Following the current changes, future work will involve adding support for
options 138 and 139. I have not included these in this patch series because
the parsing for both requires significant code changes, which I believe
would be too much to review at once.
Regards,
Anshu
On Thu, Jun 4, 2026 at 4:22 PM Anshu Kumari
This series adds a --dhcpv6-opt CODE,VALUE command-line option to inject custom options into DHCPv6 replies, complementing the existing --dhcp-opt support for DHCPv4.
The primary use case is UEFI HTTP Boot, which requires Vendor Class (option 16) with the correct enterprise-number + length-prefixed wire encoding per RFC 8415 Section 21.16, and Boot File URL (option 59).
Value formats are determined automatically from the option code via a type table. Supported types include plain strings, IPv6 addresses (single and list), 8/16/32-bit integers, vendor class (ENTERPRISE:DATA), and length-prefixed string lists.
Patch 1 adds the CLI flag, storage, and basic man page entry. Patch 2 adds the type table and binary parser for all supported types. Patch 3 injects the parsed options into DHCPv6 reply packets.
Anshu Kumari (3): conf: Add --dhcpv6-opt command-line option dhcpv6: Add option type table and value parser dhcpv6: Inject custom options into DHCPv6 replies
conf.c | 26 ++++- dhcpv6.c | 295 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ dhcpv6.h | 1 + passt.1 | 30 ++++++ passt.h | 16 +++ 5 files changed, 367 insertions(+), 1 deletion(-)
-- 2.54.0