/*
Fallback to 'addr'
*/
void *_ruli_srv_answer_fallback_addr(ruli_srv_t *srv_qry)
{
ruli_host_t *fall_qry;
#ifdef RULI_SRV_DEBUG
{
char txt_dname_buf[RULI_LIMIT_DNAME_TEXT_BUFSZ];
int txt_dname_len;
int result;
result = ruli_dname_decode(txt_dname_buf, RULI_LIMIT_DNAME_TEXT_BUFSZ,
&txt_dname_len,
srv_qry->srv_domain, srv_qry->srv_domain_len);
assert(!result);
fprintf(stderr,
"DEBUG: %s: %s(): %d: address query: "
"domain=%s domain_len=%d fallback=%d\n",
__FILE__, __PRETTY_FUNCTION__, __LINE__,
txt_dname_buf, txt_dname_len,
!!(srv_qry->srv_options & RULI_RES_OPT_SRV_NOFALL));
}
#endif
/* Has the user disabled fallback query? */
if (srv_qry->srv_options & RULI_RES_OPT_SRV_NOFALL)
return query_done(srv_qry, RULI_SRV_CODE_OK);
/*
* Allocate space for fallback query
*/
fall_qry = (ruli_host_t *) \
ruli_malloc(sizeof(*fall_qry));
if (!fall_qry)
return query_done(srv_qry, RULI_SRV_CODE_FALL_OTHER);
/*
* Initialize fallback query arguments
*/
fall_qry->host_resolver = srv_qry->srv_resolver;
fall_qry->host_on_answer = on_fallback_answer;
fall_qry->host_on_answer_arg = srv_qry;
fall_qry->host_domain = srv_qry->srv_domain;
fall_qry->host_domain_len = srv_qry->srv_domain_len;
fall_qry->host_options = srv_qry->srv_options;
fall_qry->host_max_cname_depth = RULI_LIMIT_CNAME_DEPTH;
/*
* Submit fallback query
*/
if (ruli_host_query_submit(fall_qry)) {
ruli_free(fall_qry);
return query_done(srv_qry, RULI_SRV_CODE_FALL_OTHER);
}
/* Wait query answer */
return OOP_CONTINUE;
}
int main(int argc, const char *const *argv)
{
struct timeval *tv, tvbuf;
adns_query qu;
void *qun_v;
adns_answer *answer;
int r, maxfd;
fd_set readfds, writefds, exceptfds;
const char *arg;
ensure_adns_init();
while ((arg= *++argv)) process_optarg(arg,&argv,0);
if (!ov_pipe && !ads) usageerr("no domains given, and -f/--pipe not used; try --help");
for (;;)
{
for (;;)
{
qu= ov_asynch ? 0 : outstanding.head ? outstanding.head->qu : 0;
r= adns_check(ads,&qu,&answer,&qun_v);
if ((r == EAGAIN) || (r == EWOULDBLOCK)) break;
if (r == ESRCH)
{
if (!ov_pipe) goto x_quit;
else break;
}
assert(!r);
query_done(qun_v,answer);
}
maxfd= 0;
FD_ZERO(&readfds);
FD_ZERO(&writefds);
FD_ZERO(&exceptfds);
if (ov_pipe)
{
maxfd= 1;
FD_SET(0,&readfds);
}
tv= 0;
adns_beforeselect(ads, &maxfd, &readfds,&writefds,&exceptfds, &tv,&tvbuf,0);
ADNS_CLEAR_ERRNO;
r= select(maxfd, &readfds,&writefds,&exceptfds, tv);
ADNS_CAPTURE_ERRNO;
if (r == -1)
{
if (errno == EINTR) continue;
sysfail("select",errno);
}
adns_afterselect(ads, maxfd, &readfds,&writefds,&exceptfds, 0);
if (ov_pipe && FD_ISSET(0,&readfds)) read_stdin();
}
x_quit:
if (fclose(stdout)) outerr();
quitnow(rcode);
}
/*
finish fallback query
