factotum/libressl-portable
1
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

add infinite loop fix in BN_mod_sqrt

Browse Source
This commit is contained in:
Brent Cook 2022-03-12 11:26:23 -06:00
parent 2336a535c6
commit 74e92e5ecf
1 changed files with 38 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
patches/bn_sqrt.patch Normal file
View File

@ -0,0 +1,38 @@
--- crypto/bn/bn_sqrt.c.orig Fri Feb 18 16:30:39 2022
+++ crypto/bn/bn_sqrt.c Sat Mar 12 11:23:53 2022
@@ -351,21 +351,22 @@
goto vrfy;
}
-
- /* find smallest i such that b^(2^i) = 1 */
- i = 1;
- if (!BN_mod_sqr(t, b, p, ctx))
- goto end;
- while (!BN_is_one(t)) {
- i++;
- if (i == e) {
- BNerror(BN_R_NOT_A_SQUARE);
- goto end;
+ /* Find the smallest i with 0 < i < e such that b^(2^i) = 1. */
+ for (i = 1; i < e; i++) {
+ if (i == 1) {
+ if (!BN_mod_sqr(t, b, p, ctx))
+ goto end;
+ } else {
+ if (!BN_mod_sqr(t, t, p, ctx))
+ goto end;
}
- if (!BN_mod_mul(t, t, t, p, ctx))
- goto end;
+ if (BN_is_one(t))
+ break;
}
-
+ if (i >= e) {
+ BNerror(BN_R_NOT_A_SQUARE);
+ goto end;
+ }
/* t := y^2^(e - i - 1) */
if (!BN_copy(t, y))