From 68aac2e50559d9d67b1c2152166f8f2e08b03880 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Holger=20Wei=C3=9F?= Date: Tue, 2 Jun 2015 16:12:15 +0200 Subject: [PATCH] inet_res: Make host name lookups case-insensitive This partly reverts commit 8152505ea3793037984a7f3349ac95cc20c4e44c. --- lib/kernel/src/inet_db.erl | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) diff --git a/lib/kernel/src/inet_db.erl b/lib/kernel/src/inet_db.erl index 2ebdc0f554b8..ee7dfaeb3d28 100644 --- a/lib/kernel/src/inet_db.erl +++ b/lib/kernel/src/inet_db.erl @@ -632,20 +632,22 @@ make_hostent(Name, Datas, Aliases, Type) -> hostent_by_domain(Domain, Type) -> ?dbg("hostent_by_domain: ~p~n", [Domain]), - hostent_by_domain(stripdot(Domain), [], Type). + hostent_by_domain(stripdot(Domain), [], [], Type). -hostent_by_domain(Domain, Aliases, Type) -> +hostent_by_domain(Domain, Aliases, LAliases, Type) -> case lookup_type(Domain, Type) of [] -> case lookup_cname(Domain) of [] -> {error, nxdomain}; [CName | _] -> - case lists:member(CName, [Domain | Aliases]) of + LDomain = tolower(Domain), + case lists:member(CName, [LDomain | LAliases]) of true -> {error, nxdomain}; false -> - hostent_by_domain(CName, [Domain | Aliases], Type) + hostent_by_domain(CName, [Domain | Aliases], + [LDomain | LAliases], Type) end end; Addrs -> @@ -670,24 +672,26 @@ lookup_rr(Domain, Class, Type) -> %% match data field directly and cache RRs. %% res_hostent_by_domain(Domain, Type, Rec) -> - res_cache_answer(Rec), - RRs = Rec#dns_rec.anlist, + RRs = lists:map(fun lower_rr/1, Rec#dns_rec.anlist), + res_cache_answer(Rec#dns_rec{anlist = RRs}), ?dbg("res_hostent_by_domain: ~p - ~p~n", [Domain, RRs]), - res_hostent_by_domain(stripdot(Domain), [], Type, RRs). + res_hostent_by_domain(stripdot(Domain), [], [], Type, RRs). -res_hostent_by_domain(Domain, Aliases, Type, RRs) -> - case res_lookup_type(Domain, Type, RRs) of +res_hostent_by_domain(Domain, Aliases, LAliases, Type, RRs) -> + LDomain = tolower(Domain), + case res_lookup_type(LDomain, Type, RRs) of [] -> - case res_lookup_type(Domain, ?S_CNAME, RRs) of + case res_lookup_type(LDomain, ?S_CNAME, RRs) of [] -> {error, nxdomain}; [CName | _] -> - case lists:member(CName, [Domain | Aliases]) of + case lists:member(tolower(CName), [LDomain | LAliases]) of true -> {error, nxdomain}; false -> res_hostent_by_domain(CName, [Domain | Aliases], - Type, RRs) + [LDomain | LAliases], Type, + RRs) end end; Addrs -> @@ -720,7 +724,8 @@ gethostbyaddr(IP) -> %% res_gethostbyaddr(IP, Rec) -> {ok, {IP1, HType, HLen}} = dnt(IP), - res_cache_answer(Rec), + RRs = lists:map(fun lower_rr/1, Rec#dns_rec.anlist), + res_cache_answer(Rec#dns_rec{anlist = RRs}), ent_gethostbyaddr(Rec#dns_rec.anlist, IP1, HType, HLen). ent_gethostbyaddr(RRs, IP, AddrType, Length) -> @@ -1378,7 +1383,7 @@ times() -> %% lookup and remove old entries do_lookup_rr(Domain, Class, Type) -> - match_rr(#dns_rr{domain = Domain, class = Class,type = Type, + match_rr(#dns_rr{domain = tolower(Domain), class = Class,type = Type, cnt = '_', tm = '_', ttl = '_', bm = '_', func = '_', data = '_'}). @@ -1400,6 +1405,11 @@ filter_rr([RR | RRs], Time) -> [RR | filter_rr(RRs, Time)]; filter_rr([], _Time) -> []. +%% Lower case the domain name before storage. +%% +lower_rr(#dns_rr{domain=Domain}=RR) when is_list(Domain) -> + RR#dns_rr { domain = tolower(Domain) }; +lower_rr(RR) -> RR. %% %% Case fold upper-case to lower-case according to RFC 4343