aboutsummaryrefslogblamecommitdiffstats
path: root/lib/snmp/src/manager/snmpm_config.erl
blob: 2101ad46e1ee96f5094dfa871d8bc283be33761c (plain) (tree)
1
2
3
4
5
6
7
8
9
10
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686

                   
  
                                                        
  




                                                                      
  



                                                                         
  













                                                                            

                                                                           





                                                

                                                   



























                                                              
                                                   

















                                                      


                                   









































                                                              


                                                 




                                          

                                                          
 

                                                


                                           
                                              
                                                                              














                                                                      

                             
                           

 













































































































                                                                             
                                                                         
                                

                                                                   







                                                           


























                                                                               
                                                                          
                                   
                                            

                                         





                                                                  
 

                                                  
                                                                    
                          
                                                                
                                                                           

                                        





                                                               





                                                                    
                              
                                       
                                      



                      


                 


























                                                                    

                                                  
                                      


                                                  
                                               
















                                                                    






                                                 
                                                                    






















































                                                                         













                                                                      

                                                                      


                                                
                                                                        










                                                                              


                 










                                                               






                                                             
                       


















































































































































































































                                                                







                                                           
































































































































                                                                          



























                                                              




























































































































































































































                                                                               




                                                         


                                                                              

                                                                              

















































































                                                                             





                                                      




































































































                                                                           







                                                                           















































                                                                





                                                 












































































                                                                      
                                






                                                      


                                  




                                       

                                               



















































                                                            


                                                     









































                                                              




                                                  












































































































                                                                           
                             






                                                             
                                         





                                                 
                                                               



                                
                                       


                                                             



                                              
                                     








                                       

                                            

                                                    
                                          



                                                      
                                  
























                                                                          
                             






                                                       
                                         





                                     
                                                         







                                                       
                                        


                                                         








                                                     
                                      
















                                                     

        
                       


                                  

                                                    

                                  
                                                               


               
                                        














                                                                         



                                              
                                           
                                                               
                                                                    





                                                 

                                              
                                                                        
                                                                




                                                                        







































                                                                    


                                    




                                                                

                                                                
















                                                                








                                                                






































































































                                                                             
                                    







                                                                     
                                            







                                                                              
                                    







                                                                     
                                            

















                                                                              
                                        







                                                                 
                                                







                                                                          
                                           







                                                                   
                                                   








                                                                            

                                              
                            
                                         






































































































































































                                                                               









                                                               








                                                                    
                     








































































































































































































































































































































































                                                                             
                                                                                

                                                            



                                                                                 
                                                                    

                                                                         




                                                                         
                                                                           
                                                                 

                                                                              
                                                              
                                                                                   























                                                                        




                                                                  



                                                               


                                                                 

































                                                                          
                                                     


                                                    

                                                               
                                                   

                                                       





                                              







                                                        
                





                                                            

        






















                                                                        


































































                                                                         
                                    


                                                                        
                                              













                                                                         
                                    


                                                                        
                                              





























                                                                        
                                        


                                                                        
                                                  




                                                                        
                                           


                                                                        
                                                     






























                                                                        
                                                            








                                       
                                                 







                                                                  

                                                      

                                                    
               
                         
                





                                                                 
        

                                            

                                      

                                                          









                                                     

                                     


















































                                                          
                                  





























































































































































                                                                              






                                                    


                               
                                                            








                                        


                                        

































                                                                        


                                









































































                                                                        
%% 
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2004-2013. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%% 
%% -------------------------------------------------------------------------
%%
%% Some of the stuff stored here should really be persistent!!
%% (e.g. snmp-engine-boot)
%%
%% -------------------------------------------------------------------------

-module(snmpm_config).

-behaviour(gen_server).

%% External exports
%% Avoid warning for local function error/1 clashing with autoimported BIF.
-compile({no_auto_import,[error/1]}).
-export([start_link/1, stop/0, is_started/0]).
-export([register_user/4, unregister_user/1, 
	 which_users/0, 
	 user_info/0, user_info/1, user_info/2, 

	 register_agent/3, unregister_agent/2, 
	 agent_info/0, agent_info/2, agent_info/3, 
	 update_agent_info/3, update_agent_info/4, 
	 which_agents/0, which_agents/1, 

	 is_known_engine_id/2, 
	 get_agent_engine_id/1, 
	 get_agent_engine_max_message_size/1, 
	 get_agent_version/1, 
	 get_agent_mp_model/1, 
	 get_agent_user_id/1, get_agent_user_id/2, 
	 get_agent_user_info/2, 
	 
	 system_info/0, system_info/1, 
	 %% update_system_info/2, 
	 get_engine_id/0, get_engine_max_message_size/0,

	 register_usm_user/3, unregister_usm_user/2, 
	 which_usm_users/0, which_usm_users/1, 
	 usm_user_info/3, update_usm_user_info/4, 
	 get_usm_user/2, get_usm_user_from_sec_name/2, 
	 is_usm_engine_id_known/1,
	 get_engine_boots/0, get_engine_time/0, 
	 set_engine_boots/1, set_engine_time/1, 
	 get_usm_eboots/1, get_usm_etime/1, get_usm_eltime/1, 
	 set_usm_eboots/2, set_usm_etime/2, set_usm_eltime/2, 
	 reset_usm_cache/1, 
	 

	 cre_counter/2,
	 incr_counter/2,
	 increment_counter/3, increment_counter/4, 

	 cre_stats_counter/2,
	 maybe_cre_stats_counter/2,
	 incr_stats_counter/2,
	 reset_stats_counter/1,
	 get_stats_counters/0, get_stats_counter/1,

	 load_mib/1, unload_mib/1, which_mibs/0, 
	 make_mini_mib/0,
	 name_to_oid/1, oid_to_name/1, oid_to_type/1, 

	 system_start_time/0,

	 info/0, 
	 verbosity/1,

	 backup/1,

	 mk_target_name/3,
	 
	 default_transport_domain/0

	]).

%% Backward compatibillity exports
-export([
	 register_user/3,
	 unregister_agent/3, 
	 update_agent_info/5,
	 is_known_engine_id/3, 
	 get_agent_engine_id/2, 
	 get_agent_engine_max_message_size/2, 
	 get_agent_version/2, 
	 get_agent_mp_model/2
	]).

-export([check_manager_config/1, 
	 check_user_config/1, 
	 check_agent_config/1,
	 check_usm_user_config/1]).


%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, 
	 code_change/3, terminate/2]).


%% Includes:
-include_lib("kernel/include/file.hrl").
-include("snmp_types.hrl").
-include("snmpm_internal.hrl").
-include("snmpm_usm.hrl").
-include("snmp_debug.hrl").
-include("snmp_verbosity.hrl").


%% Types:
-record(user, {id, mod, data, default_agent_config}).

-record(state, {backup}).


%% Macros and Constants:
-define(SERVER,             ?MODULE).
-define(BACKUP_DB,          snmpm_config_backup).
-define(CONFIG_DB,          snmpm_config_db).

-define(DEFAULT_USER,       default_user).

-define(DEFAULT_AGENT_PORT, 161).

-define(IRB_DEFAULT,        auto).
%% -define(IRB_DEFAULT,        {user, timer:seconds(15)}).

-define(USER_MOD_DEFAULT,   snmpm_user_default).
-define(USER_DATA_DEFAULT,  undefined).

%% -define(DEF_ADDR_TAG, default_addr_tag).
-define(DEFAULT_TARGETNAME, default_agent).
-define(DEF_PORT_TAG,       default_port_tag).
-define(SUPPORTED_DOMAINS,  [transportDomainUdpIpv4, transportDomainUdpIpv6]).

-ifdef(snmp_debug).
-define(GS_START_LINK(Opts),
	gen_server:start_link({local, ?SERVER}, ?MODULE, [Opts], 
			      [{debug,[trace]}])).
-else.
-define(GS_START_LINK(Opts),
	gen_server:start_link({local, ?SERVER}, ?MODULE, [Opts], [])).
-endif.



%%%-------------------------------------------------------------------
%%% API
%%%-------------------------------------------------------------------

default_transport_domain() ->
    transportDomainUdpIpv4.


start_link(Opts) -> 
    ?d("start_link -> entry with"
       "~n   Opts: ~p", [Opts]),
    ?GS_START_LINK(Opts).

stop() ->
    call(stop).

is_started() ->
    call(is_started, 1000).

backup(BackupDir) when is_list(BackupDir) ->
    call({backup, BackupDir}).

%% Backward compatibillity
register_user(UserId, UserMod, UserData) ->
    register_user(UserId, UserMod, UserData, []).

register_user(UserId, UserMod, UserData, DefaultAgentConfig) 
  when (UserId =/= ?DEFAULT_USER) andalso is_list(DefaultAgentConfig) ->
    case (catch verify_user_behaviour(UserMod)) of
	ok ->
	    Config = default_agent_config(DefaultAgentConfig),
	    call({register_user, UserId, UserMod, UserData, Config});
	Error ->
	    Error
    end;
register_user(UserId, _UserMod, _UserData, DefaultAgentConfig) 
  when (UserId =/= ?DEFAULT_USER) ->
    {error, {bad_default_agent_config, DefaultAgentConfig}};
register_user(UserId, _, _, _) ->
    {error, {bad_user_id, UserId}}.

default_agent_config(DefaultAgentConfig) ->
    {ok, SystemDefaultAgentConfig} = agent_info(),
    default_agent_config(SystemDefaultAgentConfig, DefaultAgentConfig).

default_agent_config([], DefaultAgentConfig) ->
    DefaultAgentConfig;
default_agent_config([{Key, _} = Entry|T], DefaultAgentConfig) ->
    case lists:keysearch(Key, 1, DefaultAgentConfig) of
	{value, _} ->
	    default_agent_config(T, DefaultAgentConfig);
	false ->
	    default_agent_config(T, [Entry|DefaultAgentConfig])
    end.


verify_user_behaviour(UserMod) ->
    case snmp_misc:verify_behaviour(snmpm_user, UserMod) of
	ok ->
	    ok;
	Error ->
	    %% This user may implement the old behaviour, check it
	    case snmp_misc:verify_behaviour(snmpm_user_old, UserMod) of
		ok ->
		    ok;
		_ ->
		    throw(Error)
	    end
    end.


unregister_user(UserId) when UserId =/= ?DEFAULT_USER ->
    call({unregister_user, UserId});
unregister_user(BadUserId) ->
    {error, {bad_user_id, BadUserId}}.


which_users() ->
    Pattern = #user{id = '$1', _ = '_'},
    Match   = ets:match(snmpm_user_table, Pattern),
    [UserId || [UserId] <- Match, UserId =/= ?DEFAULT_USER].


user_info() ->
    UserId = ?DEFAULT_USER,
    case user_info(UserId) of
	{ok, Mod, Data} ->
	    {ok, UserId, Mod, Data};
	Error ->
	    Error
    end.

user_info(UserId) ->
    case ets:lookup(snmpm_user_table, UserId) of
	[#user{mod = UserMod, data = UserData}] ->
	    {ok, UserMod, UserData};
	_ ->
	    {error, not_found}
    end.

user_info(UserId, Item) ->
    case (catch do_user_info(UserId, Item)) of
	{'EXIT', _} ->
	    {error, {not_found, Item}};
	Val ->
	    {ok, Val}
    end.

do_user_info(UserId, module) ->
    ets:lookup_element(snmpm_user_table, UserId, #user.mod);
do_user_info(UserId, data) ->
    ets:lookup_element(snmpm_user_table, UserId, #user.data);
do_user_info(UserId, default_agent_config) ->
    ets:lookup_element(snmpm_user_table, UserId, #user.default_agent_config);
do_user_info(_UserId, BadItem) ->
    error({not_found, BadItem}).


%% A target-name constructed in this way is a string with the following: 
%% <IP-address>:<Port>-<Version>
%% This is intended for backward compatibility and therefor has
%% only support for IPv4 addresses and *no* other transport domain.
mk_target_name(Addr0, Port, Config) when is_list(Config) ->
    Version = 
	case lists:keysearch(version, 1, Config) of
	    {value, {_, V}} ->
		V;
	    false ->
		select_lowest_supported_version()
	end,
    case normalize_address(Addr0) of
	{A, B, C, D} ->
	    lists:flatten(
	      io_lib:format("~w.~w.~w.~w:~w-~w", [A, B, C, D, Port, Version]));
	[A, B, C, D] ->
	    lists:flatten(
	      io_lib:format("~w.~w.~w.~w:~w-~w", [A, B, C, D, Port, Version]));
	_ -> 
	    lists:flatten(
	      io_lib:format("~p:~w-~w", [Addr0, Port, Version]))
    end.
	
select_lowest_supported_version() ->
    {ok, Versions} = system_info(versions),
    select_lowest_supported_version([v1, v2, v3], Versions).

select_lowest_supported_version([], Versions) ->
    error({bad_versions, Versions});
select_lowest_supported_version([H|T], Versions) ->
    case lists:member(H, Versions) of
	true ->
	    H;
	false ->
	    select_lowest_supported_version(T, Versions)
    end.


register_agent(UserId, _TargetName, _Config0) when (UserId =:= user_id) ->
    {error, {bad_user_id, UserId}};
register_agent(UserId, TargetName, Config0) 
  when (is_list(TargetName) andalso 
	(length(TargetName) > 0) andalso 
	is_list(Config0)) ->

    ?vtrace("register_agent -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p"
	    "~n   Config0:    ~p", [UserId, TargetName, Config0]),

    %% Check: 
    %%   1) That the mandatory configs are present
    %%   2) That no illegal config, e.g. user_id (used internally), 
    %%      is not present
    %%   3) Check that there are no invalid or erroneous configs
    %%   4) Check that the manager is capable of using the selected version
    case verify_agent_config(Config0) of
	{ok, Config} ->
	    call({register_agent, UserId, TargetName, Config});
	Error ->
	    Error
    end.


verify_agent_config(Conf0) ->
    try
	begin
	    verify_mandatory(Conf0, [engine_id, address, reg_type]),
	    verify_invalid(Conf0, [user_id]),
	    Conf = verify_agent_config3(Conf0),
	    Vsns = versions(),
	    Vsn  = which_version(Conf),
	    verify_version(Vsn, Vsns),
	    {ok, Conf}
	end
    catch
	throw:Error ->
	    Error
    end.

versions() ->
    case system_info(versions) of
	{ok, Vsns} ->
	    Vsns;
	{error, _} = ERROR ->
	    throw(ERROR)
    end.

which_version(Conf) ->
    case lists:keysearch(version, 1, Conf) of
	{value, {version, V}} ->
	    V;
	false ->
	    v1
    end.

verify_version(Vsn, Vsns) ->
    case lists:member(Vsn, Vsns) of
	true ->
	    ok;
	false ->
	    Reason = {version_not_supported_by_manager, Vsn, Vsns}, 
	    throw({error, Reason})
    end.

verify_agent_config3(Conf0) ->
    %% Fix (transport) address and domain
    {TDomain, Conf1} = 
	case lists:keysearch(tdomain, 1, Conf0) of
	    {value, {tdomain, Dom}} ->
		{Dom, Conf0};
	    false ->
		Dom = default_transport_domain(), 
		{Dom, [{tdomain, Dom} | Conf0]}
	end,
    Conf2 = case lists:keysearch(address, 1, Conf1) of
		{value, {address, Address}} ->
		    lists:keyreplace(address, 1, Conf1, 
				     {address, {TDomain, Address}});
		false ->
		    %% This is a mandatory config option, 
		    %% a later test will detect this
		    Conf1
	    end,
    case verify_agent2(Conf2) of
	{ok, Conf} ->
	    Conf;
	{error, _} = ERROR ->
	    throw(ERROR)
    end.

verify_agent_config2(Conf) ->
    verify_agent2(Conf).


unregister_agent(UserId, TargetName) ->
    call({unregister_agent, UserId, TargetName}).

