1 /*
2  * Copyright (c) 2014 Intel Corporation. All rights reserved.
3  * Copyright (c) 2014 Chelsio, Inc. All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *	  copyright notice, this list of conditions and the following
17  *	  disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *	  copyright notice, this list of conditions and the following
21  *	  disclaimer in the documentation and/or other materials
22  *	  provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 #ifndef _IWPM_UTIL_H
34 #define _IWPM_UTIL_H
35 
36 #include <linux/module.h>
37 #include <linux/io.h>
38 #include <linux/in.h>
39 #include <linux/in6.h>
40 #include <linux/spinlock.h>
41 #include <linux/kernel.h>
42 #include <linux/netdevice.h>
43 #include <linux/delay.h>
44 #include <linux/workqueue.h>
45 #include <linux/mutex.h>
46 #include <linux/jhash.h>
47 #include <linux/kref.h>
48 #include <net/netlink.h>
49 #include <linux/errno.h>
50 #include <rdma/iw_portmap.h>
51 #include <rdma/rdma_netlink.h>
52 
53 
54 #define IWPM_NL_RETRANS		3
55 #define IWPM_NL_TIMEOUT		(10*HZ)
56 #define IWPM_MAPINFO_SKB_COUNT	20
57 
58 #define IWPM_PID_UNDEFINED     -1
59 #define IWPM_PID_UNAVAILABLE   -2
60 
61 #define IWPM_REG_UNDEF          0x01
62 #define IWPM_REG_VALID          0x02
63 #define IWPM_REG_INCOMPL        0x04
64 
65 struct iwpm_nlmsg_request {
66 	struct list_head    inprocess_list;
67 	__u32               nlmsg_seq;
68 	void                *req_buffer;
69 	u8	            nl_client;
70 	u8                  request_done;
71 	u16                 err_code;
72 	struct semaphore    sem;
73 	struct kref         kref;
74 };
75 
76 struct iwpm_mapping_info {
77 	struct hlist_node hlist_node;
78 	struct sockaddr_storage local_sockaddr;
79 	struct sockaddr_storage mapped_sockaddr;
80 	u8     nl_client;
81 };
82 
83 struct iwpm_remote_info {
84 	struct hlist_node hlist_node;
85 	struct sockaddr_storage remote_sockaddr;
86 	struct sockaddr_storage mapped_loc_sockaddr;
87 	struct sockaddr_storage mapped_rem_sockaddr;
88 	u8     nl_client;
89 };
90 
91 struct iwpm_admin_data {
92 	atomic_t refcount;
93 	atomic_t nlmsg_seq;
94 	int      client_list[RDMA_NL_NUM_CLIENTS];
95 	u32      reg_list[RDMA_NL_NUM_CLIENTS];
96 };
97 
98 /**
99  * iwpm_get_nlmsg_request - Allocate and initialize netlink message request
100  * @nlmsg_seq: Sequence number of the netlink message
101  * @nl_client: The index of the netlink client
102  * @gfp: Indicates how the memory for the request should be allocated
103  *
104  * Returns the newly allocated netlink request object if successful,
105  * otherwise returns NULL
106  */
107 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
108 						u8 nl_client, gfp_t gfp);
109 
110 /**
111  * iwpm_free_nlmsg_request - Deallocate netlink message request
112  * @kref: Holds reference of netlink message request
113  */
114 void iwpm_free_nlmsg_request(struct kref *kref);
115 
116 /**
117  * iwpm_find_nlmsg_request - Find netlink message request in the request list
118  * @echo_seq: Sequence number of the netlink request to find
119  *
120  * Returns the found netlink message request,
121  * if not found, returns NULL
122  */
123 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq);
124 
125 /**
126  * iwpm_wait_complete_req - Block while servicing the netlink request
127  * @nlmsg_request: Netlink message request to service
128  *
129  * Wakes up, after the request is completed or expired
130  * Returns 0 if the request is complete without error
131  */
132 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request);
133 
134 /**
135  * iwpm_get_nlmsg_seq - Get the sequence number for a netlink
136  *			message to send to the port mapper
137  *
138  * Returns the sequence number for the netlink message.
