Merge pull request #6889 from SparkiDev/sm2_priv_import_range

JacobBarthelmeh · web-flow · commit 1abaa941205d · 2023-10-19T17:12:07.000-06:00
ECC SM2 import private key: check less than order-1
diff --git a/wolfcrypt/src/ecc.c b/wolfcrypt/src/ecc.c
@@ -10883,6 +10883,13 @@ int wc_ecc_import_private_key_ex(const byte* priv, word32 privSz,
         if (ret == 0) {
             ret = mp_read_radix(order, key->dp->order, MP_RADIX_HEX);
         }
+    #ifdef WOLFSSL_SM2
+        /* SM2 curve: private key must be less than order-1. */
+        if ((ret == 0) && (key->idx != ECC_CUSTOM_IDX) &&
+                (ecc_sets[key->idx].id == ECC_SM2P256V1)) {
+            ret = mp_sub_d(order, 1, order);
+        }
+    #endif
         if ((ret == 0) && (mp_cmp(key->k, order) != MP_LT)) {
             ret = ECC_PRIV_KEY_E;
         }

Original file line number	Diff line number	Diff line change
`@@ -10883,6 +10883,13 @@ int wc_ecc_import_private_key_ex(const byte* priv, word32 privSz,`
`10883`	`10883`	`if (ret == 0) {`
`10884`	`10884`	`ret = mp_read_radix(order, key->dp->order, MP_RADIX_HEX);`
`10885`	`10885`	`}`
	`10886`	`+ #ifdef WOLFSSL_SM2`
	`10887`	`+ /* SM2 curve: private key must be less than order-1. */`
	`10888`	`+ if ((ret == 0) && (key->idx != ECC_CUSTOM_IDX) &&`
	`10889`	`+ (ecc_sets[key->idx].id == ECC_SM2P256V1)) {`
	`10890`	`+ ret = mp_sub_d(order, 1, order);`
	`10891`	`+ }`
	`10892`	`+ #endif`
`10886`	`10893`	`if ((ret == 0) && (mp_cmp(key->k, order) != MP_LT)) {`
`10887`	`10894`	`ret = ECC_PRIV_KEY_E;`
`10888`	`10895`	`}`