Tests: $ssl_curve.
diff --git a/ssl_curve.t b/ssl_curve.t
new file mode 100644
index 0000000..3b6d27d
--- /dev/null
+++ b/ssl_curve.t
@@ -0,0 +1,124 @@
+#!/usr/bin/perl
+
+# (C) Sergey Kandaurov
+# (C) Nginx, Inc.
+
+# Tests for http ssl module, $ssl_curve variable.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+eval { require IO::Socket::SSL; };
+plan(skip_all => 'IO::Socket::SSL not installed') if $@;
+eval { IO::Socket::SSL::SSL_VERIFY_NONE(); };
+plan(skip_all => 'IO::Socket::SSL too old') if $@;
+
+my $t = Test::Nginx->new()->has(qw/http http_ssl rewrite/)
+ ->has_daemon('openssl');
+
+$t->{_configure_args} =~ /OpenSSL (\d+)/;
+plan(skip_all => 'OpenSSL too old') unless defined $1 and $1 >= 3;
+
+$t->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+ %%TEST_GLOBALS_HTTP%%
+
+ ssl_certificate_key localhost.key;
+ ssl_certificate localhost.crt;
+
+ ssl_ecdh_curve prime256v1;
+
+ server {
+ listen 127.0.0.1:8443 ssl;
+ server_name localhost;
+
+ return 200 "$ssl_curve $ssl_curves";
+ }
+}
+
+EOF
+
+$t->write_file('openssl.conf', <<EOF);
+[ req ]
+default_bits = 2048
+encrypt_key = no
+distinguished_name = req_distinguished_name
+[ req_distinguished_name ]
+EOF
+
+my $d = $t->testdir();
+
+foreach my $name ('localhost') {
+ system('openssl req -x509 -new '
+ . "-config $d/openssl.conf -subj /CN=$name/ "
+ . "-out $d/$name.crt -keyout $d/$name.key "
+ . ">>$d/openssl.out 2>&1") == 0
+ or die "Can't create certificate for $name: $!\n";
+}
+
+$t->try_run('no $ssl_curve')->plan(1);
+
+###############################################################################
+
+like(get('/curve'), qr/^prime256v1 /m, 'ssl curve');
+
+###############################################################################
+
+sub get {
+ my ($uri, $port, $ctx) = @_;
+ my $s = get_ssl_socket($port) or return;
+ my $r = http_get($uri, socket => $s);
+ $s->close();
+ return $r;
+}
+
+sub get_ssl_socket {
+ my ($port, $ctx) = @_;
+ my $s;
+
+ eval {
+ local $SIG{ALRM} = sub { die "timeout\n" };
+ local $SIG{PIPE} = sub { die "sigpipe\n" };
+ alarm(8);
+ $s = IO::Socket::SSL->new(
+ Proto => 'tcp',
+ PeerAddr => '127.0.0.1',
+ PeerPort => port(8443),
+ SSL_verify_mode => IO::Socket::SSL::SSL_VERIFY_NONE(),
+ SSL_error_trap => sub { die $_[1] },
+ );
+ alarm(0);
+ };
+ alarm(0);
+
+ if ($@) {
+ log_in("died: $@");
+ return undef;
+ }
+
+ return $s;
+}
+
+###############################################################################