ceph/src/mds/MDSAuthCaps.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2014 Red Hat
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15
  16 #ifndef MDS_AUTH_CAPS_H
  17 #define MDS_AUTH_CAPS_H
  18
  19 #include <vector>
  20 #include <string>
  21 #include <sstream>
  22 #include "include/types.h"
  23 #include "common/debug.h"
  24
  25 // unix-style capabilities
  26 enum {
  27   MAY_READ = 1,
  28   MAY_WRITE = 2,
  29   MAY_EXECUTE = 4,
  30   MAY_CHOWN = 16,
  31   MAY_CHGRP = 32,
  32   MAY_SET_VXATTR = 64,
  33 };
  34
  35 class CephContext;
  36
  37 // what we can do
  38 struct MDSCapSpec {
  39   bool read, write, any;
  40
  41   // True if the capability permits setting vxattrs (layout, quota, etc)
  42   bool set_vxattr;
  43
  44   MDSCapSpec() : read(false), write(false), any(false), set_vxattr(false) {}
  45   MDSCapSpec(bool r, bool w, bool a, bool lop)
  46     : read(r), write(w), any(a), set_vxattr(lop) {}
  47
  48   bool allow_all() const {
  49     return any;
  50   }
  51
  52   bool allows(bool r, bool w) const {
  53     if (any)
  54       return true;
  55     if (r && !read)
  56       return false;
  57     if (w && !write)
  58       return false;
  59     return true;
  60   }
  61
  62   bool allows_set_vxattr() const {
  63     return set_vxattr;
  64   }
  65 };
  66
  67 // conditions before we are allowed to do it
  68 struct MDSCapMatch {
  69   static const int64_t MDS_AUTH_UID_ANY = -1;
  70
  71   int64_t uid;       // Require UID to be equal to this, if !=MDS_AUTH_UID_ANY
  72   std::vector<gid_t> gids;  // Use these GIDs
  73   std::string path;  // Require path to be child of this (may be "" or "/" for any)
  74
  75   MDSCapMatch() : uid(MDS_AUTH_UID_ANY) {}
  76   MDSCapMatch(int64_t uid_, std::vector<gid_t>& gids_) : uid(uid_), gids(gids_) {}
  77   explicit MDSCapMatch(std::string path_)
  78     : uid(MDS_AUTH_UID_ANY), path(path_) {
  79     normalize_path();
  80   }
  81   MDSCapMatch(std::string path_, int64_t uid_, std::vector<gid_t>& gids_)
  82     : uid(uid_), gids(gids_), path(path_) {
  83     normalize_path();
  84   }
  85
  86   void normalize_path();
  87
  88   bool is_match_all() const
  89   {
  90     return uid == MDS_AUTH_UID_ANY && path == "";
  91   }
  92
  93   // check whether this grant matches against a given file and caller uid:gid
  94   bool match(const std::string &target_path,
  95              const int caller_uid,
  96              const int caller_gid,
  97              const vector<uint64_t> *caller_gid_list) const;
  98
  99   /**
 100    * Check whether this path *might* be accessible (actual permission
 101    * depends on the stronger check in match()).
 102    *
 103    * @param target_path filesystem path without leading '/'
 104    */
 105   bool match_path(const std::string &target_path) const;
 106 };
 107
 108 struct MDSCapGrant {
 109   MDSCapSpec spec;
 110   MDSCapMatch match;
 111
 112   MDSCapGrant(const MDSCapSpec &spec_, const MDSCapMatch &match_)
 113     : spec(spec_), match(match_) {}
 114   MDSCapGrant() {}
 115 };
 116
 117 class MDSAuthCaps
 118 {
 119   CephContext *cct;
 120   std::vector<MDSCapGrant> grants;
 121
 122 public:
 123   explicit MDSAuthCaps(CephContext *cct_=NULL)
 124     : cct(cct_) { }
 125
 126   // this ctor is used by spirit/phoenix; doesn't need cct.
 127   explicit MDSAuthCaps(const std::vector<MDSCapGrant> &grants_)
 128     : cct(NULL), grants(grants_) { }
 129
 130   void set_allow_all();
 131   bool parse(CephContext *cct, const std::string &str, std::ostream *err);
 132
 133   bool allow_all() const;
 134   bool is_capable(const std::string &inode_path,
 135                   uid_t inode_uid, gid_t inode_gid, unsigned inode_mode,
 136                   uid_t uid, gid_t gid, const vector<uint64_t> *caller_gid_list,
 137                   unsigned mask, uid_t new_uid, gid_t new_gid) const;
 138   bool path_capable(const std::string &inode_path) const;
 139
 140   friend std::ostream &operator<<(std::ostream &out, const MDSAuthCaps &cap);
 141 };
 142
 143
 144 std::ostream &operator<<(std::ostream &out, const MDSCapMatch &match);
 145 std::ostream &operator<<(std::ostream &out, const MDSCapSpec &spec);
 146 std::ostream &operator<<(std::ostream &out, const MDSCapGrant &grant);
 147 std::ostream &operator<<(std::ostream &out, const MDSAuthCaps &cap);
 148
 149 #endif // MDS_AUTH_CAPS_H