feedc0de/wolfssl
1
0
Fork 0
forked from wolfSSL/wolfssl
Code Pull Requests Activity

sp_lcm small stack: fix size of temporary

Browse Source 
Temporary sp_int needs to be allocated to be 1 digit larger than a or b
for the div operation.
Change sp_div to check sizes of r and rem when passed in.
Fix sp_invmod, sp_gcm, sp_submod to use temporary sp_int sizes that work
with calls to sp_div().
This commit is contained in:
Sean Parkinson
2021-02-15 09:48:18 +10:00
parent 505514415d
commit e187a74b1c
1 changed files with 18 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
wolfcrypt/src/sp_int.c
View File

@ -4014,7 +4014,11 @@ int sp_submod(sp_int* a, sp_int* b, sp_int* m, sp_int* r)
{
#ifndef WOLFSSL_SP_INT_NEGATIVE
int err = MP_OKAY;
DECL_SP_INT_ARRAY(t, (m == NULL) ? 1 : m->used + 1, 2);
int used = ((a == NULL) || (b == NULL) || (m == NULL)) ? 1 :
((a->used >= m->used) ?
((a->used >= b->used) ? (a->used + 1) : (b->used + 1)) :
((b->used >= m->used)) ? (b->used + 1) : (m->used + 1));
DECL_SP_INT_ARRAY(t, used, 2);
if ((a == NULL) || (b == NULL) || (m == NULL) || (r == NULL)) {
err = MP_VAL;
@ -4026,7 +4030,7 @@ int sp_submod(sp_int* a, sp_int* b, sp_int* m, sp_int* r)
sp_print(m, "m");
}
ALLOC_SP_INT_ARRAY(t, m->used + 1, 2, err, NULL);
ALLOC_SP_INT_ARRAY(t, used, 2, err, NULL);
if (err == MP_OKAY) {
if (_sp_cmp(a, m) == MP_GT) {
err = sp_mod(a, m, t[0]);
@ -4436,6 +4440,12 @@ int sp_div(sp_int* a, sp_int* d, sp_int* r, sp_int* rem)
if ((err == MP_OKAY) && sp_iszero(d)) {
err = MP_VAL;
}
if ((err == MP_OKAY) && (r != NULL) && (r->size < a->used - d->used + 2)) {
err = MP_VAL;
}
if ((err == MP_OKAY) && (rem != NULL) && (rem->size < a->used + 1)) {
err = MP_VAL;
}
if (0 && (err == MP_OKAY)) {
sp_print(a, "a");
@ -7721,7 +7731,9 @@ int sp_invmod(sp_int* a, sp_int* m, sp_int* r)
sp_int* v;
sp_int* b;
sp_int* c;
DECL_SP_INT_ARRAY(t, (m == NULL) ? 0 : m->used + 1, 4);
int used = ((m == NULL) || (a == NULL)) ? 1 :
((m->used >= a->used) ? m->used + 1 : a->used + 1);
DECL_SP_INT_ARRAY(t, used, 4);
if ((a == NULL) || (m == NULL) || (r == NULL)) {
err = MP_VAL;
@ -7739,7 +7751,7 @@ int sp_invmod(sp_int* a, sp_int* m, sp_int* r)
v = t[1];
b = t[2];
c = t[3];
sp_init_size(v, m->used + 1);
sp_init_size(v, used + 1);
if (_sp_cmp_abs(a, m) != MP_LT) {
err = sp_mod(a, m, v);
@ -13245,7 +13257,7 @@ int sp_gcd(sp_int* a, sp_int* b, sp_int* r)
sp_int* u = NULL;
sp_int* v = NULL;
sp_int* t = NULL;
int used = (a->used >= b->used) ? a->used : b->used;
int used = (a->used >= b->used) ? a->used + 1 : b->used + 1;
DECL_SP_INT_ARRAY(d, used, 3);
ALLOC_SP_INT_ARRAY(d, used, 3, err, NULL);
@ -13336,7 +13348,7 @@ int sp_lcm(sp_int* a, sp_int* b, sp_int* r)
{
int err = MP_OKAY;
int used = ((a == NULL) || (b == NULL)) ? 1 :
(a->used >= b->used ? a->used : b->used);
(a->used >= b->used ? a->used + 1: b->used + 1);
DECL_SP_INT_ARRAY(t, used, 2);
if ((a == NULL) || (b == NULL) || (r == NULL)) {