40 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $
41 */
42
43/*
44 * PPP node type.
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/time.h>
51#include <sys/mbuf.h>
52#include <sys/malloc.h>
53#include <sys/errno.h>
54#include <sys/ctype.h>
55
56#include <machine/limits.h>
57
58#include <netgraph/ng_message.h>
59#include <netgraph/netgraph.h>
60#include <netgraph/ng_parse.h>
61#include <netgraph/ng_ppp.h>
62#include <netgraph/ng_vjc.h>
63
64#define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
65#define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
66
67/* Some PPP protocol numbers we're interested in */
68#define PROT_APPLETALK 0x0029
69#define PROT_COMPD 0x00fd
70#define PROT_CRYPTD 0x0053
71#define PROT_IP 0x0021
72#define PROT_IPV6 0x0057
73#define PROT_IPX 0x002b
74#define PROT_LCP 0xc021
75#define PROT_MP 0x003d
76#define PROT_VJCOMP 0x002d
77#define PROT_VJUNCOMP 0x002f
78
79/* Multilink PPP definitions */
80#define MP_MIN_MRRU 1500 /* per RFC 1990 */
81#define MP_INITIAL_SEQ 0 /* per RFC 1990 */
82#define MP_MIN_LINK_MRU 32
83
84#define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
85#define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
86#define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
87#define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
88
89#define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
90#define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
91#define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
92#define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
93
94#define MP_NOSEQ 0x7fffffff /* impossible sequence number */
95
96/* Sign extension of MP sequence numbers */
97#define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
98 ((s) | ~MP_SHORT_SEQ_MASK) \
99 : ((s) & MP_SHORT_SEQ_MASK))
100#define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
101 ((s) | ~MP_LONG_SEQ_MASK) \
102 : ((s) & MP_LONG_SEQ_MASK))
103
104/* Comparision of MP sequence numbers. Note: all sequence numbers
105 except priv->xseq are stored with the sign bit extended. */
106#define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y))
107#define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y))
108
109#define MP_RECV_SEQ_DIFF(priv,x,y) \
110 ((priv)->conf.recvShortSeq ? \
111 MP_SHORT_SEQ_DIFF((x), (y)) : \
112 MP_LONG_SEQ_DIFF((x), (y)))
113
114/* Increment receive sequence number */
115#define MP_NEXT_RECV_SEQ(priv,seq) \
116 (((seq) + 1) & ((priv)->conf.recvShortSeq ? \
117 MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK))
118
119/* Don't fragment transmitted packets smaller than this */
120#define MP_MIN_FRAG_LEN 6
121
122/* Maximum fragment reasssembly queue length */
123#define MP_MAX_QUEUE_LEN 128
124
125/* Fragment queue scanner period */
126#define MP_FRAGTIMER_INTERVAL (hz/2)
127
128/* We store incoming fragments this way */
129struct ng_ppp_frag {
130 int seq; /* fragment seq# */
131 u_char first; /* First in packet? */
132 u_char last; /* Last in packet? */
133 struct timeval timestamp; /* time of reception */
134 struct mbuf *data; /* Fragment data */
135 meta_p meta; /* Fragment meta */
136 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
137};
138
139/* We use integer indicies to refer to the non-link hooks */
140static const char *const ng_ppp_hook_names[] = {
141 NG_PPP_HOOK_ATALK,
142#define HOOK_INDEX_ATALK 0
