Prepare to provide DSA_meth_{get0,set1}_name()

Also follow OpenSSL by making the name non-const to avoid ugly casting.
Used by OpenSC's pkcs11-helper, as reported by Fabrice Fontaine in
https://github.com/libressl-portable/openbsd/issues/130

ok jsing sthen

3 files changed, 35 insertions, 8 deletions

diff --git a/lib/libcrypto/dsa/dsa.h b/lib/libcrypto/dsa/dsa.h
index 2ee27d775f3..12b1faadf3d 100644
--- a/lib/libcrypto/dsa/dsa.h
+++ b/lib/libcrypto/dsa/dsa.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: dsa.h,v 1.36 2022/06/27 12:28:46 tb Exp $ */
+/* $OpenBSD: dsa.h,v 1.37 2022/07/04 12:22:32 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -222,6 +222,10 @@ ENGINE *DSA_get0_engine(DSA *d);
 DSA_METHOD *DSA_meth_new(const char *name, int flags);
 void DSA_meth_free(DSA_METHOD *meth);
 DSA_METHOD *DSA_meth_dup(const DSA_METHOD *meth);
+#ifdef LIBRESSL_INTERNAL
+const char *DSA_meth_get0_name(const DSA_METHOD *meth);
+int DSA_meth_set1_name(DSA_METHOD *meth, const char *name);
+#endif
 int DSA_meth_set_sign(DSA_METHOD *meth,
     DSA_SIG *(*sign)(const unsigned char *, int, DSA *));
 int DSA_meth_set_finish(DSA_METHOD *meth, int (*finish)(DSA *));
diff --git a/lib/libcrypto/dsa/dsa_locl.h b/lib/libcrypto/dsa/dsa_locl.h
index 299c67a6b90..f78ff818abb 100644
--- a/lib/libcrypto/dsa/dsa_locl.h
+++ b/lib/libcrypto/dsa/dsa_locl.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: dsa_locl.h,v 1.5 2022/01/14 08:29:06 tb Exp $ */
+/* $OpenBSD: dsa_locl.h,v 1.6 2022/07/04 12:22:32 tb Exp $ */
 /* ====================================================================
  * Copyright (c) 2007 The OpenSSL Project.  All rights reserved.
  *
@@ -63,7 +63,7 @@ struct DSA_SIG_st {
 } /* DSA_SIG */;
 
 struct dsa_method {
-	const char *name;
+	char *name;
 	DSA_SIG *(*dsa_do_sign)(const unsigned char *dgst, int dlen, DSA *dsa);
 	int (*dsa_sign_setup)(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp,
 	    BIGNUM **rp);
diff --git a/lib/libcrypto/dsa/dsa_meth.c b/lib/libcrypto/dsa/dsa_meth.c
index cd232835ebd..2cb0426d430 100644
--- a/lib/libcrypto/dsa/dsa_meth.c
+++ b/lib/libcrypto/dsa/dsa_meth.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dsa_meth.c,v 1.3 2022/05/07 10:31:54 tb Exp $	*/
+/*	$OpenBSD: dsa_meth.c,v 1.4 2022/07/04 12:22:32 tb Exp $	*/
 /*
  * Copyright (c) 2018 Theo Buehler <tb@openbsd.org>
  *
@@ -42,10 +42,11 @@ DSA_meth_new(const char *name, int flags)
 void
 DSA_meth_free(DSA_METHOD *meth)
 {
-	if (meth != NULL) {
-		free((char *)meth->name);
-		free(meth);
-	}
+	if (meth == NULL)
+		return
+
+	free(meth->name);
+	free(meth);
 }
 
 DSA_METHOD *
@@ -64,6 +65,28 @@ DSA_meth_dup(const DSA_METHOD *meth)
 	return copy;
 }
 
+const char *
+DSA_meth_get0_name(const DSA_METHOD *meth)
+{
+	return meth->name;
+}
+
+int
+DSA_meth_set1_name(DSA_METHOD *meth, const char *name)
+{
+	char *new_name;
+
+	if ((new_name = strdup(name)) == NULL) {
+		DSAerror(ERR_R_MALLOC_FAILURE);
+		return 0;
+	}
+
+	free(meth->name);
+	meth->name = new_name;
+
+	return 1;
+}
+
 int
 DSA_meth_set_sign(DSA_METHOD *meth,
     DSA_SIG *(*sign)(const unsigned char *, int, DSA *))