WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Affero General Public License for more details.
-
+
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+ SPDX-License-Identifier: AGPL3.0-or-later
*/
/**
#include "resolver.h"
-struct Record
+/**
+ * How long do we wait for DNS answers?
+ */
+#define DNS_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
+
+/**
+ * Maximum number of hostnames we cache results for.
+ */
+#define MAX_CACHE 1024
+
+/**
+ * Entry in list of cached DNS records for a hostname.
+ */
+struct RecordListEntry
{
- struct Record *next;
+ /**
+ * This is a doubly linked list.
+ */
+ struct RecordListEntry *next;
- struct Record *prev;
+ /**
+ * This is a doubly linked list.
+ */
+ struct RecordListEntry *prev;
+ /**
+ * Cached data.
+ */
struct GNUNET_DNSPARSER_Record *record;
+
};
+
/**
* A cached DNS lookup result.
*/
struct ResolveCache *prev;
/**
- * type of queried DNS record
+ * Which hostname is this cache for?
*/
- uint16_t record_type;
+ char *hostname;
/**
- * a pointer to the request_id if a query for this hostname/record_type
- * is currently pending, NULL otherwise.
+ * head of a double linked list containing the lookup results
*/
- int16_t *request_id;
+ struct RecordListEntry *records_head;
+
+ /**
+ * tail of a double linked list containing the lookup results
+ */
+ struct RecordListEntry *records_tail;
+
+};
- struct GNUNET_SERVICE_Client *client;
+/**
+ * Information about pending lookups.
+ */
+struct ActiveLookup
+{
/**
- * head of a double linked list containing the lookup results
+ * Stored in a DLL.
*/
- struct Record *records_head;
+ struct ActiveLookup *next;
/**
- * tail of a double linked list containing the lookup results
+ * Stored in a DLL.
*/
- struct Record *records_tail;
+ struct ActiveLookup *prev;
+
+ /**
+ * The client that queried the records contained in this cache entry.
+ */
+ struct GNUNET_SERVICE_Client *client;
/**
* handle for cancelling a request
*/
struct GNUNET_SCHEDULER_Task *timeout_task;
+ /**
+ * Which hostname are we resolving?
+ */
+ char *hostname;
+
+ /**
+ * If @a record_type is #GNUNET_DNSPARSER_TYPE_ALL, did we go again
+ * for the AAAA records yet?
+ */
+ int did_aaaa;
+
+ /**
+ * type of queried DNS record
+ */
+ uint16_t record_type;
+
+ /**
+ * Unique request ID of a client if a query for this hostname/record_type
+ * is currently pending, undefined otherwise.
+ */
+ uint32_t client_request_id;
+
+ /**
+ * Unique DNS request ID of a client if a query for this hostname/record_type
+ * is currently pending, undefined otherwise.
+ */
+ uint16_t dns_id;
+
};
*/
static struct ResolveCache *cache_tail;
+/**
+ * Head of the linked list of DNS lookup results from /etc/hosts.
+ */
+static struct ResolveCache *hosts_head;
+
+/**
+ * Tail of the linked list of DNS lookup results from /etc/hosts.
+ */
+static struct ResolveCache *hosts_tail;
+
+/**
+ * Start of the linked list of active DNS lookups.
+ */
+static struct ActiveLookup *lookup_head;
+
+/**
+ * Tail of the linked list of active DNS lookups.
+ */
+static struct ActiveLookup *lookup_tail;
+
/**
* context of dnsstub library
*/
static struct GNUNET_DNSSTUB_Context *dnsstub_ctx;
+/**
+ * My domain, to be appended to the hostname to get a FQDN.
+ */
+static char *my_domain;
+
+/**
+ * How many entries do we have in #cache_head DLL?
+ */
+static unsigned int cache_size;
+
-void free_cache_entry (struct ResolveCache *entry)
+/**
+ * Remove @a entry from cache.
+ *
+ * @param rc entry to free
+ */
+static void
+free_cache_entry (struct ResolveCache *rc)
{
- struct Record *pos;
- struct Record *next;
-
- next = entry->records_head;
- while (NULL != (pos = next))
- {
- next = pos->next;
- GNUNET_CONTAINER_DLL_remove (entry->records_head,
- entry->records_tail,
+ struct RecordListEntry *pos;
+
+ while (NULL != (pos = rc->records_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (rc->records_head,
+ rc->records_tail,
pos);
- if (NULL != pos->record)
- {
- GNUNET_DNSPARSER_free_record (pos->record);
- GNUNET_free (pos->record);
- }
+ GNUNET_DNSPARSER_free_record (pos->record);
+ GNUNET_free (pos->record);
+ GNUNET_free (pos);
+ }
+ GNUNET_free_non_null (rc->hostname);
+ GNUNET_CONTAINER_DLL_remove (cache_head,
+ cache_tail,
+ rc);
+ cache_size--;
+ GNUNET_free (rc);
+}
+
+
+/**
+ * Remove @a entry from cache.
+ *
+ * @param rc entry to free
+ */
+static void
+free_hosts_entry (struct ResolveCache *rc)
+{
+ struct RecordListEntry *pos;
+
+ while (NULL != (pos = rc->records_head))
+ {
+ GNUNET_CONTAINER_DLL_remove (rc->records_head,
+ rc->records_tail,
+ pos);
+ GNUNET_DNSPARSER_free_record (pos->record);
+ GNUNET_free (pos->record);
GNUNET_free (pos);
}
- if (NULL != entry->resolve_handle)
+ GNUNET_free_non_null (rc->hostname);
+ GNUNET_CONTAINER_DLL_remove (hosts_head,
+ hosts_tail,
+ rc);
+ cache_size--;
+ GNUNET_free (rc);
+}
+
+
+/**
+ * Release resources associated with @a al
+ *
+ * @param al an active lookup
+ */
+static void
+free_active_lookup (struct ActiveLookup *al)
+{
+ GNUNET_CONTAINER_DLL_remove (lookup_head,
+ lookup_tail,
+ al);
+ if (NULL != al->resolve_handle)
{
- GNUNET_DNSSTUB_resolve_cancel (entry->resolve_handle);
- entry->resolve_handle = NULL;
+ GNUNET_DNSSTUB_resolve_cancel (al->resolve_handle);
+ al->resolve_handle = NULL;
}
- if (NULL != entry->timeout_task)
+ if (NULL != al->timeout_task)
{
- GNUNET_SCHEDULER_cancel (entry->timeout_task);
- entry->timeout_task = NULL;
+ GNUNET_SCHEDULER_cancel (al->timeout_task);
+ al->timeout_task = NULL;
}
- GNUNET_free_non_null (entry->request_id);
- GNUNET_free (entry);
+ GNUNET_free_non_null (al->hostname);
+ GNUNET_free (al);
+}
+
+
+
+/**
+ * Find out if the configuration file line contains a string
+ * starting with "nameserver ", and if so, return a copy of
+ * the nameserver's IP.
