diplodocus.org Git - nmh/blob - sbr/ruserpass.c

   1 /*
   2  * Portions of this code are
   3  * Copyright (c) 1985 Regents of the University of California.
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms are permitted
   7  * provided that the above copyright notice and this paragraph are
   8  * duplicated in all such forms and that any documentation,
   9  * advertising materials, and other materials related to such
  10  * distribution and use acknowledge that the software was developed
  11  * by the University of California, Berkeley.  The name of the
  12  * University may not be used to endorse or promote products derived
  13  * from this software without specific prior written permission.
  14  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  17  *
  18  * Portions of this code are Copyright (c) 2013, by the authors of
  19  * nmh.  See the COPYRIGHT file in the root directory of the nmh
  20  * distribution for complete copyright information.
  21  */
  22
  23 #include <h/mh.h>
  24 #include <h/utils.h>
  25 #include <pwd.h>
  26
  27 static FILE *cfile;
  28
  29 #define DEFAULT 1
  30 #define LOGIN   2
  31 #define PASSWD  3
  32 #define ACCOUNT 4
  33 #define MACDEF  5
  34 #define ID      10
  35 #define MACH    11
  36
  37 #define MAX_TOKVAL_SIZE 1024
  38
  39 struct toktab {
  40     char *tokstr;
  41     int tval;
  42 };
  43
  44 static struct toktab toktabs[] = {
  45     { "default",  DEFAULT },
  46     { "login",    LOGIN },
  47     { "password", PASSWD },
  48     { "passwd",   PASSWD },
  49     { "account",  ACCOUNT },
  50     { "machine",  MACH },
  51     { "macdef",   MACDEF },
  52     { 0,          0 }
  53 };
  54
  55 /*
  56  * prototypes
  57  */
  58 static int token(char *);
  59
  60
  61 void
  62 ruserpass(char *host, char **aname, char **apass)
  63 {
  64     int t, usedefault = 0;
  65     struct stat stb;
  66
  67     init_credentials_file ();
  68
  69     cfile = fopen (credentials_file, "r");
  70     if (cfile == NULL) {
  71         if (errno != ENOENT)
  72             perror (credentials_file);
  73     } else {
  74         char tokval[MAX_TOKVAL_SIZE];
  75         tokval[0] = '\0';
  76
  77         while ((t = token(tokval))) {
  78             switch(t) {
  79             case DEFAULT:
  80                 usedefault = 1;
  81                 /* FALL THROUGH */
  82
  83             case MACH:
  84                 if (!usedefault) {
  85                     if (token(tokval) != ID)
  86                         continue;
  87                     /*
  88                      * Allow match either for user's host name.
  89                      */
  90                     if (strcasecmp(host, tokval) == 0)
  91                         goto match;
  92                     continue;
  93                 }
  94             match:
  95                 while ((t = token(tokval)) && t != MACH && t != DEFAULT) {
  96                     switch(t) {
  97                     case LOGIN:
  98                         if (token(tokval) && *aname == 0) {
  99                             *aname = mh_xmalloc((size_t) strlen(tokval) + 1);
 100                             strcpy(*aname, tokval);
 101                         }
 102                         break;
 103
 104                     case PASSWD:
 105                         if (fstat(fileno(cfile), &stb) >= 0 &&
 106                             (stb.st_mode & 077) != 0) {
 107                             /* We make this a fatal error to force the
 108                                user to correct it. */
 109                             advise(NULL, "Error - file %s must not be world or "
 110                                    "group readable.", credentials_file);
 111                             adios(NULL, "Remove password or correct file "
 112                                   "permissions.");
 113                         }
 114                         if (token(tokval) && *apass == 0) {
 115                             *apass = mh_xmalloc((size_t) strlen(tokval) + 1);
 116                             strcpy(*apass, tokval);
 117                         }
 118                         break;
 119
 120                     case ACCOUNT:
 121                         break;
 122
 123                     case MACDEF:
 124                         fclose(cfile);
 125                         return;
 126
 127                     default:
 128                         fprintf(stderr,
 129                                 "Unknown keyword %s in credentials file %s\n",
 130                                 tokval, credentials_file);
 131                         break;
 132                     }
 133                 }
 134                 return;
 135             }
 136         }
 137     }
 138
 139     if (!*aname) {
 140         char tmp[80];
 141         char *myname;
 142
 143         if ((myname = getlogin()) == NULL) {
 144             struct passwd *pp;
 145
 146             if ((pp = getpwuid (getuid())) != NULL)
 147                 myname = pp->pw_name;
 148         }
 149         printf("Name (%s:%s): ", host, myname);
 150
 151         fgets(tmp, sizeof(tmp) - 1, stdin);
 152         tmp[strlen(tmp) - 1] = '\0';
 153         if (*tmp != '\0') {
 154             myname = tmp;
 155         }
 156
 157         *aname = mh_xmalloc((size_t) strlen(myname) + 1);
 158         strcpy (*aname, myname);
 159     }
 160
 161     if (!*apass) {
 162         char prompt[256];
 163         char *mypass;
 164
 165         snprintf(prompt, sizeof(prompt), "Password (%s:%s): ", host, *aname);
 166         mypass = nmh_getpass(prompt);
 167
 168         if (*mypass == '\0') {
 169             mypass = *aname;
 170         }
 171
 172         *apass = mh_xmalloc((size_t) strlen(mypass) + 1);
 173         strcpy (*apass, mypass);
 174     }
 175
 176 }
 177
 178 static int
 179 token(char *tokval)
 180 {
 181     char *cp;
 182     int c;
 183     struct toktab *t;
 184
 185     if (feof(cfile))
 186         return (0);
 187     while ((c = getc(cfile)) != EOF &&
 188            (c == '\n' || c == '\t' || c == ' ' || c == ','))
 189         continue;
 190     if (c == EOF)
 191         return (0);
 192     cp = tokval;
 193     if (c == '"') {
 194         while ((c = getc(cfile)) != EOF && c != '"') {
 195             if (c == '\\')
 196                 c = getc(cfile);
 197             *cp++ = c;
 198             if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 199                 adios(NULL, "credential tokens restricted to length %d",
 200                       MAX_TOKVAL_SIZE - 1);
 201             }
 202         }
 203     } else {
 204         *cp++ = c;
 205         while ((c = getc(cfile)) != EOF
 206                && c != '\n' && c != '\t' && c != ' ' && c != ',') {
 207             if (c == '\\')
 208                 c = getc(cfile);
 209             *cp++ = c;
 210             if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 211                 adios(NULL, "credential tokens restricted to length %d",
 212                       MAX_TOKVAL_SIZE - 1);
 213             }
 214         }
 215     }
 216     *cp = 0;
 217     if (tokval[0] == 0)
 218         return (0);
 219     for (t = toktabs; t->tokstr; t++)
 220         if (!strcmp(t->tokstr, tokval))
 221             return (t->tval);
 222     return (ID);
 223 }