Factor out the SHA256 hash checks into valid_filehash() so that it can

be used by the RRDP code as well.
OK tb@

3 files changed, 50 insertions, 46 deletions

diff --git a/usr.sbin/rpki-client/extern.h b/usr.sbin/rpki-client/extern.h
index fa862a6ce7a..4a77b431b75 100644
--- a/usr.sbin/rpki-client/extern.h
+++ b/usr.sbin/rpki-client/extern.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: extern.h,v 1.51 2021/03/05 12:33:19 claudio Exp $ */
+/*	$OpenBSD: extern.h,v 1.52 2021/03/05 16:00:00 claudio Exp $ */
 /*
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -354,6 +354,7 @@ int		 valid_ta(const char *, struct auth_tree *,
 int		 valid_cert(const char *, struct auth_tree *,
 		    const struct cert *);
 int		 valid_roa(const char *, struct auth_tree *, struct roa *);
+int		 valid_filehash(const char *, const char *, size_t);
 
 /* Working with CMS files. */
 
diff --git a/usr.sbin/rpki-client/mft.c b/usr.sbin/rpki-client/mft.c
index 04944b79369..992adf02fa6 100644
--- a/usr.sbin/rpki-client/mft.c
+++ b/usr.sbin/rpki-client/mft.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mft.c,v 1.28 2021/03/04 14:24:17 claudio Exp $ */
+/*	$OpenBSD: mft.c,v 1.29 2021/03/05 16:00:00 claudio Exp $ */
 /*
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -434,62 +434,33 @@ out:
 }
 
 /*
- * Check the hash value of a file.
+ * Check all files and their hashes in a MFT structure.
  * Return zero on failure, non-zero on success.
  */
-static int
-mft_validfilehash(const char *fn, const struct mftfile *m)
+int
+mft_check(const char *fn, struct mft *p)
 {
-	char	filehash[SHA256_DIGEST_LENGTH];
-	char	buffer[8192];
+	size_t	i;
+	int	rc = 1;
 	char	*cp, *path = NULL;
-	SHA256_CTX ctx;
-	ssize_t	nr;
-	int	fd;
 
 	/* Check hash of file now, but first build path for it */
 	cp = strrchr(fn, '/');
 	assert(cp != NULL);
 	assert(cp - fn < INT_MAX);
-	if (asprintf(&path, "%.*s/%s", (int)(cp - fn), fn, m->file) == -1)
-		err(1, NULL);
 
-	if ((fd = open(path, O_RDONLY)) == -1) {
-		warn("%s: referenced file %s", fn, m->file);
+	for (i = 0; i < p->filesz; i++) {
+		const struct mftfile *m = &p->files[i];
+		if (asprintf(&path, "%.*s/%s", (int)(cp - fn), fn,
+		    m->file) == -1)
+			err(1, NULL);
+		if (!valid_filehash(path, m->hash, sizeof(m->hash))) {
+			warnx("%s: bad message digest for %s", fn, m->file);
+			rc = 0;
+		}
 		free(path);
-		return 0;
-	}
-	free(path);
-
-	SHA256_Init(&ctx);
-	while ((nr = read(fd, buffer, sizeof(buffer))) > 0) {
-		SHA256_Update(&ctx, buffer, nr);
-	}
-	close(fd);
-
-	SHA256_Final(filehash, &ctx);
-	if (memcmp(m->hash, filehash, SHA256_DIGEST_LENGTH) != 0) {
-		warnx("%s: bad message digest for %s", fn, m->file);
-		return 0;
 	}
 
-	return 1;
-}
-
-/*
- * Check all files and their hashes in a MFT structure.
- * Return zero on failure, non-zero on success.
- */
-int
-mft_check(const char *fn, struct mft *p)
-{
-	size_t	i;
-	int	rc = 1;
-
-	for (i = 0; i < p->filesz; i++)
-		if (!mft_validfilehash(fn, &p->files[i]))
-			rc = 0;
-
 	return rc;
 }
 
diff --git a/usr.sbin/rpki-client/validate.c b/usr.sbin/rpki-client/validate.c
index 88a9c6bb827..39779a3e6f2 100644
--- a/usr.sbin/rpki-client/validate.c
+++ b/usr.sbin/rpki-client/validate.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: validate.c,v 1.11 2020/09/12 15:46:48 claudio Exp $ */
+/*	$OpenBSD: validate.c,v 1.12 2021/03/05 16:00:00 claudio Exp $ */
 /*
  * Copyright (c) 2019 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -20,6 +20,7 @@
 #include <arpa/inet.h>
 #include <assert.h>
 #include <err.h>
+#include <fcntl.h>
 #include <inttypes.h>
 #include <stdarg.h>
 #include <stdlib.h>
@@ -240,3 +241,34 @@ valid_roa(const char *fn, struct auth_tree *auths, struct roa *roa)
 
 	return 1;
 }
+
+/*
+ * Validate a file by verifying the SHA256 hash of that file.
+ * Returns 1 if valid, 0 otherwise.
+ */
+int
+valid_filehash(const char *fn, const char *hash, size_t hlen)
+{
+	SHA256_CTX ctx;
+	char	filehash[SHA256_DIGEST_LENGTH];
+	char	buffer[8192];
+	ssize_t	nr;
+	int	fd;
+
+	if (hlen != sizeof(filehash))
+		errx(1, "bad hash size");
+
+	if ((fd = open(fn, O_RDONLY)) == -1)
+		return 0;
+
+	SHA256_Init(&ctx);
+	while ((nr = read(fd, buffer, sizeof(buffer))) > 0)
+		SHA256_Update(&ctx, buffer, nr);
+	close(fd);
+
+	SHA256_Final(filehash, &ctx);
+	if (memcmp(hash, filehash, sizeof(filehash)) != 0)
+		return 0;
+
+	return 1;
+}