+ *
+ * @param line line to parse
+ * @param line_len number of characters in @a line
+ * @return NULL if no nameserver is configured in this @a line
+ */
+static char *
+extract_dns_server (const char* line,
+ size_t line_len)
+{
+ if (0 == strncmp (line,
+ "nameserver ",
+ strlen ("nameserver ")))
+ return GNUNET_strndup (line + strlen ("nameserver "),
+ line_len - strlen ("nameserver "));
+ return NULL;
}
-static char*
-extract_dns_server (const char* line, size_t line_len)
+/**
+ * Find out if the configuration file line contains a string
+ * starting with "search ", and if so, return a copy of
+ * the machine's search domain.
+ *
+ * @param line line to parse
+ * @param line_len number of characters in @a line
+ * @return NULL if no nameserver is configured in this @a line
+ */
+static char *
+extract_search_domain (const char* line,
+ size_t line_len)
{
- if (0 == strncmp (line, "nameserver ", 11))
- return GNUNET_strndup (line + 11, line_len - 11);
+ if (0 == strncmp (line,
+ "search ",
+ strlen ("search ")))
+ return GNUNET_strndup (line + strlen ("search "),
+ line_len - strlen ("search "));
return NULL;
}
-
+
/**
- * reads the list of nameservers from /etc/resolve.conf
+ * Reads the list of nameservers from /etc/resolve.conf
*
* @param server_addrs[out] a list of null-terminated server address strings
* @return the number of server addresses in @server_addrs, -1 on error
*/
-static ssize_t
+static int
lookup_dns_servers (char ***server_addrs)
{
struct GNUNET_DISK_FileHandle *fh;
- char buf[2048];
- ssize_t bytes_read;
- size_t read_offset = 0;
- unsigned int num_dns_servers = 0;
-
+ struct GNUNET_DISK_MapHandle *mh;
+ off_t bytes_read;
+ const char *buf;
+ size_t read_offset;
+ unsigned int num_dns_servers;
+
fh = GNUNET_DISK_file_open ("/etc/resolv.conf",
GNUNET_DISK_OPEN_READ,
GNUNET_DISK_PERM_NONE);
"DNS resolution will not be possible.\n");
return -1;
}
- bytes_read = GNUNET_DISK_file_read (fh,
- buf,
- sizeof (buf));
+ if (GNUNET_OK !=
+ GNUNET_DISK_file_handle_size (fh,
+ &bytes_read))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not determine size of /etc/resolv.conf. "
+ "DNS resolution will not be possible.\n");
+ GNUNET_DISK_file_close (fh);
+ return -1;
+ }
+ if ((size_t) bytes_read > SIZE_MAX)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "/etc/resolv.conf file too large to mmap. "
+ "DNS resolution will not be possible.\n");
+ GNUNET_DISK_file_close (fh);
+ return -1;
+ }
+ buf = GNUNET_DISK_file_map (fh,
+ &mh,
+ GNUNET_DISK_MAP_TYPE_READ,
+ (size_t) bytes_read);
*server_addrs = NULL;
- while (read_offset < bytes_read)
+ read_offset = 0;
+ num_dns_servers = 0;
+ while (read_offset < (size_t) bytes_read)
{
- char *newline;
+ const char *newline;
size_t line_len;
char *dns_server;
-
- newline = strchr (buf + read_offset, '\n');
+
+ newline = strchr (buf + read_offset,
+ '\n');
if (NULL == newline)
- {
break;
- }
line_len = newline - buf - read_offset;
- dns_server = extract_dns_server (buf + read_offset, line_len);
+ dns_server = extract_dns_server (buf + read_offset,
+ line_len);
if (NULL != dns_server)
{
GNUNET_array_append (*server_addrs,
num_dns_servers,
dns_server);
}
+ else if (NULL == my_domain)
+ {
+ my_domain = extract_search_domain (buf + read_offset,
+ line_len);
+ }
read_offset += line_len + 1;
}
+ GNUNET_DISK_file_unmap (mh);
GNUNET_DISK_file_close (fh);
- return num_dns_servers;
+ return (int) num_dns_servers;
}
+/**
+ * Compute name to use for DNS reverse lookups from @a ip.
+ *
+ * @param ip IP address to resolve, in binary format, network byte order
+ * @param af address family of @a ip, AF_INET or AF_INET6
+ */
static char *
-make_reverse_hostname (const void *ip, int af)
+make_reverse_hostname (const void *ip,
+ int af)
{
- char *buf = GNUNET_new_array (80, char);
+ char *buf = GNUNET_new_array (80,
+ char);
int pos = 0;
+
if (AF_INET == af)
{
struct in_addr *addr = (struct in_addr *)ip;
uint32_t ip_int = addr->s_addr;
+
for (int i = 3; i >= 0; i--)
{
int n = GNUNET_snprintf (buf + pos,
}
pos += n;
}
- pos += GNUNET_snprintf (buf + pos, 80 - pos, "in-addr.arpa");
+ pos += GNUNET_snprintf (buf + pos,
+ 80 - pos,
+ "in-addr.arpa");
}
else if (AF_INET6 == af)
{
struct in6_addr *addr = (struct in6_addr *)ip;
for (int i = 15; i >= 0; i--)
{
- int n = GNUNET_snprintf (buf + pos, 80 - pos, "%x.", addr->s6_addr[i] & 0xf);
+ int n = GNUNET_snprintf (buf + pos,
+ 80 - pos,
+ "%x.",
+ addr->s6_addr[i] & 0xf);
if (n < 0)
{
GNUNET_free (buf);
return NULL;
}
pos += n;
- n = GNUNET_snprintf (buf + pos, 80 - pos, "%x.", addr->s6_addr[i] >> 4);
+ n = GNUNET_snprintf (buf + pos,
+ 80 - pos,
+ "%x.",
+ addr->s6_addr[i] >> 4);
if (n < 0)
{
GNUNET_free (buf);
}
pos += n;
}
- pos += GNUNET_snprintf (buf + pos, 80 - pos, "ip6.arpa");
+ pos += GNUNET_snprintf (buf + pos,
+ 80 - pos,
+ "ip6.arpa");
}
buf[pos] = '\0';
return buf;
}
-static void
+/**
+ * Send DNS @a record back to our @a client.
