X-Git-Url: http://mj.ucw.cz/gitweb/?a=blobdiff_plain;ds=inline;f=box%2Fbox.c;h=ca2a292bbb3d2793e965b0ae1b5ea307e432c575;hb=def7011b3ec2f20cc195a4405198e03eb6c92b47;hp=c1dcabf34c39c7b295645df3a924f6caaa5bfb79;hpb=516819da6fc061e418aabbac588014d3c649ac5e;p=moe.git diff --git a/box/box.c b/box/box.c index c1dcabf..ca2a292 100644 --- a/box/box.c +++ b/box/box.c @@ -47,7 +47,11 @@ static int ticks_per_sec; static int exec_seen; static int partial_line; +static int mem_peak_kb; +static int total_ms, wall_ms; + static void die(char *msg, ...) NONRET; +static void sample_mem_peak(void); /*** Meta-files ***/ @@ -85,8 +89,6 @@ meta_printf(const char *fmt, ...) va_end(args); } -static int total_ms, wall_ms; - static void final_stats(struct rusage *rus) { @@ -94,12 +96,12 @@ final_stats(struct rusage *rus) timeradd(&rus->ru_utime, &rus->ru_stime, &total); total_ms = total.tv_sec*1000 + total.tv_usec/1000; gettimeofday(&now, NULL); - // FIXME: We are not guaranteed to have start_time always initialized timersub(&now, &start_time, &wall); wall_ms = wall.tv_sec*1000 + wall.tv_usec/1000; meta_printf("time:%d.%03d\n", total_ms/1000, total_ms%1000); meta_printf("time-wall:%d.%03d\n", wall_ms/1000, wall_ms%1000); + meta_printf("mem:%llu\n", (unsigned long long) mem_peak_kb * 1024); } /*** Messages and exits ***/ @@ -109,6 +111,7 @@ box_exit(int rc) { if (box_pid > 0) { + sample_mem_peak(); if (is_ptraced) ptrace(PTRACE_KILL, box_pid); kill(-box_pid, SIGKILL); @@ -134,28 +137,42 @@ flush_line(void) partial_line = 0; } +/* Report an error of the sandbox itself */ static void NONRET __attribute__((format(printf,1,2))) die(char *msg, ...) { va_list args; va_start(args, msg); flush_line(); - vfprintf(stderr, msg, args); + char buf[1024]; + vsnprintf(buf, sizeof(buf), msg, args); + meta_printf("status:XX\nmessage:%s\n", buf); + fputs(buf, stderr); fputc('\n', stderr); box_exit(2); } +/* Report an error of the program inside the sandbox */ static void NONRET __attribute__((format(printf,1,2))) err(char *msg, ...) { va_list args; va_start(args, msg); flush_line(); - vfprintf(stderr, msg, args); + if (msg[0] && msg[1] && msg[2] == ':' && msg[3] == ' ') + { + meta_printf("status:%c%c\n", msg[0], msg[1]); + msg += 4; + } + char buf[1024]; + vsnprintf(buf, sizeof(buf), msg, args); + meta_printf("message:%s\n", buf); + fputs(buf, stderr); fputc('\n', stderr); box_exit(1); } +/* Write a message, but only if in verbose mode */ static void __attribute__((format(printf,1,2))) msg(char *msg, ...) { @@ -194,7 +211,10 @@ enum action { A_NO, // Always forbid A_YES, // Always permit A_FILENAME, // Permit if arg1 is a known filename + A_ACTION_MASK = 15, + A_SAMPLE_MEM = 64, // Sample memory usage before the syscall A_LIBERAL = 128, // Valid only in liberal mode + // Must fit in a unsigned char }; static unsigned char syscall_action[NUM_ACTIONS] = { @@ -216,7 +236,7 @@ static unsigned char syscall_action[NUM_ACTIONS] = { S(readlink) = A_FILENAME, // Syscalls permitted always - S(exit) = A_YES, + S(exit) = A_YES | A_SAMPLE_MEM, S(read) = A_YES, S(write) = A_YES, S(close) = A_YES, @@ -249,13 +269,15 @@ static unsigned char syscall_action[NUM_ACTIONS] = { S(fcntl) = A_YES, S(fcntl64) = A_YES, S(mmap) = A_YES, + S(mmap2) = A_YES, S(munmap) = A_YES, S(ioctl) = A_YES, S(uname) = A_YES, S(gettid) = A_YES, S(set_thread_area) = A_YES, S(get_thread_area) = A_YES, - S(exit_group) = A_YES, + S(set_tid_address) = A_YES, + S(exit_group) = A_YES | A_SAMPLE_MEM, // Syscalls permitted only in liberal mode S(time) = A_YES | A_LIBERAL, @@ -294,7 +316,6 @@ static unsigned char syscall_action[NUM_ACTIONS] = { S(rt_sigtimedwait) = A_YES | A_LIBERAL, S(rt_sigqueueinfo) = A_YES | A_LIBERAL, S(rt_sigsuspend) = A_YES | A_LIBERAL, - S(mmap2) = A_YES | A_LIBERAL, S(_sysctl) = A_YES | A_LIBERAL, #undef S }; @@ -568,7 +589,7 @@ valid_filename(unsigned long addr) static int mem_fd; if (!file_access) - err("File access forbidden"); + err("FA: File access forbidden"); if (file_access >= 9) return; @@ -589,14 +610,14 @@ valid_filename(unsigned long addr) if (l > remains) l = remains; if (!l) - err("Access to file with name too long"); + err("FA: Access to file with name too long"); if (lseek64(mem_fd, addr, SEEK_SET) < 0) die("lseek64(mem): %m"); remains = read(mem_fd, end, l); if (remains < 0) die("read(mem): %m"); if (!remains) - err("Access to file with name out of memory"); + err("FA: Access to file with name out of memory"); end += l; addr += l; } @@ -626,31 +647,31 @@ valid_filename(unsigned long addr) act = match_path_rule(&default_path_rules[i], namebuf); if (act != A_YES) - err("Forbidden access to file `%s'", namebuf); + err("FA: Forbidden access to file `%s'", namebuf); } +// Check syscall. If invalid, return -1, otherwise return the action mask. static int valid_syscall(struct user *u) { unsigned int sys = u->regs.orig_eax; - enum action act = (sys < NUM_ACTIONS) ? syscall_action[sys] : A_DEFAULT; + unsigned int act = (sys < NUM_ACTIONS) ? syscall_action[sys] : A_DEFAULT; if (act & A_LIBERAL) { - if (filter_syscalls == 1) - act &= ~A_LIBERAL; - else + if (filter_syscalls != 1) act = A_DEFAULT; } - switch (act) + + switch (act & A_ACTION_MASK) { case A_YES: - return 1; + return act; case A_NO: - return 0; + return -1; case A_FILENAME: valid_filename(u->regs.ebx); - return 1; + return act; default: ; } @@ -658,14 +679,20 @@ valid_syscall(struct user *u) { case __NR_kill: if (u->regs.ebx == box_pid) - err("Committed suicide by signal %d", (int)u->regs.ecx); - return 0; + { + meta_printf("exitsig:%d\n", (int)u->regs.ecx); + err("SG: Committed suicide by signal %d", (int)u->regs.ecx); + } + return -1; case __NR_tgkill: if (u->regs.ebx == box_pid && u->regs.ecx == box_pid) - err("Committed suicide by signal %d", (int)u->regs.edx); - return 0; + { + meta_printf("exitsig:%d\n", (int)u->regs.edx); + err("SG: Committed suicide by signal %d", (int)u->regs.edx); + } + return -1; default: - return 0; + return -1; } } @@ -681,7 +708,29 @@ static void signal_int(int unused UNUSED) { /* Interrupts are fatal, so no synchronization requirements. */ - err("Interrupted"); + meta_printf("exitsig:%d\n", SIGINT); + err("SG: Interrupted"); +} + +#define PROC_BUF_SIZE 4096 +static void +read_proc_file(char *buf, char *name, int *fdp) +{ + int c; + + if (!*fdp) + { + sprintf(buf, "/proc/%d/%s", (int) box_pid, name); + *fdp = open(buf, O_RDONLY); + if (*fdp < 0) + die("open(%s): %m", buf); + } + lseek(*fdp, 0, SEEK_SET); + if ((c = read(*fdp, buf, PROC_BUF_SIZE-1)) < 0) + die("read on /proc/$pid/%s: %m", name); + if (c >= PROC_BUF_SIZE-1) + die("/proc/$pid/%s too long", name); + buf[c] = 0; } static void @@ -695,47 +744,80 @@ check_timeout(void) timersub(&now, &start_time, &wall); wall_ms = wall.tv_sec*1000 + wall.tv_usec/1000; if (wall_ms > wall_timeout) - err("Time limit exceeded (wall clock)"); + err("TO: Time limit exceeded (wall clock)"); if (verbose > 1) fprintf(stderr, "[wall time check: %d msec]\n", wall_ms); } if (timeout) { - char buf[4096], *x; - int c, utime, stime, ms; - static int proc_status_fd; - if (!proc_status_fd) - { - sprintf(buf, "/proc/%d/stat", (int) box_pid); - proc_status_fd = open(buf, O_RDONLY); - if (proc_status_fd < 0) - die("open(%s): %m", buf); - } - lseek(proc_status_fd, 0, SEEK_SET); - if ((c = read(proc_status_fd, buf, sizeof(buf)-1)) < 0) - die("read on /proc/$pid/stat: %m"); - if (c >= (int) sizeof(buf) - 1) - die("/proc/$pid/stat too long"); - buf[c] = 0; + char buf[PROC_BUF_SIZE], *x; + int utime, stime, ms; + static int proc_stat_fd; + read_proc_file(buf, "stat", &proc_stat_fd); x = buf; while (*x && *x != ' ') x++; while (*x == ' ') x++; if (*x++ != '(') - die("proc syntax error 1"); + die("proc stat syntax error 1"); while (*x && (*x != ')' || x[1] != ' ')) x++; while (*x == ')' || *x == ' ') x++; if (sscanf(x, "%*c %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %d %d", &utime, &stime) != 2) - die("proc syntax error 2"); + die("proc stat syntax error 2"); ms = (utime + stime) * 1000 / ticks_per_sec; if (verbose > 1) fprintf(stderr, "[time check: %d msec]\n", ms); if (ms > timeout) - err("Time limit exceeded"); + err("TO: Time limit exceeded"); + } +} + +static void +sample_mem_peak(void) +{ + /* + * We want to find out the peak memory usage of the process, which is + * maintained by the kernel, but unforunately it gets lost when the + * process exits (it is not reported in struct rusage). Therefore we + * have to sample it whenever we suspect that the process is about + * to exit. + */ + char buf[PROC_BUF_SIZE], *x; + static int proc_status_fd; + read_proc_file(buf, "status", &proc_status_fd); + + x = buf; + while (*x) + { + char *key = x; + while (*x && *x != ':' && *x != '\n') + x++; + if (!*x || *x == '\n') + break; + *x++ = 0; + while (*x == ' ' || *x == '\t') + x++; + + char *val = x; + while (*x && *x != '\n') + x++; + if (!*x) + break; + *x++ = 0; + + if (!strcmp(key, "VmPeak")) + { + int peak = atoi(val); + if (peak > mem_peak_kb) + mem_peak_kb = peak; + } } + + if (verbose > 1) + msg("[mem-peak: %u KB]\n", mem_peak_kb); } static void @@ -781,24 +863,37 @@ boxkeeper(void) { box_pid = 0; final_stats(&rus); - // FIXME: If the process has exited before being ptraced, signal an internal error if (WEXITSTATUS(stat)) - err("Exited with error status %d", WEXITSTATUS(stat)); + { + if (syscall_count) + { + meta_printf("exitcode:%d\n", WEXITSTATUS(stat)); + err("RE: Exited with error status %d", WEXITSTATUS(stat)); + } + else + { + // Internal error happened inside the child process and it has been already reported. + box_exit(2); + } + } if (timeout && total_ms > timeout) - err("Time limit exceeded"); + err("TO: Time limit exceeded"); if (wall_timeout && wall_ms > wall_timeout) - err("Time limit exceeded (wall clock)"); + err("TO: Time limit exceeded (wall clock)"); flush_line(); - fprintf(stderr, "OK (%d.%03d sec real, %d.%03d sec wall, %d syscalls)\n", + fprintf(stderr, "OK (%d.%03d sec real, %d.%03d sec wall, %d MB, %d syscalls)\n", total_ms/1000, total_ms%1000, wall_ms/1000, wall_ms%1000, + (mem_peak_kb + 1023) / 1024, syscall_count); box_exit(0); } if (WIFSIGNALED(stat)) { box_pid = 0; - err("Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup")); + meta_printf("exitsig:%d\n", WTERMSIG(stat)); + final_stats(&rus); + err("SG: Caught fatal signal %d%s", WTERMSIG(stat), (syscall_count ? "" : " during startup")); } if (WIFSTOPPED(stat)) { @@ -809,12 +904,15 @@ boxkeeper(void) static int stop_count = -1; if (ptrace(PTRACE_GETREGS, box_pid, NULL, &u) < 0) die("ptrace(PTRACE_GETREGS): %m"); + if (u.regs.orig_eax < 0) /* Process issued a breakpoint instruction */ + err("SG: Breakpoint"); stop_count++; if (!stop_count) /* Traceme request */ msg(">> Traceme request caught\n"); else if (stop_count & 1) /* Syscall entry */ { char namebuf[32]; + int act; msg(">> Syscall %-12s (%08lx,%08lx,%08lx) ", syscall_name(u.regs.orig_eax, namebuf), u.regs.ebx, u.regs.ecx, u.regs.edx); if (!exec_seen) { @@ -822,8 +920,12 @@ boxkeeper(void) if (u.regs.orig_eax == __NR_execve) exec_seen = 1; } - else if (valid_syscall(&u)) - syscall_count++; + else if ((act = valid_syscall(&u)) >= 0) + { + syscall_count++; + if (act & A_SAMPLE_MEM) + sample_mem_peak(); + } else { /* @@ -835,7 +937,7 @@ boxkeeper(void) u.regs.orig_eax = 0xffffffff; if (ptrace(PTRACE_SETREGS, box_pid, NULL, &u) < 0) die("ptrace(PTRACE_SETREGS): %m"); - err("Forbidden syscall %s", syscall_name(sys, namebuf)); + err("FO: Forbidden syscall %s", syscall_name(sys, namebuf)); } } else /* Syscall return */ @@ -845,10 +947,14 @@ boxkeeper(void) else if (sig != SIGSTOP && sig != SIGXCPU && sig != SIGXFSZ) { msg(">> Signal %d\n", sig); + sample_mem_peak(); /* Signal might be fatal, so update mem-peak */ ptrace(PTRACE_SYSCALL, box_pid, 0, sig); } else - err("Received signal %d", sig); + { + meta_printf("exitsig:%d", sig); + err("SG: Received signal %d", sig); + } } else die("wait4: unknown status %x, giving up!", stat);