diff options
Diffstat (limited to 'doc/man3/BIO_s_mem.pod')
-rw-r--r-- | doc/man3/BIO_s_mem.pod | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/doc/man3/BIO_s_mem.pod b/doc/man3/BIO_s_mem.pod index 050d7786a6cf..2a5d423648db 100644 --- a/doc/man3/BIO_s_mem.pod +++ b/doc/man3/BIO_s_mem.pod @@ -88,6 +88,22 @@ a buffering BIO to the chain will speed up the process. Calling BIO_set_mem_buf() on a BIO created with BIO_new_secmem() will give undefined results, including perhaps a program crash. +Switching the memory BIO from read write to read only is not supported and +can give undefined results including a program crash. There are two notable +exceptions to the rule. The first one is to assign a static memory buffer +immediately after BIO creation and set the BIO as read only. + +The other supported sequence is to start with read write BIO then temporarily +switch it to read only and call BIO_reset() on the read only BIO immediately +before switching it back to read write. Before the BIO is freed it must be +switched back to the read write mode. + +Calling BIO_get_mem_ptr() on read only BIO will return a BUF_MEM that +contains only the remaining data to be read. If the close status of the +BIO is set to BIO_NOCLOSE, before freeing the BUF_MEM the data pointer +in it must be set to NULL as the data pointer does not point to an +allocated memory. + =head1 BUGS There should be an option to set the maximum size of a memory BIO. @@ -124,7 +140,7 @@ BIO_new_mem_buf() returns a valid B<BIO> structure on success or NULL on error. =head1 COPYRIGHT -Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved. +Copyright 2000-2019 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 |