| /* |
| * Privileged helper to handle persistent reservation commands for QEMU |
| * |
| * Copyright (C) 2017 Red Hat, Inc. <pbonzini@redhat.com> |
| * |
| * Author: Paolo Bonzini <pbonzini@redhat.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; under version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include <getopt.h> |
| #include <sys/ioctl.h> |
| #include <linux/dm-ioctl.h> |
| #include <scsi/sg.h> |
| |
| #ifdef CONFIG_LIBCAP |
| #include <cap-ng.h> |
| #endif |
| #include <pwd.h> |
| #include <grp.h> |
| |
| #ifdef CONFIG_MPATH |
| #include <libudev.h> |
| #include <mpath_cmd.h> |
| #include <mpath_persist.h> |
| #endif |
| |
| #include "qapi/error.h" |
| #include "qemu-common.h" |
| #include "qemu/cutils.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/error-report.h" |
| #include "qemu/config-file.h" |
| #include "qemu/bswap.h" |
| #include "qemu/log.h" |
| #include "qemu/systemd.h" |
| #include "qapi/util.h" |
| #include "qapi/qmp/qstring.h" |
| #include "io/channel-socket.h" |
| #include "trace/control.h" |
| #include "qemu-version.h" |
| |
| #include "block/aio.h" |
| #include "block/thread-pool.h" |
| |
| #include "scsi/constants.h" |
| #include "scsi/utils.h" |
| #include "pr-helper.h" |
| |
| #define PR_OUT_FIXED_PARAM_SIZE 24 |
| |
| static char *socket_path; |
| static char *pidfile; |
| static enum { RUNNING, TERMINATE, TERMINATING } state; |
| static QIOChannelSocket *server_ioc; |
| static int server_watch; |
| static int num_active_sockets = 1; |
| static int noisy; |
| static int verbose; |
| |
| #ifdef CONFIG_LIBCAP |
| static int uid = -1; |
| static int gid = -1; |
| #endif |
| |
| static void compute_default_paths(void) |
| { |
| socket_path = qemu_get_local_state_pathname("run/qemu-pr-helper.sock"); |
| pidfile = qemu_get_local_state_pathname("run/qemu-pr-helper.pid"); |
| } |
| |
| static void usage(const char *name) |
| { |
| (printf) ( |
| "Usage: %s [OPTIONS] FILE\n" |
| "Persistent Reservation helper program for QEMU\n" |
| "\n" |
| " -h, --help display this help and exit\n" |
| " -V, --version output version information and exit\n" |
| "\n" |
| " -d, --daemon run in the background\n" |
| " -f, --pidfile=PATH PID file when running as a daemon\n" |
| " (default '%s')\n" |
| " -k, --socket=PATH path to the unix socket\n" |
| " (default '%s')\n" |
| " -T, --trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" |
| " specify tracing options\n" |
| #ifdef CONFIG_LIBCAP |
| " -u, --user=USER user to drop privileges to\n" |
| " -g, --group=GROUP group to drop privileges to\n" |
| #endif |
| "\n" |
| QEMU_HELP_BOTTOM "\n" |
| , name, pidfile, socket_path); |
| } |
| |
| static void version(const char *name) |
| { |
| printf( |
| "%s " QEMU_FULL_VERSION "\n" |
| "Written by Paolo Bonzini.\n" |
| "\n" |
| QEMU_COPYRIGHT "\n" |
| "This is free software; see the source for copying conditions. There is NO\n" |
| "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n" |
| , name); |
| } |
| |
| static void write_pidfile(void) |
| { |
| int pidfd; |
| char pidstr[32]; |
| |
| pidfd = qemu_open(pidfile, O_CREAT|O_WRONLY, S_IRUSR|S_IWUSR); |
| if (pidfd == -1) { |
| error_report("Cannot open pid file, %s", strerror(errno)); |
| exit(EXIT_FAILURE); |
| } |
| |
| if (lockf(pidfd, F_TLOCK, 0)) { |
| error_report("Cannot lock pid file, %s", strerror(errno)); |
| goto fail; |
| } |
| if (ftruncate(pidfd, 0)) { |
| error_report("Failed to truncate pid file"); |
| goto fail; |
| } |
| |
