1 /* $OpenBSD: sshbuf-io.c,v 1.2 2020/01/25 23:28:06 djm Exp $ */
2 /*
3 * Copyright (c) 2011 Damien Miller
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include "includes.h"
19
20 #include <sys/types.h>
21 #include <sys/stat.h>
22
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <unistd.h>
26 #include <string.h>
27
28 #include "ssherr.h"
29 #include "sshbuf.h"
30 #include "atomicio.h"
31
32 /* Load a file from a fd into a buffer */
33 int
sshbuf_load_fd(int fd,struct sshbuf ** blobp)34 sshbuf_load_fd(int fd, struct sshbuf **blobp)
35 {
36 u_char buf[4096];
37 size_t len;
38 struct stat st;
39 int r;
40 struct sshbuf *blob;
41
42 *blobp = NULL;
43
44 if (fstat(fd, &st) == -1)
45 return SSH_ERR_SYSTEM_ERROR;
46 if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
47 st.st_size > SSHBUF_SIZE_MAX)
48 return SSH_ERR_INVALID_FORMAT;
49 if ((blob = sshbuf_new()) == NULL)
50 return SSH_ERR_ALLOC_FAIL;
51 for (;;) {
52 if ((len = atomicio(read, fd, buf, sizeof(buf))) == 0) {
53 if (errno == EPIPE)
54 break;
55 r = SSH_ERR_SYSTEM_ERROR;
56 goto out;
57 }
58 if ((r = sshbuf_put(blob, buf, len)) != 0)
59 goto out;
60 if (sshbuf_len(blob) > SSHBUF_SIZE_MAX) {
61 r = SSH_ERR_INVALID_FORMAT;
62 goto out;
63 }
64 }
65 if ((st.st_mode & (S_IFSOCK|S_IFCHR|S_IFIFO)) == 0 &&
66 st.st_size != (off_t)sshbuf_len(blob)) {
67 r = SSH_ERR_FILE_CHANGED;
68 goto out;
69 }
70 /* success */
71 *blobp = blob;
72 blob = NULL; /* transferred */
73 r = 0;
74 out:
75 explicit_bzero(buf, sizeof(buf));
76 sshbuf_free(blob);
77 return r;
78 }
79
80 int
sshbuf_load_file(const char * path,struct sshbuf ** bufp)81 sshbuf_load_file(const char *path, struct sshbuf **bufp)
82 {
83 int r, fd, oerrno;
84
85 *bufp = NULL;
86 if ((fd = open(path, O_RDONLY)) == -1)
87 return SSH_ERR_SYSTEM_ERROR;
88 if ((r = sshbuf_load_fd(fd, bufp)) != 0)
89 goto out;
90 /* success */
91 r = 0;
92 out:
93 oerrno = errno;
94 close(fd);
95 if (r != 0)
96 errno = oerrno;
97 return r;
98 }
99
100 int
sshbuf_write_file(const char * path,struct sshbuf * buf)101 sshbuf_write_file(const char *path, struct sshbuf *buf)
102 {
103 int fd, oerrno;
104
105 if ((fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644)) == -1)
106 return SSH_ERR_SYSTEM_ERROR;
107 if (atomicio(vwrite, fd, sshbuf_mutable_ptr(buf),
108 sshbuf_len(buf)) != sshbuf_len(buf) || close(fd) != 0) {
109 oerrno = errno;
110 close(fd);
111 unlink(path);
112 errno = oerrno;
113 return SSH_ERR_SYSTEM_ERROR;
114 }
115 return 0;
116 }
117
118