include/linux/binfmts.h

   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/list.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 #else
  33 # define MAX_ARG_PAGES  32
  34         struct page *page[MAX_ARG_PAGES];
  35 #endif
  36         struct mm_struct *mm;
  37         unsigned long p; /* current top of mem */
  38         unsigned int
  39                 cred_prepared:1,/* true if creds already prepared (multiple
  40                                  * preps happen for interpreters) */
  41                 cap_effective:1;/* true if has elevated effective capabilities,
  42                                  * false if not; except for init which inherits
  43                                  * its parent's caps anyway */
  44 #ifdef __alpha__
  45         unsigned int taso:1;
  46 #endif
  47         unsigned int recursion_depth;
  48         struct file * file;
  49         struct cred *cred;      /* new credentials */
  50         int unsafe;             /* how unsafe this exec is (mask of LSM_UNSAFE_*) */
  51         unsigned int per_clear; /* bits to clear in current->personality */
  52         int argc, envc;
  53         char * filename;        /* Name of binary as seen by procps */
  54         char * interp;          /* Name of the binary really executed. Most
  55                                    of the time same as filename, but could be
  56                                    different for binfmt_{misc,script} */
  57         unsigned interp_flags;
  58         unsigned interp_data;
  59         unsigned long loader, exec;
  60 };
  61
  62 #define BINPRM_FLAGS_ENFORCE_NONDUMP_BIT 0
  63 #define BINPRM_FLAGS_ENFORCE_NONDUMP (1 << BINPRM_FLAGS_ENFORCE_NONDUMP_BIT)
  64
  65 /* fd of the binary should be passed to the interpreter */
  66 #define BINPRM_FLAGS_EXECFD_BIT 1
  67 #define BINPRM_FLAGS_EXECFD (1 << BINPRM_FLAGS_EXECFD_BIT)
  68
  69 #define BINPRM_MAX_RECURSION 4
  70
  71 /*
  72  * This structure defines the functions that are used to load the binary formats that
  73  * linux accepts.
  74  */
  75 struct linux_binfmt {
  76         struct list_head lh;
  77         struct module *module;
  78         int (*load_binary)(struct linux_binprm *, struct  pt_regs * regs);
  79         int (*load_shlib)(struct file *);
  80         int (*core_dump)(long signr, struct pt_regs *regs, struct file *file, unsigned long limit);
  81         unsigned long min_coredump;     /* minimal dump size */
  82         int hasvdso;
  83 };
  84
  85 extern int __register_binfmt(struct linux_binfmt *fmt, int insert);
  86
  87 /* Registration of default binfmt handlers */
  88 static inline int register_binfmt(struct linux_binfmt *fmt)
  89 {
  90         return __register_binfmt(fmt, 0);
  91 }
  92 /* Same as above, but adds a new binfmt at the top of the list */
  93 static inline int insert_binfmt(struct linux_binfmt *fmt)
  94 {
  95         return __register_binfmt(fmt, 1);
  96 }
  97
  98 extern void unregister_binfmt(struct linux_binfmt *);
  99
 100 extern int prepare_binprm(struct linux_binprm *);
 101 extern int __must_check remove_arg_zero(struct linux_binprm *);
 102 extern int search_binary_handler(struct linux_binprm *,struct pt_regs *);
 103 extern int flush_old_exec(struct linux_binprm * bprm);
 104
 105 extern int suid_dumpable;
 106 #define SUID_DUMP_DISABLE       0       /* No setuid dumping */
 107 #define SUID_DUMP_USER          1       /* Dump as user of process */
 108 #define SUID_DUMP_ROOT          2       /* Dump as root */
 109
 110 /* Stack area protections */
 111 #define EXSTACK_DEFAULT   0     /* Whatever the arch defaults to */
 112 #define EXSTACK_DISABLE_X 1     /* Disable executable stacks */
 113 #define EXSTACK_ENABLE_X  2     /* Enable executable stacks */
 114
 115 extern int setup_arg_pages(struct linux_binprm * bprm,
 116                            unsigned long stack_top,
 117                            int executable_stack);
 118 extern int bprm_mm_init(struct linux_binprm *bprm);
 119 extern int copy_strings_kernel(int argc,char ** argv,struct linux_binprm *bprm);
 120 extern void install_exec_creds(struct linux_binprm *bprm);
 121 extern void do_coredump(long signr, int exit_code, struct pt_regs *regs);
 122 extern int set_binfmt(struct linux_binfmt *new);
 123 extern void free_bprm(struct linux_binprm *);
 124
 125 #endif /* __KERNEL__ */
 126 #endif /* _LINUX_BINFMTS_H */