From b203ff6e20bc80363ebfc7204e7fdd1ae656e046 Mon Sep 17 00:00:00 2001
From: Jerome Magnin <jmagnin@haproxy.com>
Date: Fri, 3 Apr 2020 15:28:22 +0200
Subject: [PATCH] MINOR: config: add a global directive to set default SSL
 curves

This commit adds a new keyword to the global section to set default
curves for ssl binds:
  - ssl-default-bind-curves
---
 doc/configuration.txt |  8 ++++++++
 src/ssl_sock.c        | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+)

diff --git a/doc/configuration.txt b/doc/configuration.txt
index a6ff8df34..f3e6aa147 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -622,6 +622,7 @@ The following keywords are supported in the "global" section :
    - stats
    - ssl-default-bind-ciphers
    - ssl-default-bind-ciphersuites
+   - ssl-default-bind-curves
    - ssl-default-bind-options
    - ssl-default-server-ciphers
    - ssl-default-server-ciphersuites
@@ -1271,6 +1272,13 @@ ssl-default-bind-ciphersuites <ciphersuites>
   "ssl-default-bind-ciphers" keyword. Please check the "bind" keyword for more
   information.
 
+ssl-default-bind-curves <curves>
+  This setting is only available when support for OpenSSL was built in. It sets
+  the default string describing the list of elliptic curves algorithms ("curve
+  suite") that are negotiated during the SSL/TLS handshake with ECDHE. The format
+  of the string is a colon-delimited list of curve name.
+  Please check the "bind" keyword for more information.
+
 ssl-default-bind-options [<option>]...
   This setting is only available when support for OpenSSL was built in. It sets
   default ssl-options to force on all "bind" lines. Please check the "bind"
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 437478819..12b40123d 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -176,6 +176,9 @@ static struct {
 #if (HA_OPENSSL_VERSION_NUMBER >= 0x10101000L)
 	char *listen_default_ciphersuites;
 	char *connect_default_ciphersuites;
+#endif
+#if ((HA_OPENSSL_VERSION_NUMBER >= 0x1000200fL) || defined(LIBRESSL_VERSION_NUMBER))
+	char *listen_default_curves;
 #endif
 	int listen_default_ssloptions;
 	int connect_default_ssloptions;
@@ -9517,6 +9520,10 @@ static int bind_parse_ssl(char **args, int cur_arg, struct proxy *px, struct bin
 
 	if (global_ssl.listen_default_ciphers && !conf->ssl_conf.ciphers)
 		conf->ssl_conf.ciphers = strdup(global_ssl.listen_default_ciphers);
+#if ((HA_OPENSSL_VERSION_NUMBER >= 0x1000200fL) || defined(LIBRESSL_VERSION_NUMBER))
+	if (global_ssl.listen_default_curves && !conf->ssl_conf.curves)
+		conf->ssl_conf.curves = strdup(global_ssl.listen_default_curves);
+#endif
 #if (HA_OPENSSL_VERSION_NUMBER >= 0x10101000L)
 	if (global_ssl.listen_default_ciphersuites && !conf->ssl_conf.ciphersuites)
 		conf->ssl_conf.ciphersuites = strdup(global_ssl.listen_default_ciphersuites);
@@ -10513,6 +10520,31 @@ static int ssl_parse_global_ciphersuites(char **args, int section_type, struct p
 }
 #endif
 
+#if ((HA_OPENSSL_VERSION_NUMBER >= 0x1000200fL) || defined(LIBRESSL_VERSION_NUMBER))
+/*
+ * parse the "ssl-default-bind-curves" keyword in a global section.
+ * Returns <0 on alert, >0 on warning, 0 on success.
+ */
+static int ssl_parse_global_curves(char **args, int section_type, struct proxy *curpx,
+                                   struct proxy *defpx, const char *file, int line,
+				   char **err)
+{
+	char **target;
+	target = &global_ssl.listen_default_curves;
+
+	if (too_many_args(1, args, err, NULL))
+		return -1;
+
+	if (*(args[1]) == 0) {
+		memprintf(err, "global statement '%s' expects a curves suite as an arguments.", args[0]);
+		return -1;
+	}
+
+	free(*target);
+	*target = strdup(args[1]);
+	return 0;
+}
+#endif
 /* parse various global tune.ssl settings consisting in positive integers.
  * Returns <0 on alert, >0 on warning, 0 on success.
  */
@@ -13029,6 +13061,9 @@ static struct cfg_kw_list cfg_kws = {ILH, {
 	{ CFG_GLOBAL, "tune.ssl.capture-cipherlist-size", ssl_parse_global_capture_cipherlist },
 	{ CFG_GLOBAL, "ssl-default-bind-ciphers", ssl_parse_global_ciphers },
 	{ CFG_GLOBAL, "ssl-default-server-ciphers", ssl_parse_global_ciphers },
+#if ((HA_OPENSSL_VERSION_NUMBER >= 0x1000200fL) || defined(LIBRESSL_VERSION_NUMBER))
+	{ CFG_GLOBAL, "ssl-default-bind-curves", ssl_parse_global_curves },
+#endif
 #if (HA_OPENSSL_VERSION_NUMBER >= 0x10101000L)
 	{ CFG_GLOBAL, "ssl-default-bind-ciphersuites", ssl_parse_global_ciphersuites },
 	{ CFG_GLOBAL, "ssl-default-server-ciphersuites", ssl_parse_global_ciphersuites },