Support additional curve names.

Node's default settings spell P-256 as prime256v1. This comes from
OpenSSL additionally allowing the long and short names of each curve's
NID. This works out to one additional name per curve for the ones we
support. To avoid depending on the giant OID table, this replicates the
names in libssl.

Change-Id: I456a2db6939eb6745e5a9d2f12cf6886e6265b9f
Reviewed-on: https://boringssl-review.googlesource.com/22545
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

ssl/ssl_key_share.cc

@@ -171,13 +171,13 @@ class X25519KeyShare : public SSLKeyShare {
 CONSTEXPR_ARRAY struct {
   int nid;
   uint16_t group_id;
-  const char name[8];
+  const char name[8], alias[11];
 } kNamedGroups[] = {
-    {NID_secp224r1, SSL_CURVE_SECP224R1, "P-224"},
-    {NID_X9_62_prime256v1, SSL_CURVE_SECP256R1, "P-256"},
-    {NID_secp384r1, SSL_CURVE_SECP384R1, "P-384"},
-    {NID_secp521r1, SSL_CURVE_SECP521R1, "P-521"},
-    {NID_X25519, SSL_CURVE_X25519, "X25519"},
+    {NID_secp224r1, SSL_CURVE_SECP224R1, "P-224", "secp224r1"},
+    {NID_X9_62_prime256v1, SSL_CURVE_SECP256R1, "P-256", "prime256v1"},
+    {NID_secp384r1, SSL_CURVE_SECP384R1, "P-384", "secp384r1"},
+    {NID_secp521r1, SSL_CURVE_SECP521R1, "P-521", "secp521r1"},
+    {NID_X25519, SSL_CURVE_X25519, "X25519", "x25519"},
 };
 
 }  // namespace
@@ -227,6 +227,11 @@ int ssl_name_to_group_id(uint16_t *out_group_id, const char *name, size_t len) {
       *out_group_id = group.group_id;
       return 1;
     }
+    if (len == strlen(group.alias) &&
+        !strncmp(group.alias, name, len)) {
+      *out_group_id = group.group_id;
+      return 1;
+    }
   }
   return 0;
 }

ssl/ssl_test.cc

@@ -379,6 +379,15 @@ static const CurveTest kCurveTests[] = {
       SSL_CURVE_X25519,
     },
   },
+  {
+    "prime256v1:secp384r1:secp521r1:x25519",
+    {
+      SSL_CURVE_SECP256R1,
+      SSL_CURVE_SECP384R1,
+      SSL_CURVE_SECP521R1,
+      SSL_CURVE_X25519,
+    },
+  },
 };
 
 static const char *kBadCurvesLists[] = {