diff options
Diffstat (limited to 'qemu-ga.c')
| -rw-r--r-- | qemu-ga.c | 650 |
1 files changed, 650 insertions, 0 deletions
diff --git a/qemu-ga.c b/qemu-ga.c new file mode 100644 index 0000000000..1f3585c51e --- /dev/null +++ b/qemu-ga.c @@ -0,0 +1,650 @@ +/* + * QEMU Guest Agent + * + * Copyright IBM Corp. 2011 + * + * Authors: + * Adam Litke <aglitke@linux.vnet.ibm.com> + * Michael Roth <mdroth@linux.vnet.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ +#include <stdlib.h> +#include <stdio.h> +#include <stdbool.h> +#include <glib.h> +#include <gio/gio.h> +#include <getopt.h> +#include <termios.h> +#include <syslog.h> +#include "qemu_socket.h" +#include "json-streamer.h" +#include "json-parser.h" +#include "qint.h" +#include "qjson.h" +#include "qga/guest-agent-core.h" +#include "module.h" +#include "signal.h" +#include "qerror.h" +#include "error_int.h" + +#define QGA_VIRTIO_PATH_DEFAULT "/dev/virtio-ports/org.qemu.guest_agent.0" +#define QGA_PIDFILE_DEFAULT "/var/run/qemu-ga.pid" +#define QGA_BAUDRATE_DEFAULT B38400 /* for isa-serial channels */ +#define QGA_TIMEOUT_DEFAULT 30*1000 /* ms */ + +struct GAState { + JSONMessageParser parser; + GMainLoop *main_loop; + GSocket *conn_sock; + GIOChannel *conn_channel; + GSocket *listen_sock; + GIOChannel *listen_channel; + const char *path; + const char *method; + bool virtio; /* fastpath to check for virtio to deal with poll() quirks */ + GACommandState *command_state; + GLogLevelFlags log_level; + FILE *log_file; + bool logging_enabled; +}; + +static struct GAState *ga_state; + +static void quit_handler(int sig) +{ + g_debug("recieved signal num %d, quitting", sig); + + if (g_main_loop_is_running(ga_state->main_loop)) { + g_main_loop_quit(ga_state->main_loop); + } +} + +static void register_signal_handlers(void) +{ + struct sigaction sigact; + int ret; + + memset(&sigact, 0, sizeof(struct sigaction)); + sigact.sa_handler = quit_handler; + + ret = sigaction(SIGINT, &sigact, NULL); + if (ret == -1) { + g_error("error configuring signal handler: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + ret = sigaction(SIGTERM, &sigact, NULL); + if (ret == -1) { + g_error("error configuring signal handler: %s", strerror(errno)); + } +} + +static void usage(const char *cmd) +{ + printf( +"Usage: %s -c <channel_opts>\n" +"QEMU Guest Agent %s\n" +"\n" +" -m, --method transport method: one of unix-listen, virtio-serial, or\n" +" isa-serial (virtio-serial is the default)\n" +" -p, --path device/socket path (%s is the default for virtio-serial)\n" +" -l, --logfile set logfile path, logs to stderr by default\n" +" -f, --pidfile specify pidfile (default is %s)\n" +" -v, --verbose log extra debugging information\n" +" -V, --version print version information and exit\n" +" -d, --daemonize become a daemon\n" +" -h, --help display this help and exit\n" +"\n" +"Report bugs to <mdroth@linux.vnet.ibm.com>\n" + , cmd, QGA_VERSION, QGA_VIRTIO_PATH_DEFAULT, QGA_PIDFILE_DEFAULT); +} + +static void conn_channel_close(GAState *s); + +static const char *ga_log_level_str(GLogLevelFlags level) +{ + switch (level & G_LOG_LEVEL_MASK) { + case G_LOG_LEVEL_ERROR: + return "error"; + case G_LOG_LEVEL_CRITICAL: + return "critical"; + case G_LOG_LEVEL_WARNING: + return "warning"; + case G_LOG_LEVEL_MESSAGE: + return "message"; + case G_LOG_LEVEL_INFO: + return "info"; + case G_LOG_LEVEL_DEBUG: + return "debug"; + default: + return "user"; + } +} + +bool ga_logging_enabled(GAState *s) +{ + return s->logging_enabled; +} + +void ga_disable_logging(GAState *s) +{ + s->logging_enabled = false; +} + +void ga_enable_logging(GAState *s) +{ + s->logging_enabled = true; +} + +static void ga_log(const gchar *domain, GLogLevelFlags level, + const gchar *msg, gpointer opaque) +{ + GAState *s = opaque; + GTimeVal time; + const char *level_str = ga_log_level_str(level); + + if (!ga_logging_enabled(s)) { + return; + } + + level &= G_LOG_LEVEL_MASK; + if (g_strcmp0(domain, "syslog") == 0) { + syslog(LOG_INFO, "%s: %s", level_str, msg); + } else if (level & s->log_level) { + g_get_current_time(&time); + fprintf(s->log_file, + "%lu.