summaryrefslogtreecommitdiff
path: root/accel-pppd/auth/auth_pap.c
blob: ebbc64fc707d87466ae5bbb0e52710809d449f8c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>

#include "log.h"
#include "events.h"
#include "ppp.h"
#include "ppp_auth.h"
#include "ppp_lcp.h"
#include "pwdb.h"

#include "memdebug.h"

#define MSG_FAILED "Authentication failed"
#define MSG_SUCCESSED "Authentication succeeded"

#define HDR_LEN (sizeof(struct pap_hdr_t)-2)

#define PAP_REQ 1
#define PAP_ACK 2
#define PAP_NAK 3

static int conf_timeout = 5;
static int conf_any_login = 0;

static struct auth_data_t* auth_data_init(struct ppp_t *ppp);
static void auth_data_free(struct ppp_t*, struct auth_data_t*);
static int lcp_send_conf_req(struct ppp_t*, struct auth_data_t*, uint8_t*);
static int lcp_recv_conf_req(struct ppp_t*, struct auth_data_t*, uint8_t*);
static int pap_start(struct ppp_t*, struct auth_data_t*);
static int pap_finish(struct ppp_t*, struct auth_data_t*);
static void pap_recv(struct ppp_handler_t*h);
static void pap_timeout(struct triton_timer_t *t);

struct pap_auth_data_t
{
	struct auth_data_t auth;
	struct ppp_handler_t h;
	struct ppp_t *ppp;
	int started:1;
	struct triton_timer_t timeout;
};

struct pap_hdr_t
{
	uint16_t proto;
	uint8_t code;
	uint8_t id;
	uint16_t len;
} __attribute__((packed));

struct pap_ack_t
{
	struct pap_hdr_t hdr;
	uint8_t msg_len;
	char msg[0];
} __attribute__((packed));

static struct ppp_auth_handler_t pap=
{
	.name          = "PAP",
	.init          = auth_data_init,
	.free          = auth_data_free,
	.send_conf_req = lcp_send_conf_req,
	.recv_conf_req = lcp_recv_conf_req,
	.start         = pap_start,
	.finish        = pap_finish,
};

static struct auth_data_t* auth_data_init(struct ppp_t *ppp)
{
	struct pap_auth_data_t *d = _malloc(sizeof(*d));

	memset(d, 0, sizeof(*d));
	d->auth.proto = PPP_PAP;
	d->ppp = ppp;

	return &d->auth;
}

static void auth_data_free(struct ppp_t *ppp, struct auth_data_t *auth)
{
	struct pap_auth_data_t *d = container_of(auth, typeof(*d), auth);

	_free(d);
}

static int pap_start(struct ppp_t *ppp, struct auth_data_t *auth)
{
	struct pap_auth_data_t *d = container_of(auth, typeof(*d), auth);

	d->h.proto = PPP_PAP;
	d->h.recv = pap_recv;
	d->timeout.expire = pap_timeout;
	d->timeout.period = conf_timeout * 1000;

	triton_timer_add(ppp->ses.ctrl->ctx, &d->timeout, 0);

	ppp_register_chan_handler(ppp, &d->h);

	return 0;
}
static int pap_finish(struct ppp_t *ppp, struct auth_data_t *auth)
{
	struct pap_auth_data_t *d = container_of(auth, typeof(*d), auth);
	
	if (d->timeout.tpd)
		triton_timer_del(&d->timeout);

	ppp_unregister_handler(ppp, &d->h);

	return 0;
}

static void pap_timeout(struct triton_timer_t *t)
{
	struct pap_auth_data_t *d = container_of(t, typeof(*d), timeout);

	if (conf_ppp_verbose)
		log_ppp_warn("pap: timeout\n");

	ppp_auth_failed(d->ppp, NULL);
}

static int lcp_send_conf_req(struct ppp_t *ppp, struct auth_data_t *d, uint8_t *ptr)
{
	return 0;
}

static int lcp_recv_conf_req(struct ppp_t *ppp, struct auth_data_t *d, uint8_t *ptr)
{
	return LCP_OPT_ACK;
}

static void pap_send_ack(struct pap_auth_data_t *p, int id)
{
	uint8_t buf[128];
	struct pap_ack_t *msg = (struct pap_ack_t*)buf;
	msg->hdr.proto = htons(PPP_PAP);
	msg->hdr.code = PAP_ACK;
	msg->hdr.id = id;
	msg->hdr.len = htons(HDR_LEN + 1 + sizeof(MSG_SUCCESSED) - 1);
	msg->msg_len = sizeof(MSG_SUCCESSED) - 1;
	memcpy(msg->msg, MSG_SUCCESSED, sizeof(MSG_SUCCESSED));
	
	if (conf_ppp_verbose)
		log_ppp_info2("send [PAP AuthAck id=%x \"%s\"]\n", id, MSG_SUCCESSED);
	
