ptracesandbox.c
上传用户:ig0539
上传日期:2022-05-21
资源大小:181k
文件大小:32k
- /*
- * Part of Very Secure FTPd
- * Licence: GPL v2
- * Author: Chris Evans
- * ptracesandbox.c
- *
- * Generic routines to setup and run a process under a restrictive ptrace()
- * based sandbox.
- * Note that the style in this file is to not go via the helper functions in
- * sysutil.c, but instead hit the system APIs directly. This is because I may
- * very well release just this file to the public domain, and do not want
- * dependencies on other parts of vsftpd.
- */
- #include "ptracesandbox.h"
- #if defined(__linux__) && defined(__i386__)
- #include <sys/mman.h>
- #include <sys/prctl.h>
- #include <sys/ptrace.h>
- /* For AF_MAX (NPROTO is defined to this) */
- #include <sys/socket.h>
- #include <sys/types.h>
- #include <sys/user.h>
- #include <sys/wait.h>
- #include <err.h>
- #include <errno.h>
- #include <fcntl.h>
- #include <signal.h>
- #include <stdlib.h>
- #include <string.h>
- #include <unistd.h>
- #include <syslog.h>
- #include <asm/unistd.h>
- #ifndef __NR_sendfile64
- #define __NR_sendfile64 239
- #endif
- #ifndef __NR_exit_group
- #define __NR_exit_group 252
- #endif
- #ifndef __NR_utimes
- #define __NR_utimes 271
- #endif
- /* For the socketcall() multiplex args. */
- #include <linux/net.h>
- #ifndef PTRACE_SETOPTIONS
- #define PTRACE_SETOPTIONS 0x4200
- #endif
- #ifndef PTRACE_O_TRACESYSGOOD
- #define PTRACE_O_TRACESYSGOOD 1
- #endif
- #ifndef PTRACE_O_TRACEFORK
- #define PTRACE_O_TRACEFORK 2
- #endif
- #ifndef PTRACE_O_TRACEVFORK
- #define PTRACE_O_TRACEVFORK 4
- #endif
- #ifndef PTRACE_O_TRACECLONE
- #define PTRACE_O_TRACECLONE 8
- #endif
- #ifndef O_DIRECT
- #define O_DIRECT 040000
- #endif
- static void sanitize_child();
- static int get_action(struct pt_sandbox* p_sandbox);
- static int validate_mmap2(struct pt_sandbox* p_sandbox, void* p_arg);
- static int validate_open_default(struct pt_sandbox* p_sandbox, void* p_arg);
- static int validate_open_readonly(struct pt_sandbox* p_sandbox, void* p_arg);
- static int validate_fcntl(struct pt_sandbox* p_sandbox, void* p_arg);
- static int validate_socketcall(struct pt_sandbox* p_sandbox, void* p_arg);
- static void install_socketcall(struct pt_sandbox* p_sandbox);
- #define MAX_SYSCALL 300
- struct pt_sandbox
- {
- int read_event_fd;
- int write_event_fd;
- pid_t pid;
- int is_allowed[MAX_SYSCALL];
- ptrace_sandbox_validator_t validator[MAX_SYSCALL];
- void* validator_arg[MAX_SYSCALL];
- int is_exit;
- struct user_regs_struct regs;
- int is_socketcall_allowed[NPROTO];
- ptrace_sandbox_validator_t socketcall_validator[NPROTO];
- void* socketcall_validator_arg[NPROTO];
- };
- static int s_sigchld_fd = -1;
- void
- handle_sigchld(int sig)
- {
- int ret;
- if (sig != SIGCHLD)
- {
- _exit(1);
- }
- if (s_sigchld_fd != -1)
- {
- do
- {
- static const char zero = ' ';
- ret = write(s_sigchld_fd, &zero, sizeof(zero));
- } while (ret == -1 && errno == EINTR);
- if (ret != 1)
- {
- _exit(2);
- }
- }
- }
- struct pt_sandbox*
- ptrace_sandbox_alloc()
- {
- int i;
- struct sigaction sigact;
- struct pt_sandbox* ret = malloc(sizeof(struct pt_sandbox));
- if (ret == NULL)
- {
- return NULL;
- }
- ret->pid = -1;
- ret->read_event_fd = -1;
- ret->write_event_fd = -1;
- ret->is_exit = 0;
- memset(&ret->regs, ' ', sizeof(ret->regs));
- for (i = 0; i < MAX_SYSCALL; ++i)
- {
- ret->is_allowed[i] = 0;
- ret->validator[i] = 0;
- ret->validator_arg[i] = 0;
- }
- for (i = 0; i < NPROTO; ++i)
- {
- ret->is_socketcall_allowed[i] = 0;
- ret->socketcall_validator[i] = 0;
- ret->socketcall_validator_arg[i] = 0;
- }
- memset((void*) &sigact, ' ', sizeof(sigact));
- sigact.sa_handler = handle_sigchld;
- if (sigaction(SIGCHLD, &sigact, NULL) != 0)
- {
- goto err_out;
- }
- return ret;
- err_out:
- ptrace_sandbox_free(ret);
- return NULL;
- }
- void
- ptrace_sandbox_free(struct pt_sandbox* p_sandbox)
- {
- if (p_sandbox->pid != -1)
- {
- warnx("bug: pid active in ptrace_sandbox_free");
- /* We'll kill it for you so it doesn't escape the sandbox totally, but
- * we won't reap the zombie.
