diff options
Diffstat (limited to 'contrib/bind9/lib/isc/unix/entropy.c')
-rw-r--r-- | contrib/bind9/lib/isc/unix/entropy.c | 604 |
1 files changed, 0 insertions, 604 deletions
diff --git a/contrib/bind9/lib/isc/unix/entropy.c b/contrib/bind9/lib/isc/unix/entropy.c deleted file mode 100644 index 9c422b5..0000000 --- a/contrib/bind9/lib/isc/unix/entropy.c +++ /dev/null @@ -1,604 +0,0 @@ -/* - * Copyright (C) 2004-2008, 2012 Internet Systems Consortium, Inc. ("ISC") - * Copyright (C) 2000-2003 Internet Software Consortium. - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* $Id: entropy.c,v 1.82 2008/12/01 23:47:45 tbox Exp $ */ - -/* \file unix/entropy.c - * \brief - * This is the system dependent part of the ISC entropy API. - */ - -#include <config.h> - -#include <sys/param.h> /* Openserver 5.0.6A and FD_SETSIZE */ -#include <sys/types.h> -#include <sys/time.h> -#include <sys/stat.h> -#include <sys/socket.h> -#include <sys/un.h> - -#ifdef HAVE_NANOSLEEP -#include <time.h> -#endif -#include <unistd.h> - -#include <isc/platform.h> -#include <isc/strerror.h> - -#ifdef ISC_PLATFORM_NEEDSYSSELECTH -#include <sys/select.h> -#endif - -#include "errno2result.h" - -/*% - * There is only one variable in the entropy data structures that is not - * system independent, but pulling the structure that uses it into this file - * ultimately means pulling several other independent structures here also to - * resolve their interdependencies. Thus only the problem variable's type - * is defined here. - */ -#define FILESOURCE_HANDLE_TYPE int - -typedef struct { - int handle; - enum { - isc_usocketsource_disconnected, - isc_usocketsource_connecting, - isc_usocketsource_connected, - isc_usocketsource_ndesired, - isc_usocketsource_wrote, - isc_usocketsource_reading - } status; - size_t sz_to_recv; -} isc_entropyusocketsource_t; - -#include "../entropy.c" - -static unsigned int -get_from_filesource(isc_entropysource_t *source, isc_uint32_t desired) { - isc_entropy_t *ent = source->ent; - unsigned char buf[128]; - int fd = source->sources.file.handle; - ssize_t n, ndesired; - unsigned int added; - - if (source->bad) - return (0); - - desired = desired / 8 + (((desired & 0x07) > 0) ? 1 : 0); - - added = 0; - while (desired > 0) { - ndesired = ISC_MIN(desired, sizeof(buf)); - n = read(fd, buf, ndesired); - if (n < 0) { - if (errno == EAGAIN || errno == EINTR) - goto out; - goto err; - } - if (n == 0) - goto err; - - entropypool_adddata(ent, buf, n, n * 8); - added += n * 8; - desired -= n; - } - goto out; - - err: - (void)close(fd); - source->sources.file.handle = -1; - source->bad = ISC_TRUE; - - out: - return (added); -} - -static unsigned int -get_from_usocketsource(isc_entropysource_t *source, isc_uint32_t desired) { - isc_entropy_t *ent = source->ent; - unsigned char buf[128]; - int fd = source->sources.usocket.handle; - ssize_t n = 0, ndesired; - unsigned int added; - size_t sz_to_recv = source->sources.usocket.sz_to_recv; - - if (source->bad) - return (0); - - desired = desired / 8 + (((desired & 0x07) > 0) ? 