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

   1 /* ruserpass.c -- parse .netrc-format file.
   2  *
   3  * Portions of this code are
   4  * Copyright (c) 1985 Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms are permitted
   8  * provided that the above copyright notice and this paragraph are
   9  * duplicated in all such forms and that any documentation,
  10  * advertising materials, and other materials related to such
  11  * distribution and use acknowledge that the software was developed
  12  * by the University of California, Berkeley.  The name of the
  13  * University may not be used to endorse or promote products derived
  14  * from this software without specific prior written permission.
  15  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  18  *
  19  * Portions of this code are Copyright (c) 2013, by the authors of
  20  * nmh.  See the COPYRIGHT file in the root directory of the nmh
  21  * distribution for complete copyright information.
  22  */
  23
  24 #include "h/mh.h"
  25 #include "getpass.h"
  26 #include "ruserpass.h"
  27 #include "credentials.h"
  28 #include "error.h"
  29 #include "h/utils.h"
  30 #include <pwd.h>
  31
  32 static FILE *cfile;
  33
  34 #define TOK_EOF 0
  35 #define DEFAULT 1
  36 #define LOGIN   2
  37 #define PASSWD  3
  38 #define ACCOUNT 4
  39 #define MACDEF  5
  40 #define ID      10
  41 #define MACH    11
  42
  43 #define MAX_TOKVAL_SIZE 1024 /* Including terminating NUL. */
  44
  45 struct toktab {
  46     char *tokstr;
  47     int tval;
  48 };
  49
  50 static struct toktab toktabs[] = {
  51     { "",         TOK_EOF },
  52     { "default",  DEFAULT },
  53     { "login",    LOGIN },
  54     { "password", PASSWD },
  55     { "passwd",   PASSWD },
  56     { "account",  ACCOUNT },
  57     { "machine",  MACH },
  58     { "macdef",   MACDEF },
  59     { 0,          0 }
  60 };
  61
  62 /*
  63  * prototypes
  64  */
  65 static int token(char *);
  66
  67
  68 void
  69 ruserpass(const char *host, char **aname, char **apass, int flags)
  70 {
  71     int t;
  72     struct stat stb;
  73
  74     init_credentials_file ();
  75
  76     cfile = fopen (credentials_file, "r");
  77     if (cfile == NULL) {
  78         if (errno != ENOENT)
  79             perror (credentials_file);
  80     } else {
  81         char tokval[MAX_TOKVAL_SIZE];
  82         tokval[0] = '\0';
  83
  84         bool usedefault = false;
  85         while ((t = token(tokval))) {
  86             switch(t) {
  87             case DEFAULT:
  88                 usedefault = true;
  89                 /* FALLTHRU */
  90
  91             case MACH:
  92                 if (!usedefault) {
  93                     if (token(tokval) != ID)
  94                         continue;
  95                     /*
  96                      * Allow match either for user's host name.
  97                      */
  98                     if (strcasecmp(host, tokval) == 0)
  99                         goto match;
 100                     continue;
 101                 }
 102             match:
 103                 while ((t = token(tokval)) && t != MACH && t != DEFAULT) {
 104                     switch(t) {
 105                     case LOGIN:
 106                         if (token(tokval) && *aname == 0)
 107                             *aname = mh_xstrdup(tokval);
 108                         break;
 109
 110                     case PASSWD:
 111                         if (!credentials_no_perm_check &&
 112                             fstat(fileno(cfile), &stb) >= 0 &&
 113                             (stb.st_mode & 077) != 0) {
 114                             /* We make this a fatal error to force the
 115                                user to correct it. */
 116                             inform("group or other permissions, %#o, "
 117                                 "forbidden: %s", stb.st_mode, credentials_file);
 118                             die("Remove password or correct file "
 119                                   "permissions.");
 120                         }
 121                         if (token(tokval) && *apass == 0)
 122                             *apass = mh_xstrdup(tokval);
 123                         break;
 124
 125                     case ACCOUNT:
 126                         break;
 127
 128                     case MACDEF:
 129                         fclose(cfile);
 130                         return;
 131
 132                     default:
 133                         fprintf(stderr,
 134                                 "Unknown keyword %s in credentials file %s\n",
 135                                 tokval, credentials_file);
 136                         break;
 137                     }
 138                 }
 139                 return;
 140             }
 141         }
 142     }
 143
 144     if (!*aname && ! (flags & RUSERPASS_NO_PROMPT_USER)) {
 145         char tmp[80];
 146         char *myname;
 147
 148         if ((myname = getlogin()) == NULL) {
 149             struct passwd *pp;
 150
 151             if ((pp = getpwuid (getuid())) != NULL)
 152                 myname = pp->pw_name;
 153         }
 154         printf("Name (%s:%s): ", host, myname);
 155
 156         if (fgets(tmp, sizeof tmp, stdin) == NULL) {
 157             advise ("tmp", "fgets");
 158         }
 159         trim_suffix_c(tmp, '\n');
 160         if (*tmp != '\0' || myname == NULL) {
 161             myname = tmp;
 162         }
 163
 164         *aname = mh_xstrdup(myname);
 165     }
 166
 167     if (!*apass && ! (flags & RUSERPASS_NO_PROMPT_PASSWORD)) {
 168         char prompt[256];
 169         char *mypass;
 170
 171         snprintf(prompt, sizeof(prompt), "Password (%s:%s): ", host, *aname);
 172         mypass = nmh_getpass(prompt);
 173
 174         if (*mypass == '\0') {
 175             mypass = *aname;
 176         }
 177
 178         *aname = mh_xstrdup(mypass);
 179     }
 180
 181 }
 182
 183 static int
 184 token(char *tokval)
 185 {
 186     int c;
 187     const char normalStop[] = "\t\n ,"; /* Each breaks a word. */
 188     const char *stop;
 189     char *cp;
 190     struct toktab *t;
 191
 192     if (feof(cfile) || ferror(cfile))
 193         return TOK_EOF;
 194
 195     stop = normalStop;
 196     while ((c = getc(cfile)) != EOF && c && strchr(stop, c))
 197         ;
 198     if (c == EOF)
 199         return TOK_EOF;
 200
 201     cp = tokval;
 202     if (c == '"')
 203         /* FIXME: Where is the quoted-string syntax of netrc documented?
 204          * This code treats «"foo""bar"» as two tokens without further
 205          * separators. */
 206         stop = "\"";
 207     else
 208         /* Might be backslash.  Get it again later.  It's handled then. */
 209         if (ungetc(c, cfile) == EOF)
 210             return TOK_EOF;
 211
 212     while ((c = getc(cfile)) != EOF && c && !strchr(stop, c)) {
 213         if (c == '\\' && (c = getc(cfile)) == EOF)
 214             return TOK_EOF; /* Discard whole token. */
 215
 216         *cp++ = c;
 217         if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 218             die("credential tokens restricted to length %d",
 219                   MAX_TOKVAL_SIZE - 1);
 220         }
 221     }
 222     *cp = '\0';
 223
 224     for (t = toktabs; t->tokstr; t++)
 225         if (!strcmp(t->tokstr, tokval))
 226             return t->tval;
 227
 228     return ID;
 229 }