%% This is the old style agent unregistration (using Addr and Port).
unregister_agent(UserId, Addr0, Port) ->
    Addr = normalize_address(Addr0),
    case do_agent_info(Addr, Port, target_name) of
	{ok, TargetName} ->
	    unregister_agent(UserId, TargetName);
	Error ->
	    Error
    end.

agent_info() ->
    agent_info(?DEFAULT_TARGETNAME, all).

agent_info(TargetName, all) ->
    case ets:match_object(snmpm_agent_table, {{TargetName, '_'}, '_'}) of
	[] ->
	    {error, not_found};
	All ->
	    {ok, [{Item, Val} || {{_, Item}, Val} <- All]}
    end;
agent_info(TargetName, Item) ->
    case ets:lookup(snmpm_agent_table, {TargetName, Item}) of
	[{_, Val}] ->
	    {ok, Val};
	[] ->
	    {error, not_found}
    end.
    
agent_info(Addr0, Port, Item) ->
    Addr = normalize_address(Addr0),
    do_agent_info(Addr, Port, Item).

do_agent_info(Addr, Port, target_name = Item) ->
    case ets:lookup(snmpm_agent_table, {Addr, Port, Item}) of
	[{_, Val}] ->
	    {ok, Val};
	[] ->
	    {error, not_found}
    end;
do_agent_info(Addr, Port, Item) ->
    case do_agent_info(Addr, Port, target_name) of
	{ok, TargetName} ->
	    agent_info(TargetName, Item);
	Error ->
	    Error
    end.


which_agents() ->
    which_agents('_').

which_agents(UserId) ->
    Pat = {{'$1', user_id}, UserId},
    Agents = ets:match(snmpm_agent_table, Pat),
    [TargetName || [TargetName] <- Agents].


verify_agent_info(TargetName, Info0) ->
    try 
	begin
	    verify_invalid(Info0, [user_id]), 
	    %% Check if address is part of the list and
	    %% if so update it with the domain info. 
	    Info = 
		case lists:keysearch(address, 1, Info0) of
		    {value, {address, Addr}} ->
			%% If domain is part of the info, then use it.
			%% If not, lookup what is already stored for 
			%% this agent and use that.
			Domain = 
			    case lists:keysearch(tdomain, 1, Info0) of
				{value, {tdomain, Dom}} ->
				    Dom;
				false ->
				    {ok, Dom} = 
					agent_info(TargetName, tdomain),
				    Dom
			    end,
			Addr2 = {Domain, Addr}, 
			lists:keyreplace(address, 1, Info0, {address, Addr2});
		    false ->
			Info0
		end,
	    verify_agent2(Info)
	end
    catch
	throw:Error ->
	    Error
    end.

update_agent_info(UserId, TargetName, Info) ->
    call({update_agent_info, UserId, TargetName, Info}).

%% <BACKWARD-COMPAT-2>
%% This is wrapped in the interface module, so this function is
%% only here to catch code-upgrade problems.
update_agent_info(UserId, TargetName, Item, Val) ->
    update_agent_info(UserId, TargetName, [{Item, Val}]).
%% </BACKWARD-COMPAT-2>

%% <BACKWARD-COMPAT-1>
update_agent_info(UserId, Addr, Port, Item, Val)  ->
    case agent_info(Addr, Port, target_name) of
	{ok, TargetName} ->
	    update_agent_info(UserId, TargetName, Item, Val);
	Error ->
	    Error
    end.
%% </BACKWARD-COMPAT-1>

is_known_engine_id(EngineID, TargetName) ->
    case agent_info(TargetName, engine_id) of
	{ok, EngineID} ->
	    true;
	{ok, _OtherEngineID} ->
	    false;
	_ ->
	    false
    end.
    
%% Backward compatibillity
is_known_engine_id(EngineID, Addr, Port) ->
    case agent_info(Addr, Port, target_name) of
	{ok, TargetName} ->
	    is_known_engine_id(EngineID, TargetName);
	_ ->
	    false
    end.

get_agent_engine_id(TargetName) ->
    agent_info(TargetName, engine_id).

%% Backward compatibillity
get_agent_engine_id(Addr, Port) ->
    agent_info(Addr, Port, engine_id).

get_agent_engine_max_message_size(TargetName) ->
    agent_info(TargetName, max_message_size).

%% Backward compatibillity
get_agent_engine_max_message_size(Addr, Port) ->
    agent_info(Addr, Port, max_message_size).

get_agent_version(TargetName) ->
    agent_info(TargetName, version). 

%% Backward compatibillity
get_agent_version(Addr, Port) ->
    agent_info(Addr, Port, version). 

get_agent_mp_model(TargetName) ->
    case agent_info(TargetName, version) of
	{ok, v2} ->
	    {ok, v2c};
	{ok, V} ->
	    {ok, V};
	Err ->
	    Err
    end.

%% Backward compatibillity
get_agent_mp_model(Addr, Port) ->
    case agent_info(Addr, Port, target_name) of
	{ok, TargetName} ->
	    get_agent_mp_model(TargetName);
	Error ->
	    Error
    end.

get_agent_user_id(TargetName) ->
    agent_info(TargetName, user_id).

get_agent_user_id(Addr, Port) ->
    agent_info(Addr, Port, user_id).

get_agent_user_info(Addr, Port) ->
    case agent_info(Addr, Port, target_name) of
	{ok, Target} ->
	    case agent_info(Target, reg_type) of
		{ok, RegType} ->
		    case agent_info(Target, user_id) of
			{ok, UserId} ->
			    {ok, UserId, Target, RegType};
			{error, not_found} ->
			    {error, {user_id_not_found, Target}}
		    end;
		{error, not_found} ->
		    {error, {reg_type_not_found, Target}}
	    end;
	{error, not_found} ->
	    {error, {target_name_not_found, Addr, Port}}
    end.
	    


system_info() ->
    system_info(all).

system_info(all) ->
    lists:sort(ets:tab2list(snmpm_config_table));
system_info(Key) when is_atom(Key) ->
    case ets:lookup(snmpm_config_table, Key) of
	[{_, Val}] ->
	    {ok, Val};
	_ ->
	    {error, not_found}
    end.

%% update_system_info(Key, Val) ->
%%     call({update_system_info, Key, Val}).

system_start_time() ->
    system_info(system_start_time).

get_engine_id() ->
    system_info(engine_id).

get_engine_max_message_size() ->
    system_info(max_message_size).

get_engine_boots() ->
    case dets:lookup(?CONFIG_DB, snmp_engine_boots) of
	[{_, Boots}] ->
	    {ok, Boots};
	_ ->
	    {error, not_found}
    end.

set_engine_boots(Boots) ->
    case (whereis(?SERVER) =:= self()) of
	false ->
	    call({set_engine_boots, Boots});
	true ->
	    dets:insert(?CONFIG_DB, {snmp_engine_boots, Boots}),
	    ok
    end.
    

get_engine_time() ->
    case system_info(snmp_engine_base) of
	{ok, EngineBase} ->
	    {ok, snmp_misc:now(sec) - EngineBase};
	Error ->
	    Error
    end.

get_usm_eboots(SnmpEngineID) ->
    Key = {eboots, SnmpEngineID},
    case get_usm_cache(Key) of
	{ok, Boots} ->
	    {ok, Boots};
	_ ->
	    {ok, 0}
    end.

get_usm_etime(SnmpEngineID) ->
    Key = {etime, SnmpEngineID},
    case get_usm_cache(Key) of
	{ok, Diff} ->
	    {ok, snmp_misc:now(sec) - Diff};
	_ ->
	    {ok, 0}
    end.

get_usm_eltime(SnmpEngineID) ->
    Key = {eltime, SnmpEngineID},
    case get_usm_cache(Key) of
	{ok, Time} ->
	    {ok, Time};
	_ ->
	    {ok, 0}
    end.

get_usm_cache(Key) ->
    case ets:lookup(snmpm_usm_table, {usm_cache, Key}) of
	[{_, Val}] ->
	    {ok, Val};
	_ ->
	    {error, not_found}
    end.
    
set_usm_eboots(SnmpEngineID, EngineBoots) ->
    set_usm_cache({eboots, SnmpEngineID}, EngineBoots).

set_usm_etime(SnmpEngineID, Diff) ->
    set_usm_cache({etime, SnmpEngineID}, Diff).

set_usm_eltime(SnmpEngineID, Time) ->
    set_usm_cache({eltime, SnmpEngineID}, Time).

set_usm_cache(Key, Val) ->
    call({set_usm_cache, Key, Val}).

reset_usm_cache(SnmpEngineID) ->
    case (whereis(?SERVER) =:= self()) of
	false ->
	    call({reset_usm_cache, SnmpEngineID});
	true ->
	    Pat = {{usm_cache, {'_', SnmpEngineID}}, '_'},
	    ets:match_delete(snmpm_usm_table, Pat),
	    ok
    end.

set_engine_time(Time) ->
    call({set_engine_time, Time}).

register_usm_user(EngineID, Name, Config) 
  when is_list(EngineID) andalso is_list(Name) ->
    case verify_usm_user_config(EngineID, Name, Config) of
	{ok, User} ->
	    call({register_usm_user, User});
	Error ->
	    Error
    end.

unregister_usm_user(EngineID, Name) 
  when is_list(EngineID) andalso is_list(Name) ->
    call({unregister_usm_user, EngineID, Name}).

verify_usm_user_config(EngineID, Name, Config) ->
    try
	begin
	    verify_mandatory(Config, []), 
	    verify_invalid(Config, [engine_id, name]),
	    verify_usm_user_config2(EngineID, Name, Config)
	end
    catch 
	throw:Error ->
	    Error
    end.

verify_usm_user_config2(EngineID, Name, Config) ->
    SecName = verify_usm_user_get(sec_name, Name,              Config),
    Auth    = verify_usm_user_get(auth,     usmNoAuthProtocol, Config),
    AuthKey = verify_usm_user_get(auth_key, [],                Config),
    Priv    = verify_usm_user_get(priv,     usmNoPrivProtocol, Config),
    PrivKey = verify_usm_user_get(priv_key, [],                Config),
    User = {EngineID, Name, SecName, Auth, AuthKey, Priv, PrivKey},
    verify_usm_user(User).
	
verify_usm_user_get(Item, Default, Config) ->	
    case lists:keysearch(Item, 1, Config) of
	{value, {_, Val}} ->
	    Val;
	false ->
	    Default
    end.

which_usm_users() ->
    Pattern = {usm_key('$1', '$2'), '_'},
    Match   = ets:match(snmpm_usm_table, Pattern),
    [{EngineID, UserName} || [EngineID, UserName] <- Match].

which_usm_users(EngineID) ->
    Pattern = {usm_key(EngineID, '$1'), '_'},
    Match   = ets:match(snmpm_usm_table, Pattern),
    [UserName || [UserName] <- Match].

usm_user_info(EngineID, UserName, Item) ->
    case ets:lookup(snmpm_usm_table, usm_key(EngineID, UserName)) of
	[] ->
	    {error, not_found};
	[{_Key, UsmUser}] ->
	    do_usm_user_info(UsmUser, Item)
    end.

do_usm_user_info(#usm_user{sec_name = SecName}, sec_name) ->
    {ok, SecName};
do_usm_user_info(#usm_user{auth = AuthP}, auth) ->
    {ok, AuthP};
do_usm_user_info(#usm_user{auth_key = AuthKey}, auth_key) ->
    {ok, AuthKey};
do_usm_user_info(#usm_user{priv = PrivP}, priv) ->
    {ok, PrivP};
do_usm_user_info(#usm_user{priv_key = PrivKey}, priv_key) ->
    {ok, PrivKey};
do_usm_user_info(#usm_user{engine_id = EngineID}, engine_id) ->
    {ok, EngineID};
do_usm_user_info(#usm_user{name = Name}, name) ->
    {ok, Name};
do_usm_user_info(_, Item) ->
    {error, {bad_iten, Item}}.

update_usm_user_info(EngineID, UserName, Item, Val) 
  when (Item =/= engine_id) andalso (Item =/= name) ->
    call({update_usm_user_info, EngineID, UserName, Item, Val}).

get_usm_user(EngineID, UserName) ->
    Key = usm_key(EngineID, UserName),
    case ets:lookup(snmpm_usm_table, Key) of
	[{_, User}] ->
	    {ok, User};
	_ ->
	    {error, not_found}
    end.

is_usm_engine_id_known(EngineID) ->
    Pattern = {usm_key(EngineID, '$1'), '_'},
    case ets:match(snmpm_usm_table, Pattern) of
	[] ->
	    false;
	_ ->
	    true
    end.

get_usm_user_from_sec_name(EngineID, SecName) ->
    %% Since the normal mapping between UserName and SecName is the
    %% identity-function, we first try to use the SecName as UserName,
    %% and check the resulting row.  If it doesn't match, we'll have to
    %% loop through the entire table.
    Key = usm_key(EngineID, SecName),
    case ets:lookup(snmpm_usm_table, Key) of
	[{Key, #usm_user{sec_name = SecName} = User}] ->
	    {ok, User};
	_ ->
	    %% That did not work, so we have to search
	    Pattern = {usm_key(EngineID, '_'), 
		       #usm_user{sec_name = SecName, _ = '_'}},
	    case ets:match_object(snmpm_usm_table, Pattern) of
		[{_, User}|_] ->
		    {ok, User};
		_ ->
		    {error, not_found}
	    end
    end.


%% Wrap-counters (wrapping at 2147483647 or 4294967295)
cre_counter(Counter, Initial) ->
    case (whereis(?SERVER) =:= self()) of
	false ->
	    call({cre_counter, Counter, Initial});
	true ->
	    ets:insert(snmpm_counter_table, {Counter, Initial}),
	    Initial
    end.

incr_counter(usm_salt, Incr) ->        % Backward compatibillity (upgrade)
    incr_counter(usm_des_salt, Incr);  % Backward compatibillity (upgrade)
incr_counter(usm_des_salt, Incr) ->
    incr_counter(usm_des_salt, Incr, 4294967295);
incr_counter(usm_aes_salt, Incr) ->
    incr_counter(usm_aes_salt, Incr, 36893488147419103231);
incr_counter(Counter, Incr) ->
    incr_counter(Counter, Incr, 2147483647).

incr_counter(Counter, Incr, Wrap) ->
    case (catch ets:update_counter(snmpm_counter_table, Counter, Incr)) of
	{'EXIT', _} ->
	    cre_counter(Counter, Incr);
	NewVal when NewVal =< Wrap ->
	    NewVal;
	N ->
	    cre_counter(Counter, N - Wrap)
    end.


