1 /*
2 * Copyright (c) 2019 Intel Corporation.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/logging/log.h>
8 LOG_MODULE_DECLARE(net_l2_ppp, CONFIG_NET_L2_PPP_LOG_LEVEL);
9
10 #include <zephyr/net/net_core.h>
11 #include <zephyr/net/net_l2.h>
12 #include <zephyr/net/net_if.h>
13 #include <zephyr/net/net_pkt.h>
14 #include <zephyr/net/net_mgmt.h>
15
16 #include <zephyr/net/ppp.h>
17
18 #include "net_private.h"
19
20 #include "ppp_stats.h"
21 #include "ppp_internal.h"
22
lcp_handle_ext(struct ppp_fsm * fsm,enum ppp_packet_type code,uint8_t id,struct net_pkt * pkt)23 static enum net_verdict lcp_handle_ext(struct ppp_fsm *fsm,
24 enum ppp_packet_type code, uint8_t id,
25 struct net_pkt *pkt)
26 {
27 enum net_verdict verdict = NET_DROP;
28
29 switch (code) {
30 case PPP_PROTOCOL_REJ:
31 NET_DBG("PPP Protocol-Rej");
32 return ppp_fsm_recv_protocol_rej(fsm, id, pkt);
33
34 case PPP_ECHO_REQ:
35 NET_DBG("PPP Echo-Req");
36 return ppp_fsm_recv_echo_req(fsm, id, pkt);
37
38 case PPP_ECHO_REPLY:
39 NET_DBG("PPP Echo-Reply");
40 return ppp_fsm_recv_echo_reply(fsm, id, pkt);
41
42 case PPP_DISCARD_REQ:
43 NET_DBG("PPP Discard-Req");
44 return ppp_fsm_recv_discard_req(fsm, id, pkt);
45
46 default:
47 break;
48 }
49
50 return verdict;
51 }
52
lcp_handle(struct ppp_context * ctx,struct net_if * iface,struct net_pkt * pkt)53 static enum net_verdict lcp_handle(struct ppp_context *ctx,
54 struct net_if *iface,
55 struct net_pkt *pkt)
56 {
57 return ppp_fsm_input(&ctx->lcp.fsm, PPP_LCP, pkt);
58 }
59
60 struct lcp_option_data {
61 bool auth_proto_present;
62 uint16_t auth_proto;
63 };
64
65 static const enum ppp_protocol_type lcp_supported_auth_protos[] = {
66 #if defined(CONFIG_NET_L2_PPP_PAP)
67 PPP_PAP,
68 #endif
69 };
70
lcp_auth_proto_parse(struct ppp_fsm * fsm,struct net_pkt * pkt,void * user_data)71 static int lcp_auth_proto_parse(struct ppp_fsm *fsm, struct net_pkt *pkt,
72 void *user_data)
73 {
74 struct lcp_option_data *data = user_data;
75 int ret;
76 int i;
77
78 ret = net_pkt_read_be16(pkt, &data->auth_proto);
79 if (ret < 0) {
80 /* Should not happen, is the pkt corrupt? */
81 return -EMSGSIZE;
82 }
83
84 NET_DBG("[LCP] Received auth protocol %x (%s)",
85 (unsigned int) data->auth_proto,
86 ppp_proto2str(data->auth_proto));
87
88 for (i = 0; i < ARRAY_SIZE(lcp_supported_auth_protos); i++) {
89 if (data->auth_proto == lcp_supported_auth_protos[i]) {
90 data->auth_proto_present = true;
91 return 0;
92 }
93 }
94
95 return -EINVAL;
96 }
97
lcp_auth_proto_nack(struct ppp_fsm * fsm,struct net_pkt * ret_pkt,void * user_data)98 static int lcp_auth_proto_nack(struct ppp_fsm *fsm, struct net_pkt *ret_pkt,
99 void *user_data)
100 {
101 (void)net_pkt_write_u8(ret_pkt, LCP_OPTION_AUTH_PROTO);
102 (void)net_pkt_write_u8(ret_pkt, 4);
103 return net_pkt_write_be16(ret_pkt, PPP_PAP);
104 }
105
106 static const struct ppp_peer_option_info lcp_peer_options[] = {
107 PPP_PEER_OPTION(LCP_OPTION_AUTH_PROTO, lcp_auth_proto_parse,
108 lcp_auth_proto_nack),
109 };
110
lcp_config_info_req(struct ppp_fsm * fsm,struct net_pkt * pkt,uint16_t length,struct net_pkt * ret_pkt)111 static int lcp_config_info_req(struct ppp_fsm *fsm,
112 struct net_pkt *pkt,
113 uint16_t length,
