xref: /freebsd-13.1/usr.sbin/iscsid/pdu.c (revision bce7ee9d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2012 The FreeBSD Foundation
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from 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 AUTHOR 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 AUTHOR 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 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/types.h>
36 #include <sys/uio.h>
37 #include <assert.h>
38 #include <errno.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 #include "iscsid.h"
44 #include "iscsi_proto.h"
45 
46 #ifdef ICL_KERNEL_PROXY
47 #include <sys/ioctl.h>
48 #endif
49 
50 static int
pdu_ahs_length(const struct pdu * pdu)51 pdu_ahs_length(const struct pdu *pdu)
52 {
53 
54 	return (pdu->pdu_bhs->bhs_total_ahs_len * 4);
55 }
56 
57 static int
pdu_data_segment_length(const struct pdu * pdu)58 pdu_data_segment_length(const struct pdu *pdu)
59 {
60 	uint32_t len = 0;
61 
62 	len += pdu->pdu_bhs->bhs_data_segment_len[0];
63 	len <<= 8;
64 	len += pdu->pdu_bhs->bhs_data_segment_len[1];
65 	len <<= 8;
66 	len += pdu->pdu_bhs->bhs_data_segment_len[2];
67 
68 	return (len);
69 }
70 
71 static void
pdu_set_data_segment_length(struct pdu * pdu,uint32_t len)72 pdu_set_data_segment_length(struct pdu *pdu, uint32_t len)
73 {
74 
75 	pdu->pdu_bhs->bhs_data_segment_len[2] = len;
76 	pdu->pdu_bhs->bhs_data_segment_len[1] = len >> 8;
77 	pdu->pdu_bhs->bhs_data_segment_len[0] = len >> 16;
78 }
79 
80 struct pdu *
pdu_new(struct connection * conn)81 pdu_new(struct connection *conn)
82 {
83 	struct pdu *pdu;
84 
85 	pdu = calloc(1, sizeof(*pdu));
86 	if (pdu == NULL)
87 		log_err(1, "calloc");
88 
89 	pdu->pdu_bhs = calloc(1, sizeof(*pdu->pdu_bhs));
90 	if (pdu->pdu_bhs == NULL)
91 		log_err(1, "calloc");
92 
93 	pdu->pdu_connection = conn;
94 
95 	return (pdu);
96 }
97 
98 struct pdu *
pdu_new_response(struct pdu * request)99 pdu_new_response(struct pdu *request)
100 {
101 
102 	return (pdu_new(request->pdu_connection));
103 }
104 
105 #ifdef ICL_KERNEL_PROXY
106 
107 static void
pdu_receive_proxy(struct pdu * pdu)108 pdu_receive_proxy(struct pdu *pdu)
109 {
110 	struct connection *conn;
111 	struct iscsi_daemon_receive *idr;
112 	size_t len;
113 	int error;
114 
115 	conn = pdu->pdu_connection;
116 	assert(conn->conn_conf.isc_iser != 0);
117 
118 	pdu->pdu_data = malloc(conn->conn_max_recv_data_segment_length);
119 	if (pdu->pdu_data == NULL)
120 		log_err(1, "malloc");
121 
122 	idr = calloc(1, sizeof(*idr));
123 	if (idr == NULL)
124 		log_err(1, "calloc");
125 
126 	idr->idr_session_id = conn->conn_session_id;
127 	idr->idr_bhs = pdu->pdu_bhs;
128 	idr->idr_data_segment_len = conn->conn_max_recv_data_segment_length;
129 	idr->idr_data_segment = pdu->pdu_data;
130 
131 	error = ioctl(conn->conn_iscsi_fd, ISCSIDRECEIVE, idr);
132 	if (error != 0)
133 		log_err(1, "ISCSIDRECEIVE");
134 
135 	len = pdu_ahs_length(pdu);
136 	if (len > 0)
137 		log_errx(1, "protocol error: non-empty AHS");
138 
139 	len = pdu_data_segment_length(pdu);
140 	assert(len <= (size_t)conn->conn_max_recv_data_segment_length);
141 	pdu->pdu_data_len = len;
142 
143 	free(idr);
144 }
145 
146 static void
pdu_send_proxy(struct pdu * pdu)147 pdu_send_proxy(struct pdu *pdu)
148 {
149 	struct connection *conn;
150 	struct iscsi_daemon_send *ids;
151 	int error;
152 
153 	conn = pdu->pdu_connection;
154 	assert(conn->conn_conf.isc_iser != 0);
155 
156 	pdu_set_data_segment_length(pdu, pdu->pdu_data_len);
157 
158 	ids = calloc(1, sizeof(*ids));
159 	if (ids == NULL)
160 		log_err(1, "calloc");
161 
162 	ids->ids_session_id = conn->conn_session_id;
163 	ids->ids_bhs = pdu->pdu_bhs;
164 	ids->ids_data_segment_len = pdu->pdu_data_len;
