winix can drop privileges now (if started as the root)

added parameters to the config:
 user (string)
 group (string)
 additional_groups (bool)



git-svn-id: svn://ttmath.org/publicrep/winix/trunk@668 e52654a7-88a9-db11-a3e9-0013d4bc506e

core/app.cpp

@@ -7,6 +7,11 @@
  * 
  */
  
+#include <sys/types.h>
+#include <pwd.h>
+#include <grp.h>
+#include <unistd.h>
+
 #include "app.h"
 #include "plugin.h"
 #include "misc.h"
@@ -138,7 +143,7 @@ bool App::Init()
 	db.LogQueries(config.log_db_query);
 
 	if( !CreateFCGISocket() )
-		return false;
+		return false; // !! dodac logsave do logow
 
 	request.Clear();
 	compress.Init();
@@ -148,7 +153,7 @@ bool App::Init()
 	// !! teraz mamy dwa katalogi z templetami
 	// !! o co chodzilo?
 	if( !notify.Init() )
-		return false;
+		return false; // !! dodac logsave do logow
 
 	// call this after system.Init() (mount points identificators should be created)
 	templates_notify.SetMountTypes(	system.mounts.MountTypeCms(),
@@ -714,3 +719,211 @@ Error status     = request.status;
 		FilterCompressSend(compressing, source);
 	}
 }
+
+
+void App::LogUser(const char * msg, uid_t id)
+{
+	log << log3 << msg << " ";
+
+	passwd * p = getpwuid(id);
+	
+	if( p )
+		log << p->pw_name;
+	else
+		log << id;
+
+	log << logend;
+}
+
+
+void App::LogGroup(const char * msg, gid_t id, bool put_logend)
+{
+	log << log3 << msg << " ";
+
+	group * g = getgrgid(id);
+
+	if( g )
+		log << g->gr_name;
+	else
+		log << (int)id;
+
+	if( put_logend )
+		log << logend;
+}
+
+
+void App::LogUsers()
+{
+uid_t eid, rid;
+	
+	eid = geteuid();
+	rid = getuid();
+
+	if( eid == rid )
+	{
+		LogUser("App: effective/real user:", eid);
+	}
+	else
+	{
+		LogUser("App: effective user:", eid);
+		LogUser("App: real user:",      rid);
+	}
+}
+
+
+
+void App::LogEffectiveGroups(std::vector<gid_t> & tab)
+{
+	log << log3 << "App: effective groups:";
+
+	for(size_t i=0 ; i<tab.size() ; ++i)
+	{
+		bool was_printed = false;
+
+		for(size_t x=0 ; x<i ; ++x)
+		{
+			if( tab[i] == tab[x] )
+			{
+				was_printed = true;
+				break;
+			}
+		}
+
+		if( !was_printed )
+			LogGroup("", tab[i], false);
+	}
+
+	log << logend;
+}
+
+
+void App::LogGroups()
+{
+std::vector<gid_t> tab;
+gid_t rgid;
+int len;
+
+	rgid = getgid(); 
+	len  = getgroups(0, 0);
+
+	if( len <= 0 )
+	{
+		log << log3 << "App: I can't read how many groups there are" << logend;
+		return;
+	}
+
+	tab.resize(len);
+	len = getgroups(len, &(tab[0]));
+
+	if( len == -1 )
+	{
+		log << log3 << "App: I can't read groups" << logend;
+		return;
+	}
+
+	if( len == 1 && rgid == tab[0] )
+	{
+		LogGroup("App: effective/real group:", rgid);
+	}
+	else
+	{
+		tab.resize(len);
+		LogEffectiveGroups(tab);
+		LogGroup("App: real group:", rgid);
+	}
+}
+
+
+void App::LogUserGroups()
+{
+	LogUsers();
+	LogGroups();
+}
+
+
+
+bool App::DropPrivileges(const std::string & user, uid_t uid, gid_t gid, bool additional_groups)
+{
+	if( additional_groups )
+	{
+		if( initgroups(user.c_str(), gid) < 0 )
+		{
+			log << log1 << "App: I can't init groups for user: " << user << logend << logsave;
+			return false;
+		}
+	}
+	else
+	{
+		if( setgroups(1, &gid) < 0 )
+		{
+			log << log1 << "App: I can't init groups for user: " << user << logend << logsave;
+			return false;
+		}
+	}
+
+	// for setting real and saved gid too
+	if( setgid(gid) )
+	{
+		log << log1 << "App: I can't change real and saved gid" << logend << logsave;
+		return false;
+	}
+
+	if( setuid(uid) < 0 )
+	{	
+		log << log1 << "App: I can't drop privileges to user: " << user
+			<< " (uid:" << uid << ")" << logend << logsave;
+		return false;
+	}
+
+	if( getuid()==0 || geteuid()==0 )
+	{
+		log << log1 << "App: sorry, for security reasons you should not run me as the root" << logend << logsave;
+		return false;
+	}
+
+return true;
+}
+
+
+bool App::DropPrivileges()
+{
+	if( getuid()!=0 && geteuid()!=0 )
+		return true;
+
+	log << log2 << "App: dropping privileges" << logend;
+
+	if( config.user.empty() )
+	{
+		log << log1 << "App: you should specify user name in the config file "
+					<< "to which I have to drop privileges" << logend << logsave;
+		return false;
+	}
+
+	if( config.group.empty() )
+	{
+		log << log1 << "App: you should specify group name in the config file "
+					<< "to which I have to drop privileges" << logend << logsave;
+		return false;
+	}
+
+	passwd * p = getpwnam(config.user.c_str());
+	group * g  = getgrnam(config.group.c_str());
+
+	if( !p )
+	{	
+		log << log1 << "App: there is no such a user as: \"" << config.user << "\"" << logend << logsave;
+		return false;
+	}
+
+	if( !g )
+	{	
+		log << log1 << "App: there is no such a group as: \"" << config.group << "\"" << logend << logsave;
+		return false;
+	}
+
+	if( !DropPrivileges(config.user, p->pw_uid, g->gr_gid, config.additional_groups) )
+		return false;
+
+return true;
+}
+