Operating system:
6.1.0-12-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.52-1 (2023-09-07) x86_64 GNU/Linux
What I'm trying to do:
I'm trying to build one of this asio samples: https://github.com/chriskohlhoff/asio/tree/master/asio/src/examples/cpp11/ssl
How I am doing that:
g++ -o server -std=c++2a -std=gnu++2a -D__STDC_WANT_LIB_EXT1_\_ -DSTDC_WANT_LIB_EXT1 -DASIO_STANDALONE -lssl -lcrypto -pthread -gdwarf-3 -Idependencies/include/asio-1.24.0/include server.cpp
What do I get:
/usr/bin/ld: /tmp/ccH9beax.o: in function \`asio::error::detail::ssl_category::message\[abi:cxx11\](int) const':
/home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/error.ipp:38: undefined reference to \`ERR_reason_error_string'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/error.ipp:41: undefined reference to \`ERR_lib_error_string'
/usr/bin/ld: /tmp/ccH9beax.o: in function \`asio::ssl::context::bio_cleanup::\~bio_cleanup()':
/home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:35: undefined reference to \`BIO_free'
/usr/bin/ld: /tmp/ccH9beax.o: in function \`asio::ssl::context::context(asio::ssl::context_base::method)':
/home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:67: undefined reference to \`ERR_clear_error'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:94: undefined reference to \`TLS_method'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:94: undefined reference to \`SSL_CTX_new'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:97: undefined reference to \`SSL_CTX_ctrl'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:98: undefined reference to \`SSL_CTX_ctrl'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:102: undefined reference to \`TLS_client_method'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:102: undefined reference to \`SSL_CTX_new'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:105: undefined reference to \`SSL_CTX_ctrl'
/usr/bin/ld: /home/zapboard/dependencies/include/asio-1.24.0/include/asio/ssl/impl/context.ipp:106: undefined reference to \`SSL_CTX_ctrl'
...
I didn't paste whole log but I think that everyone would agree that this is linking problem with OpenSSL.
How did I try to solve the issue: When I execute: "apt search openssl" I see that I have following openssl packages installed:
openssl/stable,stable,stable-security,now 3.0.11-1~deb12u2 amd64 [installed]
Secure Sockets Layer toolkit - cryptographic utility
libssl3/stable,stable,stable-security,now 3.0.11-1~deb12u2 amd64 [installed]
Secure Sockets Layer toolkit - shared libraries
libssl-dev/stable,stable,stable-security,now 3.0.11-1~deb12u2 amd64 [installed]
Secure Sockets Layer toolkit - development files
I checked version of openssl and where it is installed:
root@kvm66:/usr/include/openssl# openssl version -a
OpenSSL 3.0.11 19 Sep 2023 (Library: OpenSSL 3.0.11 19 Sep 2023)
built on: Mon Oct 23 17:52:22 2023 UTC
platform: debian-amd64
options: bn(64,64)
compiler: gcc -fPIC -pthread -m64 -Wa,--noexecstack -Wall -fzero-call-used-regs=used-gpr -DOPENSSL_TLS_SECURITY_LEVEL=2 -Wa,--noexecstack -g -O2 -ffile-prefix-map=/build/reproducible-path/openssl-3.0.11=. -fstack-protector-strong -Wformat -Werror=format-security -DOPENSSL_USE_NODELETE -DL_ENDIAN -DOPENSSL_PIC -DOPENSSL_BUILDING_OPENSSL -DNDEBUG -Wdate-time -D_FORTIFY_SOURCE=2
OPENSSLDIR: "/usr/lib/ssl"
ENGINESDIR: "/usr/lib/x86_64-linux-gnu/engines-3"
MODULESDIR: "/usr/lib/x86_64-linux-gnu/ossl-modules"