%% <ATL Sequence Number>
increment_counter(Counter, Initial, Max) ->
    Increment = 1, 
    increment_counter(Counter, Initial, Increment, Max).

increment_counter(Counter, Initial, Increment, Max) ->
    %% This is to make sure no one else increments our counter
    Key = {Counter, self()},

    %% Counter data
    Position  = 2,
    Threshold = Max,
    SetValue  = Initial,
    UpdateOp  = {Position, Increment, Threshold, SetValue},

    %% And now for the actual increment
    Tab = snmpm_counter_table, 
    case (catch ets:update_counter(Tab, Key, UpdateOp)) of
        {'EXIT', {badarg, _}} ->
            %% Oups, first time
            ets:insert(Tab, {Key, Initial}),
            Initial;
        Next when is_integer(Next) ->
            Next
    end.
%% </ATL Sequence Number>


maybe_cre_stats_counter(Counter, Initial) ->
    case ets:lookup(snmpm_stats_table, Counter) of
	[_] ->
	    ok;
	_ ->
	    cre_stats_counter(Counter, Initial)
    end.
			      
cre_stats_counter(Counter, Initial) ->
    case (whereis(?SERVER) =:= self()) of
	false ->
	    call({cre_stats_counter, Counter, Initial});
	true ->
	    ets:insert(snmpm_stats_table, {Counter, Initial}),
	    Initial
    end.

incr_stats_counter(Counter, Incr) ->
    case (catch ets:update_counter(snmpm_stats_table, Counter, Incr)) of
	{'EXIT', _} ->
	    cre_counter(Counter, Incr);
	NewVal ->
	    NewVal
    end.

reset_stats_counter(Counter) ->
    case (whereis(?SERVER) =:= self()) of
	false ->
	    call({reset_stats_counter, Counter});
	true ->
	    ets:insert(snmpm_stats_table, {Counter, 0})
    end,
    ok.
    
get_stats_counter(Counter) ->
    case ets:lookup(snmpm_stats_table, Counter) of
	[{Counter, Value}] ->
	    {ok, Value};
	_ ->
	    {error, not_found}
    end.
    
get_stats_counters() ->
    ets:tab2list(snmpm_stats_table).
    
load_mib(Mib) when is_list(Mib) ->
    call({load_mib, Mib}).

unload_mib(Mib) when is_list(Mib) ->
    call({unload_mib, Mib}).

which_mibs() ->
    Pattern = {{mib, '_'}, '$1', '$2'},
    Mibs = ets:match(snmpm_mib_table, Pattern),
    [list_to_tuple(X) || X <- Mibs].

name_to_oid(Name) ->
    Pat = {{mini_mib, '$1'}, Name, '_', '_'},
    case ets:match(snmpm_mib_table, Pat) of
	[] ->
	    {error, not_found};
	X ->
	    Oids = [Oid || [Oid] <- X],
	    {ok, Oids}
    end.

oid_to_name(Oid) ->
    case ets:lookup(snmpm_mib_table, {mini_mib, Oid}) of
	[{_, Name, _, _}] ->
	    {ok, Name};
	[] ->
	    {error, not_found}
    end.

oid_to_type(Oid) ->
    case ets:lookup(snmpm_mib_table, {mini_mib, Oid}) of
	[{_, _, Type, _}] ->
	    {ok, Type};
	[] ->
	    {error, not_found}
    end.

make_mini_mib() ->
    Pat = {{mini_mib, '$1'}, '$2', '$3', '_'},
    MiniElems = ets:match(snmpm_mib_table, Pat),
    lists:keysort(1, [list_to_tuple(MiniElem) || MiniElem <- MiniElems]).


info() ->
    call(info).

verbosity(Verbosity) ->
    case ?vvalidate(Verbosity) of
	Verbosity ->
	    call({verbosity, Verbosity});
	_ ->
	    {error, {invalid_verbosity, Verbosity}}
    end.


%%%-------------------------------------------------------------------
%%% Callback functions from gen_server
%%%-------------------------------------------------------------------

%%--------------------------------------------------------------------
%% Func: init/1
%% Returns: {ok, State}          |
%%          {ok, State, Timeout} |
%%          ignore               |
%%          {stop, Reason}
%%--------------------------------------------------------------------
init([Opts]) ->
%     put(sname, mconf),
%     put(verbosity, trace),
    ?d("init -> entry with"
       "~n   Opts: ~p", [Opts]),
    case (catch do_init(Opts)) of
	ok ->
	    {ok, #state{}};
	{error, Reason} ->
	    error_msg("init error: ~p", [Reason]),
	    {stop, Reason};
	{'EXIT', Reason} ->
	    error_msg("init exit: ~p", [Reason]),
	    {stop, Reason};
	Error ->
	    error_msg("init failed: ~p", [Error]),
	    {stop, Error}
    end.

do_init(Opts) ->
    process_flag(trap_exit, true),
    %% Mandatory = [versions, {config, [dir]}],
    Mandatory = [{config, [dir, db_dir]}],
    verify_options(Opts, Mandatory),

    ets:new(snmpm_counter_table, [set, public,    named_table, {keypos, 1}]),
    ets:new(snmpm_stats_table,   [set, public,    named_table, {keypos, 1}]),
    ets:new(snmpm_mib_table,     [set, protected, named_table, {keypos, 1}]),
    ets:new(snmpm_config_table,  [set, protected, named_table, {keypos, 1}]),
    ets:new(snmpm_agent_table,   [set, protected, named_table, {keypos, 1}]),
    ets:new(snmpm_user_table,    [set, protected, named_table, {keypos, 2}]),
    ets:new(snmpm_usm_table,     [set, protected, named_table, {keypos, 1}]),

    %% -- System start time --
    ets:insert(snmpm_config_table, {system_start_time, snmp_misc:now(cs)}),
    
    %% --- Own options (dir and db_dir mandatory) ---
    ConfOpts      = get_opt(config,        Opts,     []),
    ConfVerb      = get_opt(verbosity,     ConfOpts, silence),
    ConfDir       = get_opt(dir,           ConfOpts),
    ConfDbDir     = get_opt(db_dir,        ConfOpts),
    ConfDbInitErr = get_opt(db_init_error, ConfOpts, terminate),
    ConfRep       = get_opt(repair,        ConfOpts, true),
    ConfAs        = get_opt(auto_save,     ConfOpts, 5000),
    ets:insert(snmpm_config_table, {config_verbosity,     ConfVerb}),
    ets:insert(snmpm_config_table, {config_dir,           ConfDir}),
    ets:insert(snmpm_config_table, {config_db_dir,        ConfDbDir}),
    ets:insert(snmpm_config_table, {config_db_init_error, ConfDbInitErr}),
    ets:insert(snmpm_config_table, {config_repair,        ConfRep}),
    ets:insert(snmpm_config_table, {config_auto_save,     ConfAs}),
    put(sname, mconf),
    put(verbosity, ConfVerb),
    ?vlog("starting", []),

    %% -- Create dets file used for storing persistent data --
    dets_open(ConfDbDir, ConfDbInitErr, ConfRep, ConfAs),
    
    %% -- Prio (optional) --
    Prio = get_opt(priority, Opts, normal),
    ets:insert(snmpm_config_table, {prio, Prio}),
    process_flag(priority, Prio),

    %% -- Server (optional) --
    ServerOpts = get_opt(server,         Opts,      []),
    ServerVerb = get_opt(verbosity,      ServerOpts, silence),
    ServerGct  = get_opt(timeout,        ServerOpts, 30000),
    ServerMt   = get_opt(multi_threaded, ServerOpts, true),
    ets:insert(snmpm_config_table, {server_verbosity,      ServerVerb}),
    ets:insert(snmpm_config_table, {server_timeout,        ServerGct}),
    ets:insert(snmpm_config_table, {server_multi_threaded, ServerMt}),
   
    %% -- Mibs (optional) --
    ?vdebug("initiate mini mib", []),
    Mibs = get_opt(mibs, Opts, []),
    ets:insert(snmpm_config_table, {mibs, Mibs}),
    init_mini_mib(Mibs),

    %% -- Net-if (optional) --
    ?vdebug("net_if options", []),
    NetIfIrb     = 
	case get_opt(inform_request_behaviour, Opts, ?IRB_DEFAULT) of
	    user ->
		{user, timer:seconds(15)};
	    Irb ->
		Irb
	end,
    NetIfOpts    = get_opt(net_if,                    Opts,      []),
    NetIfMod     = get_opt(module,                    NetIfOpts, snmpm_net_if),
    NetIfVerb    = get_opt(verbosity,                 NetIfOpts, silence),
    NetIfOptions = get_opt(options,                   NetIfOpts, []),
    ets:insert(snmpm_config_table, {net_if_module,    NetIfMod}),
    ets:insert(snmpm_config_table, {net_if_verbosity, NetIfVerb}),
    ets:insert(snmpm_config_table, {net_if_irb,       NetIfIrb}),
    ets:insert(snmpm_config_table, {net_if_options,   NetIfOptions}),

    %% -- Versions (optional) --
    %% -- Versions (mandatory) ???????????? --
    ?vdebug("versions", []),
    Vsns = get_opt(versions, Opts, [v1, v2, v3]),
    ets:insert(snmpm_config_table, {versions, Vsns}),

    %% -- Audit trail log (optional) --
    ?vdebug("audit trail log", []),
    case get_opt(audit_trail_log, Opts, []) of
	[] ->
	    ?vtrace("no ATL", []),
	    ets:insert(snmpm_config_table, {audit_trail_log, false});
	AuditTrailLogOpts ->
	    ?vtrace("ATL options: ~p", [AuditTrailLogOpts]),
	    ets:insert(snmpm_config_table, {audit_trail_log, true}),
	    LogDir   = get_atl_dir(AuditTrailLogOpts),
	    LogType  = get_atl_type(AuditTrailLogOpts),
	    LogSize  = get_atl_size(AuditTrailLogOpts),
	    LogRep   = get_atl_repair(AuditTrailLogOpts),
	    LogSeqNo = get_atl_seqno(AuditTrailLogOpts),
	    ets:insert(snmpm_config_table, {audit_trail_log_dir,    LogDir}),
	    ets:insert(snmpm_config_table, {audit_trail_log_type,   LogType}),
	    ets:insert(snmpm_config_table, {audit_trail_log_size,   LogSize}),
	    ets:insert(snmpm_config_table, {audit_trail_log_repair, LogRep}),
	    ets:insert(snmpm_config_table, {audit_trail_log_seqno,  LogSeqNo})
    end,

    %% -- System default agent config --
    ?vdebug("system default agent config", []),
    init_agent_default(),

    %% -- User (optional) --
    ?vdebug("default user", []),
    DefUserMod  = get_opt(def_user_mod,  Opts, ?USER_MOD_DEFAULT),
    DefUserData = get_opt(def_user_data, Opts, ?USER_DATA_DEFAULT),
    ets:insert(snmpm_config_table, {def_user_mod,  DefUserMod}),
    ets:insert(snmpm_config_table, {def_user_data, DefUserData}),
    
    {ok, SystemDefaultAgentConfig}       = agent_info(),
    DefUser = #user{id                   = ?DEFAULT_USER, 
		    mod                  = DefUserMod, 
		    data                 = DefUserData,
		    default_agent_config = SystemDefaultAgentConfig},
    ok = handle_register_user(DefUser),
    
    %% -- Note store --
    ?vdebug("note store", []),
    NoteStoreOpts    = get_opt(note_store, Opts, []),
    NoteStoreVerb    = get_opt(verbosity,  NoteStoreOpts, silence),
    NoteStoreTimeout = get_opt(timeout,    NoteStoreOpts, 30000),
    ets:insert(snmpm_config_table, {note_store_verbosity, NoteStoreVerb}),
    ets:insert(snmpm_config_table, {note_store_timeout,   NoteStoreTimeout}),
    
    %% -- Manager SNMP config --
    ?vdebug("manager snmp config", []),
    MgrConf = read_manager_config_file(ConfDir),
    init_manager_config(MgrConf),

    %% -- User config --
    ?vdebug("users config", []),
    Users = read_users_config_file(ConfDir),
    init_users_config(Users),

    %% -- Agents config --
    ?vdebug("agents config", []),
    Agents = read_agents_config_file(ConfDir),
    init_agents_config(Agents),

    %% -- USM config --
    UsmUsers = read_usm_config_file(ConfDir),
    init_usm_users_config(UsmUsers),

    %% -- snmp engine init --
    init_engine(),

    ?vlog("started", []),
    ok.


dets_open(Dir, DbInitError, Repair, AutoSave) ->
    Name     = ?CONFIG_DB, 
    Filename = dets_filename(Name, Dir),
    case file:read_file_info(Filename) of
	{ok, _} ->
	    %% File exists
	    case do_dets_open(Name, Filename, Repair, AutoSave) of
		{ok, _Dets} ->
		    ok;
		{error, Reason1} ->
                    info_msg("Corrupt local database: ~p", [Filename]),
		    case DbInitError of
			terminate ->
			    error({failed_reopen_dets, Filename, Reason1});
			_ ->
			    Saved = Filename ++ ".saved",
			    file:rename(Filename, Saved),
			    case do_dets_open(Name, Filename, 
					      Repair, AutoSave) of
				{ok, _Dets} ->
				    ok;
				{error, Reason2} ->
				    error({failed_open_dets, Filename, 
					   Reason1, Reason2})
			    end
		    end
	    end;
	_ ->
	    case DbInitError of
		create_db_and_dir ->
		    ok = filelib:ensure_dir(Filename);
		_ ->
		    ok
	    end,
	    case do_dets_open(Name, Filename, Repair, AutoSave) of
		{ok, _Dets} ->
		    ok;
		{error, Reason} ->
		    error({failed_open_dets, Filename, Reason})
	    end
    end.
		
do_dets_open(Name, Filename, Repair, AutoSave) ->
    Opts = [{repair,    Repair}, 
	    {auto_save, AutoSave}, 
	    {file,      Filename}],
    dets:open_file(Name, Opts).


dets_filename(Name, Dir) when is_atom(Name) ->
    dets_filename(atom_to_list(Name), Dir);
dets_filename(Name, Dir) ->
    filename:join(dets_filename1(Dir), Name).

dets_filename1([])  -> ".";
dets_filename1(Dir) -> Dir.


%% ------------------------------------------------------------------------

init_engine() ->
    case get_engine_boots() of
	{ok, Val} when Val < 2147483647 ->
	    set_engine_boots(Val + 1);
	{ok, _} ->
	    ok;
	_ ->
	    set_engine_boots(1)
    end,
    reset_engine_base().

reset_engine_base() ->
    ets:insert(snmpm_config_table, {snmp_engine_base, snmp_misc:now(sec)}).


