i compiled openssl with no-zlib here is ldd of my client:
> ldd client linux-vdso.so.1 => (0x00007fff059ff000) libssl.so.1.0.0 => /lib64/libssl.so.1.0.0 (0x00007fefccdc9000) libcrypto.so.1.0.0 => /lib64/libcrypto.so.1.0.0 (0x00007fefcca17000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00007fefcc7fa000) libc.so.6 => /lib64/libc.so.6 (0x00007fefcc48d000) libdl.so.2 => /lib64/libdl.so.2 (0x00007fefcc289000) libz.so.1 => /lib64/libz.so.1 (0x00007fefcc071000) /lib64/ld-linux-x86-64.so.2 (0x00007fefcd025000) it is still using the default libraries; when the client runs in this environment, it suggests 2 compression methods in the handshake (NULL, and xxxx) then I change the LD_LIBRARY_PATH env and run again: > export LD_LIBRARY_PATH=/home/mike02/wrk/openssl/lib > ldd client linux-vdso.so.1 => (0x00007fff42cfa000) libssl.so.1.0.0 => /home/mike02/wrk/openssl/lib/libssl.so.1.0.0 (0x00007f76caf15000) libcrypto.so.1.0.0 => /home/mike02/wrk/openssl/lib/libcrypto.so.1.0.0 (0x00007f76cab34000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f76ca917000) libc.so.6 => /lib64/libc.so.6 (0x00007f76ca5aa000) libdl.so.2 => /lib64/libdl.so.2 (0x00007f76ca3a6000) /lib64/ld-linux-x86-64.so.2 (0x00007f76cb17f000) and in this environment (note that libz is missing), the client only suggests 1 compression method (NULL) in the handshake. So, compiling with no-zlib is not sufficient for turning off compression. It is also required to take specific actions to use the openssl libraries compiled with the no-zlib option at runtime. I expect that by using SSL_OP_NO_COMPRESSION, compression will suppressed regardless of the linkage of zlib, but I haven't tested that proposal yet. On Tue, Dec 25, 2012 at 12:27 PM, Jeffrey Walton <noloa...@gmail.com> wrote: > Hi All, > > Is it sufficient to use -no-zlib to turn off SSL/TLS compression? Or > is compression available through other libraries? > > Jeff > ______________________________________________________________________ > OpenSSL Project http://www.openssl.org > User Support Mailing List openssl-users@openssl.org > Automated List Manager majord...@openssl.org >