| snprintf(pidstr, sizeof(pidstr), "%d\n", getpid()); |
| if (write(pidfd, pidstr, strlen(pidstr)) != strlen(pidstr)) { |
| error_report("Failed to write pid file"); |
| goto fail; |
| } |
| return; |
| |
| fail: |
| unlink(pidfile); |
| close(pidfd); |
| exit(EXIT_FAILURE); |
| } |
| |
| /* SG_IO support */ |
| |
| typedef struct PRHelperSGIOData { |
| int fd; |
| const uint8_t *cdb; |
| uint8_t *sense; |
| uint8_t *buf; |
| int sz; /* input/output */ |
| int dir; |
| } PRHelperSGIOData; |
| |
| static int do_sgio_worker(void *opaque) |
| { |
| PRHelperSGIOData *data = opaque; |
| struct sg_io_hdr io_hdr; |
| int ret; |
| int status; |
| SCSISense sense_code; |
| |
| memset(data->sense, 0, PR_HELPER_SENSE_SIZE); |
| memset(&io_hdr, 0, sizeof(io_hdr)); |
| io_hdr.interface_id = 'S'; |
| io_hdr.cmd_len = PR_HELPER_CDB_SIZE; |
| io_hdr.cmdp = (uint8_t *)data->cdb; |
| io_hdr.sbp = data->sense; |
| io_hdr.mx_sb_len = PR_HELPER_SENSE_SIZE; |
| io_hdr.timeout = 1; |
| io_hdr.dxfer_direction = data->dir; |
| io_hdr.dxferp = (char *)data->buf; |
| io_hdr.dxfer_len = data->sz; |
| ret = ioctl(data->fd, SG_IO, &io_hdr); |
| status = sg_io_sense_from_errno(ret < 0 ? errno : 0, &io_hdr, |
| &sense_code); |
| if (status == GOOD) { |
| data->sz -= io_hdr.resid; |
| } else { |
| data->sz = 0; |
| } |
| |
| if (status == CHECK_CONDITION && |
| !(io_hdr.driver_status & SG_ERR_DRIVER_SENSE)) { |
| scsi_build_sense(data->sense, sense_code); |
| } |
| |
| return status; |
| } |
| |
| static int do_sgio(int fd, const uint8_t *cdb, uint8_t *sense, |
| uint8_t *buf, int *sz, int dir) |
| { |
| ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context()); |
| int r; |
| |
| PRHelperSGIOData data = { |
| .fd = fd, |
| .cdb = cdb, |
| .sense = sense, |
| .buf = buf, |
| .sz = *sz, |
| .dir = dir, |
| }; |
| |
| r = thread_pool_submit_co(pool, do_sgio_worker, &data); |
| *sz = data.sz; |
| return r; |
| } |
| |
| /* Device mapper interface */ |
| |
| #ifdef CONFIG_MPATH |
| #define CONTROL_PATH "/dev/mapper/control" |
| |
| typedef struct DMData { |
| struct dm_ioctl dm; |
| uint8_t data[1024]; |
| } DMData; |
| |
| static int control_fd; |
| |
| static void *dm_ioctl(int ioc, struct dm_ioctl *dm) |
| { |
| static DMData d; |
| memcpy(&d.dm, dm, sizeof(d.dm)); |
| QEMU_BUILD_BUG_ON(sizeof(d.data) < sizeof(struct dm_target_spec)); |
| |
| d.dm.version[0] = DM_VERSION_MAJOR; |
| d.dm.version[1] = 0; |
| d.dm.version[2] = 0; |
| d.dm.data_size = 1024; |
| d.dm.data_start = offsetof(DMData, data); |
| if (ioctl(control_fd, ioc, &d) < 0) { |
| return NULL; |
| } |
| memcpy(dm, &d.dm, sizeof(d.dm)); |
| return &d.data; |
| } |
| |
| static void *dm_dev_ioctl(int fd, int ioc, struct dm_ioctl *dm) |
| { |
| struct stat st; |
| int r; |
| |
| r = fstat(fd, &st); |
| if (r < 0) { |
| perror("fstat"); |
| exit(1); |
| } |
| |
| dm->dev = st.st_rdev; |
| return dm_ioctl(ioc, dm); |
| } |
| |
| static void dm_init(void) |
| { |
| control_fd = open(CONTROL_PATH, O_RDWR); |
| if (control_fd < 0) { |
| perror("Cannot open " CONTROL_PATH); |
| exit(1); |
| } |
| struct dm_ioctl dm = { 0 }; |
| if (!dm_ioctl(DM_VERSION, &dm)) { |
| perror("ioctl"); |
| exit(1); |
| } |
| if (dm.version[0] != DM_VERSION_MAJOR) { |
| fprintf(stderr, "Unsupported device mapper interface"); |
| exit(1); |
| } |
| } |
| |
| /* Variables required by libmultipath and libmpathpersist. */ |
| QEMU_BUILD_BUG_ON(PR_HELPER_DATA_SIZE > MPATH_MAX_PARAM_LEN); |
| static struct config *multipath_conf; |
