2 * env.c -- small service routines
4 * Copyright 1998 by Eric S. Raymond
5 * For license terms, see the file COPYING in this directory.
11 #if defined(STDC_HEADERS)
14 #if defined(HAVE_UNISTD_H)
19 #ifdef HAVE_NET_SOCKET_H
20 #include <net/socket.h>
23 #include <sys/types.h>
24 #include <sys/socket.h>
25 #include "fetchmail.h"
26 #include "getaddrinfo.h"
29 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS) && defined(HAVE_STRFTIME)
33 #ifndef HAVE_DECL_GETENV
34 extern char *getenv(const char *); /* needed on sysV68 R3V7.1. */
37 void envquery(int argc, char **argv)
38 /* set up basic stuff from the environment (including the rc file name) */
40 struct passwd by_name, by_uid, *pwp;
45 if (!(user = getenv("FETCHMAILUSER")))
47 if (!(user = getenv("LOGNAME")))
49 user = getenv("USER");
53 if ((program_name = strrchr(argv[0], '/')) != NULL)
56 program_name = argv[0];
58 if (getenv("QMAILINJECT") && strcmp(getenv("QMAILINJECT"), ""))
61 GT_("%s: The QMAILINJECT environment variable is set.\n"
62 "This is dangerous as it can make qmail-inject or qmail's sendmail wrapper\n"
63 "tamper with your From: or Message-ID: headers.\n"
64 "Try \"env QMAILINJECT= %s YOUR ARGUMENTS HERE\"\n"
66 program_name, program_name, program_name);
70 if (getenv("NULLMAILER_FLAGS") && strcmp(getenv("NULLMAILER_FLAGS"), ""))
73 GT_("%s: The NULLMAILER_FLAGS environment variable is set.\n"
74 "This is dangerous as it can make nullmailer-inject or nullmailer's\n"
75 "sendmail wrapper tamper with your From:, Message-ID: or Return-Path: headers.\n"
76 "Try \"env NULLMAILER_FLAGS= %s YOUR ARGUMENTS HERE\"\n"
78 program_name, program_name, program_name);
82 if (!(pwp = getpwuid(getuid())))
85 GT_("%s: You don't exist. Go away.\n"),
91 memcpy(&by_uid, pwp, sizeof(struct passwd));
92 if (!user || !(pwp = getpwnam(user)))
97 * This logic is needed to handle gracefully the possibility
98 * that multiple names might be mapped to one UID.
100 memcpy(&by_name, pwp, sizeof(struct passwd));
102 if (by_name.pw_uid == by_uid.pw_uid)
107 user = xstrdup(pwp->pw_name);
112 /* compute user's home directory */
113 home = getenv("HOME_ETC");
114 if (!home && !(home = getenv("HOME")))
115 home = xstrdup(pwp->pw_dir);
117 /* compute fetchmail's home directory */
118 if (!(fmhome = getenv("FETCHMAILHOME")))
121 #define RCFILE_NAME "fetchmailrc"
123 * The (fmhome==home) leaves an extra character for a . at the
124 * beginning of the rc file's name, iff fetchmail is using $HOME
125 * for its files. We don't want to do that if fetchmail has its
126 * own home ($FETCHMAILHOME), however.
128 rcfile = (char *)xmalloc(strlen(fmhome)+sizeof(RCFILE_NAME)+(fmhome==home)+2);
129 /* avoid //.fetchmailrc */
130 if (strcmp(fmhome, "/") != 0)
131 strcpy(rcfile, fmhome);
135 if (rcfile[strlen(rcfile) - 1] != '/')
139 strcat(rcfile, RCFILE_NAME);
142 char *host_fqdn(int required)
144 char tmpbuf[HOSTLEN+1];
147 if (gethostname(tmpbuf, sizeof(tmpbuf)))
149 fprintf(stderr, GT_("%s: can't determine your host!"),
154 /* if we got no . in the hostname, try to canonicalize it,
155 * else assume it is a FQDN */
156 if (strchr(tmpbuf, '.') == NULL)
158 /* if we got a basename without dots, as we often do in Linux,
159 * look up canonical name (make a FQDN of it) */
160 struct addrinfo hints, *res;
163 memset(&hints, 0, sizeof hints);
164 hints.ai_family = AF_UNSPEC;
165 hints.ai_socktype = SOCK_STREAM;
166 hints.ai_flags = AI_CANONNAME;
168 e = fm_getaddrinfo(tmpbuf, NULL, &hints, &res);
170 /* exit with error message */
172 GT_("gethostbyname failed for %s\n"), tmpbuf);
173 fprintf(stderr, "%s", gai_strerror(e));
