diff options
Diffstat (limited to 'lib/ssl/src/tls_handshake.erl')
| -rw-r--r-- | lib/ssl/src/tls_handshake.erl | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/ssl/src/tls_handshake.erl b/lib/ssl/src/tls_handshake.erl index 39f0c1680b..7004c7a2f4 100644 --- a/lib/ssl/src/tls_handshake.erl +++ b/lib/ssl/src/tls_handshake.erl @@ -106,6 +106,34 @@ client_hello(Host, Port, ConnectionStates, %% Description: Handles a received hello message %%-------------------------------------------------------------------- + +%% TLS 1.3 - Section 4.1.3 +%% TLS 1.3 clients receiving a ServerHello indicating TLS 1.2 or below +%% MUST check that the last eight bytes are not equal to either of these +%% values. +hello(#server_hello{server_version = {Major, Minor}, + random = <<_:24/binary,Down:8/binary>>}, + #ssl_options{versions = [{M,N}|_]}, _, _) + when (M > 3 orelse M =:= 3 andalso N >= 4) andalso %% TLS 1.3 client + (Major =:= 3 andalso Minor =:= 3 andalso %% Negotiating TLS 1.2 + Down =:= ?RANDOM_OVERRIDE_TLS12) orelse + + (M > 3 orelse M =:= 3 andalso N >= 4) andalso %% TLS 1.3 client + (Major =:= 3 andalso Minor < 3 andalso %% Negotiating TLS 1.1 or prior + Down =:= ?RANDOM_OVERRIDE_TLS11) -> + ?ALERT_REC(?FATAL, ?ILLEGAL_PARAMETER); + +%% TLS 1.2 clients SHOULD also check that the last eight bytes are not +%% equal to the second value if the ServerHello indicates TLS 1.1 or below. +hello(#server_hello{server_version = {Major, Minor}, + random = <<_:24/binary,Down:8/binary>>}, + #ssl_options{versions = [{M,N}|_]}, _, _) + when (M =:= 3 andalso N =:= 3) andalso %% TLS 1.2 client + (Major =:= 3 andalso Minor < 3 andalso %% Negotiating TLS 1.1 or prior + Down =:= ?RANDOM_OVERRIDE_TLS11) -> + ?ALERT_REC(?FATAL, ?ILLEGAL_PARAMETER); + + %% TLS 1.3 - 4.2.1. Supported Versions %% If the "supported_versions" extension in the ServerHello contains a %% version not offered by the client or contains a version prior to TLS |