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privsep.c
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privsep.c
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/*
* Copyright (c) 2004,2005 Damien Miller <[email protected]>
*
* Permission to use, copy, modify, and 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
*/
#include "flowd-common.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <stdio.h>
#include <syslog.h>
#include <fcntl.h>
#include <errno.h>
#include <pwd.h>
#include <grp.h>
#include <netdb.h>
#include "flowd.h"
#include "privsep.h"
#include "atomicio.h"
RCSID("$Id$");
#ifndef offsetof
# define offsetof(type, member) ((size_t) &((type *)0)->member)
#endif
static sig_atomic_t child_exited = 0;
static pid_t child_pid = -1;
static int monitor_to_child_sock = -1;
#define C2M_MSG_OPEN_LOG 1 /* send: nothing ret: fdpass */
#define C2M_MSG_OPEN_SOCKET 2 /* send: nothing ret: fdpass */
#define C2M_MSG_RECONFIGURE 3 /* send: nothing ret: conf+fdpass */
/* Utility functions */
static char *
privsep_read_string(int fd, int nullok)
{
size_t len;
char buf[8192], *ret;
if (atomicio(read, fd, &len, sizeof(len)) != sizeof(len))
logerrx("%s: read len", __func__);
if (nullok && len == 0)
return (NULL);
if (len <= 0 || len >= sizeof(buf))
logerrx("%s: silly len: %zu", __func__, len);
if (atomicio(read, fd, buf, len) != len) {
logitm(LOG_ERR, "%s: read str", __func__);
return (NULL);
}
buf[len] = '\0';
if ((ret = strdup(buf)) == NULL)
logit(LOG_ERR, "%s: strdup failed", __func__);
return (ret);
}
static int
privsep_write_string(int fd, char *s, int nullok)
{
size_t len;
if (s == NULL) {
if (!nullok)
logerrx("%s: s == NULL", s);
len = 0;
} else if ((len = strlen(s)) <= 0) {
logit(LOG_ERR, "%s: silly len: %zu", __func__, len);
return (-1);
}
if (atomicio(vwrite, fd, &len, sizeof(len)) != sizeof(len)) {
logitm(LOG_ERR, "%s: write len", __func__);
return (-1);
}
if (len > 0 && atomicio(vwrite, fd, s, len) != len) {
logitm(LOG_ERR, "%s: write(str)", __func__);
return (-1);
}
return (0);
}
static int
write_pid_file(const char *path)
{
FILE *pid_file;
if ((pid_file = fopen(path, "w")) == NULL) {
logitm(LOG_ERR, "fopen(%s)", path);
return (-1);
}
if (fprintf(pid_file, "%ld\n", (long)getpid()) == -1) {
logitm(LOG_ERR, "fprintf(%s)", path);
return (-1);
}
fclose(pid_file);
return (0);
}
int
open_sender(struct xaddr *addr, u_int16_t port, size_t bufsiz)
{
int fd;
struct sockaddr_storage ss;
socklen_t slen = sizeof(ss);
if (addr_xaddr_to_sa(addr, (struct sockaddr *)&ss, &slen, port) == -1) {
logit(LOG_ERR, "(%s): %s", __func__, "addr_xaddr_to_sa");
return (-1);
}
if ((fd = socket(addr->af, SOCK_DGRAM, 0)) == -1) {
logitm(LOG_ERR, "(%s): %s", __func__, "socket");
return (-1);
}
if (connect(fd, (struct sockaddr *)&ss, slen) == -1) {
logitm(LOG_ERR, "connect");
return (-1);
}
logit(LOG_DEBUG, "Sender for [%s]:%d fd = %d", addr_ntop_buf(addr),
port, fd);
return (fd);
}
int
