kernel/bpf/test_stub.c

   1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of version 2 of the GNU General Public
   5  * License as published by the Free Software Foundation.
   6  */
   7 #include <linux/kernel.h>
   8 #include <linux/types.h>
   9 #include <linux/slab.h>
  10 #include <linux/err.h>
  11 #include <linux/bpf.h>
  12
  13 /* test stubs for BPF_MAP_TYPE_UNSPEC and for BPF_PROG_TYPE_UNSPEC
  14  * to be used by user space verifier testsuite
  15  */
  16 struct bpf_context {
  17         u64 arg1;
  18         u64 arg2;
  19 };
  20
  21 static const struct bpf_func_proto *test_func_proto(enum bpf_func_id func_id)
  22 {
  23         switch (func_id) {
  24         case BPF_FUNC_map_lookup_elem:
  25                 return &bpf_map_lookup_elem_proto;
  26         case BPF_FUNC_map_update_elem:
  27                 return &bpf_map_update_elem_proto;
  28         case BPF_FUNC_map_delete_elem:
  29                 return &bpf_map_delete_elem_proto;
  30         default:
  31                 return NULL;
  32         }
  33 }
  34
  35 static const struct bpf_context_access {
  36         int size;
  37         enum bpf_access_type type;
  38 } test_ctx_access[] = {
  39         [offsetof(struct bpf_context, arg1)] = {
  40                 FIELD_SIZEOF(struct bpf_context, arg1),
  41                 BPF_READ
  42         },
  43         [offsetof(struct bpf_context, arg2)] = {
  44                 FIELD_SIZEOF(struct bpf_context, arg2),
  45                 BPF_READ
  46         },
  47 };
  48
  49 static bool test_is_valid_access(int off, int size, enum bpf_access_type type)
  50 {
  51         const struct bpf_context_access *access;
  52
  53         if (off < 0 || off >= ARRAY_SIZE(test_ctx_access))
  54                 return false;
  55
  56         access = &test_ctx_access[off];
  57         if (access->size == size && (access->type & type))
  58                 return true;
  59
  60         return false;
  61 }
  62
  63 static struct bpf_verifier_ops test_ops = {
  64         .get_func_proto = test_func_proto,
  65         .is_valid_access = test_is_valid_access,
  66 };
  67
  68 static struct bpf_prog_type_list tl_prog = {
  69         .ops = &test_ops,
  70         .type = BPF_PROG_TYPE_UNSPEC,
  71 };
  72
  73 static int __init register_test_ops(void)
  74 {
  75         bpf_register_prog_type(&tl_prog);
  76         return 0;
  77 }
  78 late_initcall(register_test_ops);