/* * env.c -- small service routines * * Copyright 1998 by Eric S. Raymond * For license terms, see the file COPYING in this directory. */ #include "config.h" #include #include #if defined(STDC_HEADERS) #include #endif #if defined(HAVE_UNISTD_H) #include #endif #include #include #ifdef HAVE_NET_SOCKET_H #include #endif #include #include #include #include "fetchmail.h" #include "getaddrinfo.h" #include "i18n.h" #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS) && defined(HAVE_STRFTIME) #include #endif extern char *getenv(const char *); /* needed on sysV68 R3V7.1. */ void envquery(int argc, char **argv) /* set up basic stuff from the environment (including the rc file name) */ { struct passwd by_name, by_uid, *pwp; (void)argc; (void)argc; if (!(user = getenv("FETCHMAILUSER"))) { if (!(user = getenv("LOGNAME"))) { user = getenv("USER"); } } if ((program_name = strrchr(argv[0], '/')) != NULL) ++program_name; else program_name = argv[0]; if (getenv("QMAILINJECT") && strcmp(getenv("QMAILINJECT"), "")) { fprintf(stderr, GT_("%s: The QMAILINJECT environment variable is set.\n" "This is dangerous as it can make qmail-inject or qmail's sendmail wrapper\n" "tamper with your From: or Message-ID: headers.\n" "Try \"env QMAILINJECT= %s YOUR ARGUMENTS HERE\"\n" "%s: Abort.\n"), program_name, program_name, program_name); exit(PS_UNDEFINED); } if (getenv("NULLMAILER_FLAGS") && strcmp(getenv("NULLMAILER_FLAGS"), "")) { fprintf(stderr, GT_("%s: The NULLMAILER_FLAGS environment variable is set.\n" "This is dangerous as it can make nullmailer-inject or nullmailer's\n" "sendmail wrapper tamper with your From:, Message-ID: or Return-Path: headers.\n" "Try \"env NULLMAILER_FLAGS= %s YOUR ARGUMENTS HERE\"\n" "%s: Abort.\n"), program_name, program_name, program_name); exit(PS_UNDEFINED); } if (!(pwp = getpwuid(getuid()))) { fprintf(stderr, GT_("%s: You don't exist. Go away.\n"), program_name); exit(PS_UNDEFINED); } else { memcpy(&by_uid, pwp, sizeof(struct passwd)); if (!user || !(pwp = getpwnam(user))) pwp = &by_uid; else { /* * This logic is needed to handle gracefully the possibility * that multiple names might be mapped to one UID. */ memcpy(&by_name, pwp, sizeof(struct passwd)); if (by_name.pw_uid == by_uid.pw_uid) pwp = &by_name; else pwp = &by_uid; } user = xstrdup(pwp->pw_name); } /* compute user's home directory */ home = getenv("HOME_ETC"); if (!home && !(home = getenv("HOME"))) home = xstrdup(pwp->pw_dir); /* compute fetchmail's home directory */ if (!(fmhome = getenv("FETCHMAILHOME"))) fmhome = home; #define RCFILE_NAME "fetchmailrc" /* * The (fmhome==home) leaves an extra character for a . at the * beginning of the rc file's name, iff fetchmail is using $HOME * for its files. We don't want to do that if fetchmail has its * own home ($FETCHMAILHOME), however. */ rcfile = (char *)xmalloc(strlen(fmhome)+sizeof(RCFILE_NAME)+(fmhome==home)+2); /* avoid //.fetchmailrc */ if (strcmp(fmhome, "/") != 0) strcpy(rcfile, fmhome); else *rcfile = '\0'; if (rcfile[strlen(rcfile) - 1] != '/') strcat(rcfile, "/"); if (fmhome==home) strcat(rcfile, "."); strcat(rcfile, RCFILE_NAME); } char *host_fqdn(int required) { char tmpbuf[HOSTLEN+1]; char *result; if (gethostname(tmpbuf, sizeof(tmpbuf))) { fprintf(stderr, GT_("%s: can't determine your host!"), program_name); exit(PS_DNS); } /* if we got no . in the hostname, try to canonicalize it, * else assume it is a FQDN */ if (strchr(tmpbuf, '.') == NULL) { /* if we got a basename without dots, as we often do in Linux, * look up canonical name (make a FQDN of it) */ struct addrinfo hints, *res; int e; memset(&hints, 0, sizeof hints); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_CANONNAME; e = fm_getaddrinfo(tmpbuf, NULL, &hints, &res); if (e) { /* exit with error message */ fprintf(stderr, GT_("gethostbyname failed for %s\n"), tmpbuf); fprintf(stderr, "%s", gai_strerror(e)); fprintf(stderr, GT_("Cannot find my own host in hosts database to qualify it!