From: Rich Salz <rsalz@openssl.org>
Date: Thu, 22 Jun 2017 18:00:06 +0000 (-0400)
Subject: Add fork handlers, based on pthread_atfork
X-Git-Tag: OpenSSL_1_1_1-pre1~1145
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=2915fe19a6676374c335d8c50eaaa4c940cf47d6;p=oweals%2Fopenssl.git
Add fork handlers, based on pthread_atfork
Only for Unix platforms
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3754)
---
diff --git a/crypto/include/internal/cryptlib.h b/crypto/include/internal/cryptlib.h
index f3ec9b67b8..d2ab720d34 100644
--- a/crypto/include/internal/cryptlib.h
+++ b/crypto/include/internal/cryptlib.h
@@ -66,6 +66,7 @@ extern unsigned int OPENSSL_ia32cap_P[];
void OPENSSL_showfatal(const char *fmta, ...);
extern int OPENSSL_NONPIC_relocated;
void crypto_cleanup_all_ex_data_int(void);
+int openssl_init_fork_handlers(void);
int openssl_strerror_r(int errnum, char *buf, size_t buflen);
# if !defined(OPENSSL_NO_STDIO)
diff --git a/crypto/init.c b/crypto/init.c
index e159a3dd0c..bc961718da 100644
--- a/crypto/init.c
+++ b/crypto/init.c
@@ -552,6 +552,10 @@ int OPENSSL_init_crypto(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings)
&& !RUN_ONCE(&add_all_digests, ossl_init_add_all_digests))
return 0;
+ if ((opts & OPENSSL_INIT_NO_ATFORK) == 0
+ && !openssl_init_fork_handlers())
+ return 0;
+
if ((opts & OPENSSL_INIT_NO_LOAD_CONFIG)
&& !RUN_ONCE(&config, ossl_init_no_config))
return 0;
@@ -677,3 +681,28 @@ int OPENSSL_atexit(void (*handler)(void))
return 1;
}
+
+#ifdef OPENSSL_SYS_UNIX
+/*
+ * The following three functions are for OpenSSL developers. This is
+ * where we set/reset state across fork (called via pthread_atfork when
+ * it exists, or manually by the application when it doesn't).
+ *
+ * WARNING! If you put code in either OPENSSL_fork_parent or
+ * OPENSSL_fork_child, you MUST MAKE SURE that they are async-signal-
+ * safe. See this link, for example:
+ * http://man7.org/linux/man-pages/man7/signal-safety.7.html
+ */
+
+void OPENSSL_fork_prepare(void)
+{
+}
+
+void OPENSSL_fork_parent(void)
+{
+}
+
+void OPENSSL_fork_child(void)
+{
+}
+#endif
diff --git a/crypto/threads_none.c b/crypto/threads_none.c
index 72bf25b0d5..39aadd0e98 100644
--- a/crypto/threads_none.c
+++ b/crypto/threads_none.c
@@ -121,4 +121,9 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
return 1;
}
+int openssl_init_fork_handlers(void)
+{
+ return 0;
+}
+
#endif
diff --git a/crypto/threads_pthread.c b/crypto/threads_pthread.c
index 151013e470..f7c792123b 100644
--- a/crypto/threads_pthread.c
+++ b/crypto/threads_pthread.c
@@ -8,6 +8,7 @@
*/
#include <openssl/crypto.h>
+#include <internal/cryptlib.h>
#if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && !defined(OPENSSL_SYS_WINDOWS)
@@ -168,4 +169,13 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
return 1;
}
+int openssl_init_fork_handlers(void)
+{
+# ifdef OPENSSL_SYS_UNIX
+ if (pthread_atfork(OPENSSL_fork_prepare,
+ OPENSSL_fork_parent, OPENSSL_fork_child) == 0)
+ return 1;
+# endif
+ return 0;
+}
#endif
diff --git a/crypto/threads_win.c b/crypto/threads_win.c
index 4e0de908ee..512e19f5f3 100644
--- a/crypto/threads_win.c
+++ b/crypto/threads_win.c
@@ -133,4 +133,9 @@ int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
return 1;
}
+int openssl_init_fork_handlers(void)
+{
+ return 0;
+}
+
#endif
diff --git a/doc/man3/OPENSSL_fork_prepare.pod b/doc/man3/OPENSSL_fork_prepare.pod
new file mode 100644
index 0000000000..4d05096c8d
--- /dev/null
+++ b/doc/man3/OPENSSL_fork_prepare.pod
@@ -0,0 +1,58 @@
+=pod
+
+=head1 NAME
+
+OPENSSL_fork_prepare,
+OPENSSL_fork_parent,
+OPENSSL_fork_child
+- OpenSSL fork handlers
+
+=head1 SYNOPSIS
+
+ #include <openssl/crypto.h>
+
+ void OPENSSL_fork_prepare(void);
+ void OPENSSL_fork_parent(void);
+ void OPENSSL_fork_child(void);
+
+=head1 DESCRIPTION
+
+OpenSSL has state that should be reset when a process forks. For example,
+the entropy pool used to generate random numbers (and therefore encryption
+keys) should not be shared across multiple programs.
