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, usedefault = 0;
  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         while ((t = token(tokval))) {
  81             switch(t) {
  82             case DEFAULT:
  83                 usedefault = 1;
  84                 /* FALLTHRU */
  85
  86             case MACH:
  87                 if (!usedefault) {
  88                     if (token(tokval) != ID)
  89                         continue;
  90                     /*
  91                      * Allow match either for user's host name.
  92                      */
  93                     if (strcasecmp(host, tokval) == 0)
  94                         goto match;
  95                     continue;
  96                 }
  97             match:
  98                 while ((t = token(tokval)) && t != MACH && t != DEFAULT) {
  99                     switch(t) {
 100                     case LOGIN:
 101                         if (token(tokval) && *aname == 0)
 102                             *aname = mh_xstrdup(tokval);
 103                         break;
 104
 105                     case PASSWD:
 106                         if (!credentials_no_perm_check &&
 107                             fstat(fileno(cfile), &stb) >= 0 &&
 108                             (stb.st_mode & 077) != 0) {
 109                             /* We make this a fatal error to force the
 110                                user to correct it. */
 111                             inform("group or other permissions, %#o, "
 112                                 "forbidden: %s", stb.st_mode, credentials_file);
 113                             adios(NULL, "Remove password or correct file "
 114                                   "permissions.");
 115                         }
 116                         if (token(tokval) && *apass == 0)
 117                             *apass = mh_xstrdup(tokval);
 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 && ! (flags & RUSERPASS_NO_PROMPT_USER)) {
 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         if (fgets(tmp, sizeof tmp, stdin) == NULL) {
 152             advise ("tmp", "fgets");
 153         }
 154         trim_suffix_c(tmp, '\n');
 155         if (*tmp != '\0' || myname == NULL) {
 156             myname = tmp;
 157         }
 158
 159         *aname = mh_xstrdup(myname);
 160     }
 161
 162     if (!*apass && ! (flags & RUSERPASS_NO_PROMPT_PASSWORD)) {
 163         char prompt[256];
 164         char *mypass;
 165
 166         snprintf(prompt, sizeof(prompt), "Password (%s:%s): ", host, *aname);
 167         mypass = nmh_getpass(prompt);
 168
 169         if (*mypass == '\0') {
 170             mypass = *aname;
 171         }
 172
 173         *aname = mh_xstrdup(mypass);
 174     }
 175
 176 }
 177
 178 static int
 179 token(char *tokval)
 180 {
 181     int c;
 182     const char normalStop[] = "\t\n ,"; /* Each breaks a word. */
 183     const char *stop;
 184     char *cp;
 185     struct toktab *t;
 186
 187     if (feof(cfile) || ferror(cfile))
 188         return TOK_EOF;
 189
 190     stop = normalStop;
 191     while ((c = getc(cfile)) != EOF && c && strchr(stop, c))
 192         ;
 193     if (c == EOF)
 194         return TOK_EOF;
 195
 196     cp = tokval;
 197     if (c == '"')
 198         /* FIXME: Where is the quoted-string syntax of netrc documented?
 199          * This code treats «"foo""bar"» as two tokens without further
 200          * separators. */
 201         stop = "\"";
 202     else
 203         /* Might be backslash.  Get it again later.  It's handled then. */
 204         if (ungetc(c, cfile) == EOF)
 205             return TOK_EOF;
 206
 207     while ((c = getc(cfile)) != EOF && c && !strchr(stop, c)) {
 208         if (c == '\\' && (c = getc(cfile)) == EOF)
 209             return TOK_EOF; /* Discard whole token. */
 210
 211         *cp++ = c;
 212         if (cp - tokval > MAX_TOKVAL_SIZE-1) {
 213             adios(NULL, "credential tokens restricted to length %d",
 214                   MAX_TOKVAL_SIZE - 1);
 215         }
 216     }
 217     *cp = '\0';
 218
 219     for (t = toktabs; t->tokstr; t++)
 220         if (!strcmp(t->tokstr, tokval))
 221             return t->tval;
 222
 223     return ID;
 224 }