%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
-module(inet_config).
-include("inet_config.hrl").
-include("inet.hrl").
-import(lists, [foreach/2, member/2, reverse/1]).
%% Avoid warning for local function error/2 clashing with autoimported BIF.
-compile({no_auto_import,[error/2]}).
-export([init/0]).
-export([do_load_resolv/2]).
%%
%% Must be called after inet_db:start
%%
%% Order in which to load inet_db data:
%% 1. Hostname (possibly derive domain and search)
%% 2. OS default /etc/resolv.conf, Windows registry etc
%% a) Hosts database
%% b) Resolver options
%% 3. Config (kernel app)
%% 4. Root (otp root)
%% 5. Home (user inetrc)
%%
%%
-spec init() -> 'ok'.
init() ->
set_hostname(),
%% Note: In shortnames (or non-distributed) mode we don't need to know
%% our own domain name. In longnames mode we do and we can't rely on
%% the user to provide it (by means of inetrc), so we need to look
%% for it ourselves.
OsType = os:type(),
do_load_resolv(OsType, erl_dist_mode()),
case OsType of
{unix,Type} ->
if Type =:= linux ->
%% It may be the case that the domain name was not set
%% because the hostname was short. But NOW we can look it
%% up and get the long name and the domain name from it.
%% FIXME: The second call to set_hostname will insert
%% a duplicate entry in the search list.
case inet_db:res_option(domain) of
"" ->
case inet:gethostbyname(inet_db:gethostname()) of
{ok,#hostent{h_name = []}} ->
ok;
{ok,#hostent{h_name = HostName}} ->
set_hostname({ok,HostName});
_ ->
ok
end;
_ ->
ok
end;
true -> ok
end,
add_dns_lookup(inet_db:res_option(lookup));
_ ->
ok
end,
%% Read inetrc file, if it exists.
{RcFile,CfgFiles,CfgList} = read_rc(),
%% Possibly read config files or system registry
lists:foreach(fun({file,hosts,File}) ->
load_hosts(File, unix);
({file,Func,File}) ->
load_resolv(File, Func);
({registry,win32}) ->
case OsType of
{win32,WinType} ->
win32_load_from_registry(WinType);
_ ->
error("cannot read win32 system registry~n", [])
end
end, CfgFiles),
%% Add inetrc config entries
case inet_db:add_rc_list(CfgList) of
ok -> ok;
_ -> error("syntax error in ~ts~n", [RcFile])
end,
%% Set up a resolver configuration file for inet_res,
%% unless that already has been done
case OsType of
{unix,_} ->
%% The Etc variable enables us to run tests with other
%% configuration files than the normal ones
Etc = os:getenv("ERL_INET_ETC_DIR", ?DEFAULT_ETC),
case inet_db:res_option(resolv_conf) of
undefined ->
inet_db:res_option(
resolv_conf_name,
filename:join(Etc, ?DEFAULT_RESOLV));
_ -> ok
end,
case inet_db:res_option(hosts_file) of
undefined ->
inet_db:res_option(
hosts_file_name,
filename:join(Etc, ?DEFAULT_HOSTS));
_ -> ok
end;
_ -> ok
end.
erl_dist_mode() ->
case init:get_argument(sname) of
{ok,[[_SName]]} -> shortnames;
_ ->
case init:get_argument(name) of
{ok,[[_Name]]} -> longnames;
_ -> nonames
end
end.