*/
static void *fall_query_done(ruli_srv_t *srv_qry, int srv_result_code,
ruli_host_t *fall_qry)
{
#ifdef RULI_SRV_DEBUG
fprintf(stderr,
"DEBUG: %s: %s(): %d: id=%d query_result=%s [%d]\n",
__FILE__, __PRETTY_FUNCTION__, __LINE__,
fall_qry->host_query.query_id,
srv_result_code ? "FAIL" : "SUCCESS",
srv_result_code);
#endif
f_query_done(fall_qry);
return query_done(srv_qry, srv_result_code);
}
/*
finish walk query
*/
static void *walk_query_done(walk_t *walk, int srv_result_code)
{
ruli_srv_t *srv_qry = walk->srv_query;
#ifdef RULI_SRV_DEBUG
fprintf(stderr,
"DEBUG: %s: %s(): %d: id=%d query_result=%s [%d]\n",
__FILE__, __PRETTY_FUNCTION__, __LINE__,
walk->walk_query.host_query.query_id,
srv_result_code ? "FAIL" : "SUCCESS",
srv_result_code);
#endif
w_query_done(walk);
return query_done(srv_qry, srv_result_code);
}
static void *on_srv_answer(ruli_res_query_t *qry, void *arg)
{
ruli_srv_t *srv_qry = (ruli_srv_t *) arg;
int result;
assert(qry->answer_code != RULI_SRV_CODE_VOID);
/*
* Underlying query failed?
*/
if (qry->answer_code == RULI_CODE_TIMEOUT)
return query_done(srv_qry, RULI_SRV_CODE_ALARM);
if (qry->answer_code)
return query_done(srv_qry, RULI_SRV_CODE_QUERY_FAILED);
#ifdef RULI_SRV_DEBUG
{
ruli_msg_header_t msg_hdr;
msg_hdr = qry->answer_header;
fprintf(stderr,
"DEBUG: on_srv_answer(): underlying query succeded: "
"id=%d rcode=%d qd=%d an=%d ns=%d ar=%d "
"answer_buf_size=%d answer_msg_len=%d\n",
msg_hdr.id, msg_hdr.rcode,
msg_hdr.qdcount, msg_hdr.ancount,
msg_hdr.nscount, msg_hdr.arcount,
qry->answer_buf_size, qry->answer_msg_len);
}
#endif
/*
* Parse answer for SRV records
*/
assert(sizeof(ruli_uint8_t) == sizeof(char));
result = ruli_parse_message(&srv_qry->parse, &qry->answer_header,
(ruli_uint8_t *) qry->answer_buf,
qry->answer_msg_len);
if (result)
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
/*
* Check reply code and answer count
*/
if ((qry->answer_header.rcode != RULI_RCODE_NOERROR) ||
(qry->answer_header.ancount < 1)) {
#ifdef RULI_SRV_DEBUG
fprintf(stderr,
"DEBUG: on_srv_answer(): SRV query failed\n");
#endif
/* Fallback query */
return srv_qry->fallback(srv_qry);
}
/*
* NOERROR && (ancount > 0)
*/
assert(qry->answer_header.rcode == RULI_RCODE_NOERROR);
assert(qry->answer_header.ancount > 0);
/*
* Processing of SRV answer:
*
* Step 1/6: One SRV RR with target == '.' ?
* Step 2/6: Parse rdata portion of all SRV RRs
* Step 3/6: Sort SRV RRs by priority
* Step 4/6: Select SRV RRs by random weighted order
* Step 5/6: Build list of srv answers by inspecting additional section
* Step 6/6: Launch queries to fill missing addresses, if any
*/
/*
* Step 1/6: One SRV RR with target == '.' ?
