Merge remote-tracking branch 'remotes/cohuck-gitlab/tags/s390x-20210409' into staging
[qemu/ar7.git] / scsi / qemu-pr-helper.c
blob7b9389b47b5ad374de17728e64a120c9d1ef1221
1 /*
2 * Privileged helper to handle persistent reservation commands for QEMU
4 * Copyright (C) 2017 Red Hat, Inc. <pbonzini@redhat.com>
6 * Author: Paolo Bonzini <pbonzini@redhat.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; under version 2 of the License.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "qemu/osdep.h"
22 #include <getopt.h>
23 #include <sys/ioctl.h>
24 #include <linux/dm-ioctl.h>
25 #include <scsi/sg.h>
27 #ifdef CONFIG_LIBCAP_NG
28 #include <cap-ng.h>
29 #endif
30 #include <pwd.h>
31 #include <grp.h>
33 #ifdef CONFIG_MPATH
34 #include <libudev.h>
35 #include <mpath_cmd.h>
36 #include <mpath_persist.h>
37 #endif
39 #include "qemu-common.h"
40 #include "qapi/error.h"
41 #include "qemu/cutils.h"
42 #include "qemu/main-loop.h"
43 #include "qemu/module.h"
44 #include "qemu/error-report.h"
45 #include "qemu/config-file.h"
46 #include "qemu/bswap.h"
47 #include "qemu/log.h"
48 #include "qemu/systemd.h"
49 #include "qapi/util.h"
50 #include "qapi/qmp/qstring.h"
51 #include "io/channel-socket.h"
52 #include "trace/control.h"
53 #include "qemu-version.h"
55 #include "block/aio.h"
56 #include "block/thread-pool.h"
58 #include "scsi/constants.h"
59 #include "scsi/utils.h"
60 #include "pr-helper.h"
62 #define PR_OUT_FIXED_PARAM_SIZE 24
64 static char *socket_path;
65 static char *pidfile;
66 static enum { RUNNING, TERMINATE, TERMINATING } state;
67 static QIOChannelSocket *server_ioc;
68 static int server_watch;
69 static int num_active_sockets = 1;
70 static int noisy;
71 static int verbose;
73 #ifdef CONFIG_LIBCAP_NG
74 static int uid = -1;
75 static int gid = -1;
76 #endif
78 static void compute_default_paths(void)
80 socket_path = qemu_get_local_state_pathname("run/qemu-pr-helper.sock");
81 pidfile = qemu_get_local_state_pathname("run/qemu-pr-helper.pid");
84 static void usage(const char *name)
86 (printf) (
87 "Usage: %s [OPTIONS] FILE\n"
88 "Persistent Reservation helper program for QEMU\n"
89 "\n"
90 " -h, --help display this help and exit\n"
91 " -V, --version output version information and exit\n"
92 "\n"
93 " -d, --daemon run in the background\n"
94 " -f, --pidfile=PATH PID file when running as a daemon\n"
95 " (default '%s')\n"
96 " -k, --socket=PATH path to the unix socket\n"
97 " (default '%s')\n"
98 " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
99 " specify tracing options\n"
100 #ifdef CONFIG_LIBCAP_NG
101 " -u, --user=USER user to drop privileges to\n"
102 " -g, --group=GROUP group to drop privileges to\n"
103 #endif
104 "\n"
105 QEMU_HELP_BOTTOM "\n"
106 , name, pidfile, socket_path);
109 static void version(const char *name)
111 printf(
112 "%s " QEMU_FULL_VERSION "\n"
113 "Written by Paolo Bonzini.\n"
114 "\n"
115 QEMU_COPYRIGHT "\n"
116 "This is free software; see the source for copying conditions. There is NO\n"
117 "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
118 , name);
121 /* SG_IO support */
123 typedef struct PRHelperSGIOData {
124 int fd;
125 const uint8_t *cdb;
126 uint8_t *sense;
127 uint8_t *buf;
128 int sz; /* input/output */
129 int dir;
130 } PRHelperSGIOData;
132 static int do_sgio_worker(void *opaque)
134 PRHelperSGIOData *data = opaque;