%lu: %s: %s\n", time.tv_sec, time.tv_usec, level_str, msg); + fflush(s->log_file); + } +} + +static void become_daemon(const char *pidfile) +{ + pid_t pid, sid; + int pidfd; + char *pidstr = NULL; + + pid = fork(); + if (pid < 0) { + exit(EXIT_FAILURE); + } + if (pid > 0) { + exit(EXIT_SUCCESS); + } + + pidfd = open(pidfile, O_CREAT|O_WRONLY|O_EXCL, S_IRUSR|S_IWUSR); + if (pidfd == -1) { + g_critical("Cannot create pid file, %s", strerror(errno)); + exit(EXIT_FAILURE); + } + + if (asprintf(&pidstr, "%d", getpid()) == -1) { + g_critical("Cannot allocate memory"); + goto fail; + } + if (write(pidfd, pidstr, strlen(pidstr)) != strlen(pidstr)) { + free(pidstr); + g_critical("Failed to write pid file"); + goto fail; + } + + umask(0); + sid = setsid(); + if (sid < 0) { + goto fail; + } + if ((chdir("/")) < 0) { + goto fail; + } + + close(STDIN_FILENO); + close(STDOUT_FILENO); + close(STDERR_FILENO); + free(pidstr); + return; + +fail: + unlink(pidfile); + g_critical("failed to daemonize"); + exit(EXIT_FAILURE); +} + +static int conn_channel_send_buf(GIOChannel *channel, const char *buf, + gsize count) +{ + GError *err = NULL; + gsize written = 0; + GIOStatus status; + + while (count) { + status = g_io_channel_write_chars(channel, buf, count, &written, &err); + g_debug("sending data, count: %d", (int)count); + if (err != NULL) { + g_warning("error sending newline: %s", err->message); + return err->code; + } + if (status == G_IO_STATUS_ERROR || status == G_IO_STATUS_EOF) { + return -EPIPE; + } + + if (status == G_IO_STATUS_NORMAL) { + count -= written; + } + } + + return 0; +} + +static int conn_channel_send_payload(GIOChannel *channel, QObject *payload) +{ + int ret = 0; + const char *buf; + QString *payload_qstr; + GError *err = NULL; + + g_assert(payload && channel); + + payload_qstr = qobject_to_json(payload); + if (!payload_qstr) { + return -EINVAL; + } + + qstring_append_chr(payload_qstr, '\n'); + buf = qstring_get_str(payload_qstr); + ret = conn_channel_send_buf(channel, buf, strlen(buf)); + if (ret) { + goto out_free; + } + + g_io_channel_flush(channel, &err); + if (err != NULL) { + g_warning("error flushing payload: %s", err->message); + ret = err->code; + goto out_free; + } + +out_free: + QDECREF(payload_qstr); + if (err) { + g_error_free(err); + } + return ret; +} + +static void process_command(GAState *s, QDict *req) +{ + QObject *rsp = NULL; + int ret; + + g_assert(req); + g_debug("processing command"); + rsp = qmp_dispatch(QOBJECT(req)); + if (rsp) { + ret = conn_channel_send_payload(s->conn_channel, rsp); + if (ret) { + g_warning("error sending payload: %s", strerror(ret)); + } + qobject_decref(rsp); + } else { + g_warning("error getting response"); + } +} + +/* handle requests/control events coming in over the channel */ +static void process_event(JSONMessageParser *parser, QList *tokens) +{ + GAState *s = container_of(parser, GAState, parser); + QObject *obj; + QDict *qdict; + Error *err = NULL; + int ret; + + g_assert(s && parser); + + g_debug("process_event: called"); + obj = json_parser_parse_err(tokens, NULL, &err); + if (err || !obj || qobject_type(obj) != QTYPE_QDICT) { + qobject_decref(obj); + qdict = qdict_new(); + if (!err) { + g_warning("failed to parse event: unknown error"); + error_set(&err, QERR_JSON_PARSING); + } else { + g_warning("failed to parse event: %s", error_get_pretty(err)); + } + qdict_put_obj(qdict, "error", error_get_qobject(err)); + error_free(err); + } else { + qdict = qobject_to_qdict(obj); + } + + g_assert(qdict); + + /* handle host->guest commands */ + if (qdict_haskey(qdict, "execute")) { + process_command(s, qdict); + } else { + if (!qdict_haskey(qdict, "error")) { + QDECREF(qdict); + qdict = qdict_new(); + g_warning("unrecognized payload format"); + error_set(&err, QERR_UNSUPPORTED); + qdict_put_obj(qdict, "error", error_get_qobject(err)); + error_free(err); + } + ret = conn_channel_send_payload(s->conn_channel, QOBJECT(qdict)); + if (ret) { + g_warning("error sending payload: %s", strerror(ret)); + } + } + + QDECREF(qdict); +} + +static gboolean conn_channel_read(GIOChannel *channel, GIOCondition condition, + gpointer data) +{ + GAState *s = data; + gchar buf[1024]; + gsize count; + GError *err = NULL; + memset(buf, 0, 1024); + GIOStatus status = g_io_channel_read_chars(channel, buf, 1024, + &count, &err); + if (err != NULL) { + g_warning("error reading channel: %s", err->message); + conn_channel_close(s); + g_error_free(err); + return false; + } + switch (status) { + case G_IO_STATUS_ERROR: + g_warning("problem"); + return false; + case G_IO_STATUS_NORMAL: + g_debug("read data, count: %d, data: %s", (int)count, buf); + json_message_parser_feed(&s->parser, (char *)buf, (int)count); + case G_IO_STATUS_AGAIN: + /* virtio causes us to spin here when no process is attached to + * host-side chardev. sleep a bit to mitigate this + */ + if (s->virtio) { + usleep(100*1000); + } + return true; + case G_IO_STATUS_EOF: + g_debug("received EOF"); + conn_channel_close(s); + if (s->virtio) { + return true; + } + return false; + default: + g_warning("unknown channel read status, closing"); + conn_channel_close(s); + return false; + } + return true; +} + +static int conn_channel_add(GAState *s, int fd) +{ + GIOChannel *conn_channel; + GError *err = NULL; + + g_assert(s && !s->conn_channel); + conn_channel = g_io_channel_unix_new(fd); + g_assert(conn_channel); + g_io_channel_set_encoding(conn_channel, NULL, &err); + if (err != NULL) { + g_warning("error setting channel encoding to binary"); + g_error_free(err); + return -1; + } + g_io_add_watch(conn_channel, G_IO_IN | G_IO_HUP, + conn_channel_read, s); + s->conn_channel = conn_channel; + return 0; +} + +static gboolean listen_channel_accept(GIOChannel *channel, + GIOCondition condition, gpointer data) +{ + GAState *s = data; + GError *err = NULL; + g_assert(channel != NULL); + int ret; + bool accepted = false; + + s->conn_sock = g_socket_accept(s->listen_sock, NULL, &err); + if (err != NULL) { + g_warning("error converting fd to gsocket: %s", err->message); + g_error_free(err); + goto out; + } + ret = conn_channel_add(s, g_socket_get_fd(s->conn_sock)); + if (ret) { + g_warning("error setting up connection"); + goto out; + } + accepted = true; + +out: + /* only accept 1 connection at a time */ + return !accepted; +} + +/* start polling for readable events on listen fd, new==true + * indicates we should use the existing s->listen_channel + */ +static int listen_channel_add(GAState *s, int listen_fd, bool new) +{ + GError *err = NULL; + + if (new) { + s->listen_channel = g_io_channel_unix_new(listen_fd); + if (s->listen_sock) { + g_object_unref(s->listen_sock); + } + s->listen_sock = g_socket_new_from_fd(listen_fd, &err); + if (err != NULL) { + g_warning("error converting fd to gsocket: %s", err->message); + g_error_free(err); + return -1; + } + } + g_io_add_watch(s->listen_channel, G_IO_IN, + listen_channel_accept, s); + return 0; +} + +/* cleanup state for closed connection/session, start accepting new + * connections if we're in listening mode + */ +static void conn_channel_close(GAState *s) +{ + if (strcmp(s->method, "unix-listen") == 0) { + g_io_channel_shutdown(s->conn_channel, true, NULL); + g_object_unref(s->conn_sock); + s->conn_sock = NULL; + listen_channel_add(s, 0, false); + } else if (strcmp(s->method, "virtio-serial") == 0) { + /* we spin on EOF for virtio-serial, so back off a bit. also, + * dont close the connection in this case, it'll resume normal + * operation when another process connects to host chardev + */ + usleep(100*1000); + goto out_noclose; + } + g_io_channel_unref(s->conn_channel); + s->conn_channel = NULL; +out_noclose: + return; +} + +static void init_guest_agent(GAState *s) +{ + struct termios tio; + int ret, fd; + + if (s->method == NULL) { + /* try virtio-serial as our default */ + s->method = "virtio-serial"; + } + + if (s->path == NULL) { + if (strcmp(s->method, "virtio-serial") != 0) { + g_critical("must specify a path for this channel"); + exit(EXIT_FAILURE); + } + /* try the default path for the virtio-serial port */ + s->path = QGA_VIRTIO_PATH_DEFAULT; + } + + if (strcmp(s->method, "virtio-serial") == 0) { + s->virtio = true; + fd = qemu_open(s->path, O_RDWR | O_NONBLOCK | O_ASYNC); + if (fd == -1) { + g_critical("error opening channel: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + ret = conn_channel_add(s, fd); + if (ret) { + g_critical("error adding channel to main loop"); + exit(EXIT_FAILURE); + } + } else if (strcmp(s->method, "isa-serial") == 0) { + fd = qemu_open(s->path, O_RDWR | O_NOCTTY); + if (fd == -1) { + g_critical("error opening channel: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + tcgetattr(fd, &tio); + /* set up serial port for non-canonical, dumb byte streaming */ + tio.c_iflag &= ~(IGNBRK | BRKINT | IGNPAR | PARMRK | INPCK | ISTRIP | + INLCR | IGNCR | ICRNL | IXON | IXOFF | IXANY | + IMAXBEL); + tio.c_oflag = 0; + tio.c_lflag = 0; + tio.c_cflag |= QGA_BAUDRATE_DEFAULT; + /* 1 available byte min or reads will block (we'll set non-blocking + * elsewhere, else we have to deal with read()=0 instead) + */ + tio.c_cc[VMIN] = 1; + tio.c_cc[VTIME] = 0; + /* flush everything waiting for read/xmit, it's garbage at this point */ + tcflush(fd, TCIFLUSH); + tcsetattr(fd, TCSANOW, &tio); + ret = conn_channel_add(s, fd); + if (ret) { + g_error("error adding channel to main loop"); + } + } else if (strcmp(s->method, "unix-listen") == 0) { + fd = unix_listen(s->path, NULL, strlen(s->path)); + if (fd == -1) { + g_critical("error opening path: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + ret = listen_channel_add(s, fd, true); + if (ret) { + g_critical("error binding/listening to specified socket"); + exit(EXIT_FAILURE); + } + } else { + g_critical("unsupported channel method/type: %s", s->method); + exit(EXIT_FAILURE); + } + + json_message_parser_init(&s->parser, process_event); + s->main_loop = g_main_loop_new(NULL, false); +} + +int main(int argc, char **argv) +{ + const char *sopt = "hVvdm:p:l:f:"; + const char *method = NULL, *path = NULL, *pidfile = QGA_PIDFILE_DEFAULT; + const struct option lopt[] = { + { "help", 0, NULL, 'h' }, + { "version", 0, NULL, 'V' }, + { "logfile", 0, NULL, 'l' }, + { "pidfile", 0, NULL, 'f' }, + { "verbose", 0, NULL, 'v' }, + { "method", 0, NULL, 'm' }, + { "path", 0, NULL, 'p' }, + { "daemonize", 0, NULL, 'd' }, + { NULL, 0, NULL, 0 } + }; + int opt_ind = 0, ch, daemonize = 0; + GLogLevelFlags log_level = G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL; + FILE *log_file = stderr; + GAState *s; + + while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { + switch (ch) { + case 'm': + method = optarg; + break; + case 'p': + path = optarg; + break; + case 'l': + log_file = fopen(optarg, "a"); + if (!log_file) { + g_critical("unable to open specified log file: %s", + strerror(errno)); + return EXIT_FAILURE; + } + break; + case 'f': + pidfile = optarg; + break; + case 'v': + /* enable all log levels */ + log_level = G_LOG_LEVEL_MASK; + break; + case 'V': + printf("QEMU Guest Agent %s\n", QGA_VERSION); + return 0; + case 'd': + daemonize = 1; + break; + case 'h': + usage(argv[0]); + return 0; + case '?': + g_print("Unknown option, try '%s --help' for more information.\n", + argv[0]); + return EXIT_FAILURE; + } + } + + if (daemonize) { + g_debug("starting daemon"); + become_daemon(pidfile); + } + + g_type_init(); + g_thread_init(NULL); + + s = qemu_mallocz(sizeof(GAState)); + s->conn_channel = NULL; + s->path = path; + s->method = method; + s->log_file = log_file; + s->log_level = log_level; + g_log_set_default_handler(ga_log, s); + g_log_set_fatal_mask(NULL, G_LOG_LEVEL_ERROR); + s->logging_enabled = true; + ga_state = s; + + module_call_init(MODULE_INIT_QAPI); + init_guest_agent(ga_state); + register_signal_handlers(); + + g_main_loop_run(ga_state->main_loop); + + unlink(pidfile); + + return 0; +} |