LXR linux/include/linux/binfmts.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_BINFMTS_H
   3#define _LINUX_BINFMTS_H
   4
   5#include <linux/sched.h>
   6#include <linux/unistd.h>
   7#include <asm/exec.h>
   8#include <uapi/linux/binfmts.h>
   9
  10struct filename;
  11
  12#define CORENAME_MAX_SIZE 128
  13
  14/*
  15 * This structure is used to hold the arguments that are used when loading binaries.
  16 */
  17struct linux_binprm {
  18        char buf[BINPRM_BUF_SIZE];
  19#ifdef CONFIG_MMU
  20        struct vm_area_struct *vma;
  21        unsigned long vma_pages;
  22#else
  23# define MAX_ARG_PAGES  32
  24        struct page *page[MAX_ARG_PAGES];
  25#endif
  26        struct mm_struct *mm;
  27        unsigned long p; /* current top of mem */
  28        unsigned int
  29                /*
  30                 * True after the bprm_set_creds hook has been called once
  31                 * (multiple calls can be made via prepare_binprm() for
  32                 * binfmt_script/misc).
  33                 */
  34                called_set_creds:1,
  35                /*
  36                 * True if most recent call to the commoncaps bprm_set_creds
  37                 * hook (due to multiple prepare_binprm() calls from the
  38                 * binfmt_script/misc handlers) resulted in elevated
  39                 * privileges.
  40                 */
  41                cap_elevated:1,
  42                /*
  43                 * Set by bprm_set_creds hook to indicate a privilege-gaining
  44                 * exec has happened. Used to sanitize execution environment
  45                 * and to set AT_SECURE auxv for glibc.
  46                 */
  47                secureexec:1;
  48#ifdef __alpha__
  49        unsigned int taso:1;
  50#endif
  51        unsigned int recursion_depth; /* only for search_binary_handler() */
  52        struct file * file;
  53        struct cred *cred;      /* new credentials */
  54        int unsafe;             /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
  55        unsigned int per_clear; /* bits to clear in current->personality */
  56        int argc, envc;
  57        const char * filename;  /* Name of binary as seen by procps */
  58        const char * interp;    /* Name of the binary really executed. Most
  59                                   of the time same as filename, but could be
  60                                   different for binfmt_{misc,script} */
  61        unsigned interp_flags;
  62        unsigned interp_data;
  63        unsigned long loader, exec;
  64
  65        struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */
  66} __randomize_layout;
  67
  68#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
  69#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
  70
  71/* fd of the binary should be passed to the interpreter */
  72#define BINPRM_FLAGS_EXECFD_BIT 1
  73#define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
  74
  75/* filename of the binary will be inaccessible after exec */
  76#define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2
  77#define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT)
  78
  79/* Function parameter for binfmt->coredump */
  80struct coredump_params {
  81        const siginfo_t *siginfo;
  82        struct pt_regs *regs;
  83        struct file *file;
  84        unsigned long limit;
  85        unsigned long mm_flags;
  86        loff_t written;
  87        loff_t pos;
  88};
  89
  90/*
  91 * This structure defines the functions that are used to load the binary formats that
  92 * linux accepts.
  93 */
  94struct linux_binfmt {
  95        struct list_head lh;
  96        struct module *module;
  97        int (*load_binary)(struct linux_binprm *);
  98        int (*load_shlib)(struct file *);
  99        int (*core_dump)(struct coredump_params *cprm);
 100        unsigned long min_coredump;     /* minimal dump size */
 101} __randomize_layout;
 102
 103extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
 104
 105/* Registration of default binfmt handlers */
 106static inline void register_binfmt(struct linux_binfmt *fmt)
 107{
 108        __register_binfmt(fmt, 0);
 109}
 110/* Same as above, but adds a new binfmt at the top of the list */
 111static inline void insert_binfmt(struct linux_binfmt *fmt)
 112{
 113        __register_binfmt(fmt, 1);
 114}
 115
 116extern void unregister_binfmt(struct linux_binfmt *);
 117
 118extern int prepare_binprm(struct linux_binprm *);
 119extern int __must_check remove_arg_zero(struct linux_binprm *);
 120extern int search_binary_handler(struct linux_binprm *);
 121extern int flush_old_exec(struct linux_binprm * bprm);
 122extern void setup_new_exec(struct linux_binprm * bprm);
 123extern void finalize_exec(struct linux_binprm *bprm);
 124extern void would_dump(struct linux_binprm *, struct file *);
 125
 126extern int suid_dumpable;
 127
 128/* Stack area protections */
 129#define EXSTACK_DEFAULT   0     /* Whatever the arch defaults to */
 130#define EXSTACK_DISABLE_X 1     /* Disable executable stacks */
 131#define EXSTACK_ENABLE_X  2     /* Enable executable stacks */
 132
 133extern int setup_arg_pages(struct linux_binprm * bprm,
 134                           unsigned long stack_top,
 135                           int executable_stack);
 136extern int transfer_args_to_stack(struct linux_binprm *bprm,
 137                                  unsigned long *sp_location);
 138extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
 139extern int copy_strings_kernel(int argc, const char *const *argv,
 140                               struct linux_binprm *bprm);
 141extern int prepare_bprm_creds(struct linux_binprm *bprm);
 142extern void install_exec_creds(struct linux_binprm *bprm);
 143extern void set_binfmt(struct linux_binfmt *new);
 144extern ssize_t read_code(struct file *, unsigned long, loff_t, size_t);
 145
 146extern int do_execve(struct filename *,
 147                     const char __user * const __user *,
 148                     const char __user * const __user *);
 149extern int do_execveat(int, struct filename *,
 150                       const char __user * const __user *,
 151                       const char __user * const __user *,
 152                       int);
 153
 154#endif /* _LINUX_BINFMTS_H */
 155