SAE: Use EC group context for peer-commit-scalar validation

Do not use the hardcoded group19_order/group19_prime buffers for this to
allow group negotiation.

Signed-hostap: Jouni Malinen <j@w1.fi>

diff --git a/src/common/sae.c b/src/common/sae.c
index de4709da253d9e0f158b044e657269b625e33a4d..efa85f067207b388226ec8bb812681e169ae5798 100644 (file)
--- a/src/common/sae.c
+++ b/src/common/sae.c
@@ -23,13 +23,6 @@ static const u8 group19_prime[] = {
        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
 };
 
-static const u8 group19_order[] = {
-       0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00,
-       0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
-       0xBC, 0xE6, 0xFA, 0xAD, 0xA7, 0x17, 0x9E, 0x84,
-       0xF3, 0xB9, 0xCA, 0xC2, 0xFC, 0x63, 0x25, 0x51
-};
-
 
 int sae_set_group(struct sae_data *sae, int group)
 {
@@ -315,10 +308,15 @@ int sae_prepare_commit(const u8 *addr1, const u8 *addr2,
 
 static int sae_check_peer_commit(struct sae_data *sae)
 {
+       u8 order[SAE_MAX_PRIME_LEN];
+
+       if (crypto_bignum_to_bin(crypto_ec_get_order(sae->ec),
+                                order, sizeof(order), sae->prime_len) < 0)
+               return -1;
+
        /* 0 < scalar < r */
        if (val_zero(sae->peer_commit_scalar, sae->prime_len) ||
-           os_memcmp(sae->peer_commit_scalar, group19_order,
-                     sizeof(group19_prime)) >= 0) {
+           os_memcmp(sae->peer_commit_scalar, order, sae->prime_len) >= 0) {
                wpa_printf(MSG_DEBUG, "SAE: Invalid peer scalar");
                return -1;
        }