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 /* 48 * MPSAFE 49 */ 50 int 51 jail(td, uap) 52 struct thread *td; 53 struct jail_args /* { 54 syscallarg(struct jail *) jail; 55 } */ *uap; 56 { 57 struct proc *p = td->td_proc; 58 int error; 59 struct prison *pr; 60 struct jail j; 61 struct chroot_args ca; 62 63 mtx_lock(&Giant); 64 65 /* Implicitly fail if already in jail. */ 66 error = suser(p); 67 if (error) 68 goto done2; 69 error = copyin(uap->jail, &j, sizeof j); 70 if (error) 71 goto done2; 72 if (j.version != 0) { 73 error = EINVAL; 74 goto done2; 75 } 76 MALLOC(pr, struct prison *, sizeof *pr , M_PRISON, M_WAITOK | M_ZERO); 77 error = copyinstr(j.hostname, &pr->pr_host, sizeof pr->pr_host, 0); 78 if (error) 79 goto bail; 80 pr->pr_ip = j.ip_number; 81 82 ca.path = j.path; 83 error = chroot(td, &ca); 84 if (error) 85 goto bail; 86 87 p->p_ucred = crcopy(p->p_ucred); 88 p->p_ucred->cr_prison = pr; 89 pr->pr_ref = 1; 90 mtx_unlock(&Giant); 91 return (0); 92 93 bail: 94 FREE(pr, M_PRISON); 95 done2: 96 mtx_unlock(&Giant); 97 return (error); 98 } 99 100 void 101 prison_free(struct prison *pr) 102 { 103 104 pr->pr_ref--; 105 if (pr->pr_ref == 0) { 106 if (pr->pr_linux != NULL) 107 FREE(pr->pr_linux, M_PRISON); 108 FREE(pr, M_PRISON); 109 } 110 } 111 112 void 113 prison_hold(struct prison *pr) 114 { 115 116 pr->pr_ref++; 117 } 118 119 int 120 prison_ip(struct ucred *cred, int flag, u_int32_t *ip) 121 { 122 u_int32_t tmp; 123 124 if (!jailed(cred)) 125 return (0); 126 if (flag) 127 tmp = *ip; 128 else 129 tmp = ntohl(*ip); 130 if (tmp == INADDR_ANY) { 131 if (flag) 132 *ip = cred->cr_prison->pr_ip; 133 else 134 *ip = htonl(cred->cr_prison->pr_ip); 135 return (0); 136 } 137 if (tmp == INADDR_LOOPBACK) { 138 if (flag) 139 *ip = cred->cr_prison->pr_ip; 140 else 141 *ip = htonl(cred->cr_prison->pr_ip); 142 return (0); 143 } 144 if (cred->cr_prison->pr_ip != tmp) 145 return (1); 146 return (0); 147 } 148 149 void 150 prison_remote_ip(struct ucred *cred, int flag, u_int32_t *ip) 151 { 152 u_int32_t tmp; 153 154 if (!jailed(cred)) 155 return; 156 if (flag) 157 tmp = *ip; 158 else 159 tmp = ntohl(*ip); 160 if (tmp == INADDR_LOOPBACK) { 161 if (flag) 162 *ip = cred->cr_prison->pr_ip; 163 else 164 *ip = htonl(cred->cr_prison->pr_ip); 165 return; 166 } 167 return; 168 } 169 170 int 171 prison_if(struct ucred *cred, struct sockaddr *sa) 172 { 173 struct sockaddr_in *sai = (struct sockaddr_in*) sa; 174 int ok; 175 176 if ((sai->sin_family != AF_INET) && jail_socket_unixiproute_only) 177 ok = 1; 178 else if (sai->sin_family != AF_INET) 179 ok = 0; 180 else if (cred->cr_prison->pr_ip != ntohl(sai->sin_addr.s_addr)) 181 ok = 1; 182 else 183 ok = 0; 184 return (ok); 185 } 186 187 /* 188 * Return 0 if jails permit p1 to frob p2, otherwise ESRCH. 189 */ 190 int 191 prison_check(cred1, cred2) 192 struct ucred *cred1, *cred2; 193 { 194 195 if (jailed(cred1)) { 196 if (!jailed(cred2)) 197 return (ESRCH); 198 if (cred2->cr_prison != cred1->cr_prison) 199 return (ESRCH); 200 } 201 202 return (0); 203 } 204 205 /* 206 * Return 1 if the passed credential is in a jail, otherwise 0. 207 */ 208 int 209 jailed(cred) 210 struct ucred *cred; 211 { 212 213 return (cred->cr_prison != NULL); 214 } 215