174 fprintf(stderr, GT_("Cannot find my own host in hosts database to qualify it!\n"));
178 fprintf(stderr, GT_("Trying to continue with unqualified hostname.\nDO NOT report broken Received: headers, HELO/EHLO lines or similar problems!\nDO repair your /etc/hosts, DNS, NIS or LDAP instead.\n"));
179 return xstrdup(tmpbuf);
183 result = xstrdup(res->ai_canonname ? res->ai_canonname : tmpbuf);
184 fm_freeaddrinfo(res);
187 result = xstrdup(tmpbuf);
192 static char *tzoffset(time_t *now)
193 /* calculate timezone offset */
195 static char offset_string[6];
202 off = (lt->tm_hour - gmt.tm_hour) * 60 + lt->tm_min - gmt.tm_min;
203 if (lt->tm_year < gmt.tm_year)
205 else if (lt->tm_year > gmt.tm_year)
207 else if (lt->tm_yday < gmt.tm_yday)
209 else if (lt->tm_yday > gmt.tm_yday)
215 if (off >= 24 * 60) /* should be impossible */
216 off = 23 * 60 + 59; /* if not, insert silly value */
217 snprintf(offset_string, sizeof(offset_string),
218 "%c%02d%02d", sign, off / 60, off % 60);
219 return (offset_string);
222 char *rfc822timestamp(void)
223 /* return a timestamp in RFC822 form */
231 * Conform to RFC822. We generate a 4-digit year here, avoiding
232 * Y2K hassles. Max length of this timestamp in an English locale
233 * should be 29 chars. The only things that should vary by locale
234 * are the day and month abbreviations. The set_locale calls prevent
235 * weird multibyte i18n characters (such as kanji) from showing up
236 * in your Received headers.
238 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS)
239 setlocale (LC_TIME, "C");
241 strftime(buf, sizeof(buf)-1,
242 "%a, %d %b %Y %H:%M:%S XXXXX (%Z)", localtime(&now));
243 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS)
244 setlocale (LC_TIME, "");
246 strncpy(strstr(buf, "XXXXX"), tzoffset(&now), 5);
249 * This is really just a portability fallback, as the
250 * date format ctime(3) emits is not RFC822
253 strlcpy(buf, ctime(&now), sizeof(buf));
254 buf[strlen(buf)-1] = '\0'; /* remove trailing \n */
255 #endif /* HAVE_STRFTIME */
260 const char *showproto(int proto)
261 /* protocol index to protocol name mapping */
265 case P_AUTO: return("auto");
267 case P_POP2: return("POP2");
268 #endif /* POP2_ENABLE */
270 case P_POP3: return("POP3");
271 case P_APOP: return("APOP");
272 case P_RPOP: return("RPOP");
273 #endif /* POP3_ENABLE */
275 case P_IMAP: return("IMAP");
276 #endif /* IMAP_ENABLE */
278 case P_ETRN: return("ETRN");
279 #endif /* ETRN_ENABLE */
281 case P_ODMR: return("ODMR");
282 #endif /* ODMR_ENABLE */
283 default: return("unknown?!?");
287 char *visbuf(const char *buf)
288 /* visibilize a given string */
295 needed = strlen(buf) * 5 + 1; /* worst case: HEX, plus NUL byte */
297 if (!vbuf || needed > vbufs) {
299 vbuf = (char *)xrealloc(vbuf, vbufs);
306 if (*buf == '"') { *tp++ = '\\'; *tp++ = '"'; buf++; }
307 else if (*buf == '\\') { *tp++ = '\\'; *tp++ = '\\'; buf++; }
308 else if (isprint((unsigned char)*buf) || *buf == ' ') *tp++ = *buf++;
309 else if (*buf == '\a') { *tp++ = '\\'; *tp++ = 'a'; buf++; }
310 else if (*buf == '\b') { *tp++ = '\\'; *tp++ = 'b'; buf++; }
311 else if (*buf == '\f') { *tp++ = '\\'; *tp++ = 'f'; buf++; }
312 else if (*buf == '\n') { *tp++ = '\\'; *tp++ = 'n'; buf++; }
313 else if (*buf == '\r') { *tp++ = '\\'; *tp++ = 'r'; buf++; }
314 else if (*buf == '\t') { *tp++ = '\\'; *tp++ = 't'; buf++; }
315 else if (*buf == '\v') { *tp++ = '\\'; *tp++ = 'v'; buf++; }
318 const char hex[] = "0123456789abcdef";
319 *tp++ = '\\'; *tp++ = '0'; *tp++ = 'x';
320 *tp++ = hex[*buf >> 4];
321 *tp++ = hex[*buf & 0xf];
328 /* env.c ends here */