open_listener(struct xaddr *addr, u_int16_t port, size_t bufsiz,
struct join_groups *groups)
{
int fd, fl, i, orig;
struct sockaddr_storage ss;
socklen_t slen = sizeof(ss);
struct join_group *jg;
struct ip_mreq v4mreq;
struct ipv6_mreq v6mreq;
if (addr_xaddr_to_sa(addr, (struct sockaddr *)&ss, &slen, port) == -1) {
logit(LOG_ERR, "addr_xaddr_to_sa");
return (-1);
}
if ((fd = socket(addr->af, SOCK_DGRAM, 0)) == -1) {
logitm(LOG_ERR, "socket");
return (-1);
}
/* Set non-blocking */
if ((fl = fcntl(fd, F_GETFL, 0)) == -1) {
logitm(LOG_ERR, "fcntl(%d, F_GETFL, 0)", fd);
return (-1);
}
fl |= O_NONBLOCK;
if (fcntl(fd, F_SETFL, fl) == -1) {
logitm(LOG_ERR, "fcntl(%d, F_SETFL, O_NONBLOCK)", fd);
return (-1);
}
#ifdef IPV6_V6ONLY
/* Set v6-only for AF_INET6 sockets (no mapped address crap) */
fl = 1;
if (addr->af == AF_INET6 &&
setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &fl, sizeof(fl)) == -1) {
logitm(LOG_ERR, "setsockopt(IPV6_V6ONLY)");
return (-1);
}
#endif
if (bind(fd, (struct sockaddr *)&ss, slen) == -1) {
logitm(LOG_ERR, "bind");
return (-1);
}
logit(LOG_DEBUG, "Listener for [%s]:%d fd = %d", addr_ntop_buf(addr),
port, fd);
/*
* Crank up socket receive buffer size to cope with bursts of flows
* If the config doesn't contain an explicit buffer size, we
* fall back to guessing.
*/
slen = sizeof(fl);
if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &orig, &slen) == 0) {
if (bufsiz > 0) {
fl = bufsiz;
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &fl,
sizeof(fl)) == 0) {
logit(LOG_DEBUG, "Adjusted socket receive "
"buffer from %d to %d", orig, fl);
} else
logerr("%s: setsockopt(SO_RCVBUF)", __func__);
} else {
for (i = 3; i >= 1; i--) {
fl = (1024 * 64) << i;
if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &fl,
sizeof(fl)) == 0) {
logit(LOG_DEBUG, "Adjusted socket receive "
"buffer from %d to %d", orig, fl);
break;
} else if (i == 1)
logitm(LOG_DEBUG, "setsockopt(SO_RCVBUF)");
}
}
}
/* Shrink send buffer, because we never use it */
fl = 1024;
logit(LOG_DEBUG, "Setting socket send buf to %d", fl);
if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &fl, sizeof(fl)) == -1)
logitm(LOG_DEBUG, "setsockopt(SO_SNDBUF)");
TAILQ_FOREACH(jg, groups, entry) {
if (jg->addr.af != addr->af)
continue;
logit(LOG_DEBUG, "Multicast join on fd %d to [%s]", fd,
addr_ntop_buf(&jg->addr));
switch (addr->af) {
case AF_INET:
bzero(&v4mreq, sizeof(v4mreq));
v4mreq.imr_multiaddr = jg->addr.v4;
v4mreq.imr_interface.s_addr = INADDR_ANY;
if (setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
&v4mreq, sizeof(v4mreq)) == -1)
logitm(LOG_ERR, "setsockopt(IP_ADD_MEMBERSHIP)");
/* non-fatal for now */
break;
case AF_INET6:
bzero(&v6mreq, sizeof(v6mreq));
v6mreq.ipv6mr_multiaddr = jg->addr.v6;
v6mreq.ipv6mr_interface = jg->addr.scope_id;
if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP,
&v6mreq, sizeof(v6mreq)) == -1)
logitm(LOG_ERR, "setsockopt(IPV6_JOIN_GROUP)");
/* non-fatal for now */