do_load_resolv({unix,Type}, longnames) ->
%% The Etc variable enables us to run tests with other
%% configuration files than the normal ones
Etc = os:getenv("ERL_INET_ETC_DIR", ?DEFAULT_ETC),
load_resolv(filename:join(Etc, ?DEFAULT_RESOLV), resolv),
case Type of
freebsd -> %% we may have to check version (2.2.2)
load_resolv(filename:join(Etc,"host.conf"), host_conf_freebsd);
'bsd/os' ->
load_resolv(filename:join(Etc,"irs.conf"), host_conf_bsdos);
sunos ->
case os:version() of
{Major,_,_} when Major >= 5 ->
load_resolv(filename:join(Etc,"nsswitch.conf"),
nsswitch_conf);
_ ->
ok
end;
netbsd ->
case os:version() of
{Major,Minor,_} when Major >= 1, Minor >= 4 ->
load_resolv(filename:join(Etc,"nsswitch.conf"),
nsswitch_conf);
_ ->
ok
end;
linux ->
case load_resolv(filename:join(Etc,"host.conf"),
host_conf_linux) of
ok ->
ok;
_ ->
load_resolv(filename:join(Etc,"nsswitch.conf"),
nsswitch_conf)
end;
_ ->
ok
end,
inet_db:set_lookup([native]);
do_load_resolv({win32,Type}, longnames) ->
win32_load_from_registry(Type),
inet_db:set_lookup([native]);
do_load_resolv(_, _) ->
inet_db:set_lookup([native]).
add_dns_lookup(L) ->
case lists:member(dns,L) of
true -> ok;
_ ->
case application:get_env(kernel,inet_dns_when_nis) of
{ok,true} ->
add_dns_lookup(L,[]);
_ ->
ok
end
end.
add_dns_lookup([yp|T],Acc) ->
add_dns_lookup(T,[yp,dns|Acc]);
add_dns_lookup([H|T],Acc) ->
add_dns_lookup(T,[H|Acc]);
add_dns_lookup([],Acc) ->
inet_db:set_lookup(reverse(Acc)).
%%
%% Set the hostname (SHORT)
%% If hostname is long use the suffix as default domain
%% and initalize the search option with the parts of domain
%%
set_hostname() ->
case inet_udp:open(0,[]) of
{ok,U} ->
Res = inet:gethostname(U),
inet_udp:close(U),
set_hostname(Res);
_ ->
set_hostname({ok, []})
end.
set_hostname({ok,Name}) when length(Name) > 0 ->
{Host, Domain} = lists:splitwith(fun($.) -> false;
(_) -> true
end, Name),
inet_db:set_hostname(Host),
set_search_dom(Domain);
set_hostname({ok,[]}) ->
inet_db:set_hostname("nohost"),
set_search_dom("nodomain").
set_search_dom([$.|Domain]) ->
%% leading . not removed by dropwhile above.
inet_db:set_domain(Domain),
inet_db:ins_search(Domain),
ok;
set_search_dom([]) ->
ok;
set_search_dom(Domain) ->
inet_db:set_domain(Domain),
inet_db:ins_search(Domain),
ok.
%%
%% Load resolver data
%%
load_resolv(File, Func) ->
case get_file(File) of
{ok,Bin} ->
case inet_parse:Func(File, {chars, Bin}) of
{ok, Ls} ->
inet_db:add_rc_list(Ls);
{error, Reason} ->
error("parse error in file ~ts: ~p", [File, Reason])
end;
Error ->
warning("file not found ~ts: ~p~n", [File, Error])
end.
%%
%% Load a UNIX hosts file
%%
load_hosts(File,Os) ->
case get_file(File) of
{ok,Bin} ->
case inet_parse:hosts(File,{chars,Bin}) of
{ok, Ls} ->
foreach(
fun({IP, Name, Aliases}) ->
inet_db:add_host(IP, [Name|Aliases]) end,
Ls);
{error, Reason} ->
error("parse error in file ~ts: ~p", [File, Reason])
end;
Error ->
case Os of
unix ->
error("file not found ~ts: ~p~n", [File, Error]);
_ ->
%% for windows or nt the hosts file is not always there
%% and we don't require it
ok
end
end.