	ppp_chan_send(p->ppp, msg, ntohs(msg->hdr.len) + 2);
}

static void pap_send_nak(struct pap_auth_data_t *p, int id)
{
	uint8_t buf[128];
	struct pap_ack_t *msg = (struct pap_ack_t*)buf;
	msg->hdr.proto = htons(PPP_PAP);
	msg->hdr.code = PAP_NAK;
	msg->hdr.id = id;
	msg->hdr.len = htons(HDR_LEN + 1 + sizeof(MSG_FAILED) - 1);
	msg->msg_len = sizeof(MSG_FAILED) - 1;
	memcpy(msg->msg, MSG_FAILED, sizeof(MSG_FAILED));
	
	if (conf_ppp_verbose)
		log_ppp_info2("send [PAP AuthNak id=%x \"%s\"]\n", id, MSG_FAILED);
	
	ppp_chan_send(p->ppp, msg, ntohs(msg->hdr.len) + 2);
}

static int pap_recv_req(struct pap_auth_data_t *p, struct pap_hdr_t *hdr)
{
	int ret, r;
	char *peer_id;
	char *passwd;
	char *passwd2;
	int peer_id_len;
	int passwd_len;
	uint8_t *ptr = (uint8_t*)(hdr + 1);

	if (p->timeout.tpd)
		triton_timer_del(&p->timeout);

	if (conf_ppp_verbose)
		log_ppp_info2("recv [PAP AuthReq id=%x]\n", hdr->id);

	peer_id_len = *(uint8_t*)ptr; ptr++;
	if (peer_id_len > ntohs(hdr->len) - sizeof(*hdr) + 2 - 1) {
		log_ppp_warn("PAP: short packet received\n");
		return -1;
	}
	peer_id = (char*)ptr; ptr += peer_id_len;

	passwd_len = *(uint8_t*)ptr; ptr++;
	if (passwd_len > ntohs(hdr->len) - sizeof(*hdr ) + 2 - 2 - peer_id_len) {
		log_ppp_warn("PAP: short packet received\n");
		return -1;
	}

	peer_id = _strndup((const char*)peer_id, peer_id_len);
	
	if (conf_any_login) {
		if (ppp_auth_succeeded(p->ppp, peer_id)) {
			pap_send_nak(p, hdr->id);
			ap_session_terminate(&p->ppp->ses, TERM_AUTH_ERROR, 0);
			_free(peer_id);
			return -1;
		}
		pap_send_ack(p, hdr->id);
		p->started = 1;
		return 0;
	}

	passwd = _strndup((const char*)ptr, passwd_len);

	r = pwdb_check(&p->ppp->ses, peer_id, PPP_PAP, passwd);
	if (r == PWDB_NO_IMPL) {
		passwd2 = pwdb_get_passwd(&p->ppp->ses, peer_id);
		if (!passwd2) {
			if (conf_ppp_verbose)
				log_ppp_warn("pap: user not found\n");
			goto failed;
		}

		if (strcmp(passwd2, passwd))
			r = PWDB_DENIED;
		else
			r = PWDB_SUCCESS;

		_free(passwd2);
	}

	if (r == PWDB_DENIED) {
		goto failed;
	} else {
		if (ppp_auth_succeeded(p->ppp, peer_id)) {
			pap_send_nak(p, hdr->id);
			ap_session_terminate(&p->ppp->ses, TERM_AUTH_ERROR, 0);
			_free(peer_id);
			ret = -1;
		} else {
			pap_send_ack(p, hdr->id);
			p->started = 1;
			ret = 0;
		}
	}

	_free(passwd);

	return 0;
		
failed:
	pap_send_nak(p, hdr->id);
	if (p->started)
		ap_session_terminate(&p->ppp->ses, TERM_AUTH_ERROR, 0);
	else
		ppp_auth_failed(p->ppp, peer_id);
	
	_free(passwd);
	_free(peer_id);
	
	return -1;
}

static void pap_recv(struct ppp_handler_t *h)
{
	struct pap_auth_data_t *d = container_of(h, typeof(*d), h);
	struct pap_hdr_t *hdr = (struct pap_hdr_t *)d->ppp->buf;

	if (d->ppp->buf_size < sizeof(*hdr) || ntohs(hdr->len) < HDR_LEN || ntohs(hdr->len) < d->ppp->buf_size - 2)	{
		log_ppp_warn("PAP: short packet received\n");
		return;
	}

	if (hdr->code == PAP_REQ)
		pap_recv_req(d, hdr);
	else {
		log_ppp_warn("PAP: unknown code received %x\n",hdr->code);
	}
}

static void load_config(void)
{
	const char *opt;

	opt = conf_get_opt("auth", "timeout");
	if (opt && atoi(opt) > 0)
		conf_timeout = atoi(opt);

	opt = conf_get_opt("auth", "any-login");
	if (opt)
		conf_any_login = atoi(opt);
}

static void auth_pap_init()
{
	load_config();

	ppp_auth_register_handler(&pap);

	triton_event_register_handler(EV_CONFIG_RELOAD, (triton_event_func)load_config);
}

DEFINE_INIT(4, auth_pap_init);