143 NG_PPP_HOOK_BYPASS,
144#define HOOK_INDEX_BYPASS 1
145 NG_PPP_HOOK_COMPRESS,
146#define HOOK_INDEX_COMPRESS 2
147 NG_PPP_HOOK_ENCRYPT,
148#define HOOK_INDEX_ENCRYPT 3
149 NG_PPP_HOOK_DECOMPRESS,
150#define HOOK_INDEX_DECOMPRESS 4
151 NG_PPP_HOOK_DECRYPT,
152#define HOOK_INDEX_DECRYPT 5
153 NG_PPP_HOOK_INET,
154#define HOOK_INDEX_INET 6
155 NG_PPP_HOOK_IPX,
156#define HOOK_INDEX_IPX 7
157 NG_PPP_HOOK_VJC_COMP,
158#define HOOK_INDEX_VJC_COMP 8
159 NG_PPP_HOOK_VJC_IP,
160#define HOOK_INDEX_VJC_IP 9
161 NG_PPP_HOOK_VJC_UNCOMP,
162#define HOOK_INDEX_VJC_UNCOMP 10
163 NG_PPP_HOOK_VJC_VJIP,
164#define HOOK_INDEX_VJC_VJIP 11
165 NG_PPP_HOOK_IPV6,
166#define HOOK_INDEX_IPV6 12
167 NULL
168#define HOOK_INDEX_MAX 13
169};
170
171/* We store index numbers in the hook private pointer. The HOOK_INDEX()
172 for a hook is either the index (above) for normal hooks, or the ones
173 complement of the link number for link hooks. */
174#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
175
176/* Per-link private information */
177struct ng_ppp_link {
178 struct ng_ppp_link_conf conf; /* link configuration */
179 hook_p hook; /* connection to link data */
180 int32_t seq; /* highest rec'd seq# - MSEQ */
181 struct timeval lastWrite; /* time of last write */
182 int bytesInQueue; /* bytes in the output queue */
183 struct ng_ppp_link_stat stats; /* Link stats */
184};
185
186/* Total per-node private information */
187struct ng_ppp_private {
188 struct ng_ppp_bund_conf conf; /* bundle config */
189 struct ng_ppp_link_stat bundleStats; /* bundle stats */
190 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
191 int32_t xseq; /* next out MP seq # */
192 int32_t mseq; /* min links[i].seq */
193 u_char vjCompHooked; /* VJ comp hooked up? */
194 u_char allLinksEqual; /* all xmit the same? */
195 u_char timerActive; /* frag timer active? */
196 u_int numActiveLinks; /* how many links up */
197 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
198 u_int lastLink; /* for round robin */
199 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
200 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
201 frags;
202 int qlen; /* fraq queue length */
203 struct callout_handle fragTimer; /* fraq queue check */
204};
205typedef struct ng_ppp_private *priv_p;
206
207/* Netgraph node methods */
208static ng_constructor_t ng_ppp_constructor;
209static ng_rcvmsg_t ng_ppp_rcvmsg;
210static ng_shutdown_t ng_ppp_rmnode;
211static ng_newhook_t ng_ppp_newhook;
212static ng_rcvdata_t ng_ppp_rcvdata;
213static ng_disconnect_t ng_ppp_disconnect;
214
215/* Helper functions */
216static int ng_ppp_input(node_p node, int bypass,
217 int linkNum, struct mbuf *m, meta_p meta);
218static int ng_ppp_output(node_p node, int bypass, int proto,
219 int linkNum, struct mbuf *m, meta_p meta);
220static int ng_ppp_mp_input(node_p node, int linkNum,
221 struct mbuf *m, meta_p meta);
222static int ng_ppp_check_packet(node_p node);
223static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
224static int ng_ppp_frag_process(node_p node);
225static int ng_ppp_frag_trim(node_p node);
226static void ng_ppp_frag_timeout(void *arg);
227static void ng_ppp_frag_checkstale(node_p node);
228static void ng_ppp_frag_reset(node_p node);
229static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
230static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
231static int ng_ppp_intcmp(const void *v1, const void *v2);
232static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
233static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
234static int ng_ppp_config_valid(node_p node,
235 const struct ng_ppp_node_conf *newConf);
236static void ng_ppp_update(node_p node, int newConf);
237static void ng_ppp_start_frag_timer(node_p node);
238static void ng_ppp_stop_frag_timer(node_p node);
239
240/* Parse type for struct ng_ppp_mp_state_type */
241static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = {
242 &ng_parse_hint32_type,
243 NG_PPP_MAX_LINKS
244};
245static const struct ng_parse_type ng_ppp_rseq_array_type = {
246 &ng_parse_fixedarray_type,
247 &ng_ppp_rseq_array_info,
248};
249static const struct ng_parse_struct_info ng_ppp_mp_state_type_info
250 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type);
251static const struct ng_parse_type ng_ppp_mp_state_type = {
252 &ng_parse_struct_type,
253 &ng_ppp_mp_state_type_info,
254};
255
256/* Parse type for struct ng_ppp_link_conf */
257static const struct ng_parse_struct_info
258 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO;
259static const struct ng_parse_type ng_ppp_link_type = {
260 &ng_parse_struct_type,
261 &ng_ppp_link_type_info,
262};
263
264/* Parse type for struct ng_ppp_bund_conf */
265static const struct ng_parse_struct_info
266 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO;
267static const struct ng_parse_type ng_ppp_bund_type = {
268 &ng_parse_struct_type,
269 &ng_ppp_bund_type_info,
270};
271
272/* Parse type for struct ng_ppp_node_conf */
273static const struct ng_parse_fixedarray_info ng_ppp_array_info = {
274 &ng_ppp_link_type,
275 NG_PPP_MAX_LINKS
276};
277static const struct ng_parse_type ng_ppp_link_array_type = {
278 &ng_parse_fixedarray_type,
279 &ng_ppp_array_info,
280};
281static const struct ng_parse_struct_info ng_ppp_conf_type_info
282 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
283static const struct ng_parse_type ng_ppp_conf_type = {
284 &ng_parse_struct_type,
285 &ng_ppp_conf_type_info
286};
287
288/* Parse type for struct ng_ppp_link_stat */
289static const struct ng_parse_struct_info
290 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO;
291static const struct ng_parse_type ng_ppp_stats_type = {
292 &ng_parse_struct_type,
293 &ng_ppp_stats_type_info
294};
295
296/* List of commands and how to convert arguments to/from ASCII */
297static const struct ng_cmdlist ng_ppp_cmds[] = {
298 {
299 NGM_PPP_COOKIE,
300 NGM_PPP_SET_CONFIG,
301 "setconfig",
302 &ng_ppp_conf_type,
303 NULL
304 },
305 {
306 NGM_PPP_COOKIE,
307 NGM_PPP_GET_CONFIG,
308 "getconfig",
309 NULL,
310 &ng_ppp_conf_type
311 },
312 {
313 NGM_PPP_COOKIE,
314 NGM_PPP_GET_MP_STATE,
315 "getmpstate",
316 NULL,
317 &ng_ppp_mp_state_type
318 },
319 {
320 NGM_PPP_COOKIE,
321 NGM_PPP_GET_LINK_STATS,
322 "getstats",
323 &ng_parse_int16_type,
324 &ng_ppp_stats_type
325 },
326 {
327 NGM_PPP_COOKIE,
328 NGM_PPP_CLR_LINK_STATS,
329 "clrstats",
330 &ng_parse_int16_type,
331 NULL
332 },
333 {
334 NGM_PPP_COOKIE,
335 NGM_PPP_GETCLR_LINK_STATS,
336 "getclrstats",
337 &ng_parse_int16_type,
338 &ng_ppp_stats_type
339 },
340 { 0 }
341};
342
343/* Node type descriptor */
344static struct ng_type ng_ppp_typestruct = {
| 40 * $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $
41 */
42
43/*
44 * PPP node type.
