/* Miscellaneous system calls. Author: Kees J. Bot * 31 Mar 2000 * The entry points into this file are: * do_reboot: kill all processes, then reboot system * do_getsysinfo: request copy of PM data structure (Jorrit N. Herder) * do_getprocnr: lookup endpoint by process ID * do_getepinfo: get the pid/uid/gid of a process given its endpoint * do_getsetpriority: get/set process priority * do_svrctl: process manager control */ #include "pm.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "mproc.h" #include "kernel/proc.h" struct utsname uts_val = { OS_NAME, /* system name */ "noname", /* node/network name */ OS_RELEASE, /* O.S. release (e.g. 3.3.0) */ OS_VERSION, /* O.S. version (e.g. Minix 3.3.0 (GENERIC)) */ "xyzzy", /* machine (cpu) type (filled in later) */ #if defined(__i386__) "i386", /* architecture */ #elif defined(__arm__) "arm", /* architecture */ #else #error /* oops, no 'uname -mk' */ #endif }; static char *uts_tbl[] = { uts_val.arch, NULL, /* No kernel architecture */ uts_val.machine, NULL, /* No hostname */ uts_val.nodename, uts_val.release, uts_val.version, uts_val.sysname, NULL, /* No bus */ /* No bus */ }; #if ENABLE_SYSCALL_STATS unsigned long calls_stats[NR_PM_CALLS]; #endif /*===========================================================================* * do_sysuname * *===========================================================================*/ int do_sysuname() { /* Set or get uname strings. */ int r; size_t n; char *string; #if 0 /* for updates */ char tmp[sizeof(uts_val.nodename)]; static short sizes[] = { 0, /* arch, (0 = read-only) */ 0, /* kernel */ 0, /* machine */ 0, /* sizeof(uts_val.hostname), */ sizeof(uts_val.nodename), 0, /* release */ 0, /* version */ 0, /* sysname */ }; #endif if (m_in.m_lc_pm_sysuname.field >= _UTS_MAX) return(EINVAL); string = uts_tbl[m_in.m_lc_pm_sysuname.field]; if (string == NULL) return EINVAL; /* Unsupported field */ switch (m_in.m_lc_pm_sysuname.req) { case _UTS_GET: /* Copy an uname string to the user. */ n = strlen(string) + 1; if (n > m_in.m_lc_pm_sysuname.len) n = m_in.m_lc_pm_sysuname.len; r = sys_datacopy(SELF, (vir_bytes)string, mp->mp_endpoint, m_in.m_lc_pm_sysuname.value, (phys_bytes)n); if (r < 0) return(r); break; #if 0 /* no updates yet */ case _UTS_SET: /* Set an uname string, needs root power. */ len = sizes[m_in.m_lc_pm_sysuname.field]; if (mp->mp_effuid != 0 || len == 0) return(EPERM); n = len < m_in.m_lc_pm_sysuname.len ? len : m_in.m_lc_pm_sysuname.len; if (n <= 0) return(EINVAL); r = sys_datacopy(mp->mp_endpoint, m_in.m_lc_pm_sysuname.value, SELF, (phys_bytes)tmp, (phys_bytes)n); if (r < 0) return(r); tmp[n-1] = 0; strcpy(string, tmp); break; #endif default: return(EINVAL); } /* Return the number of bytes moved. */ return(n); } /*===========================================================================* * do_getsysinfo * *===========================================================================*/ int do_getsysinfo() { vir_bytes src_addr, dst_addr; size_t len; /* This call leaks important information. In the future, requests from * non-system processes should be denied. */ if (mp->mp_effuid != 0) { printf("PM: unauthorized call of do_getsysinfo by proc %d '%s'\n", mp->mp_endpoint, mp->mp_name); sys_diagctl_stacktrace(mp->mp_endpoint); return EPERM; } switch(m_in.SI_WHAT) { case SI_PROC_TAB: /* copy entire process table */ src_addr = (vir_bytes) mproc; len = sizeof(struct mproc) * NR_PROCS; break; #if ENABLE_SYSCALL_STATS case SI_CALL_STATS: src_addr = (vir_bytes) calls_stats; len = sizeof(calls_stats); break; #endif default: return(EINVAL); } if (len != m_in.SI_SIZE) return(EINVAL); dst_addr = (vir_bytes) m_in.SI_WHERE; return sys_datacopy(SELF, src_addr, who_e, dst_addr, len); } /*===========================================================================* * do_getprocnr * *===========================================================================*/ int do_getprocnr(void) { register struct mproc *rmp; /* This check should be replaced by per-call ACL checks. */ if (who_e != RS_PROC_NR) { printf("PM: unauthorized call of do_getprocnr by %d\n", who_e); return EPERM; } if ((rmp = find_proc(m_in.m_lsys_pm_getprocnr.pid)) == NULL) return(ESRCH); mp->mp_reply.m_pm_lsys_getprocnr.endpt = rmp->mp_endpoint; return(OK); } /*===========================================================================* * do_getepinfo * *===========================================================================*/ int do_getepinfo(void) { struct mproc *rmp; endpoint_t ep; int slot; ep = m_in.m_lsys_pm_getepinfo.endpt; if (pm_isokendpt(ep, &slot) != OK) return(ESRCH); rmp = &mproc[slot]; mp->mp_reply.m_pm_lsys_getepinfo.uid = rmp->mp_effuid; mp->mp_reply.m_pm_lsys_getepinfo.gid = rmp->mp_effgid; return(rmp->mp_pid); } /*===========================================================================* * do_reboot * *===========================================================================*/ int do_reboot() { message m; /* Check permission to abort the system. */ if (mp->mp_effuid != SUPER_USER) return(EPERM); /* See how the system should be aborted. */ abort_flag = (unsigned) m_in.PM_REBOOT_HOW; /* notify readclock (some arm systems power off via RTC alarms) */ if (abort_flag & RB_POWERDOWN) { endpoint_t readclock_ep; if (ds_retrieve_label_endpt("readclock.drv", &readclock_ep) == OK) { message m; /* no params to set, nothing we can do if it fails */ _taskcall(readclock_ep, RTCDEV_PWR_OFF, &m); } } /* Order matters here. When VFS is told to reboot, it exits all its * processes, and then would be confused if they're exited again by * SIGKILL. So first kill, then reboot. */ check_sig(-1, SIGKILL, FALSE /* ksig*/); /* kill all users except init */ sys_stop(INIT_PROC_NR); /* stop init, but keep it around */ /* Tell VFS to reboot */ memset(&m, 0, sizeof(m)); m.m_type = VFS_PM_REBOOT; tell_vfs(&mproc[VFS_PROC_NR], &m); return(SUSPEND); /* don't reply to caller */ } /*===========================================================================* * do_getsetpriority * *===========================================================================*/ int do_getsetpriority() { int r, arg_which, arg_who, arg_pri; struct mproc *rmp; arg_which = m_in.m_lc_pm_priority.which; arg_who = m_in.m_lc_pm_priority.who; arg_pri = m_in.m_lc_pm_priority.prio; /* for SETPRIORITY */ /* Code common to GETPRIORITY and SETPRIORITY. */ /* Only support PRIO_PROCESS for now. */ if (arg_which != PRIO_PROCESS) return(EINVAL); if (arg_who == 0) rmp = mp; else if ((rmp = find_proc(arg_who)) == NULL) return(ESRCH); if (mp->mp_effuid != SUPER_USER && mp->mp_effuid != rmp->mp_effuid && mp->mp_effuid != rmp->mp_realuid) return EPERM; /* If GET, that's it. */ if (call_nr == PM_GETPRIORITY) { return(rmp->mp_nice - PRIO_MIN); } /* Only root is allowed to reduce the nice level. */ if (rmp->mp_nice > arg_pri && mp->mp_effuid != SUPER_USER) return(EACCES); /* We're SET, and it's allowed. * * The value passed in is currently between PRIO_MIN and PRIO_MAX. * We have to scale this between MIN_USER_Q and MAX_USER_Q to match * the kernel's scheduling queues. */ if ((r = sched_nice(rmp, arg_pri)) != OK) { return r; } rmp->mp_nice = arg_pri; return(OK); } /*===========================================================================* * do_svrctl * *===========================================================================*/ int do_svrctl() { int s, req; vir_bytes ptr; #define MAX_LOCAL_PARAMS 2 static struct { char name[30]; char value[30]; } local_param_overrides[MAX_LOCAL_PARAMS]; static int local_params = 0; req = m_in.SVRCTL_REQ; ptr = (vir_bytes) m_in.SVRCTL_ARG; /* Is the request indeed for the PM? */ if (((req >> 8) & 0xFF) != 'M') return(EINVAL); /* Control operations local to the PM. */ switch(req) { case PMSETPARAM: case PMGETPARAM: { struct sysgetenv sysgetenv; char search_key[64]; char *val_start; size_t val_len; size_t copy_len; /* Copy sysgetenv structure to PM. */ if (sys_datacopy(who_e, ptr, SELF, (vir_bytes) &sysgetenv, sizeof(sysgetenv)) != OK) return(EFAULT); /* Set a param override? */ if (req == PMSETPARAM) { if (local_params >= MAX_LOCAL_PARAMS) return ENOSPC; if (sysgetenv.keylen <= 0 || sysgetenv.keylen >= sizeof(local_param_overrides[local_params].name) || sysgetenv.vallen <= 0 || sysgetenv.vallen >= sizeof(local_param_overrides[local_params].value)) return EINVAL; if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.key, SELF, (vir_bytes) local_param_overrides[local_params].name, sysgetenv.keylen)) != OK) return s; if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.val, SELF, (vir_bytes) local_param_overrides[local_params].value, sysgetenv.vallen)) != OK) return s; local_param_overrides[local_params].name[sysgetenv.keylen] = '\0'; local_param_overrides[local_params].value[sysgetenv.vallen] = '\0'; local_params++; return OK; } if (sysgetenv.keylen == 0) { /* copy all parameters */ val_start = monitor_params; val_len = sizeof(monitor_params); } else { /* lookup value for key */ int p; /* Try to get a copy of the requested key. */ if (sysgetenv.keylen > sizeof(search_key)) return(EINVAL); if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.key, SELF, (vir_bytes) search_key, sysgetenv.keylen)) != OK) return(s); /* Make sure key is null-terminated and lookup value. * First check local overrides. */ search_key[sysgetenv.keylen-1]= '\0'; for(p = 0; p < local_params; p++) { if (!strcmp(search_key, local_param_overrides[p].name)) { val_start = local_param_overrides[p].value; break; } } if (p >= local_params && (val_start = find_param(search_key)) == NULL) return(ESRCH); val_len = strlen(val_start) + 1; } /* See if it fits in the client's buffer. */ if (val_len > sysgetenv.vallen) return E2BIG; /* Value found, make the actual copy (as far as possible). */ copy_len = MIN(val_len, sysgetenv.vallen); if ((s=sys_datacopy(SELF, (vir_bytes) val_start, who_e, (vir_bytes) sysgetenv.val, copy_len)) != OK) return(s); return OK; } default: return(EINVAL); } } /*===========================================================================* * do_getrusage * *===========================================================================*/ int do_getrusage() { int res = 0; clock_t user_time = 0; clock_t sys_time = 0; struct rusage r_usage; u64_t usec; if (m_in.RU_WHO != RUSAGE_SELF && m_in.RU_WHO != RUSAGE_CHILDREN) return EINVAL; if ((res = sys_getrusage(&r_usage, who_e)) < 0) return res; if (m_in.RU_WHO == RUSAGE_CHILDREN) { usec = mp->mp_child_utime * 1000000 / sys_hz(); r_usage.ru_utime.tv_sec = usec / 1000000; r_usage.ru_utime.tv_usec = usec % 1000000; usec = mp->mp_child_stime * 1000000 / sys_hz(); r_usage.ru_stime.tv_sec = usec / 1000000; r_usage.ru_stime.tv_usec = usec % 1000000; } return sys_datacopy(SELF, (vir_bytes) &r_usage, who_e, (vir_bytes) m_in.RU_RUSAGE_ADDR, (vir_bytes) sizeof(r_usage)); }