On Tue, Aug 05, 2025 at 05:46:22PM +0200, Laurent Vivier wrote:
This patch refactors the dhcpv6() function to accept `struct iov_tail *data` directly as its packet input, replacing the `const struct pool *p` parameter. Consequently, dhcpv6() no longer fetches packet data internally using packet_data().
This change simplifies callers, such as tap6_handler(), which now pass the iov_tail representing the L4 UDP segment (DHCPv6 message) directly. This removes the need for intermediate packet pool handling.
Signed-off-by: Laurent Vivier
Reviewed-by: David Gibson
--- dhcpv6.c | 29 +++++++++++++---------------- dhcpv6.h | 2 +- tap.c | 6 ++---- 3 files changed, 16 insertions(+), 21 deletions(-)
diff --git a/dhcpv6.c b/dhcpv6.c index f54a75c642df..52611d742b0b 100644 --- a/dhcpv6.c +++ b/dhcpv6.c @@ -539,19 +539,19 @@ static size_t dhcpv6_client_fqdn_fill(const struct iov_tail *data, /** * dhcpv6() - Check if this is a DHCPv6 message, reply as needed * @c: Execution context - * @p: Packet pool, single packet starting from UDP header + * @data: Single packet starting from UDP header * @saddr: Source IPv6 address of original message * @daddr: Destination IPv6 address of original message * * Return: 0 if it's not a DHCPv6 message, 1 if handled, -1 on failure */ -int dhcpv6(struct ctx *c, const struct pool *p, +int dhcpv6(struct ctx *c, struct iov_tail *data, const struct in6_addr *saddr, const struct in6_addr *daddr) { const struct opt_server_id *server_id = NULL; - struct iov_tail data, opt, client_id_base; const struct opt_hdr *client_id = NULL; struct opt_server_id server_id_storage; + struct iov_tail opt, client_id_base; const struct opt_ia_na *ia = NULL; struct opt_hdr client_id_storage; struct opt_ia_na ia_storage; @@ -562,10 +562,7 @@ int dhcpv6(struct ctx *c, const struct pool *p, const struct udphdr *uh; size_t mlen, n;
- if (!packet_get(p, 0, &data)) - return -1; - - uh = IOV_REMOVE_HEADER(&data, uh_storage); + uh = IOV_REMOVE_HEADER(data, uh_storage); if (!uh) return -1;
@@ -578,7 +575,7 @@ int dhcpv6(struct ctx *c, const struct pool *p, if (!IN6_IS_ADDR_MULTICAST(daddr)) return -1;
- mlen = iov_tail_size(&data); + mlen = iov_tail_size(data); if (mlen + sizeof(*uh) != ntohs(uh->len) || mlen < sizeof(*mh)) return -1;
@@ -586,23 +583,23 @@ int dhcpv6(struct ctx *c, const struct pool *p,
src = &c->ip6.our_tap_ll;
- mh = IOV_REMOVE_HEADER(&data, mh_storage); + mh = IOV_REMOVE_HEADER(data, mh_storage); if (!mh) return -1;
- client_id_base = data; + client_id_base = *data; if (dhcpv6_opt(&client_id_base, OPT_CLIENTID)) client_id = IOV_PEEK_HEADER(&client_id_base, client_id_storage); if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id)) return -1;
- opt = data; + opt = *data; if (dhcpv6_opt(&opt, OPT_SERVERID)) server_id = IOV_PEEK_HEADER(&opt, server_id_storage); if (server_id && ntohs(server_id->hdr.l) != OPT_VSIZE(server_id)) return -1;
- opt = data; + opt = *data; if (dhcpv6_opt(&opt, OPT_IA_NA)) ia = IOV_PEEK_HEADER(&opt, ia_storage); if (ia && ntohs(ia->hdr.l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta))) @@ -620,9 +617,9 @@ int dhcpv6(struct ctx *c, const struct pool *p, if (mh->type == TYPE_CONFIRM && server_id) return -1;
- if (dhcpv6_ia_notonlink(&data, &c->ip6.addr)) { + if (dhcpv6_ia_notonlink(data, &c->ip6.addr)) {
- dhcpv6_send_ia_notonlink(c, &data, &client_id_base, + dhcpv6_send_ia_notonlink(c, data, &client_id_base, ntohs(client_id->l), mh->xid);
return 1; @@ -635,7 +632,7 @@ int dhcpv6(struct ctx *c, const struct pool *p, memcmp(&resp.server_id, server_id, sizeof(resp.server_id))) return -1;
- if (ia || dhcpv6_opt(&data, OPT_IA_TA)) + if (ia || dhcpv6_opt(data, OPT_IA_TA)) return -1;
info("DHCPv6: received INFORMATION_REQUEST, sending REPLY"); @@ -668,7 +665,7 @@ int dhcpv6(struct ctx *c, const struct pool *p, n = offsetof(struct resp_t, client_id) + sizeof(struct opt_hdr) + ntohs(client_id->l); n = dhcpv6_dns_fill(c, (char *)&resp, n); - n = dhcpv6_client_fqdn_fill(&data, c, (char *)&resp, n); + n = dhcpv6_client_fqdn_fill(data, c, (char *)&resp, n);
resp.hdr.xid = mh->xid;
diff --git a/dhcpv6.h b/dhcpv6.h index 580998862227..c706dfdbb2ac 100644 --- a/dhcpv6.h +++ b/dhcpv6.h @@ -6,7 +6,7 @@ #ifndef DHCPV6_H #define DHCPV6_H
-int dhcpv6(struct ctx *c, const struct pool *p, +int dhcpv6(struct ctx *c, struct iov_tail *data, struct in6_addr *saddr, struct in6_addr *daddr); void dhcpv6_init(const struct ctx *c);
diff --git a/tap.c b/tap.c index 7d7e89304723..3262b44c4287 100644 --- a/tap.c +++ b/tap.c @@ -975,11 +975,9 @@ resume: continue;
if (proto == IPPROTO_UDP) { - PACKET_POOL_P(pkt, 1, in->buf, in->buf_size); - - packet_add(pkt, &data); + struct iov_tail uh_data = data;
- if (dhcpv6(c, pkt, saddr, daddr)) + if (dhcpv6(c, &uh_data, saddr, daddr)) continue; }
-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson