summaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/catlfish.erl226
-rw-r--r--src/v1.erl61
-rw-r--r--src/x509.erl175
3 files changed, 318 insertions, 144 deletions
diff --git a/src/catlfish.erl b/src/catlfish.erl
index 2fd9dc7..3b81baa 100644
--- a/src/catlfish.erl
+++ b/src/catlfish.erl
@@ -2,7 +2,7 @@
%%% See LICENSE for licensing information.
-module(catlfish).
--export([add_chain/2, entries/2, entry_and_proof/2]).
+-export([add_chain/3, entries/2, entry_and_proof/2]).
-export([known_roots/0, update_known_roots/0]).
-export([init_cache_table/0]).
-include_lib("eunit/include/eunit.hrl").
@@ -21,53 +21,89 @@
-record(timestamped_entry, {timestamp :: integer(),
entry_type :: entry_type(),
- signed_entry :: binary(),
+ signed_entry :: signed_x509_entry() |
+ signed_precert_entry(),
extensions = <<>> :: binary()}).
-type timestamped_entry() :: #timestamped_entry{}.
--spec serialise(mtl() | timestamped_entry()) -> binary().
-serialise(#timestamped_entry{timestamp = Timestamp} = E) ->
- list_to_binary(
- [<<Timestamp:64>>,
- serialise_entry_type(E#timestamped_entry.entry_type),
- encode_tls_vector(E#timestamped_entry.signed_entry, 3),
- encode_tls_vector(E#timestamped_entry.extensions, 2)]);
+-record(signed_x509_entry, {asn1_cert :: binary()}).
+-type signed_x509_entry() :: #signed_x509_entry{}.
+-record(signed_precert_entry, {issuer_key_hash :: binary(),
+ tbs_certificate :: binary()}).
+-type signed_precert_entry() :: #signed_precert_entry{}.
+
+-spec serialise(mtl() | timestamped_entry() |
+ signed_x509_entry() | signed_precert_entry()) -> binary().
+%% @doc Serialise a MerkleTreeLeaf as per RFC6962 Section 3.4.
serialise(#mtl{leaf_version = LeafVersion,
leaf_type = LeafType,
entry = TimestampedEntry}) ->
list_to_binary(
[serialise_leaf_version(LeafVersion),
serialise_leaf_type(LeafType),
- serialise(TimestampedEntry)]).
+ serialise(TimestampedEntry)]);
+%% @doc Serialise a TimestampedEntry as per RFC6962 Section 3.4.
+serialise(#timestamped_entry{timestamp = Timestamp,
+ entry_type = EntryType,
+ signed_entry = SignedEntry,
+ extensions = Extensions}) ->
+ list_to_binary(
+ [<<Timestamp:64>>,
+ serialise_entry_type(EntryType),
+ serialise(SignedEntry),
+ encode_tls_vector(Extensions, 2)]);
+%% @doc Serialise an ASN1.Cert as per RFC6962 Section 3.1.
+serialise(#signed_x509_entry{asn1_cert = Cert}) ->
+ encode_tls_vector(Cert, 3);
+%% @doc Serialise a PreCert as per RFC6962 Section 3.2.
+serialise(#signed_precert_entry{
+ issuer_key_hash = IssuerKeyHash,
+ tbs_certificate = TBSCertificate}) when is_binary(IssuerKeyHash),
+ size(IssuerKeyHash) == 32 ->
+ list_to_binary(
+ [IssuerKeyHash,
+ encode_tls_vector(TBSCertificate, 3)]).
serialise_leaf_version(v1) ->
<<0:8>>;
serialise_leaf_version(v2) ->
<<1:8>>.
+deserialise_leaf_version(<<0:8>>) ->
+ v1;
+deserialise_leaf_version(<<1:8>>) ->
+ v2.
serialise_leaf_type(timestamped_entry) ->
<<0:8>>.
-%% serialise_leaf_type(_) ->
-%% <<>>.
+deserialise_leaf_type(<<0:8>>) ->
+ timestamped_entry.
serialise_entry_type(x509_entry) ->
<<0:16>>;
serialise_entry_type(precert_entry) ->
<<1:16>>.