135 struct sg_io_hdr io_hdr;
136 int ret;
137 int status;
138 SCSISense sense_code;
140 memset(data->sense, 0, PR_HELPER_SENSE_SIZE);
141 memset(&io_hdr, 0, sizeof(io_hdr));
142 io_hdr.interface_id = 'S';
143 io_hdr.cmd_len = PR_HELPER_CDB_SIZE;
144 io_hdr.cmdp = (uint8_t *)data->cdb;
145 io_hdr.sbp = data->sense;
146 io_hdr.mx_sb_len = PR_HELPER_SENSE_SIZE;
147 io_hdr.timeout = 1;
148 io_hdr.dxfer_direction = data->dir;
149 io_hdr.dxferp = (char *)data->buf;
150 io_hdr.dxfer_len = data->sz;
151 ret = ioctl(data->fd, SG_IO, &io_hdr);
153 if (ret < 0) {
154 status = scsi_sense_from_errno(errno, &sense_code);
155 if (status == CHECK_CONDITION) {
156 scsi_build_sense(data->sense, sense_code);
158 } else if (io_hdr.host_status != SCSI_HOST_OK) {
159 status = scsi_sense_from_host_status(io_hdr.host_status, &sense_code);
160 if (status == CHECK_CONDITION) {
161 scsi_build_sense(data->sense, sense_code);
163 } else if (io_hdr.driver_status & SG_ERR_DRIVER_TIMEOUT) {
164 status = BUSY;
165 } else {
166 status = io_hdr.status;
169 if (status == GOOD) {
170 data->sz -= io_hdr.resid;
171 } else {
172 data->sz = 0;
175 return status;
178 static int do_sgio(int fd, const uint8_t *cdb, uint8_t *sense,
179 uint8_t *buf, int *sz, int dir)
181 ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context());
182 int r;
184 PRHelperSGIOData data = {
185 .fd = fd,
186 .cdb = cdb,
187 .sense = sense,
188 .buf = buf,
189 .sz = *sz,
190 .dir = dir,
193 r = thread_pool_submit_co(pool, do_sgio_worker, &data);
194 *sz = data.sz;
195 return r;
198 /* Device mapper interface */
200 #ifdef CONFIG_MPATH
201 #define CONTROL_PATH "/dev/mapper/control"
203 typedef struct DMData {
204 struct dm_ioctl dm;
205 uint8_t data[1024];
206 } DMData;
208 static int control_fd;
210 static void *dm_ioctl(int ioc, struct dm_ioctl *dm)
212 static DMData d;
213 memcpy(&d.dm, dm, sizeof(d.dm));
214 QEMU_BUILD_BUG_ON(sizeof(d.data) < sizeof(struct dm_target_spec));
216 d.dm.version[0] = DM_VERSION_MAJOR;
217 d.dm.version[1] = 0;
218 d.dm.version[2] = 0;
219 d.dm.data_size = 1024;
220 d.dm.data_start = offsetof(DMData, data);
221 if (ioctl(control_fd, ioc, &d) < 0) {
222 return NULL;
224 memcpy(dm, &d.dm, sizeof(d.dm));
225 return &d.data;
228 static void *dm_dev_ioctl(int fd, int ioc, struct dm_ioctl *dm)
230 struct stat st;
231 int r;
233 r = fstat(fd, &st);
234 if (r < 0) {
235 perror("fstat");
236 exit(1);
239 dm->dev = st.st_rdev;
240 return dm_ioctl(ioc, dm);
243 static void dm_init(void)
245 control_fd = open(CONTROL_PATH, O_RDWR);
246 if (control_fd < 0) {
247 perror("Cannot open " CONTROL_PATH);
248 exit(1);
250 struct dm_ioctl dm = { };
251 if (!dm_ioctl(DM_VERSION, &dm)) {
252 perror("ioctl");
253 exit(1);
255 if (dm.version[0] != DM_VERSION_MAJOR) {
256 fprintf(stderr, "Unsupported device mapper interface");
257 exit(1);
261 /* Variables required by libmultipath and libmpathpersist. */
262 QEMU_BUILD_BUG_ON(PR_HELPER_DATA_SIZE > MPATH_MAX_PARAM_LEN);
263 static struct config *multipath_conf;
264 unsigned mpath_mx_alloc_len = PR_HELPER_DATA_SIZE;
265 int logsink;
266 struct udev *udev;
268 extern struct config *get_multipath_config(void);
269 struct config *get_multipath_config(void)
271 return multipath_conf;
274 extern void put_multipath_config(struct config *conf);
275 void put_multipath_config(struct config *conf)
