/*
* call the dns process and have it try to translate a name
*/
static struct ndbtuple *dnsiplookup(char *host, struct ndbs *s)
{
char buf[Maxreply];
struct ndbtuple *t;
spinlock_unlock(&dblock);
/* save the name */
snprintf(buf, sizeof(buf), "%s", host);
if (strcmp(ipattr(buf), "ip") == 0)
t = dnsquery(mntpt, buf, "ptr");
else {
t = dnsquery(mntpt, buf, "ip");
/* special case: query ipv6 (AAAA dns RR) too */
if (ipv6lookups)
t = dnsip6lookup(mntpt, buf, t);
}
s->t = t;
if (t == NULL) {
snprintf(buf, sizeof(buf), "%r");
if (strstr(buf, "exist"))
werrstr("can't translate address: %s", buf);
else if (strstr(buf, "dns failure"))
werrstr("temporary problem: %s", buf);
}
spinlock_lock(&dblock);
return t;
}
/*
* use dns to resolve the mx request
*/
static int
mxlookup(DS *ds, char *domain)
{
int i, n, nmx;
Ndbtuple *t, *tmx, *tpref, *tip;
strcpy(domain, ds->host);
ds->netdir = "/net";
nmx = 0;
if((t = dnsquery(nil, ds->host, "mx")) != nil){
for(tmx=t; (tmx=ndbfindattr(tmx->entry, nil, "mx")) != nil && nmx<Nmx; ){
for(tpref=tmx->line; tpref != tmx; tpref=tpref->line){
if(strcmp(tpref->attr, "pref") == 0){
strncpy(mx[nmx].host, tmx->val, sizeof(mx[n].host)-1);
mx[nmx].pref = atoi(tpref->val);
nmx++;
break;
}
}
}
ndbfree(t);
}
/*
* no mx record? try name itself.
*/
/*
* BUG? If domain has no dots, then we used to look up ds->host
* but return domain instead of ds->host in the list. Now we return
* ds->host. What will this break?
*/
if(nmx == 0){
mx[0].pref = 1;
strncpy(mx[0].host, ds->host, sizeof(mx[0].host));
nmx++;
}
/*
* look up all ip addresses
*/
for(i = 0; i < nmx; i++){
if((t = dnsquery(nil, mx[i].host, "ip")) == nil)
goto no;
if((tip = ndbfindattr(t, nil, "ip")) == nil){
ndbfree(t);
goto no;
}
strncpy(mx[i].ip, tip->val, sizeof(mx[i].ip)-1);
ndbfree(t);
continue;
no:
/* remove mx[i] and go around again */
nmx--;
mx[i] = mx[nmx];
i--;
}
return nmx;
}
int
nbnameresolve(NbName nbname, uchar *ipaddr)
{
ulong r, ttl;
char name[NETPATHLEN];
NbName copy;
Ndbtuple *t;
/* for now, just use dns */
if (nbremotenametablefind(nbname, ipaddr)) {
//print("%B found in cache\n", nbname);
return 1;
}
if (nbnsfindname(nil, nbname, ipaddr, &ttl) == 0) {
nbremotenametableadd(nbname, ipaddr, ttl);
return 1;
}
nbnamecpy(copy, nbname);
copy[NbNameLen - 1] = 0;
nbmkstringfromname(name, sizeof(name), copy);
t = dnsquery("/net", name, "ip");
if (t == nil)
return 0;
r = parseip(ipaddr, t->line->val);
ndbfree(t);
return r != -1;
}
int send_request(char *domain, int port, char *url){
int sock;
struct sockaddr_in addr;
char ipaddr[20];
memset(ipaddr, 0, sizeof(ipaddr));
if (-1 == (sock = socket(AF_INET, SOCK_STREAM, 0))){
return -1;
}
dnsquery(domain, 80, ipaddr);
//fprintf(stderr, "domain=%s, ipaddr=%s\n", domain, ipaddr);
memset(&addr,0,sizeof(struct sockaddr_in));
addr.sin_family=AF_INET;
addr.sin_port=htons(port);
addr.sin_addr.s_addr=inet_addr(ipaddr);
if(connect(sock,(struct sockaddr *)&addr,sizeof(addr)))
{
printf("cannot connect to server\n");
close(sock);
return 1;
}
char *request = form_http_header("MagicWiFi", domain, url);
//printf("request=[%s]\n", request);
send(sock, request, strlen(request), 0);
free(request);
char response[4096];
memset(response, 0, sizeof(response));
int len= read(sock, response, 4096);
printf("response len=%d\n", len);
//fprintf(stderr, "response=[%s]\n", response);
//struct hostent *gethostbyname(const char *hostname);
close(sock);
if (strstr(response, "200 OK") || strstr(response, "302 Found")
|| strstr(response, "302 FOUND")
){
return 0;
}
return -1;
}
/*
* read (recipient, sender's DNS) pairs from /mail/lib/senders.
* Only allow mail to recipient from any of sender's IPs.
* A recipient not mentioned in the file is always permitted.
*/
static int
senderok(char *rcpt)
{
int mentioned = 0, matched = 0;
uchar dnsip[IPaddrlen];
Sender *snd;
Ndbtuple *nt, *next, *first;
rdsenders();
for (snd = sendlist; snd != nil; snd = snd->next) {
if (strcmp(rcpt, snd->rcpt) != 0)
continue;
/*
* see if this domain's ips match nci->rsys.
* if not, perhaps a later entry's domain will.
*/
mentioned = 1;
if (parseip(dnsip, snd->domain) != -1 &&
memcmp(rsysip, dnsip, IPaddrlen) == 0)
return 1;
/*
* NB: nt->line links form a circular list(!).
* we need to make one complete pass over it to free it all.
*/
first = nt = dnsquery(nci->root, snd->domain, "ip");
if (first == nil)
continue;
do {
if (strcmp(nt->attr, "ip") == 0 &&
parseip(dnsip, nt->val) != -1 &&
memcmp(rsysip, dnsip, IPaddrlen) == 0)
matched = 1;
next = nt->line;
free(nt);
nt = next;
} while (nt != first);
}
if (matched)
return 1;
else
return !mentioned;
}
static struct ndbtuple *dnsip6lookup(char *mntpt, char *buf, struct ndbtuple *t)
{
struct ndbtuple *t6, *tt;
t6 = dnsquery(mntpt, buf, "ipv6"); /* lookup AAAA dns RRs */
if (t6 == NULL)
return t;
/* convert ipv6 attr to ip */
for (tt = t6; tt != NULL; tt = tt->entry)
if (strcmp(tt->attr, "ipv6") == 0)
strlcpy(tt->attr, "ip", sizeof(tt->attr));
if (t == NULL)
return t6;
/* append t6 list to t list */
for (tt = t; tt->entry != NULL; tt = tt->entry)
;
tt->entry = t6;
return t;
}
