sandbox.h 4.8 KB

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  1. /* Copyright (c) 2001 Matej Pfajfar.
  2. * Copyright (c) 2001-2004, Roger Dingledine.
  3. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
  4. * Copyright (c) 2007-2017, The Tor Project, Inc. */
  5. /* See LICENSE for licensing information */
  6. /**
  7. * \file sandbox.h
  8. * \brief Header file for sandbox.c.
  9. **/
  10. #ifndef SANDBOX_H_
  11. #define SANDBOX_H_
  12. #include "orconfig.h"
  13. #include "torint.h"
  14. #ifndef SYS_SECCOMP
  15. /**
  16. * Used by SIGSYS signal handler to check if the signal was issued due to a
  17. * seccomp2 filter violation.
  18. */
  19. #define SYS_SECCOMP 1
  20. #endif /* !defined(SYS_SECCOMP) */
  21. #if defined(HAVE_SECCOMP_H) && defined(__linux__)
  22. #define USE_LIBSECCOMP
  23. #endif
  24. struct sandbox_cfg_elem;
  25. /** Typedef to structure used to manage a sandbox configuration. */
  26. typedef struct sandbox_cfg_elem sandbox_cfg_t;
  27. /**
  28. * Linux definitions
  29. */
  30. #ifdef USE_LIBSECCOMP
  31. #include <sys/ucontext.h>
  32. #include <seccomp.h>
  33. #include <netdb.h>
  34. #define PARAM_PTR 0
  35. #define PARAM_NUM 1
  36. /**
  37. * Enum used to manage the type of the implementation for general purpose.
  38. */
  39. typedef enum {
  40. /** Libseccomp implementation based on seccomp2*/
  41. LIBSECCOMP2 = 0
  42. } SB_IMPL;
  43. /**
  44. * Configuration parameter structure associated with the LIBSECCOMP2
  45. * implementation.
  46. */
  47. typedef struct smp_param {
  48. /** syscall associated with parameter. */
  49. int syscall;
  50. /** parameter value. */
  51. char *value;
  52. /** parameter value, second argument. */
  53. char *value2;
  54. /** parameter flag (0 = not protected, 1 = protected). */
  55. int prot;
  56. } smp_param_t;
  57. /**
  58. * Structure used to manage a sandbox configuration.
  59. *
  60. * It is implemented as a linked list of parameters. Currently only controls
  61. * parameters for open, openat, execve, stat64.
  62. */
  63. struct sandbox_cfg_elem {
  64. /** Sandbox implementation which dictates the parameter type. */
  65. SB_IMPL implem;
  66. /** Configuration parameter. */
  67. smp_param_t *param;
  68. /** Next element of the configuration*/
  69. struct sandbox_cfg_elem *next;
  70. };
  71. /** Function pointer defining the prototype of a filter function.*/
  72. typedef int (*sandbox_filter_func_t)(scmp_filter_ctx ctx,
  73. sandbox_cfg_t *filter);
  74. /** Type that will be used in step 3 in order to manage multiple sandboxes.*/
  75. typedef struct {
  76. /** function pointers associated with the filter */
  77. sandbox_filter_func_t *filter_func;
  78. /** filter function pointer parameters */
  79. sandbox_cfg_t *filter_dynamic;
  80. } sandbox_t;
  81. #endif /* defined(USE_LIBSECCOMP) */
  82. #ifdef USE_LIBSECCOMP
  83. /** Pre-calls getaddrinfo in order to pre-record result. */
  84. int sandbox_add_addrinfo(const char *addr);
  85. struct addrinfo;
  86. /** Replacement for getaddrinfo(), using pre-recorded results. */
  87. int sandbox_getaddrinfo(const char *name, const char *servname,
  88. const struct addrinfo *hints,
  89. struct addrinfo **res);
  90. void sandbox_freeaddrinfo(struct addrinfo *addrinfo);
  91. void sandbox_free_getaddrinfo_cache(void);
  92. #else /* !(defined(USE_LIBSECCOMP)) */
  93. #define sandbox_getaddrinfo(name, servname, hints, res) \
  94. getaddrinfo((name),(servname), (hints),(res))
  95. #define sandbox_add_addrinfo(name) \
  96. ((void)(name))
  97. #define sandbox_freeaddrinfo(addrinfo) \
  98. freeaddrinfo((addrinfo))
  99. #define sandbox_free_getaddrinfo_cache()
  100. #endif /* defined(USE_LIBSECCOMP) */
  101. #ifdef USE_LIBSECCOMP
  102. /** Returns a registered protected string used with the sandbox, given that
  103. * it matches the parameter.
  104. */
  105. const char* sandbox_intern_string(const char *param);
  106. #else /* !(defined(USE_LIBSECCOMP)) */
  107. #define sandbox_intern_string(s) (s)
  108. #endif /* defined(USE_LIBSECCOMP) */
  109. /** Creates an empty sandbox configuration file.*/
  110. sandbox_cfg_t * sandbox_cfg_new(void);
  111. /**
  112. * Function used to add a open allowed filename to a supplied configuration.
  113. * The (char*) specifies the path to the allowed file; we take ownership
  114. * of the pointer.
  115. */
  116. int sandbox_cfg_allow_open_filename(sandbox_cfg_t **cfg, char *file);
  117. int sandbox_cfg_allow_chmod_filename(sandbox_cfg_t **cfg, char *file);
  118. int sandbox_cfg_allow_chown_filename(sandbox_cfg_t **cfg, char *file);
  119. /* DOCDOC */
  120. int sandbox_cfg_allow_rename(sandbox_cfg_t **cfg, char *file1, char *file2);
  121. /**
  122. * Function used to add a openat allowed filename to a supplied configuration.
  123. * The (char*) specifies the path to the allowed file; we steal the pointer to
  124. * that file.
  125. */
  126. int sandbox_cfg_allow_openat_filename(sandbox_cfg_t **cfg, char *file);
  127. /**
  128. * Function used to add a stat/stat64 allowed filename to a configuration.
  129. * The (char*) specifies the path to the allowed file; that pointer is stolen.
  130. */
  131. int sandbox_cfg_allow_stat_filename(sandbox_cfg_t **cfg, char *file);
  132. /** Function used to initialise a sandbox configuration.*/
  133. int sandbox_init(sandbox_cfg_t* cfg);
  134. /** Return true iff the sandbox is turned on. */
  135. int sandbox_is_active(void);
  136. void sandbox_disable_getaddrinfo_cache(void);
  137. #endif /* !defined(SANDBOX_H_) */