| unsigned mpath_mx_alloc_len = PR_HELPER_DATA_SIZE; |
| int logsink; |
| struct udev *udev; |
| |
| extern struct config *get_multipath_config(void); |
| struct config *get_multipath_config(void) |
| { |
| return multipath_conf; |
| } |
| |
| extern void put_multipath_config(struct config *conf); |
| void put_multipath_config(struct config *conf) |
| { |
| } |
| |
| static void multipath_pr_init(void) |
| { |
| udev = udev_new(); |
| #ifdef CONFIG_MPATH_NEW_API |
| multipath_conf = mpath_lib_init(); |
| #else |
| mpath_lib_init(udev); |
| #endif |
| } |
| |
| static int is_mpath(int fd) |
| { |
| struct dm_ioctl dm = { .flags = DM_NOFLUSH_FLAG }; |
| struct dm_target_spec *tgt; |
| |
| tgt = dm_dev_ioctl(fd, DM_TABLE_STATUS, &dm); |
| if (!tgt) { |
| if (errno == ENXIO) { |
| return 0; |
| } |
| perror("ioctl"); |
| exit(EXIT_FAILURE); |
| } |
| return !strncmp(tgt->target_type, "multipath", DM_MAX_TYPE_NAME); |
| } |
| |
| static SCSISense mpath_generic_sense(int r) |
| { |
| switch (r) { |
| case MPATH_PR_SENSE_NOT_READY: |
| return SENSE_CODE(NOT_READY); |
| case MPATH_PR_SENSE_MEDIUM_ERROR: |
| return SENSE_CODE(READ_ERROR); |
| case MPATH_PR_SENSE_HARDWARE_ERROR: |
| return SENSE_CODE(TARGET_FAILURE); |
| case MPATH_PR_SENSE_ABORTED_COMMAND: |
| return SENSE_CODE(IO_ERROR); |
| default: |
| abort(); |
| } |
| } |
| |
| static int mpath_reconstruct_sense(int fd, int r, uint8_t *sense) |
| { |
| switch (r) { |
| case MPATH_PR_SUCCESS: |
| return GOOD; |
| case MPATH_PR_SENSE_NOT_READY: |
| case MPATH_PR_SENSE_MEDIUM_ERROR: |
| case MPATH_PR_SENSE_HARDWARE_ERROR: |
| case MPATH_PR_SENSE_ABORTED_COMMAND: |
| { |
| /* libmpathpersist ate the exact sense. Try to find it by |
| * issuing TEST UNIT READY. |
| */ |
| uint8_t cdb[6] = { TEST_UNIT_READY }; |
| int sz = 0; |
| int r = do_sgio(fd, cdb, sense, NULL, &sz, SG_DXFER_NONE); |
| |
| if (r != GOOD) { |
| return r; |
| } |
| scsi_build_sense(sense, mpath_generic_sense(r)); |
| return CHECK_CONDITION; |
| } |
| |
| case MPATH_PR_SENSE_UNIT_ATTENTION: |
| /* Congratulations libmpathpersist, you ruined the Unit Attention... |
| * Return a heavyweight one. |
| */ |
| scsi_build_sense(sense, SENSE_CODE(SCSI_BUS_RESET)); |
| return CHECK_CONDITION; |
| case MPATH_PR_SENSE_INVALID_OP: |
| /* Only one valid sense. */ |
| scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE)); |
| return CHECK_CONDITION; |
| case MPATH_PR_ILLEGAL_REQ: |
| /* Guess. */ |
| scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM)); |
| return CHECK_CONDITION; |
| case MPATH_PR_NO_SENSE: |
| scsi_build_sense(sense, SENSE_CODE(NO_SENSE)); |
| return CHECK_CONDITION; |
| |
| case MPATH_PR_RESERV_CONFLICT: |
| return RESERVATION_CONFLICT; |
| |
| case MPATH_PR_OTHER: |
| default: |
| scsi_build_sense(sense, SENSE_CODE(LUN_COMM_FAILURE)); |
| return CHECK_CONDITION; |
| } |
| } |
| |
| static int multipath_pr_in(int fd, const uint8_t *cdb, uint8_t *sense, |
| uint8_t *data, int sz) |
| { |
| int rq_servact = cdb[1]; |
| struct prin_resp resp; |
| size_t written; |
| int r; |
| |
| switch (rq_servact) { |
| case MPATH_PRIN_RKEY_SA: |
| case MPATH_PRIN_RRES_SA: |
| case MPATH_PRIN_RCAP_SA: |
| break; |
| case MPATH_PRIN_RFSTAT_SA: |
| /* Nobody implements it anyway, so bail out. */ |
| default: |
| /* Cannot parse any other output. */ |
| scsi_build_sense(sense, SENSE_CODE(INVALID_FIELD)); |
| return CHECK_CONDITION; |
| } |
| |
| r = mpath_persistent_reserve_in(fd, rq_servact, &resp, noisy, verbose); |
