2 * env.c -- small service routines
4 * Copyright 1998 by Eric S. Raymond
5 * For license terms, see the file COPYING in this directory.
15 #ifdef HAVE_NET_SOCKET_H
16 #include <net/socket.h>
19 #include <sys/types.h>
20 #include <sys/socket.h>
21 #include "fetchmail.h"
22 #include "getaddrinfo.h"
25 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS) && defined(HAVE_STRFTIME)
29 #ifndef HAVE_DECL_GETENV
30 extern char *getenv(const char *); /* needed on sysV68 R3V7.1. */
33 void envquery(int argc, char **argv)
34 /* set up basic stuff from the environment (including the rc file name) */
36 struct passwd by_name, by_uid, *pwp;
41 if (!(user = getenv("FETCHMAILUSER")))
43 if (!(user = getenv("LOGNAME")))
45 user = getenv("USER");
49 if ((program_name = strrchr(argv[0], '/')) != NULL)
52 program_name = argv[0];
54 if (getenv("QMAILINJECT") && strcmp(getenv("QMAILINJECT"), ""))
57 GT_("%s: The QMAILINJECT environment variable is set.\n"
58 "This is dangerous as it can make qmail-inject or qmail's sendmail wrapper\n"
59 "tamper with your From: or Message-ID: headers.\n"
60 "Try \"env QMAILINJECT= %s YOUR ARGUMENTS HERE\"\n"
62 program_name, program_name, program_name);
66 if (getenv("NULLMAILER_FLAGS") && strcmp(getenv("NULLMAILER_FLAGS"), ""))
69 GT_("%s: The NULLMAILER_FLAGS environment variable is set.\n"
70 "This is dangerous as it can make nullmailer-inject or nullmailer's\n"
71 "sendmail wrapper tamper with your From:, Message-ID: or Return-Path: headers.\n"
72 "Try \"env NULLMAILER_FLAGS= %s YOUR ARGUMENTS HERE\"\n"
74 program_name, program_name, program_name);
78 if (!(pwp = getpwuid(getuid())))
81 GT_("%s: You don't exist. Go away.\n"),
87 memcpy(&by_uid, pwp, sizeof(struct passwd));
88 if (!user || !(pwp = getpwnam(user)))
93 * This logic is needed to handle gracefully the possibility
94 * that multiple names might be mapped to one UID.
96 memcpy(&by_name, pwp, sizeof(struct passwd));
98 if (by_name.pw_uid == by_uid.pw_uid)
103 user = xstrdup(pwp->pw_name);
108 /* compute user's home directory */
109 home = getenv("HOME_ETC");
110 if (!home && !(home = getenv("HOME")))
111 home = xstrdup(pwp->pw_dir);
113 /* compute fetchmail's home directory */
114 if (!(fmhome = getenv("FETCHMAILHOME")))
117 #define RCFILE_NAME "fetchmailrc"
119 * The (fmhome==home) leaves an extra character for a . at the
120 * beginning of the rc file's name, iff fetchmail is using $HOME
121 * for its files. We don't want to do that if fetchmail has its
122 * own home ($FETCHMAILHOME), however.
124 rcfile = (char *)xmalloc(strlen(fmhome)+sizeof(RCFILE_NAME)+(fmhome==home)+2);
125 /* avoid //.fetchmailrc */
126 if (strcmp(fmhome, "/") != 0)
127 strcpy(rcfile, fmhome);
131 if (rcfile[strlen(rcfile) - 1] != '/')
135 strcat(rcfile, RCFILE_NAME);
138 char *host_fqdn(int required)
140 char tmpbuf[HOSTLEN+1];
143 if (gethostname(tmpbuf, sizeof(tmpbuf)))
145 fprintf(stderr, GT_("%s: can't determine your host!"),
150 /* if we got no . in the hostname, try to canonicalize it,
151 * else assume it is a FQDN */
152 if (strchr(tmpbuf, '.') == NULL)
154 /* if we got a basename without dots, as we often do in Linux,
155 * look up canonical name (make a FQDN of it) */
156 struct addrinfo hints, *res;
159 memset(&hints, 0, sizeof hints);
160 hints.ai_family = AF_UNSPEC;
161 hints.ai_socktype = SOCK_STREAM;
162 hints.ai_flags = AI_CANONNAME;
164 e = fm_getaddrinfo(tmpbuf, NULL, &hints, &res);
166 /* exit with error message */
