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 "error.h"
  26 #include <h/utils.h>
  27 #include <pwd.h>
  28
  29 static FILE *cfile;
  30
  31 #define TOK_EOF 0
  32 #define DEFAULT 1
  33 #define LOGIN   2
  34 #define PASSWD  3
  35 #define ACCOUNT 4
  36 #define MACDEF  5
  37 #define ID      10
  38 #define MACH    11
  39
  40 #define MAX_TOKVAL_SIZE 1024 /* Including terminating NUL. */
  41
  42 struct toktab {
  43     char *tokstr;
  44     int tval;
  45 };
  46
  47 static struct toktab toktabs[] = {
  48     { "",         TOK_EOF },
  49     { "default",  DEFAULT },
  50     { "login",    LOGIN },
  51     { "password", PASSWD },
  52     { "passwd",   PASSWD },
  53     { "account",  ACCOUNT },
  54     { "machine",  MACH },
  55     { "macdef",   MACDEF },
  56     { 0,          0 }
  57 };
  58
  59 /*
  60  * prototypes
  61  */
  62 static int token(char *);
  63
  64
  65 void
  66 ruserpass(const char *host, char **aname, char **apass, int flags)
  67 {
  68     int t;
  69     struct stat stb;
  70
  71     init_credentials_file ();
  72
  73     cfile = fopen (credentials_file, "r");
  74     if (cfile == NULL) {
  75         if (errno != ENOENT)
  76             perror (credentials_file);
  77     } else {
  78         char tokval[MAX_TOKVAL_SIZE];
  79         tokval[0] = '\0';
  80
  81         bool usedefault = false;
  82         while ((t = token(tokval))) {
  83             switch(t) {
  84             case DEFAULT:
  85                 usedefault = true;
  86                 /* FALLTHRU */
  87
  88             case MACH:
  89                 if (!usedefault) {
  90                     if (token(tokval) != ID)
  91                         continue;
  92                     /*
  93                      * Allow match either for user's host name.
  94                      */
  95                     if (strcasecmp(host, tokval) == 0)
  96                         goto match;
  97                     continue;
  98                 }
  99             match:
 100                 while ((t = token(tokval)) && t != MACH && t != DEFAULT) {
 101                     switch(t) {
 102                     case LOGIN:
 103                         if (token(tokval) && *aname == 0)
 104                             *aname = mh_xstrdup(tokval);
 105                         break;
 106
 107                     case PASSWD:
 108                         if (!credentials_no_perm_check &&
 109                             fstat(fileno(cfile), &stb) >= 0 &&
 110                             (stb.st_mode & 077) != 0) {
 111                             /* We make this a fatal error to force the
 112                                user to correct it. */
 113                             inform("group or other permissions, %#o, "
 114                                 "forbidden: %s", stb.st_mode, credentials_file);
 115                             die("Remove password or correct file "
 116                                   "permissions.");
 117                         }
 118                         if (token(tokval) && *apass == 0)
 119                             *apass = mh_xstrdup(tokval);
 120                         break;
 121
 122                     case ACCOUNT:
 123                         break;
 124
 125                     case MACDEF:
 126                         fclose(cfile);
 127                         return;
 128
 129                     default:
 130                         fprintf(stderr,
 131                                 "Unknown keyword %s in credentials file %s\n",
 132                                 tokval, credentials_file);
 133                         break;
 134                     }
 135                 }
 136                 return;
 137             }
 138         }
 139     }
 140
 141     if (!*aname && ! (flags & RUSERPASS_NO_PROMPT_USER)) {
 142         char tmp[80];
 143         char *myname;
 144
 145         if ((myname = getlogin()) == NULL) {
 146             struct passwd *pp;
 147
 148             if ((pp = getpwuid (getuid())) != NULL)
 149                 myname = pp->pw_name;
 150         }
 151         printf("Name (%s:%s): ", host, myname);
 152
 153         if (fgets(tmp, sizeof tmp, stdin) == NULL) {
 154             advise ("tmp", "fgets");
 155         }
 156         trim_suffix_c(tmp, '\n');
 157         if (*tmp != '\0' || myname == NULL) {
 158             myname = tmp;
 159         }
 160
 161         *aname = mh_xstrdup(myname);
 162     }
 163
 164     if (!*apass && ! (flags & RUSERPASS_NO_PROMPT_PASSWORD)) {
 165         char prompt[256];
 166         char *mypass;
 167
 168         snprintf(prompt, sizeof(prompt), "Password (%s:%s): ", host, *aname);
 169         mypass = nmh_getpass(prompt);
 170
 171         if (*mypass == '\0') {
 172             mypass = *aname;
 173         }
 174
 175         *aname = mh_xstrdup(mypass);
 176     }
 177
 178 }
 179
 180 static int
 181 token(char *tokval)
 182 {
 183     int c;
 184     const char normalStop[] = "\t\n ,"; /* Each breaks a word. */
 185     const char *stop;
 186     char *cp;
 187     struct toktab *t;
 188
 189     if (feof(cfile) || ferror(cfile))
 190         return TOK_EOF;
 191
 192     stop = normalStop;
 193     while ((c = getc(cfile)) != EOF && c && strchr(stop, c))
 194         ;
 195     if (c == EOF)
 196         return TOK_EOF;
 197
 198     cp = tokval;
 199     if (c == '"')
 200         /* FIXME: Where is the quoted-string syntax of netrc documented?
 201          * This code treats «"foo""bar"» as two tokens without further
 202          * separators. */
 203         stop = "\"";
 204     else
 205         /* Might be backslash.  Get it again later.  It's handled then. */
 206         if (ungetc(c, cfile) == EOF)
 207             return TOK_EOF;
 208
 209     while ((c = getc(cfile)) != EOF && c && !strchr(stop, c)) {
 210         if (c == '\\' && (c = getc(cfile)) == EOF)
 211             return TOK_EOF; /* Discard whole token. */
 212
 213         *cp++ = c;
 214         if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 215             die("credential tokens restricted to length %d",
 216                   MAX_TOKVAL_SIZE - 1);
 217         }
 218     }
 219     *cp = '\0';
 220
 221     for (t = toktabs; t->tokstr; t++)
 222         if (!strcmp(t->tokstr, tokval))
 223             return t->tval;
 224
 225     return ID;
 226 }