%%
%% Load resolver data from Windows registry
%%
win32_load_from_registry(Type) ->
%% The TcpReg variable enables us to run tests with other registry configurations than
%% the normal ones
TcpReg = os:getenv("ERL_INET_ETC_DIR", ""),
{ok, Reg} = win32reg:open([read]),
{TcpIp,HFileKey} =
case Type of
nt ->
case TcpReg of
[] ->
{"\\hklm\\system\\CurrentControlSet\\Services\\TcpIp\\Parameters",
"DataBasePath" };
Other ->
{Other,"DataBasePath"}
end;
windows ->
case TcpReg of
[] ->
{"\\hklm\\system\\CurrentControlSet\\Services\\VxD\\MSTCP",
"LMHostFile" };
Other ->
{Other,"LMHostFile"}
end
end,
Result =
case win32reg:change_key(Reg,TcpIp) of
ok ->
win32_load1(Reg,Type,HFileKey);
{error, _Reason} ->
error("Failed to locate TCP/IP parameters (is TCP/IP installed)?",
[])
end,
win32reg:close(Reg),
Result.
win32_load1(Reg,Type,HFileKey) ->
Names = [HFileKey, "Domain", "DhcpDomain",
"EnableDNS", "NameServer", "SearchList"],
case win32_get_strings(Reg, Names) of
[DBPath0, Domain, DhcpDomain,
_EnableDNS, NameServers0, Search] ->
inet_db:set_domain(
case Domain of "" -> DhcpDomain; _ -> Domain end),
NameServers = win32_split_line(NameServers0,Type),
AddNs = fun(Addr) ->
case inet_parse:address(Addr) of
{ok, Address} ->
inet_db:add_ns(Address);
{error, _} ->
error("Bad TCP/IP address in registry", [])
end
end,
foreach(AddNs, NameServers),
Searches0 = win32_split_line(Search,Type),
Searches = case member(Domain, Searches0) of
true -> Searches0;
false -> [Domain|Searches0]
end,
foreach(fun(D) -> inet_db:add_search(D) end, Searches),
if Type =:= nt ->
DBPath = win32reg:expand(DBPath0),
load_hosts(filename:join(DBPath, "hosts"),nt);
Type =:= windows ->
load_hosts(filename:join(DBPath0,""),windows)
end,
%% Maybe activate this later as an optimization
%% For now we use native always as the SAFE way
%% case NameServers of
%% [] -> inet_db:set_lookup([native, file]);
%% _ -> inet_db:set_lookup([dns, file, native])
%% end;
true;
{error, _Reason} ->
error("Failed to read TCP/IP parameters from registry", [])
end.
win32_split_line(Line,nt) -> inet_parse:split_line(Line);
win32_split_line(Line,windows) -> string:lexemes(Line, ",").
win32_get_strings(Reg, Names) ->
win32_get_strings(Reg, Names, []).
win32_get_strings(Reg, [Name|Rest], Result) ->
case win32reg:value(Reg, Name) of
{ok, Value} when is_list(Value) ->
win32_get_strings(Reg, Rest, [Value|Result]);
{ok, _NotString} ->
{error, not_string};
{error, _Reason} ->
win32_get_strings(Reg, Rest, [""|Result])
end;
win32_get_strings(_, [], Result) ->
lists:reverse(Result).
read_rc() ->
{RcFile,CfgList} = read_inetrc(),
case extract_cfg_files(CfgList, [], []) of
{CfgFiles,CfgList1} ->
{RcFile,CfgFiles,CfgList1};
error ->
{error,[],[]}
end.
extract_cfg_files([E = {file,Type,_File} | Es], CfgFiles, CfgList) ->
extract_cfg_files1(Type, E, Es, CfgFiles, CfgList);
extract_cfg_files([E = {registry,Type} | Es], CfgFiles, CfgList) ->
extract_cfg_files1(Type, E, Es, CfgFiles, CfgList);
extract_cfg_files([E | Es], CfgFiles, CfgList) ->
extract_cfg_files(Es, CfgFiles, [E | CfgList]);
extract_cfg_files([], CfgFiles, CfgList) ->
{reverse(CfgFiles),reverse(CfgList)}.
extract_cfg_files1(Type, E, Es, CfgFiles, CfgList) ->
case valid_type(Type) of
true ->
extract_cfg_files(Es, [E | CfgFiles], CfgList);
false ->
error("invalid config value ~w in inetrc~n", [Type]),
error
end.