+ *
+ * @param record information to transmit
+ * @param record_type requested record type from client
+ * @param client_request_id to which request are we responding
+ * @param client where to send @a record
+ * @return #GNUNET_YES if we sent a reply,
+ * #GNUNET_NO if the record type is not understood or
+ * does not match @a record_type
+ */
+static int
send_reply (struct GNUNET_DNSPARSER_Record *record,
- uint16_t request_id,
+ uint16_t record_type,
+ uint32_t client_request_id,
struct GNUNET_SERVICE_Client *client)
{
struct GNUNET_RESOLVER_ResponseMessage *msg;
struct GNUNET_MQ_Envelope *env;
- void *payload;
+ const void *payload;
size_t payload_len;
switch (record->type)
{
- case GNUNET_DNSPARSER_TYPE_PTR:
- {
- char *hostname = record->data.hostname;
- payload = hostname;
- payload_len = strlen (hostname) + 1;
- break;
- }
- case GNUNET_DNSPARSER_TYPE_A:
- case GNUNET_DNSPARSER_TYPE_AAAA:
- {
- payload = record->data.raw.data;
- payload_len = record->data.raw.data_len;
- break;
- }
- default:
- {
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Cannot handle DNS response type: unimplemented\n");
- return;
- }
+ case GNUNET_DNSPARSER_TYPE_CNAME:
+ if (GNUNET_DNSPARSER_TYPE_CNAME != record_type)
+ return GNUNET_NO;
+ payload = record->data.hostname;
+ payload_len = strlen (record->data.hostname) + 1;
+ break;
+ case GNUNET_DNSPARSER_TYPE_PTR:
+ if (GNUNET_DNSPARSER_TYPE_PTR != record_type)
+ return GNUNET_NO;
+ payload = record->data.hostname;
+ payload_len = strlen (record->data.hostname) + 1;
+ break;
+ case GNUNET_DNSPARSER_TYPE_A:
+ if ( (GNUNET_DNSPARSER_TYPE_A != record_type) &&
+ (GNUNET_DNSPARSER_TYPE_ALL != record_type) )
+ return GNUNET_NO;
+ payload = record->data.raw.data;
+ payload_len = record->data.raw.data_len;
+ break;
+ case GNUNET_DNSPARSER_TYPE_AAAA:
+ if ( (GNUNET_DNSPARSER_TYPE_AAAA != record_type) &&
+ (GNUNET_DNSPARSER_TYPE_ALL != record_type) )
+ return GNUNET_NO;
+ payload = record->data.raw.data;
+ payload_len = record->data.raw.data_len;
+ break;
+ default:
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Cannot handle DNS response type %u: not supported here\n",
+ record->type);
+ return GNUNET_NO;
}
env = GNUNET_MQ_msg_extra (msg,
payload_len,
GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE);
- msg->id = request_id;
+ msg->client_id = client_request_id;
GNUNET_memcpy (&msg[1],
payload,
payload_len);
GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client),
env);
+ return GNUNET_YES;
}
+/**
+ * Send message to @a client that we transmitted all
+ * responses for @a client_request_id
+ *
+ * @param client_request_id to which request are we responding
+ * @param client where to send @a record
+ */
static void
-send_end_msg (uint16_t request_id,
+send_end_msg (uint32_t client_request_id,
struct GNUNET_SERVICE_Client *client)
{
struct GNUNET_RESOLVER_ResponseMessage *msg;
struct GNUNET_MQ_Envelope *env;
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Sending end message\n");
+ "Sending END message\n");
env = GNUNET_MQ_msg (msg,
GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE);
- msg->id = request_id;
+ msg->client_id = client_request_id;
GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client),
env);
}
-static void
-handle_resolve_result (void *cls,
- const struct GNUNET_TUN_DnsHeader *dns,
- size_t dns_len)
+/**
+ * Remove expired entries from @a rc
+ *
+ * @param rc entry in resolver cache
+ * @return #GNUNET_YES if @a rc was completely expired
+ * #GNUNET_NO if some entries are left
+ */
+static int
+remove_expired (struct ResolveCache *rc)
{
- struct ResolveCache *cache = cls;
- struct GNUNET_DNSPARSER_Packet *parsed;
- uint16_t request_id = *cache->request_id;
- struct GNUNET_SERVICE_Client *client = cache->client;
+ struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
+ struct RecordListEntry *n;
- parsed = GNUNET_DNSPARSER_parse ((const char *)dns,
- dns_len);
- if (NULL == parsed)
+ for (struct RecordListEntry *pos = rc->records_head;
+ NULL != pos;
+ pos = n)
{
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Failed to parse DNS reply (request ID %u\n",
- request_id);
- return;
+ n = pos->next;
+ if (now.abs_value_us > pos->record->expiration_time.abs_value_us)
+ {
+ GNUNET_CONTAINER_DLL_remove (rc->records_head,
+ rc->records_tail,
+ pos);
+ GNUNET_DNSPARSER_free_record (pos->record);
+ GNUNET_free (pos->record);
+ GNUNET_free (pos);
+ }
}
- if (request_id != ntohs (parsed->id))
+ if (NULL == rc->records_head)
{
- GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "Request ID in DNS reply does not match\n");
- return;
+ free_cache_entry (rc);
+ return GNUNET_YES;
+ }
+ return GNUNET_NO;
+}
+
+
+/**
+ * Process DNS request for @a hostname with request ID @a request_id
+ * from @a client demanding records of type @a record_type.
+ *
+ * @param hostname DNS name to resolve
+ * @param record_type desired record type
+ * @param client_request_id client's request ID
+ * @param client who should get the result?
+ */
+static void
+process_get (const char *hostname,
+ uint16_t record_type,
+ uint32_t client_request_id,
+ struct GNUNET_SERVICE_Client *client);
+
+
+/**
+ * Get an IP address as a string (works for both IPv4 and IPv6). Note
+ * that the resolution happens asynchronously and that the first call
+ * may not immediately result in the FQN (but instead in a
+ * human-readable IP address).
