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 <h/utils.h>
  26 #include <pwd.h>
  27
  28 static FILE *cfile;
  29
  30 #define TOK_EOF 0
  31 #define DEFAULT 1
  32 #define LOGIN   2
  33 #define PASSWD  3
  34 #define ACCOUNT 4
  35 #define MACDEF  5
  36 #define ID      10
  37 #define MACH    11
  38
  39 #define MAX_TOKVAL_SIZE 1024 /* Including terminating NUL. */
  40
  41 struct toktab {
  42     char *tokstr;
  43     int tval;
  44 };
  45
  46 static struct toktab toktabs[] = {
  47     { "",         TOK_EOF },
  48     { "default",  DEFAULT },
  49     { "login",    LOGIN },
  50     { "password", PASSWD },
  51     { "passwd",   PASSWD },
  52     { "account",  ACCOUNT },
  53     { "machine",  MACH },
  54     { "macdef",   MACDEF },
  55     { 0,          0 }
  56 };
  57
  58 /*
  59  * prototypes
  60  */
  61 static int token(char *);
  62
  63
  64 void
  65 ruserpass(const char *host, char **aname, char **apass, int flags)
  66 {
  67     int t;
  68     struct stat stb;
  69
  70     init_credentials_file ();
  71
  72     cfile = fopen (credentials_file, "r");
  73     if (cfile == NULL) {
  74         if (errno != ENOENT)
  75             perror (credentials_file);
  76     } else {
  77         char tokval[MAX_TOKVAL_SIZE];
  78         tokval[0] = '\0';
  79
  80         bool usedefault = false;
  81         while ((t = token(tokval))) {
  82             switch(t) {
  83             case DEFAULT:
  84                 usedefault = true;
  85                 /* FALLTHRU */
  86
  87             case MACH:
  88                 if (!usedefault) {
  89                     if (token(tokval) != ID)
  90                         continue;
  91                     /*
  92                      * Allow match either for user's host name.
  93                      */
  94                     if (strcasecmp(host, tokval) == 0)
  95                         goto match;
  96                     continue;
  97                 }
  98             match:
  99                 while ((t = token(tokval)) && t != MACH && t != DEFAULT) {
 100                     switch(t) {
 101                     case LOGIN:
 102                         if (token(tokval) && *aname == 0)
 103                             *aname = mh_xstrdup(tokval);
 104                         break;
 105
 106                     case PASSWD:
 107                         if (!credentials_no_perm_check &&
 108                             fstat(fileno(cfile), &stb) >= 0 &&
 109                             (stb.st_mode & 077) != 0) {
 110                             /* We make this a fatal error to force the
 111                                user to correct it. */
 112                             inform("group or other permissions, %#o, "
 113                                 "forbidden: %s", stb.st_mode, credentials_file);
 114                             die("Remove password or correct file "
 115                                   "permissions.");
 116                         }
 117                         if (token(tokval) && *apass == 0)
 118                             *apass = mh_xstrdup(tokval);
 119                         break;
 120
 121                     case ACCOUNT:
 122                         break;
 123
 124                     case MACDEF:
 125                         fclose(cfile);
 126                         return;
 127
 128                     default:
 129                         fprintf(stderr,
 130                                 "Unknown keyword %s in credentials file %s\n",
 131                                 tokval, credentials_file);
 132                         break;
 133                     }
 134                 }
 135                 return;
 136             }
 137         }
 138     }
 139
 140     if (!*aname && ! (flags & RUSERPASS_NO_PROMPT_USER)) {
 141         char tmp[80];
 142         char *myname;
 143
 144         if ((myname = getlogin()) == NULL) {
 145             struct passwd *pp;
 146
 147             if ((pp = getpwuid (getuid())) != NULL)
 148                 myname = pp->pw_name;
 149         }
 150         printf("Name (%s:%s): ", host, myname);
 151
 152         if (fgets(tmp, sizeof tmp, stdin) == NULL) {
 153             advise ("tmp", "fgets");
 154         }
 155         trim_suffix_c(tmp, '\n');
 156         if (*tmp != '\0' || myname == NULL) {
 157             myname = tmp;
 158         }
 159
 160         *aname = mh_xstrdup(myname);
 161     }
 162
 163     if (!*apass && ! (flags & RUSERPASS_NO_PROMPT_PASSWORD)) {
 164         char prompt[256];
 165         char *mypass;
 166
 167         snprintf(prompt, sizeof(prompt), "Password (%s:%s): ", host, *aname);
 168         mypass = nmh_getpass(prompt);
 169
 170         if (*mypass == '\0') {
 171             mypass = *aname;
 172         }
 173
 174         *aname = mh_xstrdup(mypass);
 175     }
 176
 177 }
 178
 179 static int
 180 token(char *tokval)
 181 {
 182     int c;
 183     const char normalStop[] = "\t\n ,"; /* Each breaks a word. */
 184     const char *stop;
 185     char *cp;
 186     struct toktab *t;
 187
 188     if (feof(cfile) || ferror(cfile))
 189         return TOK_EOF;
 190
 191     stop = normalStop;
 192     while ((c = getc(cfile)) != EOF && c && strchr(stop, c))
 193         ;
 194     if (c == EOF)
 195         return TOK_EOF;
 196
 197     cp = tokval;
 198     if (c == '"')
 199         /* FIXME: Where is the quoted-string syntax of netrc documented?
 200          * This code treats «"foo""bar"» as two tokens without further
 201          * separators. */
 202         stop = "\"";
 203     else
 204         /* Might be backslash.  Get it again later.  It's handled then. */
 205         if (ungetc(c, cfile) == EOF)
 206             return TOK_EOF;
 207
 208     while ((c = getc(cfile)) != EOF && c && !strchr(stop, c)) {
 209         if (c == '\\' && (c = getc(cfile)) == EOF)
 210             return TOK_EOF; /* Discard whole token. */
 211
 212         *cp++ = c;
 213         if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 214             die("credential tokens restricted to length %d",
 215                   MAX_TOKVAL_SIZE - 1);
 216         }
 217     }
 218     *cp = '\0';
 219
 220     for (t = toktabs; t->tokstr; t++)
 221         if (!strcmp(t->tokstr, tokval))
 222             return t->tval;
 223
 224     return ID;
 225 }