279 static void multipath_pr_init(void)
281 udev = udev_new();
282 #ifdef CONFIG_MPATH_NEW_API
283 multipath_conf = mpath_lib_init();
284 #else
285 mpath_lib_init(udev);
286 #endif
289 static int is_mpath(int fd)
291 struct dm_ioctl dm = { .flags = DM_NOFLUSH_FLAG };
292 struct dm_target_spec *tgt;
294 tgt = dm_dev_ioctl(fd, DM_TABLE_STATUS, &dm);
295 if (!tgt) {
296 if (errno == ENXIO) {
297 return 0;
299 perror("ioctl");
300 exit(EXIT_FAILURE);
302 return !strncmp(tgt->target_type, "multipath", DM_MAX_TYPE_NAME);
305 static SCSISense mpath_generic_sense(int r)
307 switch (r) {
308 case MPATH_PR_SENSE_NOT_READY:
309 return SENSE_CODE(NOT_READY);
310 case MPATH_PR_SENSE_MEDIUM_ERROR:
311 return SENSE_CODE(READ_ERROR);
312 case MPATH_PR_SENSE_HARDWARE_ERROR:
313 return SENSE_CODE(TARGET_FAILURE);
314 case MPATH_PR_SENSE_ABORTED_COMMAND:
315 return SENSE_CODE(IO_ERROR);
316 default:
317 abort();
321 static int mpath_reconstruct_sense(int fd, int r, uint8_t *sense)
323 switch (r) {
324 case MPATH_PR_SUCCESS:
325 return GOOD;
326 case MPATH_PR_SENSE_NOT_READY:
327 case MPATH_PR_SENSE_MEDIUM_ERROR:
328 case MPATH_PR_SENSE_HARDWARE_ERROR:
329 case MPATH_PR_SENSE_ABORTED_COMMAND:
331 /* libmpathpersist ate the exact sense. Try to find it by
332 * issuing TEST UNIT READY.
334 uint8_t cdb[6] = { TEST_UNIT_READY };
335 int sz = 0;
336 int ret = do_sgio(fd, cdb, sense, NULL, &sz, SG_DXFER_NONE);
338 if (ret != GOOD) {
339 return ret;
341 scsi_build_sense(sense, mpath_generic_sense(r));
342 return CHECK_CONDITION;
345 case MPATH_PR_SENSE_UNIT_ATTENTION:
346 /* Congratulations libmpathpersist, you ruined the Unit Attention...
347 * Return a heavyweight one.
349 scsi_build_sense(sense, SENSE_CODE(SCSI_BUS_RESET));
350 return CHECK_CONDITION;
351 case MPATH_PR_SENSE_INVALID_OP:
352 /* Only one valid sense. */
353 scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE));
354 return CHECK_CONDITION;
355 case MPATH_PR_ILLEGAL_REQ:
356 /* Guess. */
357 scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM));
358 return CHECK_CONDITION;
359 case MPATH_PR_NO_SENSE:
360 scsi_build_sense(sense, SENSE_CODE(NO_SENSE));
361 return CHECK_CONDITION;
363 case MPATH_PR_RESERV_CONFLICT:
364 return RESERVATION_CONFLICT;
366 case MPATH_PR_OTHER:
367 default:
368 scsi_build_sense(sense, SENSE_CODE(LUN_COMM_FAILURE));
369 return CHECK_CONDITION;
373 static int multipath_pr_in(int fd, const uint8_t *cdb, uint8_t *sense,
374 uint8_t *data, int sz)
376 int rq_servact = cdb[1];
377 struct prin_resp resp;
378 size_t written;
379 int r;
381 switch (rq_servact) {
382 case MPATH_PRIN_RKEY_SA:
383 case MPATH_PRIN_RRES_SA:
384 case MPATH_PRIN_RCAP_SA:
385 break;
386 case MPATH_PRIN_RFSTAT_SA:
387 /* Nobody implements it anyway, so bail out. */
388 default:
389 /* Cannot parse any other output. */
390 scsi_build_sense(sense, SENSE_CODE(INVALID_FIELD));
391 return CHECK_CONDITION;
394 r = mpath_persistent_reserve_in(fd, rq_servact, &resp, noisy, verbose);
395 if (r == MPATH_PR_SUCCESS) {
396 switch (rq_servact) {
397 case MPATH_PRIN_RKEY_SA:
398 case MPATH_PRIN_RRES_SA: {
399 struct prin_readdescr *out = &resp.prin_descriptor.prin_readkeys;
400 assert(sz >= 8);
401 written = MIN(out->additional_length + 8, sz);
402 stl_be_p(&data[0], out->prgeneration);
403 stl_be_p(&data[4], out->additional_length);