114 struct net_pkt *ret_pkt)
115 {
116 struct ppp_context *ctx = CONTAINER_OF(fsm, struct ppp_context,
117 lcp.fsm);
118 struct lcp_option_data data = {
119 .auth_proto_present = false,
120 };
121 int ret;
122
123 ret = ppp_config_info_req(fsm, pkt, length, ret_pkt, PPP_LCP,
124 lcp_peer_options,
125 ARRAY_SIZE(lcp_peer_options),
126 &data);
127 if (ret != PPP_CONFIGURE_ACK) {
128 /* There are some issues with configuration still */
129 return ret;
130 }
131
132 ctx->lcp.peer_options.auth_proto = data.auth_proto;
133
134 if (data.auth_proto_present) {
135 NET_DBG("Authentication protocol negotiated: %x (%s)",
136 (unsigned int) data.auth_proto,
137 ppp_proto2str(data.auth_proto));
138 }
139
140 return PPP_CONFIGURE_ACK;
141 }
142
lcp_lower_down(struct ppp_context * ctx)143 static void lcp_lower_down(struct ppp_context *ctx)
144 {
145 ppp_fsm_lower_down(&ctx->lcp.fsm);
146 }
147
lcp_lower_up(struct ppp_context * ctx)148 static void lcp_lower_up(struct ppp_context *ctx)
149 {
150 #if defined(CONFIG_NET_L2_PPP_OPTION_MRU)
151 /* Get currently set MTU */
152 ctx->lcp.my_options.mru = net_if_get_mtu(ctx->iface);
153 #endif
154
155 ppp_fsm_lower_up(&ctx->lcp.fsm);
156 }
157
lcp_open(struct ppp_context * ctx)158 static void lcp_open(struct ppp_context *ctx)
159 {
160 ppp_fsm_open(&ctx->lcp.fsm);
161 }
162
lcp_close(struct ppp_context * ctx,const uint8_t * reason)163 static void lcp_close(struct ppp_context *ctx, const uint8_t *reason)
164 {
165 if (ctx->phase != PPP_DEAD) {
166 ppp_change_phase(ctx, PPP_TERMINATE);
167 }
168
169 ppp_fsm_close(&ctx->lcp.fsm, reason);
170 }
171
lcp_down(struct ppp_fsm * fsm)172 static void lcp_down(struct ppp_fsm *fsm)
173 {
174 struct ppp_context *ctx = CONTAINER_OF(fsm, struct ppp_context,
175 lcp.fsm);
176
177 memset(&ctx->lcp.peer_options.auth_proto, 0,
178 sizeof(ctx->lcp.peer_options.auth_proto));
179
180 ppp_link_down(ctx);
181
182 if (net_if_is_carrier_ok(ctx->iface) && ctx->is_enabled) {
183 ppp_change_phase(ctx, PPP_ESTABLISH);
184 }
185 }
186
lcp_up(struct ppp_fsm * fsm)187 static void lcp_up(struct ppp_fsm *fsm)
188 {
189 struct ppp_context *ctx = CONTAINER_OF(fsm, struct ppp_context,
190 lcp.fsm);
191
192 /* TODO: Set MRU/MTU of the network interface here */
193
194 ppp_link_established(ctx, fsm);
195 }
196
lcp_starting(struct ppp_fsm * fsm)197 static void lcp_starting(struct ppp_fsm *fsm)
198 {
199 struct ppp_context *ctx = CONTAINER_OF(fsm, struct ppp_context,
200 lcp.fsm);
201
202 ppp_link_needed(ctx);
203 }
204
lcp_finished(struct ppp_fsm * fsm)205 static void lcp_finished(struct ppp_fsm *fsm)
206 {
207 struct ppp_context *ctx = CONTAINER_OF(fsm, struct ppp_context,
208 lcp.fsm);
209
210 ppp_link_terminated(ctx);
211 }
212
213 #if defined(CONFIG_NET_L2_PPP_OPTION_MRU)
214
215 #define MRU_OPTION_LEN 4
216
lcp_add_mru(struct ppp_context * ctx,struct net_pkt * pkt)217 static int lcp_add_mru(struct ppp_context *ctx, struct net_pkt *pkt)
218 {
219 net_pkt_write_u8(pkt, MRU_OPTION_LEN);
220 return net_pkt_write_be16(pkt, ctx->lcp.my_options.mru);
221 }
222
lcp_ack_mru(struct ppp_context * ctx,struct net_pkt * pkt,uint8_t oplen)223 static int lcp_ack_mru(struct ppp_context *ctx, struct net_pkt *pkt,
224 uint8_t oplen)
225 {
226 int ret;
