freebsd-skq/usr.sbin/iscsid/iscsid.c
pfg 7551d83c35 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

645 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2012 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Edward Tomasz Napierala under sponsorship
* from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/time.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/linker.h>
#include <sys/socket.h>
#include <sys/capsicum.h>
#include <sys/wait.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <libutil.h>
#include <netdb.h>
#include <signal.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "iscsid.h"
static volatile bool sigalrm_received = false;
static int nchildren = 0;
static void
usage(void)
{
fprintf(stderr, "usage: iscsid [-P pidfile][-d][-m maxproc][-t timeout]\n");
exit(1);
}
char *
checked_strdup(const char *s)
{
char *c;
c = strdup(s);
if (c == NULL)
log_err(1, "strdup");
return (c);
}
static void
resolve_addr(const struct connection *conn, const char *address,
struct addrinfo **ai, bool initiator_side)
{
struct addrinfo hints;
char *arg, *addr, *ch;
const char *port;
int error, colons = 0;
arg = checked_strdup(address);
if (arg[0] == '\0') {
fail(conn, "empty address");
log_errx(1, "empty address");
}
if (arg[0] == '[') {
/*
* IPv6 address in square brackets, perhaps with port.
*/
arg++;
addr = strsep(&arg, "]");
if (arg == NULL) {
fail(conn, "malformed address");
log_errx(1, "malformed address %s", address);
}
if (arg[0] == '\0') {
port = NULL;
} else if (arg[0] == ':') {
port = arg + 1;
} else {
fail(conn, "malformed address");
log_errx(1, "malformed address %s", address);
}
} else {
/*
* Either IPv6 address without brackets - and without
* a port - or IPv4 address. Just count the colons.
*/
for (ch = arg; *ch != '\0'; ch++) {
if (*ch == ':')
colons++;
}
if (colons > 1) {
addr = arg;
port = NULL;
} else {
addr = strsep(&arg, ":");
if (arg == NULL)
port = NULL;
else
port = arg;
}
}
if (port == NULL && !initiator_side)
port = "3260";
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_ADDRCONFIG | AI_NUMERICSERV;
if (initiator_side)
hints.ai_flags |= AI_PASSIVE;
error = getaddrinfo(addr, port, &hints, ai);
if (error != 0) {
fail(conn, gai_strerror(error));
log_errx(1, "getaddrinfo for %s failed: %s",
address, gai_strerror(error));
}
}
static struct connection *
connection_new(int iscsi_fd, const struct iscsi_daemon_request *request)
{
struct connection *conn;
struct iscsi_session_limits *isl;
struct addrinfo *from_ai, *to_ai;
const char *from_addr, *to_addr;
#ifdef ICL_KERNEL_PROXY
struct iscsi_daemon_connect idc;
#endif
int error, sockbuf;
conn = calloc(1, sizeof(*conn));
if (conn == NULL)
log_err(1, "calloc");
/*
* Default values, from RFC 3720, section 12.
*/
conn->conn_header_digest = CONN_DIGEST_NONE;
conn->conn_data_digest = CONN_DIGEST_NONE;
conn->conn_initial_r2t = true;
conn->conn_immediate_data = true;
conn->conn_max_recv_data_segment_length = 8192;
conn->conn_max_send_data_segment_length = 8192;
conn->conn_max_burst_length = 262144;
conn->conn_first_burst_length = 65536;
conn->conn_iscsi_fd = iscsi_fd;
conn->conn_session_id = request->idr_session_id;
memcpy(&conn->conn_conf, &request->idr_conf, sizeof(conn->conn_conf));
memcpy(&conn->conn_isid, &request->idr_isid, sizeof(conn->conn_isid));
conn->conn_tsih = request->idr_tsih;
/*
* Read the driver limits and provide reasonable defaults for the ones
* the driver doesn't care about. If a max_snd_dsl is not explicitly
* provided by the driver then we'll make sure both conn->max_snd_dsl
* and isl->max_snd_dsl are set to the rcv_dsl. This preserves historic
* behavior.
