From b01e554d2043e8c85036b483c515c3df854a3a98 Mon Sep 17 00:00:00 2001 From: "Eric S. Raymond" Date: Mon, 20 Jul 1998 04:32:12 +0000 Subject: is_ip_alias -> checkalias. svn path=/trunk/; revision=1983 --- driver.c | 129 --------------------------------------------------------------- 1 file changed, 129 deletions(-) (limited to 'driver.c') diff --git a/driver.c b/driver.c index 220ce41a..f32e471f 100644 --- a/driver.c +++ b/driver.c @@ -45,7 +45,6 @@ #ifdef HAVE_GETHOSTBYNAME #include -#include "mx.h" #endif /* HAVE_GETHOSTBYNAME */ #ifdef KERBEROS_V4 @@ -138,134 +137,6 @@ static void timeout_handler (int signal) #define XMIT_ANTISPAM 3 static int accept_count, reject_count; -#define MX_RETRIES 3 - -extern int is_ip_alias(); - -static int is_host_alias(const char *name, struct query *ctl) -/* determine whether name is a DNS alias of the hostname */ -{ - struct hostent *he,*he_st; - struct mxentry *mxp, *mxrecords; - - struct hostdata *lead_server = - ctl->server.lead_server ? ctl->server.lead_server : &ctl->server; - - /* - * The first two checks are optimizations that will catch a good - * many cases. - * - * (1) check against the `true name' deduced from the poll label - * and the via option (if present) at the beginning of the poll cycle. - * Odds are good this will either be the mailserver's FQDN or a suffix of - * it with the mailserver's domain's default host name omitted. - * - * (2) Then check the rest of the `also known as' - * cache accumulated by previous DNS checks. This cache is primed - * by the aka list option. - * - * Any of these on a mail address is definitive. Only if the - * name doesn't match any is it time to call the bind library. - * If this happens odds are good we're looking at an MX name. - */ - if (strcasecmp(lead_server->truename, name) == 0) - return(TRUE); - else if (str_in_list(&lead_server->akalist, name, TRUE)) - return(TRUE); - else if (!ctl->server.dns) - return(FALSE); - -#ifndef HAVE_RES_SEARCH - return(FALSE); -#else - /* - * The only code that calls the BIND library is here and in the - * start-of-query probe with gethostbyname(3). - * - * We know DNS service was up at the beginning of this poll cycle. - * If it's down, our nameserver has crashed. We don't want to try - * delivering the current message or anything else from this - * mailbox until it's back up. - */ - else if ((he = gethostbyname(name)) != (struct hostent *)NULL) - { - if (strcasecmp(ctl->server.truename, he->h_name) == 0) - goto match; - else if (((he_st = gethostbyname(ctl->server.truename)) != (struct hostent *)NULL) && ctl->server.checkalias) - { - if (outlevel == O_VERBOSE) - error(0, 0, "Checking if %s is really the same node as %s",ctl->server.truename,name); - if (is_ip_alias(ctl->server.truename,name) == TRUE) - { - if (outlevel == O_VERBOSE) - error(0, 0, "Yes, their IP addresses match"); - goto match; - } - if (outlevel == O_VERBOSE) - error(0, 0, "No, their IP addresses don't match"); - } - else - return(FALSE); - } - else - switch (h_errno) - { - case HOST_NOT_FOUND: /* specified host is unknown */ - case NO_ADDRESS: /* valid, but does not have an IP address */ - break; - - case NO_RECOVERY: /* non-recoverable name server error */ - case TRY_AGAIN: /* temporary error on authoritative server */ - default: - if (outlevel != O_SILENT) - putchar('\n'); /* terminate the progress message */ - error(0, 0, - "nameserver failure while looking for `%s' during poll of %s.", - name, ctl->server.pollname); - ctl->errcount++; - break; - } - - /* - * We're only here if DNS was OK but the gethostbyname() failed - * with a HOST_NOT_FOUND or NO_ADDRESS error. - * Search for a name match on MX records pointing to the server. - */ - h_errno = 0; - if ((mxrecords = getmxrecords(name)) == (struct mxentry *)NULL) - { - switch (h_errno) - { - case HOST_NOT_FOUND: /* specified host is unknown */ - case NO_ADDRESS: /* valid, but does not have an IP address */ - return(FALSE); - break; - - case NO_RECOVERY: /* non-recoverable name server error */ - case TRY_AGAIN: /* temporary error on authoritative server */ - default: - error(0, -1, - "nameserver failure while looking for `%s' during poll of %s.", - name, ctl->server.pollname); - ctl->errcount++; - break; - } - } - else - { - for (mxp = mxrecords; mxp->name; mxp++) - if (strcasecmp(ctl->server.truename, mxp->name) == 0) - goto match; - return(FALSE); - match:; - } - - /* add this name to relevant server's `also known as' list */ - save_str(&lead_server->akalist, name, 0); - return(TRUE); -#endif /* HAVE_RES_SEARCH */ -} - static void map_name(name, ctl, xmit_names) /* add given name to xmit_names if it matches declared localnames */ const char *name; /* name to map */ -- cgit v1.2.3