Parse DHCP packets from a network interface

This fork of dhcpdump 1.8 by Edwin Groothuis, [email protected] (http://www.mavetju.org) collects in a single place bug-fixes and improvements collected over the last 10+ years.

• Fix the DHCP flags calculation
• Print option 82 content in a more usable way
• Avoid OOB access for the undefined string values
• Get ethertype in edian agnostic way
• Add/remove headers
• Use char for strings and uint8_t for binary data
• Let the Makefile use environment variables
• Spelling fixes
• Remove the unused strsep implementation
• Use a stricter filter for DHCP packets
• Add an option to dump packet content in HEX
• More consistent alignment of output
• Avoid extra new lines in parameter request list (option 55)
• Print client identifier as HEX+ASCII
• Print mac addresses with leading zeroes
• Add support for VLAN tagged traffic
• Add option to read traffic from pcap dump file
• Update option names and semantics from IANA (Rob Gill)
• Parse classless static routes option 121 and 249 using compact address and mask format (RFC3422) (Rob Gill)
• Parse PXE related options 93 and 94 (RFC4578 and errata) (Rob Gill)
• Parse stateless autoconfigure option 116 (RFC2563) (Rob Gill)