1 : 0); - - added = 0; - while (desired > 0) { - ndesired = ISC_MIN(desired, sizeof(buf)); - eagain_loop: - - switch ( source->sources.usocket.status ) { - case isc_usocketsource_ndesired: - buf[0] = ndesired; - if ((n = sendto(fd, buf, 1, 0, NULL, 0)) < 0) { - if (errno == EWOULDBLOCK || errno == EINTR || - errno == ECONNRESET) - goto out; - goto err; - } - INSIST(n == 1); - source->sources.usocket.status = - isc_usocketsource_wrote; - goto eagain_loop; - - case isc_usocketsource_connecting: - case isc_usocketsource_connected: - buf[0] = 1; - buf[1] = ndesired; - if ((n = sendto(fd, buf, 2, 0, NULL, 0)) < 0) { - if (errno == EWOULDBLOCK || errno == EINTR || - errno == ECONNRESET) - goto out; - goto err; - } - if (n == 1) { - source->sources.usocket.status = - isc_usocketsource_ndesired; - goto eagain_loop; - } - INSIST(n == 2); - source->sources.usocket.status = - isc_usocketsource_wrote; - /*FALLTHROUGH*/ - - case isc_usocketsource_wrote: - if (recvfrom(fd, buf, 1, 0, NULL, NULL) != 1) { - if (errno == EAGAIN) { - /* - * The problem of EAGAIN (try again - * later) is a major issue on HP-UX. - * Solaris actually tries the recvfrom - * call again, while HP-UX just dies. - * This code is an attempt to let the - * entropy pool fill back up (at least - * that's what I think the problem is.) - * We go to eagain_loop because if we - * just "break", then the "desired" - * amount gets borked. - */ -#ifdef HAVE_NANOSLEEP - struct timespec ts; - - ts.tv_sec = 0; - ts.tv_nsec = 1000000; - nanosleep(&ts, NULL); -#else - usleep(1000); -#endif - goto eagain_loop; - } - if (errno == EWOULDBLOCK || errno == EINTR) - goto out; - goto err; - } - source->sources.usocket.status = - isc_usocketsource_reading; - sz_to_recv = buf[0]; - source->sources.usocket.sz_to_recv = sz_to_recv; - if (sz_to_recv > sizeof(buf)) - goto err; - /*FALLTHROUGH*/ - - case isc_usocketsource_reading: - if (sz_to_recv != 0U) { - n = recv(fd, buf, sz_to_recv, 0); - if (n < 0) { - if (errno == EWOULDBLOCK || - errno == EINTR) - goto out; - goto err; - } - } else - n = 0; - break; - - default: - goto err; - } - - if ((size_t)n != sz_to_recv) - source->sources.usocket.sz_to_recv -= n; - else - source->sources.usocket.status = - isc_usocketsource_connected; - - if (n == 0) - goto out; - - entropypool_adddata(ent, buf, n, n * 8); - added += n * 8; - desired -= n; - } - goto out; - - err: - close(fd); - source->bad = ISC_TRUE; - source->sources.usocket.status = isc_usocketsource_disconnected; - source->sources.usocket.handle = -1; - - out: - return (added); -} - -/* - * Poll each source, trying to get data from it to stuff into the entropy - * pool. - */ -static void -fillpool(isc_entropy_t *ent, unsigned int desired, isc_boolean_t blocking) { - unsigned int added; - unsigned int remaining; - unsigned int needed; - unsigned int nsource; - isc_entropysource_t *source; - - REQUIRE(VALID_ENTROPY(ent)); - - needed = desired; - - /* - * This logic is a little strange, so an explanation is in order. - * - * If needed is 0, it means we are being asked to "fill to whatever - * we think is best." This means that if we have at least a - * partially full pool (say, > 1/4th of the pool) we probably don't - * need to add anything. - * - * Also, we will check to see if the "pseudo" count is too high. - * If it is, try to mix in better data. Too high is currently - * defined as 1/4th of the pool. - * - * Next, if we are asked to add a specific bit of entropy, make - * certain that we will do so. Clamp how much we try to add to - * (DIGEST_SIZE * 8 < needed < POOLBITS - entropy). - * - * Note that if we are in a blocking mode, we will only try to - * get as much data as we need, not as much as we might want - * to build up. - */ - if (needed == 0) { - REQUIRE(!blocking); - - if ((ent->pool.entropy >= RND_POOLBITS / 4) - && (ent->pool.pseudo <= RND_POOLBITS / 4)) - return; - - needed = THRESHOLD_BITS * 4; - } else { - needed = ISC_MAX(needed, THRESHOLD_BITS); - needed = ISC_MIN(needed, RND_POOLBITS); - } - - /* - * In any case, clamp how much we need to how much we can add. - */ - needed = ISC_MIN(needed, RND_POOLBITS - ent->pool.entropy); - - /* - * But wait! If we're not yet initialized, we need at least - * THRESHOLD_BITS - * of randomness. - */ - if (ent->initialized < THRESHOLD_BITS) - needed = ISC_MAX(needed, THRESHOLD_BITS - ent->initialized); - - /* - * Poll each file source to see if we can read anything useful from - * it. XXXMLG When where are multiple sources, we should keep a - * record of which one we last used so we can start from it (or the - * next one) to avoid letting some sources build up entropy while - * others are always drained. - */ - - added = 0; - remaining = needed; - if (ent->nextsource == NULL) { - ent->nextsource = ISC_LIST_HEAD(ent->sources); - if (ent->nextsource == NULL) - return; - } - source = ent->nextsource; - again_file: - for (nsource = 0; nsource < ent->nsources; nsource++) { - unsigned int got; - - if (remaining == 0) - break; - - got = 0; - - switch ( source->type ) { - case ENTROPY_SOURCETYPE_FILE: - got = get_from_filesource(source, remaining); - break; - - case ENTROPY_SOURCETYPE_USOCKET: - got = get_from_usocketsource(source, remaining); - break; - } - - added += got; - - remaining -= ISC_MIN(remaining, got); - - source = ISC_LIST_NEXT(source, link); - if (source == NULL) - source = ISC_LIST_HEAD(ent->sources); - } - ent->nextsource = source; - - if (blocking && remaining != 0) { - int fds; - - fds = wait_for_sources(ent); - if (fds > 0) - goto again_file; - } - - /* - * Here, if there are bits remaining to be had and we can block, - * check to see if we have a callback source. If so, call them. - */ - source = ISC_LIST_HEAD(ent->sources); - while ((remaining != 0) && (source != NULL)) { - unsigned int got; - - got = 0; - - if (source->type == ENTROPY_SOURCETYPE_CALLBACK) - got = get_from_callback(source, remaining, blocking); - - added += got; - remaining -= ISC_MIN(remaining, got); - - if (added >= needed) - break; - - source = ISC_LIST_NEXT(source, link); - } - - /* - * Mark as initialized if we've added enough data. - */ - if (ent->initialized < THRESHOLD_BITS) - ent->initialized += added; -} - -static int -wait_for_sources(isc_entropy_t *ent) { - isc_entropysource_t *source; - int maxfd, fd; - int cc; - fd_set reads; - fd_set writes; - - maxfd = -1; - FD_ZERO(&reads); - FD_ZERO(&writes); - - source = ISC_LIST_HEAD(ent->sources); - while (source != NULL) { - if (source->type == ENTROPY_SOURCETYPE_FILE) { - fd = source->sources.file.handle; - if (fd >= 0) { - maxfd = ISC_MAX(maxfd, fd); - FD_SET(fd, &reads); - } - } - if (source->type == ENTROPY_SOURCETYPE_USOCKET) { - fd = source->sources.usocket.handle; - if (fd >= 0) { - switch (source->sources.usocket.status) { - case isc_usocketsource_disconnected: - break; - case isc_usocketsource_connecting: - case isc_usocketsource_connected: - case isc_usocketsource_ndesired: - maxfd = ISC_MAX(maxfd, fd); - FD_SET(fd, &writes); - break; - case isc_usocketsource_wrote: - case isc_usocketsource_reading: - maxfd = ISC_MAX(maxfd, fd); - FD_SET(fd, &reads); - break; - } - } - } - source = ISC_LIST_NEXT(source, link); - } - - if (maxfd < 0) - return (-1); - - cc = select(maxfd + 1, &reads, &writes, NULL, NULL); - if (cc < 0) - return (-1); - - return (cc); -} - -static void -destroyfilesource(isc_entropyfilesource_t *source) { - (void)close(source->handle); -} - -static