From 1a6921092423f2ba215c73fdc7f87a5abc189a76 Mon Sep 17 00:00:00 2001
From: jsing <jsing@openbsd.org>
Date: Tue, 20 Feb 2018 17:15:27 +0000
Subject: [PATCH] Provide BIO_get_new_index().

Based on BoringSSL.
---
 lib/libcrypto/Symbols.list  |  1 +
 lib/libcrypto/bio/bio.h     |  9 ++++++++-
 lib/libcrypto/bio/bio_lib.c | 16 +++++++++++++++-
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/lib/libcrypto/Symbols.list b/lib/libcrypto/Symbols.list
index 23030bdb155..2252220278c 100644
--- a/lib/libcrypto/Symbols.list
+++ b/lib/libcrypto/Symbols.list
@@ -280,6 +280,7 @@ BIO_get_data
 BIO_get_ex_data
 BIO_get_ex_new_index
 BIO_get_host_ip
+BIO_get_new_index
 BIO_get_port
 BIO_get_retry_BIO
 BIO_get_retry_reason
diff --git a/lib/libcrypto/bio/bio.h b/lib/libcrypto/bio/bio.h
index 8efeba20053..1d34f082eec 100644
--- a/lib/libcrypto/bio/bio.h
+++ b/lib/libcrypto/bio/bio.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: bio.h,v 1.33 2018/02/18 12:59:06 tb Exp $ */
+/* $OpenBSD: bio.h,v 1.34 2018/02/20 17:15:27 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -103,6 +103,12 @@ extern "C" {
 #define BIO_TYPE_FILTER		0x0200
 #define BIO_TYPE_SOURCE_SINK	0x0400
 
+/*
+ * BIO_TYPE_START is the first user-allocated BIO type. No pre-defined type,
+ * flag bits aside, may exceed this value.
+ */
+#define BIO_TYPE_START 128
+
 /* BIO_FILENAME_READ|BIO_CLOSE to open or close on free.
  * BIO_set_fp(in,stdin,BIO_NOCLOSE); */
 #define BIO_NOCLOSE		0x00
@@ -580,6 +586,7 @@ int
 BIO_asn1_get_suffix(BIO *b, asn1_ps_func **psuffix,
 asn1_ps_func **psuffix_free);
 
+int BIO_get_new_index(void);
 BIO_METHOD *BIO_s_file(void );
 BIO *BIO_new_file(const char *filename, const char *mode);
 BIO *BIO_new_fp(FILE *stream, int close_flag);
diff --git a/lib/libcrypto/bio/bio_lib.c b/lib/libcrypto/bio/bio_lib.c
index 4e5405d6afb..b2acd01342a 100644
--- a/lib/libcrypto/bio/bio_lib.c
+++ b/lib/libcrypto/bio/bio_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: bio_lib.c,v 1.24 2018/02/18 12:58:25 tb Exp $ */
+/* $OpenBSD: bio_lib.c,v 1.25 2018/02/20 17:15:27 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -64,6 +64,20 @@
 #include <openssl/err.h>
 #include <openssl/stack.h>
 
+int
+BIO_get_new_index(void)
+{
+	static int bio_type_index = BIO_TYPE_START;
+	int index;
+
+	/* The index will collide with the BIO flag bits if it exceeds 255. */
+	index = CRYPTO_add(&bio_type_index, 1, CRYPTO_LOCK_BIO);
+	if (index > 255)
+		return -1;
+
+	return index;
+}
+
 BIO *
 BIO_new(BIO_METHOD *method)
 {
-- 
2.20.1