FD.io VPP  v20.09-64-g4f7b92f0a
Vector Packet Processing
dns.h
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1 /*
2  * Copyright (c) 2017 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #ifndef included_dns_h
17 #define included_dns_h
18 
19 #include <vppinfra/time.h>
20 #include <vppinfra/cache.h>
21 #include <vppinfra/error.h>
22 
23 #include <vppinfra/hash.h>
24 #include <dns/dns_packet.h>
25 #include <vnet/ip/ip.h>
26 #include <vppinfra/lock.h>
27 #include <vlibapi/api_common.h>
28 
29 typedef struct
30 {
38  u8 dst_address[16];
39  u8 *name;
41 
42 typedef enum
43 {
49 
50 typedef struct
51 {
52  /** flags */
53  volatile u8 flags;
54 
55  /** The name in "normal human being" notation, e.g. www.foobar.com */
56  u8 *name;
57 
58  /** For CNAME records, the "next name" to resolve */
60 
61  /** Expiration time */
63 
64  /** Cached dns request, for sending retries */
66 
67  /** Retry parameters */
70  int server_af;
73 
74  /** Cached dns response */
76 
77  /** Clients / peers awaiting responses */
80 
81 #define DNS_CACHE_ENTRY_FLAG_VALID (1<<0) /**< we have Actual Data */
82 #define DNS_CACHE_ENTRY_FLAG_STATIC (1<<1) /**< static entry */
83 #define DNS_CACHE_ENTRY_FLAG_CNAME (1<<2) /**< CNAME (indirect) entry */
84 
85 #define DNS_RETRIES_PER_SERVER 3
86 
87 #define DNS_RESOLVER_EVENT_RESOLVED 1
88 #define DNS_RESOLVER_EVENT_PENDING 2
89 
90 
91 typedef struct
92 {
93  /** Pool of cache entries */
95 
96  /** Pool indices of unresolved entries */
98 
99  /** Find cached record by name */
103 
104  /** enable / disable flag */
106 
107  /** udp port registration complete */
109 
110  /** upstream name servers, e.g. 8.8.8.8 */
112  ip6_address_t *ip6_name_servers;
113 
114  /** resolver process node index */
116 
117  /** config parameters */
121 
122  /** message-ID base */
124 
125  /* convenience */
128 } dns_main_t;
129 
130 extern dns_main_t dns_main;
131 
135 
136 #define foreach_dns46_request_error \
137 _(NONE, "No error") \
138 _(UNIMPLEMENTED, "Unimplemented") \
139 _(PROCESSED, "DNS request pkts processed") \
140 _(IP_OPTIONS, "DNS pkts with ip options (dropped)") \
141 _(BAD_REQUEST, "DNS pkts with serious discrepancies (dropped)") \
142 _(TOO_MANY_REQUESTS, "DNS pkts asking too many questions") \
143 _(RESOLUTION_REQUIRED, "DNS pkts pending upstream name resolution")
144 
145 typedef enum
146 {
147 #define _(sym,str) DNS46_REQUEST_ERROR_##sym,
149 #undef _
152 
153 #define foreach_dns46_reply_error \
154 _(DISABLED, "DNS pkts punted (feature disabled)") \
155 _(PROCESSED, "DNS reply pkts processed") \
156 _(NO_ELT, "No DNS pool element") \
157 _(FORMAT_ERROR, "DNS format errors") \
158 _(TEST_DROP, "DNS reply pkt dropped for test purposes") \
159 _(MULTIPLE_REPLY, "DNS multiple reply packets") \
160 _(NO_UNRESOLVED_ENTRY, "No unresolved entry for pkt")
161 
162 typedef enum
163 {
164 #define _(sym,str) DNS46_REPLY_ERROR_##sym,
166 #undef _
169 
171  dns_cache_entry_t * ep);
173  u32 ep_index, u8 * reply);
174 
176 
177 int
180 
181 void
183  dns_cache_entry_t * ep, ip6_address_t * server);
184 void
186  dns_cache_entry_t * ep, ip4_address_t * server);
187 
190  vlib_buffer_t * b0);
191 
194  vlib_buffer_t * b0);
195 
196 u8 *vnet_dns_labels_to_name (u8 * label, u8 * full_text,
197  u8 ** parse_from_here);
198 
200 
202 
203 static inline void
204 dns_cache_lock (dns_main_t * dm, int tag)
205 {
206  if (dm->cache_lock)
207  {
208  ASSERT (tag);
209  ASSERT (dm->cache_lock_tag == 0);
211  dm->cache_lock_tag = tag;
212  }
213 }
214 
215 static inline void
217 {
218  if (dm->cache_lock)
219  {
220  ASSERT (dm->cache_lock_tag);
221  dm->cache_lock_tag = 0;
223  }
224 }
225 
226 #endif /* included_dns_h */
227 
228 /*
229  * fd.io coding-style-patch-verification: ON
230  *
231  * Local Variables:
232  * eval: (c-set-style "gnu")
233  * End:
234  */
void vnet_send_dns6_reply(vlib_main_t *vm, dns_main_t *dm, dns_pending_request_t *t, dns_cache_entry_t *ep, vlib_buffer_t *b0)
Definition: dns.c:2721
Definition: dns.h:50
static_always_inline void clib_spinlock_unlock(clib_spinlock_t *p)
Definition: lock.h:119
static_always_inline void clib_spinlock_lock(clib_spinlock_t *p)
Definition: lock.h:80
ip6_address_t * ip6_name_servers
Definition: dns.h:112
dns_main_t dns_main
Definition: dns.c:42
u8 * vnet_dns_labels_to_name(u8 *label, u8 *full_text, u8 **parse_from_here)
arc-function for the above.
