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resolved: add API for resolving specific RRs

This commit is contained in:
Lennart Poettering 2014-07-30 19:23:27 +02:00
parent 6f4d55a8ae
commit 2d4c5cbc0e
5 changed files with 489 additions and 89 deletions

View File

@ -4848,7 +4848,17 @@ lib_LTLIBRARIES += \
libnss_resolve.la
systemd_resolve_host_SOURCES = \
src/resolve-host/resolve-host.c
src/resolve-host/resolve-host.c \
src/resolve/resolved-dns-packet.c \
src/resolve/resolved-dns-packet.h \
src/resolve/resolved-dns-rr.c \
src/resolve/resolved-dns-rr.h \
src/resolve/resolved-dns-answer.c \
src/resolve/resolved-dns-answer.h \
src/resolve/resolved-dns-question.c \
src/resolve/resolved-dns-question.h \
src/resolve/resolved-dns-domain.c \
src/resolve/resolved-dns-domain.h
systemd_resolve_host_LDADD = \
libsystemd-internal.la \

View File

@ -31,10 +31,14 @@
#include "af-list.h"
#include "build.h"
#include "resolved-dns-packet.h"
#define DNS_CALL_TIMEOUT_USEC (45*USEC_PER_SEC)
static int arg_family = AF_UNSPEC;
static int arg_ifindex = 0;
static uint16_t arg_type = 0;
static uint16_t arg_class = 0;
static int resolve_host(sd_bus *bus, const char *name) {
@ -286,6 +290,103 @@ static int parse_address(const char *s, int *family, union in_addr_union *addres
return 0;
}
static int resolve_record(sd_bus *bus, const char *name) {
_cleanup_bus_message_unref_ sd_bus_message *req = NULL, *reply = NULL;
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
unsigned n = 0;
int r;
assert(name);
log_debug("Resolving %s %s %s.", name, dns_class_to_string(arg_class), dns_type_to_string(arg_type));
r = sd_bus_message_new_method_call(
bus,
&req,
"org.freedesktop.resolve1",
"/org/freedesktop/resolve1",
"org.freedesktop.resolve1.Manager",
"ResolveRecord");
if (r < 0)
return bus_log_create_error(r);
r = sd_bus_message_set_auto_start(req, false);
if (r < 0)
return bus_log_create_error(r);
r = sd_bus_message_append(req, "sqq", name, arg_class, arg_type);
if (r < 0)
return bus_log_create_error(r);
r = sd_bus_call(bus, req, DNS_CALL_TIMEOUT_USEC, &error, &reply);
if (r < 0) {
log_error("%s: resolve call failed: %s", name, bus_error_message(&error, r));
return r;
}
r = sd_bus_message_enter_container(reply, 'a', "(qqay)");
if (r < 0)
return bus_log_parse_error(r);
while ((r = sd_bus_message_enter_container(reply, 'r', "qqay")) > 0) {
_cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL;
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
_cleanup_free_ char *s = NULL;
uint16_t c, t;
const void *d;
size_t l;
r = sd_bus_message_read(reply, "qq", &c, &t);
if (r < 0)
return bus_log_parse_error(r);
r = sd_bus_message_read_array(reply, 'y', &d, &l);
if (r < 0)
return bus_log_parse_error(r);