break;
}
}
return (fd);
}
static void
replace_conf(struct flowd_config *conf, struct flowd_config *newconf)
{
struct listen_addr *la;
struct filter_rule *fr;
struct allowed_device *ad;
struct join_group *jg;
if (conf->log_file != NULL)
free(conf->log_file);
if (conf->log_socket != NULL)
free(conf->log_socket);
free(conf->pid_file);
while ((la = TAILQ_FIRST(&conf->listen_addrs)) != NULL) {
if (la->fd != -1)
close(la->fd);
TAILQ_REMOVE(&conf->listen_addrs, la, entry);
free(la);
}
while ((fr = TAILQ_FIRST(&conf->filter_list)) != NULL) {
TAILQ_REMOVE(&conf->filter_list, fr, entry);
free(fr);
}
while ((ad = TAILQ_FIRST(&conf->allowed_devices)) != NULL) {
TAILQ_REMOVE(&conf->allowed_devices, ad, entry);
free(ad);
}
while ((jg = TAILQ_FIRST(&conf->join_groups)) != NULL) {
TAILQ_REMOVE(&conf->join_groups, jg, entry);
free(jg);
}
memcpy(conf, newconf, sizeof(*conf));
TAILQ_INIT(&conf->listen_addrs);
TAILQ_INIT(&conf->filter_list);
TAILQ_INIT(&conf->allowed_devices);
TAILQ_INIT(&conf->join_groups);
while ((la = TAILQ_LAST(&newconf->listen_addrs, listen_addrs)) != NULL) {
TAILQ_REMOVE(&newconf->listen_addrs, la, entry);
TAILQ_INSERT_HEAD(&conf->listen_addrs, la, entry);
}
while ((fr = TAILQ_LAST(&newconf->filter_list, filter_list)) != NULL) {
TAILQ_REMOVE(&newconf->filter_list, fr, entry);
TAILQ_INSERT_HEAD(&conf->filter_list, fr, entry);
}
while ((ad = TAILQ_LAST(&newconf->allowed_devices,
allowed_devices)) != NULL) {
TAILQ_REMOVE(&newconf->allowed_devices, ad, entry);
TAILQ_INSERT_HEAD(&conf->allowed_devices, ad, entry);
}
while ((jg = TAILQ_LAST(&newconf->join_groups, join_groups)) != NULL) {
TAILQ_REMOVE(&newconf->join_groups, jg, entry);
TAILQ_INSERT_HEAD(&conf->join_groups, jg, entry);
}
bzero(newconf, sizeof(*newconf));
}
static int
recv_config(int fd, struct flowd_config *conf)
{
u_int n, i;
struct listen_addr *la;
struct forward_addr *fa;
struct filter_rule *fr;
struct allowed_device *ad;
struct join_group *jg;
struct flowd_config newconf;
logit(LOG_DEBUG, "%s: entering fd = %d", __func__, fd);
bzero(&newconf, sizeof(newconf));
TAILQ_INIT(&newconf.listen_addrs);
TAILQ_INIT(&newconf.forward_addrs);
TAILQ_INIT(&newconf.filter_list);
TAILQ_INIT(&newconf.allowed_devices);
TAILQ_INIT(&newconf.join_groups);
logit(LOG_DEBUG, "%s: ready to receive config", __func__);
newconf.log_file = privsep_read_string(fd, 1);
newconf.log_socket = privsep_read_string(fd, 1);
if (atomicio(read, fd, &newconf.log_socket_bufsiz,
sizeof(newconf.log_socket_bufsiz)) !=
sizeof(newconf.log_socket_bufsiz)) {
logitm(LOG_ERR, "%s: read(conf.log_socket_bufsiz)", __func__);
return (-1);
}
if ((newconf.pid_file = privsep_read_string(fd, 0)) == NULL) {
logit(LOG_ERR, "%s: Couldn't read conf.pid_file", __func__);
return (-1);
}
if (atomicio(read, fd, &newconf.store_mask,
sizeof(newconf.store_mask)) != sizeof(newconf.store_mask)) {
logitm(LOG_ERR, "%s: read(conf.store_mask)", __func__);
return (-1);
}
