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 long argmin; /* rlimit marker for copy_strings() */
  29        unsigned int
  30                /*
  31                 * True after the bprm_set_creds hook has been called once
  32                 * (multiple calls can be made via prepare_binprm() for
  33                 * binfmt_script/misc).
  34                 */
  35                called_set_creds:1,
  36                /*
  37                 * True if most recent call to the commoncaps bprm_set_creds
  38                 * hook (due to multiple prepare_binprm() calls from the
  39                 * binfmt_script/misc handlers) resulted in elevated
  40                 * privileges.
  41                 */
  42                cap_elevated:1,
  43                /*
  44                 * Set by bprm_set_creds hook to indicate a privilege-gaining
  45                 * exec has happened. Used to sanitize execution environment
  46                 * and to set AT_SECURE auxv for glibc.
  47                 */
  48                secureexec:1;
  49#ifdef __alpha__
  50        unsigned int taso:1;
  51#endif
  52        unsigned int recursion_depth; /* only for search_binary_handler() */
  53        struct file * file;
  54        struct cred *cred;      /* new credentials */
  55        int unsafe;             /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
  56        unsigned int per_clear; /* bits to clear in current->personality */
  57        int argc, envc;
  58        const char * filename;  /* Name of binary as seen by procps */
  59        const char * interp;    /* Name of the binary really executed. Most
  60                                   of the time same as filename, but could be
  61                                   different for binfmt_{misc,script} */
  62        unsigned interp_flags;
  63        unsigned interp_data;
  64        unsigned long loader, exec;
  65
  66        struct rlimit rlim_stack; /* Saved RLIMIT_STACK used during exec. */
  67} __randomize_layout;
  68
  69#define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
  70#define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
  71
  72/* fd of the binary should be passed to the interpreter */
  73#define BINPRM_FLAGS_EXECFD_BIT 1
  74#define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
  75
  76/* filename of the binary will be inaccessible after exec */
  77#define BINPRM_FLAGS_PATH_INACCESSIBLE_BIT 2
  78#define BINPRM_FLAGS_PATH_INACCESSIBLE (1 << BINPRM_FLAGS_PATH_INACCESSIBLE_BIT)
  79
  80/* Function parameter for binfmt->coredump */
  81struct coredump_params {
  82        const kernel_siginfo_t *siginfo;
  83        struct pt_regs *regs;
  84        struct file *file;
  85        unsigned long limit;
  86        unsigned long mm_flags;
  87        loff_t written;
  88        loff_t pos;
  89};
  90
  91/*
  92 * This structure defines the functions that are used to load the binary formats that
  93 * linux accepts.
  94 */
  95struct linux_binfmt {
  96        struct list_head lh;
  97        struct module *module;
  98        int (*load_binary)(struct linux_binprm *);
  99        int (*load_shlib)(struct file *);
 100        int (*core_dump)(struct coredump_params *cprm);
 101        unsigned long min_coredump;     /* minimal dump size */
 102} __randomize_layout;
 103
 104extern void __register_binfmt(struct linux_binfmt *fmt, int insert);
 105
 106/* Registration of default binfmt handlers */
 107static inline void register_binfmt(struct linux_binfmt *fmt)
 108{
 109        __register_binfmt(fmt, 0);
 110}
 111/* Same as above, but adds a new binfmt at the top of the list */
 112static inline void insert_binfmt(struct linux_binfmt *fmt)
 113{
 114        __register_binfmt(fmt, 1);
 115}
 116
 117extern void unregister_binfmt(struct linux_binfmt *);
 118
 119extern int prepare_binprm(struct linux_binprm *);
 120extern int __must_check remove_arg_zero(struct linux_binprm *);
 121extern int search_binary_handler(struct linux_binprm *);
 122extern int flush_old_exec(struct linux_binprm * bprm);
 123extern void setup_new_exec(struct linux_binprm * bprm);
 124extern void finalize_exec(struct linux_binprm *bprm);
 125extern void would_dump(struct linux_binprm *, struct file *);
 126
 127extern int suid_dumpable;
 128
 129/* Stack area protections */
 130#define EXSTACK_DEFAULT   0     /* Whatever the arch defaults to */
 131#define EXSTACK_DISABLE_X 1     /* Disable executable stacks */
 132#define EXSTACK_ENABLE_X  2     /* Enable executable stacks */
 133
 134extern int setup_arg_pages(struct linux_binprm * bprm,
 135                           unsigned long stack_top,
 136                           int executable_stack);
 137extern int transfer_args_to_stack(struct linux_binprm *bprm,
 138                                  unsigned long *sp_location);
 139extern int bprm_change_interp(const char *interp, struct linux_binprm *bprm);
 140extern int copy_strings_kernel(int argc, const char *const *argv,
 141                               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);
 153int do_execve_file(struct file *file, void *__argv, void *__envp);
 154
 155#endif /* _LINUX_BINFMTS_H */
 156