+deserialise_entry_type(<<0:16>>) ->
+ x509_entry;
+deserialise_entry_type(<<1:16>>) ->
+ precert_entry.
serialise_signature_type(certificate_timestamp) ->
<<0:8>>;
serialise_signature_type(tree_hash) ->
<<1:8>>.
+%% deserialise_signature_type(<<0:8>>) ->
+%% certificate_timestamp;
+%% deserialise_signature_type(<<1:8>>) ->
+%% tree_hash.
-build_mtl(Timestamp, LeafCert) ->
- TSE = #timestamped_entry{timestamp = Timestamp,
- entry_type = x509_entry,
- signed_entry = LeafCert},
- MTL = #mtl{leaf_version = v1,
- leaf_type = timestamped_entry,
- entry = TSE},
- serialise(MTL).
+%% build_mtl(Timestamp, LeafCert) ->
+%% TSE = #timestamped_entry{timestamp = Timestamp,
+%% entry_type = x509_entry,
+%% signed_entry = LeafCert},
+%% MTL = #mtl{leaf_version = v1,
+%% leaf_type = timestamped_entry,
+%% entry = TSE},
+%% serialise(MTL).
calc_sct(TimestampedEntry) ->
plop:serialise(plop:spt(list_to_binary([<<?PROTOCOL_VERSION:8>>,
@@ -86,37 +122,48 @@ get_sct(Hash, TimestampedEntry) ->
SCT
end;
_ ->
- SCT = calc_sct(TimestampedEntry)
+ calc_sct(TimestampedEntry)
end.
--spec add_chain(binary(), [binary()]) -> nonempty_string().
-add_chain(LeafCert, CertChain) ->
+-spec add_chain(binary(), [binary()], normal|precert) -> nonempty_string().
+add_chain(LeafCert, CertChain, Type) ->
EntryHash = crypto:hash(sha256, [LeafCert | CertChain]),
+ EntryType = case Type of
+ normal -> x509_entry;
+ precert -> precert_entry
+ end,
{TimestampedEntry, Hash} =
case plop:get(EntryHash) of
notfound ->
Timestamp = plop:generate_timestamp(),
- TSE = #timestamped_entry{timestamp = Timestamp,
- entry_type = x509_entry,
- signed_entry = LeafCert},
- MTL = #mtl{leaf_version = v1,
- leaf_type = timestamped_entry,
- entry = TSE},
- MTLHash = ht:leaf_hash(serialise(MTL)),
- ok = plop:add(
- serialise_logentry(Timestamp, LeafCert, CertChain),
- MTLHash,
- EntryHash),
+ TSE = timestamped_entry(Timestamp, EntryType, LeafCert, CertChain),
+ MTLText = serialise(#mtl{leaf_version = v1,
+ leaf_type = timestamped_entry,
+ entry = TSE}),
+ MTLHash = ht:leaf_hash(MTLText),
+ ExtraData =
+ case Type of
+ normal -> CertChain;
+ precert -> [LeafCert | CertChain]
+ end,
+ LogEntry =
+ list_to_binary(
+ [encode_tls_vector(MTLText, 4),
+ encode_tls_vector(
+ encode_tls_vector(
+ list_to_binary(
+ [encode_tls_vector(C, 3) || C <- ExtraData]),
+ 3),
+ 4)]),
+ ok = plop:add(LogEntry, MTLHash, EntryHash),
{TSE, MTLHash};
- {_Index, MTLHash, Entry} ->
- <<Timestamp:64, _LogEntry/binary>> = Entry,
- %% TODO: Perform a costly db consistency check against
- %% unpacked LogEntry (w/ LeafCert and CertChain)
- {#timestamped_entry{timestamp = Timestamp,
- entry_type = x509_entry,
- signed_entry = LeafCert},
- MTLHash}
+ {_Index, MTLHash, DBEntry} ->
+ {MTLText, _ExtraData} = unpack_entry(DBEntry),
+ MTL = deserialise_mtl(MTLText),
+ MTLText = serialise(MTL), % verify FIXME: remove
+ {MTL#mtl.entry, MTLHash}
end,
+
SCT_sig = get_sct(Hash, TimestampedEntry),
{[{sct_version, ?PROTOCOL_VERSION},
{id, base64:encode(plop:get_logid())},
@@ -124,15 +171,73 @@ add_chain(LeafCert, CertChain) ->
{extensions, base64:encode(<<>>)},
{signature, base64:encode(SCT_sig)}]}.
