upstream: Add a sshbuf_read() that attempts to read(2) directly in

to a sshbuf; ok markus@

OpenBSD-Commit-ID: 2d8f249040a4279f3bc23c018947384de8d4a45b
This commit is contained in:
djm@openbsd.org 2022-01-22 00:43:43 +00:00 committed by Damien Miller
parent c7964fb982
commit 754e0d5c77
2 changed files with 43 additions and 2 deletions

View File

@ -1,4 +1,4 @@
/* $OpenBSD: sshbuf-misc.c,v 1.17 2021/08/11 05:21:32 djm Exp $ */
/* $OpenBSD: sshbuf-misc.c,v 1.18 2022/01/22 00:43:43 djm Exp $ */
/*
* Copyright (c) 2011 Damien Miller
*
@ -30,6 +30,7 @@
#include <string.h>
#include <resolv.h>
#include <ctype.h>
#include <unistd.h>
#include "ssherr.h"
#define SSHBUF_INTERNAL
@ -269,3 +270,39 @@ sshbuf_find(const struct sshbuf *b, size_t start_offset,
*offsetp = (const u_char *)p - sshbuf_ptr(b);
return 0;
}
int
sshbuf_read(int fd, struct sshbuf *buf, size_t maxlen, size_t *rlen)
{
int r, oerrno;
size_t adjust;
ssize_t rr;
u_char *d;
if (rlen != NULL)
*rlen = 0;
if ((r = sshbuf_reserve(buf, maxlen, &d)) != 0)
return r;
rr = read(fd, d, maxlen);
oerrno = errno;
/* Adjust the buffer to include only what was actually read */
if ((adjust = maxlen - (rr > 0 ? rr : 0)) != 0) {
if ((r = sshbuf_consume_end(buf, adjust)) != 0) {
/* avoid returning uninitialised data to caller */
memset(d + rr, '\0', adjust);
return SSH_ERR_INTERNAL_ERROR; /* shouldn't happen */
}
}
if (rr < 0) {
errno = oerrno;
return SSH_ERR_SYSTEM_ERROR;
} else if (rr == 0) {
errno = EPIPE;
return SSH_ERR_SYSTEM_ERROR;
}
/* success */
if (rlen != NULL)
*rlen = (size_t)rr;
return 0;
}

View File

@ -1,4 +1,4 @@
/* $OpenBSD: sshbuf.h,v 1.24 2022/01/01 05:55:06 jsg Exp $ */
/* $OpenBSD: sshbuf.h,v 1.25 2022/01/22 00:43:43 djm Exp $ */
/*
* Copyright (c) 2011 Damien Miller
*
@ -309,6 +309,10 @@ int sshbuf_load_file(const char *, struct sshbuf **)
int sshbuf_write_file(const char *path, struct sshbuf *buf)
__attribute__((__nonnull__ (2)));
/* Read up to maxlen bytes from a fd directly to a buffer */
int sshbuf_read(int, struct sshbuf *, size_t, size_t *)
__attribute__((__nonnull__ (2)));
/* Macros for decoding/encoding integers */
#define PEEK_U64(p) \
(((u_int64_t)(((const u_char *)(p))[0]) << 56) | \