I'm trying to build OpenSSH 7.3p1 in a Linux box which has got installed an old OpenSSL version.
First of all I have successfully compiled OpenSSL 1.0.2h and installed in /opt/openssh-1.0.2h, not in /usr where resides the old OpenSSL version.
tar xzf openssl-1.0.2h.tar.gz
cd openssl-1.0.2h
./config --prefix=/opt/openssl-1.0.2h shared
make depend
make
make test
make install
Then I proceed with OpenSSH:
tar xzf openssh-7.3p1.tar.gz
cd openssh-7.3p1
./configure --prefix=/opt/openssh-7.3p1 --with-openssl=/opt/openssl-1.0.2h
But the configure scripts fails with the following error message:
checking OpenSSL header version... 0090802f (OpenSSL 0.9.8e-rhel5 01 Jul 2008)
checking OpenSSL library version... configure: error: OpenSSL >= 0.9.8f required (have "0090802f (OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008)")
The same message is displayed if I use --with-ssl-dir=/opt/openssl-1.0.2h/ssl
The tool findssl.sh (found in the subdirectory contrib) can find properly all OpenSSL versions. And its notes inside (comments) suggest to use CFLAGS to point out the desired library -- I quote:
# Now run findssl.sh. This should identify the headers and libraries
# present and their versions. You should be able to identify the
# libraries and headers used and adjust your CFLAGS or remove incorrect
# versions. The output will show OpenSSL's internal version identifier
# and should look something like:
Then I tried
./configure CFLAGS="-I/opt/openssl-1.0.2h/include" --prefix=/opt/openssh-7.3p1 --with-openssl=/opt/openssl-1.0.2h
This appears to work because it finds the new OpenSSL header version:
checking OpenSSL header version... 1000208f (OpenSSL 1.0.2h 3 May 2016)
checking OpenSSL library version... configure: error: OpenSSL >= 0.9.8f required (have "0090802f (OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008)")
Next step would be to supply additional options to locate the library files. But if I add LDFLAGS='-L/opt/openssl-1.0.2h/lib' or --with-ldflags='-L/opt/openssl-1.0.2h/lib', this is what I get:
checking OpenSSL header version... not found
configure: error: OpenSSL version header not found.
In summary, I do not know how to make configure use the new OpenSSL libraries.
update 1: if --with-ldflags='-L/opt/openssl-1.0.2h/ssl' is used instead of ···openssl-1.0.2h/lib then header version check works properly (see a few lines above), library version check still fails though.
update 2: I traced the problem and found it is related to shared libraries. From the config.log file I got the source code files conftest.c and confdef.h and the options used to build the runnable conftest:
#include "confdefs.h"
#include <stdio.h>
#include <string.h>
#include <openssl/opensslv.h>
#include <openssl/crypto.h>
#define DATA "conftest.ssllibver"
int
main ()
{
FILE *fd;
int rc;
fd = fopen(DATA,"w");
if (fd == NULL)
exit(1);
if ((rc = fprintf(fd, "%08lx (%s)\n", (unsigned long)SSLeay(),
SSLeay_version(SSLEAY_VERSION))) < 0)
exit(1);
exit(0);
}
This program stores the OpenSSL version as text in the file conftest.ssllibver. For debugging purposes I turned fprint(fd, into print( to print the data into the terminal.
The command line used to build the conftest program is:
# gcc -o conftest -I/opt/openssl-1.0.2h/include -Wall \
-Wpointer-arith -Wsign-compare -Wformat-security -Wno-pointer-sign \
-fno-strict-aliasing -D_FORTIFY_SOURCE=2 -ftrapv -fno-builtin-memset \
-fstack-protector-all -std=gnu99 -fPIE -Wl,-z,relro -Wl,-z,now \
-Wl,-z,noexecstack -fstack-protector-all -pie conftest.c \
-lcrypto -lrt -ldl -lutil -lz
# ldd conftest |grep libcrypto
libcrypto.so.6 => /lib64/libcrypto.so.6 (0x00002b5fc6c3e000)
Uses the old OpenSSL library.
