Build failure when WITH_TLS=OFF, Linux

[bmparr]

Minor build issue on GNU/Linux:
mkdir build
cd build
cmake -DWITH_TLS:BOOL=OFF ..
make

mosquitto-1.6.1/src/net.c: In function ‘net__socket_listen’:
mosquitto-1.6.1/src/net.c:442:2: error: ‘rc’ undeclared (first use in this function)

ln 421: 'int rc;' is hidden in #ifdef/#endif

[ralight]

Thank you!

Is this option important to you? I've been considering removing the option to compile without TLS support.

[bmparr]

Hi Roger, It only came up with 1.6.1. One of our target systems is CentOS6. For 1.6.1, it seams that the version of openssl (1.0.1e) on CentOS6 is a bit tool old. On CentOS7, openssl is 1.0.2 and it compiles fine, but on CentOS6 I see: ../lib/libmosquitto.so.1.6.1: undefined reference to `SSL_CTX_set_alpn_protos' (don't have any other versions of openssl installed) I didn't see this with mosquitto 1.5.8. We use mosquitto in a closed system and don't use authentication. I turned TLS off which got me around the build issue. I didn't dig beyond getting it to build. We do plan to phase out CentOS6 but it will take at least a year. We can always freeze on 1.6.x for CentOS6. Regards, Bruce

…

On Mon, Apr 29, 2019 at 4:58 PM Roger Light ***@***.***> wrote: Thank you! Is this option important to you? I've been considering removing the option to compile without TLS support. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#1250 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AADA35YC6DZQ6SJX2NDP45DPS5VPZANCNFSM4HJF35XA> .

[ralight]

Thanks for the explanation Bruce. Yes, there isn't support for OpenSSL 1.0.1 because it is not supported by OpenSSL itself. It's fairly straightforward to remove the ALPN code, it doesn't touch much, but I wouldn't want to guarantee there isn't something else that is going to cause problems for you on 1.0.1. There's not a big rush to remove the option of WITH_TLS=no, so I can put that back for a while, probably to 2.0.

[karlp]

hijacking a little, but there's quite a few peole on openwrt using the -nossl package variant, as the openssl lib is too big for them, and they're using them in closed internal systems. You can search for "mosquitto" on https://downloads.openwrt.org/stats/awstats.downloads2.lede-project.org.allextra2.html (but that's not a long term list just people that download post install, rather than build their own)

[ralight]

@karlp That's good to know, thanks.

[karlp]

Heading off into the woods, but mbed-tls has become the "goto" "small" tls option. If there was an mbed-tls option, I could convince people that mosquitto is TLS ONLY but openssl is a hard sell.