| if (r == MPATH_PR_SUCCESS) { |
| switch (rq_servact) { |
| case MPATH_PRIN_RKEY_SA: |
| case MPATH_PRIN_RRES_SA: { |
| struct prin_readdescr *out = &resp.prin_descriptor.prin_readkeys; |
| assert(sz >= 8); |
| written = MIN(out->additional_length + 8, sz); |
| stl_be_p(&data[0], out->prgeneration); |
| stl_be_p(&data[4], out->additional_length); |
| memcpy(&data[8], out->key_list, written - 8); |
| break; |
| } |
| case MPATH_PRIN_RCAP_SA: { |
| struct prin_capdescr *out = &resp.prin_descriptor.prin_readcap; |
| assert(sz >= 6); |
| written = 6; |
| stw_be_p(&data[0], out->length); |
| data[2] = out->flags[0]; |
| data[3] = out->flags[1]; |
| stw_be_p(&data[4], out->pr_type_mask); |
| break; |
| } |
| default: |
| scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE)); |
| return CHECK_CONDITION; |
| } |
| assert(written <= sz); |
| memset(data + written, 0, sz - written); |
| } |
| |
| return mpath_reconstruct_sense(fd, r, sense); |
| } |
| |
| static int multipath_pr_out(int fd, const uint8_t *cdb, uint8_t *sense, |
| const uint8_t *param, int sz) |
| { |
| int rq_servact = cdb[1]; |
| int rq_scope = cdb[2] >> 4; |
| int rq_type = cdb[2] & 0xf; |
| struct prout_param_descriptor paramp; |
| char transportids[PR_HELPER_DATA_SIZE]; |
| int r; |
| |
| if (sz < PR_OUT_FIXED_PARAM_SIZE) { |
| /* Illegal request, Parameter list length error. This isn't fatal; |
| * we have read the data, send an error without closing the socket. |
| */ |
| scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM_LEN)); |
| return CHECK_CONDITION; |
| } |
| |
| switch (rq_servact) { |
| case MPATH_PROUT_REG_SA: |
| case MPATH_PROUT_RES_SA: |
| case MPATH_PROUT_REL_SA: |
| case MPATH_PROUT_CLEAR_SA: |
| case MPATH_PROUT_PREE_SA: |
| case MPATH_PROUT_PREE_AB_SA: |
| case MPATH_PROUT_REG_IGN_SA: |
| break; |
| case MPATH_PROUT_REG_MOV_SA: |
| /* Not supported by struct prout_param_descriptor. */ |
| default: |
| /* Cannot parse any other input. */ |
| scsi_build_sense(sense, SENSE_CODE(INVALID_FIELD)); |
| return CHECK_CONDITION; |
| } |
| |
| /* Convert input data, especially transport IDs, to the structs |
| * used by libmpathpersist (which, of course, will immediately |
| * do the opposite). |
| */ |
| memset(¶mp, 0, sizeof(paramp)); |
| memcpy(¶mp.key, ¶m[0], 8); |
| memcpy(¶mp.sa_key, ¶m[8], 8); |
| paramp.sa_flags = param[20]; |
| if (sz > PR_OUT_FIXED_PARAM_SIZE) { |
| size_t transportid_len; |
| int i, j; |
| if (sz < PR_OUT_FIXED_PARAM_SIZE + 4) { |
| scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM_LEN)); |
| return CHECK_CONDITION; |
| } |
| transportid_len = ldl_be_p(¶m[24]) + PR_OUT_FIXED_PARAM_SIZE + 4; |
| if (transportid_len > sz) { |
| scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM)); |
| return CHECK_CONDITION; |
| } |
| for (i = PR_OUT_FIXED_PARAM_SIZE + 4, j = 0; i < transportid_len; ) { |
| struct transportid *id = (struct transportid *) &transportids[j]; |
| int len; |
| |
| id->format_code = param[i] & 0xc0; |
| id->protocol_id = param[i] & 0x0f; |
| switch (param[i] & 0xcf) { |
| case 0: |
| /* FC transport. */ |
| if (i + 24 > transportid_len) { |
| goto illegal_req; |
| } |
| memcpy(id->n_port_name, ¶m[i + 8], 8); |
| j += offsetof(struct transportid, n_port_name[8]); |
| i += 24; |
| break; |
| case 5: |
| case 0x45: |
| /* iSCSI transport. */ |
| len = lduw_be_p(¶m[i + 2]); |
| if (len > 252 || (len & 3) || i + len + 4 > transportid_len) { |
| /* For format code 00, the standard says the maximum is 223 |
