external/ibm-public/postfix/dist/src/util/host_port.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      host_port 3
   6 /* SUMMARY
   7 /*      split string into host and port, destroy string
   8 /* SYNOPSIS
   9 /*      #include <host_port.h>
  10 /*
  11 /*      const char *host_port(string, host, def_host, port, def_service)
  12 /*      char    *string;
  13 /*      char    **host;
  14 /*      char    *def_host;
  15 /*      char    **port;
  16 /*      char    *def_service;
  17 /* DESCRIPTION
  18 /*      host_port() splits a string into substrings with the host
  19 /*      name or address, and the service name or port number.
  20 /*      The input string is modified.
  21 /*
  22 /*      The following input formats are understood (null means
  23 /*      a null pointer argument):
  24 /*
  25 /*      When def_service is not null, and def_host is null:
  26 /*
  27 /*              [host]:port, [host]:, [host]
  28 /*
  29 /*              host:port, host:, host
  30 /*
  31 /*      When def_host is not null, and def_service is null:
  32 /*
  33 /*              :port, port
  34 /*
  35 /*      Other combinations of def_service and def_host are
  36 /*      not supported and produce undefined results.
  37 /* DIAGNOSTICS
  38 /*      The result is a null pointer in case of success.
  39 /*      In case of problems the result is a string pointer with
  40 /*      the problem type.
  41 /* CLIENT EXAMPLE
  42 /* .ad
  43 /* .fi
  44 /*      Typical client usage allows the user to omit the service port,
  45 /*      in which case the client connects to a pre-determined default
  46 /*      port:
  47 /* .nf
  48 /* .na
  49 /*
  50 /*      buf = mystrdup(endpoint);
  51 /*      if ((parse_error = host_port(buf, &host, NULL, &port, defport)) != 0)
  52 /*          msg_fatal("%s in \"%s\"", parse_error, endpoint);
  53 /*      if ((aierr = hostname_to_sockaddr(host, port, SOCK_STREAM, &res)) != 0)
  54 /*          msg_fatal("%s: %s", endpoint, MAI_STRERROR(aierr));
  55 /*      myfree(buf);
  56 /* SERVER EXAMPLE
  57 /* .ad
  58 /* .fi
  59 /*      Typical server usage allows the user to omit the host, meaning
  60 /*      listen on all available network addresses:
  61 /* .nf
  62 /* .na
  63 /*
  64 /*      buf = mystrdup(endpoint);
  65 /*      if ((parse_error = host_port(buf, &host, "", &port, NULL)) != 0)
  66 /*          msg_fatal("%s in \"%s\"", parse_error, endpoint);
  67 /*      if (*host == 0)
  68 /*          host = 0;
  69 /*      if ((aierr = hostname_to_sockaddr(host, port, SOCK_STREAM, &res)) != 0)
  70 /*          msg_fatal("%s: %s", endpoint, MAI_STRERROR(aierr));
  71 /*      myfree(buf);
  72 /* LICENSE
  73 /* .ad
  74 /* .fi
  75 /*      The Secure Mailer license must be distributed with this software.
  76 /* AUTHOR(S)
  77 /*      Wietse Venema
  78 /*      IBM T.J. Watson Research
  79 /*      P.O. Box 704
  80 /*      Yorktown Heights, NY 10598, USA
  81 /*--*/
  82
  83 /* System library. */
  84
  85 #include <sys_defs.h>
  86 #include <string.h>
  87 #include <ctype.h>
  88
  89 /* Utility library. */
  90
  91 #include <msg.h>
  92 #include <split_at.h>
  93 #include <stringops.h>
  94 #include <valid_hostname.h>
  95
  96 /* Global library. */
  97
  98 #include <host_port.h>
  99
 100 /* host_port - parse string into host and port, destroy string */
 101
 102 const char *host_port(char *buf, char **host, char *def_host,
 103                               char **port, char *def_service)
 104 {
 105     char   *cp = buf;
 106
 107     /*
 108      * [host]:port, [host]:, [host].
 109      */
 110     if (*cp == '[') {
 111         *host = ++cp;
 112         if ((cp = split_at(cp, ']')) == 0)
 113             return ("missing \"]\"");
 114         if (*cp && *cp++ != ':')
 115             return ("garbage after \"]\"");
 116         *port = *cp ? cp : def_service;
 117     }
 118
 119     /*
 120      * host:port, host:, host, :port, port.
 121      */
 122     else {
 123         if ((cp = split_at_right(buf, ':')) != 0) {
 124             *host = *buf ? buf : def_host;
 125             *port = *cp ? cp : def_service;
 126         } else {
 127             *host = def_host ? def_host : (*buf ? buf : 0);
 128             *port = def_service ? def_service : (*buf ? buf : 0);
 129         }
 130     }
 131     if (*host == 0)
 132         return ("missing host information");
 133     if (*port == 0)
 134         return ("missing service information");
 135
 136     /*
 137      * Final sanity checks. We're still sloppy, allowing bare numerical
 138      * network addresses instead of requiring proper [ipaddress] forms.
 139      */
 140     if (*host != def_host && !valid_hostname(*host, DONT_GRIPE)
 141         && !valid_hostaddr(*host, DONT_GRIPE))
 142         return ("valid hostname or network address required");
 143     if (*port != def_service && ISDIGIT(**port) && !alldig(*port))
 144         return ("garbage after numerical service");
 145     return (0);
 146 }
 147
 148 #ifdef TEST
 149
 150 #include <vstream.h>
 151 #include <vstring.h>
 152 #include <vstring_vstream.h>
 153
 154 #define STR(x) vstring_str(x)
 155
 156 int     main(int unused_argc, char **unused_argv)
 157 {
 158     VSTRING *in_buf = vstring_alloc(10);
 159     VSTRING *parse_buf = vstring_alloc(10);
 160     char   *host;
 161     char   *port;
 162     const char *err;
 163
 164     while (vstring_fgets_nonl(in_buf, VSTREAM_IN)) {
 165         vstream_printf(">> %s\n", STR(in_buf));
 166         vstream_fflush(VSTREAM_OUT);
 167         if (*STR(in_buf) == '#')
 168             continue;
 169         vstring_strcpy(parse_buf, STR(in_buf));
 170         if ((err = host_port(STR(parse_buf), &host, (char *) 0, &port, "default-service")) != 0) {
 171             msg_warn("%s in %s", err, STR(in_buf));
 172         } else {
 173             vstream_printf("host %s port %s\n", host, port);
 174             vstream_fflush(VSTREAM_OUT);
 175         }
 176     }
 177     vstring_free(in_buf);
 178     vstring_free(parse_buf);
 179     return (0);
 180 }
 181
 182 #endif