropy collection.
108 *
109 * We hope this demonstrates that hpux should consider
110 * providing a new failsafe API which works in a chroot or
111 * when file descriptors are exhausted.
112 */
113#undef FAIL_INSTEAD_OF_TRYING_FALLBACK
114#ifdef FAIL_INSTEAD_OF_TRYING_FALLBACK
115 raise(SIGKILL);
116#endif
117 ret = getentropy_fallback(buf, len);
118 if (ret != -1)
119 return (ret);
120
121 errno = EIO;
122 return (ret);
123}
124
125/*
126 * Basic sanity checking; wish we could do better.
127 */
128static int
129gotdata(char *buf, size_t len)
130{
131 char any_set = 0;
132 size_t i;
133
134 for (i = 0; i < len; ++i)
135 any_set |= buf[i];
136 if (any_set == 0)
137 return -1;
138 return 0;
139}
140
141static int
142getentropy_urandom(void *buf, size_t len, const char *path, int devfscheck)
143{
144 struct stat st;
145 size_t i;
146 int fd, flags;
147 int save_errno = errno;
148
149start:
150
151 flags = O_RDONLY;
152#ifdef O_NOFOLLOW
153 flags |= O_NOFOLLOW;
154#endif
155#ifdef O_CLOEXEC
156 flags |= O_CLOEXEC;
157#endif
158 fd = open(path, flags, 0);
159 if (fd == -1) {
160 if (errno == EINTR)
161 goto start;
162 goto nodevrandom;
163 }
164#ifndef O_CLOEXEC
165 fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
166#endif
167
168 /* Lightly verify that the device node looks sane */
169 if (fstat(fd, &st) == -1 || !S_ISCHR(st.st_mode)) {
170 close(fd);
171 goto nodevrandom;
172 }
173 for (i = 0; i < len; ) {
174 size_t wanted = len - i;
175 ssize_t ret = read(fd, (char *)buf + i, wanted);
176
177 if (ret == -1) {
178 if (errno == EAGAIN || errno == EINTR)
179 continue;
180 close(fd);
181 goto nodevrandom;
182 }
183 i += ret;
184 }
185 close(fd);
186 if (gotdata(buf, len) == 0) {
187 errno = save_errno;
188 return 0; /* satisfied */
189 }
190nodevrandom:
191 errno = EIO;
192 return -1;
193}
194
195static const int cl[] = {
196 CLOCK_REALTIME,
197#ifdef CLOCK_MONOTONIC
198 CLOCK_MONOTONIC,
199#endif
200#ifdef CLOCK_MONOTONIC_RAW
201 CLOCK_MONOTONIC_RAW,
202#endif
203#ifdef CLOCK_TAI
204 CLOCK_TAI,
205#endif
206#ifdef CLOCK_VIRTUAL
207 CLOCK_VIRTUAL,
208#endif
209#ifdef CLOCK_UPTIME
210 CLOCK_UPTIME,
211#endif
212#ifdef CLOCK_PROCESS_CPUTIME_ID
213 CLOCK_PROCESS_CPUTIME_ID,
214#endif
215#ifdef CLOCK_THREAD_CPUTIME_ID
216 CLOCK_THREAD_CPUTIME_ID,
217#endif
218};
219
220static int
221getentropy_fallback(void *buf, size_t len)
222{
223 uint8_t results[SHA512_DIGEST_LENGTH];
224 int save_errno = errno, e, pgs = sysconf(_SC_PAGESIZE), faster = 0, repeat;
225 static int cnt;
226 struct timespec ts;
227 struct timeval tv;
228 struct pst_vm_status pvs;
229 struct pst_dynamic pdy;
230 struct rusage ru;
231 sigset_t sigset;
232 struct stat st;
233 SHA512_CTX ctx;
234 static pid_t lastpid;
235 pid_t pid;
236 size_t i, ii, m;
237 char *p;
238
239 pid = getpid();
240 if (lastpid == pid) {
241 faster = 1;
242 repeat = 2;
243 } else {
244 faster = 0;
245 lastpid = pid;
246 repeat = REPEAT;
247 }
248 for (i = 0; i < len; ) {
249 int j;
250 SHA512_Init(&ctx);
251 for (j = 0; j < repeat; j++) {
252 HX((e = gettimeofday(&tv, NULL)) == -1, tv);
253 if (e != -1) {
254 cnt += (int)tv.tv_sec;
255 cnt += (int)tv.tv_usec;
256 }
257
258 HX(pstat_getprocvm(&pvs, sizeof(pvs), 0, 0) != 1, pvs.pst_space);
259
260 for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]); ii++)
261 HX(clock_gettime(cl[ii], &ts) == -1, ts);
262
263 HX((pid = getpid()) == -1, pid);
264 HX((pid = getsid(pid)) == -1, pid);
265 HX((pid = getppid()) == -1, pid);
266 HX((pid = getpgid(0)) == -1, pid);
267 HX((e = getpriority(0, 0)) == -1, e);
268
269 if(pstat_getdynamic(&pdy, sizeof(pdy), 1, 0) != 1) {
270 HD(errno);
271 } else {
272 HD(pdy.psd_avg_1_min);
273 HD(pdy.psd_avg_5_min);
274 HD(pdy.psd_avg_15_min);
275 }
276
277 if (!faster) {
278 ts.tv_sec = 0;
279 ts.tv_nsec = 1;
280 (void) nanosleep(&ts, NULL);
281 }
282
283 HX(sigpending(&sigset) == -1, sigset);
284 HX(sigprocmask(SIG_BLOCK, NULL, &sigset) == -1,
285 sigset);
286
287 HF(getentropy); /* an addr in this library */
288 HF(printf); /* an addr in libc */
289 p = (char *)&p;
290 HD(p); /* an addr on stack */
291 p = (char *)&errno;
292 HD(p); /* the addr of errno */
293
294 if (i == 0) {
295 struct sockaddr_storage ss;
296 struct statvfs stvfs;
297 struct termios tios;
298 socklen_t ssl;
299 off_t off;
300
301 /*
302 * Prime-sized mappings encourage fragmentation;
303 * thus exposing some address entropy.