+ *
+ * @param hostname what hostname was to be resolved
+ * @param record_type what type of record was requested
+ * @param client_request_id unique identification of the client's request
+ * @param client handle to the client making the request (for sending the reply)
+ */
+static int
+try_cache (const char *hostname,
+ uint16_t record_type,
+ uint32_t client_request_id,
+ struct GNUNET_SERVICE_Client *client)
+{
+ struct ResolveCache *pos;
+ struct ResolveCache *next;
+ int found;
+ int in_hosts;
+
+ in_hosts = GNUNET_NO;
+ for (pos = hosts_head; NULL != pos; pos = pos->next)
+ if (0 == strcmp (pos->hostname,
+ hostname))
+ {
+ in_hosts = GNUNET_YES;
+ break;
+ }
+ if (NULL == pos)
+ {
+ next = cache_head;
+ for (pos = next; NULL != pos; pos = next)
+ {
+ next = pos->next;
+ if (GNUNET_YES == remove_expired (pos))
+ continue;
+ if (0 == strcmp (pos->hostname,
+ hostname))
+ break;
+ }
}
- else if (0 == parsed->num_answers)
+ if (NULL == pos)
{
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "DNS reply (request ID %u) contains no answers\n",
- request_id);
+ "No cache entry for '%s'\n",
+ hostname);
+ return GNUNET_NO;
+ }
+ if ( (GNUNET_NO == in_hosts) &&
+ (cache_head != pos) )
+ {
+ /* move result to head to achieve LRU for cache eviction */
GNUNET_CONTAINER_DLL_remove (cache_head,
- cache_tail,
- cache);
- free_cache_entry (cache);
- cache = NULL;
+ cache_tail,
+ pos);
+ GNUNET_CONTAINER_DLL_insert (cache_head,
+ cache_tail,
+ pos);
}
- else
+ found = GNUNET_NO;
+ for (struct RecordListEntry *rle = pos->records_head;
+ NULL != rle;
+ rle = rle->next)
{
+ const struct GNUNET_DNSPARSER_Record *record = rle->record;
+
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Got reply for request ID %u\n",
- request_id);
- for (unsigned int i = 0; i != parsed->num_answers; i++)
+ "Found cache entry for '%s', record type '%u'\n",
+ hostname,
+ record_type);
+ if ( (GNUNET_DNSPARSER_TYPE_CNAME == record->type) &&
+ (GNUNET_DNSPARSER_TYPE_CNAME != record_type) &&
+ (GNUNET_NO == found) )
{
- struct Record *cache_entry = GNUNET_new (struct Record);
- struct GNUNET_DNSPARSER_Record *record = &parsed->answers[i];
- cache_entry->record = GNUNET_DNSPARSER_duplicate_record (record);
- GNUNET_CONTAINER_DLL_insert (cache->records_head,
- cache->records_tail,
- cache_entry);
- send_reply (cache_entry->record,
- request_id,
- cache->client);
- }
- GNUNET_free_non_null (cache->request_id);
- cache->request_id = NULL;
- }
- send_end_msg (request_id,
- client);
- if (NULL != cache)
- cache->client = NULL;
- GNUNET_SCHEDULER_cancel (cache->timeout_task);
- GNUNET_DNSSTUB_resolve_cancel (cache->resolve_handle);
- cache->timeout_task = NULL;
- cache->resolve_handle = NULL;
- GNUNET_DNSPARSER_free_packet (parsed);
-}
-
-
-static void
-handle_resolve_timeout (void *cls)
-{
- struct ResolveCache *cache = cls;
+ const char *hostname = record->data.hostname;
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "timeout!\n");
- if (NULL != cache->resolve_handle)
- {
- GNUNET_DNSSTUB_resolve_cancel (cache->resolve_handle);
- cache->resolve_handle = NULL;
+ process_get (hostname,
+ record_type,
+ client_request_id,
+ client);
+ return GNUNET_YES; /* counts as a cache "hit" */
+ }
+ found |= send_reply (rle->record,
+ record_type,
+ client_request_id,
+ client);
}
- GNUNET_CONTAINER_DLL_remove (cache_head,
- cache_tail,
- cache);
- free_cache_entry (cache);
+ if (GNUNET_NO == found)
+ return GNUNET_NO; /* had records, but none matched! */
+ send_end_msg (client_request_id,
+ client);
+ return GNUNET_YES;
}
+/**
+ * Create DNS query for @a hostname of type @a type
+ * with DNS request ID @a dns_id.
