hast_proto.c revision 225736 
1/*-
2 * Copyright (c) 2009-2010 The FreeBSD Foundation
3 * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>
4 * All rights reserved.
5 *
6 * This software was developed by Pawel Jakub Dawidek under sponsorship from
7 * the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: stable/9/sbin/hastd/hast_proto.c 221078 2011-04-26 19:52:21Z trociny $");
33
34#include <sys/endian.h>
35
36#include <assert.h>
37#include <errno.h>
38#include <strings.h>
39
40#include <hast.h>
41#include <ebuf.h>
42#include <nv.h>
43#include <pjdlog.h>
44#include <proto.h>
45
46#ifdef HAVE_CRYPTO
47#include "hast_checksum.h"
48#endif
49#include "hast_compression.h"
50#include "hast_proto.h"
51
52struct hast_main_header {
53	/* Protocol version. */
54	uint8_t		version;
55	/* Size of nv headers. */
56	uint32_t	size;
57} __packed;
58
59typedef int hps_send_t(const struct hast_resource *, struct nv *nv, void **,
60    size_t *, bool *);
61typedef int hps_recv_t(const struct hast_resource *, struct nv *nv, void **,
62    size_t *, bool *);
63
64struct hast_pipe_stage {
65	const char	*hps_name;
66	hps_send_t	*hps_send;
67	hps_recv_t	*hps_recv;
68};
69
70static struct hast_pipe_stage pipeline[] = {
71	{ "compression", compression_send, compression_recv },
72#ifdef HAVE_CRYPTO
73	{ "checksum", checksum_send, checksum_recv }
74#endif
75};
76
77/*
78 * Send the given nv structure via conn.
79 * We keep headers in nv structure and pass data in separate argument.
80 * There can be no data at all (data is NULL then).
81 */
82int
83hast_proto_send(const struct hast_resource *res, struct proto_conn *conn,
84    struct nv *nv, const void *data, size_t size)
85{
86	struct hast_main_header hdr;
87	struct ebuf *eb;
88	bool freedata;
89	void *dptr, *hptr;
90	size_t hsize;
91	int ret;
92
93	dptr = (void *)(uintptr_t)data;
94	freedata = false;
95	ret = -1;
96
97	if (data != NULL) {
98		unsigned int ii;
99
100		for (ii = 0; ii < sizeof(pipeline) / sizeof(pipeline[0]);
101		    ii++) {
102			(void)pipeline[ii].hps_send(res, nv, &dptr, &size,
103			    &freedata);
104		}
105		nv_add_uint32(nv, size, "size");
106		if (nv_error(nv) != 0) {
107			errno = nv_error(nv);
108			goto end;
109		}
110	}
111
112	eb = nv_hton(nv);
113	if (eb == NULL)
114		goto end;
115
116	hdr.version = HAST_PROTO_VERSION;
117	hdr.size = htole32((uint32_t)ebuf_size(eb));
118	if (ebuf_add_head(eb, &hdr, sizeof(hdr)) < 0)
119		goto end;
120
121	hptr = ebuf_data(eb, &hsize);
122	if (proto_send(conn, hptr, hsize) < 0)
123		goto end;
124	if (data != NULL && proto_send(conn, dptr, size) < 0)
125		goto end;
126
127	ret = 0;
128end:
129	if (freedata)
130		free(dptr);
131	return (ret);
132}
133
134int
135hast_proto_recv_hdr(const struct proto_conn *conn, struct nv **nvp)
136{
137	struct hast_main_header hdr;
138	struct nv *nv;
139	struct ebuf *eb;
140	void *hptr;
141
142	eb = NULL;
143	nv = NULL;
144
145	if (proto_recv(conn, &hdr, sizeof(hdr)) < 0)
146		goto fail;
147
148	if (hdr.version != HAST_PROTO_VERSION) {
149		errno = ERPCMISMATCH;
150		goto fail;
151	}
152
153	hdr.size = le32toh(hdr.size);
154
155	eb = ebuf_alloc(hdr.size);
156	if (eb == NULL)
157		goto fail;
158	if (ebuf_add_tail(eb, NULL, hdr.size) < 0)
159		goto fail;
160	hptr = ebuf_data(eb, NULL);
161	assert(hptr != NULL);
162	if (proto_recv(conn, hptr, hdr.size) < 0)
163		goto fail;
164	nv = nv_ntoh(eb);
165	if (nv == NULL)
166		goto fail;
167
168	*nvp = nv;
169	return (0);
170fail:
171	if (eb != NULL)
172		ebuf_free(eb);
173	return (-1);
174}
175
176int
177hast_proto_recv_data(const struct hast_resource *res, struct proto_conn *conn,
178    struct nv *nv, void *data, size_t size)
179{
180	unsigned int ii;
181	bool freedata;
182	size_t dsize;
183	void *dptr;
184	int ret;
185
186	assert(data != NULL);
187	assert(size > 0);
188
189	ret = -1;
190	freedata = false;
191	dptr = data;
192
193	dsize = nv_get_uint32(nv, "size");
194	if (dsize > size) {
195		errno = EINVAL;
196		goto end;
197	} else if (dsize == 0) {
198		(void)nv_set_error(nv, 0);
199	} else {
200		if (proto_recv(conn, data, dsize) < 0)
201			goto end;
202		for (ii = sizeof(pipeline) / sizeof(pipeline[0]); ii > 0;
203		    ii--) {
204			ret = pipeline[ii - 1].hps_recv(res, nv, &dptr,
205			    &dsize, &freedata);
206			if (ret == -1)
207				goto end;
208		}
209		ret = -1;
210		if (dsize > size) {
211			errno = EINVAL;
212			goto end;
213		}
214		if (dptr != data)
215			bcopy(dptr, data, dsize);
216	}
217
218	ret = 0;
219end:
220	if (freedata)
221		free(dptr);
222	return (ret);
223}
224