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