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
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  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         // This is a "retain", matched by the deallocate call in ~Process
  73         mTaskPort.modRefs(MACH_PORT_RIGHT_SEND, 1);
  74
  75     // NB: ServerChild::find() should only be used to determine
  76     // *existence*.  Don't use the returned Child object for anything else,
  77     // as it is not protected against its underlying process's destruction.
  78         if (this->pid() == getpid() // called ourselves (through some API). Do NOT record this as a "dirty" transaction
  79         || ServerChild::find<ServerChild>(this->pid()))   // securityd's child; do not mark this txn dirty
  80         xpc_transaction_end();
  81
  82     secinfo("SecServer", "%p client new: pid:%d session:%d %s taskPort:%d uid:%d gid:%d", this, this->pid(), this->session().sessionId(),
  83              (char *)codePath(this->processCode()).c_str(), taskPort.port(), mUid, mGid);
  84 }
  85
  86
  87 //
  88 // Screen a process setup request for an existing process.
  89 // This means the client has requested intialization even though we remember having
  90 // talked to it in the past. This could either be an exec(2), or the client could just
  91 // have forgotten all about its securityd client state. Or it could be an attack...
  92 //
  93 void Process::reset(TaskPort taskPort, const ClientSetupInfo *info, const CommonCriteria::AuditToken &audit)
  94 {
  95         StLock<Mutex> _(*this);
  96         if (taskPort != mTaskPort) {
  97                 secnotice("SecServer", "Process %p(%d) reset mismatch (tp %d-%d)",
  98                         this, pid(), taskPort.port(), mTaskPort.port());
  99                 //@@@ CssmError::throwMe(CSSM_ERRCODE_VERIFICATION_FAILURE);            // liar
 100         }
 101         setup(info);
 102         CFCopyRef<SecCodeRef> oldCode = processCode();
 103
 104         ClientIdentification::setup(this->audit_token());       // re-constructs processCode()
 105         if (CFEqual(oldCode, processCode())) {
 106         secnotice("SecServer", "%p Client reset amnesia", this);
 107         } else {
 108         secnotice("SecServer", "%p Client reset full", this);
 109         }
 110 }
 111
 112
 113 //
 114 // Common set processing
 115 //
 116 void Process::setup(const ClientSetupInfo *info)
 117 {
 118         // process setup info
 119         assert(info);
 120         uint32 pversion;
 121         if (info->order == 0x1234) {    // right side up
 122                 pversion = info->version;
 123                 mByteFlipped = false;
 124         } else if (info->order == 0x34120000) { // flip side up
 125                 pversion = flip(info->version);
 126                 mByteFlipped = true;
 127         } else // non comprende
 128                 CssmError::throwMe(CSSM_ERRCODE_INCOMPATIBLE_VERSION);
 129
 130         // check wire protocol version
 131         if (pversion != SSPROTOVERSION)
 132                 CssmError::throwMe(CSSM_ERRCODE_INCOMPATIBLE_VERSION);
 133 }
 134
 135
 136 //
 137 // Clean up a Process object
 138 //
 139 Process::~Process()
 140 {
 141     secinfo("SecServer", "%p client release: %d", this, this->pid());
 142
 143     // release our name for the process's task port
 144     if (mTaskPort) {
 145         mTaskPort.deallocate();
 146     }
 147     xpc_transaction_end();
 148 }
 149
 150 void Process::kill()
 151 {
 152         StLock<Mutex> _(*this);
 153
 154         // release local temp store
 155         mLocalStore = NULL;
 156
 157         // standard kill processing
 158         PerProcess::kill();
 159 }
 160
 161
 162 Session& Process::session() const
 163 {
 164         return parent<Session>();
 165 }
 166
 167
 168 void Process::checkSession(const audit_token_t &auditToken)
 169 {
 170         Security::CommonCriteria::AuditToken audit(auditToken);
 171         if (audit.sessionId() != this->session().sessionId())
 172                 this->changeSession(audit.sessionId());
 173 }
 174
 175
 176 LocalDatabase &Process::localStore()
 177 {
 178         StLock<Mutex> _(*this);
 179         if (!mLocalStore)
 180                 mLocalStore = new TempDatabase(*this);
 181         return *mLocalStore;
 182 }
 183
 184 Key *Process::makeTemporaryKey(const CssmKey &key, CSSM_KEYATTR_FLAGS moreAttributes,
 185         const AclEntryPrototype *owner)
 186 {
 187         return safer_cast<TempDatabase&>(localStore()).makeKey(key, moreAttributes, owner);
 188 }
 189
 190
 191 //
 192 // Change the session of a process.
 193 // This is the result of SessionCreate from a known process client.
 194 //
 195 void Process::changeSession(Session::SessionId sessionId)
 196 {
 197         // re-parent
 198         parent(Session::find(sessionId, true));
 199     secnotice("SecServer", "%p client change session to %d", this, this->session().sessionId());
 200 }
 201
 202
 203 //
 204 // Debug dump support
 205 //
 206 #if defined(DEBUGDUMP)
 207
 208 void Process::dumpNode()
 209 {
 210         PerProcess::dumpNode();
 211         if (mByteFlipped)
 212                 Debug::dump(" FLIPPED");
 213         Debug::dump(" task=%d pid=%d uid/gid=%d/%d",
 214                 mTaskPort.port(), mPid, mUid, mGid);
 215         ClientIdentification::dump();
 216 }
 217
 218 #endif //DEBUGDUMP