Implement various _clear() functions with secp256k1_memclear()

Author: real-or-random

src/field_10x26_impl.h

@@ -289,17 +289,6 @@ SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe *a) {
     return a->n[0] & 1;
 }
 
-SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe *a) {
-    int i;
-#ifdef VERIFY
-    a->magnitude = 0;
-    a->normalized = 0;
-#endif
-    for (i=0; i<10; i++) {
-        a->n[i] = 0;
-    }
-}
-
 static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b) {
     int i;
 #ifdef VERIFY

src/field_5x52_impl.h

@@ -252,17 +252,6 @@ SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe *a) {
     return a->n[0] & 1;
 }
 
-SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe *a) {
-    int i;
-#ifdef VERIFY
-    a->magnitude = 0;
-    a->normalized = 0;
-#endif
-    for (i=0; i<5; i++) {
-        a->n[i] = 0;
-    }
-}
-
 static int secp256k1_fe_cmp_var(const secp256k1_fe *a, const secp256k1_fe *b) {
     int i;
 #ifdef VERIFY

src/field_impl.h

@@ -36,6 +36,10 @@ SECP256K1_INLINE static int secp256k1_fe_equal_var(const secp256k1_fe *a, const
     return secp256k1_fe_normalizes_to_zero_var(&na);
 }
 
+SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe *a) {
+    secp256k1_memclear(a, sizeof(secp256k1_fe));
+}
+
 static int secp256k1_fe_sqrt(secp256k1_fe *r, const secp256k1_fe *a) {
     /** Given that p is congruent to 3 mod 4, we can compute the square root of
      *  a mod p as the (p+1)/4'th power of a.

src/group_impl.h

@@ -206,16 +206,11 @@ static void secp256k1_ge_set_infinity(secp256k1_ge *r) {
 }
 
 static void secp256k1_gej_clear(secp256k1_gej *r) {
-    r->infinity = 0;
-    secp256k1_fe_clear(&r->x);
-    secp256k1_fe_clear(&r->y);
-    secp256k1_fe_clear(&r->z);
+    secp256k1_memclear(r, sizeof(secp256k1_gej));
 }
 
 static void secp256k1_ge_clear(secp256k1_ge *r) {
-    r->infinity = 0;
-    secp256k1_fe_clear(&r->x);
-    secp256k1_fe_clear(&r->y);
+    secp256k1_memclear(r, sizeof(secp256k1_ge));
 }
 
 static int secp256k1_ge_set_xquad(secp256k1_ge *r, const secp256k1_fe *x) {

src/scalar_4x64_impl.h

@@ -24,13 +24,6 @@
 #define SECP256K1_N_H_2 ((uint64_t)0xFFFFFFFFFFFFFFFFULL)
 #define SECP256K1_N_H_3 ((uint64_t)0x7FFFFFFFFFFFFFFFULL)
 
-SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) {
-    r->d[0] = 0;
-    r->d[1] = 0;
-    r->d[2] = 0;
-    r->d[3] = 0;
-}
-
 SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v) {
     r->d[0] = v;
     r->d[1] = 0;

src/scalar_8x32_impl.h

@@ -34,17 +34,6 @@
 #define SECP256K1_N_H_6 ((uint32_t)0xFFFFFFFFUL)
 #define SECP256K1_N_H_7 ((uint32_t)0x7FFFFFFFUL)
 
-SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) {
-    r->d[0] = 0;
-    r->d[1] = 0;
-    r->d[2] = 0;
-    r->d[3] = 0;
-    r->d[4] = 0;
-    r->d[5] = 0;
-    r->d[6] = 0;
-    r->d[7] = 0;
-}
-
 SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v) {
     r->d[0] = v;
     r->d[1] = 0;

src/scalar_impl.h

@@ -27,6 +27,10 @@
 static const secp256k1_scalar secp256k1_scalar_one = SECP256K1_SCALAR_CONST(0, 0, 0, 0, 0, 0, 0, 1);
 static const secp256k1_scalar secp256k1_scalar_zero = SECP256K1_SCALAR_CONST(0, 0, 0, 0, 0, 0, 0, 0);
 
+SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) {
+    secp256k1_memclear(r, sizeof(secp256k1_scalar));
+}
+
 #ifndef USE_NUM_NONE
 static void secp256k1_scalar_get_num(secp256k1_num *r, const secp256k1_scalar *a) {
     unsigned char c[32];

src/scalar_low_impl.h

@@ -15,7 +15,6 @@ SECP256K1_INLINE static int secp256k1_scalar_is_even(const secp256k1_scalar *a)
     return !(*a & 1);
 }
 
-SECP256K1_INLINE static void secp256k1_scalar_clear(secp256k1_scalar *r) { *r = 0; }
 SECP256K1_INLINE static void secp256k1_scalar_set_int(secp256k1_scalar *r, unsigned int v) { *r = v; }
 
 SECP256K1_INLINE static unsigned int secp256k1_scalar_get_bits(const secp256k1_scalar *a, unsigned int offset, unsigned int count) {