| * plus the NUL terminator. For format code 01 there is no |
| * maximum length, but libmpathpersist ignores the first |
| * byte of id->iscsi_name so our maximum is 252. |
| */ |
| goto illegal_req; |
| } |
| if (memchr(¶m[i + 4], 0, len) == NULL) { |
| goto illegal_req; |
| } |
| memcpy(id->iscsi_name, ¶m[i + 2], len + 2); |
| j += offsetof(struct transportid, iscsi_name[len + 2]); |
| i += len + 4; |
| break; |
| case 6: |
| /* SAS transport. */ |
| if (i + 24 > transportid_len) { |
| goto illegal_req; |
| } |
| memcpy(id->sas_address, ¶m[i + 4], 8); |
| j += offsetof(struct transportid, sas_address[8]); |
| i += 24; |
| break; |
| default: |
| illegal_req: |
| scsi_build_sense(sense, SENSE_CODE(INVALID_PARAM)); |
| return CHECK_CONDITION; |
| } |
| |
| paramp.trnptid_list[paramp.num_transportid++] = id; |
| } |
| } |
| |
| r = mpath_persistent_reserve_out(fd, rq_servact, rq_scope, rq_type, |
| ¶mp, noisy, verbose); |
| return mpath_reconstruct_sense(fd, r, sense); |
| } |
| #endif |
| |
| static int do_pr_in(int fd, const uint8_t *cdb, uint8_t *sense, |
| uint8_t *data, int *resp_sz) |
| { |
| #ifdef CONFIG_MPATH |
| if (is_mpath(fd)) { |
| /* multipath_pr_in fills the whole input buffer. */ |
| int r = multipath_pr_in(fd, cdb, sense, data, *resp_sz); |
| if (r != GOOD) { |
| *resp_sz = 0; |
| } |
| return r; |
| } |
| #endif |
| |
| return do_sgio(fd, cdb, sense, data, resp_sz, |
| SG_DXFER_FROM_DEV); |
| } |
| |
| static int do_pr_out(int fd, const uint8_t *cdb, uint8_t *sense, |
| const uint8_t *param, int sz) |
| { |
| int resp_sz; |
| |
| if ((fcntl(fd, F_GETFL) & O_ACCMODE) == O_RDONLY) { |
| scsi_build_sense(sense, SENSE_CODE(INVALID_OPCODE)); |
| return CHECK_CONDITION; |
| } |
| |
| #ifdef CONFIG_MPATH |
| if (is_mpath(fd)) { |
| return multipath_pr_out(fd, cdb, sense, param, sz); |
| } |
| #endif |
| |
| resp_sz = sz; |
| return do_sgio(fd, cdb, sense, (uint8_t *)param, &resp_sz, |
| SG_DXFER_TO_DEV); |
| } |
| |
| /* Client */ |
| |
| typedef struct PRHelperClient { |
| QIOChannelSocket *ioc; |
| Coroutine *co; |
| int fd; |
| uint8_t data[PR_HELPER_DATA_SIZE]; |
| } PRHelperClient; |
| |
| typedef struct PRHelperRequest { |
| int fd; |
| size_t sz; |
| uint8_t cdb[PR_HELPER_CDB_SIZE]; |
| } PRHelperRequest; |
| |
| static int coroutine_fn prh_read(PRHelperClient *client, void *buf, int sz, |
| Error **errp) |
| { |
| int ret = 0; |
| |
| while (sz > 0) { |
| int *fds = NULL; |
| size_t nfds = 0; |
| int i; |
| struct iovec iov; |
| ssize_t n_read; |
| |
| iov.iov_base = buf; |
| iov.iov_len = sz; |
| n_read = qio_channel_readv_full(QIO_CHANNEL(client->ioc), &iov, 1, |
| &fds, &nfds, errp); |
| |
| if (n_read == QIO_CHANNEL_ERR_BLOCK) { |
| qio_channel_yield(QIO_CHANNEL(client->ioc), G_IO_IN); |
| continue; |
| } |
| if (n_read <= 0) { |
| ret = n_read ? n_read : -1; |
| goto err; |
| } |
| |
| /* Stash one file descriptor per request. */ |
| if (nfds) { |
| bool too_many = false; |
| for (i = 0; i < nfds; i++) { |
| if (client->fd == -1) { |
| client->fd = fds[i]; |
| } else { |
| close(fds[i]); |
| too_many = true; |
| } |
| } |
| g_free(fds); |
| if (too_many) { |
| ret = -1; |
| goto err; |
| } |
| } |
| |
| buf += n_read; |
| sz -= n_read; |
| } |
| |
| return 0; |
| |
| err: |
| if (client->fd != -1) { |
| close(client->fd); |
| client->fd = -1; |
| } |
| return ret; |
| } |
| |
| static int coroutine_fn prh_read_request(PRHelperClient *client, |
| PRHelperRequest *req, |
