upstream: factor out reading/writing sshbufs to dedicated

functions; feedback and ok markus@

OpenBSD-Commit-ID: dc09e5f1950b7acc91b8fdf8015347782d2ecd3d

1 files changed, 9 insertions, 68 deletions

diff --git a/authfile.c b/authfile.c
index bf22d63e..20b66d9b 100644
--- a/authfile.c
+++ b/authfile.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: authfile.c,v 1.136 2020/01/02 22:38:33 djm Exp $ */
+/* $OpenBSD: authfile.c,v 1.137 2020/01/25 23:02:13 djm Exp $ */
 /*
  * Copyright (c) 2000, 2013 Markus Friedl.  All rights reserved.
  *
@@ -55,20 +55,13 @@
 static int
 sshkey_save_private_blob(struct sshbuf *keybuf, const char *filename)
 {
-	int fd, oerrno;
+	int r;
+	mode_t omask;
 
-	if ((fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0600)) == -1)
-		return SSH_ERR_SYSTEM_ERROR;
-	if (atomicio(vwrite, fd, sshbuf_mutable_ptr(keybuf),
-	    sshbuf_len(keybuf)) != sshbuf_len(keybuf)) {
-		oerrno = errno;
-		close(fd);
-		unlink(filename);
-		errno = oerrno;
-		return SSH_ERR_SYSTEM_ERROR;
-	}
-	close(fd);
-	return 0;
+	omask = umask(077);
+	r = sshbuf_write_file(filename, keybuf);
+	umask(omask);
+	return r;
 }
 
 int
@@ -92,49 +85,6 @@ sshkey_save_private(struct sshkey *key, const char *filename,
 	return r;
 }
 
-/* Load a key from a fd into a buffer */
-int
-sshkey_load_file(int fd, struct sshbuf *blob)
-{
-	u_char buf[1024];
-	size_t len;
-	struct stat st;
-	int r;
-
-	if (fstat(fd, &st) == -1)
-		return SSH_ERR_SYSTEM_ERROR;
-	if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
-	    st.st_size > MAX_KEY_FILE_SIZE)
-		return SSH_ERR_INVALID_FORMAT;
-	for (;;) {
-		if ((len = atomicio(read, fd, buf, sizeof(buf))) == 0) {
-			if (errno == EPIPE)
-				break;
-			r = SSH_ERR_SYSTEM_ERROR;
-			goto out;
-		}
-		if ((r = sshbuf_put(blob, buf, len)) != 0)
-			goto out;
-		if (sshbuf_len(blob) > MAX_KEY_FILE_SIZE) {
-			r = SSH_ERR_INVALID_FORMAT;
-			goto out;
-		}
-	}
-	if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
-	    st.st_size != (off_t)sshbuf_len(blob)) {
-		r = SSH_ERR_FILE_CHANGED;
-		goto out;
-	}
-	r = 0;
-
- out:
-	explicit_bzero(buf, sizeof(buf));
-	if (r != 0)
-		sshbuf_reset(blob);
-	return r;
-}
-
-
 /* XXX remove error() calls from here? */
 int
 sshkey_perm_ok(int fd, const char *filename)
@@ -199,11 +149,7 @@ sshkey_load_private_type_fd(int fd, int type, const char *passphrase,
 
 	if (keyp != NULL)
 		*keyp = NULL;
-	if ((buffer = sshbuf_new()) == NULL) {
-		r = SSH_ERR_ALLOC_FAIL;
-		goto out;
-	}
-	if ((r = sshkey_load_file(fd, buffer)) != 0 ||
+	if ((r = sshbuf_load_fd(fd, &buffer)) != 0 ||
 	    (r = sshkey_parse_private_fileblob_type(buffer, type,
 	    passphrase, keyp, commentp)) != 0)
 		goto out;
@@ -234,12 +180,7 @@ sshkey_load_private(const char *filename, const char *passphrase,
 		r = SSH_ERR_KEY_BAD_PERMISSIONS;
 		goto out;
 	}
-
-	if ((buffer = sshbuf_new()) == NULL) {
-		r = SSH_ERR_ALLOC_FAIL;
-		goto out;
-	}
-	if ((r = sshkey_load_file(fd, buffer)) != 0 ||
+	if ((r = sshbuf_load_fd(fd, &buffer)) != 0 ||
 	    (r = sshkey_parse_private_fileblob(buffer, passphrase, keyp,
 	    commentp)) != 0)
 		goto out;