security.c revision 1.2
1 /* $NetBSD: security.c,v 1.2 2000/06/04 04:51:50 thorpej Exp $ */ 2 3 #include <sys/types.h> 4 #include <sys/time.h> 5 #include <sys/socket.h> 6 #include <netinet/in.h> 7 #include <arpa/inet.h> 8 #include <rpc/rpc.h> 9 #include <rpc/rpcb_prot.h> 10 #include <rpc/pmap_prot.h> 11 #include <err.h> 12 #include <stdlib.h> 13 #include <string.h> 14 #include <unistd.h> 15 #include <util.h> 16 #include <syslog.h> 17 #include <netdb.h> 18 19 /* 20 * XXX for special case checks in check_callit. 21 */ 22 #include <rpcsvc/mount.h> 23 #include <rpcsvc/rquota.h> 24 #include <rpcsvc/nfs_prot.h> 25 #include <rpcsvc/yp.h> 26 #include <rpcsvc/ypclnt.h> 27 #include <rpcsvc/yppasswd.h> 28 29 #include "rpcbind.h" 30 31 #ifdef LIBWRAP 32 # include <tcpd.h> 33 #ifndef LIBWRAP_ALLOW_FACILITY 34 # define LIBWRAP_ALLOW_FACILITY LOG_AUTH 35 #endif 36 #ifndef LIBWRAP_ALLOW_SEVERITY 37 # define LIBWRAP_ALLOW_SEVERITY LOG_INFO 38 #endif 39 #ifndef LIBWRAP_DENY_FACILITY 40 # define LIBWRAP_DENY_FACILITY LOG_AUTH 41 #endif 42 #ifndef LIBWRAP_DENY_SEVERITY 43 # define LIBWRAP_DENY_SEVERITY LOG_WARNING 44 #endif 45 int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY; 46 int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY; 47 #endif 48 49 #ifndef PORTMAP_LOG_FACILITY 50 # define PORTMAP_LOG_FACILITY LOG_AUTH 51 #endif 52 #ifndef PORTMAP_LOG_SEVERITY 53 # define PORTMAP_LOG_SEVERITY LOG_INFO 54 #endif 55 int log_severity = PORTMAP_LOG_FACILITY|PORTMAP_LOG_SEVERITY; 56 57 extern int verboselog; 58 59 int 60 check_access(SVCXPRT *xprt, rpcproc_t proc, void *args, int rpcbvers) 61 { 62 struct netbuf *caller = svc_getrpccaller(xprt); 63 struct sockaddr *addr = (struct sockaddr *)caller->buf; 64 #ifdef LIBWRAP 65 struct request_info req; 66 #endif 67 rpcprog_t prog = 0; 68 rpcb *rpcbp; 69 struct pmap *pmap; 70 71 /* 72 * The older PMAP_* equivalents have the same numbers, so 73 * they are accounted for here as well. 74 */ 75 switch (proc) { 76 case RPCBPROC_GETADDR: 77 case RPCBPROC_SET: 78 case RPCBPROC_UNSET: 79 if (rpcbvers > PMAPVERS) { 80 rpcbp = (rpcb *)args; 81 prog = rpcbp->r_prog; 82 } else { 83 pmap = (struct pmap *)args; 84 prog = pmap->pm_prog; 85 } 86 if (proc == RPCBPROC_GETADDR) 87 break; 88 if (!insecure && !is_loopback(caller)) { 89 if (verboselog) 90 logit(log_severity, addr, proc, prog, 91 " declined (non-loopback sender)"); 92 return 0; 93 } 94 break; 95 case RPCBPROC_CALLIT: 96 case RPCBPROC_INDIRECT: 97 case RPCBPROC_DUMP: 98 case RPCBPROC_GETTIME: 99 case RPCBPROC_UADDR2TADDR: 100 case RPCBPROC_TADDR2UADDR: 101 case RPCBPROC_GETVERSADDR: 102 case RPCBPROC_GETADDRLIST: 103 case RPCBPROC_GETSTAT: 104 default: 105 } 106 107 #ifdef LIBWRAP 108 request_init(&req, RQ_DAEMON, "rpcbind", RQ_CLIENT_SIN, addr, 0); 109 sock_methods(&req); 110 if(!hosts_access(&req)) { 111 logit(deny_severity, addr, proc, prog, ": request from unauthorized host"); 112 return 0; 113 } 114 #endif 115 if (verboselog) 116 logit(log_severity, addr, proc, prog, ""); 117 return 1; 118 } 119 120 int 121 is_loopback(struct netbuf *nbuf) 122 { 123 struct sockaddr *addr = (struct sockaddr *)nbuf->buf; 124 struct sockaddr_in *sin; 125 #ifdef INET6 126 struct sockaddr_in6 *sin6; 127 #endif 128 129 switch (addr->sa_family) { 130 case AF_INET: 131 if (!oldstyle_local) 132 return 0; 133 sin = (struct sockaddr_in *)addr; 134 return ((sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) && 135 (sin->sin_port < IPPORT_RESERVED)); 136 #ifdef