404 memcpy(&data[8], out->key_list, written - 8);
405 break;
407 case MPATH_PRIN_RCAP_SA: {
408 struct prin_capdescr *out = &resp.prin_descriptor.prin_readcap;
409 assert(sz >= 6);
410 written = 6;
411 stw_be_p(&data[0], out->length);
412 data[2] = out->flags[0];
413 data[3] = out->flags[1];
414 stw_be_p(&data[4], out->pr_type_mask);
415 break;
417 default:
418 scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE));
419 return CHECK_CONDITION;
421 assert(written <= sz);
422 memset(data + written, 0, sz - written);
425 return mpath_reconstruct_sense(fd, r, sense);
428 static int multipath_pr_out(int fd, const uint8_t *cdb, uint8_t *sense,
429 const uint8_t *param, int sz)
431 int rq_servact = cdb[1];
432 int rq_scope = cdb[2] >> 4;
433 int rq_type = cdb[2] & 0xf;
434 g_autofree struct prout_param_descriptor *paramp = NULL;
435 char transportids[PR_HELPER_DATA_SIZE];
436 int r;
438 paramp = g_malloc0(sizeof(struct prout_param_descriptor)
439 + sizeof(struct transportid *) * MPATH_MX_TIDS);
441 if (sz < PR_OUT_FIXED_PARAM_SIZE) {
442 /* Illegal request, Parameter list length error. This isn't fatal;
443 * we have read the data, send an error without closing the socket.
445 scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM_LEN));
446 return CHECK_CONDITION;
449 switch (rq_servact) {
450 case MPATH_PROUT_REG_SA:
451 case MPATH_PROUT_RES_SA:
452 case MPATH_PROUT_REL_SA:
453 case MPATH_PROUT_CLEAR_SA:
454 case MPATH_PROUT_PREE_SA:
455 case MPATH_PROUT_PREE_AB_SA:
456 case MPATH_PROUT_REG_IGN_SA:
457 break;
458 case MPATH_PROUT_REG_MOV_SA:
459 /* Not supported by struct prout_param_descriptor. */
460 default:
461 /* Cannot parse any other input. */
462 scsi_build_sense(sense, SENSE_CODE(INVALID_FIELD));
463 return CHECK_CONDITION;
466 /* Convert input data, especially transport IDs, to the structs
467 * used by libmpathpersist (which, of course, will immediately
468 * do the opposite).
470 memcpy(&paramp->key, &param[0], 8);
471 memcpy(&paramp->sa_key, &param[8], 8);
472 paramp->sa_flags = param[20];
473 if (sz > PR_OUT_FIXED_PARAM_SIZE) {
474 size_t transportid_len;
475 int i, j;
476 if (sz < PR_OUT_FIXED_PARAM_SIZE + 4) {
477 scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM_LEN));
478 return CHECK_CONDITION;
480 transportid_len = ldl_be_p(&param[24]) + PR_OUT_FIXED_PARAM_SIZE + 4;
481 if (transportid_len > sz) {
482 scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM));
483 return CHECK_CONDITION;
485 for (i = PR_OUT_FIXED_PARAM_SIZE + 4, j = 0; i < transportid_len; ) {
486 struct transportid *id = (struct transportid *) &transportids[j];
487 int len;
489 id->format_code = param[i] & 0xc0;
490 id->protocol_id = param[i] & 0x0f;
491 switch (param[i] & 0xcf) {
492 case 0:
493 /* FC transport. */
494 if (i + 24 > transportid_len) {
495 goto illegal_req;
497 memcpy(id->n_port_name, &param[i + 8], 8);
498 j += offsetof(struct transportid, n_port_name[8]);
499 i += 24;
500 break;
501 case 5:
502 case 0x45:
503 /* iSCSI transport. */
504 len = lduw_be_p(&param[i + 2]);
505 if (len > 252 || (len & 3) || i + len + 4 > transportid_len) {
506 /* For format code 00, the standard says the maximum is 223
507 * plus the NUL terminator. For format code 01 there is no
508 * maximum length, but libmpathpersist ignores the first
509 * byte of id->iscsi_name so our maximum is 252.
