From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by passt.top (Postfix, from userid 1000) id 4BEFE5A0627; Sun, 03 May 2026 23:56:01 +0200 (CEST) From: Stefano Brivio To: passt-dev@passt.top Subject: [PATCH v6 17/18] conf, fwd: Allow switching to new rules received from pesto Date: Sun, 3 May 2026 23:56:00 +0200 Message-ID: <20260503215601.823029-18-sbrivio@redhat.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260503215601.823029-1-sbrivio@redhat.com> References: <20260503215601.823029-1-sbrivio@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: CJHQ6UE3CG2IEA4UZ4BODHQIKI3CAHQW X-Message-ID-Hash: CJHQ6UE3CG2IEA4UZ4BODHQIKI3CAHQW X-MailFrom: sbrivio@passt.top X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Jon Maloy , David Gibson , Laurent Vivier X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: From: David Gibson We can now receive updates to the forwarding rules from the pesto client and store them in a "pending" copy of the forwarding tables. Implement switching to using the new rules. The logic is in a new fwd_listen_switch(). For now this closes all listening sockets related to the old tables, swaps the active and pending tables, then listens based on the new tables. In future we look to improve this so that we don't temporarily stop listening on ports that both the old and new tables specify. Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- conf.c | 5 ++--- fwd.c | 34 ++++++++++++++++++++++++++++++++++ fwd.h | 1 + 3 files changed, 37 insertions(+), 3 deletions(-) diff --git a/conf.c b/conf.c index f035fd3..75b8291 100644 --- a/conf.c +++ b/conf.c @@ -2159,15 +2159,14 @@ void conf_handler(struct ctx *c, uint32_t events) fwd_rules_dump(info, fwd->rules, fwd->count, " ", ""); } + + fwd_listen_switch(c); } if (events & EPOLLHUP) { debug("Configuration client hangup"); - goto close; } - return; - close: conf_close(c); diff --git a/fwd.c b/fwd.c index d93d2e5..35b9e2b 100644 --- a/fwd.c +++ b/fwd.c @@ -534,6 +534,40 @@ int fwd_listen_init(const struct ctx *c) return 0; } +/** + * fwd_listen_switch() - Switch from current to pending rules table + * @c: Execution context + */ +void fwd_listen_switch(struct ctx *c) +{ + struct fwd_table *tmp[PIF_NUM_TYPES]; + unsigned i; + + /* Stop listening on the old tables */ + for (i = 0; i < PIF_NUM_TYPES; i++) { + struct fwd_table *fwd = c->fwd[i]; + + if (!fwd) + continue; + + debug("Flushing %u old %s rules", fwd->count, pif_name(i)); + fwd_listen_close(fwd); + fwd->count = fwd->sock_count = 0; + } + + /* Swap active and pending tables */ + static_assert(sizeof(tmp) == sizeof(c->fwd) && + sizeof(tmp) == sizeof(c->fwd_pending), + "Temporary has wrong size"); + memcpy(&tmp, (void *)c->fwd, sizeof(tmp)); + memcpy((void *)c->fwd, (void *)c->fwd_pending, sizeof(tmp)); + memcpy((void *)c->fwd_pending, &tmp, sizeof(tmp)); + + /* Start listening on the new tables */ + if (fwd_listen_init(c) < 0) + err("Error switching to new forwarding rules"); +} + /* See enum in kernel's include/net/tcp_states.h */ #define UDP_LISTEN 0x07 #define TCP_LISTEN 0x0a diff --git a/fwd.h b/fwd.h index ac24782..b60697d 100644 --- a/fwd.h +++ b/fwd.h @@ -61,6 +61,7 @@ int fwd_listen_sync(const struct ctx *c, uint8_t pif, const struct fwd_scan *tcp, const struct fwd_scan *udp); void fwd_listen_close(const struct fwd_table *fwd); int fwd_listen_init(const struct ctx *c); +void fwd_listen_switch(struct ctx *c); bool nat_inbound(const struct ctx *c, const union inany_addr *addr, union inany_addr *translated); -- 2.43.0