From: Matt Caswell <matt@openssl.org>
Date: Fri, 3 May 2019 14:56:08 +0000 (+0100)
Subject: Reject obviously invalid DSA parameters during signing
X-Git-Tag: OpenSSL_1_1_1c~24
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=8f506274029903457c5f1d8663a012763f55cd37;p=oweals%2Fopenssl.git

Reject obviously invalid DSA parameters during signing

Fixes #8875

Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8876)

(cherry picked from commit 9acbe07d2300d34a7ea846d9756f33b4595e32fb)
---

diff --git a/crypto/dsa/dsa_ossl.c b/crypto/dsa/dsa_ossl.c
index 7a0b0874c5..0c22d41361 100644
--- a/crypto/dsa/dsa_ossl.c
+++ b/crypto/dsa/dsa_ossl.c
@@ -190,6 +190,12 @@ static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in,
         return 0;
     }
 
+    /* Reject obviously invalid parameters */
+    if (BN_is_zero(dsa->p) || BN_is_zero(dsa->q) || BN_is_zero(dsa->g)) {
+        DSAerr(DSA_F_DSA_SIGN_SETUP, DSA_R_INVALID_PARAMETERS);
+        return 0;
+    }
+
     k = BN_new();
     l = BN_new();
     if (k == NULL || l == NULL)