511 goto illegal_req;
513 if (memchr(&param[i + 4], 0, len) == NULL) {
514 goto illegal_req;
516 memcpy(id->iscsi_name, &param[i + 2], len + 2);
517 j += offsetof(struct transportid, iscsi_name[len + 2]);
518 i += len + 4;
519 break;
520 case 6:
521 /* SAS transport. */
522 if (i + 24 > transportid_len) {
523 goto illegal_req;
525 memcpy(id->sas_address, &param[i + 4], 8);
526 j += offsetof(struct transportid, sas_address[8]);
527 i += 24;
528 break;
529 default:
530 illegal_req:
531 scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM));
532 return CHECK_CONDITION;
535 assert(paramp->num_transportid < MPATH_MX_TIDS);
536 paramp->trnptid_list[paramp->num_transportid++] = id;
540 r = mpath_persistent_reserve_out(fd, rq_servact, rq_scope, rq_type,
541 paramp, noisy, verbose);
542 return mpath_reconstruct_sense(fd, r, sense);
544 #endif
546 static int do_pr_in(int fd, const uint8_t *cdb, uint8_t *sense,
547 uint8_t *data, int *resp_sz)
549 #ifdef CONFIG_MPATH
550 if (is_mpath(fd)) {
551 /* multipath_pr_in fills the whole input buffer. */
552 int r = multipath_pr_in(fd, cdb, sense, data, *resp_sz);
553 if (r != GOOD) {
554 *resp_sz = 0;
556 return r;
558 #endif
560 return do_sgio(fd, cdb, sense, data, resp_sz,
561 SG_DXFER_FROM_DEV);
564 static int do_pr_out(int fd, const uint8_t *cdb, uint8_t *sense,
565 const uint8_t *param, int sz)
567 int resp_sz;
569 if ((fcntl(fd, F_GETFL) & O_ACCMODE) == O_RDONLY) {
570 scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE));
571 return CHECK_CONDITION;
574 #ifdef CONFIG_MPATH
575 if (is_mpath(fd)) {
576 return multipath_pr_out(fd, cdb, sense, param, sz);
578 #endif
580 resp_sz = sz;
581 return do_sgio(fd, cdb, sense, (uint8_t *)param, &resp_sz,
582 SG_DXFER_TO_DEV);
585 /* Client */
587 typedef struct PRHelperClient {
588 QIOChannelSocket *ioc;
589 Coroutine *co;
590 int fd;
591 uint8_t data[PR_HELPER_DATA_SIZE];
592 } PRHelperClient;
594 typedef struct PRHelperRequest {
595 int fd;
596 size_t sz;
597 uint8_t cdb[PR_HELPER_CDB_SIZE];
598 } PRHelperRequest;
600 static int coroutine_fn prh_read(PRHelperClient *client, void *buf, int sz,
601 Error **errp)
603 int ret = 0;
605 while (sz > 0) {
606 int *fds = NULL;
607 size_t nfds = 0;
608 int i;
609 struct iovec iov;
610 ssize_t n_read;
612 iov.iov_base = buf;
613 iov.iov_len = sz;
614 n_read = qio_channel_readv_full(QIO_CHANNEL(client->ioc), &iov, 1,
615 &fds, &nfds, errp);
617 if (n_read == QIO_CHANNEL_ERR_BLOCK) {
618 qio_channel_yield(QIO_CHANNEL(client->ioc), G_IO_IN);
619 continue;
621 if (n_read <= 0) {
622 ret = n_read ? n_read : -1;
623 goto err;
626 /* Stash one file descriptor per request. */
627 if (nfds) {
628 bool too_many = false;
629 for (i = 0; i < nfds; i++) {
630 if (client->fd == -1) {
631 client->fd = fds[i];
632 } else {
633 close(fds[i]);
634 too_many = true;
637 g_free(fds);
638 if (too_many) {
639 ret = -1;
640 goto err;
644 buf += n_read;
645 sz -= n_read;
648 return 0;
650 err:
651 if (client->fd != -1) {
652 close(client->fd);
653 client->fd = -1;
655 return ret;
658 static int coroutine_fn prh_read_request(PRHelperClient *client,
659 PRHelperRequest *req,
660 PRHelperResponse *resp, Error **errp)
662 uint32_t sz;
664 if (prh_read(client, req->cdb, sizeof(req->cdb), NULL) < 0) {
665 return -1;