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/time.h>
51#include <sys/mbuf.h>
52#include <sys/malloc.h>
53#include <sys/errno.h>
54#include <sys/ctype.h>
55
56#include <machine/limits.h>
57
58#include <netgraph/ng_message.h>
59#include <netgraph/netgraph.h>
60#include <netgraph/ng_parse.h>
61#include <netgraph/ng_ppp.h>
62#include <netgraph/ng_vjc.h>
63
64#define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
65#define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
66
67/* Some PPP protocol numbers we're interested in */
68#define PROT_APPLETALK 0x0029
69#define PROT_COMPD 0x00fd
70#define PROT_CRYPTD 0x0053
71#define PROT_IP 0x0021
72#define PROT_IPV6 0x0057
73#define PROT_IPX 0x002b
74#define PROT_LCP 0xc021
75#define PROT_MP 0x003d
76#define PROT_VJCOMP 0x002d
77#define PROT_VJUNCOMP 0x002f
78
79/* Multilink PPP definitions */
80#define MP_MIN_MRRU 1500 /* per RFC 1990 */
81#define MP_INITIAL_SEQ 0 /* per RFC 1990 */
82#define MP_MIN_LINK_MRU 32
83
84#define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
85#define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
86#define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
87#define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
88
89#define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
90#define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
91#define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
92#define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
93
94#define MP_NOSEQ 0x7fffffff /* impossible sequence number */
95
96/* Sign extension of MP sequence numbers */
97#define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
98 ((s) | ~MP_SHORT_SEQ_MASK) \
99 : ((s) & MP_SHORT_SEQ_MASK))
100#define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
101 ((s) | ~MP_LONG_SEQ_MASK) \
102 : ((s) & MP_LONG_SEQ_MASK))
103
104/* Comparision of MP sequence numbers. Note: all sequence numbers
105 except priv->xseq are stored with the sign bit extended. */
106#define MP_SHORT_SEQ_DIFF(x,y) MP_SHORT_EXTEND((x) - (y))
107#define MP_LONG_SEQ_DIFF(x,y) MP_LONG_EXTEND((x) - (y))
108
109#define MP_RECV_SEQ_DIFF(priv,x,y) \
110 ((priv)->conf.recvShortSeq ? \
111 MP_SHORT_SEQ_DIFF((x), (y)) : \
112 MP_LONG_SEQ_DIFF((x), (y)))
113
114/* Increment receive sequence number */
115#define MP_NEXT_RECV_SEQ(priv,seq) \
116 (((seq) + 1) & ((priv)->conf.recvShortSeq ? \
117 MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK))
118
119/* Don't fragment transmitted packets smaller than this */
120#define MP_MIN_FRAG_LEN 6
121
122/* Maximum fragment reasssembly queue length */
123#define MP_MAX_QUEUE_LEN 128
124
125/* Fragment queue scanner period */
126#define MP_FRAGTIMER_INTERVAL (hz/2)
127
128/* We store incoming fragments this way */
129struct ng_ppp_frag {
130 int seq; /* fragment seq# */
131 u_char first; /* First in packet? */
132 u_char last; /* Last in packet? */
133 struct timeval timestamp; /* time of reception */
134 struct mbuf *data; /* Fragment data */
135 meta_p meta; /* Fragment meta */
136 TAILQ_ENTRY(ng_ppp_frag) f_qent; /* Fragment queue */
137};
138
139/* We use integer indicies to refer to the non-link hooks */
140static const char *const ng_ppp_hook_names[] = {
141 NG_PPP_HOOK_ATALK,
142#define HOOK_INDEX_ATALK 0
143 NG_PPP_HOOK_BYPASS,
144#define HOOK_INDEX_BYPASS 1
145 NG_PPP_HOOK_COMPRESS,
146#define HOOK_INDEX_COMPRESS 2
147 NG_PPP_HOOK_ENCRYPT,
148#define HOOK_INDEX_ENCRYPT 3
149 NG_PPP_HOOK_DECOMPRESS,
150#define HOOK_INDEX_DECOMPRESS 4
151 NG_PPP_HOOK_DECRYPT,
152#define HOOK_INDEX_DECRYPT 5
153 NG_PPP_HOOK_INET,
154#define HOOK_INDEX_INET 6
155 NG_PPP_HOOK_IPX,
156#define HOOK_INDEX_IPX 7
157 NG_PPP_HOOK_VJC_COMP,
