diff options
author | Harald Welte <laforge@osmocom.org> | 2020-01-12 16:25:47 +0100 |
---|---|---|
committer | Harald Welte <laforge@osmocom.org> | 2020-01-12 16:27:42 +0100 |
commit | 110a49f69f29fed844d8743b76fd748f4a14812a (patch) | |
tree | fa46259f4cc310bcf79275729d9b3fb045b07eec /src | |
parent | 41fe3625915c456513544b99ba8c057c0f650b3c (diff) |
Revert "add mDNS lookup method to libosmo-mslookup"
This reverts commit f10463c5fc6d9e786ab7c648d99f7450f9a25906, as it
causes all OBS osmo-hlr builds to fail in the mslookup_client_mdns test.
Change-Id: I5aec5b59f304c7f732c4a31131beedf29c966d9d
Diffstat (limited to 'src')
-rw-r--r-- | src/mslookup/Makefile.am | 5 | ||||
-rw-r--r-- | src/mslookup/mdns.c | 425 | ||||
-rw-r--r-- | src/mslookup/mdns_msg.c | 261 | ||||
-rw-r--r-- | src/mslookup/mdns_rfc.c | 265 | ||||
-rw-r--r-- | src/mslookup/mdns_sock.c | 144 | ||||
-rw-r--r-- | src/mslookup/mslookup_client_mdns.c | 235 |
6 files changed, 0 insertions, 1335 deletions
diff --git a/src/mslookup/Makefile.am b/src/mslookup/Makefile.am index 07fb6f4..01be401 100644 --- a/src/mslookup/Makefile.am +++ b/src/mslookup/Makefile.am @@ -10,14 +10,9 @@ AM_LDFLAGS = $(COVERAGE_LDFLAGS) lib_LTLIBRARIES = libosmo-mslookup.la libosmo_mslookup_la_SOURCES = \ - mdns.c \ - mdns_msg.c \ - mdns_rfc.c \ - mdns_sock.c \ mslookup.c \ mslookup_client.c \ mslookup_client_fake.c \ - mslookup_client_mdns.c \ $(NULL) libosmo_mslookup_la_LDFLAGS = -version-info $(LIBVERSION) diff --git a/src/mslookup/mdns.c b/src/mslookup/mdns.c deleted file mode 100644 index 4742a7c..0000000 --- a/src/mslookup/mdns.c +++ /dev/null @@ -1,425 +0,0 @@ -/* mslookup specific functions for encoding and decoding mslookup queries/results into mDNS packets, using the high - * level functions from mdns_msg.c and mdns_record.c to build the request/answer messages. */ - -/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> - * - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <osmocom/hlr/logging.h> -#include <osmocom/core/msgb.h> -#include <osmocom/mslookup/mslookup.h> -#include <osmocom/mslookup/mdns_msg.h> -#include <osmocom/mslookup/mdns_rfc.h> -#include <errno.h> -#include <inttypes.h> - -static struct msgb *osmo_mdns_msgb_alloc(const char *label) -{ - return msgb_alloc(1024, label); -} - -/*! Combine the mslookup query service, ID and ID type into a domain string. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" - * \returns allocated buffer with the resulting domain (i.e. "sip.voice.123.msisdn.mdns.osmocom.org") on success, - * NULL on failure. - */ -static char *domain_from_query(void *ctx, const struct osmo_mslookup_query *query, const char *domain_suffix) -{ - const char *id; - - /* Get id from query */ - switch (query->id.type) { - case OSMO_MSLOOKUP_ID_IMSI: - id = query->id.imsi; - break; - case OSMO_MSLOOKUP_ID_MSISDN: - id = query->id.msisdn; - break; - default: - LOGP(DMSLOOKUP, LOGL_ERROR, "can't encode mslookup query id type %i", query->id.type); - return NULL; - } - - return talloc_asprintf(ctx, "%s.%s.%s.%s", query->service, id, osmo_mslookup_id_type_name(query->id.type), - domain_suffix); -} - -/*! Split up query service, ID and ID type from a domain string into a mslookup query. - * \param[in] domain with domain_suffix, e.g. "sip.voice.123.msisdn.mdns.osmocom.org" - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. It is not part of the resulting struct osmo_mslookup_query, so we - * remove it in this function. Example: "mdns.osmocom.org" - */ -int query_from_domain(struct osmo_mslookup_query *query, const char *domain, const char *domain_suffix) -{ - int domain_len = strlen(domain) - strlen(domain_suffix) - 1; - char domain_buf[OSMO_MDNS_RFC_MAX_NAME_LEN]; - - if (domain_len <= 0 || domain_len >= sizeof(domain_buf)) - return -EINVAL; - - if (domain[domain_len] != '.' || strcmp(domain + domain_len + 1, domain_suffix) != 0) - return -EINVAL; - - memcpy(domain_buf, domain, domain_len); - domain_buf[domain_len] = '\0'; - return osmo_mslookup_query_init_from_domain_str(query, domain_buf); -} - -/*! Encode a mslookup query into a mDNS packet. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" - * \returns msgb, or NULL on error. - */ -struct msgb *osmo_mdns_query_encode(void *ctx, uint16_t packet_id, const struct osmo_mslookup_query *query, - const char *domain_suffix) -{ - struct osmo_mdns_msg_request req = {0}; - struct msgb *msg = osmo_mdns_msgb_alloc(__func__); - - req.id = packet_id; - req.type = OSMO_MDNS_RFC_RECORD_TYPE_ALL; - req.domain = domain_from_query(ctx, query, domain_suffix); - if (!req.domain) - goto error; - if (osmo_mdns_msg_request_encode(ctx, msg, &req)) - goto error; - talloc_free(req.domain); - return msg; -error: - msgb_free(msg); - talloc_free(req.domain); - return NULL; -} - -/*! Decode a mDNS request packet into a mslookup query. - * \param[out] packet_id the result must be sent with the same packet_id. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" - * \returns allocated mslookup query on success, NULL on error. - */ -struct osmo_mslookup_query *osmo_mdns_query_decode(void *ctx, const uint8_t *data, size_t data_len, - uint16_t *packet_id, const char *domain_suffix) -{ - struct osmo_mdns_msg_request *req = NULL; - struct osmo_mslookup_query *query = NULL; - - req = osmo_mdns_msg_request_decode(ctx, data, data_len); - if (!req) - return NULL; - - query = talloc_zero(ctx, struct osmo_mslookup_query); - OSMO_ASSERT(query); - if (query_from_domain(query, req->domain, domain_suffix) < 0) - goto error_free; - - *packet_id = req->id; - talloc_free(req); - return query; -error_free: - talloc_free(req); - talloc_free(query); - return NULL; -} - -/*! Parse sockaddr_str from mDNS record, so the mslookup result can be filled with it. - * \param[out] sockaddr_str resulting IPv4 or IPv6 sockaddr_str. - * \param[in] rec single record of the abstracted list of mDNS records - * \returns 0 on success, -EINVAL on error. - */ -static int sockaddr_str_from_mdns_record(struct osmo_sockaddr_str *sockaddr_str, struct osmo_mdns_record *rec) -{ - switch (rec->type) { - case OSMO_MDNS_RFC_RECORD_TYPE_A: - if (rec->length != 4) { - LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected length of A record\n"); - return -EINVAL; - } - osmo_sockaddr_str_from_32(sockaddr_str, *(uint32_t *)rec->data, 0); - break; - case OSMO_MDNS_RFC_RECORD_TYPE_AAAA: - if (rec->length != 16) { - LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected length of AAAA record\n"); - return -EINVAL; - } - osmo_sockaddr_str_from_in6_addr(sockaddr_str, (struct in6_addr*)rec->data, 0); - break; - default: - LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected record type\n"); - return -EINVAL; - } - return 0; -} - -/*! Encode a successful mslookup result, along with the original query and packet_id into one mDNS answer packet. - * - * The records in the packet are ordered as follows: - * 1) "age", ip_v4/v6, "port" (only IPv4 or IPv6 present) or - * 2) "age", ip_v4, "port", ip_v6, "port" (both IPv4 and v6 present). - * "age" and "port" are TXT records, ip_v4 is an A record, ip_v6 is an AAAA record. - * - * \param[in] packet_id as received in osmo_mdns_query_decode(). - * \param[in] query the original query, so we can send the domain back in the answer (i.e. "sip.voice.1234.msisdn"). - * \param[in] result holds the age, IPs and ports of the queried service. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" - * \returns msg on success, NULL on error. - */ -struct msgb *osmo_mdns_result_encode(void *ctx, uint16_t packet_id, const struct osmo_mslookup_query *query, - const struct osmo_mslookup_result *result, const char *domain_suffix) -{ - struct osmo_mdns_msg_answer ans = {}; - struct osmo_mdns_record *rec_age = NULL; - struct osmo_mdns_record rec_ip_v4 = {0}; - struct osmo_mdns_record rec_ip_v6 = {0}; - struct osmo_mdns_record *rec_ip_v4_port = NULL; - struct osmo_mdns_record *rec_ip_v6_port = NULL; - struct in_addr rec_ip_v4_in; - struct in6_addr rec_ip_v6_in; - struct msgb *msg = osmo_mdns_msgb_alloc(__func__); - char buf[256]; - - ctx = talloc_named(ctx, 0, "osmo_mdns_result_encode"); - - /* Prepare answer (ans) */ - ans.domain = domain_from_query(ctx, query, domain_suffix); - if (!ans.domain) - goto error; - ans.id = packet_id; - INIT_LLIST_HEAD(&ans.records); - - /* Record for age */ - rec_age = osmo_mdns_record_txt_keyval_encode(ctx, "age", "%"PRIu32, result->age); - OSMO_ASSERT(rec_age); - llist_add_tail(&rec_age->list, &ans.records); - - /* Records for IPv4 */ - if (osmo_sockaddr_str_is_set(&result->host_v4)) { - if (osmo_sockaddr_str_to_in_addr(&result->host_v4, &rec_ip_v4_in) < 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode ipv4: %s\n", - osmo_mslookup_result_name_b(buf, sizeof(buf), query, result)); - goto error; - } - rec_ip_v4.type = OSMO_MDNS_RFC_RECORD_TYPE_A; - rec_ip_v4.data = (uint8_t *)&rec_ip_v4_in; - rec_ip_v4.length = sizeof(rec_ip_v4_in); - llist_add_tail(&rec_ip_v4.list, &ans.records); - - rec_ip_v4_port = osmo_mdns_record_txt_keyval_encode(ctx, "port", "%"PRIu16, result->host_v4.port); - OSMO_ASSERT(rec_ip_v4_port); - llist_add_tail(&rec_ip_v4_port->list, &ans.records); - } - - /* Records for IPv6 */ - if (osmo_sockaddr_str_is_set(&result->host_v6)) { - if (osmo_sockaddr_str_to_in6_addr(&result->host_v6, &rec_ip_v6_in) < 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode ipv6: %s\n", - osmo_mslookup_result_name_b(buf, sizeof(buf), query, result)); - goto error; - } - rec_ip_v6.type = OSMO_MDNS_RFC_RECORD_TYPE_AAAA; - rec_ip_v6.data = (uint8_t *)&rec_ip_v6_in; - rec_ip_v6.length = sizeof(rec_ip_v6_in); - llist_add_tail(&rec_ip_v6.list, &ans.records); - - rec_ip_v6_port = osmo_mdns_record_txt_keyval_encode(ctx, "port", "%"PRIu16, result->host_v6.port); - OSMO_ASSERT(rec_ip_v6_port); - llist_add_tail(&rec_ip_v6_port->list, &ans.records); - } - - if (osmo_mdns_msg_answer_encode(ctx, msg, &ans)) { - LOGP(DMSLOOKUP, LOGL_ERROR, "failed to encode mDNS answer: %s\n", - osmo_mslookup_result_name_b(buf, sizeof(buf), query, result)); - goto error; - } - talloc_free(ctx); - return msg; -error: - msgb_free(msg); - talloc_free(ctx); - return NULL; -} - -static int decode_uint32_t(const char *str, uint32_t *val) -{ - long long int lld; - char *endptr = NULL; - *val = 0; - errno = 0; - lld = strtoll(str, &endptr, 10); - if (errno || !endptr || *endptr) - return -EINVAL; - if (lld < 0 || lld > UINT32_MAX) - return -EINVAL; - *val = lld; - return 0; -} - -static int decode_port(const char *str, uint16_t *port) -{ - uint32_t val; - if (decode_uint32_t(str, &val)) - return -EINVAL; - if (val > 65535) - return -EINVAL; - *port = val; - return 0; -} - -/*! Read expected mDNS records into mslookup