| PRHelperResponse *resp, Error **errp) |
| { |
| uint32_t sz; |
| |
| if (prh_read(client, req->cdb, sizeof(req->cdb), NULL) < 0) { |
| return -1; |
| } |
| |
| if (client->fd == -1) { |
| error_setg(errp, "No file descriptor in request."); |
| return -1; |
| } |
| |
| if (req->cdb[0] != PERSISTENT_RESERVE_OUT && |
| req->cdb[0] != PERSISTENT_RESERVE_IN) { |
| error_setg(errp, "Invalid CDB, closing socket."); |
| goto out_close; |
| } |
| |
| sz = scsi_cdb_xfer(req->cdb); |
| if (sz > sizeof(client->data)) { |
| goto out_close; |
| } |
| |
| if (req->cdb[0] == PERSISTENT_RESERVE_OUT) { |
| if (qio_channel_read_all(QIO_CHANNEL(client->ioc), |
| (char *)client->data, sz, |
| errp) < 0) { |
| goto out_close; |
| } |
| } |
| |
| req->fd = client->fd; |
| req->sz = sz; |
| client->fd = -1; |
| return sz; |
| |
| out_close: |
| close(client->fd); |
| client->fd = -1; |
| return -1; |
| } |
| |
| static int coroutine_fn prh_write_response(PRHelperClient *client, |
| PRHelperRequest *req, |
| PRHelperResponse *resp, Error **errp) |
| { |
| ssize_t r; |
| size_t sz; |
| |
| if (req->cdb[0] == PERSISTENT_RESERVE_IN && resp->result == GOOD) { |
| assert(resp->sz <= req->sz && resp->sz <= sizeof(client->data)); |
| } else { |
| assert(resp->sz == 0); |
| } |
| |
| sz = resp->sz; |
| |
| resp->result = cpu_to_be32(resp->result); |
| resp->sz = cpu_to_be32(resp->sz); |
| r = qio_channel_write_all(QIO_CHANNEL(client->ioc), |
| (char *) resp, sizeof(*resp), errp); |
| if (r < 0) { |
| return r; |
| } |
| |
| r = qio_channel_write_all(QIO_CHANNEL(client->ioc), |
| (char *) client->data, |
| sz, errp); |
| return r < 0 ? r : 0; |
| } |
| |
| static void coroutine_fn prh_co_entry(void *opaque) |
| { |
| PRHelperClient *client = opaque; |
| Error *local_err = NULL; |
| uint32_t flags; |
| int r; |
| |
| qio_channel_set_blocking(QIO_CHANNEL(client->ioc), |
| false, NULL); |
| qio_channel_attach_aio_context(QIO_CHANNEL(client->ioc), |
| qemu_get_aio_context()); |
| |
| /* A very simple negotiation for future extensibility. No features |
| * are defined so write 0. |
| */ |
| flags = cpu_to_be32(0); |
| r = qio_channel_write_all(QIO_CHANNEL(client->ioc), |
| (char *) &flags, sizeof(flags), NULL); |
| if (r < 0) { |
| goto out; |
| } |
| |
| r = qio_channel_read_all(QIO_CHANNEL(client->ioc), |
| (char *) &flags, sizeof(flags), NULL); |
| if (be32_to_cpu(flags) != 0 || r < 0) { |
| goto out; |
| } |
| |
| while (atomic_read(&state) == RUNNING) { |
| PRHelperRequest req; |
| PRHelperResponse resp; |
| int sz; |
| |
| sz = prh_read_request(client, &req, &resp, &local_err); |
| if (sz < 0) { |
| break; |
| } |
| |
| num_active_sockets++; |
| if (req.cdb[0] == PERSISTENT_RESERVE_OUT) { |
| r = do_pr_out(req.fd, req.cdb, resp.sense, |
| client->data, sz); |
| resp.sz = 0; |
| } else { |
| resp.sz = sizeof(client->data); |
| r = do_pr_in(req.fd, req.cdb, resp.sense, |
| client->data, &resp.sz); |
| resp.sz = MIN(resp.sz, sz); |
| } |
| num_active_sockets--; |
| close(req.fd); |
| if (r == -1) { |
| break; |
| } |
| resp.result = r; |
| |
| if (prh_write_response(client, &req, &resp, &local_err) < 0) { |
| break; |
| } |
| } |
| |
| if (local_err) { |
| if (verbose == 0) { |
| error_free(local_err); |
| } else { |
| error_report_err(local_err); |
| } |
| } |
| |
| out: |
| qio_channel_detach_aio_context(QIO_CHANNEL(client->ioc)); |
| object_unref(OBJECT(client->ioc)); |
| g_free(client); |
| } |
| |
| static gboolean accept_client(QIOChannel *ioc, GIOCondition cond, gpointer opaque) |