139  */
140 int iwpm_get_nlmsg_seq(void);
141 
142 /**
143  * iwpm_add_reminfo - Add remote address info of the connecting peer
144  *                    to the remote info hash table
145  * @reminfo: The remote info to be added
146  */
147 void iwpm_add_remote_info(struct iwpm_remote_info *reminfo);
148 
149 /**
150  * iwpm_valid_client - Check if the port mapper client is valid
151  * @nl_client: The index of the netlink client
152  *
153  * Valid clients need to call iwpm_init() before using
154  * the port mapper
155  */
156 int iwpm_valid_client(u8 nl_client);
157 
158 /**
159  * iwpm_set_valid - Set the port mapper client to valid or not
160  * @nl_client: The index of the netlink client
161  * @valid: 1 if valid or 0 if invalid
162  */
163 void iwpm_set_valid(u8 nl_client, int valid);
164 
165 /**
166  * iwpm_check_registration - Check if the client registration
167  *			      matches the given one
168  * @nl_client: The index of the netlink client
169  * @reg: The given registration type to compare with
170  *
171  * Call iwpm_register_pid() to register a client
172  * Returns true if the client registration matches reg,
173  * otherwise returns false
174  */
175 u32 iwpm_check_registration(u8 nl_client, u32 reg);
176 
177 /**
178  * iwpm_set_registration - Set the client registration
179  * @nl_client: The index of the netlink client
180  * @reg: Registration type to set
181  */
182 void iwpm_set_registration(u8 nl_client, u32 reg);
183 
184 /**
185  * iwpm_get_registration
186  * @nl_client: The index of the netlink client
187  *
188  * Returns the client registration type
189  */
190 u32 iwpm_get_registration(u8 nl_client);
191 
192 /**
193  * iwpm_send_mapinfo - Send local and mapped IPv4/IPv6 address info of
194  *                     a client to the user space port mapper
195  * @nl_client: The index of the netlink client
196  * @iwpm_pid: The pid of the user space port mapper
197  *
198  * If successful, returns the number of sent mapping info records
199  */
200 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid);
201 
202 /**
203  * iwpm_mapinfo_available - Check if any mapping info records is available
204  *		            in the hash table
205  *
206  * Returns 1 if mapping information is available, otherwise returns 0
207  */
208 int iwpm_mapinfo_available(void);
209 
210 /**
211  * iwpm_compare_sockaddr - Compare two sockaddr storage structs
212  *
213  * Returns 0 if they are holding the same ip/tcp address info,
214  * otherwise returns 1
215  */
216 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
217 			struct sockaddr_storage *b_sockaddr);
218 
219 /**
220  * iwpm_validate_nlmsg_attr - Check for NULL netlink attributes
221  * @nltb: Holds address of each netlink message attributes
222  * @nla_count: Number of netlink message attributes
223  *
224  * Returns error if any of the nla_count attributes is NULL
225  */
226 static inline int iwpm_validate_nlmsg_attr(struct nlattr *nltb[],
227 					   int nla_count)
228 {
229 	int i;
230 	for (i = 1; i < nla_count; i++) {
231 		if (!nltb[i])
232 			return -EINVAL;
233 	}
234 	return 0;
235 }
236 
237 /**
238  * iwpm_create_nlmsg - Allocate skb and form a netlink message
239  * @nl_op: Netlink message opcode
240  * @nlh: Holds address of the netlink message header in skb
241  * @nl_client: The index of the netlink client
242  *
243  * Returns the newly allcated skb, or NULL if the tailroom of the skb
244  * is insufficient to store the message header and payload
245  */
246 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
247 					int nl_client);
248 
249 /**
250  * iwpm_parse_nlmsg - Validate and parse the received netlink message
251  * @cb: Netlink callback structure
252  * @policy_max: Maximum attribute type to be expected
253  * @nlmsg_policy: Validation policy
254  * @nltb: Array to store policy_max parsed elements
255  * @msg_type: Type of netlink message
256  *
257  * Returns 0 on success or a negative error code
258  */
259 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
260 				const struct nla_policy *nlmsg_policy,
261 				struct nlattr *nltb[], const char *msg_type);
262 
263 /**
264  * iwpm_print_sockaddr - Print IPv4/IPv6 address and TCP port
265  * @sockaddr: Socket address to print
266  * @msg: Message to print
267  */
268 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg);
269 #endif
270