result. - * - * The records in the packet must be ordered as follows: - * 1) "age", ip_v4/v6, "port" (only IPv4 or IPv6 present) or - * 2) "age", ip_v4, "port", ip_v6, "port" (both IPv4 and v6 present). - * "age" and "port" are TXT records, ip_v4 is an A record, ip_v6 is an AAAA record. - * - * \param[out] result holds the age, IPs and ports of the queried service. - * \param[in] ans abstracted mDNS answer with a list of resource records. - * \returns 0 on success, -EINVAL on error. - */ -int osmo_mdns_result_from_answer(struct osmo_mslookup_result *result, const struct osmo_mdns_msg_answer *ans) -{ - struct osmo_mdns_record *rec; - char txt_key[64]; - char txt_value[64]; - bool found_age = false; - bool found_ip_v4 = false; - bool found_ip_v6 = false; - struct osmo_sockaddr_str *expect_port_for = NULL; - - *result = (struct osmo_mslookup_result){}; - - result->rc = OSMO_MSLOOKUP_RC_NONE; - - llist_for_each_entry(rec, &ans->records, list) { - switch (rec->type) { - case OSMO_MDNS_RFC_RECORD_TYPE_A: - if (expect_port_for) { - LOGP(DMSLOOKUP, LOGL_ERROR, - "'A' record found, but still expecting a 'port' value first\n"); - return -EINVAL; - } - if (found_ip_v4) { - LOGP(DMSLOOKUP, LOGL_ERROR, "'A' record found twice in mDNS answer\n"); - return -EINVAL; - } - found_ip_v4 = true; - expect_port_for = &result->host_v4; - if (sockaddr_str_from_mdns_record(expect_port_for, rec)) { - LOGP(DMSLOOKUP, LOGL_ERROR, "'A' record with invalid address data\n"); - return -EINVAL; - } - break; - case OSMO_MDNS_RFC_RECORD_TYPE_AAAA: - if (expect_port_for) { - LOGP(DMSLOOKUP, LOGL_ERROR, - "'AAAA' record found, but still expecting a 'port' value first\n"); - return -EINVAL; - } - if (found_ip_v6) { - LOGP(DMSLOOKUP, LOGL_ERROR, "'AAAA' record found twice in mDNS answer\n"); - return -EINVAL; - } - found_ip_v6 = true; - expect_port_for = &result->host_v6; - if (sockaddr_str_from_mdns_record(expect_port_for, rec) != 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "'AAAA' record with invalid address data\n"); - return -EINVAL; - } - break; - case OSMO_MDNS_RFC_RECORD_TYPE_TXT: - if (osmo_mdns_record_txt_keyval_decode(rec, txt_key, sizeof(txt_key), - txt_value, sizeof(txt_value)) != 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "failed to decode txt record\n"); - return -EINVAL; - } - if (strcmp(txt_key, "age") == 0) { - if (found_age) { - LOGP(DMSLOOKUP, LOGL_ERROR, "duplicate 'TXT' record for 'age'\n"); - return -EINVAL; - } - found_age = true; - if (decode_uint32_t(txt_value, &result->age)) { - LOGP(DMSLOOKUP, LOGL_ERROR, - "'TXT' record: invalid 'age' value ('age=%s')\n", txt_value); - return -EINVAL; - } - } else if (strcmp(txt_key, "port") == 0) { - if (!expect_port_for) { - LOGP(DMSLOOKUP, LOGL_ERROR, - "'TXT' record for 'port' without previous 'A' or 'AAAA' record\n"); - return -EINVAL; - } - if (decode_port(txt_value, &expect_port_for->port)) { - LOGP(DMSLOOKUP, LOGL_ERROR, - "'TXT' record: invalid 'port' value ('port=%s')\n", txt_value); - return -EINVAL; - } - expect_port_for = NULL; - } else { - LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected key '%s' in TXT record\n", txt_key); - return -EINVAL; - } - break; - default: - LOGP(DMSLOOKUP, LOGL_ERROR, "unexpected record type\n"); - return -EINVAL; - } - } - - /* Check if everything was found */ - if (!found_age || !(found_ip_v4 || found_ip_v6) || expect_port_for) { - LOGP(DMSLOOKUP, LOGL_ERROR, "missing resource records in mDNS answer\n"); - return -EINVAL; - } - - result->rc = OSMO_MSLOOKUP_RC_RESULT; - return 0; -} - -/*! Decode a mDNS answer packet into a mslookup result, query and packet_id. - * \param[out] packet_id same ID as sent in the request packet. - * \param[out] query the original query (service, ID, ID type). - * \param[out] result holds the age, IPs and ports of the queried service. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" - * \returns 0 on success, -EINVAL on error. - */ -int osmo_mdns_result_decode(void *ctx, const uint8_t *data, size_t data_len, uint16_t *packet_id, - struct osmo_mslookup_query *query, struct osmo_mslookup_result *result, - const char *domain_suffix) -{ - int rc = -EINVAL; - struct osmo_mdns_msg_answer *ans; - ans = osmo_mdns_msg_answer_decode(ctx, data, data_len); - if (!ans) - goto exit_free; - - if (query_from_domain(query, ans->domain, domain_suffix) < 0) - goto exit_free; - - if (osmo_mdns_result_from_answer(result, ans) < 0) - goto exit_free; - - *packet_id = ans->id; - rc = 0; - -exit_free: - talloc_free(ans); - return rc; -} diff --git a/src/mslookup/mdns_msg.c b/src/mslookup/mdns_msg.c deleted file mode 100644 index da65fef..0000000 --- a/src/mslookup/mdns_msg.c +++ /dev/null @@ -1,261 +0,0 @@ -/* High level mDNS encoding and decoding functions for whole messages: - * Request message (header, question) - * Answer message (header, resource record 1, ... resource record N)*/ - -/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> - * - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <errno.h> -#include <string.h> -#include <osmocom/hlr/logging.h> -#include <osmocom/mslookup/mdns_msg.h> - -/*! Encode request message into one mDNS packet, consisting of the header section and one question section. - * \returns 0 on success, -EINVAL on error. - */ -int osmo_mdns_msg_request_encode(void *ctx, struct msgb *msg, const struct