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 * $FreeBSD$ 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 /* Implicitly fail if already in jail. */ 60 error = suser(p); 61 if (error) 62 return (error); 63 error = copyin(uap->jail, &j, sizeof j); 64 if (error) 65 return (error); 66 if (j.version != 0) 67 return (EINVAL); 68 MALLOC(pr, struct prison *, sizeof *pr , M_PRISON, M_WAITOK | M_ZERO); 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 p->p_ucred = crcopy(p->p_ucred); 80 p->p_ucred->cr_prison = pr; 81 pr->pr_ref = 1; 82 return (0); 83 84 bail: 85 FREE(pr, M_PRISON); 86 return (error); 87 } 88 89 void 90 prison_free(struct prison *pr) 91 { 92 93 pr->pr_ref--; 94 if (pr->pr_ref == 0) { 95 if (pr->pr_linux != NULL) 96 FREE(pr->pr_linux, M_PRISON); 97 FREE(pr, M_PRISON); 98 } 99 } 100 101 void 102 prison_hold(struct prison *pr) 103 { 104 105 pr->pr_ref++; 106 } 107 108 int 109 prison_ip(struct ucred *cred, int flag, u_int32_t *ip) 110 { 111 u_int32_t tmp; 112 113 if (!jailed(cred)) 114 return (0); 115 if (flag) 116 tmp = *ip; 117 else 118 tmp = ntohl(*ip); 119 if (tmp == INADDR_ANY) { 120 if (flag) 121 *ip = cred->cr_prison->pr_ip; 122 else 123 *ip = htonl(cred->cr_prison->pr_ip); 124 return (0); 125 } 126 if (tmp == INADDR_LOOPBACK) { 127 if (flag) 128 *ip = cred->cr_prison->pr_ip; 129 else 130 *ip = htonl(cred->cr_prison->pr_ip); 131 return (0); 132 } 133 if (cred->cr_prison->pr_ip != tmp) 134 return (1); 135 return (0); 136 } 137 138 void 139 prison_remote_ip(struct ucred *cred, int flag, u_int32_t *ip) 140 { 141 u_int32_t tmp; 142 143 if (!jailed(cred)) 144 return; 145 if (flag) 146 tmp = *ip; 147 else 148 tmp = ntohl(*ip); 149 if (tmp == INADDR_LOOPBACK) { 150 if (flag) 151 *ip = cred->cr_prison->pr_ip; 152 else 153 *ip = htonl(cred->cr_prison->pr_ip); 154 return; 155 } 156 return; 157 } 158 159 int 160 prison_if(struct ucred *cred, struct sockaddr *sa) 161 { 162 struct sockaddr_in *sai = (struct sockaddr_in*) sa; 163 int ok; 164 165 if ((sai->sin_family != AF_INET) && jail_socket_unixiproute_only) 166 ok = 1; 167 else if (sai->sin_family != AF_INET) 168 ok = 0; 169 else if (cred->cr_prison->pr_ip != ntohl(sai->sin_addr.s_addr)) 170 ok = 1; 171 else 172 ok = 0; 173 return (ok); 174 } 175 176 /* 177 * Return 0 if jails permit p1 to frob p2, otherwise ESRCH. 178 */ 179 int 180 prison_check(cred1, cred2) 181 struct ucred *cred1, *cred2; 182 { 183 184 if (jailed(cred1)) { 185 if (!jailed(cred2)) 186 return (ESRCH); 187 if (cred2->cr_prison != cred1->cr_prison) 188 return (ESRCH); 189 } 190 191 return (0); 192 } 193 194 /* 195 * Return 1 if the passed credential is in a jail, otherwise 0. 196 */ 197 int 198 jailed(cred) 199 struct ucred *cred; 200 { 201 202 return (cred->cr_prison != NULL); 203 } 204