+SPF_dns_rr_t * spf_nxdomain = NULL;
+
+
+void
+spf_lib_version_report(FILE * fp)
+{
+int maj, min, patch;
+SPF_get_lib_version(&maj, &min, &patch);
+fprintf(fp, "Library version: spf2: Compile: %d.%d.%d\n",
+ SPF_LIB_VERSION_MAJOR, SPF_LIB_VERSION_MINOR, SPF_LIB_VERSION_PATCH);
+fprintf(fp, " Runtime: %d.%d.%d\n",
+ maj, min, patch);
+}
+
+
+
+static SPF_dns_rr_t *
+SPF_dns_exim_lookup(SPF_dns_server_t *spf_dns_server,
+ const char *domain, ns_type rr_type, int should_cache)
+{
+dns_answer * dnsa = store_get_dns_answer();
+dns_scan dnss;
+SPF_dns_rr_t * spfrr;
+unsigned found = 0;
+
+SPF_dns_rr_t srr = {
+ .domain = CS domain, /* query information */
+ .domain_buf_len = 0,
+ .rr_type = rr_type,
+
+ .rr_buf_len = 0, /* answer information */
+ .rr_buf_num = 0, /* no free of s */
+ .utc_ttl = 0,
+
+ .hook = NULL, /* misc information */
+ .source = spf_dns_server
+};
+int dns_rc;
+
+DEBUG(D_receive) debug_printf("SPF_dns_exim_lookup '%s'\n", domain);
+
+/* Shortcircuit SPF RR lookups by returning NO_DATA. They were obsoleted by
+RFC 6686/7208 years ago. see bug #1294 */
+
+if (rr_type == T_SPF)
+ {
+ HDEBUG(D_host_lookup) debug_printf("faking NO_DATA for SPF RR(99) lookup\n");
+ srr.herrno = NO_DATA;
+ SPF_dns_rr_dup(&spfrr, &srr);
+ return spfrr;
+ }
+
+switch (dns_rc = dns_lookup(dnsa, US domain, rr_type, NULL))
+ {
+ case DNS_SUCCEED: srr.herrno = NETDB_SUCCESS; break;
+ case DNS_AGAIN: srr.herrno = TRY_AGAIN; break;
+ case DNS_NOMATCH: srr.herrno = HOST_NOT_FOUND; break;
+ case DNS_NODATA: srr.herrno = NO_DATA; break;
+ case DNS_FAIL:
+ default: srr.herrno = NO_RECOVERY; break;
+ }
+
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
+ if (rr->type == rr_type) found++;
+
+if (found == 0)
+ {
+ SPF_dns_rr_dup(&spfrr, &srr);
+ return spfrr;
+ }
+
+srr.rr = store_malloc(sizeof(SPF_dns_rr_data_t) * found);
+
+found = 0;
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
+ if (rr->type == rr_type)
+ {
+ const uschar * s = rr->data;
+
+ srr.ttl = rr->ttl;
+ switch(rr_type)
+ {
+ case T_MX:
+ s += 2; /* skip the MX precedence field */
+ case T_PTR:
+ {
+ uschar * buf = store_malloc(256);
+ (void)dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, s,
+ (DN_EXPAND_ARG4_TYPE)buf, 256);
+ s = buf;
+ break;
+ }
+
+ case T_TXT:
+ {
+ gstring * g = NULL;
+ uschar chunk_len;
+
+ if (strncmpic(rr->data+1, US SPF_VER_STR, 6) != 0)
+ {
+ HDEBUG(D_host_lookup) debug_printf("not an spf record: %.*s\n",
+ (int) s[0], s+1);
+ continue;
+ }
+
+ for (int off = 0; off < rr->size; off += chunk_len)
+ {
+ if (!(chunk_len = s[off++])) break;
+ g = string_catn(g, s+off, chunk_len);
+ }
+ if (!g)
+ continue;
+ gstring_release_unused(g);
+ s = string_copy_malloc(string_from_gstring(g));
+ DEBUG(D_receive) debug_printf("SPF_dns_exim_lookup '%s'\n", s);
+ break;
+ }
+
+ case T_A:
+ case T_AAAA:
+ default:
+ {
+ uschar * buf = store_malloc(dnsa->answerlen + 1);
+ s = memcpy(buf, s, dnsa->answerlen + 1);
+ break;
+ }
+ }
+ srr.rr[found++] = (void *) s;
+ }
+
+/* Did we filter out all TXT RRs? Return NO_DATA instead of SUCCESS with
+empty ANSWER section. */
+
+if (!(srr.num_rr = found))
+ srr.herrno = NO_DATA;
+
+/* spfrr->rr must have been malloc()d for this */
+SPF_dns_rr_dup(&spfrr, &srr);
+return spfrr;
+}
+
+
+
+SPF_dns_server_t *
+SPF_dns_exim_new(int debug)
+{
+SPF_dns_server_t * spf_dns_server = store_malloc(sizeof(SPF_dns_server_t));
+
+DEBUG(D_receive) debug_printf("SPF_dns_exim_new\n");
+
+memset(spf_dns_server, 0, sizeof(SPF_dns_server_t));
+spf_dns_server->destroy = NULL;
+spf_dns_server->lookup = SPF_dns_exim_lookup;
+spf_dns_server->get_spf = NULL;
+spf_dns_server->get_exp = NULL;
+spf_dns_server->add_cache = NULL;
+spf_dns_server->layer_below = NULL;
+spf_dns_server->name = "exim";
+spf_dns_server->debug = debug;
+
+/* XXX This might have to return NO_DATA sometimes. */
+
+spf_nxdomain = SPF_dns_rr_new_init(spf_dns_server,
+ "", ns_t_any, 24 * 60 * 60, HOST_NOT_FOUND);
+if (!spf_nxdomain)
+ {
+ free(spf_dns_server);
+ return NULL;
+ }
+
+return spf_dns_server;
+}
+