1 #ifndef _LINUX_BINFMTS_H
2 #define _LINUX_BINFMTS_H
3
4 #include <linux/capability.h>
5
6 struct 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 */
28 struct 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 /* Function parameter for binfmt->coredump */
72 struct coredump_params {
73 long signr;
74 struct pt_regs *regs;
75 struct file *file;
76 unsigned long limit;
77 unsigned long mm_flags;
78 };
79
80 /*
81 * This structure defines the functions that are used to load the binary formats that
82 * linux accepts.
83 */
84 struct linux_binfmt {
85 struct list_head lh;
86 struct module *module;
87 int (*load_binary)(struct linux_binprm *, struct pt_regs * regs);
88 int (*load_shlib)(struct file *);
89 int (*core_dump)(struct coredump_params *cprm);
90 unsigned long min_coredump; /* minimal dump size */
91 };
92
93 extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
94
95 /* Registration of default binfmt handlers */
register_binfmt(struct linux_binfmt * fmt)96 static inline void register_binfmt(struct linux_binfmt *fmt)
97 {
98 __register_binfmt(fmt, 0);
99 }
100 /* Same as above, but adds a new binfmt at the top of the list */
insert_binfmt(struct linux_binfmt * fmt)101 static inline void insert_binfmt(struct linux_binfmt *fmt)
102 {
103 __register_binfmt(fmt, 1);
104 }
105
106 extern void unregister_binfmt(struct linux_binfmt *);
107
108 extern int prepare_binprm(struct linux_binprm *);
109 extern int __must_check remove_arg_zero(struct linux_binprm *);
110 extern int search_binary_handler(struct linux_binprm *, struct pt_regs *);
111 extern int flush_old_exec(struct linux_binprm * bprm);
112 extern void setup_new_exec(struct linux_binprm * bprm);
113 extern void would_dump(struct linux_binprm *, struct file *);
114
115 extern int suid_dumpable;
116
117 /* Stack area protections */
118 #define EXSTACK_DEFAULT 0 /* Whatever the arch defaults to */
119 #define EXSTACK_DISABLE_X 1 /* Disable executable stacks */
120 #define EXSTACK_ENABLE_X 2 /* Enable executable stacks */
121
122 extern int setup_arg_pages(struct linux_binprm * bprm,
123 unsigned long stack_top,
124 int executable_stack);
125 extern int bprm_mm_init(struct linux_binprm *bprm);
126 extern int bprm_change_interp(char *interp, struct linux_binprm *bprm);
127 extern int copy_strings_kernel(int argc, const char *const *argv,
128 struct linux_binprm *bprm);
129 extern int prepare_bprm_creds(struct linux_binprm *bprm);
130 extern void install_exec_creds(struct linux_binprm *bprm);
131 extern void do_coredump(long signr, int exit_code, struct pt_regs *regs);
132 extern void set_binfmt(struct linux_binfmt *new);
133 extern void free_bprm(struct linux_binprm *);
134
135 #endif /* __KERNEL__ */
136 #endif /* _LINUX_BINFMTS_H */
137