1 files changed, 15 insertions, 1 deletions

diff --git a/src/lib/libcrypto/dsa/dsa_ameth.c b/src/lib/libcrypto/dsa/dsa_ameth.c
index 4e8f4ac825..eb4d5d2dcd 100644
--- a/src/lib/libcrypto/dsa/dsa_ameth.c
+++ b/src/lib/libcrypto/dsa/dsa_ameth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dsa_ameth.c,v 1.32 2022/01/15 04:02:37 tb Exp $ */
+/* $OpenBSD: dsa_ameth.c,v 1.33 2022/02/24 08:31:11 tb Exp $ */
 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project 2006.
  */
@@ -480,12 +480,26 @@ old_dsa_priv_decode(EVP_PKEY *pkey, const unsigned char **pder, int derlen)
         DSA *dsa;
         BN_CTX *ctx = NULL;
         BIGNUM *j, *p1, *newp1;
+        int qbits;
 
         if (!(dsa = d2i_DSAPrivateKey(NULL, pder, derlen))) {
                 DSAerror(ERR_R_DSA_LIB);
                 return 0;
         }
 
+        DSA_print_fp(stdout, dsa, 0);
+
+        /* FIPS 186-3 allows only three different sizes for q. */
+        qbits = BN_num_bits(dsa->q);
+        if (qbits != 160 && qbits != 224 && qbits != 256) {
+                DSAerror(DSA_R_BAD_Q_VALUE);
+                goto err;
+        }
+        if (BN_num_bits(dsa->p) > OPENSSL_DSA_MAX_MODULUS_BITS) {
+                DSAerror(DSA_R_MODULUS_TOO_LARGE);
+                goto err;
+        }
+
         ctx = BN_CTX_new();
         if (ctx == NULL)
                 goto err;