+ *
+ * @param hostname DNS name to query
+ * @param type requested DNS record type
+ * @param dns_id what should be the DNS request ID
+ * @param packet_buf[out] where to write the request packet
+ * @param packet_size[out] set to size of @a packet_buf on success
+ * @return #GNUNET_OK on success
+ */
static int
-resolve_and_cache (const char* hostname,
- uint16_t record_type,
- uint16_t request_id,
- struct GNUNET_SERVICE_Client *client)
+pack (const char *hostname,
+ uint16_t type,
+ uint16_t dns_id,
+ char **packet_buf,
+ size_t *packet_size)
{
- char *packet_buf;
- size_t packet_size;
struct GNUNET_DNSPARSER_Query query;
struct GNUNET_DNSPARSER_Packet packet;
- struct ResolveCache *cache;
- struct GNUNET_TIME_Relative timeout =
- GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "resolve_and_cache\n");
query.name = (char *)hostname;
- query.type = record_type;
+ query.type = type;
query.dns_traffic_class = GNUNET_TUN_DNS_CLASS_INTERNET;
memset (&packet,
0,
sizeof (packet));
packet.num_queries = 1;
packet.queries = &query;
- packet.id = htons (request_id);
+ packet.id = htons (dns_id);
packet.flags.recursion_desired = 1;
- if (GNUNET_OK !=
+ if (GNUNET_OK !=
GNUNET_DNSPARSER_pack (&packet,
UINT16_MAX,
- &packet_buf,
- &packet_size))
+ packet_buf,
+ packet_size))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Failed to pack query for hostname `%s'\n",
hostname);
+ packet_buf = NULL;
return GNUNET_SYSERR;
-
- }
- cache = GNUNET_malloc (sizeof (struct ResolveCache));
- cache->record_type = record_type;
- cache->request_id = GNUNET_memdup (&request_id, sizeof (request_id));
- cache->client = client;
- cache->timeout_task = GNUNET_SCHEDULER_add_delayed (timeout,
- &handle_resolve_timeout,
- cache);
- cache->resolve_handle =
- GNUNET_DNSSTUB_resolve (dnsstub_ctx,
- packet_buf,
- packet_size,
- &handle_resolve_result,
- cache);
- GNUNET_CONTAINER_DLL_insert (cache_head,
- cache_tail,
- cache);
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "resolve %s, request_id = %u\n",
- hostname,
- request_id);
- GNUNET_free (packet_buf);
+ }
return GNUNET_OK;
}
-
-static const char *
-get_hostname (struct ResolveCache *cache_entry)
+static void
+cache_answers(const char* name,
+ struct GNUNET_DNSPARSER_Record *records,
+ unsigned int num_records)
{
- if (NULL != cache_entry->records_head)
+ struct ResolveCache *rc;
+ struct GNUNET_DNSPARSER_Record *record;
+ struct RecordListEntry *rle;
+
+ for (unsigned int i = 0; i != num_records; i++)
{
- GNUNET_assert (NULL != cache_entry->records_head);
- GNUNET_assert (NULL != cache_entry->records_head->record);
- GNUNET_assert (NULL != cache_entry->records_head->record->name);
- return cache_entry->records_head->record->name;
+ record = &records[i];
+
+ for (rc = cache_head; NULL != rc; rc = rc->next)
+ if (0 == strcasecmp (rc->hostname,
+ name))
+ break;
+ if (NULL == rc)
+ {
+ rc = GNUNET_new (struct ResolveCache);
+ rc->hostname = GNUNET_strdup (name);
+ GNUNET_CONTAINER_DLL_insert (cache_head,
+ cache_tail,
+ rc);
+ cache_size++;
+ }
+ /* TODO: ought to check first if we have this exact record
+ already in the cache! */
+ rle = GNUNET_new (struct RecordListEntry);
+ rle->record = GNUNET_DNSPARSER_duplicate_record (record);
+ GNUNET_CONTAINER_DLL_insert (rc->records_head,
+ rc->records_tail,
+ rle);
}
- return NULL;
}
-
-static const uint16_t *
-get_record_type (struct ResolveCache *cache_entry)
+/**
+ * We got a result from DNS. Add it to the cache and
+ * see if we can make our client happy...
+ *
+ * @param cls the `struct ActiveLookup`
+ * @param dns the DNS response
+ * @param dns_len number of bytes in @a dns
+ */
+static void
+handle_resolve_result (void *cls,
+ const struct GNUNET_TUN_DnsHeader *dns,
+ size_t dns_len)
{
- if (NULL != cache_entry->records_head)
- return &cache_entry->record_type;
- return NULL;
+ struct ActiveLookup *al = cls;
+ struct GNUNET_DNSPARSER_Packet *parsed;
+
+ parsed = GNUNET_DNSPARSER_parse ((const char *)dns,
+ dns_len);
+ if (NULL == parsed)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Failed to parse DNS reply (hostname %s, request ID %u)\n",
+ al->hostname,
+ al->dns_id);
+ return;
+ }
+ if (al->dns_id != ntohs (parsed->id))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Request ID in DNS reply does not match\n");
+ GNUNET_DNSPARSER_free_packet (parsed);
+ return;
+ }
+ if (0 == parsed->num_answers + parsed->num_authority_records + parsed->num_additional_records)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "DNS reply (hostname %s, request ID %u) contains no answers\n",
+ al->hostname,
+ (unsigned int) al->client_request_id);
+ /* resume by trying again from cache */
+ if (GNUNET_NO ==
+ try_cache (al->hostname,
+ al->record_type,
+ al->client_request_id,
+ al->client))
+ /* cache failed, tell client we could not get an answer */
+ {
+ send_end_msg (al->client_request_id,
+ al->client);
+ }
+ GNUNET_DNSPARSER_free_packet (parsed);
+ free_active_lookup (al);
+ return;
+ }
+ /* LRU-based cache eviction: we remove from tail */
+ while (cache_size > MAX_CACHE)
+ free_cache_entry (cache_tail);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Got reply for hostname %s and request ID %u\n",
+ al->hostname,
+ (unsigned int) al->client_request_id);
+ /* add to cache */
+ cache_answers(al->hostname,
+ parsed->answers, parsed->num_answers);
+ cache_answers(al->hostname,
+ parsed->authority_records, parsed->num_authority_records);
+ cache_answers(al->hostname,
+ parsed->additional_records, parsed->num_additional_records);
+
+ /* see if we need to do the 2nd request for AAAA records */
+ if ( (GNUNET_DNSPARSER_TYPE_ALL == al->record_type) &&
+ (GNUNET_NO == al->did_aaaa) )
+ {
+ char *packet_buf;
+ size_t packet_size;
+ uint16_t dns_id;
+
+ dns_id = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
+ UINT16_MAX);
+ if (GNUNET_OK ==
+ pack (al->hostname,
+ GNUNET_DNSPARSER_TYPE_AAAA,
+ dns_id,
+ &packet_buf,
+ &packet_size))
+ {
+ al->did_aaaa = GNUNET_YES;
+ al->dns_id = dns_id;
+ GNUNET_DNSSTUB_resolve_cancel (al->resolve_handle);
+ al->resolve_handle =
+ GNUNET_DNSSTUB_resolve (dnsstub_ctx,
+ packet_buf,
+ packet_size,
+ &handle_resolve_result,
+ al);
+ GNUNET_free (packet_buf);
+ GNUNET_DNSPARSER_free_packet (parsed);
+ return;
+ }
+ }
+
+ /* resume by trying again from cache */
+ if (GNUNET_NO ==
+ try_cache (al->hostname,
+ al->record_type,
+ al->client_request_id,
+ al->client))
+ /* cache failed, tell client we could not get an answer */
+ {
+ send_end_msg (al->client_request_id,
+ al->client);
+ }
+ free_active_lookup (al);
+ GNUNET_DNSPARSER_free_packet (parsed);
}
-static const struct GNUNET_TIME_Absolute *
-get_expiration_time (struct ResolveCache *cache_entry)
+/**
+ * We encountered a timeout trying to perform a
+ * DNS lookup.