if (atomicio(read, fd, &newconf.opts, sizeof(newconf.opts)) !=
sizeof(newconf.opts)) {
logitm(LOG_ERR, "%s: read(conf.opts)", __func__);
return (-1);
}
/* Read Listen Addrs */
if (atomicio(read, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: read(num listen_addrs)", __func__);
return (-1);
}
if (n == 0 || n > 8192) {
logit(LOG_ERR, "%s: silly number of listen_addrs: %d",
__func__, n);
return (-1);
}
for (i = 0; i < n; i++) {
if ((la = calloc(1, sizeof(*la))) == NULL) {
logit(LOG_ERR, "%s: calloc", __func__);
return (-1);
}
if (atomicio(read, fd, la, sizeof(*la)) != sizeof(*la)) {
logitm(LOG_ERR, "%s: read(listen_addr)", __func__);
return (-1);
}
if (la->fd != -1 && (la->fd = receive_fd(fd)) == -1)
return (-1);
TAILQ_INSERT_TAIL(&newconf.listen_addrs, la, entry);
}
/* Read Forward Addrs */
if (atomicio(read, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: read(num forward_addrs)", __func__);
return (-1);
}
if (n < 0 || n > 8192) {
logit(LOG_ERR, "%s: silly number of forward_addrs: %d",
__func__, n);
return (-1);
}
for (i = 0; i < n; i++) {
if ((fa = calloc(1, sizeof(*fa))) == NULL) {
logit(LOG_ERR, "%s: calloc", __func__);
return (-1);
}
if (atomicio(read, fd, fa, sizeof(*fa)) != sizeof(*fa)) {
logitm(LOG_ERR, "%s: read(forward_addr)", __func__);
return (-1);
}
if (fa->fd != -1 && (fa->fd = receive_fd(fd)) == -1)
return (-1);
logit(LOG_DEBUG, "%s: read forward addr %s.", __func__,
addr_ntop_buf(&fa->addr));
TAILQ_INSERT_TAIL(&newconf.forward_addrs, fa, entry);
}
/* Read Filter Rules */
if (atomicio(read, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: read(num filter_rules)", __func__);
return (-1);
}
if (n > 1024*1024) {
logit(LOG_ERR, "%s: silly number of filter_rules: %d",
__func__, n);
return (-1);
}
for (i = 0; i < n; i++) {
if ((fr = calloc(1, sizeof(*fr))) == NULL) {
logit(LOG_ERR, "%s: calloc", __func__);
return (-1);
}
if (atomicio(read, fd, fr, sizeof(*fr)) != sizeof(*fr)) {
logitm(LOG_ERR, "%s: read(filter_rule)", __func__);
return (-1);
}
TAILQ_INSERT_TAIL(&newconf.filter_list, fr, entry);
}
/* Read Allowed Devices */
if (atomicio(read, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: read(num allowed_devices)", __func__);
return (-1);
}
if (n > 1024*1024) {
logit(LOG_ERR, "%s: silly number of allowed_devices: %d",
__func__, n);
return (-1);
}
for (i = 0; i < n; i++) {
if ((ad = calloc(1, sizeof(*ad))) == NULL) {
logit(LOG_ERR, "%s: calloc", __func__);
return (-1);
}
if (atomicio(read, fd, ad, sizeof(*ad)) != sizeof(*ad)) {
logitm(LOG_ERR, "%s: read(allowed_device)", __func__);
return (-1);
}
TAILQ_INSERT_TAIL(&newconf.allowed_devices, ad, entry);
}
/* Read multicast join groups */
if (atomicio(read, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: read(num join_groups)", __func__);
return (-1);
}
if (n > 1024*1024) {
logit(LOG_ERR, "%s: silly number of join_groups: %d",
__func__, n);
return (-1);
}
for (i = 0; i < n; i++) {
if ((jg = calloc(1, sizeof(*jg))) == NULL) {