668 if (client->fd == -1) {
669 error_setg(errp, "No file descriptor in request.");
670 return -1;
673 if (req->cdb[0] != PERSISTENT_RESERVE_OUT &&
674 req->cdb[0] != PERSISTENT_RESERVE_IN) {
675 error_setg(errp, "Invalid CDB, closing socket.");
676 goto out_close;
679 sz = scsi_cdb_xfer(req->cdb);
680 if (sz > sizeof(client->data)) {
681 goto out_close;
684 if (req->cdb[0] == PERSISTENT_RESERVE_OUT) {
685 if (qio_channel_read_all(QIO_CHANNEL(client->ioc),
686 (char *)client->data, sz,
687 errp) < 0) {
688 goto out_close;
692 req->fd = client->fd;
693 req->sz = sz;
694 client->fd = -1;
695 return sz;
697 out_close:
698 close(client->fd);
699 client->fd = -1;
700 return -1;
703 static int coroutine_fn prh_write_response(PRHelperClient *client,
704 PRHelperRequest *req,
705 PRHelperResponse *resp, Error **errp)
707 ssize_t r;
708 size_t sz;
710 if (req->cdb[0] == PERSISTENT_RESERVE_IN && resp->result == GOOD) {
711 assert(resp->sz <= req->sz && resp->sz <= sizeof(client->data));
712 } else {
713 assert(resp->sz == 0);
716 sz = resp->sz;
718 resp->result = cpu_to_be32(resp->result);
719 resp->sz = cpu_to_be32(resp->sz);
720 r = qio_channel_write_all(QIO_CHANNEL(client->ioc),
721 (char *) resp, sizeof(*resp), errp);
722 if (r < 0) {
723 return r;
726 r = qio_channel_write_all(QIO_CHANNEL(client->ioc),
727 (char *) client->data,
728 sz, errp);
729 return r < 0 ? r : 0;
732 static void coroutine_fn prh_co_entry(void *opaque)
734 PRHelperClient *client = opaque;
735 Error *local_err = NULL;
736 uint32_t flags;
737 int r;
739 qio_channel_set_blocking(QIO_CHANNEL(client->ioc),
740 false, NULL);
741 qio_channel_attach_aio_context(QIO_CHANNEL(client->ioc),
742 qemu_get_aio_context());
744 /* A very simple negotiation for future extensibility. No features
745 * are defined so write 0.
747 flags = cpu_to_be32(0);
748 r = qio_channel_write_all(QIO_CHANNEL(client->ioc),
749 (char *) &flags, sizeof(flags), NULL);
750 if (r < 0) {
751 goto out;
754 r = qio_channel_read_all(QIO_CHANNEL(client->ioc),
755 (char *) &flags, sizeof(flags), NULL);
756 if (be32_to_cpu(flags) != 0 || r < 0) {
757 goto out;
760 while (qatomic_read(&state) == RUNNING) {
761 PRHelperRequest req;
762 PRHelperResponse resp;
763 int sz;
765 sz = prh_read_request(client, &req, &resp, &local_err);
766 if (sz < 0) {
767 break;
770 num_active_sockets++;
771 if (req.cdb[0] == PERSISTENT_RESERVE_OUT) {
772 r = do_pr_out(req.fd, req.cdb, resp.sense,
773 client->data, sz);
774 resp.sz = 0;
775 } else {
776 resp.sz = sizeof(client->data);
777 r = do_pr_in(req.fd, req.cdb, resp.sense,
778 client->data, &resp.sz);
779 resp.sz = MIN(resp.sz, sz);
781 num_active_sockets--;
782 close(req.fd);
783 if (r == -1) {
784 break;
786 resp.result = r;
788 if (prh_write_response(client, &req, &resp, &local_err) < 0) {
789 break;
793 if (local_err) {
794 if (verbose == 0) {
795 error_free(local_err);
796 } else {
797 error_report_err(local_err);
801 out:
802 qio_channel_detach_aio_context(QIO_CHANNEL(client->ioc));
803 object_unref(OBJECT(client->ioc));
804 g_free(client);
807 static gboolean accept_client(QIOChannel *ioc, GIOCondition cond, gpointer opaque)
809 QIOChannelSocket *cioc;
810 PRHelperClient *prh;
812 cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc),
813 NULL);
