Gitweb:
https://git.exim.org/exim.git/commitdiff/4a3709fb2cfb1ec26ac60bcdb8bbc078d3377ddc
Commit: 4a3709fb2cfb1ec26ac60bcdb8bbc078d3377ddc
Parent: 847a015ae17b3fa66154088009803636f95b2c6f
Author: Wolfgang Breyha <wbreyha@???>
AuthorDate: Fri Dec 20 14:01:23 2019 +0000
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Sat Dec 21 20:31:03 2019 +0000
SPF: only require "v=spf1" on TXT DNS records during lookups. Bug 2499
---
src/src/spf.c | 60 +++++++++++++++++++++++++++++++++++++++++++----------------
1 file changed, 44 insertions(+), 16 deletions(-)
diff --git a/src/src/spf.c b/src/src/spf.c
index 1955b5d..b7041d3 100644
--- a/src/src/spf.c
+++ b/src/src/spf.c
@@ -43,17 +43,15 @@ dns_answer * dnsa = store_get_dns_answer();
dns_scan dnss;
SPF_dns_rr_t * spfrr;
-DEBUG(D_receive) debug_printf("SPF_dns_exim_lookup\n");
+DEBUG(D_receive) debug_printf("SPF_dns_exim_lookup '%s'\n", domain);
if (dns_lookup(dnsa, US domain, rr_type, NULL) == DNS_SUCCEED)
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
- && Ustrncmp(rr->data+1, "v=spf1", 6) == 0)
+ && (rr_type != T_TXT || Ustrncmp(rr->data+1, "v=spf1", 6) == 0))
{
- gstring * g = NULL;
- uschar chunk_len;
- uschar * s;
+ const uschar * s = rr->data;
SPF_dns_rr_t srr = {
.domain = CS rr->name, /* query information */
.domain_buf_len = DNS_MAXNAME,
@@ -71,19 +69,49 @@ if (dns_lookup(dnsa, US domain, rr_type, NULL) == DNS_SUCCEED)
.source = spf_dns_server
};
- for (int off = 0; off < rr->size; off += chunk_len)
+ switch(rr_type)
{
- chunk_len = (rr->data)[off++];
- g = string_catn(g, US ((rr->data)+off), chunk_len);
+ 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;
+ 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)
+ {
+ HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an "
+ "empty name: treated as non-existent host name\n");
+ continue;
+ }
+ gstring_release_unused(g);
+ s = string_copy_malloc(string_from_gstring(g));
+ break;
+ }
+
+ case T_A:
+ case T_AAAA:
+ default:
+ {
+ uschar * buf = store_malloc(dnsa->answerlen + 1);
+ s = memcpy(buf, s, dnsa->answerlen + 1);
+ break;
+ }
}
- if (!g)
- {
- HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an "
- "empty name: treated as non-existent host name\n");
- 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);
srr.rr = (void *) &s;
/* spfrr->rr must have been malloc()d for this */