158#define HOOK_INDEX_VJC_COMP 8
159 NG_PPP_HOOK_VJC_IP,
160#define HOOK_INDEX_VJC_IP 9
161 NG_PPP_HOOK_VJC_UNCOMP,
162#define HOOK_INDEX_VJC_UNCOMP 10
163 NG_PPP_HOOK_VJC_VJIP,
164#define HOOK_INDEX_VJC_VJIP 11
165 NG_PPP_HOOK_IPV6,
166#define HOOK_INDEX_IPV6 12
167 NULL
168#define HOOK_INDEX_MAX 13
169};
170
171/* We store index numbers in the hook private pointer. The HOOK_INDEX()
172 for a hook is either the index (above) for normal hooks, or the ones
173 complement of the link number for link hooks. */
174#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
175
176/* Per-link private information */
177struct ng_ppp_link {
178 struct ng_ppp_link_conf conf; /* link configuration */
179 hook_p hook; /* connection to link data */
180 int32_t seq; /* highest rec'd seq# - MSEQ */
181 struct timeval lastWrite; /* time of last write */
182 int bytesInQueue; /* bytes in the output queue */
183 struct ng_ppp_link_stat stats; /* Link stats */
184};
185
186/* Total per-node private information */
187struct ng_ppp_private {
188 struct ng_ppp_bund_conf conf; /* bundle config */
189 struct ng_ppp_link_stat bundleStats; /* bundle stats */
190 struct ng_ppp_link links[NG_PPP_MAX_LINKS];/* per-link info */
191 int32_t xseq; /* next out MP seq # */
192 int32_t mseq; /* min links[i].seq */
193 u_char vjCompHooked; /* VJ comp hooked up? */
194 u_char allLinksEqual; /* all xmit the same? */
195 u_char timerActive; /* frag timer active? */
196 u_int numActiveLinks; /* how many links up */
197 int activeLinks[NG_PPP_MAX_LINKS]; /* indicies */
198 u_int lastLink; /* for round robin */
199 hook_p hooks[HOOK_INDEX_MAX]; /* non-link hooks */
200 TAILQ_HEAD(ng_ppp_fraglist, ng_ppp_frag) /* fragment queue */
201 frags;
202 int qlen; /* fraq queue length */
203 struct callout_handle fragTimer; /* fraq queue check */
204};
205typedef struct ng_ppp_private *priv_p;
206
207/* Netgraph node methods */
208static ng_constructor_t ng_ppp_constructor;
209static ng_rcvmsg_t ng_ppp_rcvmsg;
210static ng_shutdown_t ng_ppp_rmnode;
211static ng_newhook_t ng_ppp_newhook;
212static ng_rcvdata_t ng_ppp_rcvdata;
213static ng_disconnect_t ng_ppp_disconnect;
214
215/* Helper functions */
216static int ng_ppp_input(node_p node, int bypass,
217 int linkNum, struct mbuf *m, meta_p meta);
218static int ng_ppp_output(node_p node, int bypass, int proto,
219 int linkNum, struct mbuf *m, meta_p meta);
220static int ng_ppp_mp_input(node_p node, int linkNum,
221 struct mbuf *m, meta_p meta);
222static int ng_ppp_check_packet(node_p node);
223static void ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap);
224static int ng_ppp_frag_process(node_p node);
225static int ng_ppp_frag_trim(node_p node);
226static void ng_ppp_frag_timeout(void *arg);
227static void ng_ppp_frag_checkstale(node_p node);
228static void ng_ppp_frag_reset(node_p node);
229static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
230static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
231static int ng_ppp_intcmp(const void *v1, const void *v2);
232static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
233static struct mbuf *ng_ppp_prepend(struct mbuf *m, const void *buf, int len);
234static int ng_ppp_config_valid(node_p node,
235 const struct ng_ppp_node_conf *newConf);
236static void ng_ppp_update(node_p node, int newConf);
237static void ng_ppp_start_frag_timer(node_p node);
238static void ng_ppp_stop_frag_timer(node_p node);
239
240/* Parse type for struct ng_ppp_mp_state_type */
241static const struct ng_parse_fixedarray_info ng_ppp_rseq_array_info = {
242 &ng_parse_hint32_type,
243 NG_PPP_MAX_LINKS
244};
245static const struct ng_parse_type ng_ppp_rseq_array_type = {
246 &ng_parse_fixedarray_type,
