openssh/openssh-fips-ensure-approved-moduli.patch

79 lines
1.7 KiB
Diff

commit 15c95d6eb2e8bc549719578c9a16541015363360
Author: Hans Petter Jansson <hpj@hpjansson.org>
Date: Mon Oct 26 22:26:46 2020 +0100
Ensure DHGs are approved in FIPS mode using OpenSSL's DH_check_params()
Index: openssh-8.8p1/dh.c
===================================================================
--- openssh-8.8p1.orig/dh.c
+++ openssh-8.8p1/dh.c
@@ -155,6 +155,28 @@ parse_prime(int linenum, char *line, str
return 0;
}
+static int
+dhg_is_approved(const struct dhgroup *dhg)
+{
+ BIGNUM *g, *p;
+ DH *dh;
+ int dh_status;
+ int is_ok = 0;
+
+ /* DH_set0_pqg() transfers ownership of the bignums, so we
+ * make temporary copies here for simplicity. */
+ g = BN_dup(dhg->g);
+ p = BN_dup(dhg->p);
+ dh = dh_new_group(g, p);
+
+ if (dh) {
+ is_ok = DH_check_params(dh, &dh_status);
+ }
+
+ DH_free(dh);
+ return is_ok;
+}
+
DH *
choose_dh(int min, int wantbits, int max)
{
@@ -173,12 +195,20 @@ choose_dh(int min, int wantbits, int max
linenum = 0;
best = bestcount = 0;
while (getline(&line, &linesize, f) != -1) {
+ int dhg_is_ok;
+
linenum++;
if (!parse_prime(linenum, line, &dhg))
continue;
+
+ dhg_is_ok = dhg_is_approved(&dhg);
+
BN_clear_free(dhg.g);
BN_clear_free(dhg.p);
+ if (!dhg_is_ok)
+ continue;
+
if (dhg.size > max || dhg.size < min)
continue;
@@ -206,10 +236,16 @@ choose_dh(int min, int wantbits, int max
linenum = 0;
bestcount = 0;
while (getline(&line, &linesize, f) != -1) {
+ int dhg_is_ok;
+
linenum++;
if (!parse_prime(linenum, line, &dhg))
continue;
- if ((dhg.size > max || dhg.size < min) ||
+
+ dhg_is_ok = dhg_is_approved(&dhg);
+
+ if (!dhg_is_ok ||
+ (dhg.size > max || dhg.size < min) ||
dhg.size != best ||
bestcount++ != which) {
BN_clear_free(dhg.g);