logit(LOG_ERR, "%s: calloc", __func__);
return (-1);
}
if (atomicio(read, fd, jg, sizeof(*jg)) != sizeof(*jg)) {
logitm(LOG_ERR, "%s: read(join_group)", __func__);
return (-1);
}
TAILQ_INSERT_TAIL(&newconf.join_groups, jg, entry);
}
replace_conf(conf, &newconf);
return (0);
}
static int
send_config(int fd, struct flowd_config *conf)
{
u_int n;
struct listen_addr *la;
struct forward_addr *fa;
struct filter_rule *fr;
struct allowed_device *ad;
struct join_group *jg;
logit(LOG_DEBUG, "%s: entering fd = %d", __func__, fd);
if (privsep_write_string(fd, conf->log_file, 1) == -1) {
logit(LOG_ERR, "%s: Couldn't write conf.log_file", __func__);
return (-1);
}
if (privsep_write_string(fd, conf->log_socket, 1) == -1) {
logit(LOG_ERR, "%s: Couldn't write conf.log_socket", __func__);
return (-1);
}
if (atomicio(vwrite, fd, &conf->log_socket_bufsiz,
sizeof(conf->log_socket_bufsiz)) !=
sizeof(conf->log_socket_bufsiz)) {
logitm(LOG_ERR, "%s: write(conf.log_socket_bufsiz)", __func__);
return (-1);
}
if (privsep_write_string(fd, conf->pid_file, 0) == -1) {
logit(LOG_ERR, "%s: Couldn't write conf.pid_file", __func__);
return (-1);
}
if (atomicio(vwrite, fd, &conf->store_mask,
sizeof(conf->store_mask)) != sizeof(conf->store_mask)) {
logitm(LOG_ERR, "%s: write(conf.store_mask)", __func__);
return (-1);
}
if (atomicio(vwrite, fd, &conf->opts,
sizeof(conf->opts)) != sizeof(conf->opts)) {
logitm(LOG_ERR, "%s: write(conf.opts)", __func__);
return (-1);
}
/* Write Listen Addrs */
n = 0;
TAILQ_FOREACH(la, &conf->listen_addrs, entry)
n++;
if (atomicio(vwrite, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: write(num listen_addrs)", __func__);
return (-1);
}
TAILQ_FOREACH(la, &conf->listen_addrs, entry) {
if (atomicio(vwrite, fd, la, sizeof(*la)) != sizeof(*la)) {
logitm(LOG_ERR, "%s: write(listen_addr)", __func__);
return (-1);
}
if (la->fd != -1 && send_fd(fd, la->fd) == -1)
return (-1);
}
/* Write Forward Addrs */
n = 0;
TAILQ_FOREACH(fa, &conf->forward_addrs, entry)
n++;
if (atomicio(vwrite, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: write(num forward_addrs)", __func__);
return (-1);
}
TAILQ_FOREACH(fa, &conf->forward_addrs, entry) {
if (atomicio(vwrite, fd, fa, sizeof(*fa)) != sizeof(*fa)) {
logitm(LOG_ERR, "%s: write(forward_addr)", __func__);
return (-1);
}
if (fa->fd != -1 && send_fd(fd, fa->fd) == -1)
return (-1);
}
/* Write Filter Rules */
n = 0;
TAILQ_FOREACH(fr, &conf->filter_list, entry)
n++;
if (atomicio(vwrite, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: write(num filter_rules)", __func__);
return (-1);
}
TAILQ_FOREACH(fr, &conf->filter_list, entry) {
if (atomicio(vwrite, fd, fr, sizeof(*fr)) != sizeof(*fr)) {
logitm(LOG_ERR, "%s: write(filter_rule)", __func__);
return (-1);
}
}
/* Write Allowed Devices */
n = 0;
TAILQ_FOREACH(ad, &conf->allowed_devices, entry)
n++;
if (atomicio(vwrite, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: write(num allowed_devices)", __func__);
