On 12/08/2022 03:34, Imazu Setsuo wrote:
On 2022/08/10 18:44, Matt Caswell wrote:
On 10/08/2022 00:11, Imazu Setsuo wrote:
Hello, my name is Imazu.
I am using OpenSSL3.0.5 to develop a windows program.
When I call PEM_read_PrivateKey() I get the following error:
OPENSSL_Uplink(00007FF8011DD3E0,08): no OPENSSL_Applink
The source that calls PEM_read_PrivateKey() includes the following
sources.
#include <openssl/applink.c>
In the test program
test.exe --> my_appl.dll --> openssl.dll
, the above include is the source in my_appl.dll.
The depends tool (Dependency Walker) can check the entry of
OPENSSL_Applink.
By the way, if you describe "#include <openssl/applink.c>" in the source
inside test.exe, it will work.
However, I want to complete the processing within my_appl.dll.
Please tell me a good way.
Best regards.
The problem comes when your code opens a FILE* and then passes it for
use to OpenSSL. If your code and OpenSSL are using a different C runtime
then that's going to fail.
A possible workaround is not call PEM_read_PrivateKey() at all and
instead use PEM_read_bio_PrivateKey(). You can then (for example) load
the file into memory completely within your code and store the data in a
mem BIO (e.g. using BIO_new_mem_buf()). This removes the need to pass
FILE * pointers from one dll to another and avoids the problem.
Matt
hello.
After fixing it with your advice, it worked without any errors. Thank you.
I've been thinking about this for a while, what do you think of the
following?
The "HMODULE hModule" that can be referenced by DllMain is retained in
the variable (BASE_HANDLE) when the "DLL_PROCESS_ATTACH" condition occurs.
There'd probably have to be some call from the DLL into libcrypto
providing the HMODULE handle to use....but then what happens if the end
application is *also* using OpenSSL??
I suspect there is no good answer here.
Matt