814 if (!cioc) {
815 return TRUE;
818 prh = g_new(PRHelperClient, 1);
819 prh->ioc = cioc;
820 prh->fd = -1;
821 prh->co = qemu_coroutine_create(prh_co_entry, prh);
822 qemu_coroutine_enter(prh->co);
824 return TRUE;
827 static void termsig_handler(int signum)
829 qatomic_cmpxchg(&state, RUNNING, TERMINATE);
830 qemu_notify_event();
833 static void close_server_socket(void)
835 assert(server_ioc);
837 g_source_remove(server_watch);
838 server_watch = -1;
839 object_unref(OBJECT(server_ioc));
840 num_active_sockets--;
843 #ifdef CONFIG_LIBCAP_NG
844 static int drop_privileges(void)
846 /* clear all capabilities */
847 capng_clear(CAPNG_SELECT_BOTH);
849 if (capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED,
850 CAP_SYS_RAWIO) < 0) {
851 return -1;
854 #ifdef CONFIG_MPATH
855 /* For /dev/mapper/control ioctls */
856 if (capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED,
857 CAP_SYS_ADMIN) < 0) {
858 return -1;
860 #endif
862 /* Change user/group id, retaining the capabilities. Because file descriptors
863 * are passed via SCM_RIGHTS, we don't need supplementary groups (and in
864 * fact the helper can run as "nobody").
866 if (capng_change_id(uid != -1 ? uid : getuid(),
867 gid != -1 ? gid : getgid(),
868 CAPNG_DROP_SUPP_GRP | CAPNG_CLEAR_BOUNDING)) {
869 return -1;
872 return 0;
874 #endif
876 int main(int argc, char **argv)
878 const char *sopt = "hVk:f:dT:u:g:vq";
879 struct option lopt[] = {
880 { "help", no_argument, NULL, 'h' },
881 { "version", no_argument, NULL, 'V' },
882 { "socket", required_argument, NULL, 'k' },
883 { "pidfile", required_argument, NULL, 'f' },
884 { "daemon", no_argument, NULL, 'd' },
885 { "trace", required_argument, NULL, 'T' },
886 { "user", required_argument, NULL, 'u' },
887 { "group", required_argument, NULL, 'g' },
888 { "verbose", no_argument, NULL, 'v' },
889 { "quiet", no_argument, NULL, 'q' },
890 { NULL, 0, NULL, 0 }
892 int opt_ind = 0;
893 int loglevel = 1;
894 int quiet = 0;
895 int ch;
896 Error *local_err = NULL;
897 bool daemonize = false;
898 bool pidfile_specified = false;
899 bool socket_path_specified = false;
900 unsigned socket_activation;
902 struct sigaction sa_sigterm;
903 memset(&sa_sigterm, 0, sizeof(sa_sigterm));
904 sa_sigterm.sa_handler = termsig_handler;
905 sigaction(SIGTERM, &sa_sigterm, NULL);
906 sigaction(SIGINT, &sa_sigterm, NULL);
907 sigaction(SIGHUP, &sa_sigterm, NULL);
909 signal(SIGPIPE, SIG_IGN);
911 error_init(argv[0]);
912 module_call_init(MODULE_INIT_TRACE);
913 module_call_init(MODULE_INIT_QOM);
914 qemu_add_opts(&qemu_trace_opts);
915 qemu_init_exec_dir(argv[0]);
917 compute_default_paths();
919 while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
920 switch (ch) {
921 case 'k':
922 g_free(socket_path);
923 socket_path = g_strdup(optarg);
924 socket_path_specified = true;
925 if (socket_path[0] != '/') {
926 error_report("socket path must be absolute");
927 exit(EXIT_FAILURE);
929 break;
930 case 'f':
931 g_free(pidfile);
932 pidfile = g_strdup(optarg);
933 pidfile_specified = true;
934 break;
935 #ifdef CONFIG_LIBCAP_NG
936 case 'u': {
937 unsigned long res;
938 struct passwd *userinfo = getpwnam(optarg);
939 if (userinfo) {
940 uid = userinfo->pw_uid;
941 } else if (qemu_strtoul(optarg, NULL, 10, &res) == 0 &&
