Commit | Line | Data |
---|---|---|
dc0d77d7 CE |
1 | #include "stralloc.h" |
2 | #include "byte.h" | |
3 | #include "uint16.h" | |
4 | #include "dns.h" | |
5 | ||
6 | static char *q = 0; | |
7 | ||
8 | int dns_mx_packet(stralloc *out,const char *buf,unsigned int len) | |
9 | { | |
10 | unsigned int pos; | |
11 | char header[12]; | |
12 | char pref[2]; | |
13 | uint16 numanswers; | |
14 | uint16 datalen; | |
15 | ||
16 | if (!stralloc_copys(out,"")) return -1; | |
17 | ||
18 | pos = dns_packet_copy(buf,len,0,header,12); if (!pos) return -1; | |
19 | uint16_unpack_big(header + 6,&numanswers); | |
20 | pos = dns_packet_skipname(buf,len,pos); if (!pos) return -1; | |
21 | pos += 4; | |
22 | ||
23 | while (numanswers--) { | |
24 | pos = dns_packet_skipname(buf,len,pos); if (!pos) return -1; | |
25 | pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) return -1; | |
26 | uint16_unpack_big(header + 8,&datalen); | |
27 | if (byte_equal(header,2,DNS_T_MX)) | |
28 | if (byte_equal(header + 2,2,DNS_C_IN)) { | |
29 | if (!dns_packet_copy(buf,len,pos,pref,2)) return -1; | |
30 | if (!dns_packet_getname(buf,len,pos + 2,&q)) return -1; | |
31 | if (!stralloc_catb(out,pref,2)) return -1; | |
32 | if (!dns_domain_todot_cat(out,q)) return -1; | |
33 | if (!stralloc_0(out)) return -1; | |
34 | } | |
35 | pos += datalen; | |
36 | } | |
37 | ||
38 | return 0; | |
39 | } | |
40 | ||
41 | int dns_mx(stralloc *out,const stralloc *fqdn) | |
42 | { | |
43 | if (!dns_domain_fromdot(&q,fqdn->s,fqdn->len)) return -1; | |
44 | if (dns_resolve(q,DNS_T_MX) == -1) return -1; | |
45 | if (dns_mx_packet(out,dns_resolve_tx.packet,dns_resolve_tx.packetlen) == -1) return -1; | |
46 | dns_transmit_free(&dns_resolve_tx); | |
47 | dns_domain_free(&q); | |
48 | return 0; | |
49 | } |