- * Killing it like this is a risk: if it's stopped in syscall entry,
- * that syscall will execute before the pending kill takes effect.
- * If that pending syscall were to be a fork(), there could be trouble.
- */
- (void) kill(p_sandbox->pid, SIGKILL);
- }
- if (p_sandbox->read_event_fd != -1)
- {
- s_sigchld_fd = -1;
- close(p_sandbox->read_event_fd);
- close(p_sandbox->write_event_fd);
- }
- free(p_sandbox);
- }
- void
- ptrace_sandbox_attach_point()
- {
- long pt_ret;
- int ret;
- pid_t pid = getpid();
- if (pid <= 1)
- {
- warnx("weird pid");
- _exit(1);
- }
- /* You don't have to use PTRACE_TRACEME, but if you don't, a rogue SIGCONT
- * might wake you up from the STOP below before the tracer has attached.
- */
- pt_ret = ptrace(PTRACE_TRACEME, 0, 0, 0);
- if (pt_ret != 0)
- {
- warn("PTRACE_TRACEME failed");
- _exit(2);
- }
- ret = kill(pid, SIGSTOP);
- if (ret != 0)
- {
- warn("kill SIGSTOP failed");
- _exit(3);
- }
- }
- int
- ptrace_sandbox_launch_process(struct pt_sandbox* p_sandbox,
- void (*p_func)(void*),
- void* p_arg)
- {
- long pt_ret;
- pid_t ret;
- int status;
- if (p_sandbox->pid != -1)
- {
- warnx("bug: process already active");
- return -1;
- }
- ret = fork();
- if (ret < 0)
- {
- return -1;
- }
- else if (ret == 0)
- {
- /* Child context. */
- sanitize_child();
- (*p_func)(p_arg);
- _exit(0);
- }
- /* Parent context */
- p_sandbox->pid = ret;
- do
- {
- ret = waitpid(p_sandbox->pid, &status, 0);
- } while (ret == -1 && errno == EINTR);
- if (ret == -1)
- {
- warn("waitpid failed");
- goto kill_out;
- }
- else if (ret != p_sandbox->pid)
- {
- warnx("unknown pid %d", ret);
- goto kill_out;
- }
- if (!WIFSTOPPED(status))
- {
- warnx("not stopped status %dn", status);
- goto kill_out;
- }
- if (WSTOPSIG(status) != SIGSTOP)
- {
- warnx("not SIGSTOP status %dn", status);
- goto kill_out;
- }
- /* The fork, etc. tracing options are worth a bit of explanation. We don't
- * permit process launching syscalls at all as they are dangerous. But
- * there's a small race if the untrusted process attempts a denied fork()
- * and then takes a rouge SIGKILL before the supervisor gets a chance to
- * clear the orig_eax register. In this case the syscall will still execute.
- * (Policies may not include signal sending capabilities, thus mitigating this
- * direct attack, however a rogue SIGKILL may come from a non-malicious
- * source). Therefore, we'd rather any fork()ed process starts off traced,
- * just in case this tiny race condition triggers.
