freebsd-dev/sys/sys/imgact.h
Bryan Drewery 881010f05d exec: Add credential change information into imgp for process_exec hook.
This allows an EVENTHANDLER(process_exec) hook to see if the new image
will cause credentials to change whether due to setgid/setuid or because
of POSIX saved-id semantics.

This adds 3 new fields into image_params:
  struct ucred *newcred		Non-null if the credentials will change.
  bool credential_setid		True if the new image is setuid or setgid.

This will pre-determine the new credentials before invoking the image
activators, where the process_exec hook is called.  The new credentials
will be installed into the process in the same place as before, after
image activators are done handling the image.

MFC after:	2 weeks
Reviewed by:	kib
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D6544
2016-05-26 23:18:54 +00:00

114 lines
4.4 KiB
C

/*-
* Copyright (c) 1993, David Greenman
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_IMGACT_H_
#define _SYS_IMGACT_H_
#include <sys/uio.h>
#include <vm/vm.h>
#define MAXSHELLCMDLEN PAGE_SIZE
struct ucred;
struct image_args {
char *buf; /* pointer to string buffer */
char *begin_argv; /* beginning of argv in buf */
char *begin_envv; /* beginning of envv in buf */
char *endp; /* current `end' pointer of arg & env strings */
char *fname; /* pointer to filename of executable (system space) */
char *fname_buf; /* pointer to optional malloc(M_TEMP) buffer */
int stringspace; /* space left in arg & env buffer */
int argc; /* count of argument strings */
int envc; /* count of environment strings */
int fd; /* file descriptor of the executable */
struct filedesc *fdp; /* new file descriptor table */
};
struct image_params {
struct proc *proc; /* our process struct */
struct label *execlabel; /* optional exec label */
struct vnode *vp; /* pointer to vnode of file to exec */
struct vm_object *object; /* The vm object for this vp */
struct vattr *attr; /* attributes of file */
const char *image_header; /* head of file to exec */
unsigned long entry_addr; /* entry address of target executable */
unsigned long reloc_base; /* load address of image */
char vmspace_destroyed; /* flag - we've blown away original vm space */
#define IMGACT_SHELL 0x1
#define IMGACT_BINMISC 0x2
unsigned char interpreted; /* mask of interpreters that have run */
char opened; /* flag - we have opened executable vnode */
char *interpreter_name; /* name of the interpreter */
void *auxargs; /* ELF Auxinfo structure pointer */
struct sf_buf *firstpage; /* first page that we mapped */
unsigned long ps_strings; /* PS_STRINGS for BSD/OS binaries */
size_t auxarg_size;
struct image_args *args; /* system call arguments */
struct sysentvec *sysent; /* system entry vector */
char *execpath;
unsigned long execpathp;
char *freepath;
unsigned long canary;
int canarylen;
unsigned long pagesizes;
int pagesizeslen;
vm_prot_t stack_prot;
u_long stack_sz;
struct ucred *newcred; /* new credentials if changing */
bool credential_setid; /* true if becoming setid */
};
#ifdef _KERNEL
struct sysentvec;
struct thread;
struct vmspace;
#define IMGACT_CORE_COMPRESS 0x01
int exec_alloc_args(struct image_args *);
int exec_check_permissions(struct image_params *);
register_t *exec_copyout_strings(struct image_params *);
void exec_free_args(struct image_args *);
int exec_new_vmspace(struct image_params *, struct sysentvec *);
void exec_setregs(struct thread *, struct image_params *, u_long);
int exec_shell_imgact(struct image_params *);
int exec_copyin_args(struct image_args *, char *, enum uio_seg,
char **, char **);
int exec_copyin_data_fds(struct thread *, struct image_args *, const void *,
size_t, const int *, size_t);
int pre_execve(struct thread *td, struct vmspace **oldvmspace);
void post_execve(struct thread *td, int error, struct vmspace *oldvmspace);
#endif
#endif /* !_SYS_IMGACT_H_ */