osmo_mdns_msg_request *req) -{ - struct osmo_mdns_rfc_header hdr = {0}; - struct osmo_mdns_rfc_question qst = {0}; - - hdr.id = req->id; - hdr.qdcount = 1; - osmo_mdns_rfc_header_encode(msg, &hdr); - - qst.domain = req->domain; - qst.qtype = req->type; - qst.qclass = OSMO_MDNS_RFC_CLASS_IN; - if (osmo_mdns_rfc_question_encode(ctx, msg, &qst) != 0) - return -EINVAL; - - return 0; -} - -/*! Decode request message from a mDNS packet, consisting of the header section and one question section. - * \returns allocated request message on success, NULL on error. - */ -struct osmo_mdns_msg_request *osmo_mdns_msg_request_decode(void *ctx, const uint8_t *data, size_t data_len) -{ - struct osmo_mdns_rfc_header hdr = {0}; - size_t hdr_len = sizeof(struct osmo_mdns_rfc_header); - struct osmo_mdns_rfc_question* qst = NULL; - struct osmo_mdns_msg_request *ret = NULL; - - if (data_len < hdr_len || osmo_mdns_rfc_header_decode(data, hdr_len, &hdr) != 0 || hdr.qr != 0) - return NULL; - - qst = osmo_mdns_rfc_question_decode(ctx, data + hdr_len, data_len - hdr_len); - if (!qst) - return NULL; - - ret = talloc_zero(ctx, struct osmo_mdns_msg_request); - ret->id = hdr.id; - ret->domain = talloc_strdup(ret, qst->domain); - ret->type = qst->qtype; - - talloc_free(qst); - return ret; -} - -/*! Initialize the linked list for resource records in a answer message. */ -void osmo_mdns_msg_answer_init(struct osmo_mdns_msg_answer *ans) -{ - *ans = (struct osmo_mdns_msg_answer){}; - INIT_LLIST_HEAD(&ans->records); -} - -/*! Encode answer message into one mDNS packet, consisting of the header section and N resource records. - * - * To keep things simple, this sends the domain with each resource record. Other DNS implementations make use of - * "message compression", which would send a question section with the domain before the resource records, and then - * point inside each resource record with an offset back to the domain in the question section (RFC 1035 4.1.4). - * \returns 0 on success, -EINVAL on error. - */ -int osmo_mdns_msg_answer_encode(void *ctx, struct msgb *msg, const struct osmo_mdns_msg_answer *ans) -{ - struct osmo_mdns_rfc_header hdr = {0}; - struct osmo_mdns_record *ans_record; - - hdr.id = ans->id; - hdr.qr = 1; - hdr.ancount = llist_count(&ans->records); - osmo_mdns_rfc_header_encode(msg, &hdr); - - llist_for_each_entry(ans_record, &ans->records, list) { - struct osmo_mdns_rfc_record rec = {0}; - - rec.domain = ans->domain; - rec.type = ans_record->type; - rec.class = OSMO_MDNS_RFC_CLASS_IN; - rec.ttl = 0; - rec.rdlength = ans_record->length; - rec.rdata = ans_record->data; - - if (osmo_mdns_rfc_record_encode(ctx, msg, &rec) != 0) - return -EINVAL; - } - - return 0; -} - -/*! Decode answer message from a mDNS packet. - * - * Answer messages must consist of one header and one or more resource records. An additional question section or - * message compression (RFC 1035 4.1.4) are not supported. -* \returns allocated answer message on success, NULL on error. - */ -struct osmo_mdns_msg_answer *osmo_mdns_msg_answer_decode(void *ctx, const uint8_t *data, size_t data_len) -{ - struct osmo_mdns_rfc_header hdr = {}; - size_t hdr_len = sizeof(struct osmo_mdns_rfc_header); - struct osmo_mdns_msg_answer *ret = talloc_zero(ctx, struct osmo_mdns_msg_answer); - - /* Parse header section */ - if (data_len < hdr_len || osmo_mdns_rfc_header_decode(data, hdr_len, &hdr) != 0 || hdr.qr != 1) - goto error; - ret->id = hdr.id; - data_len -= hdr_len; - data += hdr_len; - - /* Parse resource records */ - INIT_LLIST_HEAD(&ret->records); - while (data_len) { - size_t record_len; - struct osmo_mdns_rfc_record *rec; - struct osmo_mdns_record* ret_record; - - rec = osmo_mdns_rfc_record_decode(ret, data, data_len, &record_len); - if (!rec) - goto error; - - /* Copy domain to ret */ - if (ret->domain) { - if (strcmp(ret->domain, rec->domain) != 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "domain mismatch in resource records ('%s' vs '%s')\n", - ret->domain, rec->domain); - goto error; - } - } - else - ret->domain = talloc_strdup(ret, rec->domain); - - /* Add simplified record to ret */ - ret_record = talloc_zero(ret, struct osmo_mdns_record); - ret_record->type = rec->type; - ret_record->length = rec->rdlength; - ret_record->data = talloc_memdup(ret_record, rec->rdata, rec->rdlength); - llist_add_tail(&ret_record->list, &ret->records); - - data += record_len; - data_len -= record_len; - talloc_free(rec); - } - - /* Verify record count */ - if (llist_count(&ret->records) != hdr.ancount) { - LOGP(DMSLOOKUP, LOGL_ERROR, "amount of parsed records (%i) doesn't match count in header (%i)\n", - llist_count(&ret->records), hdr.ancount); - goto error; - } - - return ret; -error: - talloc_free(ret); - return NULL; -} - -/*! Get a TXT resource record, which stores a key=value string. - * \returns allocated resource record on success, NULL on error. - */ -static struct osmo_mdns_record *_osmo_mdns_record_txt_encode(void *ctx, const char *key, const char *value) -{ - struct osmo_mdns_record *ret = talloc_zero(ctx, struct osmo_mdns_record); - size_t len = strlen(key) + 1 + strlen(value); - - if (len > OSMO_MDNS_RFC_MAX_CHARACTER_STRING_LEN - 1) - return NULL; - - /* redundant len is required, see RFC 1035 3.3.14 and 3.3. */ - ret->data = (uint8_t *)talloc_asprintf(ctx, "%c%s=%s", (char)len, key, value); - if (!ret->data) - return NULL; - ret->type = OSMO_MDNS_RFC_RECORD_TYPE_TXT; - ret->length = len + 1; - return ret; -} - -/*! Get a TXT resource record, which stores a key=value string, but build value from a format string. - * \returns allocated resource record on success, NULL on error. - */ -struct osmo_mdns_record *osmo_mdns_record_txt_keyval_encode(void *ctx, const char *key, const char *value_fmt, ...) -{ - va_list ap; - char *value = NULL; - struct osmo_mdns_record *r; - - if (!value_fmt) - return _osmo_mdns_record_txt_encode(ctx, key, ""); - - va_start(ap, value_fmt); - value = talloc_vasprintf(ctx, value_fmt, ap); - if (!value) - return NULL; - va_end(ap); - r = _osmo_mdns_record_txt_encode(ctx, key, value); - talloc_free(value); - return r; -} - -/*! Decode a TXT resource record, which stores a key=value string. - * \returns 0 on success, -EINVAL on error. - */ -int osmo_mdns_record_txt_keyval_decode(const struct osmo_mdns_record *rec, - char *key_buf, size_t key_size, char *value_buf, size_t value_size) -{ - const char *key_value; - const char *key_value_end; - const char *sep; - const char *value; - - if (rec->type != OSMO_MDNS_RFC_RECORD_TYPE_TXT) - return -EINVAL; - - key_value = (const char *)rec->data; - key_value_end = key_value + rec->length; - - /* Verify and then skip the redundant string length byte */ - if (*key_value != rec->length - 1) - return -EINVAL; - key_value++; - - if (key_value >= key_value_end) - return -EINVAL; - - /* Find equals sign */ - sep = osmo_strnchr(key_value, key_value_end - key_value, '='); - if (!sep) - return -EINVAL; - - /* Parse key */ - osmo_print_n(key_buf, key_size, key_value, sep - key_value); - - /* Parse value */ - value = sep + 1; - osmo_print_n(value_buf, value_size, value, key_value_end - value); - return 0; -} diff --git a/src/mslookup/mdns_rfc.c b/src/mslookup/mdns_rfc.c deleted file mode 100644 index e1fc184..0000000 --- a/src/mslookup/mdns_rfc.c +++ /dev/null @@ -1,265 +0,0 @@ -/* Low level mDNS encoding and decoding functions of the qname IE, header/question sections and resource records, - * as described in these RFCs: - * - RFC 1035 (Domain names - implementation and specification) - * - RFC 3596 (DNS Extensions to Support IP Version 6) */ - -/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> - * - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <string.h> -#include <ctype.h> -#include <errno.h> -#include <osmocom/core/msgb.h> -#include <osmocom/core/bitvec.h> -#include <osmocom/core/logging.h> -#include <osmocom/mslookup/mdns_rfc.h> - -/* - * Encode/decode IEs - */ - -/*! Encode a domain string as qname (RFC 1035 4.1.2). - * \param[in] domain multiple labels separated by dots, e.g. "sip.voice.1234.msisdn". - * \returns allocated buffer with length-value pairs for each label (e.g. 0x03 "sip" 0x05 "voice" ...), NULL on error. - */ -char *osmo_mdns_rfc_qname_encode(void *ctx, const char *domain) -{ - char *domain_dup; - char *domain_iter; - char buf[OSMO_MDNS_RFC_MAX_NAME_LEN + 2] = ""; /* len(qname) is len(domain) +1 */ - struct osmo_strbuf sb = { .buf = buf, .len = sizeof(buf) }; - char *label; - - if (strlen(domain) > OSMO_MDNS_RFC_MAX_NAME_LEN) - return NULL; - - domain_iter = domain_dup = talloc_strdup(ctx, domain); - while ((label = strsep(&domain_iter, "."))) { - size_t len = strlen(label); - - /* Empty domain, dot at start, two dots in a row, or ending with a dot */ - if (!len) - goto error; - - OSMO_STRBUF_PRINTF(sb, "%c%s", (char)len, label); - } - - talloc_free(domain_dup); - return talloc_strdup(ctx, buf); - -error: - talloc_free(domain_dup); - return NULL; -} - -/*! Decode a domain string from a qname (RFC 1035 4.1.2). - * \param[in] qname buffer with length-value pairs for each label (e.g. 0x03 "sip" 0x05 "voice" ...) - * \param[in] qname_max_len amount of bytes that can be read at most from the memory location that qname points to. - * \returns allocated buffer with domain string, multiple labels separated by dots (e.g. "sip.voice.1234.msisdn"), - * NULL on error. - */ -char *osmo_mdns_rfc_qname_decode(void *ctx, const char *qname, size_t qname_max_len) -{ - const char *next_label, *qname_end = qname + qname_max_len; - char buf[OSMO_MDNS_RFC_MAX_NAME_LEN + 1]; - int i = 0; - - if (qname_max_len < 1) - return NULL; - - while (*qname) { - size_t len = *qname; - next_label = qname + len + 1; - - if (next_label >= qname_end || i + len > OSMO_MDNS_RFC_MAX_NAME_LEN) - return NULL; - - if (i) { - /* Two dots in a row is not allowed */ - if (buf[i - 1] == '.') - return NULL; - - buf[i] = '.'; - i++; - } - - memcpy(buf + i, qname + 1, len); - i += len; - qname = next_label; - } - buf[i] = '\0'; - - return talloc_strdup(ctx, buf); -} - -/* - * Encode/decode message sections - */ - -/*! Encode header section (RFC 1035 4.1.1). - * \param[in] msgb mesage buffer to which the encoded data will be appended. - */ -void osmo_mdns_rfc_header_encode(struct msgb *msg, const struct osmo_mdns_rfc_header *hdr) -{ - struct osmo_mdns_rfc_header *buf = (struct osmo_mdns_rfc_header *) msgb_put(msg, sizeof(*hdr)); - memcpy(buf, hdr, sizeof(*hdr)); - - osmo_store16be(buf->id, &buf->id); - osmo_store16be(buf->qdcount, &buf->qdcount); - osmo_store16be(buf->ancount, &buf->ancount); - osmo_store16be(buf->nscount, &buf->nscount); - osmo_store16be(buf->arcount, &buf->arcount); -} - -/*! Decode