*/
if (qry->answer_header.ancount == 1) {
ruli_list_t *an_list = &srv_qry->parse.answer_list;
if (ruli_list_size(an_list) == 1) {
ruli_rr_t *rr = (ruli_rr_t *) ruli_list_top(an_list);
if (rr->qclass == RULI_RR_CLASS_IN) {
if (rr->type == RULI_RR_TYPE_SRV) {
ruli_srv_rdata_t srv_rdata;
if (ruli_parse_rr_srv(&srv_rdata, rr->rdata, rr->rdlength))
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
/* target == '.' ? */
if (*srv_rdata.target == '\0') {
/* Sanity test */
if (srv_rdata.target_len != 1)
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
/*
* ruli_srv.c: target=='.': Owner match?
*/
assert(sizeof(ruli_uint8_t) == sizeof(char));
#ifdef RULI_SRV_DEBUG
show_dname("on_srv_answer(): target=='.': qdomain",
(const char *) qry->full_dname, qry->full_dname_len);
#endif
if (ruli_dname_compare(rr->owner,
(ruli_uint8_t *) qry->answer_buf,
qry->answer_msg_len,
(ruli_uint8_t *) qry->full_dname,
qry->full_dname_len))
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
return query_done(srv_qry, RULI_SRV_CODE_UNAVAILABLE);
}
}
}
}
} /* One SRV RR with target == '.' ? */
/*
* Step 2/6: Parse rdata portion of all SRV RRs
*/
{
ruli_list_t *an_list = &srv_qry->parse.answer_list;
int an_list_size = ruli_list_size(an_list);
int i;
for (i = 0; i < an_list_size; ++i) {
ruli_rr_t *rr = (ruli_rr_t *) ruli_list_get(an_list, i);
ruli_srv_rdata_t *srv_rdata;
if (rr->qclass != RULI_RR_CLASS_IN)
continue;
if (rr->type != RULI_RR_TYPE_SRV)
continue;
#ifdef RULI_SRV_DEBUG
fprintf(stderr,
"DEBUG: on_srv_answer(): considering SRV-RR owner: %d of %d\n",
(i + 1), an_list_size);
#endif
if (ruli_dname_compare(rr->owner,
(ruli_uint8_t *) qry->answer_buf,
qry->answer_msg_len,
(ruli_uint8_t *) qry->full_dname,
qry->full_dname_len))
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
#ifdef RULI_SRV_DEBUG
fprintf(stderr,
"DEBUG: on_srv_answer(): SRV-RR owner OK: %d of %d\n",
(i + 1), an_list_size);
#endif
srv_rdata = (ruli_srv_rdata_t *) ruli_malloc(sizeof(ruli_srv_rdata_t));
if (!srv_rdata)
return query_done(srv_qry, RULI_SRV_CODE_MALLOC);
if (ruli_list_push(&srv_qry->rr_srv_list, srv_rdata)) {
ruli_free(srv_rdata);
return query_done(srv_qry, RULI_SRV_CODE_LIST);
}
if (ruli_parse_rr_srv(srv_rdata, rr->rdata, rr->rdlength))
return query_done(srv_qry, RULI_SRV_CODE_PARSE_FAILED);
}
}
#ifdef RULI_SRV_DEBUG
{
int i;
ruli_list_t *list = &srv_qry->rr_srv_list;
fflush(stdout);
for (i = 0; i < ruli_list_size(list); ++i) {
ruli_srv_rdata_t *srv_rdata = \
(ruli_srv_rdata_t *) ruli_list_get(list, i);
fflush(stderr);
fprintf(stderr,
"DEBUG: on_srv_answer(): SRV RR: "
"priority=%d weight=%d port=%d\n",
srv_rdata->priority, srv_rdata->weight, srv_rdata->port);
fflush(stderr);
}
}
#endif
/*
* Step 3/6: Sort SRV RRs by priority
*/
{
ruli_list_t *src_list = &srv_qry->rr_srv_list;
int src_list_size = ruli_list_size(src_list);
int j;
/*
* Handle every RR based on priority (higher priority first)
*/
for (j = 0; j < src_list_size; ++j) {
ruli_srv_rdata_t *srv_rdata = \
(ruli_srv_rdata_t *) ruli_list_get(src_list, j);
ruli_list_t *dst_list = &srv_qry->pri_srv_list;