- */
- pt_ret = ptrace(PTRACE_SETOPTIONS,
- p_sandbox->pid,
- 0,
- PTRACE_O_TRACESYSGOOD | PTRACE_O_TRACEFORK |
- PTRACE_O_TRACEVFORK | PTRACE_O_TRACECLONE);
- if (pt_ret != 0)
- {
- warn("PTRACE_SETOPTIONS failure");
- goto kill_out;
- }
- return p_sandbox->pid;
- kill_out:
- (void) kill(p_sandbox->pid, SIGKILL);
- p_sandbox->pid = -1;
- return -1;
- }
- int
- ptrace_sandbox_continue_process(struct pt_sandbox* p_sandbox, int sig)
- {
- long pt_ret = ptrace(PTRACE_SYSCALL, p_sandbox->pid, 0, sig);
- if (pt_ret != 0)
- {
- warn("PTRACE_SYSCALL failure");
- if (errno == ESRCH)
- {
- return PTRACE_SANDBOX_ERR_DEAD;
- }
- return PTRACE_SANDBOX_ERR_PTRACE;
- }
- return 0;
- }
- int
- ptrace_sandbox_get_event_fd(struct pt_sandbox* p_sandbox)
- {
- /* TODO: allocate pipe fds */
- (void) p_sandbox;
- return -1;
- }
- int
- ptrace_sandbox_get_event(struct pt_sandbox* p_sandbox, int* status, int block)
- {
- pid_t pid;
- int options = 0;
- if (!block)
- {
- options = WNOHANG;
- }
- do
- {
- pid = waitpid(p_sandbox->pid, status, options);
- } while (pid == -1 && errno == EINTR);
- if (pid == -1)
- {
- warn("waitpid failure");
- if (errno == ECHILD)
- {
- return PTRACE_SANDBOX_ERR_DEAD;
- }
- return PTRACE_SANDBOX_ERR_WAITPID;
- }
- return pid;
- }
- int
- ptrace_sandbox_handle_event(struct pt_sandbox* p_sandbox, int status)
- {
- int sig;
- int action;
- if (WIFEXITED(status) || WIFSIGNALED(status))
- {
- p_sandbox->pid = -1;
- return 1;
- }
- if (!WIFSTOPPED(status))
- {
- warnx("weird status: %dn", status);
- return PTRACE_SANDBOX_ERR_WAIT_STATUS;
- }
- sig = WSTOPSIG(status);
- if (sig >= 0 && sig < 0x80)
- {
- /* It's a normal signal; deliver it right on. SIGSTOP / SIGCONT handling
- * are buggy in the kernel and I'm not sure it's safe to pass either on,
- * so the signal becomes a little more... robust :)
- */
- if (sig == SIGSTOP || sig == SIGCONT)
- {
- sig = SIGKILL;
- }
- return ptrace_sandbox_continue_process(p_sandbox, sig);
- }
- if (!(sig & 0x80))
- {
- warnx("weird status: %dn", status);
- return PTRACE_SANDBOX_ERR_WAIT_STATUS;
- }
- /* Syscall trap. */
- if (p_sandbox->is_exit)
- {
- p_sandbox->is_exit = 0;
- }
- else
- {
- p_sandbox->is_exit = 1;
- action = get_action(p_sandbox);
- if (action != 0)
- {
- return action;
- }
- }
- return ptrace_sandbox_continue_process(p_sandbox, 0);
- }
- int
- ptrace_sandbox_run_processes(struct pt_sandbox* p_sandbox)
- {
- if (ptrace_sandbox_continue_process(p_sandbox, 0) != 0)
- {
- goto kill_out;
- }
- while (1)
- {
- int status;
- int ret = ptrace_sandbox_get_event(p_sandbox, &status, 1);
- if (ret <= 0)
- {
- goto kill_out;
- }
- ret = ptrace_sandbox_handle_event(p_sandbox, status);
- if (ret < 0)
- {
- warnx("couldn't handle sandbox event");
- goto kill_out;
- }
- if (ret == 1)
- {
- return 0;
- }
- }
- kill_out:
- ptrace_sandbox_kill_processes(p_sandbox);
- return -1;
- }
- void
- ptrace_sandbox_kill_processes(struct pt_sandbox* p_sandbox)
- {
- long pt_ret;
- struct user_regs_struct regs;
- pid_t pid = p_sandbox->pid;
- if (pid == -1)
- {
- return;
- }
- p_sandbox->pid = -1;
- pt_ret = ptrace(PTRACE_GETREGS, pid, 0, ®s);
- if (pt_ret != 0)
- {
- warn("PTRACE_GETREGS failure");
- /* This API is supposed to be called with the process stopped; but if it
- * is still running, we can at least help a bit. See security related
- * comment in ptrace_sandbox_free(), though.
