securityd-61.tar.gz

[apple/securityd.git] / src / authhost.cpp

diff --git a/src/authhost.cpp b/src/authhost.cpp
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--- /dev/null
+++ b/src/authhost.cpp
@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved.
+ * 
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+#include <paths.h>
+#include <fcntl.h>
+#include "authhost.h"
+#include "server.h"
+
+#include <grp.h>
+#include <pwd.h>
+
+
+AuthHostInstance::AuthHostInstance(Session &session, AuthHostType host) :
+       mHostType(host)
+{
+       secdebug("authhost", "authhost born (%p)", this);
+       referent(session);
+       session.addReference(*this);
+}
+
+AuthHostInstance::~AuthHostInstance()
+{ 
+       secdebug("authhost", "authhost died (%p)", this);
+       
+       // clean up
+       servicePort ().destroy ();
+}
+
+Session &AuthHostInstance::session() const
+{
+       return referent<Session>();
+}
+
+void
+AuthHostInstance::childAction()
+{
+       // Setup the environment for the SecurityAgent
+       unsetenv("USER");
+       unsetenv("LOGNAME");
+       unsetenv("HOME");
+                               
+       // close down any files that might have been open at this point
+       int maxDescriptors = getdtablesize ();
+       int i;
+       
+       int devnull = open(_PATH_DEVNULL, O_RDWR, 0);
+       if (devnull >= 0) for (i = 0; i < 3; ++i)
+       {
+               dup2(devnull, i);
+       }
+       
+       for (i = 3; i < maxDescriptors; ++i)
+       {
+               close (i);
+       }
+       
+       // construct path to SecurityAgent
+       char agentExecutable[PATH_MAX + 1];
+       const char *path = getenv("SECURITYAGENT");
+       if (!path)
+               path = "/System/Library/CoreServices/SecurityAgent.app";
+
+       if ((mHostType == userAuthHost) || (mHostType == privilegedAuthHost))
+       {
+               snprintf(agentExecutable, sizeof(agentExecutable), "%s/Contents/Resources/authorizationhost", path);
+       
+               secdebug("AuthHostInstance", "execl(%s)", agentExecutable);
+               execl(agentExecutable, agentExecutable, NULL);
+       }
+       else
+       {
+               snprintf(agentExecutable, sizeof(agentExecutable), "%s/Contents/MacOS/SecurityAgent", path);
+
+               struct group *agentGroup = getgrnam("securityagent");
+               gid_t agentGID = static_cast<gid_t>(-2);
+               if (agentGroup)
+               {
+                       agentGID = agentGroup->gr_gid;
+                       endgrent();
+               }
+
+               struct passwd *agentUser = getpwnam("securityagent");
+               uid_t agentUID = static_cast<uid_t>(-2);
+               if (agentUser)
+               {
+                       agentUID = agentUser->pw_uid;
+                       endpwent();
+               }
+
+               setuid(agentUID);
+               setgid(agentGID);
+       
+               CFRef<CFDataRef> userPrefs(session().copyUserPrefs());
+               
+               FILE *mbox = tmpfile();
+               
+               if (userPrefs && mbox)
+               {
+                       if (fwrite(CFDataGetBytePtr(userPrefs), CFDataGetLength(userPrefs), 1, mbox) != 1)
+                               fclose(mbox);
+                       else
+                       {
+                               char mboxFdString[20];
+                               fflush(mbox);
+                               if ((int)sizeof(mboxFdString) > snprintf(mboxFdString, sizeof(mboxFdString), "%d", fileno(mbox)))
+                                       setenv("SECURITYAGENT_USERPREFS_FD", mboxFdString, 1);
+                       }
+               }
+               
+               secdebug("AuthHostInstance", "execl(%s) as user (%d,%d)", agentExecutable, agentUID, agentGID);
+               execl(agentExecutable, agentExecutable, NULL);
+       }
+
+       secdebug("AuthHostInstance", "execl failed, errno=%d", errno);
+       // Unconditional suicide follows.
+       // See comments below on why we can't use abort()
+#if 1
+       _exit(1);
+#else
+       // NOTE: OS X abort() is implemented as kill(getuid()), which fails
+       // for a setuid-root process that has setuid'd. Go back to root to die...
+       setuid(0);
+       abort();
+#endif
+}
+
+Port
+AuthHostInstance::activate()
+{
+       StLock<Mutex> _(*this);
+       if (state() != alive)
+       {
+               if (!(session().attributes() & sessionHasGraphicAccess))
+                       CssmError::throwMe(CSSM_ERRCODE_NO_USER_INTERACTION);
+
+               Security::MachPlusPlus::StBootstrap bootSaver(session().bootstrapPort());
+
+               fork();
+               switch (ServerChild::state()) {
+               case Child::alive:
+                       secdebug("AuthHostInstance", "%p (pid %d) has launched", this, pid());
+                       break;
+               case Child::dead:
+                       secdebug("AuthHostInstance", "%p (pid %d) failed on startup", this, pid());
+                       break;
+               default:
+                       assert(false);
+               }
+       }
+
+       if (!ready())
+               CssmError::throwMe(CSSM_ERRCODE_NO_USER_INTERACTION);
+
+       return servicePort();
+}