%% ------------------------------------------------------------------------

verify_options(Opts, Mandatory) ->
    ?d("verify_options -> entry with"
       "~n   Opts:      ~p"
       "~n   Mandatory: ~p", [Opts, Mandatory]),
    verify_mandatory_options(Opts, Mandatory),
    verify_options(Opts).

%% mandatory() -> [mand()]
%% mand() -> atom() | {atom, [atom()]}
verify_mandatory_options(_Opts, []) ->
    ok;
verify_mandatory_options(Opts, [Mand|Mands]) ->
    verify_mandatory_option(Opts, Mand),
    verify_mandatory_options(Opts, Mands).

verify_mandatory_option(Opts, {Mand, MandSubOpts}) ->
    ?d("verify_mandatory_option -> entry with"
       "~n   Mand:        ~p"
       "~n   MandSubObjs: ~p", [Mand, MandSubOpts]),
    case lists:keysearch(Mand, 1, Opts) of
	{value, {Mand, SubOpts}} ->
	    verify_mandatory_options(SubOpts, MandSubOpts);
	false ->
	    ?d("missing mandatory option: ~w [~p]", [Mand, MandSubOpts]),
	    error({missing_mandatory, Mand, MandSubOpts})
    end;
verify_mandatory_option(Opts, Mand) ->
    ?d("verify_mandatory_option -> entry with"
       "~n   Mand:        ~p", [Mand]),
    case lists:keymember(Mand, 1, Opts) of
	true ->
	    ok;
	false ->
	    ?d("missing mandatory option: ~w", [Mand]),
	    error({missing_mandatory, Mand})
    end.
	
verify_options([]) ->
    ?d("verify_options -> done", []),
    ok;
verify_options([Opt|Opts]) ->
    ?d("verify_options -> entry with"
       "~n   Opt: ~p", [Opt]),
    verify_option(Opt),
    verify_options(Opts).

verify_option({prio, Prio}) ->
    verify_prio(Prio);
verify_option({mibs, Mibs}) ->
    verify_mibs(Mibs);
verify_option({inform_request_behaviour, IRB}) ->
    verify_irb(IRB);
verify_option({net_if, NetIfOpts}) ->
    verify_net_if_opts(NetIfOpts);
verify_option({server, ServerOpts}) ->
    verify_server_opts(ServerOpts);
verify_option({note_store, NoteStoreOpts}) ->
    verify_note_store_opts(NoteStoreOpts);
verify_option({config, ConfOpts0}) ->
    %% Make sure any db_dir option is first in the options list to make it
    %% easier to check if the db_init_error option specifies that a missing
    %% db_dir should be created.
    ConfOpts = case lists:keytake(db_dir, 1, ConfOpts0) of
                   false -> ConfOpts0;
                   {value, Result, OtherOpts} -> [Result|OtherOpts]
               end,
    verify_config_opts(ConfOpts);
verify_option({versions, Vsns}) ->
    verify_versions(Vsns);
verify_option({audit_trail_log, LogOpts}) ->
    Mandatory = [dir, size],
    case (catch verify_mandatory_options(LogOpts, Mandatory)) of
	ok ->
	    verify_audit_trail_log_opts(LogOpts);
	{error, {missing_mandatory, LogOpt}} ->
	    error({missing_mandatory, audit_trail_log, LogOpt})
    end;
verify_option({def_user_mod, Mod}) ->
    verify_module(def_user_mod, Mod);
verify_option({def_user_data, _Data}) ->
    ok;
verify_option(Opt) ->
    {error, {invalid_option, Opt}}.

verify_prio(Prio) when is_atom(Prio) ->
    ok;
verify_prio(Prio) ->
    error({invalid_prio, Prio}).

verify_irb(auto) ->
    ok;
verify_irb(user) ->
    ok;
verify_irb({user, To}) when is_integer(To) andalso (To > 0) ->
    ok;
verify_irb(IRB) ->
    error({invalid_irb, IRB}).

verify_mibs([]) ->
    ok;
verify_mibs([Mib|Mibs]) when is_list(Mib) ->
    verify_mibs(Mibs);
verify_mibs(Mibs) ->
    error({invalid_mibs, Mibs}).

verify_config_opts([]) ->
    ok;
verify_config_opts([{verbosity, Verbosity}|Opts]) ->
    verify_verbosity(Verbosity),
    verify_config_opts(Opts);
verify_config_opts([{dir, Dir}|Opts]) ->
    verify_conf_dir(Dir),
    verify_config_opts(Opts);
verify_config_opts([{db_dir, Dir}|Opts]) ->
    case lists:keyfind(db_init_error, 1, Opts) of
        {db_init_error, create_db_and_dir} ->
            verify_conf_db_dir(Dir, false);
        _ ->
            verify_conf_db_dir(Dir, true)
    end,
    verify_config_opts(Opts);
verify_config_opts([{db_init_error, DbInitErr}|Opts]) ->
    verify_conf_db_init_error(DbInitErr),
    verify_config_opts(Opts);
verify_config_opts([{repair, Repair}|Opts]) ->
    verify_conf_repair(Repair),
    verify_config_opts(Opts);
verify_config_opts([{auto_save, AutoSave}|Opts]) ->
    verify_conf_auto_save(AutoSave),
    verify_config_opts(Opts);
verify_config_opts([Opt|_]) ->
    error({invalid_config_option, Opt}).

verify_server_opts([]) ->
    ok;
verify_server_opts([{verbosity, Verbosity}|Opts]) ->
    verify_verbosity(Verbosity),
    verify_server_opts(Opts);
verify_server_opts([{timeout, Timeout}|Opts]) ->
    verify_server_timeout(Timeout),
    verify_server_opts(Opts);
verify_server_opts([Opt|_]) ->
    error({invalid_server_option, Opt}).

verify_server_timeout(T) when is_integer(T) andalso (T > 0) ->
    ok;
verify_server_timeout(T) ->
    error({invalid_server_timeout, T}).

verify_net_if_opts([]) ->
    ok;
verify_net_if_opts([{module, Mod}|Opts]) ->
    verify_network_interface_behaviour(Mod),
    verify_net_if_opts(Opts);
verify_net_if_opts([{verbosity, Verbosity}|Opts]) ->
    verify_verbosity(Verbosity),
    verify_net_if_opts(Opts);
verify_net_if_opts([{options, Options}|Opts]) when is_list(Options) ->
    verify_net_if_opts(Opts);
verify_net_if_opts([Opt|_]) ->
    error({invalid_net_if_option, Opt}).

verify_network_interface_behaviour(Mod) ->
    case snmp_misc:verify_behaviour(snmpm_network_interface, Mod) of
	ok ->
	    ok;
	Error ->
	    throw(Error)
    end.
    
    
verify_note_store_opts([]) ->
    ok;
verify_note_store_opts([{verbosity, Verbosity}|Opts]) ->
    verify_verbosity(Verbosity),
    verify_note_store_opts(Opts);
verify_note_store_opts([{timeout, Timeout}|Opts]) ->
    verify_note_store_timeout(Timeout),
    verify_note_store_opts(Opts);
verify_note_store_opts([Opt|_]) ->
    error({invalid_note_store_option, Opt}).

verify_note_store_timeout(T) when is_integer(T) andalso (T > 0) ->
    ok;
verify_note_store_timeout(T) ->
    error({invalid_note_store_timeout, T}).

verify_conf_dir(Dir) ->
    case (catch verify_dir(Dir)) of
	ok ->
	    ok;
	{error, Reason} ->
	    error({invalid_conf_dir, Dir, Reason});
	_ ->
	    error({invalid_conf_dir, Dir})
    end.

verify_conf_db_dir(Dir, true) ->
    case (catch verify_dir(Dir)) of
	ok ->
	    ok;
	{error, Reason} ->
	    error({invalid_conf_db_dir, Dir, Reason});
	_ ->
	    error({invalid_conf_db_dir, Dir})
    end;
verify_conf_db_dir(_Dir, false) ->
    ok.

verify_conf_db_init_error(terminate) ->
    ok;
verify_conf_db_init_error(create) ->
    ok;
verify_conf_db_init_error(create_db_and_dir) ->
    ok;
verify_conf_db_init_error(InvalidDbInitError) ->
    error({invalid_conf_db_init_error, InvalidDbInitError}).


verify_conf_repair(true) ->
    ok;
verify_conf_repair(false) ->
    ok;
verify_conf_repair(force) ->
    ok;
verify_conf_repair(InvalidRepair) ->
    error({invalid_conf_db_repair, InvalidRepair}).


verify_conf_auto_save(infinity) ->
    ok;
verify_conf_auto_save(AutoSave) 
  when is_integer(AutoSave) andalso (AutoSave > 0) ->
    ok;
verify_conf_auto_save(InvalidAutoSave) ->
    error({invalid_conf_db_auto_save, InvalidAutoSave}).


verify_versions([]) ->
    ok;
verify_versions([Vsn|Vsns]) ->
    verify_version(Vsn),
    verify_versions(Vsns).

verify_version(v1) ->
    ok;
verify_version(v2) ->
    ok;
verify_version(v3) ->
    ok;
verify_version(Vsn) ->
    error({invalid_version, Vsn}).

verify_audit_trail_log_opts([]) ->
    ok;
verify_audit_trail_log_opts([{dir, Dir}|Opts]) ->
    verify_log_dir(Dir),
    verify_audit_trail_log_opts(Opts);
verify_audit_trail_log_opts([{type, Type}|Opts]) ->
    verify_log_type(Type),
    verify_audit_trail_log_opts(Opts);
verify_audit_trail_log_opts([{size, Size}|Opts]) ->
    verify_log_size(Size),
    verify_audit_trail_log_opts(Opts);
verify_audit_trail_log_opts([{repair, Repair}|Opts]) ->
    verify_log_repair(Repair),
    verify_audit_trail_log_opts(Opts);
verify_audit_trail_log_opts([{seqno, SeqNo}|Opts]) ->
    verify_log_seqno(SeqNo),
    verify_audit_trail_log_opts(Opts);
verify_audit_trail_log_opts([Opt|_Opts]) ->
    error({invalid_audit_trail_log_option, Opt}).

verify_log_type(read) ->
    ok;
verify_log_type(write) ->
    ok;
verify_log_type(read_write) ->
    ok;
verify_log_type(Type) ->
    error({invalid_audit_trail_log_type, Type}).

verify_log_dir(Dir) ->
    case (catch verify_dir(Dir)) of
	ok ->
	    ok;
	{error, Reason} ->
	    error({invalid_audit_trail_log_dir, Dir, Reason});
	_ ->
	    error({invalid_audit_trail_log_dir, Dir})
    end.

verify_log_size(Sz) when is_integer(Sz) andalso (Sz > 0) ->
    ok;
verify_log_size(infinity) ->
    ok;
verify_log_size({MaxNoBytes, MaxNoFiles}) 
  when (is_integer(MaxNoBytes) andalso 
	(MaxNoBytes > 0) andalso 
	is_integer(MaxNoFiles) andalso 
	(MaxNoFiles > 0) andalso 
	(MaxNoFiles < 65000)) ->
    ok;
verify_log_size(Sz) ->
    error({invalid_audit_trail_log_size, Sz}).

verify_log_repair(true) -> ok;
verify_log_repair(false) -> ok;
verify_log_repair(truncate) -> ok;
verify_log_repair(Repair) ->
    error({invalid_audit_trail_log_repair, Repair}).

verify_log_seqno(true) -> ok;
verify_log_seqno(false) -> ok;
verify_log_seqno(SeqNo) ->
    error({invalid_audit_trail_log_seqno, SeqNo}).


verify_module(_, Mod) when is_atom(Mod) ->
    ok;
verify_module(ReasonTag, Mod) ->
    error({invalid_module, ReasonTag, Mod}).

% verify_bool(_, true) ->
%     ok;
% verify_bool(_, false) ->
%     ok;
% verify_bool(ReasonTag, Bool) ->
%     error({invalid_bool, ReasonTag, Bool}).

verify_dir(Dir) when is_list(Dir) ->
    case file:read_file_info(Dir) of
	{ok, #file_info{type = directory}} ->
	    ok;
	{ok, _} ->
	    {error, not_directory};
	{error, _Reason} ->
	    {error, not_found}
    end;
verify_dir(Dir) ->
    {error, {invalid_log_dir, Dir}}.


verify_verbosity(Verbosity) ->
    case snmp_verbosity:validate(Verbosity) of
	Verbosity ->
	    ok;
	_ ->
	    error({invalid_verbosity, Verbosity})
    end.
    
%% ------------------------------------------------------------------------

init_manager_config([]) ->
    ok;
init_manager_config([{Key, Val}|Confs]) ->
    ets:insert(snmpm_config_table, {Key, Val}),
    init_manager_config(Confs).



init_agent_default() ->
    %% The purpose of the default_agent is only to have a place
    %% to store system wide default values related to agents.
    %% 

    %% Port
    init_agent_default(port, ?DEFAULT_AGENT_PORT),

    %% Timeout
    init_agent_default(timeout, 10000),

    %% Max message (packet) size
    init_agent_default(max_message_size, 484),

    %% MPModel
    init_agent_default(version, v2),

    %% SecModel
    init_agent_default(sec_model, v2c),

    %% SecName
    init_agent_default(sec_name, "initial"),

    %% SecLevel
    init_agent_default(sec_level, noAuthNoPriv),

    %% Community
    init_agent_default(community, "all-rights"),
    ok.


init_agent_default(Item, Val) when Item =/= user_id ->
    case do_update_agent_info(default_agent, Item, Val) of
	ok ->
	    ok;
	{error, Reason} ->
	    error(Reason)
    end.


read_agents_config_file(Dir) ->
    Check = fun(C) -> check_agent_config2(C) end,
    case read_file(Dir, "agents.conf", Check, []) of
	{ok, Conf} ->
	    Conf;
	Error ->
	    ?vlog("agent config error: ~p", [Error]),
	    throw(Error)
    end.

check_agent_config2(Agent) ->
    case (catch check_agent_config(Agent)) of
	{ok, {UserId, TargetName, Conf, Version}} ->
	    {ok, Vsns} = system_info(versions),
	    case lists:member(Version, Vsns) of
		true ->
		    {ok, {UserId, TargetName, Conf}};
		false ->
		    error({version_not_supported_by_manager, 
			   Version, Vsns})
	    end;
	Err ->
	    throw(Err)
    end.