--spec serialise_logentry(integer(), binary(), [binary()]) -> binary().
-serialise_logentry(Timestamp, LeafCert, CertChain) ->
- list_to_binary(
- [<<Timestamp:64>>,
- list_to_binary(
- [encode_tls_vector(LeafCert, 3),
- encode_tls_vector(
- list_to_binary(
- [encode_tls_vector(X, 3) || X <- CertChain]), 3)])]).
+-spec timestamped_entry(integer(), entry_type(), binary(), binary()) ->
+ timestamped_entry().
+timestamped_entry(Timestamp, EntryType, LeafCert, CertChain) ->
+ SignedEntry =
+ case EntryType of
+ x509_entry ->
+ #signed_x509_entry{asn1_cert = LeafCert};
+ precert_entry ->
+ {DetoxedLeafTBSCert, IssuerKeyHash} =
+ x509:detox(LeafCert, CertChain),
+ #signed_precert_entry{
+ issuer_key_hash = IssuerKeyHash,
+ tbs_certificate = DetoxedLeafTBSCert}
+ end,
+ #timestamped_entry{timestamp = Timestamp,
+ entry_type = EntryType,
+ signed_entry = SignedEntry}.
+
+%% -spec serialise_logentry(integer(), binary(), [binary()]) -> binary().
+%% serialise_logentry(Timestamp, LeafCert, CertChain) ->
+%% list_to_binary(
+%% [<<Timestamp:64>>,
+%% list_to_binary(
+%% [encode_tls_vector(LeafCert, 3),
+%% encode_tls_vector(
+%% list_to_binary(
+%% [encode_tls_vector(X, 3) || X <- CertChain]), 3)])]).
+
+-spec deserialise_mtl(binary()) -> mtl().
+deserialise_mtl(Data) ->
+ <<LeafVersionBin:1/binary,
+ LeafTypeBin:1/binary,
+ TimestampedEntryBin/binary>> = Data,
+ #mtl{leaf_version = deserialise_leaf_version(LeafVersionBin),
+ leaf_type = deserialise_leaf_type(LeafTypeBin),
+ entry = deserialise_timestampedentry(TimestampedEntryBin)}.
+
+-spec deserialise_timestampedentry(binary()) -> timestamped_entry().
+deserialise_timestampedentry(Data) ->
+ <<Timestamp:64, EntryTypeBin:2/binary, RestData/binary>> = Data,
+ EntryType = deserialise_entry_type(EntryTypeBin),
+ {SignedEntry, ExtensionsBin} =
+ case EntryType of
+ x509_entry ->
+ deserialise_signed_x509_entry(RestData);
+ precert_entry ->
+ deserialise_signed_precert_entry(RestData)
+ end,
+ {Extensions, <<>>} = decode_tls_vector(ExtensionsBin, 2),
+ #timestamped_entry{timestamp = Timestamp,
+ entry_type = EntryType,
+ signed_entry = SignedEntry,
+ extensions = Extensions}.
+
+-spec deserialise_signed_x509_entry(binary()) -> {signed_x509_entry(), binary()}.
+deserialise_signed_x509_entry(Data) ->
+ {E, D} = decode_tls_vector(Data, 3),
+ {#signed_x509_entry{asn1_cert = E}, D}.
+
+-spec deserialise_signed_precert_entry(binary()) ->
+ {signed_precert_entry(), binary()}.
+deserialise_signed_precert_entry(Data) ->
+ <<IssuerKeyHash:32/binary, RestData/binary>> = Data,
+ {TBSCertificate, RestData2} = decode_tls_vector(RestData, 3),
+ {#signed_precert_entry{issuer_key_hash = IssuerKeyHash,
+ tbs_certificate = TBSCertificate},
+ RestData2}.
