From 3f2546b2ef55b661fd8dd69682b38992225e86f6 Mon Sep 17 00:00:00 2001 From: fishsoupisgood Date: Mon, 29 Apr 2019 01:17:54 +0100 Subject: Initial import of qemu-2.4.1 --- os-posix.c | 336 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 336 insertions(+) create mode 100644 os-posix.c (limited to 'os-posix.c') diff --git a/os-posix.c b/os-posix.c new file mode 100644 index 00000000..e4da406f --- /dev/null +++ b/os-posix.c @@ -0,0 +1,336 @@ +/* + * os-posix.c + * + * Copyright (c) 2003-2008 Fabrice Bellard + * Copyright (c) 2010 Red Hat, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include +#include +#include +#include +#include +/*needed for MAP_POPULATE before including qemu-options.h */ +#include +#include +#include +#include + +/* Needed early for CONFIG_BSD etc. */ +#include "config-host.h" +#include "sysemu/sysemu.h" +#include "net/slirp.h" +#include "qemu-options.h" +#include "qemu/rcu.h" + +#ifdef CONFIG_LINUX +#include +#endif + +static struct passwd *user_pwd; +static const char *chroot_dir; +static int daemonize; +static int daemon_pipe; + +void os_setup_early_signal_handling(void) +{ + struct sigaction act; + sigfillset(&act.sa_mask); + act.sa_flags = 0; + act.sa_handler = SIG_IGN; + sigaction(SIGPIPE, &act, NULL); +} + +static void termsig_handler(int signal, siginfo_t *info, void *c) +{ + qemu_system_killed(info->si_signo, info->si_pid); +} + +void os_setup_signal_handling(void) +{ + struct sigaction act; + + memset(&act, 0, sizeof(act)); + act.sa_sigaction = termsig_handler; + act.sa_flags = SA_SIGINFO; + sigaction(SIGINT, &act, NULL); + sigaction(SIGHUP, &act, NULL); + sigaction(SIGTERM, &act, NULL); +} + +/* Find a likely location for support files using the location of the binary. + For installed binaries this will be "$bindir/../share/qemu". When + running from the build tree this will be "$bindir/../pc-bios". */ +#define SHARE_SUFFIX "/share/qemu" +#define BUILD_SUFFIX "/pc-bios" +char *os_find_datadir(void) +{ + char *dir, *exec_dir; + char *res; + size_t max_len; + + exec_dir = qemu_get_exec_dir(); + if (exec_dir == NULL) { + return NULL; + } + dir = dirname(exec_dir); + + max_len = strlen(dir) + + MAX(strlen(SHARE_SUFFIX), strlen(BUILD_SUFFIX)) + 1; + res = g_malloc0(max_len); + snprintf(res, max_len, "%s%s", dir, SHARE_SUFFIX); + if (access(res, R_OK)) { + snprintf(res, max_len, "%s%s", dir, BUILD_SUFFIX); + if (access(res, R_OK)) { + g_free(res); + res = NULL; + } + } + + g_free(exec_dir); + return res; +} +#undef SHARE_SUFFIX +#undef BUILD_SUFFIX + +void os_set_proc_name(const char *s) +{ +#if defined(PR_SET_NAME) + char name[16]; + if (!s) + return; + pstrcpy(name, sizeof(name), s); + /* Could rewrite argv[0] too, but that's a bit more complicated. + This simple way is enough for `top'. */ + if (prctl(PR_SET_NAME, name)) { + perror("unable to change process name"); + exit(1); + } +#else + fprintf(stderr, "Change of process name not supported by your OS\n"); + exit(1); +#endif +} + +/* + * Parse OS specific command line options. + * return 0 if option handled, -1 otherwise + */ +void os_parse_cmd_args(int index, const char *optarg) +{ + switch (index) { +#ifdef CONFIG_SLIRP + case QEMU_OPTION_smb: + if (net_slirp_smb(optarg) < 