1 /*-
2  * Copyright (c) 2009-2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Pawel Jakub Dawidek under sponsorship from
6  * the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 
32 #include <sys/types.h>
33 #include <sys/socket.h>
34 
35 #include <errno.h>
36 #include <stdlib.h>
37 #include <strings.h>
38 
39 #include "pjdlog.h"
40 #include "proto_impl.h"
41 
42 /* Maximum size of packet we want to use when sending data. */
43 #ifndef MAX_SEND_SIZE
44 #define	MAX_SEND_SIZE	32768
45 #endif
46 
47 static int
proto_descriptor_send(int sock,int fd)48 proto_descriptor_send(int sock, int fd)
49 {
50 	unsigned char ctrl[CMSG_SPACE(sizeof(fd))];
51 	struct msghdr msg;
52 	struct cmsghdr *cmsg;
53 
54 	PJDLOG_ASSERT(sock >= 0);
55 	PJDLOG_ASSERT(fd >= 0);
56 
57 	bzero(&msg, sizeof(msg));
58 	bzero(&ctrl, sizeof(ctrl));
59 
60 	msg.msg_iov = NULL;
61 	msg.msg_iovlen = 0;
62 	msg.msg_control = ctrl;
63 	msg.msg_controllen = sizeof(ctrl);
64 
65 	cmsg = CMSG_FIRSTHDR(&msg);
66 	cmsg->cmsg_level = SOL_SOCKET;
67 	cmsg->cmsg_type = SCM_RIGHTS;
68 	cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
69 	bcopy(&fd, CMSG_DATA(cmsg), sizeof(fd));
70 
71 	if (sendmsg(sock, &msg, 0) == -1)
72 		return (errno);
73 
74 	return (0);
75 }
76 
77 int
proto_common_send(int sock,const unsigned char * data,size_t size,int fd)78 proto_common_send(int sock, const unsigned char *data, size_t size, int fd)
79 {
80 	ssize_t done;
81 	size_t sendsize;
82 
83 	PJDLOG_ASSERT(sock >= 0);
84 	PJDLOG_ASSERT(data != NULL);
85 	PJDLOG_ASSERT(size > 0);
86 
87 	do {
88 		sendsize = size < MAX_SEND_SIZE ? size : MAX_SEND_SIZE;
89 		done = send(sock, data, sendsize, MSG_NOSIGNAL);
90 		if (done == 0)
91 			return (ENOTCONN);
92 		else if (done < 0) {
93 			if (errno == EINTR)
94 				continue;
95 			return (errno);
96 		}
97 		data += done;
98 		size -= done;
99 	} while (size > 0);
100 
101 	if (fd == -1)
102 		return (0);
103 	return (proto_descriptor_send(sock, fd));
104 }
105 
106 #include <stdio.h>
107 static int
proto_descriptor_recv(int sock,int * fdp)108 proto_descriptor_recv(int sock, int *fdp)
109 {
110 	unsigned char ctrl[CMSG_SPACE(sizeof(*fdp))];
111 	struct msghdr msg;
112 	struct cmsghdr *cmsg;
113 
114 	PJDLOG_ASSERT(sock >= 0);
115 	PJDLOG_ASSERT(fdp != NULL);
116 
117 	bzero(&msg, sizeof(msg));
118 	bzero(&ctrl, sizeof(ctrl));
119 
120 	msg.msg_iov = NULL;
121 	msg.msg_iovlen = 0;
122 	msg.msg_control = ctrl;
123 	msg.msg_controllen = sizeof(ctrl);
124 
125 	if (recvmsg(sock, &msg, 0) == -1)
126 		return (errno);
127 
128 	cmsg = CMSG_FIRSTHDR(&msg);
129 	if (cmsg->cmsg_level != SOL_SOCKET ||
130 	    cmsg->cmsg_type != SCM_RIGHTS) {
131 		return (EINVAL);
132 	}
133 	bcopy(CMSG_DATA(cmsg), fdp, sizeof(*fdp));
134 
135 	return (0);
136 }
137 
138 int
proto_common_recv(int sock,unsigned char * data,size_t size,int * fdp)139 proto_common_recv(int sock, unsigned char *data, size_t size, int *fdp)
140 {
141 	ssize_t done;
142 
143 	PJDLOG_ASSERT(sock >= 0);
144 	PJDLOG_ASSERT(data != NULL);
145 	PJDLOG_ASSERT(size > 0);
146 
147 	do {
148 		done = recv(sock, data, size, MSG_WAITALL);
149 	} while (done == -1 && errno == EINTR);
150 	if (done == 0)
151 		return (ENOTCONN);
152 	else if (done < 0)
153 		return (errno);
154 	if (fdp == NULL)
155 		return (0);
156 	return (proto_descriptor_recv(sock, fdp));
157 }
158