diff options
Diffstat (limited to 'sandbox-systrace.c')
| -rw-r--r-- | sandbox-systrace.c | 198 |
1 files changed, 0 insertions, 198 deletions
diff --git a/sandbox-systrace.c b/sandbox-systrace.c deleted file mode 100644 index 5a39f4fe..00000000 --- a/sandbox-systrace.c +++ /dev/null @@ -1,198 +0,0 @@ -/* $OpenBSD: sandbox-systrace.c,v 1.4 2011/07/29 14:42:45 djm Exp $ */ -/* - * Copyright (c) 2011 Damien Miller <djm@mindrot.org> - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR - * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN - * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF - * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. - */ - -#include "includes.h" - -#ifdef SANDBOX_SYSTRACE - -#include <sys/types.h> -#include <sys/param.h> -#include <sys/ioctl.h> -#include <sys/syscall.h> -#include <sys/socket.h> - -#include <dev/systrace.h> - -#include <errno.h> -#include <fcntl.h> -#include <limits.h> -#include <stdarg.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include "atomicio.h" -#include "log.h" -#include "ssh-sandbox.h" -#include "xmalloc.h" - -struct sandbox_policy { - int syscall; - int action; -}; - -/* Permitted syscalls in preauth. Unlisted syscalls get SYSTR_POLICY_KILL */ -static const struct sandbox_policy preauth_policy[] = { - { SYS_open, SYSTR_POLICY_NEVER }, - - { SYS___sysctl, SYSTR_POLICY_PERMIT }, - { SYS_close, SYSTR_POLICY_PERMIT }, - { SYS_exit, SYSTR_POLICY_PERMIT }, - { SYS_getpid, SYSTR_POLICY_PERMIT }, - { SYS_gettimeofday, SYSTR_POLICY_PERMIT }, - { SYS_madvise, SYSTR_POLICY_PERMIT }, - { SYS_mmap, SYSTR_POLICY_PERMIT }, - { SYS_mprotect, SYSTR_POLICY_PERMIT }, - { SYS_poll, SYSTR_POLICY_PERMIT }, - { SYS_munmap, SYSTR_POLICY_PERMIT }, - { SYS_read, SYSTR_POLICY_PERMIT }, - { SYS_select, SYSTR_POLICY_PERMIT }, - { SYS_sigprocmask, SYSTR_POLICY_PERMIT }, - { SYS_write, SYSTR_POLICY_PERMIT }, - { -1, -1 } -}; - -struct ssh_sandbox { - int child_sock; - int parent_sock; - int systrace_fd; - pid_t child_pid; -}; - -struct ssh_sandbox * -ssh_sandbox_init(void) -{ - struct ssh_sandbox *box; - int s[2]; - - debug3("%s: preparing systrace sandbox", __func__); - box = xcalloc(1, sizeof(*box)); - if (socketpair(AF_UNIX, SOCK_STREAM, 0, s) == -1) - fatal("%s: socketpair: %s", __func__, strerror(errno)); - box->child_sock = s[0]; - box->parent_sock = s[1]; - box->systrace_fd = -1; - box->child_pid = 0; - - return box; -} - -void -ssh_sandbox_child(struct ssh_sandbox *box) -{ - char whatever = 0; - - close(box->parent_sock); - /* Signal parent that we are ready */ - debug3("%s: ready", __func__); - if (atomicio(vwrite, box->child_sock, &whatever, 1) != 1) - fatal("%s: write: %s", __func__, strerror(errno)); - /* Wait for parent to signal for us to go */ - if (atomicio(read, box->child_sock, &whatever, 1) != 1) - fatal("%s: read: %s", __func__, strerror(errno)); - debug3("%s: started", __func__); - close(box->child_sock); -} - -static void -ssh_sandbox_parent(struct ssh_sandbox *box, pid_t child_pid, - const struct sandbox_policy *allowed_syscalls) -{ - int dev_systrace, i, j, found; - char whatever = 0; - struct systrace_policy policy; - - debug3("%s: wait for child %ld", __func__, (long)child_pid); - box->child_pid = child_pid; - close(box->child_sock); - /* Wait for child to signal that it is ready */ - if (atomicio(read, box->parent_sock, &whatever, 1) != 1) - fatal("%s: read: %s", __func__, strerror(errno)); - debug3("%s: child %ld ready", __func__, (long)child_pid); - - /* Set up systracing of child */ - if ((dev_systrace = open("/dev/systrace", O_RDONLY)) == -1) - fatal("%s: open(\"/dev/systrace\"): %s", __func__, - strerror(errno)); - if (ioctl(dev_systrace, STRIOCCLONE, &box->systrace_fd) == -1) - fatal("%s: ioctl(STRIOCCLONE, %d): %s", __func__, - dev_systrace, strerror(errno)); - close(dev_systrace); - debug3("%s: systrace attach, fd=%d", __func__, box->systrace_fd); - if (ioctl(box->systrace_fd, STRIOCATTACH, &child_pid) == -1) - fatal("%s: ioctl(%d, STRIOCATTACH, %d): %s", __func__, - box->systrace_fd, child_pid, strerror(errno)); - - /* Allocate and assign policy */ - bzero(&policy, sizeof(policy)); - policy.strp_op = SYSTR_POLICY_NEW; - policy.strp_maxents = SYS_MAXSYSCALL; - if (ioctl(box->systrace_fd, STRIOCPOLICY, &policy) == -1) - fatal("%s: ioctl(%d, STRIOCPOLICY (new)): %s", __func__, - box->systrace_fd, strerror(errno)); - - policy.strp_op = SYSTR_POLICY_ASSIGN; - policy.strp_pid = box->child_pid; - if (ioctl(box->systrace_fd, STRIOCPOLICY, &policy) == -1) - fatal("%s: ioctl(%d, STRIOCPOLICY (assign)): %s", - __func__, box->systrace_fd, strerror(errno)); - - /* Set per-syscall policy */ - for (i = 0; i < SYS_MAXSYSCALL; i++) { - found = 0; - for (j = 0; allowed_syscalls[j].syscall != -1; j++) { - if (allowed_syscalls[j].syscall == i) { - found = 1; - break; - } - } - policy.strp_op = SYSTR_POLICY_MODIFY; - policy.strp_code = i; - policy.strp_policy = found ? - allowed_syscalls[j].action : SYSTR_POLICY_KILL; - if (found) - debug3("%s: policy: enable syscall %d", __func__, i); - if (ioctl(box->systrace_fd, STRIOCPOLICY, &policy) == -1) - fatal("%s: ioctl(%d, STRIOCPOLICY (modify)): %s", - __func__, box->systrace_fd, strerror(errno)); - } - - /* Signal the child to start running */ - debug3("%s: start child %ld", __func__, (long)child_pid); - if (atomicio(vwrite, box->parent_sock, &whatever, 1) != 1) - fatal("%s: write: %s", __func__, strerror(errno)); - close(box->parent_sock); -} - -void -ssh_sandbox_parent_finish(struct ssh_sandbox *box) -{ - /* Closing this before the child exits will terminate it */ - close(box->systrace_fd); - - free(box); - debug3("%s: finished", __func__); -} - -void -ssh_sandbox_parent_preauth(struct ssh_sandbox *box, pid_t child_pid) -{ - ssh_sandbox_parent(box, child_pid, preauth_policy); -} - -#endif /* SANDBOX_SYSTRACE */ |