mtr 0.96

• IPv6 UDP checksums like IPv4 but with IPv6 pseudoheader

  Fixes a problem where both source and destination port are supplied on the commandline, this lead to packets not showing up any more due to checksum being different.

• Adjust MIN_PORT to match other implementations

  Port 33434 is the IANA-reserved port for traceroute. It also seems to be the most common start port. The following implementations, and likely others, use it as their start port:

  • Apple macOS traceroute
  • FreeBSD traceroute
  • GNU inetutils-traceroute
  • Modern traceroute for Linux
  • OpenBSD traceroute

  The benefit to using a standard starting port is that some firewalls may have these ports allowed, whereas other ports may be blocked, so there is a greater probability the probe will succeed.

• Use addrs for static host ordering in curses

  Change d2552ca has the side effect of moving hosts around in the multipath view, as the last host to reply to a packet was set as addr. Using addrs[0] istead of addr to draw the first host keeps the ordering deterministic, in order of first reply.

• Add --max-display-paths option

  It is not unknown to have datacenters with over 8 ECMP paths between two hops. Expand the maximum number of ECMP hosts stored in addrs to 128, and add a new option to control the number to display, defaulting to the old MAX_PATHS of 8

• Set SO_BINDTODEVICE for -I

  This is done by traceroute and other tools as well. It requires CAP_NET_RAW, but without it the -I option doesn't seem to have any effect.

• Check if SO_BINDTODEVICE is defined

• Add help info for option -E

• Make interactive and non-interactive exit code the same

  Before this change the report gave successful exit value when destination hostname could not be found.

• Fix the sizes passed into snprintf

• Add option to use custom ipinfo provider

• Implement ASN lookups in well-known NAT64 prefix

• Add error code ETIMEOUT(110) handle logic

• Change UDP and ICMP sockets binding to accept a source IP from the -a CLI option

• Fix capability management, retain CAP_NET_ADMIN

  Modify the capability-dropping logic to specifically retain CAP_NET_ADMIN if it is initially provided, in adherence to least-privilege principles.

• Fix interface binding by retaining CAP_NET_RAW

  Addresses an issue where mtr would fail with EPERM because setting the SO_BINDTODEVICE socket option requires the CAP_NET_RAW capability.

• Annotate set_privileged_socket_opt with UNUSED

  The set_privileged_socket_opt function is currently called only when SO_MARK or SO_BINDTODEVICE are defined. On systems that do not support either feature, set_privileged_socket_opt is expected to be unused. Adding an annotation suppresses compiler warnings.

• Drop capabilities when setsockopt errors

  Ensure that set_privileged_socket_opt drops capabilities even in the event that setsockopt returns an error.

• Use packet marking for IP address selection

  In certain scenarios, the routing policy database may affect packet routing. When selecting an address in mtr, assign a packet mark if SO_MARK is defined and a mark has been supplied.

• Support hexadecimal arguments for packet marking

  Packet marks are often specified in hexadecimal format. Update the strtonum_or_err function to parse both hexadecimal and decimal values.

• Add a compact mode in curses

• Handle EHOSTDOWN and refine error handling better granularity

• Prevent icmp_socket leak on error

• Change how confliciting first/max TTL works

• XML report: remove leading spaces

• Add braille graph support with --displaymode 3

• Set UTF-8 encoding for XML reports

• Increased max probes

• Implement addrcmp for AF_UNSPEC

  When mtr is compiled with IPv6 enabled, the GTK frontend sets the address family to AF_UNSPEC when changing destinations. However, addrcomp does not support this AF type, which causes all comparisons to not match. For the GTK frontend, this leads to a cascading failure when setting the destination to a host that does not resolve.

• Add protection against use of MTR_PACKET under special circumstances