OSX/libsecurity_cdsa_utilities/lib/acl_process.cpp

   1 /*
   2  * Copyright (c) 2000-2004,2006,2011,2014 Apple Inc. All Rights Reserved.
   3  *
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   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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  18  * Please see the License for the specific language governing rights and
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  22  */
  23
  24
  25 //
  26 // acl_process - Process-attribute ACL subject type.
  27 //
  28 #include <security_cdsa_utilities/acl_process.h>
  29 #include <security_utilities/endian.h>
  30 #include <algorithm>
  31
  32
  33 //
  34 // Validate a credential set against this subject.
  35 // No credential is required for this match.
  36 //
  37 bool ProcessAclSubject::validates(const AclValidationContext &context) const
  38 {
  39     // reality check (internal structure was validated when created)
  40     assert(select.uses(CSSM_ACL_MATCH_BITS));
  41
  42     // access the environment
  43     Environment *env = context.environment<Environment>();
  44     if (env == NULL) {
  45         static Environment localEnvironment;
  46         env = &localEnvironment;
  47     }
  48
  49     // match uid
  50     if (select.uses(CSSM_ACL_MATCH_UID)) {
  51         uid_t uid = env->getuid();
  52         if (!(uid == select.uid || (select.uses(CSSM_ACL_MATCH_HONOR_ROOT) && uid == 0)))
  53             return false;
  54     }
  55
  56     // match gid
  57     if (select.uses(CSSM_ACL_MATCH_GID) && select.gid != env->getgid())
  58         return false;
  59
  60     return true;
  61 }
  62
  63
  64 //
  65 // Make a copy of this subject in CSSM_LIST form
  66 //
  67 CssmList ProcessAclSubject::toList(Allocator &alloc) const
  68 {
  69     // all associated data is public (no secrets)
  70     //@@@ ownership of selector data is murky; revisit after leak-plugging pass
  71     CssmData sData(memcpy(alloc.alloc<CSSM_ACL_PROCESS_SUBJECT_SELECTOR>(),
  72         &select, sizeof(select)), sizeof(select));
  73         return TypedList(alloc, CSSM_ACL_SUBJECT_TYPE_PROCESS,
  74         new(alloc) ListElement(sData));
  75 }
  76
  77
  78 //
  79 // Create a ProcessAclSubject
  80 //
  81 ProcessAclSubject *ProcessAclSubject::Maker::make(const TypedList &list) const
  82 {
  83     // crack input apart
  84         ListElement *selectorData;
  85         crack(list, 1, &selectorData, CSSM_LIST_ELEMENT_DATUM);
  86     AclProcessSubjectSelector selector;
  87     selectorData->extract(selector);
  88
  89     // validate input
  90     if (selector.version != CSSM_ACL_PROCESS_SELECTOR_CURRENT_VERSION)
  91         CssmError::throwMe(CSSM_ERRCODE_INVALID_ACL_SUBJECT_VALUE);
  92     if (!selector.uses(CSSM_ACL_MATCH_BITS))
  93         CssmError::throwMe(CSSM_ERRCODE_INVALID_ACL_SUBJECT_VALUE);
  94
  95     // okay
  96         return new ProcessAclSubject(selector);
  97 }
  98
  99 ProcessAclSubject *ProcessAclSubject::Maker::make(Version, Reader &pub, Reader &priv) const
 100 {
 101     AclProcessSubjectSelector selector; pub(selector);
 102         n2hi(selector.version);
 103         n2hi(selector.mask);
 104         n2hi(selector.uid);
 105         n2hi(selector.gid);
 106         return new ProcessAclSubject(selector);
 107 }
 108
 109
 110 //
 111 // Export the subject to a memory blob
 112 //
 113 void ProcessAclSubject::exportBlob(Writer::Counter &pub, Writer::Counter &priv)
 114 {
 115     pub(select);
 116 }
 117
 118 void ProcessAclSubject::exportBlob(Writer &pub, Writer &priv)
 119 {
 120         AclProcessSubjectSelector temp;
 121         temp.version = h2n (select.version);
 122         temp.mask = h2n (select.mask);
 123         temp.uid = h2n (select.uid);
 124         temp.gid = h2n (select.gid);
 125     pub(temp);
 126 }
 127
 128
 129 //
 130 // Implement the default methods of a ProcessEnvironment
 131 //
 132 uid_t ProcessAclSubject::Environment::getuid() const
 133 {
 134     return ::getuid();
 135 }
 136
 137 gid_t ProcessAclSubject::Environment::getgid() const
 138 {
 139     return ::getgid();
 140 }
 141
 142
 143 #ifdef DEBUGDUMP
 144
 145 void ProcessAclSubject::debugDump() const
 146 {
 147         Debug::dump("Process ");
 148         if (select.uses(CSSM_ACL_MATCH_UID)) {
 149                 Debug::dump("uid=%d", int(select.uid));
 150                 if (select.uses(CSSM_ACL_MATCH_HONOR_ROOT))
 151                         Debug::dump("+root");
 152         }
 153         if (select.uses(CSSM_ACL_MATCH_GID))
 154                 Debug::dump("gid=%d", int(select.gid));
 155 }
 156
 157 #endif //DEBUGDUMP