r = sd_bus_message_exit_container(reply);
if (r < 0)
return bus_log_parse_error(r);
r = dns_packet_new(&p, DNS_PROTOCOL_DNS, 0);
if (r < 0)
return log_oom();
r = dns_packet_append_blob(p, d, l, NULL);
if (r < 0)
return log_oom();
r = dns_packet_read_rr(p, &rr, NULL);
if (r < 0) {
log_error("Failed to parse RR.");
return r;
}
r = dns_resource_record_to_string(rr, &s);
if (r < 0) {
log_error("Failed to format RR.");
return r;
}
printf("%s\n", s);
n++;
}
if (r < 0)
return bus_log_parse_error(r);
r = sd_bus_message_exit_container(reply);
if (r < 0)
return bus_log_parse_error(r);
if (n == 0) {
log_error("%s: no records found", name);
return -ESRCH;
}
return 0;
}
static void help(void) {
printf("%s [OPTIONS...]\n\n"
"Resolve IPv4 or IPv6 addresses.\n\n"
@ -294,6 +395,8 @@ static void help(void) {
" -4 Resolve IPv4 addresses\n"
" -6 Resolve IPv6 addresses\n"
" -i INTERFACE Filter by interface\n"
" -t --type=TYPE Query RR with DNS type\n"
" -c --class=CLASS Query RR with DNS class\n"
, program_invocation_short_name);
}
@ -305,15 +408,17 @@ static int parse_argv(int argc, char *argv[]) {
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "type", no_argument, NULL, 't' },
{ "class", no_argument, NULL, 'c' },
{}
};
int c;
int c, r;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "h46i:", options, NULL)) >= 0) {
while ((c = getopt_long(argc, argv, "h46i:t:c:", options, NULL)) >= 0) {
switch(c) {
case 'h':
@ -337,7 +442,23 @@ static int parse_argv(int argc, char *argv[]) {
arg_ifindex = if_nametoindex(optarg);
if (arg_ifindex <= 0) {
log_error("Unknown interfaces %s: %m", optarg);
return -EINVAL;
return -errno;
}
break;
case 't':
r = dns_type_from_string(optarg, &arg_type);
if (r < 0) {
log_error("Failed to parse RR record type %s", optarg);
return r;
}
break;
case 'c':
r = dns_class_from_string(optarg, &arg_class);
if (r < 0) {
log_error("Failed to parse RR record class %s", optarg);
return r;
}
break;
@ -349,6 +470,14 @@ static int parse_argv(int argc, char *argv[]) {
}
}
if (arg_type == 0 && arg_class != 0) {
log_error("--class= may only be used in conjunction with --type=");
return -EINVAL;
}
if (arg_type != 0 && arg_class == 0)
arg_class = DNS_CLASS_IN;
return 1 /* work to do */;
}
@ -379,11 +508,15 @@ int main(int argc, char **argv) {
int family, ifindex, k;
union in_addr_union a;
k = parse_address(argv[optind], &family, &a, &ifindex);
if (k >= 0)
k = resolve_address(bus, family, &a, ifindex);
else
k = resolve_host(bus, argv[optind]);
if (arg_type != 0)
k = resolve_record(bus, argv[optind]);
else {
k = parse_address(argv[optind], &family, &a, &ifindex);
if (k >= 0)
k = resolve_address(bus, family, &a, ifindex);
else
k = resolve_host(bus, argv[optind]);
}
if (r == 0)
r = k;