- */
- (void) kill(pid, SIGKILL);
- return;
- }
- /* Kind of nasty, but the only way of stopping a started syscall from
- * executing is to rewrite the registers to execute a different syscall.
- */
- regs.orig_eax = __NR_exit_group;
- regs.eip = 0xffffffff;
- pt_ret = ptrace(PTRACE_SETREGS, pid, 0, ®s);
- if (pt_ret != 0)
- {
- warn("PTRACE_SETREGS failure");
- /* Deliberate fall-thru. */
- }
- pt_ret = ptrace(PTRACE_KILL, pid, 0, 0);
- if (pt_ret != 0)
- {
- warn("PTRACE_KILL failure");
- /* Deliberate fall-thru. */
- }
- /* Just to make ourselves clear. */
- (void) kill(pid, SIGKILL);
- /* So the GETREGS succeeded, so the process definitely _was_ there. We can
- * safely wait for it to reap the zombie.
- */
- (void) waitpid(pid, NULL, 0);
- }
- int
- ptrace_sandbox_get_arg(struct pt_sandbox* p_sandbox,
- int arg,
- unsigned long* p_out)
- {
- long ret = 0;
- struct user_regs_struct* p_regs = &p_sandbox->regs;
- if (p_regs->orig_eax == 0)
- {
- return PTRACE_SANDBOX_ERR_API_ABUSE_STOPIT;
- }
- if (arg < 0 || arg > 5)
- {
- return PTRACE_SANDBOX_ERR_API_ABUSE_STOPIT;
- }
- switch (arg)
- {
- case 0:
- ret = p_regs->ebx;
- break;
- case 1:
- ret = p_regs->ecx;
- break;
- case 2:
- ret = p_regs->edx;
- break;
- case 3:
- ret = p_regs->esi;
- break;
- case 4:
- ret = p_regs->edi;
- break;
- case 5:
- ret = p_regs->ebp;
- break;
- }
- *p_out = ret;
- return 0;
- }
- int
- ptrace_sandbox_get_socketcall_arg(struct pt_sandbox* p_sandbox,
- int arg,
- unsigned long* p_out)
- {
- unsigned long ptr;
- int ret;
- struct user_regs_struct* p_regs = &p_sandbox->regs;
- if (p_regs->orig_eax == 0)
- {
- return PTRACE_SANDBOX_ERR_API_ABUSE_STOPIT;
- }
- if (arg < 0 || arg > 2)
- {
- return PTRACE_SANDBOX_ERR_API_ABUSE_STOPIT;
- }
- ret = ptrace_sandbox_get_arg(p_sandbox, 1, &ptr);
- if (ret != 0)
- {
- return ret;
- }
- ptr += (arg * 4);
- ret = ptrace_sandbox_get_long(p_sandbox, ptr, p_out);
- return ret;
- }
- int
- ptrace_sandbox_get_long(struct pt_sandbox* p_sandbox,
- unsigned long ptr,
- unsigned long* p_out)
- {
- return ptrace_sandbox_get_buf(p_sandbox, ptr, sizeof(long), (void*) p_out);
- }
- int
- ptrace_sandbox_get_buf(struct pt_sandbox* p_sandbox,
- unsigned long ptr,
- unsigned long len,
- void* p_buf)
- {
- long pt_ret;
- char* p_out = (char*) p_buf;
- for (; len > 0; len -= sizeof(long))
- {
- errno = 0;
- pt_ret = ptrace(PTRACE_PEEKDATA, p_sandbox->pid, (void*) ptr, 0);
- if (pt_ret == -1 && errno != 0)
- {
- warn("PTRACE_GETREGS failure");
- if (errno == ESRCH)
- {
- return PTRACE_SANDBOX_ERR_DEAD;
- }
- return PTRACE_SANDBOX_ERR_PTRACE;
- }
- if (len >= sizeof(long))
- {
- memcpy(p_out, &pt_ret, sizeof(long));
- }
- else
- {
- memcpy(p_out, &pt_ret, len);
- }
- p_out += sizeof(long);
- ptr += sizeof(long);
- }
- return 0;
- }
- static void
- sanitize_child()
- {
- /* Ensure that if our sandbox supervisor goes down, so do we. */
- int ret = prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
- if (ret != 0)
- {
- _exit(3);
- }
- }
- static int
- get_action(struct pt_sandbox* p_sandbox)
- {
- int ret;
- int call;
- int cs;
- long pt_ret = ptrace(PTRACE_GETREGS, p_sandbox->pid, 0, &(p_sandbox->regs));
- if (pt_ret != 0)
- {
- warn("PTRACE_GETREGS failure");
- if (errno == ESRCH)
- {
- return PTRACE_SANDBOX_ERR_DEAD;
- }
- return PTRACE_SANDBOX_ERR_PTRACE;
- }
- /* We need to be sure that the child is attempting a syscall against the
- * 32-bit syscall table, otherwise they can bypass the policy by abusing the
- * fact that e.g. syscall 200 is getgid32() on 32-bit but tkill() on 64-bit.
