1#ifndef _LINUX_BINFMTS_H
2#define _LINUX_BINFMTS_H
3
4#include <linux/capability.h>
5
6struct pt_regs;
7
8/*
9 * These are the maximum length and maximum number of strings passed to the
10 * execve() system call.  MAX_ARG_STRLEN is essentially random but serves to
11 * prevent the kernel from being unduly impacted by misaddressed pointers.
12 * MAX_ARG_STRINGS is chosen to fit in a signed 32-bit integer.
13 */
14#define MAX_ARG_STRLEN (PAGE_SIZE * 32)
15#define MAX_ARG_STRINGS 0x7FFFFFFF
16
17/* sizeof(linux_binprm->buf) */
18#define BINPRM_BUF_SIZE 128
19
20#ifdef __KERNEL__
21#include <linux/sched.h>
22
23#define CORENAME_MAX_SIZE 128
24
25/*
26 * This structure is used to hold the arguments that are used when loading binaries.
27 */
28struct linux_binprm {
29	char buf[BINPRM_BUF_SIZE];
30#ifdef CONFIG_MMU
31	struct vm_area_struct *vma;
32	unsigned long vma_pages;
33#else
34# define MAX_ARG_PAGES	32
35	struct page *page[MAX_ARG_PAGES];
36#endif
37	struct mm_struct *mm;
38	unsigned long p; /* current top of mem */
39	unsigned int
40		cred_prepared:1,/* true if creds already prepared (multiple
41				 * preps happen for interpreters) */
42		cap_effective:1;/* true if has elevated effective capabilities,
43				 * false if not; except for init which inherits
44				 * its parent's caps anyway */
45#ifdef __alpha__
46	unsigned int taso:1;
47#endif
48	unsigned int recursion_depth;
49	struct file * file;
50	struct cred *cred;	/* new credentials */
51	int unsafe;		/* how unsafe this exec is (mask of LSM_UNSAFE_*) */
52	unsigned int per_clear;	/* bits to clear in current->personality */
53	int argc, envc;
54	const char * filename;	/* Name of binary as seen by procps */
55	const char * interp;	/* Name of the binary really executed. Most
56				   of the time same as filename, but could be
57				   different for binfmt_{misc,script} */
58	unsigned interp_flags;
59	unsigned interp_data;
60	unsigned long loader, exec;
61	char tcomm[TASK_COMM_LEN];
62};
63
64#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
65#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
66
67/* fd of the binary should be passed to the interpreter */
68#define BINPRM_FLAGS_EXECFD_BIT 1
69#define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
70
71#define BINPRM_MAX_RECURSION 4
72
73/* Function parameter for binfmt->coredump */
74struct coredump_params {
75	long signr;
76	struct pt_regs *regs;
77	struct file *file;
78	unsigned long limit;
79	unsigned long mm_flags;
80};
81
82/*
83 * This structure defines the functions that are used to load the binary formats that
84 * linux accepts.
85 */
86struct linux_binfmt {
87	struct list_head lh;
88	struct module *module;
89	int (*load_binary)(struct linux_binprm *, struct  pt_regs * regs);
90	int (*load_shlib)(struct file *);
91	int (*core_dump)(struct coredump_params *cprm);
92	unsigned long min_coredump;	/* minimal dump size */
93};
94
95extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
96
97/* Registration of default binfmt handlers */
98static inline void register_binfmt(struct linux_binfmt *fmt)
99{
100	__register_binfmt(fmt, 0);
101}
102/* Same as above, but adds a new binfmt at the top of the list */
103static inline void insert_binfmt(struct linux_binfmt *fmt)
104{
105	__register_binfmt(fmt, 1);
106}
107
108extern void unregister_binfmt(struct linux_binfmt *);
109
110extern int prepare_binprm(struct linux_binprm *);
111extern int __must_check remove_arg_zero(struct linux_binprm *);
112extern int search_binary_handler(struct linux_binprm *, struct pt_regs *);
113extern int flush_old_exec(struct linux_binprm * bprm);
114extern void setup_new_exec(struct linux_binprm * bprm);
115extern void would_dump(struct linux_binprm *, struct file *);
116
117extern int suid_dumpable;
118#define SUID_DUMP_DISABLE	0	/* No setuid dumping */
119#define SUID_DUMP_USER		1	/* Dump as user of process */
120#define SUID_DUMP_ROOT		2	/* Dump as root */
121
122/* Stack area protections */
123#define EXSTACK_DEFAULT   0	/* Whatever the arch defaults to */
124#define EXSTACK_DISABLE_X 1	/* Disable executable stacks */
125#define EXSTACK_ENABLE_X  2	/* Enable executable stacks */
126
127extern int setup_arg_pages(struct linux_binprm * bprm,
128			   unsigned long stack_top,
129			   int executable_stack);
130extern int bprm_mm_init(struct linux_binprm *bprm);
131extern int copy_strings_kernel(int argc, const char *const *argv,
132			       struct linux_binprm *bprm);
133extern int prepare_bprm_creds(struct linux_binprm *bprm);
134extern void install_exec_creds(struct linux_binprm *bprm);
135extern void do_coredump(long signr, int exit_code, struct pt_regs *regs);
136extern void set_binfmt(struct linux_binfmt *new);
137extern void free_bprm(struct linux_binprm *);
138
139#endif /* __KERNEL__ */
140#endif /* _LINUX_BINFMTS_H */
141