View File

@ -157,13 +157,13 @@ static void bus_method_resolve_hostname_complete(DnsQuery *q) {
for (i = 0; i < answer->n_rrs; i++) {
r = dns_question_matches_rr(q->question, answer->rrs[i]);
if (r < 0)
goto parse_fail;
goto finish;
if (r == 0) {
/* Hmm, if this is not an address record,
maybe it's a cname? If so, remember this */
r = dns_question_matches_cname(q->question, answer->rrs[i]);
if (r < 0)
goto parse_fail;
goto finish;
if (r > 0)
cname = dns_resource_record_ref(answer->rrs[i]);
@ -204,7 +204,7 @@ static void bus_method_resolve_hostname_complete(DnsQuery *q) {
for (i = 0; i < answer->n_rrs; i++) {
r = dns_question_matches_rr(q->question, answer->rrs[i]);
if (r < 0)
goto parse_fail;
goto finish;
if (r == 0)
continue;
@ -230,6 +230,7 @@ static void bus_method_resolve_hostname_complete(DnsQuery *q) {
r = sd_bus_reply_method_errno(q->request, -r, NULL);
goto finish;
}
return;
}
}
@ -245,14 +246,12 @@ static void bus_method_resolve_hostname_complete(DnsQuery *q) {
goto finish;
r = sd_bus_send(q->manager->bus, reply, NULL);
goto finish;
parse_fail:
r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_INVALID_REPLY, "Received invalid reply");
finish:
if (r < 0)
log_error("Failed to send bus reply: %s", strerror(-r));
if (r < 0) {
log_error("Failed to send hostname reply: %s", strerror(-r));
sd_bus_reply_method_errno(q->request, -r, NULL);
}
dns_query_free(q);
}
@ -356,7 +355,7 @@ static void bus_method_resolve_address_complete(DnsQuery *q) {
for (i = 0; i < answer->n_rrs; i++) {
r = dns_question_matches_rr(q->question, answer->rrs[i]);
if (r < 0)
goto parse_fail;
goto finish;
if (r == 0)
continue;
@ -382,14 +381,12 @@ static void bus_method_resolve_address_complete(DnsQuery *q) {
goto finish;
r = sd_bus_send(q->manager->bus, reply, NULL);
goto finish;
parse_fail:
r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_INVALID_REPLY, "Received invalid reply");
finish:
if (r < 0)
log_error("Failed to send bus reply: %s", strerror(-r));
if (r < 0) {
log_error("Failed to send address reply: %s", strerror(-r));
sd_bus_reply_method_errno(q->request, -r, NULL);
}
dns_query_free(q);
}
@ -469,10 +466,144 @@ static int bus_method_resolve_address(sd_bus *bus, sd_bus_message *message, void
return 1;
}
static void bus_method_resolve_record_complete(DnsQuery *q) {
_cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
_cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL;
unsigned added = 0, i;
int r;
assert(q);
if (q->state != DNS_QUERY_SUCCESS) {
r = reply_query_state(q);
goto finish;
}
r = sd_bus_message_new_method_return(q->request, &reply);
if (r < 0)
goto finish;
r = sd_bus_message_open_container(reply, 'a', "(qqay)");
if (r < 0)
goto finish;
if (q->answer) {
answer = dns_answer_ref(q->answer);
for (i = 0; i < answer->n_rrs; i++) {
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
size_t start;
r = dns_question_matches_rr(q->question, answer->rrs[i]);
if (r < 0)
goto finish;
if (r == 0)
continue;
r = dns_packet_new(&p, DNS_PROTOCOL_DNS, 0);
if (r < 0)
goto finish;
r = dns_packet_append_rr(p, answer->rrs[i], &start);
if (r < 0)
goto finish;
r = sd_bus_message_open_container(reply, 'r', "qqay");
if (r < 0)
goto finish;
r = sd_bus_message_append(reply, "qq", answer->rrs[i]->key->class, answer->rrs[i]->key->type);
if (r < 0)
goto finish;
r = sd_bus_message_append_array(reply, 'y', DNS_PACKET_DATA(p) + start, p->size - start);
if (r < 0)
goto finish;
r = sd_bus_message_close_container(reply);
if (r < 0)
goto finish;
added ++;
}
}
if (added <= 0) {
r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "Name '%s' does not have any RR of the requested type", q->request_hostname);
goto finish;
}
r = sd_bus_message_close_container(reply);
if (r < 0)
goto finish;
r = sd_bus_send(q->manager->bus, reply, NULL);
finish:
if (r < 0) {
log_error("Failed to send record reply: %s", strerror(-r));
sd_bus_reply_method_errno(q->request, -r, NULL);
}
dns_query_free(q);
}
static int bus_method_resolve_record(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
_cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL;
_cleanup_(dns_question_unrefp) DnsQuestion *question = NULL;
_cleanup_free_ char *reverse = NULL;
Manager *m = userdata;
DnsQuery *q;
int r;
uint16_t class, type;
const char *name;
assert(bus);
assert(message);
assert(m);
r = sd_bus_message_read(message, "sqq", &name, &class, &type);
if (r < 0)
return r;
question = dns_question_new(1);
if (!question)
return -ENOMEM;
key = dns_resource_key_new(class, type, name);
if (!key)
return -ENOMEM;
r = dns_question_add(question, key);
if (r < 0)
return r;
r = dns_query_new(m, &q, question);
if (r < 0)
return r;
q->request = sd_bus_message_ref(message);
q->request_hostname = name;
q->complete = bus_method_resolve_record_complete;
r = dns_query_go(q);
if (r < 0) {
dns_query_free(q);
if (r == -ESRCH)
sd_bus_error_setf(error, BUS_ERROR_NO_NAME_SERVERS, "No appropriate name servers or networks for name found");
return r;
}
return 1;
}
static const sd_bus_vtable resolve_vtable[] = {
SD_BUS_VTABLE_START(0),
SD_BUS_METHOD("ResolveHostname", "si", "a(iayi)s", bus_method_resolve_hostname, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ResolveAddress", "iayi", "as", bus_method_resolve_address, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("ResolveRecord", "sqq", "a(qqay)", bus_method_resolve_record, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_VTABLE_END,
};

