/* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include #include #include #include #include #include #include #include #include #include #include #include #include "secrng.h" #include "secerr.h" #include "prerror.h" #include "prthread.h" #include "prprf.h" #include "prenv.h" size_t RNG_FileUpdate(const char *fileName, size_t limit); /* * When copying data to the buffer we want the least signicant bytes * from the input since those bits are changing the fastest. The address * of least significant byte depends upon whether we are running on * a big-endian or little-endian machine. * * Does this mean the least signicant bytes are the most significant * to us? :-) */ static size_t CopyLowBits(void *dst, size_t dstlen, void *src, size_t srclen) { union endianness { PRInt32 i; char c[4]; } u; if (srclen <= dstlen) { memcpy(dst, src, srclen); return srclen; } u.i = 0x01020304; if (u.c[0] == 0x01) { /* big-endian case */ memcpy(dst, (char *)src + (srclen - dstlen), dstlen); } else { /* little-endian case */ memcpy(dst, src, dstlen); } return dstlen; } #ifdef SOLARIS #include static const PRUint32 entropy_buf_len = 4096; /* buffer up to 4 KB */ /* Buffer entropy data, and feed it to the RNG, entropy_buf_len bytes at a time. * Returns error if RNG_RandomUpdate fails. Also increments *total_fed * by the number of bytes successfully buffered. */ static SECStatus BufferEntropy(char *inbuf, PRUint32 inlen, char *entropy_buf, PRUint32 *entropy_buffered, PRUint32 *total_fed) { PRUint32 tocopy = 0; PRUint32 avail = 0; SECStatus rv = SECSuccess; while (inlen) { avail = entropy_buf_len - *entropy_buffered; if (!avail) { /* Buffer is full, time to feed it to the RNG. */ rv = RNG_RandomUpdate(entropy_buf, entropy_buf_len); if (SECSuccess != rv) { break; } *entropy_buffered = 0; avail = entropy_buf_len; } tocopy = PR_MIN(avail, inlen); memcpy(entropy_buf + *entropy_buffered, inbuf, tocopy); *entropy_buffered += tocopy; inlen -= tocopy; inbuf += tocopy; *total_fed += tocopy; } return rv; } /* Feed kernel statistics structures and ks_data field to the RNG. * Returns status as well as the number of bytes successfully fed to the RNG. */ static SECStatus RNG_kstat(PRUint32 *fed) { kstat_ctl_t *kc = NULL; kstat_t *ksp = NULL; PRUint32 entropy_buffered = 0; char *entropy_buf = NULL; SECStatus rv = SECSuccess; PORT_Assert(fed); if (!fed) { return SECFailure; } *fed = 0; kc = kstat_open(); PORT_Assert(kc); if (!kc) { return SECFailure; } entropy_buf = (char *)PORT_Alloc(entropy_buf_len); PORT_Assert(entropy_buf); if (entropy_buf) { for (ksp = kc->kc_chain; ksp != NULL; ksp = ksp->ks_next) { if (-1 == kstat_read(kc, ksp, NULL)) { /* missing data from a single kstat shouldn't be fatal */ continue; } rv = BufferEntropy((char *)ksp, sizeof(kstat_t), entropy_buf, &entropy_buffered, fed); if (SECSuccess != rv) { break; } if (ksp->ks_data && ksp->ks_data_size > 0 && ksp->ks_ndata > 0) { rv = BufferEntropy((char *)ksp->ks_data, ksp->ks_data_size, entropy_buf, &entropy_buffered, fed); if (SECSuccess != rv) { break; } } } if (SECSuccess == rv && entropy_buffered) { /* Buffer is not empty, time to feed it to the RNG */ rv = RNG_RandomUpdate(entropy_buf, entropy_buffered); } PORT_Free(entropy_buf); } else { rv = SECFailure; } if (kstat_close(kc)) { PORT_Assert(0); rv = SECFailure; } return rv; } #endif #if defined(SCO) || defined(UNIXWARE) || defined(BSDI) || defined(FREEBSD) || defined(NETBSD) || defined(DARWIN) || defined(OPENBSD) || defined(NTO) || defined(__riscos__) || defined(__GNU__) || defined(__FreeBSD_kernel__) || defined(__NetBSD_kernel__) #include static size_t GetHighResClock(void *buf, size_t maxbytes) { int