165 	ids->ids_data_segment = pdu->pdu_data;
166 
167 	error = ioctl(conn->conn_iscsi_fd, ISCSIDSEND, ids);
168 	if (error != 0)
169 		log_err(1, "ISCSIDSEND");
170 
171 	free(ids);
172 }
173 
174 #endif /* ICL_KERNEL_PROXY */
175 
176 static size_t
pdu_padding(const struct pdu * pdu)177 pdu_padding(const struct pdu *pdu)
178 {
179 
180 	if ((pdu->pdu_data_len % 4) != 0)
181 		return (4 - (pdu->pdu_data_len % 4));
182 
183 	return (0);
184 }
185 
186 static void
pdu_read(const struct connection * conn,char * data,size_t len)187 pdu_read(const struct connection *conn, char *data, size_t len)
188 {
189 	ssize_t ret;
190 
191 	while (len > 0) {
192 		ret = read(conn->conn_socket, data, len);
193 		if (ret < 0) {
194 			if (timed_out()) {
195 				fail(conn, "Login Phase timeout");
196 				log_errx(1, "exiting due to timeout");
197 			}
198 			fail(conn, strerror(errno));
199 			log_err(1, "read");
200 		} else if (ret == 0) {
201 			fail(conn, "connection lost");
202 			log_errx(1, "read: connection lost");
203 		}
204 		len -= ret;
205 		data += ret;
206 	}
207 }
208 
209 void
pdu_receive(struct pdu * pdu)210 pdu_receive(struct pdu *pdu)
211 {
212 	struct connection *conn;
213 	size_t len, padding;
214 	char dummy[4];
215 
216 	conn = pdu->pdu_connection;
217 #ifdef ICL_KERNEL_PROXY
218 	if (conn->conn_conf.isc_iser != 0)
219 		return (pdu_receive_proxy(pdu));
220 #endif
221 	assert(conn->conn_conf.isc_iser == 0);
222 
223 	pdu_read(conn, (char *)pdu->pdu_bhs, sizeof(*pdu->pdu_bhs));
224 
225 	len = pdu_ahs_length(pdu);
226 	if (len > 0)
227 		log_errx(1, "protocol error: non-empty AHS");
228 
229 	len = pdu_data_segment_length(pdu);
230 	if (len > 0) {
231 		if (len > (size_t)conn->conn_max_recv_data_segment_length) {
232 			log_errx(1, "protocol error: received PDU "
233 			    "with DataSegmentLength exceeding %d",
234 			    conn->conn_max_recv_data_segment_length);
235 		}
236 
237 		pdu->pdu_data_len = len;
238 		pdu->pdu_data = malloc(len);
239 		if (pdu->pdu_data == NULL)
240 			log_err(1, "malloc");
241 
242 		pdu_read(conn, (char *)pdu->pdu_data, pdu->pdu_data_len);
243 
244 		padding = pdu_padding(pdu);
245 		if (padding != 0) {
246 			assert(padding < sizeof(dummy));
247 			pdu_read(conn, (char *)dummy, padding);
248 		}
249 	}
250 }
251 
252 void
pdu_send(struct pdu * pdu)253 pdu_send(struct pdu *pdu)
254 {
255 	struct connection *conn;
256 	ssize_t ret, total_len;
257 	size_t padding;
258 	uint32_t zero = 0;
259 	struct iovec iov[3];
260 	int iovcnt;
261 
262 	conn = pdu->pdu_connection;
263 #ifdef ICL_KERNEL_PROXY
264 	if (conn->conn_conf.isc_iser != 0)
265 		return (pdu_send_proxy(pdu));
266 #endif
267 
268 	assert(conn->conn_conf.isc_iser == 0);
269 
270 	pdu_set_data_segment_length(pdu, pdu->pdu_data_len);
271 	iov[0].iov_base = pdu->pdu_bhs;
272 	iov[0].iov_len = sizeof(*pdu->pdu_bhs);
273 	total_len = iov[0].iov_len;
274 	iovcnt = 1;
275 
276 	if (pdu->pdu_data_len > 0) {
277 		iov[1].iov_base = pdu->pdu_data;
278 		iov[1].iov_len = pdu->pdu_data_len;
279 		total_len += iov[1].iov_len;
280 		iovcnt = 2;
281 
282 		padding = pdu_padding(pdu);
283 		if (padding > 0) {
284 			assert(padding < sizeof(zero));
285 			iov[2].iov_base = &zero;
286 			iov[2].iov_len = padding;
287 			total_len += iov[2].iov_len;
288 			iovcnt = 3;
289 		}
290 	}
291 
292 	ret = writev(conn->conn_socket, iov, iovcnt);
293 	if (ret < 0) {
294 		if (timed_out())
295 			log_errx(1, "exiting due to timeout");
296 		log_err(1, "writev");
297 	}
298 	if (ret != total_len)
299 		log_errx(1, "short write");
300 }
301 
302 void
pdu_delete(struct pdu * pdu)303 pdu_delete(struct pdu *pdu)
304 {
305 
306 	free(pdu->pdu_data);
307 	free(pdu->pdu_bhs);
308 	free(pdu);
309 }
310