View File

@ -159,6 +159,31 @@ int dns_resource_key_compare_func(const void *a, const void *b) {
return 0;
}
int dns_resource_key_to_string(const DnsResourceKey *key, char **ret) {
char cbuf[DECIMAL_STR_MAX(uint16_t)], tbuf[DECIMAL_STR_MAX(uint16_t)];
const char *c, *t;
char *s;
c = dns_class_to_string(key->class);
if (!c) {
sprintf(cbuf, "%i", key->class);
c = cbuf;
}
t = dns_type_to_string(key->type);
if (!t){
sprintf(tbuf, "%i", key->type);
t = tbuf;
}
s = strjoin(DNS_RESOURCE_KEY_NAME(key), " ", c, " ", t, NULL);
if (!s)
return -ENOMEM;
*ret = s;
return 0;
}
DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key) {
DnsResourceRecord *rr;
@ -267,16 +292,24 @@ int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecor
if (r <= 0)
return r;
if (IN_SET(a->key->type, DNS_TYPE_PTR, DNS_TYPE_NS, DNS_TYPE_CNAME))
switch (a->key->type) {
case DNS_TYPE_PTR:
case DNS_TYPE_NS:
case DNS_TYPE_CNAME:
return dns_name_equal(a->ptr.name, b->ptr.name);
else if (a->key->type == DNS_TYPE_HINFO)
return strcasecmp(a->hinfo.cpu, b->hinfo.cpu) == 0 &&
strcasecmp(a->hinfo.os, b->hinfo.os) == 0;
else if (a->key->type == DNS_TYPE_A)
case DNS_TYPE_HINFO:
return strcaseeq(a->hinfo.cpu, b->hinfo.cpu) &&
strcaseeq(a->hinfo.os, b->hinfo.os);
case DNS_TYPE_A:
return memcmp(&a->a.in_addr, &b->a.in_addr, sizeof(struct in_addr)) == 0;
else if (a->key->type == DNS_TYPE_AAAA)
case DNS_TYPE_AAAA:
return memcmp(&a->aaaa.in6_addr, &b->aaaa.in6_addr, sizeof(struct in6_addr)) == 0;
else if (a->key->type == DNS_TYPE_SOA) {
case DNS_TYPE_SOA:
r = dns_name_equal(a->soa.mname, b->soa.mname);
if (r <= 0)
return r;
@ -289,9 +322,95 @@ int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecor
a->soa.retry == b->soa.retry &&
a->soa.expire == b->soa.expire &&
a->soa.minimum == b->soa.minimum;
} else
default:
return a->generic.size == b->generic.size &&
memcmp(a->generic.data, b->generic.data, a->generic.size) == 0;
}
}
int dns_resource_record_to_string(const DnsResourceRecord *rr, char **ret) {
_cleanup_free_ char *k = NULL;
char *s;
int r;
assert(rr);
r = dns_resource_key_to_string(rr->key, &k);
if (r < 0)
return r;
switch (rr->key->type) {
case DNS_TYPE_PTR:
case DNS_TYPE_NS:
case DNS_TYPE_CNAME:
s = strjoin(k, " ", rr->ptr.name, NULL);
if (!s)
return -ENOMEM;
break;
case DNS_TYPE_HINFO:
s = strjoin(k, " ", rr->hinfo.cpu, " ", rr->hinfo.os, NULL);
if (!s)
return -ENOMEM;
break;
case DNS_TYPE_A: {
_cleanup_free_ char *x = NULL;
r = in_addr_to_string(AF_INET, (const union in_addr_union*) &rr->a.in_addr, &x);
if (r < 0)
return r;
s = strjoin(k, " ", x, NULL);
if (!s)
return -ENOMEM;
break;
}
case DNS_TYPE_AAAA: {
_cleanup_free_ char *x = NULL;
r = in_addr_to_string(AF_INET6, (const union in_addr_union*) &rr->aaaa.in6_addr, &x);
if (r < 0)
return r;
s = strjoin(k, " ", x, NULL);
if (!s)
return -ENOMEM;
break;
}
case DNS_TYPE_SOA:
r = asprintf(&s, "%s %s %s %u %u %u %u %u",
k,
strna(rr->soa.mname),
strna(rr->soa.rname),
rr->soa.serial,
rr->soa.refresh,
rr->soa.retry,
rr->soa.expire,
rr->soa.minimum);
if (r < 0)
return -ENOMEM;
break;
default: {
_cleanup_free_ char *x = NULL;
x = hexmem(rr->generic.data, rr->generic.size);
if (!x)
return -ENOMEM;
s = strjoin(k, " ", x, NULL);
if (!s)
return -ENOMEM;
break;
