File openssl-CVE-2023-5678.patch of Package compat-openssl098.31475
From db925ae2e65d0d925adef429afc37f75bd1c2017 Mon Sep 17 00:00:00 2001
From: Richard Levitte <levitte@openssl.org>
Date: Fri, 20 Oct 2023 09:18:19 +0200
Subject: [PATCH] Make DH_check_pub_key() and DH_generate_key() safer yet
We already check for an excessively large P in DH_generate_key(), but not in
DH_check_pub_key(), and none of them check for an excessively large Q.
This change adds all the missing excessive size checks of P and Q.
It's to be noted that behaviours surrounding excessively sized P and Q
differ. DH_check() raises an error on the excessively sized P, but only
sets a flag for the excessively sized Q. This behaviour is mimicked in
DH_check_pub_key().
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Hugo Landau <hlandau@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/22518)
(cherry picked from commit ddeb4b6c6d527e54ce9a99cba785c0f7776e54b6)
---
crypto/dh/dh_check.c | 12 ++++++++++++
crypto/dh/dh_err.c | 3 ++-
crypto/dh/dh_key.c | 12 ++++++++++++
crypto/err/openssl.txt | 1 +
include/crypto/dherr.h | 2 +-
include/openssl/dh.h | 6 +++---
include/openssl/dherr.h | 3 ++-
7 files changed, 33 insertions(+), 6 deletions(-)
Index: openssl-0.9.8j/crypto/dh/dh.h
===================================================================
--- openssl-0.9.8j.orig/crypto/dh/dh.h
+++ openssl-0.9.8j/crypto/dh/dh.h
@@ -153,10 +153,13 @@ struct dh_st
#define DH_CHECK_P_NOT_SAFE_PRIME 0x02
#define DH_UNABLE_TO_CHECK_GENERATOR 0x04
#define DH_NOT_SUITABLE_GENERATOR 0x08
+#define DH_CHECK_INVALID_Q_VALUE 0x20 /* +DH_check_pub_key */
+#define DH_MODULUS_TOO_LARGE 0x100 /* +DH_check_pub_key */
/* DH_check_pub_key error codes */
#define DH_CHECK_PUBKEY_TOO_SMALL 0x01
#define DH_CHECK_PUBKEY_TOO_LARGE 0x02
+#define DH_CHECK_PUBKEY_INVALID 0x04
/* primes p where (p-1)/2 is prime too are called "safe"; we define
this for backward compatibility: */
@@ -229,6 +232,7 @@ void ERR_load_DH_strings(void);
#define DH_F_DHPARAMS_PRINT_FP 101
#define DH_F_DH_BUILTIN_GENPARAMS 106
#define DH_F_DH_CHECK 126
+#define DH_F_DH_CHECK_PUB_KEY 128
#define DH_F_DH_COMPUTE_KEY 107
#define DH_F_DH_GENERATE_KEY 108
#define DH_F_DH_GENERATE_PARAMETERS 109
@@ -242,6 +246,7 @@ void ERR_load_DH_strings(void);
#define DH_R_KEY_SIZE_TOO_SMALL 104
#define DH_R_MODULUS_TOO_LARGE 103
#define DH_R_NO_PRIVATE_VALUE 100
+#define DH_R_Q_TOO_LARGE 130
#ifdef __cplusplus
}
Index: openssl-0.9.8j/crypto/dh/dh_check.c
===================================================================
--- openssl-0.9.8j.orig/crypto/dh/dh_check.c
+++ openssl-0.9.8j/crypto/dh/dh_check.c
@@ -133,6 +133,18 @@ int DH_check_pub_key(const DH *dh, const
int ok=0;
BIGNUM *q=NULL;
+ /* Don't do any checks at all with an excessively large modulus */
+ if (BN_num_bits(dh->p) > OPENSSL_DH_CHECK_MAX_MODULUS_BITS) {
+ DHerr(DH_F_DH_CHECK_PUB_KEY, DH_R_MODULUS_TOO_LARGE);
+ *ret = DH_MODULUS_TOO_LARGE | DH_CHECK_PUBKEY_INVALID;
+ return 0;
+ }
+
+ if (dh->q != NULL && BN_ucmp(dh->p, dh->q) < 0) {
+ *ret |= DH_CHECK_INVALID_Q_VALUE | DH_CHECK_PUBKEY_INVALID;
+ return 1;
+ }
+
*ret=0;
q=BN_new();
if (q == NULL) goto err;
Index: openssl-0.9.8j/crypto/dh/dh_err.c
===================================================================
--- openssl-0.9.8j.orig/crypto/dh/dh_err.c
+++ openssl-0.9.8j/crypto/dh/dh_err.c
@@ -75,6 +75,7 @@ static ERR_STRING_DATA DH_str_functs[]=
{ERR_FUNC(DH_F_DHPARAMS_PRINT_FP), "DHparams_print_fp"},
{ERR_FUNC(DH_F_DH_BUILTIN_GENPARAMS), "DH_BUILTIN_GENPARAMS"},
{ERR_FUNC(DH_F_DH_CHECK), "DH_check"},
+{ERR_FUNC(DH_F_DH_CHECK_PUB_KEY), "DH_check_pub_key"},
{ERR_FUNC(DH_F_DH_COMPUTE_KEY), "DH_compute_key"},
{ERR_FUNC(DH_F_DH_GENERATE_KEY), "DH_generate_key"},
{ERR_FUNC(DH_F_DH_GENERATE_PARAMETERS), "DH_generate_parameters"},
@@ -91,6 +92,7 @@ static ERR_STRING_DATA DH_str_reasons[]=
{ERR_REASON(DH_R_KEY_SIZE_TOO_SMALL) ,"key size too small"},
{ERR_REASON(DH_R_MODULUS_TOO_LARGE) ,"modulus too large"},
{ERR_REASON(DH_R_NO_PRIVATE_VALUE) ,"no private value"},
+{ERR_REASON(DH_R_Q_TOO_LARGE) ,"q too large"},
{0,NULL}
};
Index: openssl-0.9.8j/crypto/dh/dh_key.c
===================================================================
--- openssl-0.9.8j.orig/crypto/dh/dh_key.c
+++ openssl-0.9.8j/crypto/dh/dh_key.c
@@ -80,6 +80,12 @@ int DH_generate_key(DH *dh)
int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
{
+ if (dh->q != NULL
+ && BN_num_bits(dh->q) > OPENSSL_DH_MAX_MODULUS_BITS) {
+ DHerr(DH_F_DH_COMPUTE_KEY, DH_R_Q_TOO_LARGE);
+ return 0;
+ }
+
return dh->meth->compute_key(key, pub_key, dh);
}
@@ -186,6 +192,12 @@ static int compute_key(unsigned char *ke
int ret= -1;
int check_result;
+ if (dh->q != NULL
+ && BN_num_bits(dh->q) > OPENSSL_DH_MAX_MODULUS_BITS) {
+ DHerr(DH_F_GENERATE_KEY, DH_R_Q_TOO_LARGE);
+ goto err;
+ }
+
if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS)
{
DHerr(DH_F_COMPUTE_KEY,DH_R_MODULUS_TOO_LARGE);