-spec entries(non_neg_integer(), non_neg_integer()) -> list().
entries(Start, End) ->
@@ -142,10 +247,9 @@ entries(Start, End) ->
entry_and_proof(Index, TreeSize) ->
case plop:inclusion_and_entry(Index, TreeSize) of
{ok, Entry, Path} ->
- {Timestamp, LeafCertVector, CertChainVector} = unpack_entry(Entry),
- MTL = build_mtl(Timestamp, LeafCertVector),
+ {MTL, ExtraData} = unpack_entry(Entry),
{[{leaf_input, base64:encode(MTL)},
- {extra_data, base64:encode(CertChainVector)},
+ {extra_data, base64:encode(ExtraData)},
{audit_path, [base64:encode(X) || X <- Path]}]};
{notfound, Msg} ->
{[{success, false},
@@ -161,20 +265,20 @@ init_cache_table() ->
ets:new(?CACHE_TABLE, [set, public, named_table]).
%% Private functions.
+-spec unpack_entry(binary()) -> {binary(), binary()}.
unpack_entry(Entry) ->
- <<Timestamp:64, LogEntry/binary>> = Entry,
- {LeafCertVector, CertChainVector} = decode_tls_vector(LogEntry, 3),
- {Timestamp, LeafCertVector, CertChainVector}.
+ {MTL, Rest} = decode_tls_vector(Entry, 4),
+ {ExtraData, <<>>} = decode_tls_vector(Rest, 4),
+ {MTL, ExtraData}.
-spec x_entries([{non_neg_integer(), binary(), binary()}]) -> list().
x_entries([]) ->
[];
x_entries([H|T]) ->
{_Index, _Hash, Entry} = H,
- {Timestamp, LeafCertVector, CertChainVector} = unpack_entry(Entry),
- MTL = build_mtl(Timestamp, LeafCertVector),
- [{[{leaf_input, base64:encode(MTL)}, {extra_data, base64:encode(CertChainVector)}]} |
- x_entries(T)].
+ {MTL, ExtraData} = unpack_entry(Entry),
+ [{[{leaf_input, base64:encode(MTL)},
+ {extra_data, base64:encode(ExtraData)}]} | x_entries(T)].
-spec encode_tls_vector(binary(), non_neg_integer()) -> binary().
encode_tls_vector(Binary, LengthLen) ->
diff --git a/src/v1.erl b/src/v1.erl
index 006990d..6d13541 100644
--- a/src/v1.erl
+++ b/src/v1.erl
@@ -9,34 +9,10 @@
%% Public functions, i.e. part of URL.
request(post, "ct/v1/add-chain", Input) ->
- case (catch mochijson2:decode(Input)) of
- {error, E} ->
- html("add-chain: bad input:", E);
- {struct, [{<<"chain">>, ChainBase64}]} ->
- case (catch [base64:decode(X) || X <- ChainBase64]) of
- {'EXIT', _} ->
- html("add-chain: invalid base64-encoded chain: ",
- [ChainBase64]);
- [LeafCert | CertChain] ->
- Roots = catlfish:known_roots(),
- case x509:normalise_chain(Roots, [LeafCert|CertChain]) of
- {ok, [Leaf | Chain]} ->
- lager:info("adding ~p",
- [x509:cert_string(LeafCert)]),
- success(catlfish:add_chain(Leaf, Chain));
- {error, Reason} ->
- lager:info("rejecting ~p: ~p",
- [x509:cert_string(LeafCert), Reason]),
- html("add-chain: invalid chain", Reason)
- end;
- Invalid ->
- html("add-chain: chain is not a list: ", [Invalid])
- end;
- _ -> html("add-chain: missing input: chain", Input)
- end;
+ add_chain(Input, normal);
-request(post, "ct/v1/add-pre-chain", _Input) ->
- niy();
+request(post, "ct/v1/add-pre-chain", Input) ->
+ add_chain(Input, precert);
request(get, "ct/v1/get-sth", _Query) ->
R = plop:sth(),
@@ -130,8 +106,33 @@ html(Text, Input) ->
"~p~n" ++
"</body></html>~n", [Text, Input])}.
-niy() ->
- html("NIY - Not Implemented Yet|", []).