int dst_list_size = ruli_list_size(dst_list);
int i;
assert(srv_rdata);
/*
* Find a lower-or-equal priority
*/
for (i = 0; i < dst_list_size; ++i) {
ruli_srv_rdata_t *rd = (ruli_srv_rdata_t *) ruli_list_get(dst_list, i);
if (srv_rdata->priority < rd->priority)
continue;
/*
* For this priority, put 0-weight-elements at tail
*/
if (srv_rdata->weight == 0) {
/*
* Find begin of next priority and insert there
*/
for (; i < dst_list_size; ++i) {
ruli_srv_rdata_t *s_rd = \
(ruli_srv_rdata_t *) ruli_list_get(dst_list, i);
if (srv_rdata->priority != s_rd->priority)
break;
} /* for */
if (i == dst_list_size)
break; /* Insert at tail (of this priority) */
}
if (ruli_list_insert_at(dst_list, i, srv_rdata))
return query_done(srv_qry, RULI_SRV_CODE_LIST);
srv_rdata = 0; /* mark as handled */
break;
} /* for */
/* If not handled yet, insert at tail */
if (srv_rdata)
if (ruli_list_push(dst_list, srv_rdata))
return query_done(srv_qry, RULI_SRV_CODE_LIST);
} /* while */
}
#ifdef RULI_SRV_DEBUG
{
int i;
ruli_list_t *list = &srv_qry->pri_srv_list;
fflush(stdout);
for (i = 0; i < ruli_list_size(list); ++i) {
ruli_srv_rdata_t *srv_rdata = \
(ruli_srv_rdata_t *) ruli_list_get(list, i);
fflush(stderr);
fprintf(stderr,
"DEBUG: on_srv_answer(): priority SRV RR: "
"priority=%d weight=%d port=%d\n",
srv_rdata->priority, srv_rdata->weight, srv_rdata->port);
fflush(stderr);
}
}
#endif
/*
* Step 4/6: Select SRV RRs by random weighted order
*/
{
ruli_list_t *src_list = &srv_qry->pri_srv_list;
ruli_list_t *dst_list = &srv_qry->wei_srv_list;
/*
* Iterate over every priority
*/
for (;;) {
int src_list_size = ruli_list_size(src_list);
ruli_uint16_t curr_priority;
int priority_weight_sum;
int curr;
int i;
int rnd;
int run_sum;
ruli_srv_rdata_t *srv_rd;
if (src_list_size < 1)
break;
/*
* Get current priority
*/
curr = src_list_size - 1;
srv_rd = (ruli_srv_rdata_t *) ruli_list_get(src_list, curr);
curr_priority = srv_rd->priority;
/*
* Accumulate weight sum for priority
*/
priority_weight_sum = 0;
for (i = curr; i >= 0; --i) {
ruli_srv_rdata_t *rd = (ruli_srv_rdata_t *) ruli_list_get(src_list, i);
if (curr_priority != rd->priority)
break;
priority_weight_sum += rd->weight;
} /* for */
/*
* Pick random number: 0..priority_weight_sum
*/
rnd = ruli_rand_next(&srv_qry->srv_resolver->rand_ctx,
0, priority_weight_sum);
/*
* Select least running sum
*/
run_sum = 0;
for (i = curr; ; --i) {
ruli_srv_rdata_t *rd;
assert(i >= 0);
rd = (ruli_srv_rdata_t *) ruli_list_get(src_list, i);
run_sum += rd->weight;
if (run_sum < rnd)
continue;
/*
* Move from src_list to dst_list
* (Both lists are only referential)
*/
ruli_list_shift_at(src_list, i);
if (ruli_list_push(dst_list, rd))
return query_done(srv_qry, RULI_SRV_CODE_LIST);
break;
} /* for */
} /* for */
}
#ifdef RULI_SRV_DEBUG
{
int i;
ruli_list_t *list = &srv_qry->wei_srv_list;
fflush(stdout);
for (i = 0; i < ruli_list_size(list); ++i) {
ruli_srv_rdata_t *srv_rdata = \
(ruli_srv_rdata_t *) ruli_list_get(list, i);
fflush(stderr);
fprintf(stderr,
"DEBUG: on_srv_answer(): weight SRV RR: "
"priority=%d weight=%d port=%d\n",
srv_rdata->priority, srv_rdata->weight, srv_rdata->port);
