xref: /dragonfly/sys/kern/kern_jail.c (revision 984263bc)
1 /*
2  * ----------------------------------------------------------------------------
3  * "THE BEER-WARE LICENSE" (Revision 42):
4  * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
5  * can do whatever you want with this stuff. If we meet some day, and you think
6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7  * ----------------------------------------------------------------------------
8  *
9  * $FreeBSD: src/sys/kern/kern_jail.c,v 1.6.2.3 2001/08/17 01:00:26 rwatson Exp $
10  *
11  */
12 
13 #include <sys/param.h>
14 #include <sys/types.h>
15 #include <sys/kernel.h>
16 #include <sys/systm.h>
17 #include <sys/errno.h>
18 #include <sys/sysproto.h>
19 #include <sys/malloc.h>
20 #include <sys/proc.h>
21 #include <sys/jail.h>
22 #include <sys/socket.h>
23 #include <sys/sysctl.h>
24 #include <net/if.h>
25 #include <netinet/in.h>
26 
27 MALLOC_DEFINE(M_PRISON, "prison", "Prison structures");
28 
29 SYSCTL_NODE(, OID_AUTO, jail, CTLFLAG_RW, 0,
30     "Jail rules");
31 
32 int	jail_set_hostname_allowed = 1;
33 SYSCTL_INT(_jail, OID_AUTO, set_hostname_allowed, CTLFLAG_RW,
34     &jail_set_hostname_allowed, 0,
35     "Processes in jail can set their hostnames");
36 
37 int	jail_socket_unixiproute_only = 1;
38 SYSCTL_INT(_jail, OID_AUTO, socket_unixiproute_only, CTLFLAG_RW,
39     &jail_socket_unixiproute_only, 0,
40     "Processes in jail are limited to creating UNIX/IPv4/route sockets only");
41 
42 int	jail_sysvipc_allowed = 0;
43 SYSCTL_INT(_jail, OID_AUTO, sysvipc_allowed, CTLFLAG_RW,
44     &jail_sysvipc_allowed, 0,
45     "Processes in jail can use System V IPC primitives");
46 
47 int
48 jail(p, uap)
49         struct proc *p;
50         struct jail_args /* {
51                 syscallarg(struct jail *) jail;
52         } */ *uap;
53 {
54 	int error;
55 	struct prison *pr;
56 	struct jail j;
57 	struct chroot_args ca;
58 
59 	error = suser(p);
60 	if (error)
61 		return (error);
62 	error = copyin(uap->jail, &j, sizeof j);
63 	if (error)
64 		return (error);
65 	if (j.version != 0)
66 		return (EINVAL);
67 	MALLOC(pr, struct prison *, sizeof *pr , M_PRISON, M_WAITOK);
68 	bzero((caddr_t)pr, sizeof *pr);
69 	error = copyinstr(j.hostname, &pr->pr_host, sizeof pr->pr_host, 0);
70 	if (error)
71 		goto bail;
72 	pr->pr_ip = j.ip_number;
73 
74 	ca.path = j.path;
75 	error = chroot(p, &ca);
76 	if (error)
77 		goto bail;
78 
79 	pr->pr_ref++;
80 	p->p_prison = pr;
81 	p->p_flag |= P_JAILED;
82 	return (0);
83 
84 bail:
85 	FREE(pr, M_PRISON);
86 	return (error);
87 }
88 
89 int
90 prison_ip(struct proc *p, int flag, u_int32_t *ip)
91 {
92 	u_int32_t tmp;
93 
94 	if (!p->p_prison)
95 		return (0);
96 	if (flag)
97 		tmp = *ip;
98 	else
99 		tmp = ntohl(*ip);
100 	if (tmp == INADDR_ANY) {
101 		if (flag)
102 			*ip = p->p_prison->pr_ip;
103 		else
104 			*ip = htonl(p->p_prison->pr_ip);
105 		return (0);
106 	}
107 	if (tmp == INADDR_LOOPBACK) {
108 		if (flag)
109 			*ip = p->p_prison->pr_ip;
110 		else
111 			*ip = htonl(p->p_prison->pr_ip);
112 		return (0);
113 	}
114 	if (p->p_prison->pr_ip != tmp)
115 		return (1);
116 	return (0);
117 }
118 
119 void
120 prison_remote_ip(struct proc *p, int flag, u_int32_t *ip)
121 {
122 	u_int32_t tmp;
123 
124 	if (!p || !p->p_prison)
125 		return;
126 	if (flag)
127 		tmp = *ip;
128 	else
129 		tmp = ntohl(*ip);
130 	if (tmp == INADDR_LOOPBACK) {
131 		if (flag)
132 			*ip = p->p_prison->pr_ip;
133 		else
134 			*ip = htonl(p->p_prison->pr_ip);
135 		return;
136 	}
137 	return;
138 }
139 
140 int
141 prison_if(struct proc *p, struct sockaddr *sa)
142 {
143 	struct sockaddr_in *sai = (struct sockaddr_in*) sa;
144 	int ok;
145 
146 	if ((sai->sin_family != AF_INET) && jail_socket_unixiproute_only)
147 		ok = 1;
148 	else if (sai->sin_family != AF_INET)
149 		ok = 0;
150 	else if (p->p_prison->pr_ip != ntohl(sai->sin_addr.s_addr))
151 		ok = 1;
152 	else
153 		ok = 0;
154 	return (ok);
155 }
156