return (-1);
}
TAILQ_FOREACH(ad, &conf->allowed_devices, entry) {
if (atomicio(vwrite, fd, ad, sizeof(*ad)) != sizeof(*ad)) {
logitm(LOG_ERR, "%s: write(allowed_devices)", __func__);
return (-1);
}
}
/* Write Multicast join groups */
n = 0;
TAILQ_FOREACH(jg, &conf->join_groups, entry)
n++;
if (atomicio(vwrite, fd, &n, sizeof(n)) != sizeof(n)) {
logitm(LOG_ERR, "%s: write(num join_group)", __func__);
return (-1);
}
TAILQ_FOREACH(jg, &conf->join_groups, entry) {
if (atomicio(vwrite, fd, jg, sizeof(*jg)) != sizeof(*jg)) {
logitm(LOG_ERR, "%s: write(join_group)", __func__);
return (-1);
}
}
logit(LOG_DEBUG, "%s: done", __func__);
return (0);
}
static int
drop_privs(struct passwd *pw, int do_chroot)
{
logit(LOG_DEBUG, "drop_privs: dropping privs %s chroot",
do_chroot ? "with" : "without");
if (setsid() == -1) {
logitm(LOG_ERR, "setsid");
return (-1);
}
if (do_chroot) {
if (chdir(pw->pw_dir) == -1) {
logitm(LOG_ERR, "chdir(%s)", pw->pw_dir);
return (-1);
}
if (chroot(pw->pw_dir) == -1) {
logitm(LOG_ERR, "chroot(%s)", pw->pw_dir);
return (-1);
}
}
if (chdir("/") == -1) {
logitm(LOG_ERR, "chdir(/)");
return (-1);
}
if (setgroups(1, &pw->pw_gid) == -1) {
logitm(LOG_ERR, "setgroups");
return (-1);
}
#if defined(HAVE_SETRESGID)
if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {
logitm(LOG_ERR, "setresgid");
return (-1);
}
#elif defined(HAVE_SETREGID)
if (setregid(pw->pw_gid, pw->pw_gid) == -1) {
logitm(LOG_ERR, "setregid");
return (-1);
}
#else
# error No suitable setgid function found
#endif
#if defined(HAVE_SETRESUID)
if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) {
logitm(LOG_ERR, "setresuid");
return (-1);
}
#elif defined(HAVE_SETREUID)
if (setreuid(pw->pw_uid, pw->pw_uid) == -1) {
logitm(LOG_ERR, "setreuid");
return (-1);
}
#else
# error No suitable setuid function found
#endif
return (0);
}
static int
child_get_config(const char *path, struct flowd_config *conf)
{
int s[2], ok, status;
pid_t ccpid;
void (*oldsigchld)(int);
FILE *cfg;
struct passwd *pw = NULL;
struct flowd_config newconf = {
NULL, NULL, 0, NULL, 0, 0,
TAILQ_HEAD_INITIALIZER(newconf.listen_addrs),
TAILQ_HEAD_INITIALIZER(newconf.forward_addrs),
TAILQ_HEAD_INITIALIZER(newconf.filter_list),
TAILQ_HEAD_INITIALIZER(newconf.allowed_devices),
TAILQ_HEAD_INITIALIZER(newconf.join_groups)
};
logit(LOG_DEBUG, "%s: entering", __func__);
if ((conf->opts & FLOWD_OPT_INSECURE) == 0 &&
(pw = getpwnam(PRIVSEP_USER)) == NULL) {
logit(LOG_ERR, "Privilege separation user %s doesn't exist",
PRIVSEP_USER);
return(-1);
}
endpwent();
if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, s) == -1) {
logitm(LOG_ERR, "%s: socketpair", __func__);
return (-1);
}
oldsigchld = signal(SIGCHLD, SIG_DFL);
switch (ccpid = fork()) {
case -1:
logitm(LOG_ERR, "%s: fork", __func__);
return (-1);
case 0: /* Child */
close(s[0]);
setproctitle("config");
if ((cfg = fopen(path, "r")) == NULL) {
logitm(LOG_ERR, "fopen(%s)", path);
