upstream: load_hostkeys()/hostkeys_foreach() variants for FILE*

Add load_hostkeys_file() and hostkeys_foreach_file() that accept a
FILE* argument instead of opening the file directly.

Original load_hostkeys() and hostkeys_foreach() are implemented using
these new interfaces.

Add a u_int note field to the hostkey_entry and hostkey_foreach_line
structs that is passed directly from the load_hostkeys() and
hostkeys_foreach() call. This is a lightweight way to annotate results
between different invocations of load_hostkeys().

ok markus@

OpenBSD-Commit-ID: 6ff6db13ec9ee4edfa658b2c38baad0f505d8c20

1 files changed, 43 insertions, 11 deletions

diff --git a/hostfile.c b/hostfile.c
index 4ec7b671..c3a28178 100644
--- a/hostfile.c
+++ b/hostfile.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: hostfile.c,v 1.86 2020/10/18 11:32:01 djm Exp $ */
+/* $OpenBSD: hostfile.c,v 1.87 2020/12/20 23:36:51 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -260,6 +260,7 @@ record_hostkey(struct hostkey_foreach_line *l, void *_ctx)
 	hostkeys->entries[hostkeys->num_entries].key = l->key;
 	l->key = NULL; /* steal it */
 	hostkeys->entries[hostkeys->num_entries].marker = l->marker;
+	hostkeys->entries[hostkeys->num_entries].note = l->note;
 	hostkeys->num_entries++;
 	ctx->num_loaded++;
 
@@ -267,7 +268,8 @@ record_hostkey(struct hostkey_foreach_line *l, void *_ctx)
 }
 
 void
-load_hostkeys(struct hostkeys *hostkeys, const char *host, const char *path)
+load_hostkeys_file(struct hostkeys *hostkeys, const char *host,
+    const char *path, FILE *f, u_int note)
 {
 	int r;
 	struct load_callback_ctx ctx;
@@ -276,8 +278,8 @@ load_hostkeys(struct hostkeys *hostkeys, const char *host, const char *path)
 	ctx.num_loaded = 0;
 	ctx.hostkeys = hostkeys;
 
-	if ((r = hostkeys_foreach(path, record_hostkey, &ctx, host, NULL,
-	    HKF_WANT_MATCH|HKF_WANT_PARSE_KEY)) != 0) {
+	if ((r = hostkeys_foreach_file(path, f, record_hostkey, &ctx, host,
+	    NULL, HKF_WANT_MATCH|HKF_WANT_PARSE_KEY, note)) != 0) {
 		if (r != SSH_ERR_SYSTEM_ERROR && errno != ENOENT)
 			debug_fr(r, "hostkeys_foreach failed for %s", path);
 	}
@@ -286,6 +288,21 @@ load_hostkeys(struct hostkeys *hostkeys, const char *host, const char *path)
 }
 
 void
+load_hostkeys(struct hostkeys *hostkeys, const char *host, const char *path,
+    u_int note)
+{
+	FILE *f;
+
+	if ((f = fopen(path, "r")) == NULL) {
+		debug_f("fopen %s: %s", path, strerror(errno));
+		return;
+	}
+
+	load_hostkeys_file(hostkeys, host, path, f, note);
+	fclose(f);
+}
+
+void
 free_hostkeys(struct hostkeys *hostkeys)
 {
 	u_int i;
@@ -620,7 +637,7 @@ hostfile_replace_entries(const char *filename, const char *host, const char *ip,
 
 	/* Remove stale/mismatching entries for the specified host */
 	if ((r = hostkeys_foreach(filename, host_delete, &ctx, host, ip,
-	    HKF_WANT_PARSE_KEY)) != 0) {
+	    HKF_WANT_PARSE_KEY, 0)) != 0) {
 		oerrno = errno;
 		error_fr(r, "hostkeys_foreach");
 		goto fail;
@@ -733,10 +750,9 @@ match_maybe_hashed(const char *host, const char *names, int *was_hashed)
 }
 
 int
-hostkeys_foreach(const char *path, hostkeys_foreach_fn *callback, void *ctx,
-    const char *host, const char *ip, u_int options)
+hostkeys_foreach_file(const char *path, FILE *f, hostkeys_foreach_fn *callback,
+    void *ctx, const char *host, const char *ip, u_int options, u_int note)
 {
-	FILE *f;
 	char *line = NULL, ktype[128];
 	u_long linenum = 0;
 	char *cp, *cp2;
@@ -749,10 +765,7 @@ hostkeys_foreach(const char *path, hostkeys_foreach_fn *callback, void *ctx,
 	memset(&lineinfo, 0, sizeof(lineinfo));
 	if (host == NULL && (options & HKF_WANT_MATCH) != 0)
 		return SSH_ERR_INVALID_ARGUMENT;
-	if ((f = fopen(path, "r")) == NULL)
-		return SSH_ERR_SYSTEM_ERROR;
 
-	debug3_f("reading file \"%s\"", path);
 	while (getline(&line, &linesize, f) != -1) {
 		linenum++;
 		line[strcspn(line, "\n")] = '\0';
@@ -766,6 +779,7 @@ hostkeys_foreach(const char *path, hostkeys_foreach_fn *callback, void *ctx,
 		lineinfo.marker = MRK_NONE;
 		lineinfo.status = HKF_STATUS_OK;
 		lineinfo.keytype = KEY_UNSPEC;
+		lineinfo.note = note;
 
 		/* Skip any leading whitespace, comments and empty lines. */
 		for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
@@ -902,6 +916,24 @@ hostkeys_foreach(const char *path, hostkeys_foreach_fn *callback, void *ctx,
 	sshkey_free(lineinfo.key);
 	free(lineinfo.line);
 	free(line);
+	return r;
+}
+
+int
+hostkeys_foreach(const char *path, hostkeys_foreach_fn *callback, void *ctx,
+    const char *host, const char *ip, u_int options, u_int note)
+{
+	FILE *f;
+	int r, oerrno;
+
+	if ((f = fopen(path, "r")) == NULL)
+		return SSH_ERR_SYSTEM_ERROR;
+
+	debug3_f("reading file \"%s\"", path);
+	r = hostkeys_foreach_file(path, f, callback, ctx, host, ip,
+	    options, note);
+	oerrno = errno;
 	fclose(f);
+	errno = oerrno;
 	return r;
 }