\n")); if (required) exit(PS_DNS); else { 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")); return xstrdup(tmpbuf); } } result = xstrdup(res->ai_canonname ? res->ai_canonname : tmpbuf); fm_freeaddrinfo(res); } else result = xstrdup(tmpbuf); return result; } static char *tzoffset(time_t *now) /* calculate timezone offset */ { static char offset_string[6]; struct tm gmt, *lt; int off; char sign = '+'; gmt = *gmtime(now); lt = localtime(now); off = (lt->tm_hour - gmt.tm_hour) * 60 + lt->tm_min - gmt.tm_min; if (lt->tm_year < gmt.tm_year) off -= 24 * 60; else if (lt->tm_year > gmt.tm_year) off += 24 * 60; else if (lt->tm_yday < gmt.tm_yday) off -= 24 * 60; else if (lt->tm_yday > gmt.tm_yday) off += 24 * 60; if (off < 0) { sign = '-'; off = -off; } if (off >= 24 * 60) /* should be impossible */ off = 23 * 60 + 59; /* if not, insert silly value */ snprintf(offset_string, sizeof(offset_string), "%c%02d%02d", sign, off / 60, off % 60); return (offset_string); } char *rfc822timestamp(void) /* return a timestamp in RFC822 form */ { time_t now; static char buf[50]; time(&now); #ifdef HAVE_STRFTIME /* * Conform to RFC822. We generate a 4-digit year here, avoiding * Y2K hassles. Max length of this timestamp in an English locale * should be 29 chars. The only things that should vary by locale * are the day and month abbreviations. The set_locale calls prevent * weird multibyte i18n characters (such as kanji) from showing up * in your Received headers. */ #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS) setlocale (LC_TIME, "C"); #endif strftime(buf, sizeof(buf)-1, "%a, %d %b %Y %H:%M:%S XXXXX (%Z)", localtime(&now)); #if defined(HAVE_SETLOCALE) && defined(ENABLE_NLS) setlocale (LC_TIME, ""); #endif strncpy(strstr(buf, "XXXXX"), tzoffset(&now), 5); #else /* * This is really just a portability fallback, as the * date format ctime(3) emits is not RFC822 * conformant. */ strlcpy(buf, ctime(&now), sizeof(buf)); buf[strlen(buf)-1] = '\0'; /* remove trailing \n */ #endif /* HAVE_STRFTIME */ return(buf); } const char *showproto(int proto) /* protocol index to protocol name mapping */ { switch (proto) { case P_AUTO: return("auto"); #ifdef POP2_ENABLE case P_POP2: return("POP2"); #endif /* POP2_ENABLE */ #ifdef POP3_ENABLE case P_POP3: return("POP3"); case P_APOP: return("APOP"); case P_RPOP: return("RPOP"); #endif /* POP3_ENABLE */ #ifdef IMAP_ENABLE case P_IMAP: return("IMAP"); #endif /* IMAP_ENABLE */ #ifdef ETRN_ENABLE case P_ETRN: return("ETRN"); #endif /* ETRN_ENABLE */ #ifdef ODMR_ENABLE case P_ODMR: return("ODMR"); #endif /* ODMR_ENABLE */ default: return("unknown?!?"); } } char *visbuf(const char *buf) /* visibilize a given string */ { static char *vbuf; static size_t vbufs; char *tp; size_t needed; needed = strlen(buf) * 5 + 1; /* worst case: HEX, plus NUL byte */ if (!vbuf || needed > vbufs) { vbufs = needed; vbuf = (char *)xrealloc(vbuf, vbufs); } tp = vbuf; while (*buf) { if (*buf == '"') { *tp++ = '\\'; *tp++ = '"'; buf++; } else if (*buf == '\\') { *tp++ = '\\'; *tp++ = '\\'; buf++; } else if (isprint((unsigned char)*buf) || *buf == ' ') *tp++ = *buf++; else if (*buf == '\a') { *tp++ = '\\'; *tp++ = 'a'; buf++; } else if (*buf == '\b') { *tp++ = '\\'; *tp++ = 'b'; buf++; } else if (*buf == '\f') { *tp++ = '\\'; *tp++ = 'f'; buf++; } else if (*buf == '\n') { *tp++ = '\\'; *tp++ = 'n'; buf++; } else if (*buf == '\r') { *tp++ = '\\'; *tp++ = 'r'; buf++; } else if (*buf == '\t') { *tp++ = '\\'; *tp++ = 't'; buf++; } else if (*buf == '\v') { *tp++ = '\\'; *tp++ = 'v'; buf++; } else { const char hex[] = "0123456789abcdef"; *tp++ = '\\'; *tp++ = '0'; *tp++ = 'x'; *tp++ = hex[*buf >> 4]; *tp++ = hex[*buf & 0xf]; buf++; } } *tp = '\0'; return(vbuf); } /* env.c ends here */