| { |
| QIOChannelSocket *cioc; |
| PRHelperClient *prh; |
| |
| cioc = qio_channel_socket_accept(QIO_CHANNEL_SOCKET(ioc), |
| NULL); |
| if (!cioc) { |
| return TRUE; |
| } |
| |
| prh = g_new(PRHelperClient, 1); |
| prh->ioc = cioc; |
| prh->fd = -1; |
| prh->co = qemu_coroutine_create(prh_co_entry, prh); |
| qemu_coroutine_enter(prh->co); |
| |
| return TRUE; |
| } |
| |
| static void termsig_handler(int signum) |
| { |
| atomic_cmpxchg(&state, RUNNING, TERMINATE); |
| qemu_notify_event(); |
| } |
| |
| static void close_server_socket(void) |
| { |
| assert(server_ioc); |
| |
| g_source_remove(server_watch); |
| server_watch = -1; |
| object_unref(OBJECT(server_ioc)); |
| num_active_sockets--; |
| } |
| |
| #ifdef CONFIG_LIBCAP |
| static int drop_privileges(void) |
| { |
| /* clear all capabilities */ |
| capng_clear(CAPNG_SELECT_BOTH); |
| |
| if (capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED, |
| CAP_SYS_RAWIO) < 0) { |
| return -1; |
| } |
| |
| #ifdef CONFIG_MPATH |
| /* For /dev/mapper/control ioctls */ |
| if (capng_update(CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED, |
| CAP_SYS_ADMIN) < 0) { |
| return -1; |
| } |
| #endif |
| |
| /* Change user/group id, retaining the capabilities. Because file descriptors |
| * are passed via SCM_RIGHTS, we don't need supplementary groups (and in |
| * fact the helper can run as "nobody"). |
| */ |
| if (capng_change_id(uid != -1 ? uid : getuid(), |
| gid != -1 ? gid : getgid(), |
| CAPNG_DROP_SUPP_GRP | CAPNG_CLEAR_BOUNDING)) { |
| return -1; |
| } |
| |
| return 0; |
| } |
| #endif |
| |
| int main(int argc, char **argv) |
| { |
| const char *sopt = "hVk:f:dT:u:g:vq"; |
| struct option lopt[] = { |
| { "help", no_argument, NULL, 'h' }, |
| { "version", no_argument, NULL, 'V' }, |
| { "socket", required_argument, NULL, 'k' }, |
| { "pidfile", required_argument, NULL, 'f' }, |
| { "daemon", no_argument, NULL, 'd' }, |
| { "trace", required_argument, NULL, 'T' }, |
| { "user", required_argument, NULL, 'u' }, |
| { "group", required_argument, NULL, 'g' }, |
| { "verbose", no_argument, NULL, 'v' }, |
| { "quiet", no_argument, NULL, 'q' }, |
| { NULL, 0, NULL, 0 } |
| }; |
| int opt_ind = 0; |
| int loglevel = 1; |
| int quiet = 0; |
| int ch; |
| Error *local_err = NULL; |
| char *trace_file = NULL; |
| bool daemonize = false; |
| bool pidfile_specified = false; |
| bool socket_path_specified = false; |
| unsigned socket_activation; |
| |
| struct sigaction sa_sigterm; |
| memset(&sa_sigterm, 0, sizeof(sa_sigterm)); |
| sa_sigterm.sa_handler = termsig_handler; |
| sigaction(SIGTERM, &sa_sigterm, NULL); |
| sigaction(SIGINT, &sa_sigterm, NULL); |
| sigaction(SIGHUP, &sa_sigterm, NULL); |
| |
| signal(SIGPIPE, SIG_IGN); |
| |
| module_call_init(MODULE_INIT_TRACE); |
| module_call_init(MODULE_INIT_QOM); |
| qemu_add_opts(&qemu_trace_opts); |
| qemu_init_exec_dir(argv[0]); |
| |
| compute_default_paths(); |
| |
| while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { |
| switch (ch) { |
| case 'k': |
| g_free(socket_path); |
| socket_path = g_strdup(optarg); |
| socket_path_specified = true; |
| if (socket_path[0] != '/') { |
| error_report("socket path must be absolute"); |
| exit(EXIT_FAILURE); |
| } |
| break; |
| case 'f': |
| g_free(pidfile); |
| pidfile = g_strdup(optarg); |
| pidfile_specified = true; |
| break; |
| #ifdef CONFIG_LIBCAP |
| case 'u': { |
| unsigned long res; |