ticks; struct tms buffer; ticks = times(&buffer); return CopyLowBits(buf, maxbytes, &ticks, sizeof(ticks)); } static void GiveSystemInfo(void) { long si; /* * Is this really necessary? Why not use rand48 or something? */ si = sysconf(_SC_CHILD_MAX); RNG_RandomUpdate(&si, sizeof(si)); si = sysconf(_SC_STREAM_MAX); RNG_RandomUpdate(&si, sizeof(si)); si = sysconf(_SC_OPEN_MAX); RNG_RandomUpdate(&si, sizeof(si)); } #endif #if defined(__sun) #if defined(__svr4) || defined(SVR4) #include static void GiveSystemInfo(void) { int rv; char buf[2000]; rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } static size_t GetHighResClock(void *buf, size_t maxbytes) { hrtime_t t; t = gethrtime(); if (t) { return CopyLowBits(buf, maxbytes, &t, sizeof(t)); } return 0; } #else /* SunOS (Sun, but not SVR4) */ extern long sysconf(int name); static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { long si; /* This is not very good */ si = sysconf(_SC_CHILD_MAX); RNG_RandomUpdate(&si, sizeof(si)); } #endif #endif /* Sun */ #if defined(__hpux) #include #if defined(__ia64) #include static size_t GetHighResClock(void *buf, size_t maxbytes) { PRUint64 t; t = _Asm_mov_from_ar(_AREG44); return CopyLowBits(buf, maxbytes, &t, sizeof(t)); } #else static size_t GetHighResClock(void *buf, size_t maxbytes) { extern int ret_cr16(); int cr16val; cr16val = ret_cr16(); return CopyLowBits(buf, maxbytes, &cr16val, sizeof(cr16val)); } #endif static void GiveSystemInfo(void) { long si; /* This is not very good */ si = sysconf(_AES_OS_VERSION); RNG_RandomUpdate(&si, sizeof(si)); si = sysconf(_SC_CPU_VERSION); RNG_RandomUpdate(&si, sizeof(si)); } #endif /* HPUX */ #if defined(_IBMR2) static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { /* XXX haven't found any yet! */ } #endif /* IBM R2 */ #if defined(LINUX) #include static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { #ifndef NO_SYSINFO struct sysinfo si; if (sysinfo(&si) == 0) { RNG_RandomUpdate(&si, sizeof(si)); } #endif } #endif /* LINUX */ #if defined(NCR) #include #include static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { int rv; char buf[2000]; rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } #endif /* NCR */ #if defined(sgi) #include #undef PRIVATE #include #include #include #include #include #include static void GiveSystemInfo(void) { int rv; char buf[4096]; rv = syssgi(SGI_SYSID, &buf[0]); if (rv > 0) { RNG_RandomUpdate(buf, MAXSYSIDSIZE); } #ifdef SGI_RDUBLK rv = syssgi(SGI_RDUBLK, getpid(), &buf[0], sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, sizeof(buf)); } #endif /* SGI_RDUBLK */ rv = syssgi(SGI_INVENT, SGI_INV_READ, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, sizeof(buf)); } rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } static size_t GetHighResClock(void *buf, size_t maxbuf) { unsigned phys_addr, raddr, cycleval; static volatile unsigned *iotimer_addr = NULL; static int tries = 0; static int cntr_size; int mfd; long s0[2]; struct timeval tv; #ifndef SGI_CYCLECNTR_SIZE #define SGI_CYCLECNTR_SIZE 165 /* Size user needs to use to read CC */ #endif if (iotimer_addr == NULL) { if (tries++ > 1) { /* Don't keep trying if it didn't work */ return 0; } /* ** For SGI machines we can use the cycle counter, if it has one, ** to generate some truly random numbers */ phys_addr = syssgi(SGI_QUERY_CYCLECNTR, &cycleval); if (phys_addr) { int pgsz = getpagesize(); int pgoffmask = pgsz - 1; raddr = phys_addr & ~pgoffmask; mfd = open("/dev/mmem", O_RDONLY); if (mfd < 0) { return 0; } iotimer_addr = (unsigned *) mmap(0, pgoffmask, PROT_READ, MAP_PRIVATE, mfd, (int)raddr); if (iotimer_addr == (void *)-1) { close(mfd); iotimer_addr = NULL; return 0; } iotimer_addr = (unsigned *)((__psint_t)iotimer_addr | (phys_addr & pgoffmask)); /* * The file 'mfd' is purposefully not closed. */ cntr_size = syssgi(SGI_CYCLECNTR_SIZE); if (cntr_size < 0) { struct utsname utsinfo; /* * We must be executing on a 6.0 or earlier system, since the * SGI_CYCLECNTR_SIZE call is not supported. * * The only pre-6.1 platforms with 64-bit counters are * IP19 and IP21 (Challenge, PowerChallenge, Onyx). */ uname(&utsinfo); if (!strncmp(utsinfo.machine, "IP19", 4) || !strncmp(utsinfo.machine, "IP21", 4)) cntr_size = 64; else cntr_size = 32; } cntr_size /= 8; /* Convert from bits to bytes */ } } s0[0] = *iotimer_addr; if (cntr_size > 4) s0[1] = *(iotimer_addr + 1); memcpy(buf, (char *)&s0[0], cntr_size); return CopyLowBits(buf, maxbuf, &s0, cntr_size); } #endif #if defined(sony) #include static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { int rv; char buf[2000]; rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } #endif /* sony */ #if defined(sinix) #include #include int gettimeofday(struct timeval *, struct timezone *); int gethostname(char *, int); static size_t GetHighResClock(void *buf, size_t maxbytes) { int ticks; struct tms buffer; ticks = times(&buffer); return CopyLowBits(buf, maxbytes, &ticks, sizeof(ticks)); } static void GiveSystemInfo(void) { int rv; char buf[2000]; rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } #endif /* sinix */ #if defined(nec_ews) #include static size_t GetHighResClock(void *buf, size_t maxbytes) { return 0; } static void GiveSystemInfo(void) { int rv; char buf[2000]; rv = sysinfo(SI_MACHINE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_RELEASE, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } rv = sysinfo(SI_HW_SERIAL, buf, sizeof(buf)); if (rv > 0) { RNG_RandomUpdate(buf, rv); } } #endif /* nec_ews */ size_t RNG_GetNoise(void *buf, size_t maxbytes) { struct timeval tv; int n = 0; int c; n = GetHighResClock(buf, maxbytes); maxbytes -= n; (void)gettimeofday(&tv, 0); c = CopyLowBits((char *)buf + n, maxbytes, &tv.tv_usec, sizeof(tv.tv_usec)); n += c; maxbytes -= c; c = CopyLowBits((char *)buf + n, maxbytes, &tv.tv_sec, sizeof(tv.tv_sec)); n += c; return n; } #ifdef DARWIN #include #if !TARGET_OS_IPHONE #include #endif #endif void RNG_SystemInfoForRNG(void) { char buf[BUFSIZ]; size_t bytes; const char *const *cp; char *randfile; #ifdef DARWIN #if TARGET_OS_IPHONE /* iOS does not expose a way to access environ. */ char **environ = NULL; #else char **environ = *_NSGetEnviron(); #endif #else extern char **environ; #endif static const char *const files[] = { "/etc/passwd", "/etc/utmp", "/tmp", "/var/tmp", "/usr/tmp", 0 }; GiveSystemInfo(); bytes = RNG_GetNoise(buf, sizeof(buf)); RNG_RandomUpdate(buf, bytes); /* * Pass the C environment and the addresses of the pointers to the * hash function. This makes the random number function depend on the * execution environment of the user and on the platform the program * is running on. */ if (environ != NULL) { cp = (const char *const *)environ; while (*cp) { RNG_RandomUpdate(*cp, strlen(*cp)); cp++; } RNG_RandomUpdate(environ, (char *)cp - (char *)environ); } /* Give in system information */ if (gethostname(buf, sizeof(buf)) == 0) { RNG_RandomUpdate(buf, strlen(buf)); } /* grab some data from system's PRNG before any other files. */ bytes = RNG_FileUpdate("/dev/urandom", SYSTEM_RNG_SEED_COUNT); if (!bytes) { PORT_SetError(SEC_ERROR_NEED_RANDOM); } /* If the user points us to a random file, pass it through the rng */ randfile = PR_GetEnvSecure("NSRANDFILE"); if ((randfile != NULL) && (randfile[0] != '\0')) { char *randCountString = PR_GetEnvSecure("NSRANDCOUNT"); int randCount = randCountString ? atoi(randCountString) : 0; if (randCount != 0) { RNG_FileUpdate(randfile, randCount); } else { RNG_FileForRNG(randfile); } } /* pass other files through */ for (cp = files; *cp; cp++) RNG_FileForRNG(*cp); #if defined(BSDI) || defined(FREEBSD) || defined(NETBSD) || defined(OPENBSD) || defined(DARWIN) || defined(LINUX) || defined(HPUX) if (bytes) return; #endif #ifdef SOLARIS if (!bytes) { /* On Solaris 8, /dev/urandom isn't available, so we use libkstat. */ PRUint32 kstat_bytes = 0; if (SECSuccess != RNG_kstat(&kstat_bytes)) { PORT_Assert(0); } bytes += kstat_bytes; PORT_Assert(bytes); } #endif } #define TOTAL_FILE_LIMIT 1000000 /* one million */ size_t RNG_FileUpdate(const char *fileName, size_t limit) { FILE *file; int fd; int bytes; size_t fileBytes = 0; struct stat stat_buf; unsigned char buffer[BUFSIZ]; static size_t totalFileBytes = 0; /* suppress valgrind warnings due to holes in struct stat */ memset(&stat_buf, 0, sizeof(stat_buf)); if (stat((char *)fileName, &stat_buf) < 0) return fileBytes; RNG_RandomUpdate(&stat_buf, sizeof(stat_buf)); file = fopen(fileName, "r"); if (file != NULL) { /* Read from the underlying file descriptor directly to bypass stdio * buffering and avoid reading more bytes than we need from * /dev/urandom. NOTE: we can't use fread with unbuffered I/O because * fread may return EOF in unbuffered I/O mode on Android. * * Moreover, we read into a buffer of size BUFSIZ, so buffered I/O * has no performance advantage. */ fd = fileno(file); /* 'file' was just opened, so this should not fail. */ PORT_Assert(fd != -1); while (limit > fileBytes && fd != -1) { bytes = PR_MIN(sizeof buffer, limit - fileBytes); bytes = read(fd, buffer, bytes); if (bytes <= 0) break; RNG_RandomUpdate(buffer, bytes); fileBytes += bytes; totalFileBytes += bytes; /* after TOTAL_FILE_LIMIT has been reached, only read in first ** buffer of data from each subsequent file. */ if (totalFileBytes > TOTAL_FILE_LIMIT) break; } fclose(file); } /* * Pass yet another snapshot of our highest resolution clock into * the hash function. */ bytes = RNG_GetNoise(buffer, sizeof(buffer)); RNG_RandomUpdate(buffer, bytes); return fileBytes; } void RNG_FileForRNG(const char *fileName) { RNG_FileUpdate(fileName, TOTAL_FILE_LIMIT); } #define _POSIX_PTHREAD_SEMANTICS #include PRBool ReadFileOK(char *dir, char *file) { struct stat stat_buf; char filename[PATH_MAX]; int count = snprintf(filename, sizeof filename, "%s/%s", dir, file); if (count <= 0) { return PR_FALSE; /* name too long, can't read it anyway */ } if (stat(filename, &stat_buf) < 0) return PR_FALSE; /* can't stat, probably can't read it then as well */ return S_ISREG(stat_buf.st_mode) ? PR_TRUE : PR_FALSE; } size_t RNG_SystemRNG(void *dest, size_t maxLen) { FILE *file; int fd; int bytes; size_t fileBytes = 0; unsigned char *buffer = dest; file = fopen("/dev/urandom", "r"); if (file == NULL) { PORT_SetError(SEC_ERROR_NEED_RANDOM); return 0; } /* Read from the underlying file descriptor directly to bypass stdio * buffering and avoid reading more bytes than we need from /dev/urandom. * NOTE: we can't use fread with unbuffered I/O because fread may return * EOF in unbuffered I/O mode on Android. */ fd = fileno(file); /* 'file' was just opened, so this should not fail. */ PORT_Assert(fd != -1); while (maxLen > fileBytes && fd != -1) { bytes = maxLen - fileBytes; bytes = read(fd, buffer, bytes); if (bytes <= 0) break; fileBytes += bytes; buffer += bytes; } fclose(file); if (fileBytes != maxLen) { PORT_SetError(SEC_ERROR_NEED_RANDOM); /* system RNG failed */ fileBytes = 0; } return fileBytes; }