168 GT_("gethostbyname failed for %s\n"), tmpbuf);
169 fprintf(stderr, "%s", gai_strerror(e));
170 fprintf(stderr, GT_("Cannot find my own host in hosts database to qualify it!\n"));
174 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"));
175 return xstrdup(tmpbuf);
179 result = xstrdup(res->ai_canonname ? res->ai_canonname : tmpbuf);
180 fm_freeaddrinfo(res);
183 result = xstrdup(tmpbuf);
188 static char *tzoffset(time_t *now)
189 /* calculate timezone offset */
191 static char offset_string[6];
198 off = (lt->tm_hour - gmt.tm_hour) * 60 + lt->tm_min - gmt.tm_min;
199 if (lt->tm_year < gmt.tm_year)
201 else if (lt->tm_year > gmt.tm_year)
203 else if (lt->tm_yday < gmt.tm_yday)
205 else if (lt->tm_yday > gmt.tm_yday)
211 if (off >= 24 * 60) /* should be impossible */
212 off = 23 * 60 + 59; /* if not, insert silly value */
213 snprintf(offset_string, sizeof(offset_string),
214 "%c%02d%02d", sign, off / 60, off % 60);
215 return (offset_string);
218 char *rfc822timestamp(void)
219 /* return a timestamp in RFC822 form */
227 * Conform to RFC822. We generate a 4-digit year here, avoiding
228 * Y2K hassles. Max length of this timestamp in an English locale
229 * should be 29 chars. The only things that should vary by locale
230 * are the day and month abbreviations. The set_locale calls prevent
231 * weird multibyte i18n characters (such as kanji) from showing up
232 * in your Received headers.
234 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS)
235 setlocale (LC_TIME, "C");
237 strftime(buf, sizeof(buf)-1,
238 "%a, %d %b %Y %H:%M:%S XXXXX (%Z)", localtime(&now));
239 #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS)
240 setlocale (LC_TIME, "");
242 strncpy(strstr(buf, "XXXXX"), tzoffset(&now), 5);
245 * This is really just a portability fallback, as the
246 * date format ctime(3) emits is not RFC822
249 strlcpy(buf, ctime(&now), sizeof(buf));
250 buf[strlen(buf)-1] = '\0'; /* remove trailing \n */
251 #endif /* HAVE_STRFTIME */
256 const char *showproto(int proto)
257 /* protocol index to protocol name mapping */
261 case P_AUTO: return("auto");
263 case P_POP3: return("POP3");
264 case P_APOP: return("APOP");
265 case P_RPOP: return("RPOP");
266 #endif /* POP3_ENABLE */
268 case P_IMAP: return("IMAP");
269 #endif /* IMAP_ENABLE */
271 case P_ETRN: return("ETRN");
272 #endif /* ETRN_ENABLE */
274 case P_ODMR: return("ODMR");
275 #endif /* ODMR_ENABLE */
276 default: return("unknown?!?");
280 char *visbuf(const char *buf)
281 /* visibilize a given string */
288 needed = strlen(buf) * 5 + 1; /* worst case: HEX, plus NUL byte */
290 if (!vbuf || needed > vbufs) {
292 vbuf = (char *)xrealloc(vbuf, vbufs);
299 if (*buf == '"') { *tp++ = '\\'; *tp++ = '"'; buf++; }
300 else if (*buf == '\\') { *tp++ = '\\'; *tp++ = '\\'; buf++; }
301 else if (isprint((unsigned char)*buf) || *buf == ' ') *tp++ = *buf++;
302 else if (*buf == '\a') { *tp++ = '\\'; *tp++ = 'a'; buf++; }
303 else if (*buf == '\b') { *tp++ = '\\'; *tp++ = 'b'; buf++; }
304 else if (*buf == '\f') { *tp++ = '\\'; *tp++ = 'f'; buf++; }
305 else if (*buf == '\n') { *tp++ = '\\'; *tp++ = 'n'; buf++; }
306 else if (*buf == '\r') { *tp++ = '\\'; *tp++ = 'r'; buf++; }
307 else if (*buf == '\t') { *tp++ = '\\'; *tp++ = 't'; buf++; }
308 else if (*buf == '\v') { *tp++ = '\\'; *tp++ = 'v'; buf++; }
311 const char hex[] = "0123456789abcdef";
312 *tp++ = '\\'; *tp++ = '0'; *tp++ = 'x';
313 *tp++ = hex[*buf >> 4];
314 *tp++ = hex[*buf & 0xf];
321 /* env.c ends here */