+ *
+ * @param cls a `struct ActiveLookup`
+ */
+static void
+handle_resolve_timeout (void *cls)
{
- if (NULL != cache_entry->records_head)
- return &cache_entry->records_head->record->expiration_time;
- return NULL;
+ struct ActiveLookup *al = cls;
+
+ al->timeout_task = NULL;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "DNS lookup timeout!\n");
+ send_end_msg (al->client_request_id,
+ al->client);
+ free_active_lookup (al);
}
+/**
+ * Initiate an active lookup, then cache the result and
+ * try to then complete the resolution.
+ *
+ * @param hostname DNS name to resolve
+ * @param record_type record type to locate
+ * @param client_request_id client request ID
+ * @param client handle to the client
+ * @return #GNUNET_OK if the DNS query is now pending
+ */
static int
-remove_if_expired (struct ResolveCache *cache_entry)
+resolve_and_cache (const char* hostname,
+ uint16_t record_type,
+ uint32_t client_request_id,
+ struct GNUNET_SERVICE_Client *client)
{
- struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
+ char *packet_buf;
+ size_t packet_size;
+ struct ActiveLookup *al;
+ uint16_t dns_id;
+ uint16_t type;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "resolve_and_cache `%s'\n",
+ hostname);
+ dns_id = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_NONCE,
+ UINT16_MAX);
- if ( (NULL != cache_entry->records_head) &&
- (now.abs_value_us > get_expiration_time (cache_entry)->abs_value_us) )
+ if (GNUNET_DNSPARSER_TYPE_ALL == record_type)
+ type = GNUNET_DNSPARSER_TYPE_A;
+ else
+ type = record_type;
+ if (GNUNET_OK !=
+ pack (hostname,
+ type,
+ dns_id,
+ &packet_buf,
+ &packet_size))
{
- GNUNET_CONTAINER_DLL_remove (cache_head,
- cache_tail,
- cache_entry);
- free_cache_entry (cache_entry);
- return GNUNET_YES;
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Failed to pack query for hostname `%s'\n",
+ hostname);
+ return GNUNET_SYSERR;
}
- return GNUNET_NO;
+
+ al = GNUNET_new (struct ActiveLookup);
+ al->hostname = GNUNET_strdup (hostname);
+ al->record_type = record_type;
+ al->client_request_id = client_request_id;
+ al->dns_id = dns_id;
+ al->client = client;
+ al->timeout_task = GNUNET_SCHEDULER_add_delayed (DNS_TIMEOUT,
+ &handle_resolve_timeout,
+ al);
+ al->resolve_handle =
+ GNUNET_DNSSTUB_resolve (dnsstub_ctx,
+ packet_buf,
+ packet_size,
+ &handle_resolve_result,
+ al);
+ GNUNET_free (packet_buf);
+ GNUNET_CONTAINER_DLL_insert (lookup_head,
+ lookup_tail,
+ al);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Resolving %s, client_request_id = %u, dns_id = %u\n",
+ hostname,
+ (unsigned int) client_request_id,
+ (unsigned int) dns_id);
+ return GNUNET_OK;
}
/**
- * Get an IP address as a string (works for both IPv4 and IPv6). Note
- * that the resolution happens asynchronously and that the first call
- * may not immediately result in the FQN (but instead in a
- * human-readable IP address).
+ * Process DNS request for @a hostname with request ID @a client_request_id
+ * from @a client demanding records of type @a record_type.
*
- * @param client handle to the client making the request (for sending the reply)
- * @param af AF_INET or AF_INET6
- * @param ip `struct in_addr` or `struct in6_addr`
+ * @param hostname DNS name to resolve
+ * @param record_type desired record type
+ * @param client_request_id client's request ID
+ * @param client who should get the result?
*/
-static int
-try_cache (const char *hostname,
- uint16_t record_type,
- uint16_t request_id,
- struct GNUNET_SERVICE_Client *client)
+static void
+process_get (const char *hostname,
+ uint16_t record_type,
+ uint32_t client_request_id,
+ struct GNUNET_SERVICE_Client *client)
{
- struct ResolveCache *pos;
- struct ResolveCache *next;
+ char fqdn[255];
- next = cache_head;
- while ( (NULL != (pos = next)) &&
- ( (NULL == pos->records_head) ||
- (0 != strcmp (get_hostname (pos), hostname)) ||
- (*get_record_type (pos) != record_type) ) )
+ if (GNUNET_NO !=
+ try_cache (hostname,
+ record_type,
+ client_request_id,
+ client))
+ return;
+ if ( (NULL != my_domain) &&
+ (NULL == strchr (hostname,
+ (unsigned char) '.')) &&
+ (strlen (hostname) + strlen (my_domain) <= 253) )
+ {
+ GNUNET_snprintf (fqdn,
+ sizeof (fqdn),
+ "%s.%s",
+ hostname,
+ my_domain);
+ }
+ else if (strlen (hostname) < 255)
{
- next = pos->next;
- remove_if_expired (pos);
+ GNUNET_snprintf (fqdn,
+ sizeof (fqdn),
+ "%s",
+ hostname);
+ }
+ else
+ {
+ GNUNET_break (0);
+ GNUNET_SERVICE_client_drop (client);
+ return;
}
- if (NULL != pos)
+ if (GNUNET_NO ==
+ try_cache (fqdn,
+ record_type,
+ client_request_id,
+ client))
{
- if (GNUNET_NO == remove_if_expired (pos))
+ if (GNUNET_OK !=
+ resolve_and_cache (fqdn,
+ record_type,
+ client_request_id,
+ client))
{
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "found cache entry for '%s', record type '%u'\n",
- hostname,
- record_type);
- struct Record *cache_pos = pos->records_head;
- while (NULL != cache_pos)
- {
- send_reply (cache_pos->record,
- request_id,
- client);
- cache_pos = cache_pos->next;
- }
- send_end_msg (request_id,
- client);
- return GNUNET_YES;
+ send_end_msg (client_request_id,
+ client);
}
}
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "no cache entry for '%s'\n",
- hostname);
- return GNUNET_NO;
}
*/
static int
check_get (void *cls,
- const struct GNUNET_RESOLVER_GetMessage *get)
+ const struct GNUNET_RESOLVER_GetMessage *get)
{
uint16_t size;
int direction;
direction = ntohl (get->direction);
if (GNUNET_NO == direction)
{
- /* IP from hostname */
- const char *hostname;
-
- hostname = (const char *) &get[1];
- if (hostname[size - 1] != '\0')
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
+ GNUNET_MQ_check_zero_termination (get);
return GNUNET_OK;
}
af = ntohl (get->af);
switch (af)
{
- case AF_INET:
- if (size != sizeof (struct in_addr))
- {
- GNUNET_break (0);
- return GNUNET_SYSERR;
- }
- break;
- case AF_INET6:
- if (size != sizeof (struct in6_addr))
- {
+ case AF_INET:
+ if (size != sizeof (struct in_addr))
+ {
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ break;
+ case AF_INET6:
+ if (size != sizeof (struct in6_addr))
+ {
+ GNUNET_break (0);
+ return GNUNET_SYSERR;
+ }
+ break;
+ default:
GNUNET_break (0);
return GNUNET_SYSERR;
- }
- break;
- default:
- GNUNET_break (0);
- return GNUNET_SYSERR;
}
return GNUNET_OK;
}
-static void
-process_get (const char *hostname,
- uint16_t record_type,
- uint16_t request_id,
- struct GNUNET_SERVICE_Client *client)
-{
- if (GNUNET_NO == try_cache (hostname, record_type, request_id, client))
- {
- int result = resolve_and_cache (hostname,
- record_type,
- request_id,
- client);
- GNUNET_assert (GNUNET_OK == result);
- }
-}
-
-
/**
* Handle GET-message.