valid_type(resolv) -> true;
valid_type(host_conf_freebsd) -> true;
valid_type(host_conf_bsdos) -> true;
valid_type(host_conf_linux) -> true;
valid_type(nsswitch_conf) -> true;
valid_type(hosts) -> true;
valid_type(win32) -> true;
valid_type(_) -> false.
read_inetrc() ->
case application:get_env(inetrc) of
{ok,File} ->
try_get_rc(File);
_ ->
case os:getenv("ERL_INETRC") of
false ->
{nofile,[]};
File ->
try_get_rc(File)
end
end.
try_get_rc(File) ->
case get_rc(File) of
error -> {nofile,[]};
Ls -> {File,Ls}
end.
get_rc(File) ->
case get_file(File) of
{ok,Bin} ->
case parse_inetrc(Bin) of
{ok,Ls} ->
Ls;
_Error ->
error("parse error in ~ts~n", [File]),
error
end;
_Error ->
error("file ~ts not found~n", [File]),
error
end.
%% XXX Check if we really need to prim load the stuff
get_file(File) ->
case erl_prim_loader:get_file(File) of
{ok,Bin,_} -> {ok,Bin};
Error -> Error
end.
error(Fmt, Args) ->
error_logger:error_msg("inet_config: " ++ Fmt, Args).
warning(Fmt, Args) ->
case application:get_env(kernel,inet_warnings) of
%{ok,silent} -> ok;
{ok,on} ->
error_logger:info_msg("inet_config:" ++ Fmt, Args);
_ ->
ok
end.
%%
%% Parse inetrc, i.e. make a binary of a term list.
%% The extra newline is to let the user ignore the whitespace !!!
%% Ignore leading whitespace before a token (due to bug in erl_scan) !
%%
parse_inetrc(Bin) ->
case file_binary_to_list(Bin) of
{ok, String} ->
parse_inetrc(String ++ "\n", 1, []);
error ->
{error, 'bad_encoding'}
end.
parse_inetrc_skip_line([], _Line, Ack) ->
{ok, reverse(Ack)};
parse_inetrc_skip_line([$\n|Str], Line, Ack) ->
parse_inetrc(Str, Line+1, Ack);
parse_inetrc_skip_line([_|Str], Line, Ack) ->
parse_inetrc_skip_line(Str, Line, Ack).
parse_inetrc([$%|Str], Line, Ack) ->
parse_inetrc_skip_line(Str, Line, Ack);
parse_inetrc([$\s|Str], Line, Ack) ->
parse_inetrc(Str, Line, Ack);
parse_inetrc([$\n |Str], Line, Ack) ->
parse_inetrc(Str, Line+1, Ack);
parse_inetrc([$\t|Str], Line, Ack) ->
parse_inetrc(Str, Line, Ack);
parse_inetrc([], _, Ack) ->
{ok, reverse(Ack)};
%% The clauses above are here due to a bug in erl_scan (OTP-1449).
parse_inetrc(Str, Line, Ack) ->
case erl_scan:tokens([], Str, Line) of
{done, {ok, Tokens, EndLine}, MoreChars} ->
case erl_parse:parse_term(Tokens) of
{ok, Term} ->
parse_inetrc(MoreChars, EndLine, [Term|Ack]);
Error ->
{error, {'parse_inetrc', Error}}
end;
{done, {eof, _}, _} ->
{ok, reverse(Ack)};
{done, Error, _} ->
{error, {'scan_inetrc', Error}};
{more, _} -> %% Bug in erl_scan !!
{error, {'scan_inetrc', {eof, Line}}}
end.
file_binary_to_list(Bin) ->
Enc = case epp:read_encoding_from_binary(Bin) of
none -> epp:default_encoding();
Encoding -> Encoding
end,
case catch unicode:characters_to_list(Bin, Enc) of
String when is_list(String) ->
{ok, String};
_ ->
error
end.