fflush(stderr);
}
}
#endif
/*
* Step 5/6: Build list of srv answers by inspecting additional section
*/
{
ruli_list_t *src_list = &srv_qry->wei_srv_list;
ruli_list_t *dst_list = &srv_qry->answer_srv_list;
int src_list_size = ruli_list_size(src_list);
int i;
assert(ruli_list_size(dst_list) == 0);
#ifdef RULI_SRV_DEBUG
{
fflush(stdout);
fprintf(stderr,
"DEBUG: %s: %s(): %d: "
"BEFORE addit inspection: "
"srv_rr_list_size=%d srv_answer_list_size=%d\n",
__FILE__, __PRETTY_FUNCTION__, __LINE__,
src_list_size, ruli_list_size(&srv_qry->answer_srv_list));
fflush(stderr);
}
#endif
/*
* Build answer records inspecting additional section
*/
/* Scan all targets */
for (i = 0; i < src_list_size; ++i) {
ruli_srv_rdata_t *rd = (ruli_srv_rdata_t *) ruli_list_get(src_list, i);
ruli_srv_entry_t *srv_entry;
/* Create SRV entry and append it to list */
srv_entry =_ruli_srv_list_new_entry(dst_list,
(const char *) rd->target,
rd->target_len,
rd->priority,
rd->weight,
rd->port);
if (!srv_entry)
return query_done(srv_qry, RULI_SRV_CODE_MALLOC);
/*
* Look up target address(es) in additional section
*/
{
ruli_list_t *ad_list = &srv_qry->parse.additional_list;
int ad_list_size = ruli_list_size(ad_list);
int j;
/* Scan additional section */
for (j = 0; j < ad_list_size; ++j) {
ruli_rr_t *rr = (ruli_rr_t *) ruli_list_get(ad_list, j);
ruli_addr_t *addr;
if (rr->qclass != RULI_RR_CLASS_IN)
continue;
if (!ruli_rr_type_is_address(srv_qry->srv_options, rr->type))
continue;
/* Compare SRV target against additional record owner */
if (ruli_dname_compare(rr->owner,
(ruli_uint8_t *) qry->answer_buf,
qry->answer_msg_len,
(ruli_uint8_t *) srv_entry->target,
srv_entry->target_len))
continue;
/* Allocate space for address */
addr = (ruli_addr_t *) ruli_malloc(sizeof(*addr));
if (!addr)
return query_done(srv_qry, RULI_SRV_CODE_MALLOC);
/* Save space */
if (ruli_list_push(&srv_entry->addr_list, addr)) {
ruli_free(addr);
return query_done(srv_qry, RULI_SRV_CODE_LIST);
}
/* Write address into space */
ruli_parse_addr_rr(addr, rr, srv_qry->srv_options);
} /* for */
}
} /* for */
#ifdef RULI_SRV_DEBUG
{
fflush(stdout);
fprintf(stderr,
"DEBUG: %s: %s(): %d: "
"AFTER addit inspection: "
"srv_rr_list_size=%d srv_answer_list_size=%d\n",
__FILE__, __PRETTY_FUNCTION__, __LINE__,
src_list_size, ruli_list_size(&srv_qry->answer_srv_list));
fflush(stderr);
}
#endif
assert(ruli_list_size(dst_list) == src_list_size);
} /* Build list of srv answers by inspecting additional section */
#ifdef RULI_SRV_DEBUG
{
int i;
ruli_list_t *list = &srv_qry->answer_srv_list;
fflush(stdout);
for (i = 0; i < ruli_list_size(list); ++i) {
ruli_srv_entry_t *srv_entry = \
(ruli_srv_entry_t *) ruli_list_get(list, i);
fprintf(stderr,
"DEBUG: on_srv_answer(): answer SRV RR: "
"priority=%d weight=%d port=%d\n",
srv_entry->priority, srv_entry->weight, srv_entry->port);
}
fflush(stderr);
}
#endif
/*
* Step 6/6: Launch queries to fill missing addresses, if any
*/
assert(srv_qry->under.walk_index == -1);
srv_qry->under.walk_index = 0;
return _ruli_srv_answer_walk(srv_qry);
}
/*
Search missing addresses for targets.
