Prune away unimplemented curve IDs.
We only implement four curves (P-224, P-256, P-384, and P-521) and only
advertise the latter three by default. Don't maintain entries corresponding to
all the unimplemented curves.
Change-Id: I1816a10c6f849ca1d9d896bc6f4b64cd6b329481
Reviewed-on: https://boringssl-review.googlesource.com/2843
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index d2660d0..224d636 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -349,36 +349,26 @@
return 0;
}
-/* ECC curves from RFC4492 */
-static const int nid_list[] = {
- NID_sect163k1, /* sect163k1 (1) */
- NID_sect163r1, /* sect163r1 (2) */
- NID_sect163r2, /* sect163r2 (3) */
- NID_sect193r1, /* sect193r1 (4) */
- NID_sect193r2, /* sect193r2 (5) */
- NID_sect233k1, /* sect233k1 (6) */
- NID_sect233r1, /* sect233r1 (7) */
- NID_sect239k1, /* sect239k1 (8) */
- NID_sect283k1, /* sect283k1 (9) */
- NID_sect283r1, /* sect283r1 (10) */
- NID_sect409k1, /* sect409k1 (11) */
- NID_sect409r1, /* sect409r1 (12) */
- NID_sect571k1, /* sect571k1 (13) */
- NID_sect571r1, /* sect571r1 (14) */
- NID_secp160k1, /* secp160k1 (15) */
- NID_secp160r1, /* secp160r1 (16) */
- NID_secp160r2, /* secp160r2 (17) */
- NID_secp192k1, /* secp192k1 (18) */
- NID_X9_62_prime192v1, /* secp192r1 (19) */
- NID_secp224k1, /* secp224k1 (20) */
- NID_secp224r1, /* secp224r1 (21) */
- NID_secp256k1, /* secp256k1 (22) */
- NID_X9_62_prime256v1, /* secp256r1 (23) */
- NID_secp384r1, /* secp384r1 (24) */
- NID_secp521r1, /* secp521r1 (25) */
- NID_brainpoolP256r1, /* brainpoolP256r1 (26) */
- NID_brainpoolP384r1, /* brainpoolP384r1 (27) */
- NID_brainpoolP512r1 /* brainpool512r1 (28) */
+struct tls_curve {
+ uint16_t curve_id;
+ int nid;
+};
+
+/* ECC curves from RFC4492.
+ *
+ * NOTE: tls1_ec_curve_id2nid and tls1_set_curves assume that
+ *
+ * (a) 0 is not a valid curve ID.
+ *
+ * (b) The largest curve ID is 31.
+ *
+ * Those implementations must be revised before adding support for curve IDs
+ * that break these assumptions. */
+static const struct tls_curve tls_curves[] = {
+ {21, NID_secp224r1},
+ {23, NID_X9_62_prime256v1},
+ {24, NID_secp384r1},
+ {25, NID_secp521r1},
};
static const uint8_t ecformats_default[] = {
@@ -386,29 +376,31 @@
};
static const uint16_t eccurves_default[] = {
- 23, /* secp256r1 (23) */
- 24, /* secp384r1 (24) */
- 25, /* secp521r1 (25) */
+ 23, /* X9_64_prime256v1 */
+ 24, /* secp384r1 */
+ 25, /* secp521r1 */
};
int tls1_ec_curve_id2nid(uint16_t curve_id) {
- if (curve_id < 1 || curve_id > sizeof(nid_list) / sizeof(nid_list[0])) {
- return NID_undef;
+ size_t i;
+ for (i = 0; i < sizeof(tls_curves) / sizeof(tls_curves[0]); i++) {
+ if (curve_id == tls_curves[i].curve_id) {
+ return tls_curves[i].nid;
+ }
}
- return nid_list[curve_id - 1];
+ return NID_undef;
}
uint16_t tls1_ec_nid2curve_id(int nid) {
size_t i;
- for (i = 0; i < sizeof(nid_list) / sizeof(nid_list[0]); i++) {
- /* nid_list[i] stores the NID corresponding to curve ID i+1. */
- if (nid == nid_list[i]) {
- return i + 1;
+ for (i = 0; i < sizeof(tls_curves) / sizeof(tls_curves[0]); i++) {
+ if (nid == tls_curves[i].nid) {
+ return tls_curves[i].curve_id;
}
}
- /* Use 0 for non-existent curve ID. Note: this assumes that curve ID 0 will
- * never be allocated. */
+ /* Use 0 for a non-existent curve ID. Note: this assumes that curve
+ * ID 0 will never be allocated. */
return 0;
}
@@ -482,17 +474,6 @@
return NID_undef;
}
-/* NOTE: tls1_ec_curve_id2nid and tls1_set_curves assume that
- *
- * (a) 0 is not a valid curve ID.
- *
- * (b) The largest curve ID is 31.
- *
- * Those implementations must be revised before adding support for curve IDs
- * that break these assumptions. */
-OPENSSL_COMPILE_ASSERT((sizeof(nid_list) / sizeof(nid_list[0])) < 32,
- small_curve_ids);
-
int tls1_set_curves(uint16_t **out_curve_ids, size_t *out_curve_ids_len,
const int *curves, size_t ncurves) {
uint16_t *curve_ids;