942 (uid_t)res == res) {
943 uid = res;
944 } else {
945 error_report("invalid user '%s'", optarg);
946 exit(EXIT_FAILURE);
948 break;
950 case 'g': {
951 unsigned long res;
952 struct group *groupinfo = getgrnam(optarg);
953 if (groupinfo) {
954 gid = groupinfo->gr_gid;
955 } else if (qemu_strtoul(optarg, NULL, 10, &res) == 0 &&
956 (gid_t)res == res) {
957 gid = res;
958 } else {
959 error_report("invalid group '%s'", optarg);
960 exit(EXIT_FAILURE);
962 break;
964 #else
965 case 'u':
966 case 'g':
967 error_report("-%c not supported by this %s", ch, argv[0]);
968 exit(1);
969 #endif
970 case 'd':
971 daemonize = true;
972 break;
973 case 'q':
974 quiet = 1;
975 break;
976 case 'v':
977 ++loglevel;
978 break;
979 case 'T':
980 trace_opt_parse(optarg);
981 break;
982 case 'V':
983 version(argv[0]);
984 exit(EXIT_SUCCESS);
985 break;
986 case 'h':
987 usage(argv[0]);
988 exit(EXIT_SUCCESS);
989 break;
990 case '?':
991 error_report("Try `%s --help' for more information.", argv[0]);
992 exit(EXIT_FAILURE);
996 /* set verbosity */
997 noisy = !quiet && (loglevel >= 3);
998 verbose = quiet ? 0 : MIN(loglevel, 3);
1000 if (!trace_init_backends()) {
1001 exit(EXIT_FAILURE);
1003 trace_init_file();
1004 qemu_set_log(LOG_TRACE);
1006 #ifdef CONFIG_MPATH
1007 dm_init();
1008 multipath_pr_init();
1009 #endif
1011 socket_activation = check_socket_activation();
1012 if (socket_activation == 0) {
1013 SocketAddress saddr;
1014 saddr = (SocketAddress){
1015 .type = SOCKET_ADDRESS_TYPE_UNIX,
1016 .u.q_unix.path = socket_path,
1018 server_ioc = qio_channel_socket_new();
1019 if (qio_channel_socket_listen_sync(server_ioc, &saddr,
1020 1, &local_err) < 0) {
1021 object_unref(OBJECT(server_ioc));
1022 error_report_err(local_err);
1023 return 1;
1025 } else {
1026 /* Using socket activation - check user didn't use -p etc. */
1027 if (socket_path_specified) {
1028 error_report("Unix socket can't be set when using socket activation");
1029 exit(EXIT_FAILURE);
1032 /* Can only listen on a single socket. */
1033 if (socket_activation > 1) {
1034 error_report("%s does not support socket activation with LISTEN_FDS > 1",
1035 argv[0]);
1036 exit(EXIT_FAILURE);
1038 server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD,
1039 &local_err);
1040 if (server_ioc == NULL) {
1041 error_reportf_err(local_err,
1042 "Failed to use socket activation: ");
1043 exit(EXIT_FAILURE);
1047 if (qemu_init_main_loop(&local_err)) {
1048 error_report_err(local_err);
1049 exit(EXIT_FAILURE);
1052 server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc),
1053 G_IO_IN,
1054 accept_client,
1055 NULL, NULL);
1057 if (daemonize) {
1058 if (daemon(0, 0) < 0) {
1059 error_report("Failed to daemonize: %s", strerror(errno));
1060 exit(EXIT_FAILURE);
1064 if ((daemonize || pidfile_specified) &&
1065 !qemu_write_pidfile(pidfile, &local_err)) {
1066 error_report_err(local_err);
1067 exit(EXIT_FAILURE);
1070 #ifdef CONFIG_LIBCAP_NG
1071 if (drop_privileges() < 0) {
1072 error_report("Failed to drop privileges: %s", strerror(errno));
1073 exit(EXIT_FAILURE);
1075 #endif
1077 state = RUNNING;
1078 do {
1079 main_loop_wait(false);
1080 if (state == TERMINATE) {
1081 state = TERMINATING;
1082 close_server_socket();
1084 } while (num_active_sockets > 0);
1086 exit(EXIT_SUCCESS);