header section (RFC 1035 4.1.1). */ -int osmo_mdns_rfc_header_decode(const uint8_t *data, size_t data_len, struct osmo_mdns_rfc_header *hdr) -{ - if (data_len != sizeof(*hdr)) - return -EINVAL; - - memcpy(hdr, data, data_len); - - hdr->id = osmo_load16be(&hdr->id); - hdr->qdcount = osmo_load16be(&hdr->qdcount); - hdr->ancount = osmo_load16be(&hdr->ancount); - hdr->nscount = osmo_load16be(&hdr->nscount); - hdr->arcount = osmo_load16be(&hdr->arcount); - - return 0; -} - -/*! Encode question section (RFC 1035 4.1.2). - * \param[in] msgb mesage buffer to which the encoded data will be appended. - */ -int osmo_mdns_rfc_question_encode(void *ctx, struct msgb *msg, const struct osmo_mdns_rfc_question *qst) -{ - char *qname; - size_t qname_len; - uint8_t *qname_buf; - - /* qname */ - qname = osmo_mdns_rfc_qname_encode(ctx, qst->domain); - if (!qname) - return -EINVAL; - qname_len = strlen(qname) + 1; - qname_buf = msgb_put(msg, qname_len); - memcpy(qname_buf, qname, qname_len); - talloc_free(qname); - - /* qtype and qclass */ - msgb_put_u16(msg, qst->qtype); - msgb_put_u16(msg, qst->qclass); - - return 0; -} - -/*! Decode question section (RFC 1035 4.1.2). */ -struct osmo_mdns_rfc_question *osmo_mdns_rfc_question_decode(void *ctx, const uint8_t *data, size_t data_len) -{ - struct osmo_mdns_rfc_question *ret; - size_t qname_len = data_len - 4; - - if (data_len < 6) - return NULL; - - /* qname */ - ret = talloc_zero(ctx, struct osmo_mdns_rfc_question); - if (!ret) - return NULL; - ret->domain = osmo_mdns_rfc_qname_decode(ret, (const char *)data, qname_len); - if (!ret->domain) { - talloc_free(ret); - return NULL; - } - - /* qtype and qclass */ - ret->qtype = osmo_load16be(data + qname_len); - ret->qclass = osmo_load16be(data + qname_len + 2); - - return ret; -} - -/* - * Encode/decode resource records - */ - -/*! Encode one resource record (RFC 1035 4.1.3). - * \param[in] msgb mesage buffer to which the encoded data will be appended. - */ -int osmo_mdns_rfc_record_encode(void *ctx, struct msgb *msg, const struct osmo_mdns_rfc_record *rec) -{ - char *name; - size_t name_len; - uint8_t *buf; - - /* name */ - name = osmo_mdns_rfc_qname_encode(ctx, rec->domain); - if (!name) - return -EINVAL; - name_len = strlen(name) + 1; - buf = msgb_put(msg, name_len); - memcpy(buf, name, name_len); - talloc_free(name); - - /* type, class, ttl, rdlength */ - msgb_put_u16(msg, rec->type); - msgb_put_u16(msg, rec->class); - msgb_put_u32(msg, rec->ttl); - msgb_put_u16(msg, rec->rdlength); - - /* rdata */ - buf = msgb_put(msg, rec->rdlength); - memcpy(buf, rec->rdata, rec->rdlength); - return 0; -} - -/*! Decode one resource record (RFC 1035 4.1.3). */ -struct osmo_mdns_rfc_record *osmo_mdns_rfc_record_decode(void *ctx, const uint8_t *data, size_t data_len, - size_t *record_len) -{ - struct osmo_mdns_rfc_record *ret = talloc_zero(ctx, struct osmo_mdns_rfc_record); - size_t name_len; - - /* name */ - ret->domain = osmo_mdns_rfc_qname_decode(ret, (const char *)data, data_len - 10); - if (!ret->domain) - goto error; - name_len = strlen(ret->domain) + 2; - if (name_len + 10 > data_len) - goto error; - - /* type, class, ttl, rdlength */ - ret->type = osmo_load16be(data + name_len); - ret->class = osmo_load16be(data + name_len + 2); - ret->ttl = osmo_load32be(data + name_len + 4); - ret->rdlength = osmo_load16be(data + name_len + 8); - if (name_len + 10 + ret->rdlength > data_len) - goto error; - - /* rdata */ - ret->rdata = talloc_memdup(ret, data + name_len + 10, ret->rdlength); - if (!ret->rdata) - return NULL; - - *record_len = name_len + 10 + ret->rdlength; - return ret; -error: - talloc_free(ret); - return NULL; -} - diff --git a/src/mslookup/mdns_sock.c b/src/mslookup/mdns_sock.c deleted file mode 100644 index 5291660..0000000 --- a/src/mslookup/mdns_sock.c +++ /dev/null @@ -1,144 +0,0 @@ -/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> - * - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <errno.h> -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -#include <string.h> -#include <sys/types.h> -#include <sys/socket.h> -#include <arpa/inet.h> -#include <netinet/in.h> -#include <netdb.h> -#include <stdbool.h> -#include <talloc.h> -#include <osmocom/core/utils.h> -#include <osmocom/core/select.h> -#include <osmocom/hlr/logging.h> -#include <osmocom/mslookup/mdns_sock.h> - -/*! Open socket to send and receive multicast data. - * - * The socket is opened with SO_REUSEADDR, so we can bind to the same IP and port multiple times. This socket receives - * everything sent to that multicast IP/port, including its own data data sent from osmo_mdns_sock_send(). So whenever - * sending something, the receive callback will be called with the same data and should discard it. - * - * \param[in] ip multicast IPv4 or IPv6 address. - * \param[in] port port number. - * \param[in] cb callback for incoming data that will be passed to osmo_fd_setup (should read from osmo_fd->fd). - * \param[in] data userdata passed to osmo_fd (available in cb as osmo_fd->data). - * \param[in] priv_nr additional userdata integer passed to osmo_fd (available in cb as osmo_fd->priv_nr). - * \returns allocated osmo_mdns_sock, NULL on error. - */ -struct osmo_mdns_sock *osmo_mdns_sock_init(void *ctx, const char *ip, unsigned int port, - int (*cb)(struct osmo_fd *fd, unsigned int what), - void *data, unsigned int priv_nr) -{ - struct osmo_mdns_sock *ret; - int sock, rc; - struct addrinfo hints = {0}; - struct ip_mreq multicast_req = {0}; - in_addr_t iface = INADDR_ANY; - char portbuf[10]; - int y = 1; - - snprintf(portbuf, sizeof(portbuf) -1, "%u", port); - ret = talloc_zero(ctx, struct osmo_mdns_sock); - OSMO_ASSERT(ret); - - /* Fill addrinfo */ - hints.ai_family = PF_UNSPEC; - hints.ai_socktype = SOCK_DGRAM; - hints.ai_flags = (AI_PASSIVE | AI_NUMERICHOST); - rc = getaddrinfo(ip, portbuf, &hints, &ret->ai); - if (rc != 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: getaddrinfo: %s\n", gai_strerror(rc)); - ret->ai = NULL; - goto error; - } - - /* Open socket */ - sock = socket(ret->ai->ai_family, ret->ai->ai_socktype, 0); - if (sock == -1) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: socket: %s\n", strerror(errno)); - goto error; - } - - /* Set multicast options */ - rc = setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF, (char*)&iface, sizeof(iface)); - if (rc == -1) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: setsockopt: %s\n", strerror(errno)); - goto error; - } - memcpy(&multicast_req.imr_multiaddr, &((struct sockaddr_in*)(ret->ai->ai_addr))->sin_addr, - sizeof(multicast_req.imr_multiaddr)); - multicast_req.imr_interface.s_addr = htonl(INADDR_ANY); - rc = setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char*)&multicast_req, sizeof(multicast_req)); - if (rc == -1) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: setsockopt: %s\n", strerror(errno)); - goto error; - } - - /* Always allow binding the same IP and port twice. This is needed in OsmoHLR (where the code becomes cleaner by - * just using a different socket for server and client code) and in the mslookup_client_mdns_test. Also for - * osmo-mslookup-client if it is running multiple times in parallel (i.e. two incoming calls almost at the same - * time need to be resolved with the simple dialplan example that just starts new processes). */ - rc = setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&y, sizeof(y)); - if (rc == -1) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: setsockopt: %s\n", strerror(errno)); - goto error; - } - - /* Bind and register osmo_fd callback */ - rc = bind(sock, ret->ai->ai_addr, ret->ai->ai_addrlen); - if (rc == -1) { - LOGP(DMSLOOKUP, LOGL_ERROR, "osmo_mdns_sock_init: bind: %s\n", strerror(errno)); - goto error; - } - osmo_fd_setup(&ret->osmo_fd, sock, OSMO_FD_READ, cb, data, priv_nr); - if (osmo_fd_register(&ret->osmo_fd) != 0) - goto error; - - return ret; -error: - if (ret->ai) - freeaddrinfo(ret->ai); - talloc_free(ret); - return NULL; -} - -/*! Send msgb over mdns_sock and consume msgb. - * \returns 0 on success, -1 on error. - */ -int osmo_mdns_sock_send(const struct osmo_mdns_sock *mdns_sock, struct msgb *msg) -{ - size_t len = msgb_length(msg); - int rc = sendto(mdns_sock->osmo_fd.fd, msgb_data(msg), len, 0, mdns_sock->ai->ai_addr, - mdns_sock->ai->ai_addrlen); - msgb_free(msg); - return (rc == len) ? 0 : -1; -} - -/*! Tear down osmo_mdns_sock. */ -void osmo_mdns_sock_cleanup(struct osmo_mdns_sock *mdns_sock) -{ - osmo_fd_close(&mdns_sock->osmo_fd); - freeaddrinfo(mdns_sock->ai); - talloc_free(mdns_sock); -} diff --git a/src/mslookup/mslookup_client_mdns.c b/src/mslookup/mslookup_client_mdns.c deleted file mode 100644 index 7ba3502..0000000 --- a/src/mslookup/mslookup_client_mdns.c +++ /dev/null @@ -1,235 +0,0 @@ -/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de> - * - * All Rights Reserved - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License along - * with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <string.h> -#include <sys/types.h> -#include <sys/socket.h> -#include <netdb.h> -#include <unistd.h> -#include <errno.h> -#include <osmocom/core/select.h> -#include <osmocom/gsm/gsm_utils.h> -#include <osmocom/hlr/logging.h> -#include <osmocom/mslookup/mdns.h> -#include <osmocom/mslookup/mdns_sock.h> -#include <osmocom/mslookup/mslookup_client.h> -#include <osmocom/mslookup/mslookup_client_mdns.h> - -struct osmo_mdns_method_state { - /* Parameters passed by _add_method_dns() */ - struct osmo_sockaddr_str bind_addr; - const char *domain_suffix; - - struct osmo_mdns_sock *mc; - - struct osmo_mslookup_client *client; - struct llist_head requests; - uint16_t next_packet_id; -}; - -struct osmo_mdns_method_request { - struct llist_head entry; - uint32_t request_handle; - struct osmo_mslookup_query query; - uint16_t packet_id; -}; - -static int request_handle_by_query(uint32_t *request_handle, struct osmo_mdns_method_state *state, - struct osmo_mslookup_query *query, uint16_t packet_id) -{ - struct osmo_mdns_method_request *request; - - llist_for_each_entry(request, &state->requests, entry) { - if (strcmp(request->query.service, query->service) != 0) - continue; - if (osmo_mslookup_id_cmp(&request->query.id, &query->id) != 0) - continue; - - /* Match! */ - *request_handle = request->request_handle; - return 0; - } - return -1; -} - -static int mdns_method_recv(struct osmo_fd *osmo_fd, unsigned int what) -{ - struct osmo_mdns_method_state *state = osmo_fd->data; - struct osmo_mslookup_result result; - struct osmo_mslookup_query query; - uint16_t packet_id; - int n; - uint8_t buffer[1024]; - uint32_t request_handle = 0; - void *ctx = state; - - n = read(osmo_fd->fd, buffer, sizeof(buffer)); - if (n < 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "failed to read from socket\n"); - return n; - } - - if (osmo_mdns_result_decode(ctx, buffer, n, &packet_id, &query, &result, state->domain_suffix) < 0) - return -EINVAL; - - if (request_handle_by_query(&request_handle, state, &query, packet_id) != 0) - return -EINVAL; - - osmo_mslookup_client_rx_result(state->client, request_handle, &result); - return n; -} - -static void mdns_method_request(struct osmo_mslookup_client_method *method, const struct osmo_mslookup_query *query, - uint32_t request_handle) -{ - char buf[256]; - struct osmo_mdns_method_state *state = method->priv; - struct msgb *msg; - struct osmo_mdns_method_request *r = talloc_zero(method->client, struct osmo_mdns_method_request); - - *r = (struct osmo_mdns_method_request){ - .request_handle = request_handle, - .query = *query, - .packet_id = state->next_packet_id, - }; - llist_add(&r->entry, &state->requests); - state->next_packet_id++; - - msg = osmo_mdns_query_encode(method->client, r->packet_id, query, state->domain_suffix); - if (!msg) { - LOGP(DMSLOOKUP, LOGL_ERROR, "Cannot encode request: %s\n", - osmo_mslookup_result_name_b(buf, sizeof(buf), query, NULL)); - } - - /* Send over the wire */ - LOGP(DMSLOOKUP, LOGL_DEBUG, "sending mDNS query: %s.%s\n", query->service, - osmo_mslookup_id_name_b(buf, sizeof(buf), &query->id)); - if (osmo_mdns_sock_send(state->mc, msg) == -1) - LOGP(DMSLOOKUP, LOGL_ERROR, "sending mDNS query failed\n"); -} - -static void mdns_method_request_cleanup(struct osmo_mslookup_client_method *method, uint32_t request_handle) -{ - struct osmo_mdns_method_state *state = method->priv; - - /* Tear down any state associated with this handle. */ - struct osmo_mdns_method_request *r; - llist_for_each_entry(r, &state->requests, entry) { - if (r->request_handle != request_handle) - continue; - llist_del(&r->entry); - talloc_free(r); - return; - } -} - -static void mdns_method_destruct(struct osmo_mslookup_client_method *method) -{ - struct osmo_mdns_method_state *state = method->priv; - struct osmo_mdns_method_request *e, *n; - if (!state) - return; - - /* Drop all DNS lookup request state. Triggering a timeout event and cleanup for mslookup client users will - * happen in the mslookup_client.c, we will simply stop responding from this lookup method. */ - llist_for_each_entry_safe(e, n, &state->requests, entry) { - llist_del(&e->entry); - } - - osmo_mdns_sock_cleanup(state->mc); -} - -/*! Initialize the mDNS lookup method. - * \param[in] client the client to attach the method to. - * \param[in] ip IPv4 or IPv6 address string. - * \param[in] port The port to bind to. - * \param[in] initial_packet_id Used in the first mslookup query, then increased by one in each following query. All - * servers answer to each query with the same packet ID. Set to -1 to use a random - * initial ID (recommended unless you need deterministic output). This ID is for visually - * distinguishing the packets in packet sniffers, the mslookup client uses not just the - * ID, but all query parameters (service type, ID, ID type), to determine if a reply is - * relevant. - * \param[in] domain_suffix is appended to each domain in the queries to avoid colliding with the top-level domains - * administrated by IANA. Example: "mdns.osmocom.org" */ -struct osmo_mslookup_client_method *osmo_mslookup_client_add_mdns(struct osmo_mslookup_client *client, const char *ip, - uint16_t port, int initial_packet_id, - const char *domain_suffix) -{ - struct osmo_mdns_method_state *state; - struct osmo_mslookup_client_method *m; - - m = talloc_zero(client, struct osmo_mslookup_client_method); - OSMO_ASSERT(m); - - state = talloc_zero(m, struct osmo_mdns_method_state); - OSMO_ASSERT(state); - INIT_LLIST_HEAD(&state->requests); - if (osmo_sockaddr_str_from_str(&state->bind_addr, ip, port)) { - LOGP(DMSLOOKUP, LOGL_ERROR, "mslookup mDNS: invalid address/port: %s %u\n", - ip, port); - goto error_cleanup; - } - - if (initial_packet_id == -1) { - if (osmo_get_rand_id((uint8_t *)&state->next_packet_id, 2) < 0) { - LOGP(DMSLOOKUP, LOGL_ERROR, "mslookup mDNS: failed to generate random initial packet ID\n"); - goto error_cleanup; - } - } else - state->next_packet_id = initial_packet_id; - - state->client = client; - state->domain_suffix = domain_suffix; - - state->mc = osmo_mdns_sock_init(state, ip, port, mdns_method_recv, state, 0); - if (!state->mc) - goto error_cleanup; - - *m = (struct osmo_mslookup_client_method){ - .name = "mDNS", - .priv = state, - .request = mdns_method_request, - .request_cleanup = mdns_method_request_cleanup, - .destruct = mdns_method_destruct, - }; - - osmo_mslookup_client_method_add(client, m); - return m; - -error_cleanup: - talloc_free(m); - return NULL; -} - -const struct osmo_sockaddr_str *osmo_mslookup_client_method_mdns_get_bind_addr(struct osmo_mslookup_client_method *dns_method) -{ - struct osmo_mdns_method_state *state; - if (!dns_method || !dns_method->priv) - return NULL; - state = dns_method->priv; - return &state->bind_addr; -} - -const char *osmo_mslookup_client_method_mdns_get_domain_suffix(struct osmo_mslookup_client_method *dns_method) -{ - struct osmo_mdns_method_state *state; - if (!dns_method || !dns_method->priv) - return NULL; - state = dns_method->priv; - return state->domain_suffix; -} |