0) + exit(1); + break; +#endif + case QEMU_OPTION_runas: + user_pwd = getpwnam(optarg); + if (!user_pwd) { + fprintf(stderr, "User \"%s\" doesn't exist\n", optarg); + exit(1); + } + break; + case QEMU_OPTION_chroot: + chroot_dir = optarg; + break; + case QEMU_OPTION_daemonize: + daemonize = 1; + break; +#if defined(CONFIG_LINUX) + case QEMU_OPTION_enablefips: + fips_set_state(true); + break; +#endif + } +} + +static void change_process_uid(void) +{ + if (user_pwd) { + if (setgid(user_pwd->pw_gid) < 0) { + fprintf(stderr, "Failed to setgid(%d)\n", user_pwd->pw_gid); + exit(1); + } + if (initgroups(user_pwd->pw_name, user_pwd->pw_gid) < 0) { + fprintf(stderr, "Failed to initgroups(\"%s\", %d)\n", + user_pwd->pw_name, user_pwd->pw_gid); + exit(1); + } + if (setuid(user_pwd->pw_uid) < 0) { + fprintf(stderr, "Failed to setuid(%d)\n", user_pwd->pw_uid); + exit(1); + } + if (setuid(0) != -1) { + fprintf(stderr, "Dropping privileges failed\n"); + exit(1); + } + } +} + +static void change_root(void) +{ + if (chroot_dir) { + if (chroot(chroot_dir) < 0) { + fprintf(stderr, "chroot failed\n"); + exit(1); + } + if (chdir("/")) { + perror("not able to chdir to /"); + exit(1); + } + } + +} + +void os_daemonize(void) +{ + if (daemonize) { + pid_t pid; + int fds[2]; + + if (pipe(fds) == -1) { + exit(1); + } + + pid = fork(); + if (pid > 0) { + uint8_t status; + ssize_t len; + + close(fds[1]); + + do { + len = read(fds[0], &status, 1); + } while (len < 0 && errno == EINTR); + + /* only exit successfully if our child actually wrote + * a one-byte zero to our pipe, upon successful init */ + exit(len == 1 && status == 0 ? 0 : 1); + + } else if (pid < 0) { + exit(1); + } + + close(fds[0]); + daemon_pipe = fds[1]; + qemu_set_cloexec(daemon_pipe); + + setsid(); + + pid = fork(); + if (pid > 0) { + exit(0); + } else if (pid < 0) { + exit(1); + } + umask(027); + + signal(SIGTSTP, SIG_IGN); + signal(SIGTTOU, SIG_IGN); + signal(SIGTTIN, SIG_IGN); + rcu_after_fork(); + } +} + +void os_setup_post(void) +{ + int fd = 0; + + if (daemonize) { + if (chdir("/")) { + perror("not able to chdir to /"); + exit(1); + } + TFR(fd = qemu_open("/dev/null", O_RDWR)); + if (fd == -1) { + exit(1); + } + } + + change_root(); + change_process_uid(); + + if (daemonize) { + uint8_t status = 0; + ssize_t len; + + dup2(fd, 0); + dup2(fd, 1); + dup2(fd, 2); + + close(fd); + + do { + len = write(daemon_pipe, &status, 1); + } while (len < 0 && errno == EINTR); + if (len != 1) { + exit(1); + } + } +} + +void os_set_line_buffering(void) +{ + setvbuf(stdout, NULL, _IOLBF, 0); +} + +int qemu_create_pidfile(const char *filename) +{ + char buffer[128]; + int len; + int fd; + + fd = qemu_open(filename, O_RDWR | O_CREAT, 0600); + if (fd == -1) { + return -1; + } + if (lockf(fd, F_TLOCK, 0) == -1) { + close(fd); + return -1; + } + len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", getpid()); + if (write(fd, buffer, len) != len) { + close(fd); + return -1; + } + + /* keep pidfile open & locked forever */ + return 0; +} + +bool is_daemonized(void) +{ + return daemonize; +} + +int os_mlock(void) +{ + int ret = 0; + + ret = mlockall(MCL_CURRENT | MCL_FUTURE); + if (ret < 0) { + perror("mlockall"); + } + + return ret; +} -- cgit v1.2.3