%% For backward compatibility
check_agent_config({UserId, 
		    TargetName, 
		    Community, 
		    Ip, Port, 
		    EngineId, 
		    Timeout, MaxMessageSize, 
		    Version, SecModel, SecName, SecLevel}) ->
    TDomain = default_transport_domain(),
    check_agent_config({UserId, 
			TargetName, 
			Community, 
			TDomain, Ip, Port, 
			EngineId, 
			Timeout, MaxMessageSize, 
			Version, SecModel, SecName, SecLevel});

check_agent_config({UserId, 
		    TargetName, 
		    Community, 
		    TDomain, Ip, Port, 
		    EngineId, 
		    Timeout, MaxMessageSize, 
		    Version, SecModel, SecName, SecLevel}) ->
    ?vtrace("check_agent_config -> entry with"
	    "~n   UserId:         ~p"
	    "~n   TargetName:     ~p"
	    "~n   Community:      ~p"
	    "~n   TDomain:        ~p"
	    "~n   Ip:             ~p"
	    "~n   Port:           ~p"
	    "~n   EngineId:       ~p"
	    "~n   Timeout:        ~p"
	    "~n   MaxMessageSize: ~p"
	    "~n   Version:        ~p"
	    "~n   SecModel:       ~p"
	    "~n   SecName:        ~p"
	    "~n   SecLevel:       ~p", 
	    [UserId, TargetName, Community, 
	     TDomain, Ip, Port, 
	     EngineId, Timeout, MaxMessageSize, 
	     Version, SecModel, SecName, SecLevel]),
    Addr = normalize_address(TDomain, Ip),
    ?vtrace("check_agent_config -> Addr: ~p", [Addr]),
    Agent = {UserId, 
	     TargetName, 
	     Community, 
	     TDomain, Addr, Port, 
	     EngineId, 
	     Timeout, MaxMessageSize, 
	     Version, SecModel, SecName, SecLevel},
    {ok, verify_agent(Agent)};
check_agent_config(Agent) ->
    error({bad_agent_config, Agent}).


init_agents_config([]) ->
    ok;
init_agents_config([Agent|Agents]) ->
    init_agent_config(Agent),
    init_agents_config(Agents).

init_agent_config({_UserId, ?DEFAULT_TARGETNAME = TargetName, _Config}) ->
    throw({error, {invalid_target_name, TargetName}});
init_agent_config({UserId, TargetName, Config}) ->
    case handle_register_agent(UserId, TargetName, Config) of
	ok ->
	    ok;
	Error ->
	    throw(Error)
    end.


%% For backward compatibility
verify_agent({UserId, 
	      TargetName, 
	      Comm, 
	      Ip, Port, 
	      EngineId, 
	      Timeout, MMS, 
	      Version, SecModel, SecName, SecLevel}) ->
    TDomain = default_transport_domain(),
    verify_agent({UserId, 
		  TargetName, 
		  Comm, 
		  TDomain, Ip, Port, 
		  EngineId, 
		  Timeout, MMS, 
		  Version, SecModel, SecName, SecLevel});

verify_agent({UserId, 
	      TargetName, 
	      Comm, 
	      TDomain, Ip, Port, 
	      EngineId, 
	      Timeout, MMS, 
	      Version, SecModel, SecName, SecLevel}) ->
    ?vdebug("verify_agent -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p", [UserId, TargetName]),
    snmp_conf:check_string(TargetName, {gt, 0}),
    snmp_conf:check_integer(Port, {gt, 0}),
    %% Note that the order of Conf *is* important.
    %% Some properties may depend on others, so that
    %% in order to verify one property, another must
    %% be already verified (and present). An example 
    %% of this is the property 'address', for which
    %% the property tdomain is needed.
    Conf0 = 
	[{reg_type,         target_name},
	 {tdomain,          TDomain}, 
	 %% This should be taddress, but what the*...
	 {address,          {TDomain, Ip}},
	 {port,             Port},
	 {community,        Comm}, 
	 {engine_id,        EngineId},
	 {timeout,          Timeout},
	 {max_message_size, MMS},
	 {version,          Version},
	 {sec_model,        SecModel},
	 {sec_name,         SecName},
	 {sec_level,        SecLevel}
	],
    case verify_agent2(Conf0) of
	{ok, Conf} ->
	    {UserId, TargetName, Conf, Version};
	Err ->
	    throw(Err)
    end.

verify_agent2(Conf) -> 
    verify_agent2(Conf, []).

verify_agent2([], VerifiedConf) ->
    {ok, VerifiedConf};
verify_agent2([{Item, Val0}|Items], VerifiedConf) ->
    case verify_val(Item, Val0) of
	{ok, Val} ->
	    verify_agent2(Items, [{Item, Val} | VerifiedConf]);
	Err ->
	    Err
    end;
verify_agent2([Bad|_], _VerifiedConf) ->
    {error, {bad_agent_config, Bad}}.


read_users_config_file(Dir) ->
    Check = fun(C) -> check_user_config(C) end,
    case read_file(Dir, "users.conf", Check, []) of
	{ok, Conf} ->
	    Conf;
	Error ->
	    ?vlog("failure reading users config file: ~n   ~p", [Error]),
	    throw(Error)
    end.


check_user_config({Id, Mod, Data}) ->
    ?vtrace("check_user_config -> entry with"
	    "~n   Id:   ~p"
	    "~n   Mod:  ~p"
	    "~n   Data: ~p", [Id, Mod, Data]),
    check_user_config({Id, Mod, Data, []});
check_user_config({Id, Mod, Data, DefaultAgentConfig} = _User) 
  when (Id =/= ?DEFAULT_USER) andalso is_list(DefaultAgentConfig) ->
    ?vtrace("check_user_config -> entry with"
	    "~n   Id:                 ~p"
	    "~n   Mod:                ~p"
	    "~n   Data:               ~p"
	    "~n   DefaultAgentConfig: ~p", 
	    [Id, Mod, Data, DefaultAgentConfig]),
    case (catch verify_user_behaviour(Mod)) of
	ok ->
	    ?vtrace("check_user_config -> user behaviour verified", []),
	    case verify_user_agent_config(DefaultAgentConfig) of
		{ok, DefAgentConf} ->
		    ?vtrace("check_user_config -> "
			    "user agent (default) config verified", []),
		    User2 = {Id, Mod, Data, DefAgentConf}, 
	    	    {ok, User2};
		{error, Reason} ->
		    error({bad_default_agent_config, Reason})
	    end;
	Error ->
	    throw(Error)
    end;
check_user_config({Id, _Mod, _Data, DefaultAgentConfig}) 
  when (Id =/= ?DEFAULT_USER) ->
    {error, {bad_default_agent_config, DefaultAgentConfig}};
check_user_config({Id, _Mod, _Data, _DefaultAgentConfig}) ->
    error({bad_user_id, Id});
check_user_config(User) ->
    error({bad_user_config, User}).

init_users_config([]) ->
    ok;
init_users_config([User|Users]) ->
    init_user_config(User),
    init_users_config(Users).

init_user_config(User) ->
    case (catch verify_user(User)) of
	{ok, UserRec} ->
	    case handle_register_user(UserRec) of
		ok ->
		    ok;
		{error, Reason} ->
		    error_msg("failed register user: "
			      "~n~w~n~w", [User, Reason])
	    end;
	{error, Reason} ->
	    error_msg("user config check failed: "
		      "~n~w~n~w", [User, Reason])
    end.
   
verify_user({Id, UserMod, UserData}) ->
    verify_user({Id, UserMod, UserData, []});
verify_user({Id, UserMod, UserData, DefaultAgentConfig}) 
  when (Id =/= ?DEFAULT_USER) andalso is_list(DefaultAgentConfig) ->
    ?d("verify_user -> entry with"
       "~n   Id:                 ~p"
       "~n   UserMod:            ~p"
       "~n   UserData:           ~p"
       "~n   DefaultAgentConfig: ~p", 
       [Id, UserMod, UserData, DefaultAgentConfig]),
    case (catch verify_user_behaviour(UserMod)) of
	ok ->
	    case verify_user_agent_config(DefaultAgentConfig) of
		{ok, DefAgentConf} ->
		    Config = default_agent_config(DefAgentConf),
		    {ok, #user{id                   = Id, 
			       mod                  = UserMod, 
			       data                 = UserData, 
			       default_agent_config = Config}};
		{error, Reason} ->
		    error({bad_default_agent_config, Reason})
	    end;
	Error ->
	    throw(Error)
    end;
verify_user({Id, _UserMod, _UserData, DefaultAgentConfig}) 
  when (Id =/= ?DEFAULT_USER) ->
    {error, {bad_default_agent_config, DefaultAgentConfig}};
verify_user({Id, _, _, _}) ->
    {error, {bad_user_id, Id}}.

verify_user_agent_config(Conf) ->
    try
	begin
	    verify_invalid(Conf, [user_id, engine_id, address]),
	    verify_agent_config2(Conf)
	end
    catch
	throw:Error ->
	    ?vdebug("verify_user_agent_config -> throw"
		    "~n   Error: ~p", [Error]),
	    Error
    end.

read_usm_config_file(Dir) ->
    Check = fun(C) -> check_usm_user_config(C) end,
    case read_file(Dir, "usm.conf", Check, []) of
	{ok, Conf} ->
	    Conf;
	Error ->
	    throw(Error)
    end.

%% Identity-function
check_usm_user_config({EngineId, Name, 
		       AuthP, AuthKey, 
		       PrivP, PrivKey}) ->
    User = {EngineId, Name, Name, AuthP, AuthKey, PrivP, PrivKey},
    verify_usm_user(User);
check_usm_user_config({_EngineId, _Name, _SecName, 
		       _AuthP, _AuthKey, 
		       _PrivP, _PrivKey} = User) ->
    verify_usm_user(User);
check_usm_user_config(User) ->
    error({bad_usm_config, User}).

init_usm_users_config([]) ->
    ok;
init_usm_users_config([User|Users]) ->
    init_usm_user_config(User),
    init_usm_users_config(Users).

init_usm_user_config(User) when is_record(User, usm_user) ->
    case handle_register_usm_user(User) of
	ok ->
	    ok;
	Error ->
	    throw(Error)
    end;
init_usm_user_config(BadUser) ->
    error({bad_usm_user, BadUser}).


verify_usm_user({EngineID, Name, SecName, AuthP, AuthKey, PrivP, PrivKey}) ->
    ?d("verify_usm_user -> entry with"
       "~n   EngineID: ~p"
       "~n   Name:     ~p"
       "~n   SecName:  ~p"
       "~n   AuthP:    ~p"
       "~n   AuthKey:  ~p"
       "~n   PrivP:    ~p"
       "~n   PrivKey:  ~p", 
       [EngineID, Name, SecName, AuthP, AuthKey, PrivP, PrivKey]),
    verify_usm_user_engine_id(EngineID),
    verify_usm_user_name(Name),
    verify_usm_user_sec_name(SecName),
    verify_usm_user(AuthP, AuthKey, PrivP, PrivKey),
    User = #usm_user{engine_id = EngineID,
		     name      = Name,
		     sec_name  = SecName,
		     auth      = AuthP, 
		     auth_key  = AuthKey,
		     priv      = PrivP, 
		     priv_key  = PrivKey},
    {ok, User}.

verify_usm_user_engine_id(EngineID) ->
    case (catch snmp_conf:check_string(EngineID, {gt, 0})) of
	ok ->
	    ok;
	_ ->
	    error({bad_usm_engine_id, EngineID})
    end.

verify_usm_user_name(Name) ->
    case (catch snmp_conf:check_string(Name, {gt, 0})) of
	ok ->
	    ok;
	_ ->
	    error({bad_usm_user_name, Name})
    end.

verify_usm_user_sec_name(Name) ->
    case (catch snmp_conf:check_string(Name, {gt, 0})) of
	ok ->
	    ok;
	_ ->
	    error({bad_usm_sec_name, Name})
    end.

verify_usm_user(AuthP, AuthKey, PrivP, PrivKey) ->
    verify_usm_user_auth(AuthP, AuthKey),
    verify_usm_user_priv(PrivP, PrivKey),
    ok.

verify_usm_user_auth(usmNoAuthProtocol, AuthKey) ->
    case (catch snmp_conf:check_string(AuthKey, any)) of
	ok ->
	    ok;
	_ ->
	    error({invalid_auth_key, usmNoAuthProtocol})
    end;
verify_usm_user_auth(usmHMACMD5AuthProtocol, AuthKey) 
  when is_list(AuthKey) andalso (length(AuthKey) =:= 16) ->
    case is_crypto_supported(md5) of
	true -> 
	    case snmp_conf:all_integer(AuthKey) of
		true ->
		    ok;
		_ ->
		    error({invalid_auth_key, usmHMACMD5AuthProtocol})
	    end;
	false -> 
	    error({unsupported_crypto, md5})
    end;    
verify_usm_user_auth(usmHMACMD5AuthProtocol, AuthKey) when is_list(AuthKey) ->
    Len = length(AuthKey),
    error({invalid_auth_key, usmHMACMD5AuthProtocol, Len});
verify_usm_user_auth(usmHMACMD5AuthProtocol, _AuthKey) ->
    error({invalid_auth_key, usmHMACMD5AuthProtocol});
verify_usm_user_auth(usmHMACSHAAuthProtocol, AuthKey) 
  when is_list(AuthKey) andalso (length(AuthKey) =:= 20) ->
    case is_crypto_supported(sha) of
	true -> 
	    case snmp_conf:all_integer(AuthKey) of
		true ->
		    ok;
		_ ->
		    error({invalid_auth_key, usmHMACSHAAuthProtocol})
	    end;
	false -> 
	    error({unsupported_crypto, sha})
    end;
verify_usm_user_auth(usmHMACSHAAuthProtocol, AuthKey) when is_list(AuthKey) ->
    Len = length(AuthKey),
    error({invalid_auth_key, usmHMACSHAAuthProtocol, Len});
verify_usm_user_auth(usmHMACSHAAuthProtocol, _AuthKey) ->
    error({invalid_auth_key, usmHMACSHAAuthProtocol});
verify_usm_user_auth(AuthP, _AuthKey) ->
    error({invalid_auth_protocol, AuthP}).
    
verify_usm_user_priv(usmNoPrivProtocol, PrivKey) ->
    case (catch snmp_conf:check_string(PrivKey, any)) of
	ok ->
	    ok;
	_ ->
	    error({invalid_priv_key, usmNoPrivProtocol})
    end;
verify_usm_user_priv(usmDESPrivProtocol, PrivKey) 
  when (length(PrivKey) =:= 16) ->
    case is_crypto_supported(des_cbc) of
	true -> 
	    case snmp_conf:all_integer(PrivKey) of
		true ->
		    ok;
		_ ->
		    error({invalid_priv_key, usmDESPrivProtocol})
	    end;
	false -> 
	    error({unsupported_crypto, des_cbc})
    end;
verify_usm_user_priv(usmDESPrivProtocol, PrivKey) when is_list(PrivKey) ->
    Len = length(PrivKey),
    error({invalid_priv_key, usmDESPrivProtocol, Len});
verify_usm_user_priv(usmDESPrivProtocol, _PrivKey) ->
    error({invalid_priv_key, usmDESPrivProtocol});
verify_usm_user_priv(usmAesCfb128Protocol, PrivKey) 
  when (length(PrivKey) =:= 16) ->
    case is_crypto_supported(aes_cfb128) of
	true -> 
	    case snmp_conf:all_integer(PrivKey) of
		true ->
		    ok;
		_ ->
		    error({invalid_priv_key, usmAesCfb128Protocol})
	    end;
	false -> 
	    error({unsupported_crypto, aes_cfb128})
    end;
verify_usm_user_priv(usmAesCfb128Protocol, PrivKey) when is_list(PrivKey) ->
    Len = length(PrivKey),
    error({invalid_priv_key, usmAesCfb128Protocol, Len});
verify_usm_user_priv(usmAesCfb128Protocol, _PrivKey) ->
    error({invalid_priv_key, usmAesCfb128Protocol});
verify_usm_user_priv(PrivP, _PrivKey) ->
    error({invalid_priv_protocol, PrivP}).
    