exit(1);
}
if ((conf->opts & FLOWD_OPT_INSECURE) == 0 &&
drop_privs(pw, 0) == -1)
exit(1);
ok = (parse_config(path, cfg, &newconf, 0) == 0);
fclose(cfg);
if (atomicio(vwrite, s[1], &ok, sizeof(ok)) != sizeof(ok)) {
logitm(LOG_ERR, "%s: write(ok)", __func__);
exit(1);
}
if (!ok)
exit(1);
if (send_config(s[1], &newconf) == -1)
exit(1);
logit(LOG_DEBUG, "%s: child config done", __func__);
exit(0);
default: /* Parent */
close(s[1]);
break;
}
/* Parent */
if (atomicio(read, s[0], &ok, sizeof(ok)) != sizeof(ok)) {
logitm(LOG_ERR, "%s: read(ok)", __func__);
return (-1);
}
if (!ok)
return (-1);
if (recv_config(s[0], conf) == -1)
return (-1);
close(s[0]);
if (waitpid(ccpid, &status, 0) == -1) {
logitm(LOG_ERR, "%s: waitpid", __func__);
return (-1);
}
if (!WIFEXITED(status)) {
logit(LOG_ERR, "child exited abnormally");
return (-1);
}
if (WEXITSTATUS(status) != 0) {
logit(LOG_ERR, "child exited with status %d",
WEXITSTATUS(status));
return (-1);
}
signal(SIGCHLD, oldsigchld);
return (0);
}
int
read_config(const char *path, struct flowd_config *conf)
{
u_int32_t opts;
logit(LOG_DEBUG, "%s: entering", __func__);
/* Preserve options not set in config file */
opts = conf->opts &
(FLOWD_OPT_DONT_FORK|FLOWD_OPT_VERBOSE|FLOWD_OPT_INSECURE);
if (child_get_config(path, conf))
return (-1);
conf->opts |= opts;
return (0);
}
/* Client functions */
int
client_open_log(int monitor_fd)
{
int fd = -1;
u_int msg = C2M_MSG_OPEN_LOG;
logit(LOG_DEBUG, "%s: entering", __func__);
if (atomicio(vwrite, monitor_fd, &msg, sizeof(msg)) != sizeof(msg)) {
logitm(LOG_ERR, "%s: write", __func__);
return (-1);
}
if ((fd = receive_fd(monitor_fd)) == -1)
return (-1);
return (fd);
}
int
client_open_socket(int monitor_fd)
{
int fd = -1;
u_int msg = C2M_MSG_OPEN_SOCKET;
logit(LOG_DEBUG, "%s: entering", __func__);
if (atomicio(vwrite, monitor_fd, &msg, sizeof(msg)) != sizeof(msg)) {
logitm(LOG_ERR, "%s: write", __func__);
return (-1);
}
if ((fd = receive_fd(monitor_fd)) == -1)
return (-1);
return (fd);
}
int
client_reconfigure(int monitor_fd, struct flowd_config *conf)
{
u_int msg = C2M_MSG_RECONFIGURE, ok;
struct listen_addr *la;
logit(LOG_DEBUG, "%s: entering", __func__);
TAILQ_FOREACH(la, &conf->listen_addrs, entry) {
if (la->fd != -1)
close(la->fd);
la->fd = -1;
}
if (atomicio(vwrite, monitor_fd, &msg, sizeof(msg)) != sizeof(msg)) {
logitm(LOG_ERR, "%s: write", __func__);
return (-1);
}
if (atomicio(read, monitor_fd, &ok, sizeof(ok)) != sizeof(ok)) {
logitm(LOG_ERR, "%s: read(ok)", __func__);
return (-1);
}
if (!ok) {
logit(LOG_ERR, "New config is invalid");
return (-1);
}
if (recv_config(monitor_fd, conf) == -1)
return (-1);
logit(LOG_DEBUG, "%s: done", __func__);
return (0);
}
/* Client answer functions */
static int
answer_open_log(struct flowd_config *conf, int client_fd)
{
int fd;
logit(LOG_DEBUG, "%s: entering", __func__);
if (conf->log_file == NULL)
logerrx("%s: attempt to open NULL log", __func__);