247 &ng_ppp_rseq_array_info,
248};
249static const struct ng_parse_struct_info ng_ppp_mp_state_type_info
250 = NG_PPP_MP_STATE_TYPE_INFO(&ng_ppp_rseq_array_type);
251static const struct ng_parse_type ng_ppp_mp_state_type = {
252 &ng_parse_struct_type,
253 &ng_ppp_mp_state_type_info,
254};
255
256/* Parse type for struct ng_ppp_link_conf */
257static const struct ng_parse_struct_info
258 ng_ppp_link_type_info = NG_PPP_LINK_TYPE_INFO;
259static const struct ng_parse_type ng_ppp_link_type = {
260 &ng_parse_struct_type,
261 &ng_ppp_link_type_info,
262};
263
264/* Parse type for struct ng_ppp_bund_conf */
265static const struct ng_parse_struct_info
266 ng_ppp_bund_type_info = NG_PPP_BUND_TYPE_INFO;
267static const struct ng_parse_type ng_ppp_bund_type = {
268 &ng_parse_struct_type,
269 &ng_ppp_bund_type_info,
270};
271
272/* Parse type for struct ng_ppp_node_conf */
273static const struct ng_parse_fixedarray_info ng_ppp_array_info = {
274 &ng_ppp_link_type,
275 NG_PPP_MAX_LINKS
276};
277static const struct ng_parse_type ng_ppp_link_array_type = {
278 &ng_parse_fixedarray_type,
279 &ng_ppp_array_info,
280};
281static const struct ng_parse_struct_info ng_ppp_conf_type_info
282 = NG_PPP_CONFIG_TYPE_INFO(&ng_ppp_bund_type, &ng_ppp_link_array_type);
283static const struct ng_parse_type ng_ppp_conf_type = {
284 &ng_parse_struct_type,
285 &ng_ppp_conf_type_info
286};
287
288/* Parse type for struct ng_ppp_link_stat */
289static const struct ng_parse_struct_info
290 ng_ppp_stats_type_info = NG_PPP_STATS_TYPE_INFO;
291static const struct ng_parse_type ng_ppp_stats_type = {
292 &ng_parse_struct_type,
293 &ng_ppp_stats_type_info
294};
295
296/* List of commands and how to convert arguments to/from ASCII */
297static const struct ng_cmdlist ng_ppp_cmds[] = {
298 {
299 NGM_PPP_COOKIE,
300 NGM_PPP_SET_CONFIG,
301 "setconfig",
302 &ng_ppp_conf_type,
303 NULL
304 },
305 {
306 NGM_PPP_COOKIE,
307 NGM_PPP_GET_CONFIG,
308 "getconfig",
309 NULL,
310 &ng_ppp_conf_type
311 },
312 {
313 NGM_PPP_COOKIE,
314 NGM_PPP_GET_MP_STATE,
315 "getmpstate",
316 NULL,
317 &ng_ppp_mp_state_type
318 },
319 {
320 NGM_PPP_COOKIE,
321 NGM_PPP_GET_LINK_STATS,
322 "getstats",
323 &ng_parse_int16_type,
324 &ng_ppp_stats_type
325 },
326 {
327 NGM_PPP_COOKIE,
328 NGM_PPP_CLR_LINK_STATS,
329 "clrstats",
330 &ng_parse_int16_type,
331 NULL
332 },
333 {
334 NGM_PPP_COOKIE,
335 NGM_PPP_GETCLR_LINK_STATS,
336 "getclrstats",
337 &ng_parse_int16_type,
338 &ng_ppp_stats_type
339 },
340 { 0 }
341};
342
343/* Node type descriptor */
344static struct ng_type ng_ppp_typestruct = {
|
346 NG_PPP_NODE_TYPE,
347 NULL,
348 ng_ppp_constructor,
349 ng_ppp_rcvmsg,
350 ng_ppp_rmnode,
351 ng_ppp_newhook,
352 NULL,
353 NULL,
354 ng_ppp_rcvdata,
355 ng_ppp_disconnect,
356 ng_ppp_cmds
357};
358NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
359
360static int *compareLatencies; /* hack for ng_ppp_intcmp() */
361
362/* Address and control field header */
363static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
364
365/* Maximum time we'll let a complete incoming packet sit in the queue */
366static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
367
368#define ERROUT(x) do { error = (x); goto done; } while (0)
369
370/************************************************************************
371 NETGRAPH NODE STUFF
372 ************************************************************************/
373
374/*
375 * Node type constructor
376 */
377static int
378ng_ppp_constructor(node_p *nodep)
379{
380 priv_p priv;
381 int i, error;
382
383 /* Allocate private structure */
384 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
385 if (priv == NULL)
386 return (ENOMEM);
387
388 /* Call generic node constructor */
