contrib/tcp_wrappers/scaffold.c

   1  /*
   2   * Routines for testing only. Not really industrial strength.
   3   *
   4   * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
   5   *
   6   * $FreeBSD: src/contrib/tcp_wrappers/scaffold.c,v 1.2.2.1 2000/07/18 08:34:55 ume Exp $
   7   * $DragonFly: src/contrib/tcp_wrappers/scaffold.c,v 1.3 2005/09/04 01:53:07 sephe Exp $
   8   */
   9
  10 #ifndef lint
  11 static char sccs_id[] = "@(#) scaffold.c 1.6 97/03/21 19:27:24";
  12 #endif
  13
  14 /* System libraries. */
  15
  16 #include <sys/types.h>
  17 #include <sys/stat.h>
  18 #include <sys/socket.h>
  19 #include <netinet/in.h>
  20 #include <arpa/inet.h>
  21 #include <netdb.h>
  22 #include <stdio.h>
  23 #include <syslog.h>
  24 #include <setjmp.h>
  25 #include <string.h>
  26
  27 #ifndef INADDR_NONE
  28 #define INADDR_NONE     (-1)            /* XXX should be 0xffffffff */
  29 #endif
  30
  31 #ifndef INET6
  32 #include <stdlib.h>
  33 #endif
  34
  35 /* Application-specific. */
  36
  37 #include "tcpd.h"
  38 #include "scaffold.h"
  39
  40  /*
  41   * These are referenced by the options module and by rfc931.c.
  42   */
  43 int     allow_severity = SEVERITY;
  44 int     deny_severity = LOG_WARNING;
  45 int     rfc931_timeout = RFC931_TIMEOUT;
  46
  47 #ifndef INET6
  48 /* dup_hostent - create hostent in one memory block */
  49
  50 static struct hostent *dup_hostent(hp)
  51 struct hostent *hp;
  52 {
  53     struct hostent_block {
  54         struct hostent host;
  55         char   *addr_list[1];
  56     };
  57     struct hostent_block *hb;
  58     int     count;
  59     char   *data;
  60     char   *addr;
  61
  62     for (count = 0; hp->h_addr_list[count] != 0; count++)
  63          /* void */ ;
  64
  65     if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
  66                          + (hp->h_length + sizeof(char *)) * count)) == 0) {
  67         fprintf(stderr, "Sorry, out of memory\n");
  68         exit(1);
  69     }
  70     memset((char *) &hb->host, 0, sizeof(hb->host));
  71     hb->host.h_length = hp->h_length;
  72     hb->host.h_addr_list = hb->addr_list;
  73     hb->host.h_addr_list[count] = 0;
  74     data = (char *) (hb->host.h_addr_list + count + 1);
  75
  76     for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
  77         hb->host.h_addr_list[count] = data + hp->h_length * count;
  78         memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
  79     }
  80     return (&hb->host);
  81 }
  82 #endif
  83
  84 /* find_inet_addr - find all addresses for this host, result to free() */
  85
  86 #ifdef INET6
  87 struct addrinfo *find_inet_addr(host)
  88 char   *host;
  89 {
  90     struct addrinfo hints, *res;
  91
  92     memset(&hints, 0, sizeof(hints));
  93     hints.ai_family = PF_UNSPEC;
  94     hints.ai_socktype = SOCK_STREAM;
  95     hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST;
  96     if (getaddrinfo(host, NULL, &hints, &res) == 0)
  97         return (res);
  98
  99     memset(&hints, 0, sizeof(hints));
 100     hints.ai_family = PF_UNSPEC;
 101     hints.ai_socktype = SOCK_STREAM;
 102     hints.ai_flags = AI_PASSIVE | AI_CANONNAME;
 103     if (getaddrinfo(host, NULL, &hints, &res) != 0) {
 104         tcpd_warn("%s: host not found", host);
 105         return (0);
 106     }
 107     if (res->ai_family != AF_INET6 && res->ai_family != AF_INET) {
 108         tcpd_warn("%d: not an internet host", res->ai_family);
 109         freeaddrinfo(res);
 110         return (0);
 111     }
 112     if (!res->ai_canonname) {
 113         tcpd_warn("%s: hostname alias", host);
 114         tcpd_warn("(cannot obtain official name)", res->ai_canonname);
 115     } else if (STR_NE(host, res->ai_canonname)) {
 116         tcpd_warn("%s: hostname alias", host);
 117         tcpd_warn("(official name: %.*s)", STRING_LENGTH, res->ai_canonname);
 118     }
 119     return (res);
 120 }
 121 #else
 122 struct hostent *find_inet_addr(host)
 123 char   *host;
 124 {
 125     struct in_addr addr;
 126     struct hostent *hp;
 127     static struct hostent h;
 128     static char *addr_list[2];
 129
 130     /*
 131      * Host address: translate it to internal form.