When -L/opt/openssl-1.0.2h/lib is added as an argument, conftest cannot run because the dynamic loader (ld.so) cannot find libcrypto.so.1.0.0:
# ./conftest
./conftest: error while loading shared libraries: libcrypto.so.1.0.0: cannot open shared object file: No such file or directory
# ldd conftest | grep libcrypto
libcrypto.so.1.0.0 => not found
But when I make the LD_LIBRARY_PATH environment variable point to /opt/openssl-1.0.2h/lib, the dynamic loader finds the library file libcrypto.so.1.0.0 and thus the executable conftest works properly -- it uses the new OpenSSL library:
# export LD_LIBRARY_PATH=/opt/openssl-1.0.2h/lib
# ./conftest
1000208f (OpenSSL 1.0.2h 3 May 2016)
# ldd conftest
libcrypto.so.1.0.0 => /opt/openssl-1.0.2h/lib/libcrypto.so.1.0.0 (0x00002b450bf97000)
Export the LD_LIBRARY_PATH environment variable, which must hold the directory where new OpenSSL library files are, and run the configure script:
# export LD_LIBRARY_PATH=/opt/openssl-1.0.2h/lib
# ./configure CFLAGS="-I/opt/openssl-1.0.2h/include" \
--prefix=/opt/openssh-7.3p1 \
--with-ldflags="-L/opt/openssl-1.0.2h/lib"
Both commands can also be joined in just one:
# LD_LIBRARY_PATH=/opt/openssl-1.0.2h/lib ./configure \
CFLAGS="-I/opt/openssl-1.0.2h/include" \
--prefix=/opt/openssh-7.3p1 \
--with-ldflags="-L/opt/openssl-1.0.2h/lib"
And this is the outcome:
OpenSSH has been configured with the following options:
User binaries: /opt/openssh-7.3p1/bin
System binaries: /opt/openssh-7.3p1/sbin
Configuration files: /opt/openssh-7.3p1/etc
Askpass program: /opt/openssh-7.3p1/libexec/ssh-askpass
Manual pages: /opt/openssh-7.3p1/share/man/manX
PID file: /var/run
Privilege separation chroot path: /var/empty
sshd default user PATH: /usr/bin:/bin:/usr/sbin:/sbin:/opt/openssh-7.3p1/bin
Manpage format: doc
PAM support: no
OSF SIA support: no
KerberosV support: no
SELinux support: no
Smartcard support:
S/KEY support: no
MD5 password support: no
libedit support: no
Solaris process contract support: no
Solaris project support: no
Solaris privilege support: no
IP address in $DISPLAY hack: no
Translate v4 in v6 hack: yes
BSD Auth support: no
Random number source: OpenSSL internal ONLY
Privsep sandbox style: rlimit
Host: x86_64-unknown-linux-gnu
Compiler: gcc
Compiler flags: -I/opt/openssl-1.0.2h/include -Wall -Wpointer-arith -Wsign-compare \
-Wformat-security -Wno-pointer-sign -fno-strict-aliasing \
-D_FORTIFY_SOURCE=2 -ftrapv -fno-builtin-memset -fstack-protector-all \
-std=gnu99 -fPIE
Preprocessor flags:
Linker flags: -Wl,-z,relro -Wl,-z,now -Wl,-z,noexecstack -fstack-protector-all \
-L/opt/openssl-1.0.2h/lib -pie
Libraries: -lcrypto -lrt -ldl -lutil -lz -lcrypt -lresolv
It is highly recommended to use the LD_LIBRARY_PATH in the next steps make and make install; otherwise the make install will fail because the ssh-keygen command is run to generate the new host keys and it will not find the new OpenSSH library files:
mkdir /opt/openssh-7.3p1/etc
./ssh-keygen: error while loading shared libraries: libcrypto.so.1.0.0: cannot open shared object file: No such file or directory
make: *** [host-key] Error 127