-
success(Data) ->
{200, [{"Content-Type", "text/json"}], mochijson2:encode(Data)}.
+
+-spec add_chain(any(), normal|precert) -> any().
+add_chain(Input, Type) ->
+ case (catch mochijson2:decode(Input)) of
+ {error, E} ->
+ html("add-chain: bad input:", E);
+ {struct, [{<<"chain">>, ChainBase64}]} ->
+ case (catch [base64:decode(X) || X <- ChainBase64]) of
+ {'EXIT', _} ->
+ html("add-chain: invalid base64-encoded chain: ",
+ [ChainBase64]);
+ [LeafCert | CertChain] ->
+ case x509:valid_chain_p(catlfish:known_roots(),
+ [LeafCert|CertChain]) of
+ {ok, [Leaf | Chain]} ->
+ lager:info("adding ~p cert ~p",
+ [Type, x509:cert_string(LeafCert)]),
+ success(catlfish:add_chain(Leaf, Chain, Type));
+ {error, Reason} ->
+ lager:info("rejecting ~p: ~p",
+ [x509:cert_string(LeafCert), Reason]),
+ html("add-chain: invalid chain", Reason)
+ end;
+ Invalid ->
+ html("add-chain: chain is not a list: ", [Invalid])
+ end;
+ _ -> html("add-chain: missing input: chain", Input)
+ end.
diff --git a/src/x509.erl b/src/x509.erl
index 5a0e871..278686b 100644
--- a/src/x509.erl
+++ b/src/x509.erl
@@ -2,11 +2,11 @@
%%% See LICENSE for licensing information.
-module(x509).
--export([normalise_chain/2, cert_string/1, read_pemfiles_from_dir/1,
- self_signed/1]).
-
+-export([valid_chain_p/2, cert_string/1, read_pemfiles_from_dir/1,
+ self_signed/1, detox/2]).
-include_lib("public_key/include/public_key.hrl").
-include_lib("eunit/include/eunit.hrl").
+-import(lists, [nth/2, filter/2]).
-type reason() :: {chain_too_long |
root_unknown |
@@ -15,18 +15,52 @@
-define(MAX_CHAIN_LENGTH, 10).
--spec normalise_chain([binary()], [binary()]) -> {ok, [binary()]} |
- {error, reason()}.
-normalise_chain(AcceptableRootCerts, CertChain) ->
+-spec valid_chain_p([binary()], [binary()]) -> {ok, [binary()]} |
+ {error, reason()}.
+valid_chain_p(AcceptableRootCerts, CertChain) ->
case valid_chain_p(AcceptableRootCerts, CertChain, ?MAX_CHAIN_LENGTH) of
{false, Reason} ->
{error, Reason};
{true, Root} ->
- [Leaf | Chain] = CertChain,
- {ok, [detox_precert(Leaf) | Chain] ++ Root}
+ {ok, CertChain ++ Root}
end.
-%%%%%%%%%%%%%%%%%%%%
+cert_string(Der) ->
+ mochihex:to_hex(crypto:hash(sha, Der)).
+
+-spec read_pemfiles_from_dir(file:filename()) -> [binary()].
+%% @doc Reading certificates from files. Flattening the result -- all
+%% certs in all files are returned in a single list.
+read_pemfiles_from_dir(Dir) ->
+ case file:list_dir(Dir) of
+ {error, enoent} ->
+ lager:error("directory does not exist: ~p", [Dir]),
+ [];
+ {error, Reason} ->
+ lager:error("unable to read directory ~p: ~p", [Dir, Reason]),
+ [];
+ {ok, Filenames} ->
+ Files = lists:filter(
+ fun(F) ->
+ string:equal(".pem", filename:extension(F))
+ end,
+ Filenames),
+ ders_from_pemfiles(Dir, Files)
+ end.
+
+-spec self_signed([binary()]) -> [binary()].
+%% @doc Return a list of certs in L that are self signed.
+self_signed(L) ->
+ lists:filter(fun(Cert) -> signed_by_p(Cert, Cert) end, L).
+
+%% @doc Return the detoxed cet in LeafDer and the issuer leaf hash.
+-spec detox(binary(), [binary()]) -> {binary(), binary()}.
