1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/types.h>
34 #include <sys/uio.h>
35 #include <assert.h>
36 #include <errno.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40
41 #include <iscsi_proto.h>
42 #include "libiscsiutil.h"
43
44 int
pdu_ahs_length(const struct pdu * pdu)45 pdu_ahs_length(const struct pdu *pdu)
46 {
47
48 return (pdu->pdu_bhs->bhs_total_ahs_len * 4);
49 }
50
51 int
pdu_data_segment_length(const struct pdu * pdu)52 pdu_data_segment_length(const struct pdu *pdu)
53 {
54 uint32_t len = 0;
55
56 len += pdu->pdu_bhs->bhs_data_segment_len[0];
57 len <<= 8;
58 len += pdu->pdu_bhs->bhs_data_segment_len[1];
59 len <<= 8;
60 len += pdu->pdu_bhs->bhs_data_segment_len[2];
61
62 return (len);
63 }
64
65 void
pdu_set_data_segment_length(struct pdu * pdu,uint32_t len)66 pdu_set_data_segment_length(struct pdu *pdu, uint32_t len)
67 {
68
69 pdu->pdu_bhs->bhs_data_segment_len[2] = len;
70 pdu->pdu_bhs->bhs_data_segment_len[1] = len >> 8;
71 pdu->pdu_bhs->bhs_data_segment_len[0] = len >> 16;
72 }
73
74 struct pdu *
pdu_new(struct connection * conn)75 pdu_new(struct connection *conn)
76 {
77 struct pdu *pdu;
78
79 pdu = calloc(1, sizeof(*pdu));
80 if (pdu == NULL)
81 log_err(1, "calloc");
82
83 pdu->pdu_bhs = calloc(1, sizeof(*pdu->pdu_bhs));
84 if (pdu->pdu_bhs == NULL)
85 log_err(1, "calloc");
86
87 pdu->pdu_connection = conn;
88
89 return (pdu);
90 }
91
92 struct pdu *
pdu_new_response(struct pdu * request)93 pdu_new_response(struct pdu *request)
94 {
95
96 return (pdu_new(request->pdu_connection));
97 }
98
99 static size_t
pdu_padding(const struct pdu * pdu)100 pdu_padding(const struct pdu *pdu)
101 {
102
103 if ((pdu->pdu_data_len % 4) != 0)
104 return (4 - (pdu->pdu_data_len % 4));
105
106 return (0);
107 }
108
109 static void
pdu_read(const struct connection * conn,char * data,size_t len)110 pdu_read(const struct connection *conn, char *data, size_t len)
111 {
112 ssize_t ret;
113
114 while (len > 0) {
115 ret = read(conn->conn_socket, data, len);
116 if (ret < 0) {
117 if (conn->conn_ops->timed_out()) {
118 conn->conn_ops->fail(conn,
119 "Login Phase timeout");
120 log_errx(1, "exiting due to timeout");
121 }
122 conn->conn_ops->fail(conn, strerror(errno));
123 log_err(1, "read");
124 } else if (ret == 0) {
125 conn->conn_ops->fail(conn, "connection lost");
126 log_errx(1, "read: connection lost");
127 }
128 len -= ret;
129 data += ret;
130 }
131 }
132
133 void
pdu_receive(struct pdu * pdu)134 pdu_receive(struct pdu *pdu)
135 {
136 struct connection *conn;
137 size_t len, padding;
138 char dummy[4];
139
140 conn = pdu->pdu_connection;
141 if (conn->conn_use_proxy)
142 return (conn->conn_ops->pdu_receive_proxy(pdu));
143
144 pdu_read(conn, (char *)pdu->pdu_bhs, sizeof(*pdu->pdu_bhs));
145
146 len = pdu_ahs_length(pdu);
147 if (len > 0)
148 log_errx(1, "protocol error: non-empty AHS");
149
150 len = pdu_data_segment_length(pdu);
151 if (len > 0) {
152 if (len > (size_t)conn->conn_max_recv_data_segment_length) {
153 log_errx(1, "protocol error: received PDU "
154 "with DataSegmentLength exceeding %d",
155 conn->conn_max_recv_data_segment_length);
156 }
157
158 pdu->pdu_data_len = len;
159 pdu->pdu_data = malloc(len);
160 if (pdu->pdu_data == NULL)
161 log_err(1, "malloc");
162
163 pdu_read(conn, (char *)pdu->pdu_data, pdu->pdu_data_len);
164
165 padding = pdu_padding(pdu);
166 if (padding != 0) {
167 assert(padding < sizeof(dummy));
168 pdu_read(conn, (char *)dummy, padding);
169 }
170 }
171 }
172
173 void
pdu_send(struct pdu * pdu)174 pdu_send(struct pdu *pdu)
175 {
176 struct connection *conn;
177 ssize_t ret, total_len;
178 size_t padding;
179 uint32_t zero = 0;
180 struct iovec iov[3];
181 int iovcnt;
182
183 conn = pdu->pdu_connection;
184 if (conn->conn_use_proxy)
185 return (conn->conn_ops->pdu_send_proxy(pdu));
186
187 pdu_set_data_segment_length(pdu, pdu->pdu_data_len);
188 iov[0].iov_base = pdu->pdu_bhs;
189 iov[0].iov_len = sizeof(*pdu->pdu_bhs);
190 total_len = iov[0].iov_len;
191 iovcnt = 1;
192
193 if (pdu->pdu_data_len > 0) {
194 iov[1].iov_base = pdu->pdu_data;
195 iov[1].iov_len = pdu->pdu_data_len;
196 total_len += iov[1].iov_len;
197 iovcnt = 2;
198
199 padding = pdu_padding(pdu);
200 if (padding > 0) {
201 assert(padding < sizeof(zero));
202 iov[2].iov_base = &zero;
203 iov[2].iov_len = padding;
204 total_len += iov[2].iov_len;
205 iovcnt = 3;
206 }
207 }
208
209 ret = writev(conn->conn_socket, iov, iovcnt);
210 if (ret < 0) {
211 if (conn->conn_ops->timed_out())
212 log_errx(1, "exiting due to timeout");
213 log_err(1, "writev");
214 }
215 if (ret != total_len)
216 log_errx(1, "short write");
217 }
218
219 void
pdu_delete(struct pdu * pdu)220 pdu_delete(struct pdu *pdu)
221 {
222
223 free(pdu->pdu_data);
224 free(pdu->pdu_bhs);
225 free(pdu);
226 }
227