304 */
305 struct mm {
306 size_t npg;
307 void *p;
308 } mm[] = {
309 { 17, MAP_FAILED }, { 3, MAP_FAILED },
310 { 11, MAP_FAILED }, { 2, MAP_FAILED },
311 { 5, MAP_FAILED }, { 3, MAP_FAILED },
312 { 7, MAP_FAILED }, { 1, MAP_FAILED },
313 { 57, MAP_FAILED }, { 3, MAP_FAILED },
314 { 131, MAP_FAILED }, { 1, MAP_FAILED },
315 };
316
317 for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
318 HX(mm[m].p = mmap(NULL,
319 mm[m].npg * pgs,
320 PROT_READ|PROT_WRITE,
321 MAP_PRIVATE|MAP_ANON, -1,
322 (off_t)0), mm[m].p);
323 if (mm[m].p != MAP_FAILED) {
324 size_t mo;
325
326 /* Touch some memory... */
327 p = mm[m].p;
328 mo = cnt %
329 (mm[m].npg * pgs - 1);
330 p[mo] = 1;
331 cnt += (int)((long)(mm[m].p)
332 / pgs);
333 }
334
335 /* Check cnts and times... */
336 for (ii = 0; ii < sizeof(cl)/sizeof(cl[0]);
337 ii++) {
338 HX((e = clock_gettime(cl[ii],
339 &ts)) == -1, ts);
340 if (e != -1)
341 cnt += (int)ts.tv_nsec;
342 }
343
344 HX((e = getrusage(RUSAGE_SELF,
345 &ru)) == -1, ru);
346 if (e != -1) {
347 cnt += (int)ru.ru_utime.tv_sec;
348 cnt += (int)ru.ru_utime.tv_usec;
349 }
350 }
351
352 for (m = 0; m < sizeof mm/sizeof(mm[0]); m++) {
353 if (mm[m].p != MAP_FAILED)
354 munmap(mm[m].p, mm[m].npg * pgs);
355 mm[m].p = MAP_FAILED;
356 }
357
358 HX(stat(".", &st) == -1, st);
359 HX(statvfs(".", &stvfs) == -1, stvfs);
360
361 HX(stat("/", &st) == -1, st);
362 HX(statvfs("/", &stvfs) == -1, stvfs);
363
364 HX((e = fstat(0, &st)) == -1, st);
365 if (e == -1) {
366 if (S_ISREG(st.st_mode) ||
367 S_ISFIFO(st.st_mode) ||
368 S_ISSOCK(st.st_mode)) {
369 HX(fstatvfs(0, &stvfs) == -1,
370 stvfs);
371 HX((off = lseek(0, (off_t)0,
372 SEEK_CUR)) < 0, off);
373 }
374 if (S_ISCHR(st.st_mode)) {
375 HX(tcgetattr(0, &tios) == -1,
376 tios);
377 } else if (S_ISSOCK(st.st_mode)) {
378 memset(&ss, 0, sizeof ss);
379 ssl = sizeof(ss);
380 HX(getpeername(0,
381 (void *)&ss, &ssl) == -1,
382 ss);
383 }
384 }
385
386 HX((e = getrusage(RUSAGE_CHILDREN,
387 &ru)) == -1, ru);
388 if (e != -1) {
389 cnt += (int)ru.ru_utime.tv_sec;
390 cnt += (int)ru.ru_utime.tv_usec;
391 }
392 } else {
393 /* Subsequent hashes absorb previous result */
394 HD(results);
395 }
396
397 HX((e = gettimeofday(&tv, NULL)) == -1, tv);
398 if (e != -1) {
399 cnt += (int)tv.tv_sec;
400 cnt += (int)tv.tv_usec;
401 }
402
403 HD(cnt);
404 }
405 SHA512_Final(results, &ctx);
406 memcpy((char *)buf + i, results, min(sizeof(results), len - i));
407 i += min(sizeof(results), len - i);
408 }
409 explicit_bzero(&ctx, sizeof ctx);
410 explicit_bzero(results, sizeof results);
411 if (gotdata(buf, len) == 0) {
412 errno = save_errno;
413 return 0; /* satisfied */
414 }
415 errno = EIO;
416 return -1;
417}
generated by cgit v1.2.3-55-g6feb (git 2.39.1) at 2025-03-23 00:52:51 +0000