LXR linux/include/linux/binfmts.h

   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