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