NetBSD/bin/systrace/intercept.h
provos 61e8c76047 support for privilege elevation.
with privilege elevation no suid or sgid binaries are necessary any
longer.  Applications can be executed completely unprivileged. Systrace
raises the privileges for a single system call depending on the
configured policy.

Idea from discussions with Perry Metzger, Dug Song and Marcus Watts.
Approved by christos and thorpej.
2002-10-11 21:54:55 +00:00

195 lines
6.8 KiB
C

/* $NetBSD: intercept.h,v 1.6 2002/10/11 21:54:57 provos Exp $ */
/* $OpenBSD: intercept.h,v 1.11 2002/08/04 04:15:50 provos Exp $ */
/*
* Copyright 2002 Niels Provos <provos@citi.umich.edu>
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Niels Provos.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifndef _INTERCEPT_H_
#define _INTERCEPT_H_
#include <sys/param.h>
#include <sys/queue.h>
struct intercept_pid;
struct intercept_replace;
struct elevate;
struct intercept_system {
char *name;
int (*init)(void);
int (*open)(void);
int (*attach)(int, pid_t);
int (*detach)(int, pid_t);
int (*report)(int, pid_t);
int (*read)(int);
int (*getsyscallnumber)(const char *, const char *);
char *(*getcwd)(int, pid_t, char *, size_t);
int (*restcwd)(int);
int (*io)(int, pid_t, int, void *, u_char *, size_t);
int (*getarg)(int, void *, int, void **);
int (*answer)(int, pid_t, u_int32_t, short, int, short,
struct elevate *);
int (*newpolicy)(int);
int (*assignpolicy)(int, pid_t, int);
int (*policy)(int, int, int, short);
int (*replace)(int, pid_t, struct intercept_replace *);
void (*clonepid)(struct intercept_pid *, struct intercept_pid *);
void (*freepid)(struct intercept_pid *);
};
#define INTERCEPT_READ 1
#define INTERCEPT_WRITE 2
#define ICPOLICY_ASK 0
#define ICPOLICY_PERMIT -1
#define ICPOLICY_KILL -2
#define ICPOLICY_NEVER 1 /* overloaded with errno values > 1 */
#define ICLINK_NONE 0 /* do not resolve symlinks */
#define ICLINK_ALL 1 /* resolve all symlinks */
#define ICLINK_NOLAST 2 /* do not resolve last component */
#define ICFLAGS_RESULT 1
/* Privilege elevation */
struct elevate {
#define ELEVATE_UID 0x01
#define ELEVATE_GID 0x02
int e_flags;
uid_t e_uid;
gid_t e_gid;
};
struct intercept_pid {
SPLAY_ENTRY(intercept_pid) next;
pid_t pid;
pid_t ppid; /* parent pid */
short policynr;
int execve_code;
short execve_policy;
char *name; /* name of current process image */
char *newname; /* image name to be committed by execve */
uid_t uid; /* current uid */
gid_t gid; /* current gid */
char username[MAXLOGNAME];
char home[MAXPATHLEN]; /* current home dir for uid */
char cwd[MAXPATHLEN]; /* current working directory */
void *data;
int uflags; /* Flags that can be used by external application */
struct elevate *elevate; /* privilege elevation request */
};
#define INTERCEPT_MAXSYSCALLARGS 10
struct intercept_translate {
char *name;
int (*translate)(struct intercept_translate *, int, pid_t, void *);
int (*print)(char *, size_t, struct intercept_translate *);
int off2;
int off;
u_char trans_valid;
void *trans_addr;
void *trans_addr2;
void *trans_data;
size_t trans_size;
char *trans_print;
TAILQ_ENTRY(intercept_translate) next;
};
struct intercept_replace {
int num;
int ind[INTERCEPT_MAXSYSCALLARGS];
u_char *address[INTERCEPT_MAXSYSCALLARGS];
size_t len[INTERCEPT_MAXSYSCALLARGS];
};
TAILQ_HEAD(intercept_tlq, intercept_translate);
int intercept_init(void);
pid_t intercept_run(int, int, uid_t, gid_t, char *, char * const *);
int intercept_open(void);
int intercept_attach(int, pid_t);
int intercept_attachpid(int, pid_t, char *);
int intercept_detach(int, pid_t);
int intercept_read(int);
int intercept_newpolicy(int);
int intercept_assignpolicy(int, pid_t, int);
int intercept_modifypolicy(int, int, const char *, const char *, short);
void intercept_child_info(pid_t, pid_t);
int intercept_replace_init(struct intercept_replace *);
int intercept_replace_add(struct intercept_replace *, int, u_char *, size_t);
int intercept_replace(int, pid_t, struct intercept_replace *);
int intercept_register_sccb(char *, char *,
short (*)(int, pid_t, int, const char *, int, const char *, void *, int,
struct intercept_tlq *, void *),
void *);
void *intercept_sccb_cbarg(char *, char *);
int intercept_register_gencb(short (*)(int, pid_t, int, const char *, int, const char *, void *, int, void *), void *);
int intercept_register_execcb(void (*)(int, pid_t, int, const char *, const char *, void *), void *);
struct intercept_translate *intercept_register_translation(char *, char *,
int, struct intercept_translate *);
int intercept_translate(struct intercept_translate *, int, pid_t, int, void *, int);
char *intercept_translate_print(struct intercept_translate *);
#define intercept_register_transstring(x,y,z) \
intercept_register_translation(x, y, z, &ic_translate_string)
#define intercept_register_transfn(x,y,z) \
intercept_register_translation(x, y, z, &ic_translate_filename)
#define intercept_register_translink(x,y,z) \
intercept_register_translation(x, y, z, &ic_translate_linkname)
extern struct intercept_translate ic_translate_string;
extern struct intercept_translate ic_translate_filename;
extern struct intercept_translate ic_translate_linkname;
extern struct intercept_translate ic_translate_unlinkname;
extern struct intercept_translate ic_translate_connect;
void intercept_freepid(pid_t);
struct intercept_pid *intercept_getpid(pid_t);
int intercept_existpids(void);
char *intercept_get_string(int, pid_t, void *);
char *intercept_filename(int, pid_t, void *, int);
void intercept_syscall(int, pid_t, u_int16_t, int, const char *, int,
const char *, void *, int);
void intercept_syscall_result(int, pid_t, u_int16_t, int, const char *, int,
const char *, void *, int, int, void *);
void intercept_ugid(struct intercept_pid *, uid_t, gid_t);
void intercept_setpid(struct intercept_pid *, uid_t, gid_t);
#endif /* _INTERCEPT_H_ */