Seeding source: os-specific
CPUINFO: OPENSSL_ia32cap=0xfffa32234f8bffff:0x1cd19e4fbb
root@kvm66:/usr/include/openssl# whereis openssl
openssl: /usr/bin/openssl /usr/include/openssl /usr/share/man/man1/openssl.1ssl.gz
Then I checked linker search paths:
root@kvm66:/home/zapboard# ldconfig -v
ldconfig: Can't stat /usr/local/lib/x86_64-linux-gnu: No such file or directory
ldconfig: Path `/usr/lib/x86_64-linux-gnu' given more than once
(from /etc/ld.so.conf.d/x86_64-linux-gnu.conf:4 and /etc/ld.so.conf.d/x86_64-linux-gnu.conf:3)
ldconfig: Path `/lib/x86_64-linux-gnu' given more than once
(from <builtin>:0 and /etc/ld.so.conf.d/x86_64-linux-gnu.conf:3)
ldconfig: Path `/usr/lib/x86_64-linux-gnu' given more than once
(from <builtin>:0 and /etc/ld.so.conf.d/x86_64-linux-gnu.conf:3)
ldconfig: Path `/usr/lib' given more than once
(from <builtin>:0 and <builtin>:0)
/usr/local/lib: (from /etc/ld.so.conf.d/libc.conf:2)
/lib/x86_64-linux-gnu: (from /etc/ld.so.conf.d/x86_64-linux-gnu.conf:3)
libpcre2-8.so.0 -> libpcre2-8.so.0.11.2
libnss_compat.so.2 -> libnss_compat.so.2
ldconfig: /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 is the dynamic linker, ignoring
ld-linux-x86-64.so.2 -> ld-linux-x86-64.so.2
libgprofng.so.0 -> libgprofng.so.0.0.0
libabsl_cordz_functions.so.20220623 -> libabsl_cordz_functions.so.20220623.0.0
libbind9-9.18.19-1~deb12u1-Debian.so -> libbind9-9.18.19-1~deb12u1-Debian.so
libisccfg-9.18.19-1~deb12u1-Debian.so -> libisccfg-9.18.19-1~deb12u1-Debian.so
liblmdb.so.0 -> liblmdb.so.0.0.0
libssl.so.3 -> libssl.so.3
libirs-9.18.19-1~deb12u1-Debian.so -> libirs-9.18.19-1~deb12u1-Debian.so
librt.so.1 -> librt.so.1
libcrypto.so.3 -> libcrypto.so.3
libpcprofile.so -> libpcprofile.so
libsepol.so.2 -> libsepol.so.2
libabsl_demangle_internal.so.20220623 -> libabsl_demangle_internal.so.20220623.0.0
...
It's not whole log but I see that libssl.so.3 and libcrypto.so.3 can be found. In /lib/x86_64-linux-gnu/ when executing:
root@kvm66:/usr/lib/x86_64-linux-gnu# ls -la
-rw-r--r-- 1 root root 1231052 Oct 23 19:52 libssl.a
lrwxrwxrwx 1 root root 11 Oct 23 19:52 libssl.so -> libssl.so.3
-rw-r--r-- 1 root root 696352 Oct 23 19:52 libssl.so.3
-rw-r--r-- 1 root root 9071956 Oct 23 19:52 libcrypto.a
lrwxrwxrwx 1 root root 14 Oct 23 19:52 libcrypto.so -> libcrypto.so.3
-rw-r--r-- 1 root root 4713752 Oct 23 19:52 libcrypto.so.3
If libs can be found I came to conclusion that there is something wrong with symbols, so I displayed them with:
root@kvm66:/lib/x86_64-linux-gnu# nm -gD libssl.so.3
0000000000025580 T DTLS_method@@OPENSSL_3.0.0
0000000000036160 T SSL_ctrl@@OPENSSL_3.0.0
000000000003c8f0 T SSL_CTX_new@@OPENSSL_3.0.0
Few of symols previously marked as undefined reference are placed in this so file, but I have compared it with OpenSSL lib from Alma Linux where I built this sample with OpenSSL 1.1
[root@kvm54 lib64]# nm -gD libssl.so
00000000000225f0 T DTLS_method
0000000000039fa0 T SSL_ctrl
000000000003b310 T SSL_CTX_new
I think that problem has something to do with symbol naming. I also previously built that sample on Windows where I use OpenSSL 3.2.0 instead OpenSSL 1.1, so I know that it supposed to work with OpenSSL 3.
My question is: Is there any special flag to use OpenSSL 3 with asio on linux (should symbol names look like that, I mean that @@OPENSSL_3.0.0 at the end of symbol name) or Is there any other cause of linker not seeing symbols ?