void -destroyusocketsource(isc_entropyusocketsource_t *source) { - close(source->handle); -} - -/* - * Make a fd non-blocking - */ -static isc_result_t -make_nonblock(int fd) { - int ret; - int flags; - char strbuf[ISC_STRERRORSIZE]; -#ifdef USE_FIONBIO_IOCTL - int on = 1; - - ret = ioctl(fd, FIONBIO, (char *)&on); -#else - flags = fcntl(fd, F_GETFL, 0); - flags |= PORT_NONBLOCK; - ret = fcntl(fd, F_SETFL, flags); -#endif - - if (ret == -1) { - isc__strerror(errno, strbuf, sizeof(strbuf)); - UNEXPECTED_ERROR(__FILE__, __LINE__, -#ifdef USE_FIONBIO_IOCTL - "ioctl(%d, FIONBIO, &on): %s", fd, -#else - "fcntl(%d, F_SETFL, %d): %s", fd, flags, -#endif - strbuf); - - return (ISC_R_UNEXPECTED); - } - - return (ISC_R_SUCCESS); -} - -isc_result_t -isc_entropy_createfilesource(isc_entropy_t *ent, const char *fname) { - int fd; - struct stat _stat; - isc_boolean_t is_usocket = ISC_FALSE; - isc_boolean_t is_connected = ISC_FALSE; - isc_result_t ret; - isc_entropysource_t *source; - - REQUIRE(VALID_ENTROPY(ent)); - REQUIRE(fname != NULL); - - LOCK(&ent->lock); - - if (stat(fname, &_stat) < 0) { - ret = isc__errno2result(errno); - goto errout; - } - /* - * Solaris 2.5.1 does not have support for sockets (S_IFSOCK), - * but it does return type S_IFIFO (the OS believes that - * the socket is a fifo). This may be an issue if we tell - * the program to look at an actual FIFO as its source of - * entropy. - */ -#if defined(S_ISSOCK) - if (S_ISSOCK(_stat.st_mode)) - is_usocket = ISC_TRUE; -#endif -#if defined(S_ISFIFO) && defined(sun) - if (S_ISFIFO(_stat.st_mode)) - is_usocket = ISC_TRUE; -#endif - if (is_usocket) - fd = socket(PF_UNIX, SOCK_STREAM, 0); - else - fd = open(fname, O_RDONLY | PORT_NONBLOCK, 0); - - if (fd < 0) { - ret = isc__errno2result(errno); - goto errout; - } - - ret = make_nonblock(fd); - if (ret != ISC_R_SUCCESS) - goto closefd; - - if (is_usocket) { - struct sockaddr_un sname; - - memset(&sname, 0, sizeof(sname)); - sname.sun_family = AF_UNIX; - strlcpy(sname.sun_path, fname, sizeof(sname.sun_path)); -#ifdef ISC_PLATFORM_HAVESALEN -#if !defined(SUN_LEN) -#define SUN_LEN(su) \ - (sizeof(*(su)) - sizeof((su)->sun_path) + strlen((su)->sun_path)) -#endif - sname.sun_len = SUN_LEN(&sname); -#endif - - if (connect(fd, (struct sockaddr *) &sname, - sizeof(struct sockaddr_un)) < 0) { - if (errno != EINPROGRESS) { - ret = isc__errno2result(errno); - goto closefd; - } - } else - is_connected = ISC_TRUE; - } - - source = isc_mem_get(ent->mctx, sizeof(isc_entropysource_t)); - if (source == NULL) { - ret = ISC_R_NOMEMORY; - goto closefd; - } - - /* - * From here down, no failures can occur. - */ - source->magic = SOURCE_MAGIC; - source->ent = ent; - source->total = 0; - source->bad = ISC_FALSE; - memset(source->name, 0, sizeof(source->name)); - ISC_LINK_INIT(source, link); - if (is_usocket) { - source->sources.usocket.handle = fd; - if (is_connected) - source->sources.usocket.status = - isc_usocketsource_connected; - else - source->sources.usocket.status = - isc_usocketsource_connecting; - source->sources.usocket.sz_to_recv = 0; - source->type = ENTROPY_SOURCETYPE_USOCKET; - } else { - source->sources.file.handle = fd; - source->type = ENTROPY_SOURCETYPE_FILE; - } - - /* - * Hook it into the entropy system. - */ - ISC_LIST_APPEND(ent->sources, source, link); - ent->nsources++; - - UNLOCK(&ent->lock); - return (ISC_R_SUCCESS); - - closefd: - (void)close(fd); - - errout: - UNLOCK(&ent->lock); - - return (ret); -} |