Re: Problem with sftp server, static linking, pam and nss_ldap.

On 2010-01-31, at 13:58, Jilles Tjoelker wrote:

> On Sun, Jan 31, 2010 at 12:37:19PM +0100, Piotr Buliński wrote:
>> As you can see, it works great with dynamic linking, but if it's build with 
>> static linking it can't get user information from LDAP database.
> 
> Correct, NSS only works from dynamically-linked executables.

I didn't know that.

>> During the upgrade to OpenSSH 5.3p1 /head/secure/libexec/sftp-server/Makefile file changed a little bit:
>> 
>> revision 181111, Fri Aug 1 02:48:36 2008 UTC --->  revision 197679, Thu Oct 1 17:12:52 2009 UTC
>> LDADD=  -lssh -lcrypt -lcrypto -lz	     --->  LDADD=  -lcrypt -lcrypto -lz -static -lssh
> 
>> So I've tried to build sftp-server without -static switch, but it
>> result in failure like below:
> 
>> {volt}-{/usr/src/secure/libexec/sftp-server}% sudo make
>> Warning: Object directory not changed from original /usr/src/secure/libexec/sftp-server
>> cc -O2 -pipe -fomit-frame-pointer -march=opteron -I/usr/src/secure/libexec/sftp-server/../../../crypto/openssh -include ssh_namespace.h -std=gnu99 -Wno-pointer-sign -c /usr/src/secure/libexec/sftp-server/../../../crypto/openssh/sftp-server.c
>> cc -O2 -pipe -fomit-frame-pointer -march=opteron -I/usr/src/secure/libexec/sftp-server/../../../crypto/openssh -include ssh_namespace.h -std=gnu99 -Wno-pointer-sign -c /usr/src/secure/libexec/sftp-server/../../../crypto/openssh/sftp-common.c
>> cc -O2 -pipe -fomit-frame-pointer -march=opteron -I/usr/src/secure/libexec/sftp-server/../../../crypto/openssh -include ssh_namespace.h -std=gnu99 -Wno-pointer-sign -c /usr/src/secure/libexec/sftp-server/../../../crypto/openssh/sftp-server-main.c
>> cc -O2 -pipe -fomit-frame-pointer -march=opteron -I/usr/src/secure/libexec/sftp-server/../../../crypto/openssh -include ssh_namespace.h -std=gnu99 -Wno-pointer-sign  -o sftp-server sftp-server.o sftp-common.o sftp-server-main.o -lssh -lcrypt -lcrypto -lz
>> /usr/lib/libssh.so: undefined reference to `ssh_add_recv_bytes'
>> /usr/lib/libssh.so: undefined reference to `ssh_roaming_write'
>> /usr/lib/libssh.so: undefined reference to `ssh_roaming_read'
>> *** Error code 1
> 
>> Stop in /usr/src/secure/libexec/sftp-server.
>> {volt}-{/usr/src/secure/libexec/sftp-server}% 
> 
>> Do you have any idea how to make it works?
> 
> Apparently something broke so that sftp-server cannot link to libssh
> dynamically, even though scp and ssh can still use it.
> By changing the line in secure/libexec/sftp-server/Makefile to
> 
> LDADD=  -lcrypt -lcrypto -lz -Wl,-static -lssh -Wl,-call_shared
> 
> it links only libssh and its dependencies statically, which may be
> enough to fix your problem. This still links quite a lot more than
> libssh statically, I am not happy with it at all.

Thanks a lot! This solved my problem for now.
I'll be testing it this week.

Will you put this "patch" to the source tree of CURRENT
(or maybe it's good only as a temporary solution)?

Thanks again!
Regards
-- 
Piotr Buliński
Informatyka na Wydziale Elektrycznym
Politechnika Warszawska