}}
*ret = s;
return 0;
}
const char *dns_class_to_string(uint16_t class) {
@ -308,64 +427,66 @@ const char *dns_class_to_string(uint16_t class) {
return NULL;
}
int dns_class_from_string(const char *s, uint16_t *class) {
assert(s);
assert(class);
if (strcaseeq(s, "IN"))
*class = DNS_CLASS_IN;
else if (strcaseeq(s, "ANY"))
*class = DNS_TYPE_ANY;
else
return -EINVAL;
return 0;
}
static const struct {
uint16_t type;
const char *name;
} dns_types[] = {
{ DNS_TYPE_A, "A" },
{ DNS_TYPE_NS, "NS" },
{ DNS_TYPE_CNAME, "CNAME" },
{ DNS_TYPE_SOA, "SOA" },
{ DNS_TYPE_PTR, "PTR" },
{ DNS_TYPE_HINFO, "HINFO" },
{ DNS_TYPE_MX, "MX" },
{ DNS_TYPE_TXT, "TXT" },
{ DNS_TYPE_AAAA, "AAAA" },
{ DNS_TYPE_SRV, "SRV" },
{ DNS_TYPE_SSHFP, "SSHFP" },
{ DNS_TYPE_DNAME, "DNAME" },
{ DNS_TYPE_ANY, "ANY" },
{ DNS_TYPE_OPT, "OPT" },
{ DNS_TYPE_TKEY, "TKEY" },
{ DNS_TYPE_TSIG, "TSIG" },
{ DNS_TYPE_IXFR, "IXFR" },
{ DNS_TYPE_AXFR, "AXFR" },
};
const char *dns_type_to_string(uint16_t type) {
unsigned i;
switch (type) {
case DNS_TYPE_A:
return "A";
case DNS_TYPE_NS:
return "NS";
case DNS_TYPE_CNAME:
return "CNAME";
case DNS_TYPE_SOA:
return "SOA";
case DNS_TYPE_PTR:
return "PTR";
case DNS_TYPE_HINFO:
return "HINFO";
case DNS_TYPE_MX:
return "MX";
case DNS_TYPE_TXT:
return "TXT";
case DNS_TYPE_AAAA:
return "AAAA";
case DNS_TYPE_SRV:
return "SRV";
case DNS_TYPE_SSHFP:
return "SSHFP";
case DNS_TYPE_DNAME:
return "DNAME";
case DNS_TYPE_ANY:
return "ANY";
case DNS_TYPE_OPT:
return "OPT";
case DNS_TYPE_TKEY:
return "TKEY";
case DNS_TYPE_TSIG:
return "TSIG";
case DNS_TYPE_IXFR:
return "IXFR";
case DNS_TYPE_AXFR:
return "AXFR";
}
for (i = 0; i < ELEMENTSOF(dns_types); i++)
if (dns_types[i].type == type)
return dns_types[i].name;
return NULL;
}
int dns_type_from_string(const char *s, uint16_t *type) {
unsigned i;
assert(s);
assert(type);
for (i = 0; i < ELEMENTSOF(dns_types); i++)
if (strcaseeq(dns_types[i].name, s)) {
*type = dns_types[i].type;
return 0;
}
return -EINVAL;
}

View File

@ -137,6 +137,7 @@ int dns_resource_key_match_rr(const DnsResourceKey *key, const DnsResourceRecord
int dns_resource_key_match_cname(const DnsResourceKey *key, const DnsResourceRecord *rr);
unsigned long dns_resource_key_hash_func(const void *i, const uint8_t hash_key[HASH_KEY_SIZE]);
int dns_resource_key_compare_func(const void *a, const void *b);
int dns_resource_key_to_string(const DnsResourceKey *key, char **ret);
DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceKey*, dns_resource_key_unref);
DnsResourceRecord* dns_resource_record_new(DnsResourceKey *key);
@ -145,7 +146,11 @@ DnsResourceRecord* dns_resource_record_ref(DnsResourceRecord *rr);
DnsResourceRecord* dns_resource_record_unref(DnsResourceRecord *rr);
int dns_resource_record_new_reverse(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name);
int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b);
int dns_resource_record_to_string(const DnsResourceRecord *rr, char **ret);
DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref);
const char *dns_type_to_string(uint16_t type);
int dns_type_from_string(const char *name, uint16_t *type);
const char *dns_class_to_string(uint16_t type);
int dns_class_from_string(const char *name, uint16_t *class);