*/
isl = &conn->conn_limits;
memcpy(isl, &request->idr_limits, sizeof(*isl));
if (isl->isl_max_recv_data_segment_length == 0)
isl->isl_max_recv_data_segment_length = (1 << 24) - 1;
if (isl->isl_max_send_data_segment_length == 0)
isl->isl_max_send_data_segment_length =
isl->isl_max_recv_data_segment_length;
if (isl->isl_max_burst_length == 0)
isl->isl_max_burst_length = (1 << 24) - 1;
if (isl->isl_first_burst_length == 0)
isl->isl_first_burst_length = (1 << 24) - 1;
if (isl->isl_first_burst_length > isl->isl_max_burst_length)
isl->isl_first_burst_length = isl->isl_max_burst_length;
/*
* Limit default send length in case it won't be negotiated.
* We can't do it for other limits, since they may affect both
* sender and receiver operation, and we must obey defaults.
*/
if (conn->conn_max_send_data_segment_length >
isl->isl_max_send_data_segment_length) {
conn->conn_max_send_data_segment_length =
isl->isl_max_send_data_segment_length;
}
from_addr = conn->conn_conf.isc_initiator_addr;
to_addr = conn->conn_conf.isc_target_addr;
if (from_addr[0] != '\0')
resolve_addr(conn, from_addr, &from_ai, true);
else
from_ai = NULL;
resolve_addr(conn, to_addr, &to_ai, false);
#ifdef ICL_KERNEL_PROXY
if (conn->conn_conf.isc_iser) {
memset(&idc, 0, sizeof(idc));
idc.idc_session_id = conn->conn_session_id;
if (conn->conn_conf.isc_iser)
idc.idc_iser = 1;
idc.idc_domain = to_ai->ai_family;
idc.idc_socktype = to_ai->ai_socktype;
idc.idc_protocol = to_ai->ai_protocol;
if (from_ai != NULL) {
idc.idc_from_addr = from_ai->ai_addr;
idc.idc_from_addrlen = from_ai->ai_addrlen;
}
idc.idc_to_addr = to_ai->ai_addr;
idc.idc_to_addrlen = to_ai->ai_addrlen;
log_debugx("connecting to %s using ICL kernel proxy", to_addr);
error = ioctl(iscsi_fd, ISCSIDCONNECT, &idc);
if (error != 0) {
fail(conn, strerror(errno));
log_err(1, "failed to connect to %s "
"using ICL kernel proxy: ISCSIDCONNECT", to_addr);
}
return (conn);
}
#endif /* ICL_KERNEL_PROXY */
if (conn->conn_conf.isc_iser) {
fail(conn, "iSER not supported");
log_errx(1, "iscsid(8) compiled without ICL_KERNEL_PROXY "
"does not support iSER");
}
conn->conn_socket = socket(to_ai->ai_family, to_ai->ai_socktype,
to_ai->ai_protocol);
if (conn->conn_socket < 0) {
fail(conn, strerror(errno));
log_err(1, "failed to create socket for %s", from_addr);
}
sockbuf = SOCKBUF_SIZE;
if (setsockopt(conn->conn_socket, SOL_SOCKET, SO_RCVBUF,
&sockbuf, sizeof(sockbuf)) == -1)
log_warn("setsockopt(SO_RCVBUF) failed");
sockbuf = SOCKBUF_SIZE;
if (setsockopt(conn->conn_socket, SOL_SOCKET, SO_SNDBUF,
&sockbuf, sizeof(sockbuf)) == -1)
log_warn("setsockopt(SO_SNDBUF) failed");
if (from_ai != NULL) {
error = bind(conn->conn_socket, from_ai->ai_addr,
from_ai->ai_addrlen);
if (error != 0) {
fail(conn, strerror(errno));
log_err(1, "failed to bind to %s", from_addr);
}
}
log_debugx("connecting to %s", to_addr);
error = connect(conn->conn_socket, to_ai->ai_addr, to_ai->ai_addrlen);
if (error != 0) {
fail(conn, strerror(errno));
log_err(1, "failed to connect to %s", to_addr);
}
return (conn);
}
static void
handoff(struct connection *conn)
{
struct iscsi_daemon_handoff idh;
int error;
log_debugx("handing off connection to the kernel");
memset(&idh, 0, sizeof(idh));
idh.idh_session_id = conn->conn_session_id;
idh.idh_socket = conn->conn_socket;
strlcpy(idh.idh_target_alias, conn->conn_target_alias,