+The OPENSSL_fork_prepare(), OPENSSL_fork_parent(), and OPENSSL_fork_child()
+functions are used to reset this internal state.
+
+Platforms without fork(2) will probably not need to use these functions.
+Platforms with fork(2) but without pthreads_atfork(3) will probably need
+to call them manually, as described in the following paragraph. Platforms
+such as Linux that have both functions will normally not need to call these
+functions as the OpenSSL library will do so automatically.
+
+L<OPENSSL_init_crypto(3)> will register these funtions with the appropriate
+hander, unless the B<OPENSSL_INIT_NO_ATFORK> flag is used. For those
+applications, these functions can be called directly. They should be used
+according to the calling sequence described by the pthreads_atfork(3)
+documentation, which is summarized here. OPENSSL_fork_prepare() should
+be called before a fork() is done. After the fork() returns, the parent
+process should call OPENSSL_fork_parent() and the child process should
+call OPENSSL_fork_child().
+
+=head1 SEE ALSO
+
+L<OPENSSL_init_crypto(3)>
+
+=head1 HISTORY
+
+These functions were added in OpenSSL 1.1.1.
+
+=head1 COPYRIGHT
+
+Copyright 2017 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License"). You may not use
+this file except in compliance with the License. You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
+
+=cut
diff --git a/doc/man3/OPENSSL_init_crypto.pod b/doc/man3/OPENSSL_init_crypto.pod
index fcc617ea4b..1ee7705b2b 100644
--- a/doc/man3/OPENSSL_init_crypto.pod
+++ b/doc/man3/OPENSSL_init_crypto.pod
@@ -150,6 +150,11 @@ With this option the library will automatically load and initialise all the
built in engines listed above with the exception of the openssl and dasync
engines. This not a default option.
+=item OPENSSL_INIT_NO_ATFORK
+
+With this option the library will not register its fork handlers.
+See OPENSSL_fork_prepare(3) for details.
+
=back
Multiple options may be combined together in a single call to
diff --git a/include/openssl/crypto.h b/include/openssl/crypto.h
index 5c7d1139d6..06ca40eba9 100644
--- a/include/openssl/crypto.h
+++ b/include/openssl/crypto.h
@@ -332,6 +332,11 @@ int FIPS_mode(void);
int FIPS_mode_set(int r);
void OPENSSL_init(void);
+# ifdef OPENSSL_SYS_UNIX
+void OPENSSL_fork_prepare(void);
+void OPENSSL_fork_parent(void);
+void OPENSSL_fork_child(void);
+# endif
struct tm *OPENSSL_gmtime(const time_t *timer, struct tm *result);
int OPENSSL_gmtime_adj(struct tm *tm, int offset_day, long offset_sec);
@@ -364,7 +369,8 @@ int CRYPTO_memcmp(const void * in_a, const void * in_b, size_t len);
# define OPENSSL_INIT_ENGINE_CAPI 0x00002000L
# define OPENSSL_INIT_ENGINE_PADLOCK 0x00004000L
# define OPENSSL_INIT_ENGINE_AFALG 0x00008000L
-/* OPENSSL_INIT flag 0x00010000 reserved for internal use */
+# define OPENSSL_INIT_reserved_internal 0x00010000L
+# define OPENSSL_INIT_NO_ATFORK 0x00020000L
/* OPENSSL_INIT flag range 0xfff00000 reserved for OPENSSL_init_ssl() */
/* Max OPENSSL_INIT flag value is 0x80000000 */
diff --git a/util/libcrypto.num b/util/libcrypto.num
index d734461a9b..c861878fb1 100644
--- a/util/libcrypto.num
+++ b/util/libcrypto.num
@@ -4342,3 +4342,6 @@ OSSL_STORE_INFO_set0_NAME_description 4284 1_1_1 EXIST::FUNCTION:
OSSL_STORE_INFO_get1_NAME_description 4285 1_1_1 EXIST::FUNCTION:
OSSL_STORE_do_all_loaders 4286 1_1_1 EXIST::FUNCTION:
OSSL_STORE_LOADER_get0_engine 4287 1_1_1 EXIST::FUNCTION:
+OPENSSL_fork_prepare 4288 1_1_1 EXIST:UNIX:FUNCTION:
+OPENSSL_fork_parent 4289 1_1_1 EXIST:UNIX:FUNCTION:
+OPENSSL_fork_child 4290 1_1_1 EXIST:UNIX:FUNCTION: