commit 71651ea4aa507ee50865bd9584873e0c9a422c14 Author: Fabian Keil fk@fabiankeil.de Date: Tue Apr 7 16:36:05 2015 +0200

Complain if net.inet.ip.random_id is not set on FreeBSD-based servers

Apparently a couple of operators haven't gotten the memos [0] yet and it looks like FreeBSD's default value will not change any time soon [1].

[0]: https://lists.torproject.org/pipermail/tor-relays/2014-March/004199.html https://lists.torproject.org/pipermail/tor-relays/2014-November/005687.html https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=195828

[1]: https://lists.freebsd.org/pipermail/freebsd-net/2015-April/041942.html --- src/app/config/config.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+)

diff --git a/src/app/config/config.c b/src/app/config/config.c index 45a23d67d..56fca1549 100644 --- a/src/app/config/config.c +++ b/src/app/config/config.c @@ -157,6 +157,10 @@ #include "core/or/connection_st.h" #include "core/or/port_cfg_st.h"

+#ifdef __FreeBSD__ +#include <sys/sysctl.h> +#endif + #ifdef HAVE_SYSTEMD # if defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__) /* Systemd's use of gcc's __INCLUDE_LEVEL__ extension macro appears to confuse @@ -3383,6 +3387,23 @@ options_validate(or_options_t *old_options, or_options_t *options, if (ContactInfo && !string_is_utf8(ContactInfo, strlen(ContactInfo))) REJECT("ContactInfo config option must be UTF-8.");

+#ifdef __FreeBSD__ + if (server_mode(options)) { + int random_id_state; + size_t state_size = sizeof(random_id_state); + + if (sysctlbyname("net.inet.ip.random_id", &random_id_state, + &state_size, NULL, 0)) { + log_warn(LD_CONFIG, + "Failed to figure out if IP ids are randomized."); + } else if (random_id_state == 0) { + log_warn(LD_CONFIG, "Looks like IP ids are not randomized. " + "Please consider setting the net.inet.ip.random_id sysctl, " + "so your relay makes it harder to figure out how busy it is."); + } + } +#endif + /* Special case on first boot if no Log options are given. */ if (!options->Logs && !options->RunAsDaemon && !from_setconf) { if (quiet_level == 0)