INET6 137 case AF_INET6: 138 if (!oldstyle_local) 139 return 0; 140 sin6 = (struct sockaddr_in6 *)addr; 141 return (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr) && 142 (sin6->sin6_port < IPPORT_RESERVED)); 143 #endif 144 case AF_LOCAL: 145 return 1; 146 default: 147 } 148 149 return 0; 150 } 151 152 153 /* logit - report events of interest via the syslog daemon */ 154 void 155 logit(int severity, struct sockaddr *addr, rpcproc_t procnum, rpcprog_t prognum, 156 const char *text) 157 { 158 const char *procname; 159 char procbuf[32]; 160 char *progname; 161 char progbuf[32]; 162 char fromname[NI_MAXHOST]; 163 struct rpcent *rpc; 164 static const char *procmap[] = { 165 /* RPCBPROC_NULL */ "null", 166 /* RPCBPROC_SET */ "set", 167 /* RPCBPROC_UNSET */ "unset", 168 /* RPCBPROC_GETADDR */ "getport/addr", 169 /* RPCBPROC_DUMP */ "dump", 170 /* RPCBPROC_CALLIT */ "callit", 171 /* RPCBPROC_GETTIME */ "gettime", 172 /* RPCBPROC_UADDR2TADDR */ "uaddr2taddr", 173 /* RPCBPROC_TADDR2UADDR */ "taddr2uaddr", 174 /* RPCBPROC_GETVERSADDR */ "getversaddr", 175 /* RPCBPROC_INDIRECT */ "indirect", 176 /* RPCBPROC_GETADDRLIST */ "getaddrlist", 177 /* RPCBPROC_GETSTAT */ "getstat" 178 }; 179 180 /* 181 * Fork off a process or the portmap daemon might hang while 182 * getrpcbynumber() or syslog() does its thing. 183 */ 184 185 if (fork() == 0) { 186 setproctitle("logit"); 187 188 /* Try to map program number to name. */ 189 190 if (prognum == 0) { 191 progname = ""; 192 } else if ((rpc = getrpcbynumber((int) prognum))) { 193 progname = rpc->r_name; 194 } else { 195 snprintf(progname = progbuf, sizeof(progbuf), "%u", 196 (unsigned)prognum); 197 } 198 199 /* Try to map procedure number to name. */ 200 201 if (procnum > (sizeof procmap / sizeof (char *))) { 202 snprintf(procbuf, sizeof procbuf, "%u", 203 (unsigned)procnum); 204 procname = procbuf; 205 } else 206 procname = procmap[procnum]; 207 208 /* Write syslog record. */ 209 210 if (addr->sa_family == AF_LOCAL) 211 strcpy(fromname, "local"); 212 else 213 getnameinfo(addr, addr->sa_len, fromname, 214 sizeof fromname, NULL, 0, NI_NUMERICHOST); 215 216 syslog(severity, "connect from %s to %s(%s)%s", 217 fromname, procname, progname, text); 218 _exit(0); 219 } 220 } 221 222 int 223 check_callit(SVCXPRT *xprt, struct r_rmtcall_args *args, int versnum) 224 { 225 struct sockaddr *sa = (struct sockaddr *)svc_getrpccaller(xprt)->buf; 226 227 /* 228 * Always allow calling NULLPROC 229 */ 230 if (args->rmt_proc == 0) 231 return 1; 232 233 /* 234 * XXX - this special casing sucks. 235 */ 236 switch (args->rmt_prog) { 237 case RPCBPROG: 238 /* 239 * Allow indirect calls to ourselves in insecure mode. 240 * The is_loopback checks aren't useful then anyway. 241 */ 242 if (!insecure) 243 goto deny; 244 break; 245 case MOUNTPROG: 246 if (args->rmt_proc != MOUNTPROC_MNT && 247 args->rmt_proc != MOUNTPROC_UMNT) 248 break; 249 goto deny; 250 case YPBINDPROG: 251 if (args->rmt_proc != YPBINDPROC_SETDOM) 252 break; 253 /* FALLTHROUGH */ 254 case YPPASSWDPROG: 255 case NFS_PROGRAM: 256 case RQUOTAPROG: 257 goto deny; 258 case YPPROG: 259 switch (args->rmt_proc) { 260 case YPPROC_ALL: 261 case YPPROC_MATCH: 262 case YPPROC_FIRST: 263 case YPPROC_NEXT: 264 goto deny; 265 default: 266 } 267 default: 268 } 269 270 return 1; 271 deny: 272 logit(deny_severity, sa, args->rmt_proc, args->rmt_prog, 273 ": indirect call not allowed"); 274 275 return 0; 276 } 277
Indexes created Thu Sep 25 16:09:42 GMT 2025