- * If the syscall instruct was int80 or sysenter, is it guaranteed to hit
- * the 32-bit table. If it is syscall, the current CS selector determines
- * the table. Therefore, we can check the current CS selector references a
- * known system-only selector that is guaranteed 32-bit (not long mode).
- */
- cs = p_sandbox->regs.xcs;
- if (cs != 0x73 && cs != 0x23)
- {
- warnx("bad CS %d", cs);
- ret = PTRACE_SANDBOX_ERR_BAD_SYSCALL;
- goto out;
- }
- call = (int) p_sandbox->regs.orig_eax;
- if (call < 0 || call >= MAX_SYSCALL)
- {
- warnx("syscall %d out of bounds", call);
- ret = PTRACE_SANDBOX_ERR_BAD_SYSCALL;
- goto out;
- }
- if (p_sandbox->is_allowed[call] != 1)
- {
- syslog(LOG_LOCAL0 | LOG_DEBUG, "syscall not permitted: %d", call);
- warnx("syscall not permitted: %d", call);
- ret = PTRACE_SANDBOX_ERR_POLICY_SYSCALL;
- goto out;
- }
- if (p_sandbox->validator[call])
- {
- ptrace_sandbox_validator_t p_validate = p_sandbox->validator[call];
- int validate_ret = (*p_validate)(p_sandbox, p_sandbox->validator_arg[call]);
- if (validate_ret != 0)
- {
- syslog(LOG_LOCAL0 | LOG_DEBUG,
- "syscall validate fail: %d (%d)",
- call,
- validate_ret);
- warnx("syscall validate failed: %d (%d)", call, validate_ret);
- ret = PTRACE_SANDBOX_ERR_POLICY_ARGS;
- goto out;
- }
- }
- ret = 0;
- out:
- memset(&p_sandbox->regs, ' ', sizeof(&p_sandbox->regs));
- return ret;
- }
- void
- ptrace_sandbox_permit_exit(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_exit] = 1;
- p_sandbox->is_allowed[__NR_exit_group] = 1;
- }
- void
- ptrace_sandbox_permit_read(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_read] = 1;
- }
- void
- ptrace_sandbox_permit_write(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_write] = 1;
- }
- void
- ptrace_sandbox_permit_sigaction(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_sigaction] = 1;
- p_sandbox->is_allowed[__NR_rt_sigaction] = 1;
- }
- void
- ptrace_sandbox_permit_alarm(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_alarm] = 1;
- }
- void
- ptrace_sandbox_permit_query_time(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_gettimeofday] = 1;
- p_sandbox->is_allowed[__NR_time] = 1;
- }
- void
- ptrace_sandbox_permit_mmap(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_mmap2] = 1;
- p_sandbox->validator[__NR_mmap2] = validate_mmap2;
- }
- static int
- validate_mmap2(struct pt_sandbox* p_sandbox, void* p_arg)
- {
- unsigned long arg4;
- int ret = ptrace_sandbox_get_arg(p_sandbox, 3, &arg4);
- (void) p_arg;
- if (ret != 0)
- {
- return ret;
- }
- if (arg4 & MAP_SHARED)
- {
- return -1;
- }
- return 0;
- }
- void
- ptrace_sandbox_permit_mprotect(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_mprotect] = 1;
- }
- void
- ptrace_sandbox_permit_file_stats(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_stat] = 1;
- p_sandbox->is_allowed[__NR_stat64] = 1;
- p_sandbox->is_allowed[__NR_lstat] = 1;
- p_sandbox->is_allowed[__NR_lstat64] = 1;
- }
- void
- ptrace_sandbox_permit_fd_stats(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_fstat] = 1;
- p_sandbox->is_allowed[__NR_fstat64] = 1;
- }
- void
- ptrace_sandbox_permit_getcwd(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_getcwd] = 1;
- }
- void
- ptrace_sandbox_permit_chdir(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_chdir] = 1;
- }
- void
- ptrace_sandbox_permit_umask(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_umask] = 1;
- }
- void
- ptrace_sandbox_permit_open(struct pt_sandbox* p_sandbox, int writeable)
- {
- p_sandbox->is_allowed[__NR_open] = 1;
- if (writeable == 1)
- {
- p_sandbox->validator[__NR_open] = validate_open_default;
- }
- else
- {
- p_sandbox->validator[__NR_open] = validate_open_readonly;
- }
- }
- static int
- validate_open_default(struct pt_sandbox* p_sandbox, void* p_arg)
- {
- unsigned long arg2;
- int ret = ptrace_sandbox_get_arg(p_sandbox, 1, &arg2);
- (void) p_arg;
- if (ret != 0)
- {
- return ret;
- }
- if (arg2 & (O_ASYNC | O_DIRECT | O_SYNC))
- {
- return -1;