sizeof(idh.idh_target_alias));
idh.idh_tsih = conn->conn_tsih;
idh.idh_statsn = conn->conn_statsn;
idh.idh_header_digest = conn->conn_header_digest;
idh.idh_data_digest = conn->conn_data_digest;
idh.idh_initial_r2t = conn->conn_initial_r2t;
idh.idh_immediate_data = conn->conn_immediate_data;
idh.idh_max_recv_data_segment_length =
conn->conn_max_recv_data_segment_length;
idh.idh_max_send_data_segment_length =
conn->conn_max_send_data_segment_length;
idh.idh_max_burst_length = conn->conn_max_burst_length;
idh.idh_first_burst_length = conn->conn_first_burst_length;
error = ioctl(conn->conn_iscsi_fd, ISCSIDHANDOFF, &idh);
if (error != 0)
log_err(1, "ISCSIDHANDOFF");
}
void
fail(const struct connection *conn, const char *reason)
{
struct iscsi_daemon_fail idf;
int error, saved_errno;
saved_errno = errno;
memset(&idf, 0, sizeof(idf));
idf.idf_session_id = conn->conn_session_id;
strlcpy(idf.idf_reason, reason, sizeof(idf.idf_reason));
error = ioctl(conn->conn_iscsi_fd, ISCSIDFAIL, &idf);
if (error != 0)
log_err(1, "ISCSIDFAIL");
errno = saved_errno;
}
/*
* XXX: I CANT INTO LATIN
*/
static void
capsicate(struct connection *conn)
{
int error;
cap_rights_t rights;
#ifdef ICL_KERNEL_PROXY
const unsigned long cmds[] = { ISCSIDCONNECT, ISCSIDSEND, ISCSIDRECEIVE,
ISCSIDHANDOFF, ISCSIDFAIL, ISCSISADD, ISCSISREMOVE, ISCSISMODIFY };
#else
const unsigned long cmds[] = { ISCSIDHANDOFF, ISCSIDFAIL, ISCSISADD,
ISCSISREMOVE, ISCSISMODIFY };
#endif
cap_rights_init(&rights, CAP_IOCTL);
error = cap_rights_limit(conn->conn_iscsi_fd, &rights);
if (error != 0 && errno != ENOSYS)
log_err(1, "cap_rights_limit");
error = cap_ioctls_limit(conn->conn_iscsi_fd, cmds, nitems(cmds));
if (error != 0 && errno != ENOSYS)
log_err(1, "cap_ioctls_limit");
error = cap_enter();
if (error != 0 && errno != ENOSYS)
log_err(1, "cap_enter");
if (cap_sandboxed())
log_debugx("Capsicum capability mode enabled");
else
log_warnx("Capsicum capability mode not supported");
}
bool
timed_out(void)
{
return (sigalrm_received);
}
static void
sigalrm_handler(int dummy __unused)
{
/*
* It would be easiest to just log an error and exit. We can't
* do this, though, because log_errx() is not signal safe, since
* it calls syslog(3). Instead, set a flag checked by pdu_send()
* and pdu_receive(), to call log_errx() there. Should they fail
* to notice, we'll exit here one second later.
*/
if (sigalrm_received) {
/*
* Oh well. Just give up and quit.
*/
_exit(2);
}
sigalrm_received = true;
}
static void
set_timeout(int timeout)
{
struct sigaction sa;
struct itimerval itv;
int error;
if (timeout <= 0) {
log_debugx("session timeout disabled");
return;
}
bzero(&sa, sizeof(sa));
sa.sa_handler = sigalrm_handler;
sigfillset(&sa.sa_mask);
error = sigaction(SIGALRM, &sa, NULL);
if (error != 0)
log_err(1, "sigaction");
/*
* First SIGALRM will arive after conf_timeout seconds.
* If we do nothing, another one will arrive a second later.
*/
bzero(&itv, sizeof(itv));
itv.it_interval.tv_sec = 1;
itv.it_value.tv_sec = timeout;
log_debugx("setting session timeout to %d seconds",
timeout);
error = setitimer(ITIMER_REAL, &itv, NULL);
if (error != 0)
log_err(1, "setitimer");
}
static void
sigchld_handler(int dummy __unused)
{
/*
* The only purpose of this handler is to make SIGCHLD
* interrupt the ISCSIDWAIT ioctl(2), so we can call
* wait_for_children().