We make serialized queries so we don't need
to keep more than one query reference (walk_query).
*/
void *_ruli_srv_answer_walk(ruli_srv_t *srv_qry)
{
ruli_list_t *srv_list = &srv_qry->answer_srv_list;
int srv_list_size = ruli_list_size(srv_list);
/* Have the user disabled walk query? */
if (srv_qry->srv_options & RULI_RES_OPT_SRV_NOWALK)
return query_done(srv_qry, RULI_SRV_CODE_OK);
/*
* Scan SRV answer targets, considering address lists
*/
for (; srv_qry->under.walk_index < srv_list_size;
++srv_qry->under.walk_index) {
ruli_srv_entry_t *entry = \
(ruli_srv_entry_t *) ruli_list_get(srv_list,
srv_qry->under.walk_index);
ruli_list_t *addr_list = &entry->addr_list;
walk_t *walk_qry;
/* If this target already has address(es), skip it */
if (find_addr(addr_list, srv_qry->srv_options))
continue;
#ifdef RULI_SRV_DEBUG
{
char target_txt[RULI_LIMIT_DNAME_TEXT_BUFSZ];
int target_txt_len;
int result;
result = ruli_dname_decode(target_txt, RULI_LIMIT_DNAME_TEXT_BUFSZ,
&target_txt_len, entry->target,
entry->target_len);
assert(!result);
fprintf(stderr,
"DEBUG: _ruli_srv_answer_walk(): "
"missing target=%s walk_index=%d\n",
target_txt, srv_qry->under.walk_index);
}
#endif
/*
* Allocate space for auxiliary walk query
*/
walk_qry = \
(walk_t *) ruli_malloc(sizeof(*walk_qry));
if (!walk_qry)
return query_done(srv_qry, RULI_SRV_CODE_WALK_OTHER);
walk_qry->srv_query = srv_qry;
/*
* Initialize walk query arguments
*/
walk_qry->walk_query.host_resolver = srv_qry->srv_resolver;
walk_qry->walk_query.host_on_answer = on_walk_answer;
walk_qry->walk_query.host_on_answer_arg = walk_qry;
walk_qry->walk_query.host_domain = entry->target;
walk_qry->walk_query.host_domain_len = entry->target_len;
walk_qry->walk_query.host_options = srv_qry->srv_options;
/* RFC 2782 states CNAME aren't valid SRV targets */
walk_qry->walk_query.host_max_cname_depth =
(srv_qry->srv_options & RULI_RES_OPT_SRV_CNAME) ?
RULI_LIMIT_CNAME_DEPTH : 0;
/*
* Submit walk query
*/
if (ruli_host_query_submit(&walk_qry->walk_query)) {
ruli_free(walk_qry);
return query_done(srv_qry, RULI_SRV_CODE_WALK_QUERY);
}
/* Wait answer */
return OOP_CONTINUE;
} /* for */
/*
* All targets scanned, we're done
*/
return query_done(srv_qry, RULI_SRV_CODE_OK);
}