*
*/
static void
handle_get (void *cls,
- const struct GNUNET_RESOLVER_GetMessage *msg)
+ const struct GNUNET_RESOLVER_GetMessage *msg)
{
struct GNUNET_SERVICE_Client *client = cls;
int direction;
int af;
- uint16_t request_id;
- const char *hostname;
+ uint32_t client_request_id;
+ char *hostname;
direction = ntohl (msg->direction);
af = ntohl (msg->af);
- request_id = ntohs (msg->id);
+ client_request_id = msg->client_id;
+ GNUNET_SERVICE_client_continue (client);
if (GNUNET_NO == direction)
{
/* IP from hostname */
hostname = GNUNET_strdup ((const char *) &msg[1]);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Client asks to resolve `%s'\n",
+ hostname);
switch (af)
{
case AF_UNSPEC:
- {
- process_get (hostname, GNUNET_DNSPARSER_TYPE_ALL, request_id, client);
- break;
- }
+ {
+ process_get (hostname,
+ GNUNET_DNSPARSER_TYPE_ALL,
+ client_request_id,
+ client);
+ break;
+ }
case AF_INET:
- {
- process_get (hostname, GNUNET_DNSPARSER_TYPE_A, request_id, client);
- break;
- }
+ {
+ process_get (hostname,
+ GNUNET_DNSPARSER_TYPE_A,
+ client_request_id,
+ client);
+ break;
+ }
case AF_INET6:
- {
- process_get (hostname, GNUNET_DNSPARSER_TYPE_AAAA, request_id, client);
- break;
- }
+ {
+ process_get (hostname,
+ GNUNET_DNSPARSER_TYPE_AAAA,
+ client_request_id,
+ client);
+ break;
+ }
default:
- {
- GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "got invalid af: %d\n",
- af);
- GNUNET_assert (0);
- }
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "got invalid af: %d\n",
+ af);
+ GNUNET_assert (0);
+ }
}
}
else
{
/* hostname from IP */
- hostname = make_reverse_hostname (&msg[1], af);
- process_get (hostname, GNUNET_DNSPARSER_TYPE_PTR, request_id, client);
+ hostname = make_reverse_hostname (&msg[1],
+ af);
+ process_get (hostname,
+ GNUNET_DNSPARSER_TYPE_PTR,
+ client_request_id,
+ client);
}
- GNUNET_free_non_null ((char *)hostname);
- GNUNET_SERVICE_client_continue (client);
+ GNUNET_free_non_null (hostname);
}
-static void
+/**
+ * Service is shutting down, clean up.
+ *
+ * @param cls NULL, unused
+ */
+static void
shutdown_task (void *cls)
{
(void) cls;
- struct ResolveCache *pos;
- while (NULL != (pos = cache_head))
+ while (NULL != lookup_head)
+ free_active_lookup (lookup_head);
+ while (NULL != cache_head)
+ free_cache_entry (cache_head);
+ while (NULL != hosts_head)
+ free_hosts_entry (hosts_head);
+ GNUNET_DNSSTUB_stop (dnsstub_ctx);
+ GNUNET_free_non_null (my_domain);
+}
+
+
+/**
+ * Add information about a host from /etc/hosts
+ * to our cache.
+ *
+ * @param hostname the name of the host
+ * @param rec_type DNS record type to use
+ * @param data payload
+ * @param data_size number of bytes in @a data
+ */
+static void
+add_host (const char *hostname,
+ uint16_t rec_type,
+ const void *data,
+ size_t data_size)
+{
+ struct ResolveCache *rc;
+ struct RecordListEntry *rle;
+ struct GNUNET_DNSPARSER_Record *rec;
+
+ rec = GNUNET_malloc (sizeof (struct GNUNET_DNSPARSER_Record));
+ rec->expiration_time = GNUNET_TIME_UNIT_FOREVER_ABS;
+ rec->type = rec_type;
+ rec->dns_traffic_class = GNUNET_TUN_DNS_CLASS_INTERNET;
+ rec->name = GNUNET_strdup (hostname);
+ rec->data.raw.data = GNUNET_memdup (data,
+ data_size);
+ rec->data.raw.data_len = data_size;
+ rle = GNUNET_new (struct RecordListEntry);
+ rle->record = rec;
+ rc = GNUNET_new (struct ResolveCache);
+ rc->hostname = GNUNET_strdup (hostname);
+ GNUNET_CONTAINER_DLL_insert (rc->records_head,
+ rc->records_tail,
+ rle);
+ GNUNET_CONTAINER_DLL_insert (hosts_head,
+ hosts_tail,
+ rc);
+}
+
+
+/**
+ * Extract host information from a line in /etc/hosts
+ *
+ * @param line the line to parse
+ * @param line_len number of bytes in @a line
+ */
+static void
+extract_hosts (const char *line,
+ size_t line_len)
+{
+ const char *c;
+ struct in_addr v4;
+ struct in6_addr v6;
+ char *tbuf;
+ char *tok;
+
+ /* ignore everything after '#' */
+ c = memrchr (line,
+ (unsigned char) '#',
+ line_len);
+ if (NULL != c)
+ line_len = c - line;
+ /* ignore leading whitespace */
+ while ( (0 < line_len) &&
+ isspace ((unsigned char) *line) )
{
- GNUNET_CONTAINER_DLL_remove (cache_head,
- cache_tail,
- pos);
- free_cache_entry (pos);
+ line++;
+ line_len--;
}
- GNUNET_DNSSTUB_stop (dnsstub_ctx);
+ tbuf = GNUNET_strndup (line,
+ line_len);
+ tok = strtok (tbuf, " \t");
+ if (NULL == tok)
+ {
+ GNUNET_free (tbuf);
+ return;
+ }
+ if (1 == inet_pton (AF_INET,
+ tok,
+ &v4))
+ {
+ while (NULL != (tok = strtok (NULL, " \t")))
+ add_host (tok,
+ GNUNET_DNSPARSER_TYPE_A,
+ &v4,
+ sizeof (struct in_addr));
+ }
+ else if (1 == inet_pton (AF_INET6,
+ tok,
+ &v6))
+ {
+ while (NULL != (tok = strtok (NULL, " \t")))
+ add_host (tok,
+ GNUNET_DNSPARSER_TYPE_AAAA,
+ &v6,
+ sizeof (struct in6_addr));
+ }
+ GNUNET_free (tbuf);
+}
+
+
+/**
+ * Reads the list of hosts from /etc/hosts.
