xref: /aosp_15_r20/external/libnl/lib/route/link/ppp.c (revision 4dc78e53d49367fa8e61b07018507c90983a077d)
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3  * Copyright (c) 2016 Jonas Johansson <[email protected]>
4  */
5 
6 /**
7  * @ingroup link
8  * @defgroup ppp PPP
9  *
10  * @details
11  * \b Link Type Name: "ppp"
12  *
13  * @route_doc{link_ppp, PPP Documentation}
14  * @{
15  */
16 
17 #include "nl-default.h"
18 
19 #include <netlink/route/link/ppp.h>
20 #include <netlink/netlink.h>
21 
22 #include "nl-route.h"
23 #include "link-api.h"
24 
25 /** @cond SKIP */
26 #define PPP_ATTR_FD		(1<<0)
27 
28 struct ppp_info
29 {
30 	int32_t			pi_fd;
31 	uint32_t		ce_mask;
32 };
33 
34 /** @endcond */
35 
36 static struct nla_policy ppp_nl_policy[IFLA_PPP_MAX+1] = {
37 	[IFLA_PPP_DEV_FD]	= { .type = NLA_S32 },
38 };
39 
ppp_alloc(struct rtnl_link * link)40 static int ppp_alloc(struct rtnl_link *link)
41 {
42 	struct ppp_info *info;
43 
44 	if (link->l_info)
45 		memset(link->l_info, 0, sizeof(*info));
46 	else {
47 		if ((info = calloc(1, sizeof(*info))) == NULL)
48 			return -NLE_NOMEM;
49 
50 		link->l_info = info;
51 	}
52 
53 	return 0;
54 }
55 
ppp_parse(struct rtnl_link * link,struct nlattr * data,struct nlattr * xstats)56 static int ppp_parse(struct rtnl_link *link, struct nlattr *data,
57                          struct nlattr *xstats)
58 {
59 	struct nlattr *tb[IFLA_PPP_MAX+1];
60 	struct ppp_info *info;
61 	int err;
62 
63 	NL_DBG(3, "Parsing PPP link info\n");
64 
65 	if ((err = nla_parse_nested(tb, IFLA_PPP_MAX, data, ppp_nl_policy)) < 0)
66 		goto errout;
67 
68 	if ((err = ppp_alloc(link)) < 0)
69 		goto errout;
70 
71 	info = link->l_info;
72 
73 	if (tb[IFLA_PPP_DEV_FD]) {
74 		info->pi_fd = nla_get_s32(tb[IFLA_PPP_DEV_FD]);
75 		info->ce_mask |= PPP_ATTR_FD;
76 	}
77 
78 	err = 0;
79 errout:
80 	return err;
81 }
82 
ppp_free(struct rtnl_link * link)83 static void ppp_free(struct rtnl_link *link)
84 {
85 	free(link->l_info);
86 	link->l_info = NULL;
87 }
88 
ppp_clone(struct rtnl_link * dst,struct rtnl_link * src)89 static int ppp_clone(struct rtnl_link *dst, struct rtnl_link *src)
90 {
91 	struct ppp_info *vdst, *vsrc = src->l_info;
92 	int err;
93 
94 	dst->l_info = NULL;
95 	if ((err = rtnl_link_set_type(dst, "ppp")) < 0)
96 		return err;
97 	vdst = dst->l_info;
98 
99 	if (!vdst || !vsrc)
100 		return -NLE_NOMEM;
101 
102 	memcpy(vdst, vsrc, sizeof(struct ppp_info));
103 
104 	return 0;
105 }
106 
ppp_put_attrs(struct nl_msg * msg,struct rtnl_link * link)107 static int ppp_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
108 {
109 	struct ppp_info *info = link->l_info;
110 	struct nlattr *data;
111 
112 	if (!(data = nla_nest_start(msg, IFLA_INFO_DATA)))
113 		return -NLE_MSGSIZE;
114 
115 	if (info->ce_mask & PPP_ATTR_FD)
116 		NLA_PUT_S32(msg, IFLA_PPP_DEV_FD, info->pi_fd);
117 
118 	nla_nest_end(msg, data);
119 
120 nla_put_failure:
121 
122 	return 0;
123 }
124 
125 static struct rtnl_link_info_ops ppp_info_ops = {
126 	.io_name		= "ppp",
127 	.io_alloc		= ppp_alloc,
128 	.io_parse		= ppp_parse,
129 	.io_clone		= ppp_clone,
130 	.io_put_attrs		= ppp_put_attrs,
131 	.io_free		= ppp_free,
132 };
133 
134 /** @cond SKIP */
135 #define IS_PPP_LINK_ASSERT(link) \
136 	if ((link)->l_info_ops != &ppp_info_ops) { \
137 		APPBUG("Link is not a PPP link. set type \"ppp\" first."); \
138 		return -NLE_OPNOTSUPP; \
139 	}
140 /** @endcond */
141 
142 /**
143  * @name PPP Object
144  * @{
145  */
146 
147 /**
148  * Allocate link object of type PPP
149  *
150  * @return Allocated link object or NULL.
151  */
rtnl_link_ppp_alloc(void)152 struct rtnl_link *rtnl_link_ppp_alloc(void)
153 {
154 	struct rtnl_link *link;
155 
156 	if (!(link = rtnl_link_alloc()))
157 		return NULL;
158 
159 	if (rtnl_link_set_type(link, "ppp") < 0) {
160 		rtnl_link_put(link);
161 		return NULL;
162 	}
163 
164 	return link;
165 }
166 
167 /**
168  * Set PPP file descriptor
169  * @arg link		Link object
170  * @arg flags		PPP file descriptor
171  *
172  * @return 0 on success or a negative error code.
173  */
rtnl_link_ppp_set_fd(struct rtnl_link * link,int32_t fd)174 int rtnl_link_ppp_set_fd(struct rtnl_link *link, int32_t fd)
175 {
176 	struct ppp_info *info = link->l_info;
177 
178 	IS_PPP_LINK_ASSERT(link);
179 
180 	info->pi_fd |= fd;
181 	info->ce_mask |= PPP_ATTR_FD;
182 
183 	return 0;
184 }
185 
186 /**
187  * Get PPP file descriptor
188  * @arg link		Link object
189  *
190  * @return PPP file descriptor, 0 if not set or a negative error code.
191  */
rtnl_link_ppp_get_fd(struct rtnl_link * link,int32_t * fd)192 int rtnl_link_ppp_get_fd(struct rtnl_link *link, int32_t *fd)
193 {
194 	struct ppp_info *info = link->l_info;
195 
196 	IS_PPP_LINK_ASSERT(link);
197 
198 	if (!(info->ce_mask & PPP_ATTR_FD))
199 		return -NLE_NOATTR;
200 
201 	if (fd)
202 		*fd = info->pi_fd;
203 
204 	return 0;
205 }
206 
207 /** @} */
208 
ppp_init(void)209 static void _nl_init ppp_init(void)
210 {
211 	rtnl_link_register_info(&ppp_info_ops);
212 }
213 
ppp_exit(void)214 static void _nl_exit ppp_exit(void)
215 {
216 	rtnl_link_unregister_info(&ppp_info_ops);
217 }
218 
219 /** @} */
220