Definition: dns.c:495
vlib_node_registration_t dns46_reply_node
(constructor) VLIB_REGISTER_NODE (dns46_reply_node)
Definition: reply_node.c:42
vlib_node_registration_t dns4_request_node
(constructor) VLIB_REGISTER_NODE (dns4_request_node)
Definition: request_node.c:293
u8 * dns_response
Cached dns response.
Definition: dns.h:75
void vnet_send_dns_request(vlib_main_t *vm, dns_main_t *dm, dns_cache_entry_t *ep)
Definition: dns.c:537
int vnet_dns_cname_indirection_nolock(vlib_main_t *vm, dns_main_t *dm, u32 ep_index, u8 *reply)
Handle cname indirection.
Definition: dns.c:966
int retry_count
Retry parameters.
Definition: dns.h:68
vlib_main_t * vm
Definition: in2out_ed.c:1582
u32 client_context
Definition: dns.h:33
int vnet_dns_resolve_name(vlib_main_t *vm, dns_main_t *dm, u8 *name, dns_pending_request_t *t, dns_cache_entry_t **retp)
Definition: dns.c:810
unsigned char u8
Definition: types.h:56
double f64
Definition: types.h:142
void vnet_dns_create_resolver_process(vlib_main_t *vm, dns_main_t *dm)
u8 *() format_function_t(u8 *s, va_list *args)
Definition: format.h:48
clib_spinlock_t cache_lock
Definition: dns.h:101
u8 * dns_request
Cached dns request, for sending retries.
Definition: dns.h:65
f64 retry_timer
Definition: dns.h:72
u32 * unresolved_entries
Pool indices of unresolved entries.
Definition: dns.h:97
unsigned int u32
Definition: types.h:88
u32 resolver_process_node_index
resolver process node index
Definition: dns.h:115
dns_pending_request_t * pending_requests
Clients / peers awaiting responses.
Definition: dns.h:78
ip4_address_t * ip4_name_servers
upstream name servers, e.g.
Definition: dns.h:111
u8 * cname
For CNAME records, the "next name" to resolve.
Definition: dns.h:59
u8 * name
The name in "normal human being" notation, e.g.
Definition: dns.h:56
int cache_lock_tag
Definition: dns.h:102
unsigned short u16
Definition: types.h:57
#define foreach_dns46_reply_error
Definition: dns.h:153
void vnet_dns_send_dns6_request(vlib_main_t *vm, dns_main_t *dm, dns_cache_entry_t *ep, ip6_address_t *server)
Definition: dns.c:339
void vnet_send_dns4_reply(vlib_main_t *vm, dns_main_t *dm, dns_pending_request_t *t, dns_cache_entry_t *ep, vlib_buffer_t *b0)
Definition: dns.c:2730
u32 label
Definition: fib_types.api:25
dns46_reply_error_t
Definition: dns.h:162
int server_rotor
Definition: dns.h:69
API main structure, used by both vpp and binary API clients.
Definition: api_common.h:227
dns_pending_request_type_t
Definition: dns.h:42
api_main_t * api_main
Definition: dns.h:127
static void dns_cache_unlock(dns_main_t *dm)
Definition: dns.h:216
int vnet_dns_delete_entry_by_index_nolock(dns_main_t *dm, u32 index)
Definition: dns.c:662
u16 msg_id_base
message-ID base
Definition: dns.h:123
string name[64]
Definition: ip.api:44
#define ASSERT(truth)
volatile u8 flags
flags
Definition: dns.h:53
vnet_main_t * vnet_main
Definition: dns.h:126
int udp_ports_registered
udp port registration complete
Definition: dns.h:108
uword * cache_entry_by_name
Find cached record by name.
Definition: dns.h:100
vlib_node_registration_t dns6_request_node
(constructor) VLIB_REGISTER_NODE (dns6_request_node)
Definition: request_node.c:320
struct _vlib_node_registration vlib_node_registration_t
static void dns_cache_lock(dns_main_t *dm, int tag)
Definition: dns.h:204
u32 max_ttl_in_seconds
Definition: dns.h:119
u32 name_cache_size
config parameters
Definition: dns.h:118
VLIB buffer representation.
Definition: buffer.h:102
u64 uword
Definition: types.h:112
u32 index
Definition: flow_types.api:221
format_function_t format_dns_reply
Definition: dns.h:201
Definition: dns.h:91
API common definitions See api_doc.md for more info.
int server_fails
Definition: dns.h:71
u32 random_seed
Definition: dns.h:120
int server_af
Definition: dns.h:70
f64 expiration_time
Expiration time.
Definition: dns.h:62
#define foreach_dns46_request_error
Definition: dns.h:136
dns46_request_error_t
Definition: dns.h:145
int is_enabled
enable / disable flag
Definition: dns.h:105
void vnet_dns_send_dns4_request(vlib_main_t *vm, dns_main_t *dm, dns_cache_entry_t *ep, ip4_address_t *server)
Definition: dns.c:221
dns_cache_entry_t * entries
Pool of cache entries.
Definition: dns.h:94