+ */
+static void
+load_etc_hosts (void)
+{
+ struct GNUNET_DISK_FileHandle *fh;
+ struct GNUNET_DISK_MapHandle *mh;
+ off_t bytes_read;
+ const char *buf;
+ size_t read_offset;
+
+ fh = GNUNET_DISK_file_open ("/etc/hosts",
+ GNUNET_DISK_OPEN_READ,
+ GNUNET_DISK_PERM_NONE);
+ if (NULL == fh)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ "Failed to open /etc/hosts");
+ return;
+ }
+ if (GNUNET_OK !=
+ GNUNET_DISK_file_handle_size (fh,
+ &bytes_read))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not determin size of /etc/hosts. "
+ "DNS resolution will not be possible.\n");
+ GNUNET_DISK_file_close (fh);
+ return;
+ }
+ if ((size_t) bytes_read > SIZE_MAX)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "/etc/hosts file too large to mmap. "
+ "DNS resolution will not be possible.\n");
+ GNUNET_DISK_file_close (fh);
+ return;
+ }
+ buf = GNUNET_DISK_file_map (fh,
+ &mh,
+ GNUNET_DISK_MAP_TYPE_READ,
+ (size_t) bytes_read);
+ read_offset = 0;
+ while (read_offset < (size_t) bytes_read)
+ {
+ const char *newline;
+ size_t line_len;
+
+ newline = strchr (buf + read_offset,
+ '\n');
+ if (NULL == newline)
+ break;
+ line_len = newline - buf - read_offset;
+ extract_hosts (buf + read_offset,
+ line_len);
+ read_offset += line_len + 1;
+ }
+ GNUNET_DISK_file_unmap (mh);
+ GNUNET_DISK_file_close (fh);
}
+/**
+ * Service is starting, initialize everything.
+ *
+ * @param cls NULL, unused
+ * @param cfg our configuration
+ * @param sh service handle
+ */
static void
init_cb (void *cls,
- const struct GNUNET_CONFIGURATION_Handle *cfg,
- struct GNUNET_SERVICE_Handle *sh)
+ const struct GNUNET_CONFIGURATION_Handle *cfg,
+ struct GNUNET_SERVICE_Handle *sh)
{
+ char **dns_servers;
+ int num_dns_servers;
+
(void) cfg;
(void) sh;
-
+ load_etc_hosts ();
GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
- cls);
+ cls);
dnsstub_ctx = GNUNET_DNSSTUB_start (128);
- char **dns_servers;
- ssize_t num_dns_servers = lookup_dns_servers (&dns_servers);
- if (0 == num_dns_servers)
+ dns_servers = NULL;
+ num_dns_servers = lookup_dns_servers (&dns_servers);
+ if (0 >= num_dns_servers)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
- "no DNS server available. DNS resolution will not be possible.\n");
+ _("No DNS server available. DNS resolution will not be possible.\n"));
+ return;
}
- for (int i = 0; i != num_dns_servers; i++)
+ for (int i = 0; i < num_dns_servers; i++)
{
int result = GNUNET_DNSSTUB_add_dns_ip (dnsstub_ctx, dns_servers[i]);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "Adding DNS server '%s': %s\n",
- dns_servers[i],
- GNUNET_OK == result ? "success" : "failure");
+ "Adding DNS server '%s': %s\n",
+ dns_servers[i],
+ GNUNET_OK == result ? "success" : "failure");
GNUNET_free (dns_servers[i]);
}
GNUNET_free_non_null (dns_servers);
*/
static void *
connect_cb (void *cls,
- struct GNUNET_SERVICE_Client *c,
- struct GNUNET_MQ_Handle *mq)
+ struct GNUNET_SERVICE_Client *c,
+ struct GNUNET_MQ_Handle *mq)
{
(void) cls;
(void) mq;
*/
static void
disconnect_cb (void *cls,
- struct GNUNET_SERVICE_Client *c,
- void *internal_cls)
+ struct GNUNET_SERVICE_Client *c,
+ void *internal_cls)
{
+ struct ActiveLookup *n;
(void) cls;
- struct ResolveCache *pos = cache_head;
- while (NULL != pos)
+ GNUNET_assert (c == internal_cls);
+ n = lookup_head;
+ for (struct ActiveLookup *al = n;
+ NULL != al;
+ al = n)
{
- if (pos->client == c)
- {
- pos->client = NULL;
- }
- pos = pos->next;
+ n = al->next;
+ if (al->client == c)
+ free_active_lookup (al);
}
- GNUNET_assert (c == internal_cls);
}
&disconnect_cb,
NULL,
GNUNET_MQ_hd_var_size (get,
- GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST,
- struct GNUNET_RESOLVER_GetMessage,
- NULL),
+ GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST,
+ struct GNUNET_RESOLVER_GetMessage,
+ NULL),
GNUNET_MQ_handler_end ());