securityd/src/process.cpp

   1 /*
   2  * Copyright (c) 2000-2009,2012 Apple Inc. All Rights Reserved.
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   8  * Version 2.0 (the 'License'). You may not use this file except in
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  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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  23
  24
  25 //
  26 // process - track a single client process and its belongings
  27 //
  28 #include "process.h"
  29 #include "server.h"
  30 #include "session.h"
  31 #include "tempdatabase.h"
  32 #include "child.h"          // ServerChild (really UnixPlusPlus::Child)::find()
  33
  34 #include <security_utilities/ccaudit.h>
  35 #include <security_utilities/logging.h> //@@@ debug only
  36 #include "agentquery.h"
  37
  38
  39 //
  40 // Construct a Process object.
  41 //
  42 Process::Process(TaskPort taskPort,     const ClientSetupInfo *info, const CommonCriteria::AuditToken &audit)
  43  :  mTaskPort(taskPort), mByteFlipped(false), mPid(audit.pid()), mUid(audit.euid()), mGid(audit.egid()), mAudit(audit)
  44 {
  45         StLock<Mutex> _(*this);
  46     xpc_transaction_begin();
  47         // set parent session
  48         parent(Session::find(audit.sessionId(), true));
  49
  50         // let's take a look at our wannabe client...
  51
  52         // Not enough to make sure we will get the right process, as
  53         // pids get recycled. But we will later create the actual SecCode using
  54         // the audit token, which is unique to the one instance of the process,
  55         // so this just catches a pid mismatch early.
  56         if (mTaskPort.pid() != mPid) {
  57                 secnotice("SecServer", "Task/pid setup mismatch pid=%d task=%d(%d)",
  58                                   mPid, mTaskPort.port(), mTaskPort.pid());
  59                 CssmError::throwMe(CSSMERR_CSSM_ADDIN_AUTHENTICATE_FAILED);     // you lied!
  60         }
  61
  62         setup(info);
  63         ClientIdentification::setup(this->audit_token());
  64
  65         if(!processCode()) {
  66                 // This can happen if the process died in the meantime.
  67                 secnotice("SecServer", "no process created in setup, old pid=%d old task=%d(%d)",
  68                                   mPid, mTaskPort.port(), mTaskPort.pid());
  69                 CssmError::throwMe(CSSMERR_CSSM_ADDIN_AUTHENTICATE_FAILED);
  70         }
  71
  72     // NB: ServerChild::find() should only be used to determine
  73     // *existence*.  Don't use the returned Child object for anything else,
  74     // as it is not protected against its underlying process's destruction.
  75         if (this->pid() == getpid() // called ourselves (through some API). Do NOT record this as a "dirty" transaction
  76         || ServerChild::find<ServerChild>(this->pid()))   // securityd's child; do not mark this txn dirty
  77         xpc_transaction_end();
  78
  79     secinfo("SecServer", "%p client new: pid:%d session:%d %s taskPort:%d uid:%d gid:%d", this, this->pid(), this->session().sessionId(),
  80              (char *)codePath(this->processCode()).c_str(), taskPort.port(), mUid, mGid);
  81 }
  82
  83
  84 //
  85 // Screen a process setup request for an existing process.
  86 // This means the client has requested intialization even though we remember having
  87 // talked to it in the past. This could either be an exec(2), or the client could just
  88 // have forgotten all about its securityd client state. Or it could be an attack...
  89 //
  90 void Process::reset(TaskPort taskPort, const ClientSetupInfo *info, const CommonCriteria::AuditToken &audit)
  91 {
  92         StLock<Mutex> _(*this);
  93         if (taskPort != mTaskPort) {
  94                 secnotice("SecServer", "Process %p(%d) reset mismatch (tp %d-%d)",
  95                         this, pid(), taskPort.port(), mTaskPort.port());
  96                 //@@@ CssmError::throwMe(CSSM_ERRCODE_VERIFICATION_FAILURE);            // liar
  97         }
  98         setup(info);
  99         CFCopyRef<SecCodeRef> oldCode = processCode();
 100
 101         ClientIdentification::setup(this->audit_token());       // re-constructs processCode()
 102         if (CFEqual(oldCode, processCode())) {
 103         secnotice("SecServer", "%p Client reset amnesia", this);
 104         } else {
 105         secnotice("SecServer", "%p Client reset full", this);
 106         }
 107 }
 108
 109
 110 //
 111 // Common set processing
 112 //
 113 void Process::setup(const ClientSetupInfo *info)
 114 {
 115         // process setup info
 116         assert(info);
 117         uint32 pversion;
 118         if (info->order == 0x1234) {    // right side up
 119                 pversion = info->version;
 120                 mByteFlipped = false;
 121         } else if (info->order == 0x34120000) { // flip side up
 122                 pversion = flip(info->version);
 123                 mByteFlipped = true;
 124         } else // non comprende
 125                 CssmError::throwMe(CSSM_ERRCODE_INCOMPATIBLE_VERSION);
 126
 127         // check wire protocol version
 128         if (pversion != SSPROTOVERSION)
 129                 CssmError::throwMe(CSSM_ERRCODE_INCOMPATIBLE_VERSION);
 130 }
 131
 132
 133 //
 134 // Clean up a Process object
 135 //
 136 Process::~Process()
 137 {
 138     secinfo("SecServer", "%p client release: %d", this, this->pid());
 139
 140     // release our name for the process's task port
 141     if (mTaskPort) {
 142         mTaskPort.deallocate();
 143     }
 144     xpc_transaction_end();
 145 }
 146
 147 void Process::kill()
 148 {
 149         StLock<Mutex> _(*this);
 150
 151         // release local temp store
 152         mLocalStore = NULL;
 153
 154         // standard kill processing
 155         PerProcess::kill();
 156 }
 157
 158
 159 Session& Process::session() const
 160 {
 161         return parent<Session>();
 162 }
 163
 164
 165 void Process::checkSession(const audit_token_t &auditToken)
 166 {
 167         Security::CommonCriteria::AuditToken audit(auditToken);
 168         if (audit.sessionId() != this->session().sessionId())
 169                 this->changeSession(audit.sessionId());
 170 }
 171
 172
 173 LocalDatabase &Process::localStore()
 174 {
 175         StLock<Mutex> _(*this);
 176         if (!mLocalStore)
 177                 mLocalStore = new TempDatabase(*this);
 178         return *mLocalStore;
 179 }
 180
 181 Key *Process::makeTemporaryKey(const CssmKey &key, CSSM_KEYATTR_FLAGS moreAttributes,
 182         const AclEntryPrototype *owner)
 183 {
 184         return safer_cast<TempDatabase&>(localStore()).makeKey(key, moreAttributes, owner);
 185 }
 186
 187
 188 //
 189 // Change the session of a process.
 190 // This is the result of SessionCreate from a known process client.
 191 //
 192 void Process::changeSession(Session::SessionId sessionId)
 193 {
 194         // re-parent
 195         parent(Session::find(sessionId, true));
 196     secnotice("SecServer", "%p client change session to %d", this, this->session().sessionId());
 197 }
 198
 199
 200 //
 201 // Debug dump support
 202 //
 203 #if defined(DEBUGDUMP)
 204
 205 void Process::dumpNode()
 206 {
 207         PerProcess::dumpNode();
 208         if (mByteFlipped)
 209                 Debug::dump(" FLIPPED");
 210         Debug::dump(" task=%d pid=%d uid/gid=%d/%d",
 211                 mTaskPort.port(), mPid, mUid, mGid);
 212         ClientIdentification::dump();
 213 }
 214
 215 #endif //DEBUGDUMP