1 /*
2  * This file and its contents are supplied under the terms of the
3  * Common Development and Distribution License ("CDDL"), version 1.0.
4  * You may only use this file in accordance with the terms of version
5  * 1.0 of the CDDL.
6  *
7  * A full copy of the text of the CDDL should have accompanied this
8  * source.  A copy of the CDDL is also available via the Internet at
9  * http://www.illumos.org/license/CDDL.
10  */
11 
12 /*
13  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
14  */
15 
16 /*
17  * fork/exec a privileged helper to do the bind.
18  */
19 
20 #include <stdio.h>
21 #include <string.h>
22 #include <unistd.h>
23 #include <errno.h>
24 #include <sys/types.h>
25 #include <sys/wait.h>
26 #include <sys/socket.h>
27 #include <sys/note.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30 
31 int
ksocket_bind_helper(int fd,struct sockaddr * addr,uint_t addrlen)32 ksocket_bind_helper(int fd, struct sockaddr *addr, uint_t addrlen)
33 {
34 	char familystr[8];
35 	char portstr[12];
36 	char addrstr[INET6_ADDRSTRLEN];
37 	char *argv[6];
38 	const char *p;
39 	/* LINTED E_BAD_PTR_CAST_ALIGN */
40 	struct sockaddr_in  *sin  = (struct sockaddr_in *)addr;
41 	/* LINTED E_BAD_PTR_CAST_ALIGN */
42 	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr;
43 	int pid, err, stat;
44 	_NOTE(ARGUNUSED(addrlen));
45 
46 	(void) snprintf(familystr, sizeof (familystr), "%d", addr->sa_family);
47 	switch (addr->sa_family) {
48 	case AF_INET:
49 		(void) snprintf(portstr, sizeof (portstr), "%d",
50 		    ntohs(sin->sin_port));
51 		p = inet_ntop(AF_INET, &sin->sin_addr,
52 		    addrstr, sizeof (addrstr));
53 		break;
54 	case AF_INET6:
55 		(void) snprintf(portstr, sizeof (portstr), "%d",
56 		    ntohs(sin6->sin6_port));
57 		p = inet_ntop(AF_INET6, &sin6->sin6_addr,
58 		    addrstr, sizeof (addrstr));
59 		break;
60 	default:
61 		p = NULL;
62 		break;
63 	}
64 	if (p == NULL) {
65 		err = errno;
66 		(void) fprintf(stdout, "ksocket_bind_helper, inet_ntop %s\n",
67 		    strerror(err));
68 		return (err);
69 	}
70 
71 	(void) fprintf(stdout, "ksocket_bind_helper, "
72 	    "family=%s addr=%s port=%s\n",
73 	    familystr, addrstr, portstr);
74 
75 	argv[0] = "/usr/bin/pfexec";
76 	argv[1] = "/usr/lib/smbsrv/bind-helper";
77 	argv[2] = familystr;
78 	argv[3] = addrstr;
79 	argv[4] = portstr;
80 	argv[5] = NULL;
81 
82 	pid = vfork();
83 	if (pid == -1) {
84 		err = errno;
85 		perror("fork");
86 		return (err);
87 	}
88 	if (pid == 0) {
89 		(void) dup2(fd, 0);
90 		(void) execv(argv[0], argv);
91 		err = errno;
92 		perror("execv");
93 		return (err);
94 	}
95 	err = waitpid(pid, &stat, 0);
96 	if (err == -1) {
97 		err = errno;
98 		perror("waitpid");
99 		return (err);
100 	}
101 	if (WIFEXITED(stat)) {
102 		err = WEXITSTATUS(stat);
103 		if (err == 0)
104 			return (0);
105 		(void) fprintf(stderr, "helper exit %d\n", err);
106 	}
107 	return (EACCES);
108 }
109