-compile({inline, [{is_crypto_supported,1}]}).
is_crypto_supported(Func) ->
    snmp_misc:is_crypto_supported(Func). 
 

read_manager_config_file(Dir) ->
    Check = fun(Conf) -> check_manager_config(Conf) end,
    case read_file(Dir, "manager.conf", Check) of
	{ok, Conf} ->
	    ?d("read_manager_config_file -> ok: "
	       "~n   Conf: ~p", [Conf]),
	    %% If the address is not specified, then we assume
	    %% it should be the local host.
	    %% If the address is not possible to determine
	    %% that way, then we give up...
	    check_mandatory_manager_config(Conf),
	    ensure_manager_config(Conf);
	Error ->
	    throw(Error)
    end.

default_manager_config() ->
    {ok, HostName} = inet:gethostname(),
    case inet:getaddr(HostName, inet) of
	{ok, A} ->
	    [{address, tuple_to_list(A)}];
	{error, _Reason} ->
	    ?d("default_manager_config -> failed getting address: "
	       "~n   _Reason: ~p", [_Reason]),
	    []
    end.
    
check_manager_config({address, Addr}) ->
    snmp_conf:check_ip(Addr);
check_manager_config({port, Port}) ->
    snmp_conf:check_integer(Port, {gt, 0});
check_manager_config({engine_id, EngineID}) ->
    snmp_conf:check_string(EngineID);
check_manager_config({max_message_size, Max}) ->
    snmp_conf:check_integer(Max, {gte, 484});
check_manager_config(Conf) ->
    {error, {unknown_config, Conf}}.


check_mandatory_manager_config(Conf) ->
    Mand  = [port, engine_id, max_message_size],
    check_mandatory_manager_config(Mand, Conf).

check_mandatory_manager_config([], _Conf) ->
    ok;
check_mandatory_manager_config([Item|Mand], Conf) ->
    case lists:keysearch(Item, 1, Conf) of
	false ->
	    error({missing_mandatory_manager_config, Item});
	_ ->
	    check_mandatory_manager_config(Mand, Conf)
    end.
    

ensure_manager_config(Confs) ->
    ensure_manager_config(Confs, default_manager_config()).

ensure_manager_config(Confs, []) ->
    Confs;
ensure_manager_config(Confs, [{Key,_} = DefKeyVal|Defs]) ->
    case lists:keysearch(Key, 1, Confs) of
	false ->
	    ensure_manager_config([DefKeyVal|Confs], Defs);
	{value, _Conf} ->
	    ensure_manager_config(Confs, Defs)
    end.

% ensure_manager_config([], Defs, Confs) ->
%     Confs ++ Defs;
% ensure_manager_config(Confs0, [{Key, DefVal}|Defs], Acc) ->
%     case lists:keysearch(Key, 1, Confs0) of
% 	false ->
% 	    ensure_manager_config(Confs0, Defs, [{Key, DefVal}|Acc]);
% 	{value, Conf} ->
% 	    Confs = lists:keydelete(Key, 1, Confs0),
% 	    ensure_manager_config(Confs, Defs, [Conf|Acc])
%     end.
			      


read_file(Dir, FileName, Check, Default) ->
    File = filename:join(Dir, FileName),
    case file:read_file_info(File) of
        {ok, _} ->
            case (catch do_read(File, Check)) of
		{ok, Conf} ->
		    {ok, Conf};
		Error ->
		    ?vtrace("read_file -> read failed:"
			    "~n   Error: ~p", [Error]),
		    Error
	    end;
        {error, Reason} ->
	    ?vlog("failed reading config from ~s: ~p", [FileName, Reason]),
	    {ok, Default}
    end.

read_file(Dir, FileName, Check) ->
    File = filename:join(Dir, FileName),
    case file:read_file_info(File) of
        {ok, _} ->
            case (catch do_read(File, Check)) of
		{ok, Conf} ->
		    ?vtrace("read_file -> read ok"
			    "~n   Conf: ~p", [Conf]),
		    {ok, Conf};
		Error ->
		    ?vtrace("read_file -> read failed:"
			    "~n   Error: ~p", [Error]),
		    Error
	    end;
        {error, Reason} ->
	    error_msg("failed reading config from ~s: ~p", [FileName, Reason]),
	    {error, {failed_reading, FileName, Reason}}
    end.

do_read(File, Check) ->
    {ok, snmp_conf:read(File, Check)}.


%%--------------------------------------------------------------------
%% Func: handle_call/3
%% Returns: {reply, Reply, State}          |
%%          {reply, Reply, State, Timeout} |
%%          {noreply, State}               |
%%          {noreply, State, Timeout}      |
%%          {stop, Reason, Reply, State}   | (terminate/2 is called)
%%          {stop, Reason, State}            (terminate/2 is called)
%%--------------------------------------------------------------------
handle_call({register_user, UserId, UserMod, UserData, DefaultAgentConfig}, 
	    _From, State) ->
    ?vlog("received register_user request: "
	  "~n   UserId:             ~p"
	  "~n   UserMod:            ~p"
	  "~n   UserData:           ~p"
	  "~n   DefaultAgentConfig: ~p", 
	  [UserId, UserMod, UserData, DefaultAgentConfig]),
    User  = #user{id                   = UserId, 
		  mod                  = UserMod, 
		  data                 = UserData,
		  default_agent_config = DefaultAgentConfig},
    Reply = handle_register_user(User),
    {reply, Reply, State};

handle_call({unregister_user, UserId}, _From, State) ->
    ?vlog("received unregister_user request: "
	  "~n   UserId: ~p", [UserId]),
    Reply = handle_unregister_user(UserId),
    {reply, Reply, State};

handle_call({register_agent, UserId, TargetName, Config}, _From, State) ->
    ?vlog("received register_agent request: "
	  "~n   UserId:     ~p"
	  "~n   TargetName: ~p"
	  "~n   Config:     ~p", [UserId, TargetName, Config]),
    Reply = handle_register_agent(UserId, TargetName, Config),
    {reply, Reply, State};

handle_call({unregister_agent, UserId, TargetName}, _From, State) ->
    ?vlog("received unregister_agent request: "
	  "~n   UserId:     ~p"
	  "~n   TargetName: ~p", [UserId, TargetName]),
    Reply = handle_unregister_agent(UserId, TargetName),
    {reply, Reply, State};

handle_call({update_agent_info, UserId, TargetName, Info}, 
	    _From, State) ->
    ?vlog("received update_agent_info request: "
	  "~n   UserId:     ~p"
	  "~n   TargetName: ~p"
	  "~n   Info:       ~p", [UserId, TargetName, Info]),
    Reply = handle_update_agent_info(UserId, TargetName, Info),
    {reply, Reply, State};

%% <BACKWARD-COMPAT>
handle_call({update_agent_info, UserId, TargetName, Item, Val}, 
	    _From, State) ->
    ?vlog("received update_agent_info request: "
	  "~n   UserId:     ~p"
	  "~n   TargetName: ~p"
	  "~n   Item:       ~p"
	  "~n   Val:        ~p", [UserId, TargetName, Item, Val]),
    Reply = handle_update_agent_info(UserId, TargetName, Item, Val),
    {reply, Reply, State};
%% </BACKWARD-COMPAT>

handle_call({register_usm_user, User}, _From, State) ->
    ?vlog("received register_usm_user request: "
	  "~n   User: ~p", [User]),
    Reply = handle_register_usm_user(User),
    {reply, Reply, State};

handle_call({unregister_usm_user, EngineID, Name}, _From, State) ->
    ?vlog("received register_usm_user request: "
	  "~n   EngineID: ~p"
	  "~n   Name:     ~p", [EngineID, Name]),
    Reply = handle_unregister_usm_user(EngineID, Name),
    {reply, Reply, State};

handle_call({update_usm_user_info, EngineID, UserName, Item, Val}, 
	    _From, State) ->
    ?vlog("received update_usm_user_info request: "
	  "~n   EngineID: ~p"
	  "~n   UserName: ~p"
	  "~n   Item:     ~p"
	  "~n   Val:      ~p", [EngineID, UserName, Item, Val]),
    Reply = handle_update_usm_user_info(EngineID, UserName, Item, Val),
    {reply, Reply, State};

handle_call({cre_counter, Counter, Initial}, _From, State) ->
    ?vlog("received cre_counter ~p -> ~w", [Counter, Initial]),
    Reply = cre_counter(Counter, Initial),
    {reply, Reply, State};

handle_call({cre_stats_counter, Counter, Initial}, _From, State) ->
    ?vlog("received cre_stats_counter ~p -> ~w", [Counter, Initial]),
    Reply = cre_stats_counter(Counter, Initial),
    {reply, Reply, State};

handle_call({reset_stats_counter, Counter}, _From, State) ->
    ?vlog("received reset_stats_counter ~p", [Counter]),
    Reply = reset_stats_counter(Counter),
    {reply, Reply, State};

handle_call({load_mib, Mib}, _From, State) ->
    ?vlog("received load_mib ~p", [Mib]),
    case handle_load_mib(Mib) of
	ok ->
	    {reply, ok, State};
	Error ->
	    {reply, Error, State}
    end;


handle_call({unload_mib, Mib}, _From, State) ->
    ?vlog("received unload_mib ~p", [Mib]),
    case handle_unload_mib(Mib) of
	ok ->
	    {reply, ok, State};
	Error ->
	    {reply, Error, State}
    end;


handle_call({set_engine_boots, Boots}, _From, State) ->
    ?vlog("received set_engine_boots ~p", [Boots]),
    set_engine_boots(Boots),
    {reply, ok, State};

handle_call({set_engine_time, Time}, _From, State) ->
    ?vlog("received set_engine_time ~p", [Time]),
    Base = snmp_misc:now(sec) - Time,
    ets:insert(snmpm_config_table, {snmp_engine_base, Base}),
    {reply, ok, State};

handle_call({set_usm_cache, Key, Val}, _From, State) ->
    ?vlog("received set_usm_cache: ~w -> ~p", [Key, Val]),
    ets:insert(snmpm_usm_table, {{usm_cache, Key}, Val}),
    {reply, ok, State};

handle_call({reset_usm_cache, EngineID}, _From, State) ->
    ?vlog("received reset_usm_cache: ~p", [EngineID]),
    reset_usm_cache(EngineID),
    {reply, ok, State};

handle_call({verbosity, Verbosity}, _From, State) ->
    ?vlog("received verbosity request", []),
    put(verbosity, Verbosity),
    {reply, ok, State};

handle_call(info, _From, State) ->
    ?vlog("received info request", []),
    Reply = get_info(),
    {reply, Reply, State};

handle_call({backup, BackupDir}, From, State) ->
    ?vlog("backup to ~p", [BackupDir]),
    Pid = self(),
    V   = get(verbosity),
    case file:read_file_info(BackupDir) of
        {ok, #file_info{type = directory}} ->
            BackupServer =
                erlang:spawn_link(
                  fun() ->
                          put(sname, mcbs),
                          put(verbosity, V),
                          Dir   = filename:join([BackupDir]),
                          Reply = handle_backup(?CONFIG_DB, Dir),
                          Pid ! {backup_done, Reply},
                          unlink(Pid)
                  end),
            ?vtrace("backup server: ~p", [BackupServer]),
            {noreply, State#state{backup = {BackupServer, From}}};
        {ok, _} ->
            {reply, {error, not_a_directory}, State};
        Error ->
            {reply, Error, State}
    end;


%% handle_call({update_system_info, Key, Val}, _From, State) ->
%%     ?vlog("received update_system_info: ~p -> ~p", [Key, Val]),
%%     Reply = handle_update_system_info(Key, Val),
%%     {reply, Reply, State};


handle_call(is_started, _From, State) ->
    ?vlog("received is_started request", []),
    {reply, true, State};


handle_call(stop, _From, State) ->
    {stop, normal, ok, State};


handle_call(Req, _From, State) ->
    warning_msg("received unknown request: ~n~p", [Req]),
    {reply, {error, unknown_request}, State}.


%%--------------------------------------------------------------------
%% Func: handle_cast/2
%% Returns: {noreply, State}          |
%%          {noreply, State, Timeout} |
%%          {stop, Reason, State}            (terminate/2 is called)
%%--------------------------------------------------------------------
handle_cast(Msg, State) ->
    warning_msg("received unknown message: ~n~p", [Msg]),
    {noreply, State}.


%%--------------------------------------------------------------------
%% Func: handle_info/2
%% Returns: {noreply, State}          |
%%          {noreply, State, Timeout} |
%%          {stop, Reason, State}            (terminate/2 is called)
%%--------------------------------------------------------------------
handle_info({'EXIT', Pid, Reason}, #state{backup = {Pid, From}} = S) ->
    ?vlog("backup server (~p) exited for reason ~n~p", [Pid, Reason]),
    gen_server:reply(From, {error, Reason}),
    {noreply, S#state{backup = undefined}};

handle_info({'EXIT', Pid, Reason}, S) ->
    %% The only other processes we should be linked to are
    %% either the server or our supervisor, so die...
    {stop, {received_exit, Pid, Reason}, S};

handle_info({backup_done, Reply}, #state{backup = {_, From}} = S) ->
    ?vlog("backup done:"
          "~n   Reply: ~p", [Reply]),
    gen_server:reply(From, Reply),
    {noreply, S#state{backup = undefined}};

handle_info(Info, State) ->
    warning_msg("received unknown info: ~n~p", [Info]),
    {noreply, State}.


%%--------------------------------------------------------------------
%% Func: terminate/2
%% Purpose: Shutdown the server
%% Returns: any (ignored by gen_server)
%%--------------------------------------------------------------------
terminate(Reason, _State) ->
    ?vdebug("terminate: ~p",[Reason]),
    ok.

%%----------------------------------------------------------------------
%% Func: code_change/3
%% Purpose: Convert process state when code is changed
%% Returns: {ok, NewState}
%%----------------------------------------------------------------------

%% downgrade
%%
code_change({down, _Vsn}, S1, downgrade_to_pre_4_7) ->
    #state{backup = B} = S1,
    stop_backup_server(B),
    S2 = {state},
    {ok, S2};

%% upgrade
%%
code_change(_Vsn, _S1, upgrade_from_pre_4_7) ->
    %% {state} = S1,
    S2 = #state{},
    {ok, S2};

code_change(_Vsn, State, _Extra) ->
    {ok, State}.


stop_backup_server(undefined) ->
    ok;
stop_backup_server({Pid, _}) when is_pid(Pid) ->
    exit(Pid, kill).



