From 0c60a44551d28fc04d65b42d06ccb8cbdeb0ea6c Mon Sep 17 00:00:00 2001
From: job <job@openbsd.org>
Date: Mon, 11 Dec 2023 15:50:23 +0000
Subject: [PATCH] Log a warning when a manifest replay is detected

OK tb@ claudio@
---
 usr.sbin/rpki-client/mft.c    | 14 +++++++++-----
 usr.sbin/rpki-client/parser.c | 11 ++++++++---
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/usr.sbin/rpki-client/mft.c b/usr.sbin/rpki-client/mft.c
index 0e4af6e1fdc..8fd3755f1c9 100644
--- a/usr.sbin/rpki-client/mft.c
+++ b/usr.sbin/rpki-client/mft.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mft.c,v 1.99 2023/10/13 12:06:49 job Exp $ */
+/*	$OpenBSD: mft.c,v 1.100 2023/12/11 15:50:23 job Exp $ */
 /*
  * Copyright (c) 2022 Theo Buehler <tb@openbsd.org>
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -545,8 +545,9 @@ mft_read(struct ibuf *b)
 }
 
 /*
- * Compare two MFT files, returns 1 if first MFT is preferred and 0 if second
- * MFT should be used.
+ * Compare the manifestNumber of two MFT files.
+ * Returns 1 if first MFT should be used, 0 if both are equal, and -1 if the
+ * second MFT should be used.
  */
 int
 mft_compare(const struct mft *a, const struct mft *b)
@@ -556,16 +557,19 @@ mft_compare(const struct mft *a, const struct mft *b)
 	if (b == NULL)
 		return 1;
 	if (a == NULL)
-		return 0;
+		return -1;
 
 	r = strlen(a->seqnum) - strlen(b->seqnum);
 	if (r > 0)	/* seqnum in a is longer -> higher */
 		return 1;
 	if (r < 0)	/* seqnum in a is shorter -> smaller */
-		return 0;
+		return -1;
 
 	r = strcmp(a->seqnum, b->seqnum);
 	if (r > 0)	/* a is greater, prefer a */
 		return 1;
+	if (r < 0)	/* b is greater, prefer b */
+		return -1;
+
 	return 0;
 }
diff --git a/usr.sbin/rpki-client/parser.c b/usr.sbin/rpki-client/parser.c
index 61a66db01c4..04259848e13 100644
--- a/usr.sbin/rpki-client/parser.c
+++ b/usr.sbin/rpki-client/parser.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: parser.c,v 1.101 2023/12/09 00:44:18 job Exp $ */
+/*	$OpenBSD: parser.c,v 1.102 2023/12/11 15:50:23 job Exp $ */
 /*
  * Copyright (c) 2019 Claudio Jeker <claudio@openbsd.org>
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -361,7 +361,7 @@ proc_parser_mft(struct entity *entp, struct mft **mp, char **crlfile,
 	struct crl	*crl, *crl1, *crl2;
 	char		*file, *file1, *file2, *crl1file, *crl2file;
 	const char	*err1, *err2;
-	int		 warned = 0;
+	int		 r, warned = 0;
 
 	*mp = NULL;
 	*crlmtime = 0;
@@ -376,7 +376,12 @@ proc_parser_mft(struct entity *entp, struct mft **mp, char **crlfile,
 		if (err2 != NULL)
 			err1 = err2;
 
-	if (mft_compare(mft1, mft2) == 1) {
+	r = mft_compare(mft1, mft2);
+	if (r == -1 && mft1 != NULL && mft2 != NULL)
+		warnx("%s: manifest replay detected (expected >= #%s, got #%s)",
+		    file1, mft2->seqnum, mft1->seqnum);
+
+	if (r == 1) {
 		*mp = proc_parser_mft_post(file1, mft1, entp->path, err1,
 		    &warned);
 		if (*mp == NULL) {
-- 
2.20.1