fd = open(conf->log_file, O_RDWR|O_APPEND|O_CREAT, 0600);
if (fd == -1) {
logitm(LOG_ERR, "%s: open", __func__);
return (-1);
}
if (send_fd(client_fd, fd) == -1)
return (-1);
close(fd);
return (0);
}
static int
answer_open_socket(struct flowd_config *conf, int client_fd)
{
int fd, slen, orig;
struct sockaddr_un to;
socklen_t tolen;
logit(LOG_DEBUG, "%s: entering", __func__);
if (conf->log_socket == NULL)
logerrx("%s: attempt to open NULL log", __func__);
if ((fd = socket(AF_UNIX, SOCK_DGRAM, 0)) == -1) {
logitm(LOG_ERR, "%s: socket", __func__);
return (-1);
}
bzero(&to, sizeof(to));
if (strlcpy(to.sun_path, conf->log_socket,
sizeof(to.sun_path)) >= sizeof(to.sun_path))
logerrx("Log socket path too long");
to.sun_family = AF_UNIX;
tolen = offsetof(struct sockaddr_un, sun_path) +
strlen(conf->log_socket) + 1;
#ifdef SOCK_HAS_LEN
to.sun_len = tolen;
#endif
if (connect(fd, (struct sockaddr *)&to, tolen) == -1) {
logitm(LOG_ERR, "connect to logsock");
return (-1);
}
slen = sizeof(orig);
if (conf->log_socket_bufsiz > 0 &&
getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &orig, &slen) == 0) {
if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF,
&conf->log_socket_bufsiz,
sizeof(conf->log_socket_bufsiz)) == 0) {
logit(LOG_DEBUG, "Adjusted log_socket send "
"buffer from %d to %zd", orig,
conf->log_socket_bufsiz);
} else
logerr("%s: setsockopt(SO_SNDBUF)", __func__);
}
if (send_fd(client_fd, fd) == -1)
return (-1);
close(fd);
return (0);
}
static int
answer_reconfigure(struct flowd_config *conf, int client_fd,
const char *config_path)
{
u_int ok, rewrite_pidfile;
struct flowd_config newconf;
struct listen_addr *la;
struct forward_addr *fa;
bzero(&newconf, sizeof(newconf));
TAILQ_INIT(&newconf.listen_addrs);
TAILQ_INIT(&newconf.filter_list);
TAILQ_INIT(&newconf.allowed_devices);
TAILQ_INIT(&newconf.join_groups);
/* Transcribe flags not set in config file */
newconf.opts |= (conf->opts &
(FLOWD_OPT_DONT_FORK|FLOWD_OPT_VERBOSE|FLOWD_OPT_INSECURE));
logit(LOG_DEBUG, "%s: entering", __func__);
ok = 1;
if (read_config(config_path, &newconf) == -1) {
logit(LOG_ERR, "New config has errors");
ok = 0;
}
TAILQ_FOREACH(la, &newconf.listen_addrs, entry) {
if ((la->fd = open_listener(&la->addr, la->port, la->bufsiz,
&conf->join_groups)) == -1) {
logit(LOG_ERR, "Listener setup of [%s]:%d failed",
addr_ntop_buf(&la->addr), la->port);
ok = 0;
break;
}
}
logit(LOG_DEBUG, "%s: post listener open, ok = %d", __func__, ok);
TAILQ_FOREACH(fa, &newconf.forward_addrs, entry) {
if ((fa->fd = open_sender(&fa->addr, fa->port, fa->bufsiz)) == -1) {
logit(LOG_ERR, "Forwarder setup of [%s]:%d failed",
addr_ntop_buf(&fa->addr), fa->port);
ok = 0;
break;
}
}
logit(LOG_DEBUG, "%s: post forwarder open, ok = %d", __func__, ok);
if (atomicio(vwrite, client_fd, &ok, sizeof(ok)) != sizeof(ok)) {
logitm(LOG_ERR, "%s: write(ok)", __func__);
return (-1);
}
if (ok == 0)
return (-1);
if (send_config(client_fd, &newconf) == -1)
return (-1);