%%----------------------------------------------------------
%% Update system info
%%----------------------------------------------------------

%% handle_update_system_info(audit_trail_log_type = Key, Val) ->
%%     case snmpm_config:system_info(audit_trail_log) of
%% 	{ok, true} ->
%% 	    Value = 
%% 		case Val of
%% 		    read ->
%% 			{ok, [read]};
%% 		    write ->
%% 			{ok, [write]};
%% 		    read_write ->
%% 			{ok, [read,write]};
%% 		    _ ->
%% 			{error, {bad_value, Key, Val}}
%% 		end,
%% 	    case Value of
%% 		{ok, NewValue} ->
%% 		    ets:insert(snmpm_config_table, {Key, NewValue}),
%% 		    ok;
%% 		false ->
%% 		    Value
%% 	    end;
%% 	_ ->
%% 	    {error, audit_trail_log_not_enabled}
%%     end;
%% handle_update_system_info(BadKey, Val) ->
%%     {error, {unsupported_update, BadKey, Val}}.


%%----------------------------------------------------------
%% Backup
%%----------------------------------------------------------

handle_backup(D, BackupDir) ->
    %% First check that we do not wrote to the corrent db-dir...
    ?vtrace("handle_backup -> entry with"
        "~n   D:         ~p"
        "~n   BackupDir: ~p", [D, BackupDir]),
    case dets:info(D, filename) of
        undefined ->
            ?vinfo("handle_backup -> no file to backup", []),
            {error, no_file};
        Filename ->
            ?vinfo("handle_backup -> file to backup: ~n   ~p", [Filename]),
            case filename:dirname(Filename) of
                BackupDir ->
                    ?vinfo("handle_backup -> backup dir and db dir the same",
                           []),
                    {error, db_dir};
                _ ->
                    case file:read_file_info(BackupDir) of
                        {ok, #file_info{type = directory}} ->
                            ?vdebug("handle_backup -> backup dir ok", []),
                            %% All well so far...
                            Type = dets:info(D, type),
                            KP   = dets:info(D, keypos),
                            dets_backup(D,
                                        filename:basename(Filename),
                                        BackupDir, Type, KP);
                        {ok, _} ->
                            ?vinfo("handle_backup -> backup dir not a dir",
                                   []),
                            {error, not_a_directory};
                        Error ->
                            ?vinfo("handle_backup -> Error: ~p", [Error]),
                            Error
                    end
            end
    end.

dets_backup(D, Filename, BackupDir, Type, KP) ->
    ?vtrace("dets_backup -> entry with"
            "~n   D:         ~p"
            "~n   Filename:  ~p"
            "~n   BackupDir: ~p", [D, Filename, BackupDir]),
    BackupFile = filename:join(BackupDir, Filename),
    ?vtrace("dets_backup -> "
            "~n   BackupFile: ~p", [BackupFile]),
    Opts = [{file, BackupFile}, {type, Type}, {keypos, KP}],
    case dets:open_file(?BACKUP_DB, Opts) of
        {ok, B} ->
            ?vtrace("dets_backup -> create fun", []),
            F = fun(Arg) ->
                        dets_backup(Arg, start, D, B)
                end,
            dets:safe_fixtable(D, true),
            Res = dets:init_table(?BACKUP_DB, F, [{format, bchunk}]),
            dets:safe_fixtable(D, false),
            ?vtrace("dets_backup -> Res: ~p", [Res]),
            Res;
        Error ->
            ?vinfo("dets_backup -> open_file failed: "
                   "~n   ~p", [Error]),
            Error
    end.


dets_backup(close, _Cont, _D, B) ->
    dets:close(B),
    ok;
dets_backup(read, Cont1, D, B) ->
    case dets:bchunk(D, Cont1) of
        {Cont2, Data} ->
            F = fun(Arg) ->
                        dets_backup(Arg, Cont2, D, B)
                end,
            {Data, F};
        '$end_of_table' ->
            dets:close(B),
            end_of_input;
        Error ->
            Error
    end.


%%%-------------------------------------------------------------------
%%% Internal functions
%%%-------------------------------------------------------------------

handle_register_user(#user{id = Id} = User) ->
    ?vdebug("handle_register_user -> entry with"
	    "~n   User: ~p", [User]),
    case ets:lookup(snmpm_user_table, Id) of
	[] ->
	    ets:insert(snmpm_user_table, User),
	    ok;
	_ ->
	    {error, {already_registered, User}}
    end.

handle_unregister_user(UserId) ->
    ?vdebug("handle_unregister_user -> entry with"
	    "~n   UserId: ~p", [UserId]),
    ets:delete(snmpm_user_table, UserId),
    ok.


handle_register_agent(UserId, TargetName, Config) ->
    ?vdebug("handle_register_agent -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p"
	    "~n   Config:     ~p", [UserId, TargetName, Config]),
    case (catch agent_info(TargetName, user_id)) of
	{error, _} ->
	    ?vtrace("handle_register_agent -> user_id not found in config", []),
	    case ets:lookup(snmpm_user_table, UserId) of
		[#user{default_agent_config = DefConfig}] ->
		    ?vtrace("handle_register_agent -> "
			    "~n   DefConfig: ~p", [DefConfig]),
		    %% First, insert this users default config
		    ?vtrace("handle_register_agent -> store default config", []),
		    do_handle_register_agent(TargetName, DefConfig),
		    %% Second, insert the config for this agent
		    ?vtrace("handle_register_agent -> store config", []),
		    do_handle_register_agent(TargetName, 
					     [{user_id, UserId}|Config]),
		    %% <DIRTY-BACKWARD-COMPATIBILLITY>
		    %% And now for some (backward compatibillity) 
		    %% dirty crossref stuff
		    ?vtrace("handle_register_agent -> lookup address", []),
		    {ok, Addr} = agent_info(TargetName, address),
		    ?vtrace("handle_register_agent -> Addr: ~p, lookup Port", 
			    [Addr]),
		    {ok, Port} = agent_info(TargetName, port),
		    ?vtrace("handle_register_agent -> register cross-ref fix", []),
		    ets:insert(snmpm_agent_table, 
			       {{Addr, Port, target_name}, TargetName}),
		    %% </DIRTY-BACKWARD-COMPATIBILLITY>
		    ok;
		_ ->
		    {error, {not_found, UserId}}
	    end;
	{ok, UserId} ->
	    ?vinfo("[~w] Agent (~p) already registered"
		   "~nwhen"
		   "~n   Agents: ~p", 
		   [UserId, TargetName, which_agents()]),
	    {error, {already_registered, TargetName}};
	{ok, OtherUserId} ->
	    ?vinfo("[~w] Agent (~p) already registered to ~p"
		   "~nwhen"
		   "~n   Agents: ~p", 
		   [UserId, TargetName, OtherUserId, which_agents()]),
	    {error, {already_registered, TargetName, OtherUserId}}
    end.

do_handle_register_agent(_TargetName, []) ->
    ok;
do_handle_register_agent(TargetName, [{Item, Val}|Rest]) ->
    ?vtrace("handle_register_agent -> entry with"
	    "~n   TargetName: ~p"
	    "~n   Item:       ~p"
	    "~n   Val:        ~p"
	    "~n   Rest:       ~p", [TargetName, Item, Val, Rest]),
    case (catch do_update_agent_info(TargetName, Item, Val)) of
	ok ->
	    do_handle_register_agent(TargetName, Rest);
	{error, Reason} ->
	    ?vtrace("handle_register_agent -> failed updating ~p"
		    "~n   Item:   ~p"
		    "~n   Reason: ~p", [Item, Reason]),
	    ets:match_delete(snmpm_agent_table, {TargetName, '_'}),
	    {error, Reason}
    end;
do_handle_register_agent(TargetName, BadConfig) ->
    error_msg("error during agent registration - bad config: ~n~p", 
	      [BadConfig]),
    ets:match_delete(snmpm_agent_table, {TargetName, '_'}),
    {error, {bad_agent_config, TargetName, BadConfig}}.


handle_unregister_agent(UserId, TargetName) ->
    ?vdebug("handle_unregister_agent -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p", [UserId, TargetName]),
    case (catch agent_info(TargetName, user_id)) of
	{ok, UserId} ->
	    {ok, EngineID} = agent_info(TargetName, engine_id),
	    reset_usm_cache(EngineID),
	    %% <DIRTY-BACKWARD-COMPATIBILLITY>
	    %% And now for some (backward compatibillity) 
	    %% dirty crossref stuff
	    {ok, Addr} = agent_info(TargetName, address),
	    {ok, Port} = agent_info(TargetName, port),
	    ets:delete(snmpm_agent_table, {Addr, Port, target_name}),
	    %% </DIRTY-BACKWARD-COMPATIBILLITY>
	    ets:match_delete(snmpm_agent_table, {{TargetName, '_'}, '_'}),
	    ok;
	{ok, OtherUserId} ->
	    {error, {not_owner, OtherUserId}};
	Error ->
	    Error
    end.


handle_update_agent_info(UserId, TargetName, Info) ->
    ?vdebug("handle_update_agent_info -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p"
	    "~n   Info:       ~p", [UserId, TargetName, Info]),
    %% Verify ownership
    case (catch agent_info(TargetName, user_id)) of
	{ok, UserId} -> 
	    handle_update_agent_info(TargetName, Info);
	{ok, OtherUserId} ->
	    {error, {not_owner, OtherUserId}};
	Error ->
	    Error
    end.

handle_update_agent_info(TargetName, Info0) ->
    ?vtrace("handle_update_agent_info -> entry with"
	    "~n   TargetName: ~p"
	    "~n   Info0:      ~p", [TargetName, Info0]),
    %% Verify info
    try verify_agent_info(TargetName, Info0) of
	{ok, Info} -> 
	    do_update_agent_info(TargetName, Info);
	Error ->
	    Error
    catch 
	throw:Error ->
	    Error;
	T:E ->
	    {error, {failed_info_verification, Info0, T, E}}
    end.

handle_update_agent_info(UserId, TargetName, Item, Val) ->
    ?vdebug("handle_update_agent_info -> entry with"
	    "~n   UserId:     ~p"
	    "~n   TargetName: ~p"
	    "~n   Item:       ~p"
	    "~n   Val:        ~p", [UserId, TargetName, Item, Val]),
    handle_update_agent_info(TargetName, [{Item, Val}]).

do_update_agent_info(TargetName, Info) ->
    InsertItem = 
	fun({Item, Val}) -> 
		ets:insert(snmpm_agent_table, {{TargetName, Item}, Val})
	end,
    lists:foreach(InsertItem, Info).

do_update_agent_info(TargetName, Item, Val) ->
    ?vtrace("do_update_agent_info -> entry with"
	    "~n   TargetName: ~p"
	    "~n   Item:       ~p"
	    "~n   Val:       ~p", [TargetName, Item, Val]),
    ets:insert(snmpm_agent_table, {{TargetName, Item}, Val}),
    ok.


handle_register_usm_user(#usm_user{engine_id = EngineID, 
				   name      = Name} = User) ->
    ?vdebug("handle_register_usm_user -> entry with"
	    "~n   User: ~p", [User]),
    Key = usm_key(EngineID, Name),
    case ets:lookup(snmpm_usm_table, Key) of
	[] ->
	    do_update_usm_user_info(Key, User);
	_ ->
	    {error, {already_registered, EngineID, Name}}
    end;
handle_register_usm_user(BadUsmUser) ->
    {error, {bad_usm_user, BadUsmUser}}.
	
handle_unregister_usm_user(EngineID, Name) ->
    ?vdebug("handle_unregister_usm_user -> entry with"
	    "~n   EngineID: ~p"
	    "~n   Name:     ~p", [EngineID, Name]),
    Key = usm_key(EngineID, Name),
    ets:delete(snmpm_usm_table, Key),
    ok.
	

handle_update_usm_user_info(EngineID, Name, Item, Val) ->
    ?vdebug("handle_update_usm_user_info -> entry with"
	    "~n   EngineID: ~p"
	    "~n   Name:     ~p"
	    "~n   Item:     ~p"
	    "~n   Val:      ~p", [EngineID, Name, Item, Val]),
    Key = usm_key(EngineID, Name),
    case ets:lookup(snmpm_usm_table, Key) of
	[] ->
	    {error, not_found};
	[{_Key, User}] ->
	    do_update_usm_user_info(Key, User, Item, Val)
    end.

do_update_usm_user_info(Key, User, sec_name, Val) ->
    %% case verify_usm_user_sec_name(Val) of
    %%     ok ->
    %% 	do_update_usm_user_info(Key, User#usm_user{sec_name = Val});
    %%     _ ->
    %% 	{error, {invalid_usm_sec_name, Val}}
    %% end;
    ok = verify_usm_user_sec_name(Val),
    do_update_usm_user_info(Key, User#usm_user{sec_name = Val});
do_update_usm_user_info(Key, User, auth, Val) 
  when (Val =:= usmNoAuthProtocol) orelse 
       (Val =:= usmHMACMD5AuthProtocol) orelse
       (Val =:= usmHMACSHAAuthProtocol) ->
    do_update_usm_user_info(Key, User#usm_user{auth = Val});
do_update_usm_user_info(_Key, _User, auth, Val) ->
    {error, {invalid_auth_protocol, Val}};
do_update_usm_user_info(Key, 
			#usm_user{auth = usmNoAuthProtocol} = User, 
			auth_key, Val) ->
    case (catch snmp_conf:check_string(Val, any)) of
	ok ->
	    do_update_usm_user_info(Key, User#usm_user{auth_key = Val});
	_ ->
	    {error, {invalid_auth_key, Val}}
    end;
do_update_usm_user_info(Key, 
			#usm_user{auth = usmHMACMD5AuthProtocol} = User, 
			auth_key, Val) 
  when length(Val) =:= 16 ->
    case is_crypto_supported(md5) of
	true -> 
	    do_update_usm_user_info(Key, User#usm_user{auth_key = Val});
	false -> 
	    {error, {unsupported_crypto, md5}}
    end;    
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACMD5AuthProtocol}, 
			auth_key, Val) when is_list(Val) ->
    Len = length(Val),
    {error, {invalid_auth_key_length, usmHMACMD5AuthProtocol, Len}};
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACMD5AuthProtocol}, 
			auth_key, Val) ->
    {error, {invalid_auth_key, usmHMACMD5AuthProtocol, Val}};
do_update_usm_user_info(Key, 
			#usm_user{auth = usmHMACSHAAuthProtocol} = User, 
			auth_key, Val) 
  when length(Val) =:= 20 ->
    case is_crypto_supported(sha) of
	true -> 
	    do_update_usm_user_info(Key, User#usm_user{auth_key = Val});
	false -> 
	    {error, {unsupported_crypto, sha}}
    end;    
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACSHAAuthProtocol}, 
			auth_key, Val) when is_list(Val) ->
    Len = length(Val),
    {error, {invalid_auth_key_length, usmHMACSHAAuthProtocol, Len}};
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACSHAAuthProtocol}, 
			auth_key, Val) ->
    {error, {invalid_auth_key, usmHMACSHAAuthProtocol, Val}};
do_update_usm_user_info(Key, User, priv, Val) 
  when (Val =:= usmNoPrivProtocol) orelse 
       (Val =:= usmDESPrivProtocol) orelse
       (Val =:= usmAesCfb128Protocol) ->
    do_update_usm_user_info(Key, User#usm_user{priv = Val});
do_update_usm_user_info(_Key, _User, priv, Val) ->
    {error, {invalid_priv_protocol, Val}};
do_update_usm_user_info(Key, 
			#usm_user{priv = usmNoPrivProtocol} = User, 
			priv_key, Val) ->
    case (catch snmp_conf:check_string(Val, any)) of
	ok ->
	    do_update_usm_user_info(Key, User#usm_user{priv_key = Val});
	_ ->
	    {error, {invalid_priv_key, Val}}
    end;
do_update_usm_user_info(Key, 
			#usm_user{priv = usmDESPrivProtocol} = User, 
			priv_key, Val) 
  when length(Val) =:= 16 ->
    case is_crypto_supported(des_cbc) of
	true -> 
	    do_update_usm_user_info(Key, User#usm_user{priv_key = Val});
	false -> 
	    {error, {unsupported_crypto, des_cbc}}
    end;    
do_update_usm_user_info(Key, 
			#usm_user{priv = usmAesCfb128Protocoll} = User, 
			priv_key, Val) 
  when length(Val) =:= 16 ->
    case is_crypto_supported(aes_cfb128) of
	true -> 
	    do_update_usm_user_info(Key, User#usm_user{priv_key = Val});
	false -> 
	    {error, {unsupported_crypto, aes_cfb128}}
    end;    
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACSHAAuthProtocol}, 
			priv_key, Val) when is_list(Val) ->
    Len = length(Val),
    {error, {invalid_priv_key_length, usmHMACSHAAuthProtocol, Len}};
do_update_usm_user_info(_Key, 
			#usm_user{auth = usmHMACSHAAuthProtocol}, 
			priv_key, Val) ->
    {error, {invalid_priv_key, usmHMACSHAAuthProtocol, Val}};
do_update_usm_user_info(_Key, _User, Item, Val) ->
    {error, {bad_item, Item, Val}}.

do_update_usm_user_info(Key, User) ->
    ets:insert(snmpm_usm_table, {Key, User}),
    ok.


usm_key(EngineId, Name) ->
    {usmUserTable, EngineId, Name}.