| struct passwd *userinfo = getpwnam(optarg); |
| if (userinfo) { |
| uid = userinfo->pw_uid; |
| } else if (qemu_strtoul(optarg, NULL, 10, &res) == 0 && |
| (uid_t)res == res) { |
| uid = res; |
| } else { |
| error_report("invalid user '%s'", optarg); |
| exit(EXIT_FAILURE); |
| } |
| break; |
| } |
| case 'g': { |
| unsigned long res; |
| struct group *groupinfo = getgrnam(optarg); |
| if (groupinfo) { |
| gid = groupinfo->gr_gid; |
| } else if (qemu_strtoul(optarg, NULL, 10, &res) == 0 && |
| (gid_t)res == res) { |
| gid = res; |
| } else { |
| error_report("invalid group '%s'", optarg); |
| exit(EXIT_FAILURE); |
| } |
| break; |
| } |
| #else |
| case 'u': |
| case 'g': |
| error_report("-%c not supported by this %s", ch, argv[0]); |
| exit(1); |
| #endif |
| case 'd': |
| daemonize = true; |
| break; |
| case 'q': |
| quiet = 1; |
| break; |
| case 'v': |
| ++loglevel; |
| break; |
| case 'T': |
| g_free(trace_file); |
| trace_file = trace_opt_parse(optarg); |
| break; |
| case 'V': |
| version(argv[0]); |
| exit(EXIT_SUCCESS); |
| break; |
| case 'h': |
| usage(argv[0]); |
| exit(EXIT_SUCCESS); |
| break; |
| case '?': |
| error_report("Try `%s --help' for more information.", argv[0]); |
| exit(EXIT_FAILURE); |
| } |
| } |
| |
| /* set verbosity */ |
| noisy = !quiet && (loglevel >= 3); |
| verbose = quiet ? 0 : MIN(loglevel, 3); |
| |
| if (!trace_init_backends()) { |
| exit(EXIT_FAILURE); |
| } |
| trace_init_file(trace_file); |
| qemu_set_log(LOG_TRACE); |
| |
| #ifdef CONFIG_MPATH |
| dm_init(); |
| multipath_pr_init(); |
| #endif |
| |
| socket_activation = check_socket_activation(); |
| if (socket_activation == 0) { |
| SocketAddress saddr; |
| saddr = (SocketAddress){ |
| .type = SOCKET_ADDRESS_TYPE_UNIX, |
| .u.q_unix.path = socket_path, |
| }; |
| server_ioc = qio_channel_socket_new(); |
| if (qio_channel_socket_listen_sync(server_ioc, &saddr, &local_err) < 0) { |
| object_unref(OBJECT(server_ioc)); |
| error_report_err(local_err); |
| return 1; |
| } |
| } else { |
| /* Using socket activation - check user didn't use -p etc. */ |
| if (socket_path_specified) { |
| error_report("Unix socket can't be set when using socket activation"); |
| exit(EXIT_FAILURE); |
| } |
| |
| /* Can only listen on a single socket. */ |
| if (socket_activation > 1) { |
| error_report("%s does not support socket activation with LISTEN_FDS > 1", |
| argv[0]); |
| exit(EXIT_FAILURE); |
| } |
| server_ioc = qio_channel_socket_new_fd(FIRST_SOCKET_ACTIVATION_FD, |
| &local_err); |
| if (server_ioc == NULL) { |
| error_report("Failed to use socket activation: %s", |
| error_get_pretty(local_err)); |
| exit(EXIT_FAILURE); |
| } |
| } |
| |
| if (qemu_init_main_loop(&local_err)) { |
| error_report_err(local_err); |
| exit(EXIT_FAILURE); |
| } |
| |
| server_watch = qio_channel_add_watch(QIO_CHANNEL(server_ioc), |
| G_IO_IN, |
| accept_client, |
| NULL, NULL); |
| |
| if (daemonize) { |
| if (daemon(0, 0) < 0) { |
| error_report("Failed to daemonize: %s", strerror(errno)); |
| exit(EXIT_FAILURE); |
| } |
| } |
| |
| if (daemonize || pidfile_specified) |
| write_pidfile(); |
| |
| #ifdef CONFIG_LIBCAP |
| if (drop_privileges() < 0) { |
| error_report("Failed to drop privileges: %s", strerror(errno)); |
| exit(EXIT_FAILURE); |
| } |
| #endif |
| |
| state = RUNNING; |
| do { |
| main_loop_wait(false); |
| if (state == TERMINATE) { |
| state = TERMINATING; |
| close_server_socket(); |
| } |
| } while (num_active_sockets > 0); |
| |
| exit(EXIT_SUCCESS); |
| } |