- }
- return 0;
- }
- static int
- validate_open_readonly(struct pt_sandbox* p_sandbox, void* p_arg)
- {
- unsigned long arg2;
- int ret = validate_open_default(p_sandbox, p_arg);
- if (ret != 0)
- {
- return ret;
- }
- ret = ptrace_sandbox_get_arg(p_sandbox, 1, &arg2);
- if (ret != 0)
- {
- return ret;
- }
- if ((arg2 & O_ACCMODE) != O_RDONLY)
- {
- return -1;
- }
- return 0;
- }
- void
- ptrace_sandbox_permit_close(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_close] = 1;
- }
- void
- ptrace_sandbox_permit_getdents(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_getdents] = 1;
- p_sandbox->is_allowed[__NR_getdents64] = 1;
- }
- void
- ptrace_sandbox_permit_fcntl(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_fcntl] = 1;
- p_sandbox->validator[__NR_fcntl] = validate_fcntl;
- p_sandbox->is_allowed[__NR_fcntl64] = 1;
- p_sandbox->validator[__NR_fcntl64] = validate_fcntl;
- }
- static int
- validate_fcntl(struct pt_sandbox* p_sandbox, void* p_arg)
- {
- unsigned long arg2;
- unsigned long arg3;
- int ret = ptrace_sandbox_get_arg(p_sandbox, 1, &arg2);
- (void) p_arg;
- if (ret != 0)
- {
- return ret;
- }
- ret = ptrace_sandbox_get_arg(p_sandbox, 2, &arg3);
- if (ret != 0)
- {
- return ret;
- }
- if (arg2 != F_GETFL &&
- arg2 != F_SETFL &&
- arg2 != F_SETOWN &&
- arg2 != F_SETLK &&
- arg2 != F_SETLKW &&
- arg2 != F_SETLK64 &&
- arg2 != F_SETLKW64 &&
- arg2 != F_SETFD &&
- arg2 != F_GETFD)
- {
- syslog(LOG_LOCAL0 | LOG_DEBUG, "fcntl not permitted: %ld", arg2);
- warnx("fcntl not permitted: %ld", arg2);
- return -1;
- }
- if (arg2 == F_SETFL && (arg3 & (O_ASYNC | O_DIRECT)))
- {
- return -2;
- }
- if (arg2 == F_SETOWN && (int) arg3 != p_sandbox->pid)
- {
- return -3;
- }
- return 0;
- }
- void
- ptrace_sandbox_permit_sendfile(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_sendfile] = 1;
- p_sandbox->is_allowed[__NR_sendfile64] = 1;
- }
- void
- ptrace_sandbox_permit_seek(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_lseek] = 1;
- p_sandbox->is_allowed[__NR__llseek] = 1;
- }
- void
- ptrace_sandbox_permit_select(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_select] = 1;
- p_sandbox->is_allowed[__NR__newselect] = 1;
- }
- void
- ptrace_sandbox_permit_unlink(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_unlink] = 1;
- }
- void
- ptrace_sandbox_permit_mkdir(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_mkdir] = 1;
- }
- void
- ptrace_sandbox_permit_rmdir(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_rmdir] = 1;
- }
- void
- ptrace_sandbox_permit_rename(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_rename] = 1;
- }
- void
- ptrace_sandbox_permit_utime(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_utime] = 1;
- p_sandbox->is_allowed[__NR_utimes] = 1;
- }
- void
- ptrace_sandbox_permit_sigreturn(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_sigreturn] = 1;
- }
- void
- ptrace_sandbox_permit_recv(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_RECV] = 1;
- }
- static void
- install_socketcall(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_socketcall] = 1;
- p_sandbox->validator[__NR_socketcall] = validate_socketcall;
- }
- static int
- validate_socketcall(struct pt_sandbox* p_sandbox, void* p_arg)
- {
- unsigned long arg1;
- int ret = ptrace_sandbox_get_arg(p_sandbox, 0, &arg1);
- (void) p_arg;
- if (ret != 0)
- {
- return ret;
- }
- if (arg1 < 1 || arg1 >= NPROTO)
- {
- return -1;
- }
- if (p_sandbox->is_socketcall_allowed[arg1] != 1)
- {
- syslog(LOG_LOCAL0 | LOG_DEBUG, "socketcall not permitted: %ld", arg1);
- warnx("socketcall not permitted: %ld", arg1);
- return -2;
- }
- if (p_sandbox->socketcall_validator[arg1])
- {
- ptrace_sandbox_validator_t p_val = p_sandbox->socketcall_validator[arg1];
- ret = (*p_val)(p_sandbox, p_sandbox->socketcall_validator_arg[arg1]);
- if (ret != 0)
- {
- syslog(LOG_LOCAL0 | LOG_DEBUG,
- "socketcall validate fail: %ld (%d)",
- arg1,
- ret);
- warnx("socketcall validate fail: %ld (%d)", arg1, ret);