+detox(LeafDer, ChainDer) ->
+ detox_precert(LeafDer, nth(1, ChainDer), nth(2, ChainDer)).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Private functions.
+
%% @doc Verify that the leaf cert or precert has a valid chain back to
%% an acceptable root cert. The order of certificates in the second
%% argument is: leaf cert in head, chain in tail. Order of first
@@ -90,9 +124,10 @@ encoded_tbs_cert(DerCert) ->
PKIXCert,
EncodedTBSCert.
+-spec extract_verify_data(#'Certificate'{}, binary()) -> {ok, tuple()} | error.
+%% @doc Return DER encoded TBScertificate, digest type and signature.
%% Code from pubkey_cert:extract_verify_data/2.
--spec verifydata_from_cert(#'Certificate'{}, binary()) -> {ok, tuple()} | error.
-verifydata_from_cert(Cert, DerCert) ->
+extract_verify_data(Cert, DerCert) ->
PlainText = encoded_tbs_cert(DerCert),
{_, Sig} = Cert#'Certificate'.signature,
SigAlgRecord = Cert#'Certificate'.signatureAlgorithm,
@@ -114,7 +149,7 @@ verify_sig(Cert, DerCert, % Certificate to verify.
tbsCertificate = #'TBSCertificate'{
subjectPublicKeyInfo = IssuerSPKI}}) ->
%% Dig out digest, digest type and signature from Cert/DerCert.
- case verifydata_from_cert(Cert, DerCert) of
+ case extract_verify_data(Cert, DerCert) of
error -> false;
{ok, Tuple} -> verify_sig2(IssuerSPKI, Tuple)
end.
@@ -159,9 +194,6 @@ signed_by_p(DerCert, IssuerDerCert) when is_binary(DerCert),
DerCert,
public_key:pkix_decode_cert(IssuerDerCert, plain)).
-cert_string(Der) ->
- mochihex:to_hex(crypto:hash(sha, Der)).
-
parsable_cert_p(Der) ->
case (catch public_key:pkix_decode_cert(Der, plain)) of
#'Certificate'{} ->
@@ -175,54 +207,91 @@ parsable_cert_p(Der) ->
false
end.
--spec self_signed([binary()]) -> [binary()].
-self_signed(L) ->
- lists:filter(fun(Cert) -> signed_by_p(Cert, Cert) end, L).
-
-%%%%%%%%%%%%%%%%%%%%
-%% Precertificates according to draft-ietf-trans-rfc6962-bis-04.
+%% Precerts according to RFC6962.
%% Submitted precerts have a special critical poison extension -- OID
%% 1.3.6.1.4.1.11129.2.4.3, whose extnValue OCTET STRING contains
%% ASN.1 NULL data (0x05 0x00).
%% They are signed with either the CA cert that will sign the final
-%% cert or Precertificate Signing Certificate directly signed by the
+%% cert or a Precertificate Signing Certificate directly signed by the
%% CA cert that will sign the final cert. A Precertificate Signing
%% Certificate has CA:true and Extended Key Usage: Certificate
%% Transparency, OID 1.3.6.1.4.1.11129.2.4.4.
-%% A PreCert in a SignedCertificateTimestamp does _not_ contain the
-%% poison extension, nor a Precertificate Signing Certificate. This
-%% means that we might have to 1) remove poison extensions in leaf
-%% certs, 2) remove "poisoned signatures", 3) change issuer and
-%% Authority Key Identifier of leaf certs.
-
--spec detox_precert([#'Certificate'{}]) -> [#'Certificate'{}].
-detox_precert(CertChain) ->
- CertChain. % NYI
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
--spec read_pemfiles_from_dir(file:filename()) -> [binary()].
-%% @doc Reading certificates from files. Flattening the result -- all
-%% certs in all files are returned in a single list.
-read_pemfiles_from_dir(Dir) ->
- case file:list_dir(Dir) of
- {error, enoent} ->
- lager:error("directory does not exist: ~p", [Dir]),
- [];
- {error, Reason} ->
- lager:error("unable to read directory ~p: ~p", [Dir, Reason]),
- [];
- {ok, Filenames} ->
- Files = lists:filter(
- fun(F) ->
- string:equal(".pem", filename:extension(F))
- end,
- Filenames),
- ders_from_pemfiles(Dir, Files)
- end.