%% ---------------------------------------------------------------------

verify_mandatory(_, []) ->
    ok;
verify_mandatory(Conf, [Mand|Mands]) ->
    case lists:keymember(Mand, 1, Conf) of
	true ->
	    verify_mandatory(Conf, Mands);
	false ->
	    throw({error, {missing_mandatory_config, Mand}})
    end.

verify_invalid(_, []) ->
    ok;
verify_invalid(Conf, [Inv|Invs]) ->
    case lists:member(Inv, Conf) of
	false ->
	    verify_invalid(Conf, Invs);
	true ->
	    throw({error, {illegal_config, Inv}})
    end.


verify_val(user_id, UserId) ->
    {ok, UserId};
verify_val(reg_type, RegType) 
  when (RegType =:= addr_port) orelse (RegType =:= target_name) ->
    {ok, RegType};
verify_val(tdomain = Item, snmpUDPDomain = _Domain) ->
    verify_val(Item, transportDomainUdpIpv4);
verify_val(tdomain, Domain) ->
    case lists:member(Domain, ?SUPPORTED_DOMAINS) of
	true ->
	    {ok, Domain};
	false ->
	    case lists:member(Domain, snmp_conf:all_domains()) of
		true ->
		    error({unsupported_domain, Domain});
		false ->
		    error({unknown_domain, Domain})
	    end
    end;
verify_val(address, {Domain, Addr0}) ->
    case normalize_address(Domain, Addr0) of
	{_A1, _A2, _A3, _A4} = Addr ->
	    {ok, Addr};
	{_A1, _A2, _A3, _A4, _A5, _A6, _A7, _A8} = Addr ->
	    {ok, Addr};
	_ when is_list(Addr0) ->
	    case (catch snmp_conf:check_ip(Addr0)) of
		ok ->
		    {ok, list_to_tuple(Addr0)};
		Err ->
		    Err
	    end;
	_ ->
	    error({bad_address, Addr0})
    end;
verify_val(address, BadAddress) ->
    error({bad_address, BadAddress});
verify_val(port, Port) ->
    case (catch snmp_conf:check_integer(Port, {gt, 0})) of
	ok ->
	    {ok, Port};
	Err ->
	    Err
    end;
verify_val(community, Comm) ->
    case (catch snmp_conf:check_string(Comm)) of
	ok ->
	    {ok, Comm};
	Err ->
	    Err
    end;
verify_val(engine_id, discovery = EngineId) ->
    {ok, EngineId};
verify_val(engine_id, EngineId) ->
    case (catch snmp_conf:check_string(EngineId)) of
	ok ->
	    {ok, EngineId};
	Err ->
	    Err
    end;
verify_val(timeout, Timeout) ->
    (catch snmp_conf:check_timer(Timeout));
verify_val(max_message_size, MMS) ->
    case (catch snmp_conf:check_packet_size(MMS)) of
	ok ->
	    {ok, MMS};
	Err ->
	    Err
    end;
verify_val(version, V) 
  when (V =:= v1) orelse (V =:= v2) orelse (V =:= v3) ->
    {ok, V};
verify_val(version, BadVersion) ->
    error({bad_version, BadVersion});
verify_val(sec_model, Model) ->
    (catch snmp_conf:check_sec_model(Model));
verify_val(sec_name, Name) when is_list(Name) ->
    case (catch snmp_conf:check_string(Name)) of
	ok ->
	    {ok, Name};
	Err ->
	    Err
    end;
verify_val(sec_name, BadName) ->
    error({bad_sec_name, BadName});
verify_val(sec_level, Level) ->
    (catch snmp_conf:check_sec_level(Level));
verify_val(Item, _) ->
    {error, {unknown_item, Item}}.


%%%-------------------------------------------------------------------
%%%
%%% Mini MIB stuff
%%%
%%%-------------------------------------------------------------------

init_mini_mib(MibFiles) ->
    MiniMibs = lists:flatten([do_load_mib(MibFile) || MibFile <- MibFiles]),
    MiniMIB  = remove_duplicates(lists:keysort(1, MiniMibs), []),
    init_mini_mib2(MiniMIB).

remove_duplicates([], Res) -> 
    Res;
remove_duplicates([X,X|T], Res) -> 
    remove_duplicates([X|T], Res);
remove_duplicates([{Oid, Name, Type, _} = X, {Oid, Name, Type, _}|T], Res) -> 
    remove_duplicates([X|T], Res);
remove_duplicates([X|T], Res) -> 
    remove_duplicates(T, [X|Res]).

init_mini_mib2([]) ->
    ok;
init_mini_mib2([{Oid, Name, Type, MibName}|MiniMib]) ->
    ?vtrace("init mini mib -> ~w: ~w [~w] from ~s", 
	    [Name, Oid, Type,MibName ]),    
    ets:insert(snmpm_mib_table, {{mini_mib, Oid}, Name, Type, MibName}),
    init_mini_mib2(MiniMib).


handle_load_mib(Mib) ->
    [{mibs, Mibs0}] = ets:lookup(snmpm_config_table, mibs),
    case lists:member(Mib, Mibs0) of
	true ->
	    {error, already_loaded};
	false ->
	    Mibs = [Mib|Mibs0],
	    case (catch do_load_mib(Mib)) of
		MiniElems when is_list(MiniElems) ->
		    ets:insert(snmpm_config_table, {mibs, Mibs}),
		    update_mini_mib(MiniElems),
		    ok;
		Error ->
		    Error
	    end
    end.

update_mini_mib([]) ->
    ok;
update_mini_mib([{Oid, Name, Type, MibName}|Elems]) ->
    Key = {mini_mib, Oid},
    case ets:lookup(snmpm_mib_table, Key) of
	[{Key, _Name, _Type, _AnotherMibName}] ->
	    %% Already loaded from another mib
	    update_mini_mib(Elems);
	[] ->
	    %% Not yet loaded
	    ?vtrace("update mini mib -> ~w: ~w [~w] from ~s", 
		    [Name, Oid, Type, MibName]),    
	    ets:insert(snmpm_mib_table, {Key, Name, Type, MibName}),
	    update_mini_mib(Elems)
    end.


handle_unload_mib(Mib) ->
    Key = {mib, Mib},
    case ets:lookup(snmpm_mib_table, Key) of
	[{Key, MibName, _MibFile}] ->
	    do_unload_mib(MibName),
	    [{mibs, Mibs0}] = ets:lookup(snmpm_config_table, mibs),
	    Mibs = lists:delete(Mib, Mibs0),
	    ets:insert(snmpm_config_table, {mibs, Mibs}),
	    ets:delete(snmpm_mib_table, Key),
	    ok;
	_ ->
	    {error, not_loaded}
    end.

do_unload_mib(MibName) ->
    Pat  = {{mini_mib, '$1'}, '_', '_', MibName},
    Oids = ets:match(snmpm_mib_table, Pat),
    F    = fun([Oid]) -> ets:delete(snmpm_mib_table, {mini_mib, Oid}) end,
    lists:foreach(F, Oids).
    

do_load_mib(MibFile) ->
    ?vtrace("load mib ~s", [MibFile]),
    F1 = snmp_misc:strip_extension_from_filename(MibFile, ".bin"),
    ActualFileName = lists:append(F1, ".bin"),
    case snmp_misc:read_mib(ActualFileName) of
        {ok, #mib{name = Name, mes = MEs, traps = Traps}} -> 
	    %% Check that the mib was not loaded or loaded
	    %% with a different filename: 
	    %% e.g. /tmp/MYMIB.bin and /tmp/mibs/MYMIB.bin
	    Name1   = mib_name(Name),
	    Pattern = {{mib, '_'}, Name1, '$1'},
	    case ets:match(snmpm_mib_table, Pattern) of
		[] ->
		    
		    Rec = {{mib, MibFile}, Name1, ActualFileName}, 
		    ets:insert(snmpm_mib_table, Rec),
		    init_mini_mib_elems(Name1, MEs++Traps, []);

		%% This means that the mib has already been loaded
		[[ActualFileName]] ->
		    [];

		%% This means that the mib was loaded before,
		%% but under another filename
		[[OtherMibFile]] ->
		    error({already_loaded, MibFile, OtherMibFile})
	    end;
		
        {error, Reason} -> 
	    error({failed_reading_mib, MibFile, Reason})
    end.

mib_name(N) when is_list(N) ->
    list_to_atom(N);
mib_name(N) ->
    N.

init_mini_mib_elems(_, [], Res) -> 
    Res;
init_mini_mib_elems(MibName, 
		    [#me{aliasname = N, 
			 oid       = Oid, 
			 entrytype = variable,
			 asn1_type = #asn1_type{bertype = Type}} | T], Res) ->
    init_mini_mib_elems(MibName, T, [{Oid, N, Type, MibName}|Res]);

init_mini_mib_elems(MibName, 
		    [#me{aliasname = N, 
			 oid       = Oid, 
			 entrytype = table_column,
			 asn1_type = #asn1_type{bertype = Type}}|T], Res) ->
    init_mini_mib_elems(MibName, T, [{Oid, N, Type, MibName}|Res]);

init_mini_mib_elems(MibName, 
		    [#me{aliasname = N, 
			 oid       = Oid,
			 asn1_type = undefined}|T], Res) ->
    init_mini_mib_elems(MibName, T, [{Oid, N, undefined, MibName}|Res]);

init_mini_mib_elems(MibName, 
		    [#notification{trapname = N, 
				   oid      = Oid}|T], Res) ->
    init_mini_mib_elems(MibName, T, [{Oid, N, undefined, MibName}|Res]);

init_mini_mib_elems(MibName, [_|T], Res) ->
    init_mini_mib_elems(MibName, T, Res).



%%----------------------------------------------------------------------

normalize_address(Addr) ->
    normalize_address(snmpUDPDomain, Addr).

normalize_address(snmpUDPDomain, Addr) ->
    normalize_address(transportDomainUdpIpv4, Addr);

normalize_address(Domain, Addr) ->
    case inet:getaddr(Addr, td2fam(Domain)) of
        {ok, Addr2} ->
            Addr2;
        _ when is_list(Addr) ->
	    case (catch snmp_conf:check_ip(Domain, Addr)) of
		ok ->
		    list_to_tuple(Addr);
		_ ->
		    Addr
	    end;
	_ ->
            Addr
    end.

td2fam(transportDomainUdpIpv4) -> inet;
td2fam(transportDomainUdpIpv6) -> inet6.
    

%%----------------------------------------------------------------------

call(Req) ->
    call(Req, infinity).

call(Req, To) ->
    gen_server:call(?SERVER, Req, To).

% cast(Msg) ->
%     gen_server:cast(snmpm_server, Msg).


%%-------------------------------------------------------------------

get_atl_dir(Opts) ->
    get_opt(dir, Opts).

get_atl_type(Opts) ->
    case get_opt(type, Opts, read_write) of
	read_write ->
	    [read,write];
	read ->
	    [read];
	write ->
	    [write]
    end.

get_atl_size(Opts) ->
    get_opt(size, Opts).

get_atl_repair(Opts) ->
    get_opt(repair, Opts, truncate).

get_atl_seqno(Opts) ->
    get_opt(seqno, Opts, false).


%%----------------------------------------------------------------------

get_opt(Key, Opts) ->
    ?d("get option ~w from ~p", [Key, Opts]),
    snmp_misc:get_option(Key, Opts).

get_opt(Key, Opts, Def) ->
    ?d("get option ~w with default ~p from ~p", [Key, Def, Opts]),
    snmp_misc:get_option(Key, Opts, Def).


%%----------------------------------------------------------------------

get_info() ->
    ProcSize = proc_mem(self()),
    CntSz    = tab_size(snmpm_counter_table),
    StatsSz  = tab_size(snmpm_stats_table),
    MibSz    = tab_size(snmpm_mib_table),
    ConfSz   = tab_size(snmpm_config_table),
    AgentSz  = tab_size(snmpm_agent_table),
    UserSz   = tab_size(snmpm_user_table),
    UsmSz    = tab_size(snmpm_usm_table),
    [{process_memory, ProcSize},
     {db_memory, [{counter, CntSz}, 
		  {stats,   StatsSz},
		  {mib,     MibSz}, 
		  {config,  ConfSz},
		  {agent,   AgentSz}, 
		  {user,    UserSz}, 
		  {usm,     UsmSz}]}].

proc_mem(P) when is_pid(P) ->
    case (catch erlang:process_info(P, memory)) of
	{memory, Sz} when is_integer(Sz) ->
	    Sz;
	_ ->
	    undefined
    end.
%% proc_mem(_) ->
%%     undefined.

tab_size(T) ->
    case (catch ets:info(T, memory)) of
	Sz when is_integer(Sz) ->
	    Sz;
	_ ->
	    undefined
    end.


%%----------------------------------------------------------------------

error(Reason) ->
    throw({error, Reason}).


%%----------------------------------------------------------------------

info_msg(F, A) ->
    ?snmpm_info("Config server: " ++ F, A).

warning_msg(F, A) ->
    ?snmpm_warning("Config server: " ++ F, A).

error_msg(F, A) ->
    ?snmpm_error("Config server: " ++ F, A).

%% p(F) ->
%%     p(F, []).

%% p(F, A) ->
%%     io:format("~w:" ++ F ++ "~n", [?MODULE | A]).