diff options
author | Daniel Wagner <daniel.wagner@bmw-carit.de> | 2011-01-26 09:50:29 +0100 |
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committer | Marcel Holtmann <marcel@holtmann.org> | 2011-01-26 09:55:18 +0100 |
commit | 01694dcca9cae3efa643126849e068fb2029c6b4 (patch) | |
tree | 15abd9f63d3f37e1133a91d45eb20ea08c9596d3 /plugins | |
parent | cdbacb918f7ec9a8562da4153173b80994e9a40c (diff) | |
download | connman-01694dcca9cae3efa643126849e068fb2029c6b4.tar.gz connman-01694dcca9cae3efa643126849e068fb2029c6b4.tar.bz2 connman-01694dcca9cae3efa643126849e068fb2029c6b4.zip |
dnsproxy: Move from plugins to core
Diffstat (limited to 'plugins')
-rw-r--r-- | plugins/dnsproxy.c | 1517 |
1 files changed, 0 insertions, 1517 deletions
diff --git a/plugins/dnsproxy.c b/plugins/dnsproxy.c deleted file mode 100644 index 60b7a394..00000000 --- a/plugins/dnsproxy.c +++ /dev/null @@ -1,1517 +0,0 @@ -/* - * - * Connection Manager - * - * Copyright (C) 2007-2010 Intel Corporation. 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 version 2 as - * published by the Free Software Foundation. - * - * 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, write to the Free Software - * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - * - */ - -#ifdef HAVE_CONFIG_H -#include <config.h> -#endif - -#include <errno.h> -#include <unistd.h> -#include <string.h> -#include <stdint.h> -#include <arpa/inet.h> -#include <netinet/in.h> -#include <sys/types.h> -#include <sys/socket.h> -#include <netdb.h> - -#define CONNMAN_API_SUBJECT_TO_CHANGE -#include <connman/plugin.h> -#include <connman/resolver.h> -#include <connman/notifier.h> -#include <connman/ondemand.h> -#include <connman/log.h> - -#include <glib.h> - -#if __BYTE_ORDER == __LITTLE_ENDIAN -struct domain_hdr { - uint16_t id; - uint8_t rd:1; - uint8_t tc:1; - uint8_t aa:1; - uint8_t opcode:4; - uint8_t qr:1; - uint8_t rcode:4; - uint8_t z:3; - uint8_t ra:1; - uint16_t qdcount; - uint16_t ancount; - uint16_t nscount; - uint16_t arcount; -} __attribute__ ((packed)); -#elif __BYTE_ORDER == __BIG_ENDIAN -struct domain_hdr { - uint16_t id; - uint8_t qr:1; - uint8_t opcode:4; - uint8_t aa:1; - uint8_t tc:1; - uint8_t rd:1; - uint8_t ra:1; - uint8_t z:3; - uint8_t rcode:4; - uint16_t qdcount; - uint16_t ancount; - uint16_t nscount; - uint16_t arcount; -} __attribute__ ((packed)); -#else -#error "Unknown byte order" -#endif - -struct partial_reply { - uint16_t len; - uint16_t received; - unsigned char buf[]; -}; - -struct server_data { - char *interface; - GList *domains; - char *server; - int protocol; - GIOChannel *channel; - guint watch; - guint timeout; - gboolean enabled; - gboolean connected; - struct partial_reply *incoming_reply; -}; - -struct request_data { - union { - struct sockaddr_in6 __sin6; /* Only for the length */ - struct sockaddr sa; - }; - socklen_t sa_len; - int client_sk; - int protocol; - guint16 srcid; - guint16 dstid; - guint16 altid; - guint timeout; - guint watch; - guint numserv; - guint numresp; - gpointer request; - gsize request_len; - gpointer name; - gpointer resp; - gsize resplen; -}; - -static GSList *server_list = NULL; -static GSList *request_list = NULL; -static GSList *request_pending_list = NULL; -static guint16 request_id = 0x0000; - -static GIOChannel *udp_listener_channel = NULL; -static guint udp_listener_watch = 0; -static GIOChannel *tcp_listener_channel = NULL; -static guint tcp_listener_watch = 0; - -static int protocol_offset(int protocol) -{ - switch (protocol) { - case IPPROTO_UDP: - return 0; - - case IPPROTO_TCP: - return 2; - - default: - return -EINVAL; - } - -} - -static struct request_data *find_request(guint16 id) -{ - GSList *list; - - for (list = request_list; list; list = list->next) { - struct request_data *req = list->data; - - if (req->dstid == id || req->altid == id) - return req; - } - - return NULL; -} - -static struct server_data *find_server(const char *interface, - const char *server, - int protocol) -{ - GSList *list; - - DBG("interface %s server %s", interface, server); - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - - if (data->interface == NULL || data->server == NULL) - continue; - - if (g_str_equal(data->interface, interface) == TRUE && - g_str_equal(data->server, server) == TRUE && - data->protocol == protocol) - return data; - } - - return NULL; -} - - -static void send_response(int sk, unsigned char *buf, int len, - const struct sockaddr *to, socklen_t tolen, - int protocol) -{ - struct domain_hdr *hdr; - int err, offset = protocol_offset(protocol); - - DBG(""); - - if (offset < 0) - return; - - if (len < 12) - return; - - hdr = (void*) (buf + offset); - - DBG("id 0x%04x qr %d opcode %d", hdr->id, hdr->qr, hdr->opcode); - - hdr->qr = 1; - hdr->rcode = 2; - - hdr->ancount = 0; - hdr->nscount = 0; - hdr->arcount = 0; - - err = sendto(sk, buf, len, 0, to, tolen); -} - -static gboolean request_timeout(gpointer user_data) -{ - struct request_data *req = user_data; - - DBG("id 0x%04x", req->srcid); - - if (req == NULL) - return FALSE; - - request_list = g_slist_remove(request_list, req); - req->numserv--; - - if (req->resplen > 0 && req->resp != NULL) { - int sk, err; - - sk = g_io_channel_unix_get_fd(udp_listener_channel); - - err = sendto(sk, req->resp, req->resplen, 0, - &req->sa, req->sa_len); - } else if (req->request && req->numserv == 0) { - struct domain_hdr *hdr; - - if (req->protocol == IPPROTO_TCP) { - hdr = (void *) (req->request + 2); - hdr->id = req->srcid; - send_response(req->client_sk, req->request, - req->request_len, NULL, 0, IPPROTO_TCP); - - } else if (req->protocol == IPPROTO_UDP) { - int sk; - - hdr = (void *) (req->request); - hdr->id = req->srcid; - sk = g_io_channel_unix_get_fd(udp_listener_channel); - send_response(sk, req->request, req->request_len, - &req->sa, req->sa_len, IPPROTO_UDP); - } - } - - g_free(req->resp); - g_free(req); - - return FALSE; -} - -static int append_query(unsigned char *buf, unsigned int size, - const char *query, const char *domain) -{ - unsigned char *ptr = buf; - char *offset; - - DBG("query %s domain %s", query, domain); - - offset = (char *) query; - while (offset != NULL) { - char *tmp; - - tmp = strchr(offset, '.'); - if (tmp == NULL) { - if (strlen(offset) == 0) - break; - *ptr = strlen(offset); - memcpy(ptr + 1, offset, strlen(offset)); - ptr += strlen(offset) + 1; - break; - } - - *ptr = tmp - offset; - memcpy(ptr + 1, offset, tmp - offset); - ptr += tmp - offset + 1; - - offset = tmp + 1; - } - - offset = (char *) domain; - while (offset != NULL) { - char *tmp; - - tmp = strchr(offset, '.'); - if (tmp == NULL) { - if (strlen(offset) == 0) - break; - *ptr = strlen(offset); - memcpy(ptr + 1, offset, strlen(offset)); - ptr += strlen(offset) + 1; - break; - } - - *ptr = tmp - offset; - memcpy(ptr + 1, offset, tmp - offset); - ptr += tmp - offset + 1; - - offset = tmp + 1; - } - - *ptr++ = 0x00; - - return ptr - buf; -} - -static int ns_resolv(struct server_data *server, struct request_data *req, - gpointer request, gpointer name) -{ - GList *list; - int sk, err; - - sk = g_io_channel_unix_get_fd(server->channel); - - err = send(sk, request, req->request_len, 0); - - req->numserv++; - - for (list = server->domains; list; list = list->next) { - char *domain; - unsigned char alt[1024]; - struct domain_hdr *hdr = (void *) &alt; - int altlen, domlen, offset; - - domain = list->data; - - if (domain == NULL) - continue; - - offset = protocol_offset(server->protocol); - if (offset < 0) - return offset; - - domlen = strlen(domain) + 1; - if (domlen < 5) - return -EINVAL; - - alt[offset] = req->altid & 0xff; - alt[offset + 1] = req->altid >> 8; - - memcpy(alt + offset + 2, request + offset + 2, 10); - hdr->qdcount = htons(1); - - altlen = append_query(alt + offset + 12, sizeof(alt) - 12, - name, domain); - if (altlen < 0) - return -EINVAL; - - altlen += 12; - - memcpy(alt + offset + altlen, - request + offset + altlen - domlen, - req->request_len - altlen + domlen); - - if (server->protocol == IPPROTO_TCP) { - int req_len = req->request_len + domlen - 1; - - alt[0] = (req_len >> 8) & 0xff; - alt[1] = req_len & 0xff; - } - - err = send(sk, alt, req->request_len + domlen + 1, 0); - - req->numserv++; - } - - return 0; -} - -static int forward_dns_reply(unsigned char *reply, int reply_len, int protocol) -{ - struct domain_hdr *hdr; - struct request_data *req; - int dns_id, sk, err, offset = protocol_offset(protocol); - - if (offset < 0) - return offset; - - hdr = (void *)(reply + offset); - dns_id = reply[offset] | reply[offset + 1] << 8; - - DBG("Received %d bytes (id 0x%04x)", reply_len, dns_id); - - req = find_request(dns_id); - if (req == NULL) - return -EINVAL; - - DBG("id 0x%04x rcode %d", hdr->id, hdr->rcode); - - reply[offset] = req->srcid & 0xff; - reply[offset + 1] = req->srcid >> 8; - - req->numresp++; - - if (hdr->rcode == 0 || req->resp == NULL) { - g_free(req->resp); - req->resplen = 0; - - req->resp = g_try_malloc(reply_len); - if (req->resp == NULL) - return -ENOMEM; - - memcpy(req->resp, reply, reply_len); - req->resplen = reply_len; - } - - if (hdr->rcode > 0 && req->numresp < req->numserv) - return -EINVAL; - - if (req->timeout > 0) - g_source_remove(req->timeout); - - request_list = g_slist_remove(request_list, req); - - if (protocol == IPPROTO_UDP) { - sk = g_io_channel_unix_get_fd(udp_listener_channel); - err = sendto(sk, req->resp, req->resplen, 0, - &req->sa, req->sa_len); - } else { - sk = req->client_sk; - err = send(sk, req->resp, req->resplen, 0); - close(sk); - } - - g_free(req->resp); - g_free(req); - - return err; -} - -static void destroy_server(struct server_data *server) -{ - GList *list; - - DBG("interface %s server %s", server->interface, server->server); - - server_list = g_slist_remove(server_list, server); - - if (server->watch > 0) - g_source_remove(server->watch); - - if (server->timeout > 0) - g_source_remove(server->timeout); - - g_io_channel_unref(server->channel); - - if (server->protocol == IPPROTO_UDP) - connman_info("Removing DNS server %s", server->server); - - g_free(server->incoming_reply); - g_free(server->server); - for (list = server->domains; list; list = list->next) { - char *domain = list->data; - - server->domains = g_list_remove(server->domains, domain); - g_free(domain); - } - g_free(server->interface); - g_free(server); -} - -static gboolean udp_server_event(GIOChannel *channel, GIOCondition condition, - gpointer user_data) -{ - unsigned char buf[4096]; - int sk, err, len; - - if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) { - struct server_data *data = user_data; - - connman_error("Error with UDP server %s", data->server); - data->watch = 0; - return FALSE; - } - - sk = g_io_channel_unix_get_fd(channel); - - len = recv(sk, buf, sizeof(buf), 0); - if (len < 12) - return TRUE; - - err = forward_dns_reply(buf, len, IPPROTO_UDP); - - return TRUE; -} - -static gboolean tcp_server_event(GIOChannel *channel, GIOCondition condition, - gpointer user_data) -{ - int sk; - struct server_data *server = user_data; - - sk = g_io_channel_unix_get_fd(channel); - if (sk == 0) - return FALSE; - - if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) { - GSList *list; - hangup: - DBG("TCP server channel closed"); - - /* - * Discard any partial response which is buffered; better - * to get a proper response from a working server. - */ - g_free(server->incoming_reply); - server->incoming_reply = NULL; - - for (list = request_list; list; list = list->next) { - struct request_data *req = list->data; - struct domain_hdr *hdr; - - if (req->protocol == IPPROTO_UDP) - continue; - - if (req->request == NULL) - continue; - - /* - * If we're not waiting for any further response - * from another name server, then we send an error - * response to the client. - */ - if (req->numserv && --(req->numserv)) - continue; - - hdr = (void *) (req->request + 2); - hdr->id = req->srcid; - send_response(req->client_sk, req->request, - req->request_len, NULL, 0, IPPROTO_TCP); - - request_list = g_slist_remove(request_list, req); - } - - destroy_server(server); - - return FALSE; - } - - if ((condition & G_IO_OUT) && !server->connected) { - GSList *list; - GList *domains; - struct server_data *udp_server; - - udp_server = find_server(server->interface, server->server, - IPPROTO_UDP); - if (udp_server != NULL) { - for (domains = udp_server->domains; domains; - domains = domains->next) { - char *dom = domains->data; - - DBG("Adding domain %s to %s", - dom, server->server); - - server->domains = g_list_append(server->domains, - g_strdup(dom)); - } - } - - server->connected = TRUE; - server_list = g_slist_append(server_list, server); - - if (server->timeout > 0) { - g_source_remove(server->timeout); - server->timeout = 