X-Git-Url: https://code.citadel.org/?p=citadel.git;a=blobdiff_plain;f=citadel%2Fdomain.c;h=18764725e093ae357795411e0915d35364a88107;hp=ccf62f7c795753d9d09e65f2b7eb035b903eb11d;hb=51b18018ff923284d76a36cbd421d62abf6afcf4;hpb=4aed8bcc44474e27485a72334805022d6aa604b1 diff --git a/citadel/domain.c b/citadel/domain.c index ccf62f7c7..18764725e 100644 --- a/citadel/domain.c +++ b/citadel/domain.c @@ -1,35 +1,46 @@ /* - * $Id$ - * * DNS lookup for SMTP sender * + * Copyright (c) 1987-2021 by the citadel.org team + * + * This program is open source software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 3. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. */ -#include -#include -#include -#include +#include "sysdep.h" #include +#include +#ifdef HAVE_RESOLV_H #include +#ifdef HAVE_ARPA_NAMESER_COMPAT_H +#include +#endif #include +#endif +#include #include "sysdep_decls.h" #include "citadel.h" #include "domain.h" -#include "server.h" -#include "tools.h" #include "internet_addressing.h" /* - * get_smarthosts() checks the Internet configuration for "smarthost" + * get_hosts() checks the Internet configuration for various types of * entries and returns them in the same format as getmx() does -- fill the * buffer with a delimited list of hosts and return the number of hosts. + * + * This is used to fetch MX smarthosts, SpamAssassin hosts, etc. */ -int get_smarthosts(char *mxbuf) { +int get_hosts(char *mxbuf, char *rectype) { int config_lines; int i; - char buf[SIZ]; - char host[SIZ], type[SIZ]; + char buf[256]; + char host[256], type[256]; int total_smarthosts = 0; if (inetcfg == NULL) return(0); @@ -37,11 +48,11 @@ int get_smarthosts(char *mxbuf) { config_lines = num_tokens(inetcfg, '\n'); for (i=0; ipref; + pref2 = ((const struct mx *)mx2)->pref; - /* do the sort */ - for (a = num_mxrecs - 2; a >= 0; --a) { - for (b = 0; b <= a; ++b) { - if (mxrecs[b].pref > mxrecs[b+1].pref) { - - memcpy(&hold1, &mxrecs[b], sizeof(struct mx)); - memcpy(&hold2, &mxrecs[b+1], sizeof(struct mx)); - memcpy(&mxrecs[b], &hold2, sizeof(struct mx)); - memcpy(&mxrecs[b+1], &hold1, sizeof(struct mx)); - } - } + if (pref1 > pref2) { + return(1); + } + else if (pref1 < pref2) { + return(0); + } + else { + return(rand() % 2); } } - /* * getmx() * @@ -93,63 +98,58 @@ void sort_mxrecs(struct mx *mxrecs, int num_mxrecs) { * */ int getmx(char *mxbuf, char *dest) { - char answer[1024]; + +#ifdef HAVE_RESOLV_H + union { + u_char bytes[1024]; + HEADER header; + } answer; +#endif + int ret; unsigned char *startptr, *endptr, *ptr; char expanded_buf[1024]; unsigned short pref, type; int n = 0; - HEADER *hp; int qdcount; + Array *mxrecords = NULL; + struct mx mx; - struct mx *mxrecs = NULL; - int num_mxrecs = 0; - - /* If we're configured to send all mail to a smart-host, then our - * job here is really easy. - */ - n = get_smarthosts(mxbuf); - if (n > 0) return(n); - - /* - * No smart-host? Look up the best MX for a site. - */ - ret = res_query( - dest, - C_IN, T_MX, (unsigned char *)answer, sizeof(answer) ); + // If we're configured to send all mail to a smart-host, then our job here is really easy -- just return those. + n = get_hosts(mxbuf, "smarthost"); + if (n > 0) { + return(n); + } + + mxrecords = array_new(sizeof(struct mx)); + + // No smart-host? Look up the best MX for a site. Make a call to the resolver library. + ret = res_query(dest, C_IN, T_MX, (unsigned char *)answer.bytes, sizeof(answer)); if (ret < 0) { - mxrecs = mallok(sizeof(struct mx)); - mxrecs[0].pref = 0; - strcpy(mxrecs[0].host, dest); - num_mxrecs = 1; + mx.pref = 0; + strcpy(mx.host, dest); + array_append(mxrecords, &mx); } else { - - /* If we had to truncate, shrink the number to avoid fireworks */ - if (ret > sizeof(answer)) + if (ret > sizeof(answer)) { // If we had to truncate, shrink the number to avoid fireworks ret = sizeof(answer); + } + + startptr = &answer.bytes[0]; // start and end of buffer + endptr = &answer.bytes[ret]; + ptr = startptr + HFIXEDSZ; // advance past header - hp = (HEADER *)&answer[0]; - startptr = &answer[0]; /* start and end of buffer */ - endptr = &answer[ret]; - ptr = startptr + HFIXEDSZ; /* advance past header */ - - for (qdcount = ntohs(hp->qdcount); qdcount--; ptr += ret + QFIXEDSZ) { + for (qdcount = ntohs(answer.header.qdcount); qdcount--; ptr += ret + QFIXEDSZ) { if ((ret = dn_skipname(ptr, endptr)) < 0) { - lprintf(9, "dn_skipname error\n"); + syslog(LOG_DEBUG, "domain: dn_skipname error"); return(0); } } while(1) { memset(expanded_buf, 0, sizeof(expanded_buf)); - ret = dn_expand(startptr, - endptr, - ptr, - expanded_buf, - sizeof(expanded_buf) - ); + ret = dn_expand(startptr, endptr, ptr, expanded_buf, sizeof(expanded_buf)); if (ret < 0) break; ptr += ret; @@ -163,37 +163,30 @@ int getmx(char *mxbuf, char *dest) { else { GETSHORT(pref, ptr); - ret = dn_expand(startptr, - endptr, - ptr, - expanded_buf, - sizeof(expanded_buf) - ); + ret = dn_expand(startptr, endptr, ptr, expanded_buf, sizeof(expanded_buf)); ptr += ret; - ++num_mxrecs; - if (mxrecs == NULL) { - mxrecs = mallok(sizeof(struct mx)); - } - else { - mxrecs = reallok(mxrecs, - (sizeof(struct mx) * num_mxrecs) ); - } - - mxrecs[num_mxrecs - 1].pref = pref; - strcpy(mxrecs[num_mxrecs - 1].host, - expanded_buf); + mx.pref = pref; + strcpy(mx.host, expanded_buf); + array_append(mxrecords, &mx); } } } - sort_mxrecs(mxrecs, num_mxrecs); + // Sort the MX records by preference + if (array_len(mxrecords) > 1) { + array_sort(mxrecords, mx_compare_pref); + } + int num_mxrecs = array_len(mxrecords); strcpy(mxbuf, ""); for (n=0; nhost); strcat(mxbuf, "|"); } - phree(mxrecs); + array_free(mxrecords); + + // Append any fallback smart hosts we have configured. + num_mxrecs += get_hosts(&mxbuf[strlen(mxbuf)], "fallbackhost"); return(num_mxrecs); }