diff options
Diffstat (limited to 'usr.sbin/iscsid/iscsid.c')
-rw-r--r-- | usr.sbin/iscsid/iscsid.c | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/usr.sbin/iscsid/iscsid.c b/usr.sbin/iscsid/iscsid.c new file mode 100644 index 0000000..7943eb1 --- /dev/null +++ b/usr.sbin/iscsid/iscsid.c @@ -0,0 +1,576 @@ +/*- + * 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. + * + * $FreeBSD$ + */ + +#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/capability.h> +#include <sys/wait.h> +#include <assert.h> +#include <errno.h> +#include <fcntl.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 <libutil.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 int +resolve_addr(const char *address, struct addrinfo **ai) +{ + struct addrinfo hints; + char *arg, *addr, *ch; + const char *port; + int error, colons = 0; + + arg = checked_strdup(address); + + if (arg[0] == '\0') { + log_warnx("empty address"); + return (1); + } + if (arg[0] == '[') { + /* + * IPv6 address in square brackets, perhaps with port. + */ + arg++; + addr = strsep(&arg, "]"); + if (arg == NULL) { + log_warnx("invalid address %s", address); + return (1); + } + if (arg[0] == '\0') { + port = "3260"; + } else if (arg[0] == ':') { + port = arg + 1; + } else { + log_warnx("invalid address %s", address); + return (1); + } + } 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 = "3260"; + } else { + addr = strsep(&arg, ":"); + if (arg == NULL) + port = "3260"; + else + port = arg; + } + } + + memset(&hints, 0, sizeof(hints)); + hints.ai_family = PF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + hints.ai_flags = AI_PASSIVE; + + error = getaddrinfo(addr, port, &hints, ai); + if (error != 0) { + log_warnx("getaddrinfo for %s failed: %s", + address, gai_strerror(error)); + return (1); + } + + return (0); +} + +static struct connection * +connection_new(unsigned int session_id, const struct iscsi_session_conf *conf, + int iscsi_fd) +{ + struct connection *conn; + struct addrinfo *from_ai, *to_ai; + const char *from_addr, *to_addr; +#ifdef ICL_KERNEL_PROXY + struct iscsi_daemon_connect *idc; +#endif + int error; + + 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_data_segment_length = 8192; + conn->conn_max_burst_length = 262144; + conn->conn_first_burst_length = 65536; + + conn->conn_session_id = session_id; + /* + * XXX: Should we sanitize this somehow? + */ + memcpy(&conn->conn_conf, conf, sizeof(conn->conn_conf)); + + from_addr = conn->conn_conf.isc_initiator_addr; + to_addr = conn->conn_conf.isc_target_addr; + + if (from_addr[0] != '\0') { + error = resolve_addr(from_addr, &from_ai); + if (error != 0) + log_errx(1, "failed to resolve initiator address %s", + from_addr); + } else { + from_ai = NULL; + } + + error = resolve_addr(to_addr, &to_ai); + if (error != 0) + log_errx(1, "failed to resolve target address %s", to_addr); + + conn->conn_iscsi_fd = iscsi_fd; + +#ifdef ICL_KERNEL_PROXY + + idc = calloc(1, sizeof(*idc)); + if (idc == NULL) + log_err(1, "calloc"); + + 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", + to_addr); + } + +#else /* !ICL_KERNEL_PROXY */ + + if (conn->conn_conf.isc_iser) + 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) + log_err(1, "failed to create socket for %s", from_addr); + if (from_ai != NULL) { + error = bind(conn->conn_socket, from_ai->ai_addr, + from_ai->ai_addrlen); + if (error != 0) + 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); + } + +#endif /* !ICL_KERNEL_PROXY */ + + return (conn); +} + +static void +handoff(struct connection *conn) +{ + struct iscsi_daemon_handoff *idh; + int error; + + log_debugx("handing off connection to the kernel"); + + idh = calloc(1, sizeof(*idh)); + if (idh == NULL) + log_err(1, "calloc"); + idh->idh_session_id = conn->conn_session_id; +#ifndef ICL_KERNEL_PROXY + idh->idh_socket = conn->conn_socket; +#endif + strlcpy(idh->idh_target_alias, conn->conn_target_alias, + sizeof(idh->idh_target_alias)); + memcpy(idh->idh_isid, conn->conn_isid, sizeof(idh->idh_isid)); + 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_data_segment_length = conn->conn_max_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; + + idf = calloc(1, sizeof(*idf)); + if (idf == NULL) + log_err(1, "calloc"); + + 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"); +} + +/* + * 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 }; +#else + const unsigned long cmds[] = { ISCSIDHANDOFF, ISCSIDFAIL, ISCSISADD, + ISCSISREMOVE }; +#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, + sizeof(cmds) / sizeof(cmds[0])); + 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 +handle_request(int iscsi_fd, 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(request->idr_session_id, &request->idr_conf, iscsi_fd); + 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) { + 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); + + for (;;) { + log_debugx("waiting for request from the kernel"); + + request = calloc(1, sizeof(*request)); + if (request == NULL) + log_err(1, "calloc"); + + 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); +} |