*/
}
static void
register_sigchld(void)
{
struct sigaction sa;
int error;
bzero(&sa, sizeof(sa));
sa.sa_handler = sigchld_handler;
sigfillset(&sa.sa_mask);
error = sigaction(SIGCHLD, &sa, NULL);
if (error != 0)
log_err(1, "sigaction");
}
static void
handle_request(int iscsi_fd, const struct iscsi_daemon_request *request, int timeout)
{
struct connection *conn;
log_set_peer_addr(request->idr_conf.isc_target_addr);
if (request->idr_conf.isc_target[0] != '\0') {
log_set_peer_name(request->idr_conf.isc_target);
setproctitle("%s (%s)", request->idr_conf.isc_target_addr, request->idr_conf.isc_target);
} else {
setproctitle("%s", request->idr_conf.isc_target_addr);
}
conn = connection_new(iscsi_fd, request);
set_timeout(timeout);
capsicate(conn);
login(conn);
if (conn->conn_conf.isc_discovery != 0)
discovery(conn);
else
handoff(conn);
log_debugx("nothing more to do; exiting");
exit (0);
}
static int
wait_for_children(bool block)
{
pid_t pid;
int status;
int num = 0;
for (;;) {
/*
* If "block" is true, wait for at least one process.
*/
if (block && num == 0)
pid = wait4(-1, &status, 0, NULL);
else
pid = wait4(-1, &status, WNOHANG, NULL);
if (pid <= 0)
break;
if (WIFSIGNALED(status)) {
log_warnx("child process %d terminated with signal %d",
pid, WTERMSIG(status));
} else if (WEXITSTATUS(status) != 0) {
log_warnx("child process %d terminated with exit status %d",
pid, WEXITSTATUS(status));
} else {
log_debugx("child process %d terminated gracefully", pid);
}
num++;
}
return (num);
}
int
main(int argc, char **argv)
{
int ch, debug = 0, error, iscsi_fd, maxproc = 30, retval, saved_errno,
timeout = 60;
bool dont_daemonize = false;
struct pidfh *pidfh;
pid_t pid, otherpid;
const char *pidfile_path = DEFAULT_PIDFILE;
struct iscsi_daemon_request request;
while ((ch = getopt(argc, argv, "P:dl:m:t:")) != -1) {
switch (ch) {
case 'P':
pidfile_path = optarg;
break;
case 'd':
dont_daemonize = true;
debug++;
break;
case 'l':
debug = atoi(optarg);
break;
case 'm':
maxproc = atoi(optarg);
break;
case 't':
timeout = atoi(optarg);
break;
case '?':
default:
usage();
}
}
argc -= optind;
if (argc != 0)
usage();
log_init(debug);
pidfh = pidfile_open(pidfile_path, 0600, &otherpid);
if (pidfh == NULL) {
if (errno == EEXIST)
log_errx(1, "daemon already running, pid: %jd.",
(intmax_t)otherpid);
log_err(1, "cannot open or create pidfile \"%s\"",
pidfile_path);
}
iscsi_fd = open(ISCSI_PATH, O_RDWR);
if (iscsi_fd < 0 && errno == ENOENT) {
saved_errno = errno;
retval = kldload("iscsi");
if (retval != -1)
iscsi_fd = open(ISCSI_PATH, O_RDWR);
else
errno = saved_errno;
}
if (iscsi_fd < 0)
log_err(1, "failed to open %s", ISCSI_PATH);
if (dont_daemonize == false) {
if (daemon(0, 0) == -1) {
log_warn("cannot daemonize");
pidfile_remove(pidfh);
exit(1);
}
}
pidfile_write(pidfh);
register_sigchld();
for (;;) {
log_debugx("waiting for request from the kernel");
memset(&request, 0, sizeof(request));
error = ioctl(iscsi_fd, ISCSIDWAIT, &request);
if (error != 0) {
if (errno == EINTR) {
nchildren -= wait_for_children(false);
assert(nchildren >= 0);
continue;
}
log_err(1, "ISCSIDWAIT");
}
if (dont_daemonize) {
log_debugx("not forking due to -d flag; "
"will exit after servicing a single request");
} else {
nchildren -= wait_for_children(false);
assert(nchildren >= 0);
while (maxproc > 0 && nchildren >= maxproc) {
log_debugx("maxproc limit of %d child processes hit; "
"waiting for child process to exit", maxproc);
nchildren -= wait_for_children(true);
assert(nchildren >= 0);
}
log_debugx("incoming connection; forking child process #%d",
nchildren);
nchildren++;
pid = fork();
if (pid < 0)
log_err(1, "fork");
if (pid > 0)
continue;
}
pidfile_close(pidfh);
handle_request(iscsi_fd, &request, timeout);
}
return (0);
}