-
+%% PreCert in SignedCertificateTimestamp does _not_ contain the poison
+%% extension, nor does it have an issuer which is a Precertificate
+%% Signing Certificate. This means that we have to 1) remove the
+%% poison extension and 2) potentially change issuer and Authority Key
+%% Identifier. See RFC6962 Section 3.2.
+
+%% Changes in draft-ietf-trans-rfc6962-bis-??: TODO.
+
+-spec detox_precert(binary(), binary(), binary()) -> {binary(), binary()}.
+detox_precert(LeafDer, ParentDer, GrandParentDer) ->
+ Leaf = public_key:pkix_decode_cert(LeafDer, plain),
+ Parent = public_key:pkix_decode_cert(ParentDer, plain),
+ GrandParent = public_key:pkix_decode_cert(GrandParentDer, plain),
+
+ DetoxedLeafTBS = remove_poison_ext(Leaf),
+
+ %% If parent is a precert signing cert, change issuer and
+ %% authority key id to refer to grandparent.
+ {C, IssuerKeyHash} =
+ case is_precert_signer(Parent) of
+ true ->
+ GrandParent = public_key:pkix_decode_cert(GrandParentDer, plain),
+ {change_issuer(DetoxedLeafTBS, GrandParent),
+ extract_pub_key(GrandParent)};
+ false ->
+ {DetoxedLeafTBS, extract_pub_key(Parent)}
+ end,
+ {public_key:pkix_encode('TBSCertificate', C, plain),
+ crypto:hash(sha256, public_key:pkix_encode(
+ 'SubjectPublicKeyInfo', IssuerKeyHash, plain))}.
+
+-spec extract_pub_key(#'Certificate'{}) -> #'SubjectPublicKeyInfo'{}.
+extract_pub_key(#'Certificate'{
+ tbsCertificate = #'TBSCertificate'{
+ subjectPublicKeyInfo = SPKI}}) ->
+ SPKI.
+
+change_issuer(Cert, _) ->
+ %% FIXME: NIY.
+ Cert.
+
+-spec is_precert_signer(#'Certificate'{}) -> boolean().
+is_precert_signer(Cert) ->
+ %%ca_cert_p(Cert) and has_critext(Cert, {1,3,6,1,4,1,11129,2,4,4}.
+ ca_cert_p(Cert), false. % FIXME: NIY
+
+-spec ca_cert_p(#'Certificate'{}) -> boolean().
+ca_cert_p(Cert) ->
+ %% TBS = Cert#'Certificate'.tbsCertificate,
+ %% {ExtnID, Critical, ExtnValue} = TBS#'TBSCertificate'.extensions,
+ Cert. % FIXME: NIY
+
+-define(LEAF_POISON_OID, {1,3,6,1,4,1,11129,2,4,3}).
+-define(LEAF_POISON_VAL, asn1_NOVALUE).
+
+-spec remove_poison_ext(#'Certificate'{}) -> #'TBSCertificate'{}.
+remove_poison_ext(Cert) ->
+ TBSCert = Cert#'Certificate'.tbsCertificate,
+ Extensions = pubkey_cert:extensions_list(TBSCert#'TBSCertificate'.extensions),
+ SanitisedExtensions =
+ filter(fun(E) -> not poisoned_leaf_p(E) end, Extensions),
+ NewTBSCert = TBSCert#'TBSCertificate'{extensions = SanitisedExtensions},
+ %%Cert#'Certificate'{tbsCertificate = NewTBSCert}.
+ NewTBSCert.
+
+poisoned_leaf_p(#'Extension'{extnID = ?LEAF_POISON_OID,
+ critical = true,
+ extnValue = ?LEAF_POISON_VAL}) ->
+ true;
+poisoned_leaf_p(_) ->
+ false.
+
+%%%% PEM files.
ders_from_pemfiles(Dir, Filenames) ->
lists:flatten(
[ders_from_pemfile(filename:join(Dir, X)) || X <- Filenames]).