227 uint16_t mru;
228
229 /* Handle ACK : */
230 if (oplen != sizeof(mru)) {
231 return -EINVAL;
232 }
233
234 ret = net_pkt_read(pkt, &mru, sizeof(mru));
235 if (ret) {
236 return ret;
237 }
238 if (mru != ctx->lcp.my_options.mru) {
239 /* Didn't acked our MRU: */
240 return -EINVAL;
241 }
242
243 return 0;
244 }
245
lcp_nak_mru(struct ppp_context * ctx,struct net_pkt * pkt,uint8_t oplen)246 static int lcp_nak_mru(struct ppp_context *ctx, struct net_pkt *pkt,
247 uint8_t oplen)
248 {
249 int ret;
250 uint16_t mru;
251
252 /* Handle NAK: accept only smaller/equal than ours */
253 if (oplen != sizeof(mru)) {
254 return -EINVAL;
255 }
256
257 ret = net_pkt_read(pkt, &mru, sizeof(mru));
258 if (ret) {
259 return ret;
260 }
261
262 if (mru <= ctx->lcp.my_options.mru) {
263 /* OK, reset the MRU also in our side: */
264 ctx->lcp.my_options.mru = mru;
265 } else {
266 return -EINVAL;
267 }
268
269 return 0;
270 }
271
272 static const struct ppp_my_option_info lcp_my_options[] = {
273 PPP_MY_OPTION(LCP_OPTION_MRU, lcp_add_mru, lcp_ack_mru, lcp_nak_mru),
274 };
275 BUILD_ASSERT(ARRAY_SIZE(lcp_my_options) == LCP_NUM_MY_OPTIONS);
276
lcp_config_info_add(struct ppp_fsm * fsm)277 static struct net_pkt *lcp_config_info_add(struct ppp_fsm *fsm)
278 {
279 return ppp_my_options_add(fsm, MRU_OPTION_LEN);
280 }
281
lcp_config_info_nack(struct ppp_fsm * fsm,struct net_pkt * pkt,uint16_t length,bool rejected)282 static int lcp_config_info_nack(struct ppp_fsm *fsm, struct net_pkt *pkt,
283 uint16_t length, bool rejected)
284 {
285 struct ppp_context *ctx =
286 CONTAINER_OF(fsm, struct ppp_context, lcp.fsm);
287 int ret;
288
289 ret = ppp_my_options_parse_conf_nak(fsm, pkt, length);
290 if (ret) {
291 return ret;
292 }
293
294 if (!ctx->lcp.my_options.mru) {
295 return -EINVAL;
296 }
297
298 return 0;
299 }
300 #endif
301
lcp_init(struct ppp_context * ctx)302 static void lcp_init(struct ppp_context *ctx)
303 {
304 NET_DBG("proto %s (0x%04x) fsm %p", ppp_proto2str(PPP_LCP), PPP_LCP,
305 &ctx->lcp.fsm);
306
307 memset(&ctx->lcp.fsm, 0, sizeof(ctx->lcp.fsm));
308
309 ppp_fsm_init(&ctx->lcp.fsm, PPP_LCP);
310
311 ppp_fsm_name_set(&ctx->lcp.fsm, ppp_proto2str(PPP_LCP));
312
313 ctx->lcp.my_options.mru = net_if_get_mtu(ctx->iface);
314
315 #if defined(CONFIG_NET_L2_PPP_OPTION_MRU)
316 ctx->lcp.fsm.my_options.info = lcp_my_options;
317 ctx->lcp.fsm.my_options.data = ctx->lcp.my_options_data;
318 ctx->lcp.fsm.my_options.count = ARRAY_SIZE(lcp_my_options);
319
320 ctx->lcp.fsm.cb.config_info_add = lcp_config_info_add;
321 ctx->lcp.fsm.cb.config_info_req = lcp_config_info_req;
322 ctx->lcp.fsm.cb.config_info_nack = lcp_config_info_nack;
323 ctx->lcp.fsm.cb.config_info_rej = ppp_my_options_parse_conf_rej;
324 #endif
325
326 ctx->lcp.fsm.cb.up = lcp_up;
327 ctx->lcp.fsm.cb.down = lcp_down;
328 ctx->lcp.fsm.cb.starting = lcp_starting;
329 ctx->lcp.fsm.cb.finished = lcp_finished;
330 if (IS_ENABLED(CONFIG_NET_L2_PPP_AUTH_SUPPORT)) {
331 ctx->lcp.fsm.cb.config_info_req = lcp_config_info_req;
332 }
333 ctx->lcp.fsm.cb.proto_extension = lcp_handle_ext;
334 }
335
336 PPP_PROTOCOL_REGISTER(LCP, PPP_LCP,
337 lcp_init, lcp_handle,
338 lcp_lower_up, lcp_lower_down,
339 lcp_open, lcp_close);
340
