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 struct iwpm_nlmsg_request {
62 	struct list_head    inprocess_list;
63 	__u32               nlmsg_seq;
64 	void                *req_buffer;
65 	u8	            nl_client;
66 	u8                  request_done;
67 	u16                 err_code;
68 	wait_queue_head_t   waitq;
69 	struct kref         kref;
70 };
71 
72 struct iwpm_mapping_info {
73 	struct hlist_node hlist_node;
74 	struct sockaddr_storage local_sockaddr;
75 	struct sockaddr_storage mapped_sockaddr;
76 	u8     nl_client;
77 };
78 
79 struct iwpm_admin_data {
80 	atomic_t refcount;
81 	atomic_t nlmsg_seq;
82 	int      client_list[RDMA_NL_NUM_CLIENTS];
83 	int      reg_list[RDMA_NL_NUM_CLIENTS];
84 };
85 
86 /**
87  * iwpm_get_nlmsg_request - Allocate and initialize netlink message request
88  * @nlmsg_seq: Sequence number of the netlink message
89  * @nl_client: The index of the netlink client
90  * @gfp: Indicates how the memory for the request should be allocated
91  *
92  * Returns the newly allocated netlink request object if successful,
93  * otherwise returns NULL
94  */
95 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
96 						u8 nl_client, gfp_t gfp);
97 
98 /**
99  * iwpm_free_nlmsg_request - Deallocate netlink message request
100  * @kref: Holds reference of netlink message request
101  */
102 void iwpm_free_nlmsg_request(struct kref *kref);
103 
104 /**
105  * iwpm_find_nlmsg_request - Find netlink message request in the request list
106  * @echo_seq: Sequence number of the netlink request to find
107  *
108  * Returns the found netlink message request,
109  * if not found, returns NULL
110  */
111 struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq);
112 
113 /**
114  * iwpm_wait_complete_req - Block while servicing the netlink request
115  * @nlmsg_request: Netlink message request to service
116  *
117  * Wakes up, after the request is completed or expired
118  * Returns 0 if the request is complete without error
119  */
120 int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request);
121 
122 /**
123  * iwpm_get_nlmsg_seq - Get the sequence number for a netlink
124  *			message to send to the port mapper
125  *
126  * Returns the sequence number for the netlink message.
127  */
128 int iwpm_get_nlmsg_seq(void);
129 
130 /**
131  * iwpm_valid_client - Check if the port mapper client is valid
132  * @nl_client: The index of the netlink client
133  *
134  * Valid clients need to call iwpm_init() before using
135  * the port mapper
136  */
137 int iwpm_valid_client(u8 nl_client);
138 
139 /**
140  * iwpm_set_valid - Set the port mapper client to valid or not
141  * @nl_client: The index of the netlink client
142  * @valid: 1 if valid or 0 if invalid
143  */
144 void iwpm_set_valid(u8 nl_client, int valid);
145 
146 /**
147  * iwpm_registered_client - Check if the port mapper client is registered
148  * @nl_client: The index of the netlink client
149  *
150  * Call iwpm_register_pid() to register a client
151  */
152 int iwpm_registered_client(u8 nl_client);
153 
154 /**
155  * iwpm_set_registered - Set the port mapper client to registered or not
156  * @nl_client: The index of the netlink client
157  * @reg: 1 if registered or 0 if not
158  */
159 void iwpm_set_registered(u8 nl_client, int reg);
160 
161 /**
162  * iwpm_send_mapinfo - Send local and mapped IPv4/IPv6 address info of
163  *                     a client to the user space port mapper
164  * @nl_client: The index of the netlink client
165  * @iwpm_pid: The pid of the user space port mapper
166  *
167  * If successful, returns the number of sent mapping info records
168  */
169 int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid);
170 
171 /**
172  * iwpm_mapinfo_available - Check if any mapping info records is available
173  *		            in the hash table
174  *
175  * Returns 1 if mapping information is available, otherwise returns 0
176  */
177 int iwpm_mapinfo_available(void);
178 
179 /**
180  * iwpm_compare_sockaddr - Compare two sockaddr storage structs
181  *
182  * Returns 0 if they are holding the same ip/tcp address info,
183  * otherwise returns 1
184  */
185 int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
186 			struct sockaddr_storage *b_sockaddr);
187 
188 /**
189  * iwpm_validate_nlmsg_attr - Check for NULL netlink attributes
190  * @nltb: Holds address of each netlink message attributes
191  * @nla_count: Number of netlink message attributes
192  *
193  * Returns error if any of the nla_count attributes is NULL
194  */
195 static inline int iwpm_validate_nlmsg_attr(struct nlattr *nltb[],
196 					   int nla_count)
197 {
198 	int i;
199 	for (i = 1; i < nla_count; i++) {
200 		if (!nltb[i])
201 			return -EINVAL;
202 	}
203 	return 0;
204 }
205 
206 /**
207  * iwpm_create_nlmsg - Allocate skb and form a netlink message
208  * @nl_op: Netlink message opcode
209  * @nlh: Holds address of the netlink message header in skb
210  * @nl_client: The index of the netlink client
211  *
212  * Returns the newly allcated skb, or NULL if the tailroom of the skb
213  * is insufficient to store the message header and payload
214  */
215 struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
216 					int nl_client);
217 
218 /**
219  * iwpm_parse_nlmsg - Validate and parse the received netlink message
220  * @cb: Netlink callback structure
221  * @policy_max: Maximum attribute type to be expected
222  * @nlmsg_policy: Validation policy
223  * @nltb: Array to store policy_max parsed elements
224  * @msg_type: Type of netlink message
225  *
226  * Returns 0 on success or a negative error code
227  */
228 int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
229 				const struct nla_policy *nlmsg_policy,
230 				struct nlattr *nltb[], const char *msg_type);
231 
232 /**
233  * iwpm_print_sockaddr - Print IPv4/IPv6 address and TCP port
234  * @sockaddr: Socket address to print
235  * @msg: Message to print
236  */
237 void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg);
238 #endif
239