- return -3;
- }
- }
- return 0;
- }
- void
- ptrace_sandbox_permit_readlink(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_readlink] = 1;
- }
- void
- ptrace_sandbox_permit_brk(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_brk] = 1;
- }
- void
- ptrace_sandbox_permit_sleep(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_nanosleep] = 1;
- }
- void
- ptrace_sandbox_permit_fchmod(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_fchmod] = 1;
- }
- void
- ptrace_sandbox_permit_chmod(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_chmod] = 1;
- }
- void
- ptrace_sandbox_permit_fchown(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_fchown] = 1;
- p_sandbox->is_allowed[__NR_fchown32] = 1;
- }
- void
- ptrace_sandbox_permit_mremap(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_mremap] = 1;
- }
- void
- ptrace_sandbox_permit_ftruncate(struct pt_sandbox* p_sandbox)
- {
- p_sandbox->is_allowed[__NR_ftruncate] = 1;
- p_sandbox->is_allowed[__NR_ftruncate64] = 1;
- }
- void
- ptrace_sandbox_permit_socket(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_SOCKET] = 1;
- }
- void
- ptrace_sandbox_set_socket_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- p_sandbox->socketcall_validator[SYS_SOCKET] = val;
- p_sandbox->socketcall_validator_arg[SYS_SOCKET] = p_arg;
- }
- void
- ptrace_sandbox_permit_bind(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_BIND] = 1;
- }
- void
- ptrace_sandbox_set_bind_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- p_sandbox->socketcall_validator[SYS_BIND] = val;
- p_sandbox->socketcall_validator_arg[SYS_BIND] = p_arg;
- }
- void
- ptrace_sandbox_permit_connect(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_CONNECT] = 1;
- }
- void
- ptrace_sandbox_set_connect_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- p_sandbox->socketcall_validator[SYS_CONNECT] = val;
- p_sandbox->socketcall_validator_arg[SYS_CONNECT] = p_arg;
- }
- void
- ptrace_sandbox_permit_listen(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_LISTEN] = 1;
- }
- void
- ptrace_sandbox_permit_accept(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_ACCEPT] = 1;
- }
- void
- ptrace_sandbox_permit_setsockopt(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_SETSOCKOPT] = 1;
- }
- void
- ptrace_sandbox_set_setsockopt_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- p_sandbox->socketcall_validator[SYS_SETSOCKOPT] = val;
- p_sandbox->socketcall_validator_arg[SYS_SETSOCKOPT] = p_arg;
- }
- void
- ptrace_sandbox_permit_getsockopt(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_GETSOCKOPT] = 1;
- }
- void
- ptrace_sandbox_set_getsockopt_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- p_sandbox->socketcall_validator[SYS_GETSOCKOPT] = val;
- p_sandbox->socketcall_validator_arg[SYS_GETSOCKOPT] = p_arg;
- }
- void
- ptrace_sandbox_permit_shutdown(struct pt_sandbox* p_sandbox)
- {
- install_socketcall(p_sandbox);
- p_sandbox->is_socketcall_allowed[SYS_SHUTDOWN] = 1;
- }
- #else /* __linux__ && __i386__ */
- struct pt_sandbox*
- ptrace_sandbox_alloc()
- {
- return 0;
- }
- void
- ptrace_sandbox_free(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- int
- ptrace_sandbox_launch_process(struct pt_sandbox* p_sandbox,
- void (*p_func)(void*),
- void* p_arg)
- {
- (void) p_sandbox;
- (void) p_func;
- (void) p_arg;
- return -1;
- }
- int
- ptrace_sandbox_run_processes(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- return -1;
- }
- void
- ptrace_sandbox_attach_point(void)
- {
- }
- void
- ptrace_sandbox_permit_exit(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_read(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_write(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_sigaction(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_alarm(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_query_time(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_mmap(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_mprotect(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_file_stats(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_fd_stats(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_getcwd(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_chdir(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_umask(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_open(struct pt_sandbox* p_sandbox, int writeable)
