From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate001.proxmox.com (gate001.proxmox.com [45.144.208.40]) by lore.proxmox.com (Postfix) with ESMTPS id 458831FF0AA for ; Tue, 20 Oct 2026 10:24:50 +0200 (CEST) Received: from gate001.proxmox.com (localhost.localdomain [127.0.0.1]) by gate001.proxmox.com (Proxmox) with ESMTP id 2F0A82162D; Tue, 20 Oct 2026 10:24:48 +0200 (CEST) From: David Riley To: pve-devel@lists.proxmox.com Subject: [PATCH pve-common v2 1/2] certificate: add helpers for lifetime-based ACME renewal Date: Tue, 20 Oct 2026 10:24:14 +0200 Message-ID: <20261020082415.35215-2-d.riley@proxmox.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261020082415.35215-1-d.riley@proxmox.com> References: <20261020082415.35215-1-d.riley@proxmox.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1792484682816 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.717 Adjusted score from AWL reputation of From: address DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment (newer systems) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: IDZCGZOHSMIR4AV5UT4TISFZZTEUEAVG X-Message-ID-Hash: IDZCGZOHSMIR4AV5UT4TISFZZTEUEAVG X-MailFrom: d.riley@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: David Riley X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox VE development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Add helpers to calculate a renewal lead time based on the actual lifetime of an X.509 certificate. Previously, certificate renewals relied on a hardcoded threshold. To prepare for dynamic thresholds (#8006), introduce calculations that scale the renewal lead time proportionally to the certificate's validity period. The scaling mirrors the logic already used in Proxmox Backup Server [1]: certificates living for less than 10 days are renewed once 1/2 of their lifetime has elapsed, while longer-lived certificates are renewed once 2/3 has elapsed [2]. A 3-day minimum floor is present to ensure the daily update service has multiple chances to retry transient failures. Link: https://bugzilla.proxmox.com/show_bug.cgi?id=8006 [1] https://lore.proxmox.com/pbs-devel/20260423134607.105229-2-m.federanko@proxmox.com/ [2] https://letsencrypt.org/docs/integration-guide/#when-to-renew Signed-off-by: David Riley --- src/PVE/Certificate.pm | 39 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 37 insertions(+), 2 deletions(-) diff --git a/src/PVE/Certificate.pm b/src/PVE/Certificate.pm index b8415e2..d2d0847 100644 --- a/src/PVE/Certificate.pm +++ b/src/PVE/Certificate.pm @@ -5,6 +5,7 @@ use warnings; use Date::Parse; use Encode qw(decode encode); +use List::Util qw(max); use MIME::Base64 qw(decode_base64 encode_base64); use Net::SSLeay; @@ -331,16 +332,28 @@ sub get_certificate_info { # Obtain the expiration timestamp of a X.509 certificate as a UNIX epoch. sub get_expiration_as_epoch { my ($cert_path) = @_; + my (undef, $not_after) = get_validity_as_epoch($cert_path); + return $not_after; +} + +# Obtain the notBefore and notAfter timestamps of a X.509 certificate as UNIX epochs. +sub get_validity_as_epoch { + my ($cert_path) = @_; my $cert = $read_certificate->($cert_path); - my $not_after = eval { convert_asn1_to_epoch(Net::SSLeay::X509_get_notAfter($cert)) }; + my ($not_before, $not_after) = eval { + ( + convert_asn1_to_epoch(Net::SSLeay::X509_get_notBefore($cert)), + convert_asn1_to_epoch(Net::SSLeay::X509_get_notAfter($cert)), + ); + }; my $err = $@; Net::SSLeay::X509_free($cert); die $err if $err; - return $not_after; + return ($not_before, $not_after); } # Checks whether certificate expires before $timestamp (UNIX epoch) @@ -354,6 +367,28 @@ sub check_expiry { return ($not_after < $timestamp) ? 1 : 0; } +# Long-lived certs are renewed once 2/3 of their lifetime has elapsed; short-lived ones (under +# ten days) already at 1/2, following Let's Encrypt's integration guide. A 3-day floor still +# applies so the daily-update service has a couple of chances to retry transient failures. +sub get_cert_renew_lead_time { + my ($cert_path) = @_; + + my ($not_before, $not_after) = get_validity_as_epoch($cert_path); + my $lifetime = $not_after - $not_before; + + if ($lifetime <= 0) { + warn "Unexpected validity period ($lifetime s) for '$cert_path', falling back to a 30 day" + . " renewal lead time\n"; + + return 30 * 24 * 60 * 60; + } + + my $scale = $lifetime < (10 * 24 * 60 * 60) ? 2 : 3; + my $lead = int($lifetime / $scale); + + return max($lead, 3 * 24 * 60 * 60); # 3 day minimum +} + # Create a CSR and certificate key for a given order # returns path to CSR file or path to CSR and key files sub generate_csr { -- 2.47.3