0; - } - - for (list = request_list; list; list = list->next) { - struct request_data *req = list->data; - - if (req->protocol == IPPROTO_UDP) - continue; - - DBG("Sending req %s over TCP", (char *)req->name); - - if (req->timeout > 0) - g_source_remove(req->timeout); - - req->timeout = g_timeout_add_seconds(30, - request_timeout, req); - ns_resolv(server, req, req->request, req->name); - } - - } else if (condition & G_IO_IN) { - struct partial_reply *reply = server->incoming_reply; - int bytes_recv; - - if (!reply) { - unsigned char reply_len_buf[2]; - uint16_t reply_len; - - bytes_recv = recv(sk, reply_len_buf, 2, MSG_PEEK); - if (!bytes_recv) { - goto hangup; - } else if (bytes_recv < 0) { - if (errno == EAGAIN || errno == EWOULDBLOCK) - return TRUE; - - connman_error("DNS proxy error %s", - strerror(errno)); - goto hangup; - } else if (bytes_recv < 2) - return TRUE; - - reply_len = reply_len_buf[1] | reply_len_buf[0] << 8; - reply_len += 2; - - DBG("TCP reply %d bytes", reply_len); - - reply = g_try_malloc(sizeof(*reply) + reply_len + 2); - if (!reply) - return TRUE; - - reply->len = reply_len; - reply->received = 0; - - server->incoming_reply = reply; - } - - while (reply->received < reply->len) { - bytes_recv = recv(sk, reply->buf + reply->received, - reply->len - reply->received, 0); - if (!bytes_recv) { - connman_error("DNS proxy TCP disconnect"); - break; - } else if (bytes_recv < 0) { - if (errno == EAGAIN || errno == EWOULDBLOCK) - return TRUE; - - connman_error("DNS proxy error %s", - strerror(errno)); - break; - } - reply->received += bytes_recv; - } - - forward_dns_reply(reply->buf, reply->received, IPPROTO_TCP); - - g_free(reply); - server->incoming_reply = NULL; - - destroy_server(server); - - return FALSE; - } - - return TRUE; -} - -static gboolean tcp_idle_timeout(gpointer user_data) -{ - struct server_data *server = user_data; - - DBG(""); - - if (server == NULL) - return FALSE; - - destroy_server(server); - - return FALSE; -} - -static struct server_data *create_server(const char *interface, - const char *domain, const char *server, - int protocol) -{ - struct addrinfo hints, *rp; - struct server_data *data; - int sk, ret; - - DBG("interface %s server %s", interface, server); - - memset(&hints, 0, sizeof(hints)); - - switch (protocol) { - case IPPROTO_UDP: - hints.ai_socktype = SOCK_DGRAM; - break; - - case IPPROTO_TCP: - hints.ai_socktype = SOCK_STREAM; - break; - - default: - return NULL; - } - hints.ai_family = AF_UNSPEC; - hints.ai_flags = AI_PASSIVE | AI_NUMERICSERV | AI_NUMERICHOST; - - ret = getaddrinfo(server, "53", &hints, &rp); - if (ret) { - connman_error("Failed to parse server %s address: %s\n", - server, gai_strerror(ret)); - return NULL; - } - /* Do not blindly copy this code elsewhere; it doesn't loop over the - results using ->ai_next as it should. That's OK in *this* case - because it was a numeric lookup; we *know* there's only one. */ - - sk = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol); - if (sk < 0) { - connman_error("Failed to create server %s socket", server); - freeaddrinfo(rp); - return NULL; - } - - if (interface != NULL) { - if (setsockopt(sk, SOL_SOCKET, SO_BINDTODEVICE, - interface, strlen(interface) + 1) < 0) { - connman_error("Failed to bind server %s " - "to interface %s", - server, interface); - freeaddrinfo(rp); - close(sk); - return NULL; - } - } - - data = g_try_new0(struct server_data, 1); - if (data == NULL) { - connman_error("Failed to allocate server %s data", server); - freeaddrinfo(rp); - close(sk); - return NULL; - } - - data->channel = g_io_channel_unix_new(sk); - if (data->channel == NULL) { - connman_error("Failed to create server %s channel", server); - freeaddrinfo(rp); - close(sk); - g_free(data); - return NULL; - } - - g_io_channel_set_close_on_unref(data->channel, TRUE); - - if (protocol == IPPROTO_TCP) { - g_io_channel_set_flags(data->channel, G_IO_FLAG_NONBLOCK, NULL); - data->watch = g_io_add_watch(data->channel, - G_IO_OUT | G_IO_IN | G_IO_HUP | G_IO_NVAL | G_IO_ERR, - tcp_server_event, data); - data->timeout = g_timeout_add_seconds(30, tcp_idle_timeout, - data); - } else - data->watch = g_io_add_watch(data->channel, - G_IO_IN | G_IO_NVAL | G_IO_ERR | G_IO_HUP, - udp_server_event, data); - - data->interface = g_strdup(interface); - if (domain) - data->domains = g_list_append(data->domains, g_strdup(domain)); - data->server = g_strdup(server); - data->protocol = protocol; - - ret = connect(sk, rp->ai_addr, rp->ai_addrlen); - freeaddrinfo(rp); - if (ret < 0) { - if ((protocol == IPPROTO_TCP && errno != EINPROGRESS) || - protocol == IPPROTO_UDP) { - GList *list; - - connman_error("Failed to connect to server %s", server); - if (data->watch > 0) - g_source_remove(data->watch); - if (data->timeout > 0) - g_source_remove(data->timeout); - - g_io_channel_unref(data->channel); - close(sk); - - g_free(data->server); - g_free(data->interface); - for (list = data->domains; list; list = list->next) { - char *domain = list->data; - - data->domains = g_list_remove(data->domains, - domain); - g_free(domain); - } - g_free(data); - return NULL; - } - } - - if (protocol == IPPROTO_UDP) { - /* Enable new servers by default */ - data->enabled = TRUE; - connman_info("Adding DNS server %s", data->server); - - server_list = g_slist_append(server_list, data); - - return data; - } - - return NULL; -} - -static gboolean resolv(struct request_data *req, - gpointer request, gpointer name) -{ - GSList *list; - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - - DBG("server %s enabled %d", data->server, data->enabled); - - if (data->enabled == FALSE) - continue; - - if (data->watch == 0 && data->protocol == IPPROTO_UDP) - data->watch = g_io_add_watch(data->channel, - G_IO_IN | G_IO_NVAL | G_IO_ERR | G_IO_HUP, - udp_server_event, data); - - if (ns_resolv(data, req, request, name) < 0) - continue; - } - - return TRUE; -} - -static void append_domain(const char *interface, const char *domain) -{ - GSList *list; - - DBG("interface %s domain %s", interface, domain); - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - GList *dom_list; - char *dom; - gboolean dom_found = FALSE; - - if (data->interface == NULL) - continue; - - if (g_str_equal(data->interface, interface) == FALSE) - continue; - - for (dom_list = data->domains; dom_list; dom_list = dom_list->next) { - dom = dom_list->data; - - if (g_str_equal(dom, domain)) { - dom_found = TRUE; - break; - } - } - - if (dom_found == FALSE) - data->domains = g_list_append(data->domains, g_strdup(domain)); - } -} - -static int dnsproxy_append(const char *interface, const char *domain, - const char *server) -{ - struct server_data *data; - - DBG("interface %s server %s", interface, server); - - if (server == NULL && domain == NULL) - return -EINVAL; - - if (server == NULL) { - append_domain(interface, domain); - - return 0; - } - - if (g_str_equal(server, "127.0.0.1") == TRUE) - return -ENODEV; - - data = find_server(interface, server, IPPROTO_UDP); - if (data != NULL) { - append_domain(interface, domain); - return 0; - } - - data = create_server(interface, domain, server, IPPROTO_UDP); - if (data == NULL) - return -EIO; - - return 0; -} - -static void remove_server(const char *interface, const char *domain, - const char *server, int protocol) -{ - struct server_data *data; - - data = find_server(interface, server, protocol); - if (data == NULL) - return; - - destroy_server(data); -} - -static int dnsproxy_remove(const char *interface, const char *domain, - const char *server) -{ - DBG("interface %s server %s", interface, server); - - if (server == NULL) - return -EINVAL; - - if (g_str_equal(server, "127.0.0.1") == TRUE) - return -ENODEV; - - remove_server(interface, domain, server, IPPROTO_UDP); - remove_server(interface, domain, server, IPPROTO_TCP); - - return 0; -} - -static void dnsproxy_flush(void) -{ - GSList *list; - - list = request_pending_list; - while (list) { - struct request_data *req = list->data; - - list = list->next; - - request_pending_list = - g_slist_remove(request_pending_list, req); - resolv(req, req->request, req->name); - g_free(req->request); - g_free(req->name); - } -} - -static struct connman_resolver dnsproxy_resolver = { - .name = "dnsproxy", - .priority = CONNMAN_RESOLVER_PRIORITY_HIGH, - .append = dnsproxy_append, - .remove = dnsproxy_remove, - .flush = dnsproxy_flush, -}; - -static void dnsproxy_offline_mode(connman_bool_t enabled) -{ - GSList *list; - - DBG("enabled %d", enabled); - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - - if (enabled == FALSE) { - connman_info("Enabling DNS server %s", data->server); - data->enabled = TRUE; - } else { - connman_info("Disabling DNS server %s", data->server); - data->enabled = FALSE; - } - } -} - -static void dnsproxy_default_changed(struct connman_service *service) -{ - GSList *list; - char *interface; - - DBG("service %p", service); - - if (service == NULL) { - /* When no services are active, then disable DNS proxying */ - dnsproxy_offline_mode(TRUE); - return; - } - - interface = connman_service_get_interface(service); - if (interface == NULL) - return; - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - - if (g_strcmp0(data->interface, interface) == 0) { - connman_info("Enabling DNS server %s", data->server); - data->enabled = TRUE; - } else { - connman_info("Disabling DNS server %s", data->server); - data->enabled = FALSE; - } - } - - g_free(interface); -} - -static struct connman_notifier dnsproxy_notifier = { - .name = "dnsproxy", - .default_changed = dnsproxy_default_changed, - .offline_mode = dnsproxy_offline_mode, -}; - -static unsigned char opt_edns0_type[2] = { 0x00, 0x29 }; - -static int parse_request(unsigned char *buf, int len, - char *name, unsigned int size) -{ - struct domain_hdr *hdr = (void *) buf; - uint16_t qdcount = ntohs(hdr->qdcount); - uint16_t arcount = ntohs(hdr->arcount); - unsigned char *ptr; - char *last_label = NULL; - unsigned int remain, used = 0; - - if (len < 12) - return -EINVAL; - - DBG("id 0x%04x qr %d opcode %d qdcount %d arcount %d", - hdr->id, hdr->qr, hdr->opcode, - qdcount, arcount); - - if (hdr->qr != 0 || qdcount != 1) - return -EINVAL; - - memset(name, 0, size); - - ptr = buf + sizeof(struct domain_hdr); - remain = len - sizeof(struct domain_hdr); - - while (remain > 0) { - uint8_t len = *ptr; - - if (len == 0x00) { - last_label = (char *) (ptr + 1); - break; - } - - if (used + len + 1 > size) - return -ENOBUFS; - - strncat(name, (char *) (ptr + 1), len); - strcat(name, "."); - - used += len + 1; - - ptr += len + 1; - remain -= len + 1; - } - - if (last_label && arcount && remain >= 9 && last_label[4] == 0 && - !memcmp(last_label + 5, opt_edns0_type, 2)) { - uint16_t edns0_bufsize; - - edns0_bufsize = last_label[7] << 8 | last_label[8]; - - DBG("EDNS0 buffer size %u", edns0_bufsize); - - /* This is an evil hack until full TCP support has been - * implemented. - * - * Somtimes the EDNS0 request gets send with a too-small - * buffer size. Since glibc doesn't seem to crash when it - * gets a response biffer then it requested, just bump - * the buffer size up to 4KiB. - */ - if (edns0_bufsize < 0x1000) { - last_label[7] = 0x10; - last_label[8] = 0x00; - } - } - - DBG("query %s", name); - - return 0; -} - -static gboolean tcp_listener_event(GIOChannel *channel, GIOCondition condition, - gpointer user_data) -{ - unsigned char buf[768]; - char query[512]; - struct request_data *req; - struct server_data *server; - int sk, client_sk, len, err; - struct sockaddr_in6 client_addr; - socklen_t client_addr_len = sizeof(client_addr); - GSList *list; - - DBG("condition 0x%x", condition); - - if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) { - if (tcp_listener_watch > 0) - g_source_remove(tcp_listener_watch); - tcp_listener_watch = 0; - - connman_error("Error with TCP listener channel"); - - return FALSE; - } - - sk = g_io_channel_unix_get_fd(channel); - - client_sk = accept(sk, (void *)&client_addr, &client_addr_len); - if (client_sk < 0) { - connman_error("Accept failure on TCP listener"); - tcp_listener_watch = 0; - return FALSE; - } - - len = recv(client_sk, buf, sizeof(buf), 0); - if (len < 2) - return TRUE; - - DBG("Received %d bytes (id 0x%04x)", len, buf[2] | buf[3] << 8); - - err = parse_request(buf + 2, len - 2, query, sizeof(query)); - if (err < 0 || (g_slist_length(server_list) == 0 && - connman_ondemand_connected())) { - send_response(client_sk, buf, len, NULL, 0, IPPROTO_TCP); - return TRUE; - } - - req = g_try_new0(struct request_data, 1); - if (req == NULL) - return TRUE; - - memcpy(&req->sa, &client_addr, client_addr_len); - req->sa_len = client_addr_len; - req->client_sk = client_sk; - req->protocol = IPPROTO_TCP; - - request_id += 2; - if (request_id == 0x0000 || request_id == 0xffff) - request_id += 2; - - req->srcid = buf[2] | (buf[3] << 8); - req->dstid = request_id; - req->altid = request_id + 1; - req->request_len = len; - - buf[2] = req->dstid & 0xff; - buf[3] = req->dstid >> 8; - - req->numserv = 0; - request_list = g_slist_append(request_list, req); - - for (list = server_list; list; list = list->next) { - struct server_data *data = list->data; - GList *domains; - - if (data->protocol != IPPROTO_UDP || data->enabled == FALSE) - continue; - - server = create_server(data->interface, NULL, - data->server, IPPROTO_TCP); - - /* - * If server is NULL, we're not connected yet. - * Copy the relevant buffers and continue with - * the next nameserver. - * The request will actually be sent once we're - * properly connected over TCP to this nameserver. - */ - if (server == NULL) { - req->request = g_try_malloc0(req->request_len); - if (req->request == NULL) - return TRUE; - - memcpy(req->request, buf, req->request_len); - - req->name = g_try_malloc0(sizeof(query)); - if (req->name == NULL) { - g_free(req->request); - return TRUE; - } - memcpy(req->name, query, sizeof(query)); - - continue; - } - - if (req->timeout > 0) - g_source_remove(req->timeout); - - for (domains = data->domains; domains; domains = domains->next) { - char *dom = domains->data; - - DBG("Adding domain %s to %s", dom, server->server); - - server->domains = g_list_append(server->domains, - g_strdup(dom)); - } - - req->timeout = g_timeout_add_seconds(30, request_timeout, req); - ns_resolv(server, req, buf, query); - } - - return TRUE; -} - -static gboolean udp_listener_event(GIOChannel *channel, GIOCondition condition, - gpointer user_data) -{ - unsigned char buf[768]; - char query[512]; - struct request_data *req; - struct sockaddr_in6 client_addr; - socklen_t client_addr_len = sizeof(client_addr); - int sk, err, len; - - if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) { - connman_error("Error with UDP listener channel"); - udp_listener_watch = 0; - return FALSE; - } - - sk = g_io_channel_unix_get_fd(channel); - - memset(&client_addr, 0, client_addr_len); - len = recvfrom(sk, buf, sizeof(buf), 0, (void *)&client_addr, - &client_addr_len); - if (len < 2) - return TRUE; - - DBG("Received %d bytes (id 0x%04x)", len, buf[0] | buf[1] << 8); - - err = parse_request(buf, len, query, sizeof(query)); - if (err < 0 || (g_slist_length(server_list) == 0 && - connman_ondemand_connected())) { - send_response(sk, buf, len, (void *)&client_addr, - client_addr_len, IPPROTO_UDP); - return TRUE; - } - - req = g_try_new0(struct request_data, 1); - if (req == NULL) - return TRUE; - - memcpy(&req->sa, &client_addr, client_addr_len); - req->sa_len = client_addr_len; - req->client_sk = 0; - req->protocol = IPPROTO_UDP; - - request_id += 2; - if (request_id == 0x0000 || request_id == 0xffff) - request_id += 2; - - req->srcid = buf[0] | (buf[1] << 8); - req->dstid = request_id; - req->altid = request_id + 1; - req->request_len = len; - - buf[0] = req->dstid & 0xff; - buf[1] = req->dstid >> 8; - - if (!connman_ondemand_connected()) { - DBG("Starting on demand connection"); - /* - * We're not connected, let's queue the request and start - * an on-demand connection. - */ - req->request = g_try_malloc0(req->request_len); - if (req->request == NULL) - return TRUE; - - memcpy(req->request, buf, req->request_len); - - req->name = g_try_malloc0(sizeof(query)); - if (req->name == NULL) { - g_free(req->request); - return TRUE; - } - memcpy(req->name, query, sizeof(query)); - - request_pending_list = g_slist_append(request_pending_list, - req); - - connman_ondemand_start("", 300); - - return TRUE; - } - - - req->numserv = 0; - req->timeout = g_timeout_add_seconds(5, request_timeout, req); - request_list = g_slist_append(request_list, req); - - return resolv(req, buf, query); -} - -static int create_dns_listener(int protocol) -{ - GIOChannel *channel; - const char *ifname = "lo", *proto; - union { - struct sockaddr sa; - struct sockaddr_in6 sin6; - struct sockaddr_in sin; - } s; - socklen_t slen; - int sk, type, v6only = 0; - int family = AF_INET6; - - DBG(""); - - switch (protocol) { - case IPPROTO_UDP: - proto = "UDP"; - type = SOCK_DGRAM; - break; - - case IPPROTO_TCP: - proto = "TCP"; - type = SOCK_STREAM; - break; - - default: - return -EINVAL; - } - - sk = socket(family, type, protocol); - if (sk < 0 && family == AF_INET6 && errno == EAFNOSUPPORT) { - connman_error("No IPv6 support; DNS proxy listening only on Legacy IP"); - family = AF_INET; - sk = socket(family, type, protocol); - } - if (sk < 0) { - connman_error("Failed to create %s listener socket", proto); - return -EIO; - } - - if (setsockopt(sk, SOL_SOCKET, SO_BINDTODEVICE, - ifname, strlen(ifname) + 1) < 0) { - connman_error("Failed to bind %s listener interface", proto); - close(sk); - return -EIO; - } - /* Ensure it accepts Legacy IP connections too */ - if (family == AF_INET6 && - setsockopt(sk, SOL_IPV6, IPV6_V6ONLY, &v6only, sizeof(v6only)) < 0) { - connman_error("Failed to clear V6ONLY on %s listener socket", - proto); - close(sk); - return -EIO; - } - - if (family == AF_INET) { - memset(&s.sin, 0, sizeof(s.sin)); - s.sin.sin_family = AF_INET; - s.sin.sin_port = htons(53); - s.sin.sin_addr.s_addr = htonl(INADDR_ANY); - slen = sizeof(s.sin); - } else { - memset(&s.sin6, 0, sizeof(s.sin6)); - s.sin6.sin6_family = AF_INET6; - s.sin6.sin6_port = htons(53); - s.sin6.sin6_addr = in6addr_any; - slen = sizeof(s.sin6); - } - - if (bind(sk, &s.sa, slen) < 0) { - connman_error("Failed to bind %s listener socket", proto); - close(sk); - return -EIO; - } - - if (protocol == IPPROTO_TCP && listen(sk, 10) < 0) { - connman_error("Failed to listen on TCP socket"); - close(sk); - return -EIO; - } - - channel = g_io_channel_unix_new(sk); - if (channel == NULL) { - connman_error("Failed to create %s listener channel", proto); - close(sk); - return -EIO; - } - - g_io_channel_set_close_on_unref(channel, TRUE); - - if (protocol == IPPROTO_TCP) { - tcp_listener_channel = channel; - tcp_listener_watch = g_io_add_watch(channel, - G_IO_IN, tcp_listener_event, NULL); - } else { - udp_listener_channel = channel; - udp_listener_watch = g_io_add_watch(channel, - G_IO_IN, udp_listener_event, NULL); - } - - return 0; -} - -static void destroy_udp_listener(void) -{ - DBG(""); - - if (udp_listener_watch > 0) - g_source_remove(udp_listener_watch); - - g_io_channel_unref(udp_listener_channel); -} - -static void destroy_tcp_listener(void) -{ - DBG(""); - - if (tcp_listener_watch > 0) - g_source_remove(tcp_listener_watch); - - g_io_channel_unref(tcp_listener_channel); -} - -static int create_listener(void) -{ - int err; - - err = create_dns_listener(IPPROTO_UDP); - if (err < 0) - return err; - - err = create_dns_listener(IPPROTO_TCP); - if (err < 0) { - destroy_udp_listener(); - return err; - } - - connman_resolver_append("lo", NULL, "127.0.0.1"); - - return 0; -} - -static void destroy_listener(void) -{ - GSList *list; - - connman_resolver_remove_all("lo"); - - for (list = request_pending_list; list; list = list->next) { - struct request_data *req = list->data; - - DBG("Dropping pending request (id 0x%04x -> 0x%04x)", - req->srcid, req->dstid); - - g_free(req->resp); - g_free(req->request); - g_free(req->name); - g_free(req); - list->data = NULL; - } - - g_slist_free(request_pending_list); - request_pending_list = NULL; - - for (list = request_list; list; list = list->next) { - struct request_data *req = list->data; - - DBG("Dropping request (id 0x%04x -> 0x%04x)", - req->srcid, req->dstid); - - g_free(req->resp); - g_free(req->request); - g_free(req->name); - g_free(req); - list->data = NULL; - } - - g_slist_free(request_list); - request_list = NULL; - - destroy_tcp_listener(); - destroy_udp_listener(); -} - -static int dnsproxy_init(void) -{ - int err; - - err = create_listener(); - if (err < 0) - return err; - - err = connman_resolver_register(&dnsproxy_resolver); - if (err < 0) - goto destroy; - - err = connman_notifier_register(&dnsproxy_notifier); - if (err < 0) - goto unregister; - - return 0; - -unregister: - connman_resolver_unregister(&dnsproxy_resolver); - -destroy: - destroy_listener(); - - return err; -} - -static void dnsproxy_exit(void) -{ - connman_notifier_unregister(&dnsproxy_notifier); - - connman_resolver_unregister(&dnsproxy_resolver); - - destroy_listener(); -} - -CONNMAN_PLUGIN_DEFINE(dnsproxy, "DNS proxy resolver plugin", VERSION, - CONNMAN_PLUGIN_PRIORITY_DEFAULT, dnsproxy_init, dnsproxy_exit) |