- {
- (void) p_sandbox;
- (void) writeable;
- }
- void
- ptrace_sandbox_permit_close(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_getdents(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_fcntl(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_sendfile(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_seek(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_select(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_unlink(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_mkdir(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_rmdir(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_rename(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_utime(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_utimes(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_sigreturn(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_recv(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_kill_processes(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- int
- ptrace_sandbox_get_arg(struct pt_sandbox* p_sandbox,
- int arg,
- unsigned long* p_out)
- {
- (void) p_sandbox;
- (void) arg;
- (void) p_out;
- return -1;
- }
- int
- ptrace_sandbox_get_socketcall_arg(struct pt_sandbox* p_sandbox,
- int arg,
- unsigned long* p_out)
- {
- (void) p_sandbox;
- (void) arg;
- (void) p_out;
- return -1;
- }
- int
- ptrace_sandbox_get_long(struct pt_sandbox* p_sandbox,
- unsigned long ptr,
- unsigned long* p_out)
- {
- (void) p_sandbox;
- (void) ptr;
- (void) p_out;
- return -1;
- }
- int
- ptrace_sandbox_get_buf(struct pt_sandbox* p_sandbox,
- unsigned long ptr,
- unsigned long len,
- void* p_buf)
- {
- (void) p_sandbox;
- (void) ptr;
- (void) len;
- (void) p_buf;
- return -1;
- }
- void
- ptrace_sandbox_permit_readlink(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_brk(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_sleep(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_fchmod(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_chmod(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_fchown(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_mremap(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_ftruncate(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_socket(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_set_socket_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- (void) p_sandbox;
- (void) val;
- (void) p_arg;
- }
- void
- ptrace_sandbox_permit_bind(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_set_bind_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- (void) p_sandbox;
- (void) val;
- (void) p_arg;
- }
- void
- ptrace_sandbox_permit_connect(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_set_connect_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- (void) p_sandbox;
- (void) val;
- (void) p_arg;
- }
- void
- ptrace_sandbox_permit_listen(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_accept(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_permit_setsockopt(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_set_setsockopt_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- (void) p_sandbox;
- (void) val;
- (void) p_arg;
- }
- void
- ptrace_sandbox_permit_getsockopt(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- void
- ptrace_sandbox_set_getsockopt_validator(struct pt_sandbox* p_sandbox,
- ptrace_sandbox_validator_t val,
- void* p_arg)
- {
- (void) p_sandbox;
- (void) val;
- (void) p_arg;
- }
- void
- ptrace_sandbox_permit_shutdown(struct pt_sandbox* p_sandbox)
- {
- (void) p_sandbox;
- }
- #endif /* __linux__ && __i386__ */