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 bf22d63e8..20b66d9bd 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;