diff options
Diffstat (limited to 'lib/ssl/src/tls_v1.erl')
| -rw-r--r-- | lib/ssl/src/tls_v1.erl | 42 |
1 files changed, 34 insertions, 8 deletions
diff --git a/lib/ssl/src/tls_v1.erl b/lib/ssl/src/tls_v1.erl index df2a421bce..5c023bd2d8 100644 --- a/lib/ssl/src/tls_v1.erl +++ b/lib/ssl/src/tls_v1.erl @@ -37,14 +37,14 @@ groups/1, groups/2, group_to_enum/1, enum_to_group/1, default_groups/1]). -export([derive_secret/4, hkdf_expand_label/5, hkdf_extract/3, hkdf_expand/4, - key_schedule/3, key_schedule/4, + key_schedule/3, key_schedule/4, create_info/3, external_binder_key/2, resumption_binder_key/2, client_early_traffic_secret/3, early_exporter_master_secret/3, client_handshake_traffic_secret/3, server_handshake_traffic_secret/3, client_application_traffic_secret_0/3, server_application_traffic_secret_0/3, exporter_master_secret/3, resumption_master_secret/3, update_traffic_secret/2, calculate_traffic_keys/3, - transcript_hash/2]). + transcript_hash/2, finished_key/2, finished_verify_data/3]). -type named_curve() :: sect571r1 | sect571k1 | secp521r1 | brainpoolP512r1 | sect409k1 | sect409r1 | brainpoolP384r1 | secp384r1 | @@ -74,18 +74,24 @@ derive_secret(Secret, Label, Messages, Algo) -> Context::binary(), Length::integer(), Algo::ssl_cipher_format:hash()) -> KeyingMaterial::binary(). hkdf_expand_label(Secret, Label0, Context, Length, Algo) -> + HkdfLabel = create_info(Label0, Context, Length), + hkdf_expand(Secret, HkdfLabel, Length, Algo). + +%% Create info parameter for HKDF-Expand: +%% HKDF-Expand(PRK, info, L) -> OKM +create_info(Label0, Context0, Length) -> %% struct { %% uint16 length = Length; %% opaque label<7..255> = "tls13 " + Label; %% opaque context<0..255> = Context; %% } HkdfLabel; Label1 = << <<"tls13 ">>/binary, Label0/binary>>, - LLen = size(Label1), - Label = <<?BYTE(LLen), Label1/binary>>, + LabelLen = size(Label1), + Label = <<?BYTE(LabelLen), Label1/binary>>, + ContextLen = size(Context0), + Context = <<?BYTE(ContextLen),Context0/binary>>, Content = <<Label/binary, Context/binary>>, - Len = size(Content), - HkdfLabel = <<?UINT16(Len), Content/binary>>, - hkdf_expand(Secret, HkdfLabel, Length, Algo). + <<?UINT16(Length), Content/binary>>. -spec hkdf_extract(MacAlg::ssl_cipher_format:hash(), Salt::binary(), KeyingMaterial::binary()) -> PseudoRandKey::binary(). @@ -368,6 +374,25 @@ exporter_master_secret(Algo, {master_secret, Secret}, M) -> resumption_master_secret(Algo, {master_secret, Secret}, M) -> derive_secret(Secret, <<"res master">>, M, Algo). +-spec finished_key(binary(), atom()) -> binary(). +finished_key(BaseKey, Algo) -> + %% finished_key = + %% HKDF-Expand-Label(BaseKey, "finished", "", Hash.length) + ssl_cipher:hash_size(Algo), + hkdf_expand_label(BaseKey, <<"finished">>, <<>>, ssl_cipher:hash_size(Algo), Algo). + +-spec finished_verify_data(binary(), atom(), iodata()) -> binary(). +finished_verify_data(FinishedKey, HKDFAlgo, Messages) -> + %% The verify_data value is computed as follows: + %% + %% verify_data = + %% HMAC(finished_key, + %% Transcript-Hash(Handshake Context, + %% Certificate*, CertificateVerify*)) + Context = lists:reverse(Messages), + THash = tls_v1:transcript_hash(Context, HKDFAlgo), + tls_v1:hmac_hash(HKDFAlgo, FinishedKey, THash). + %% The next-generation application_traffic_secret is computed as: %% %% application_traffic_secret_N+1 = @@ -394,7 +419,8 @@ update_traffic_secret(Algo, Secret) -> -spec calculate_traffic_keys(atom(), atom(), binary()) -> {binary(), binary()}. calculate_traffic_keys(HKDFAlgo, Cipher, Secret) -> Key = hkdf_expand_label(Secret, <<"key">>, <<>>, ssl_cipher:key_material(Cipher), HKDFAlgo), - IV = hkdf_expand_label(Secret, <<"iv">>, <<>>, ssl_cipher:key_material(Cipher), HKDFAlgo), + %% TODO: remove hard coded IV size + IV = hkdf_expand_label(Secret, <<"iv">>, <<>>, 12, HKDFAlgo), {Key, IV}. %% TLS v1.3 --------------------------------------------------- |