 132      */
 133     if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
 134         h.h_addr_list = addr_list;
 135         h.h_addr_list[0] = (char *) &addr;
 136         h.h_length = sizeof(addr);
 137         return (dup_hostent(&h));
 138     }
 139
 140     /*
 141      * Map host name to a series of addresses. Watch out for non-internet
 142      * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
 143      * been "enhanced" to accept numeric addresses. Make a copy of the
 144      * address list so that later gethostbyXXX() calls will not clobber it.
 145      */
 146     if (NOT_INADDR(host) == 0) {
 147         tcpd_warn("%s: not an internet address", host);
 148         return (0);
 149     }
 150     if ((hp = gethostbyname(host)) == 0) {
 151         tcpd_warn("%s: host not found", host);
 152         return (0);
 153     }
 154     if (hp->h_addrtype != AF_INET) {
 155         tcpd_warn("%d: not an internet host", hp->h_addrtype);
 156         return (0);
 157     }
 158     if (STR_NE(host, hp->h_name)) {
 159         tcpd_warn("%s: hostname alias", host);
 160         tcpd_warn("(official name: %.*s)", STRING_LENGTH, hp->h_name);
 161     }
 162     return (dup_hostent(hp));
 163 }
 164 #endif
 165
 166 /* check_dns - give each address thorough workout, return address count */
 167
 168 int     check_dns(host)
 169 char   *host;
 170 {
 171     struct request_info request;
 172 #ifdef INET6
 173     struct sockaddr_storage sin;
 174     struct addrinfo *hp, *res;
 175 #else
 176     struct sockaddr_in sin;
 177     struct hostent *hp;
 178 #endif
 179     int     count;
 180     char   *addr;
 181
 182     if ((hp = find_inet_addr(host)) == 0)
 183         return (0);
 184     request_init(&request, RQ_CLIENT_SIN, &sin, 0);
 185     sock_methods(&request);
 186 #ifndef INET6
 187     memset((char *) &sin, 0, sizeof(sin));
 188     sin.sin_family = AF_INET;
 189 #endif
 190
 191 #ifdef INET6
 192     for (res = hp, count = 0; res; res = res->ai_next, count++) {
 193         memcpy(&sin, res->ai_addr, res->ai_addrlen);
 194 #else
 195     for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
 196         memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));
 197 #endif
 198
 199         /*
 200          * Force host name and address conversions. Use the request structure
 201          * as a cache. Detect hostname lookup problems. Any name/name or
 202          * name/address conflicts will be reported while eval_hostname() does
 203          * its job.
 204          */
 205         request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
 206         if (STR_EQ(eval_hostname(request.client), unknown))
 207             tcpd_warn("host address %s->name lookup failed",
 208                       eval_hostaddr(request.client));
 209     }
 210 #ifdef INET6
 211     freeaddrinfo(hp);
 212 #else
 213     free((char *) hp);
 214 #endif
 215     return (count);
 216 }
 217
 218 /* dummy function to intercept the real shell_cmd() */
 219
 220 /* ARGSUSED */
 221
 222 void    shell_cmd(command)
 223 char   *command;
 224 {
 225     if (hosts_access_verbose)
 226         printf("command: %s", command);
 227 }
 228
 229 /* dummy function  to intercept the real clean_exit() */
 230
 231 /* ARGSUSED */
 232
 233 void    clean_exit(request)
 234 struct request_info *request;
 235 {
 236     exit(0);
 237 }
 238
 239 /* check_path - examine accessibility */
 240
 241 int     check_path(path, st)
 242 char   *path;
 243 struct stat *st;
 244 {
 245     struct stat stbuf;
 246     char    buf[BUFSIZ];
 247
 248     if (stat(path, st) < 0)
 249         return (-1);
 250 #ifdef notdef
 251     if (st->st_uid != 0)
 252         tcpd_warn("%s: not owned by root", path);
 253     if (st->st_mode & 020)
 254         tcpd_warn("%s: group writable", path);
 255 #endif
 256     if (st->st_mode & 002)
 257         tcpd_warn("%s: world writable", path);
 258     if (path[0] == '/' && path[1] != 0) {
 259         strrchr(strcpy(buf, path), '/')[0] = 0;
 260         (void) check_path(buf[0] ? buf : "/", &stbuf);
 261     }
 262     return (0);
 263 }