389 if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) {
390 FREE(priv, M_NETGRAPH);
391 return (error);
392 }
393 (*nodep)->private = priv;
394
395 /* Initialize state */
396 TAILQ_INIT(&priv->frags);
397 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
398 priv->links[i].seq = MP_NOSEQ;
399 callout_handle_init(&priv->fragTimer);
400
401 /* Done */
402 return (0);
403}
404
405/*
406 * Give our OK for a hook to be added
407 */
408static int
409ng_ppp_newhook(node_p node, hook_p hook, const char *name)
410{
411 const priv_p priv = node->private;
412 int linkNum = -1;
413 hook_p *hookPtr = NULL;
414 int hookIndex = -1;
415
416 /* Figure out which hook it is */
417 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
418 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
419 const char *cp;
420 char *eptr;
421
422 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
423 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
424 return (EINVAL);
425 linkNum = (int)strtoul(cp, &eptr, 10);
426 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
427 return (EINVAL);
428 hookPtr = &priv->links[linkNum].hook;
429 hookIndex = ~linkNum;
430 } else { /* must be a non-link hook */
431 int i;
432
433 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
434 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
435 hookPtr = &priv->hooks[i];
436 hookIndex = i;
437 break;
438 }
439 }
440 if (ng_ppp_hook_names[i] == NULL)
441 return (EINVAL); /* no such hook */
442 }
443
444 /* See if hook is already connected */
445 if (*hookPtr != NULL)
446 return (EISCONN);
447
448 /* Disallow more than one link unless multilink is enabled */
449 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
450 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
451 return (ENODEV);
452
453 /* OK */
454 *hookPtr = hook;
455 HOOK_INDEX(hook) = hookIndex;
456 ng_ppp_update(node, 0);
457 return (0);
458}
459
460/*
461 * Receive a control message
462 */
463static int
464ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg,
465 const char *raddr, struct ng_mesg **rptr, hook_p lasthook)
466{
467 const priv_p priv = node->private;
468 struct ng_mesg *resp = NULL;
469 int error = 0;
470
471 switch (msg->header.typecookie) {
472 case NGM_PPP_COOKIE:
473 switch (msg->header.cmd) {
474 case NGM_PPP_SET_CONFIG:
475 {
476 struct ng_ppp_node_conf *const conf =
477 (struct ng_ppp_node_conf *)msg->data;
478 int i;
479
480 /* Check for invalid or illegal config */
481 if (msg->header.arglen != sizeof(*conf))
482 ERROUT(EINVAL);
483 if (!ng_ppp_config_valid(node, conf))
484 ERROUT(EINVAL);
485
486 /* Copy config */
487 priv->conf = conf->bund;
488 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
489 priv->links[i].conf = conf->links[i];
490 ng_ppp_update(node, 1);
491 break;
492 }
493 case NGM_PPP_GET_CONFIG:
494 {
495 struct ng_ppp_node_conf *conf;
496 int i;
497
498 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
499 if (resp == NULL)
500 ERROUT(ENOMEM);
501 conf = (struct ng_ppp_node_conf *)resp->data;
502 conf->bund = priv->conf;
503 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
504 conf->links[i] = priv->links[i].conf;
505 break;
506 }
507 case NGM_PPP_GET_MP_STATE:
508 {
509 struct ng_ppp_mp_state *info;
510 int i;
511
512 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT);
513 if (resp == NULL)
514 ERROUT(ENOMEM);
515 info = (struct ng_ppp_mp_state *)resp->data;
516 bzero(info, sizeof(*info));
517 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
518 if (priv->links[i].seq != MP_NOSEQ)
519 info->rseq[i] = priv->links[i].seq;
520 }
521 info->mseq = priv->mseq;
522 info->xseq = priv->xseq;
523 break;
524 }
525 case NGM_PPP_GET_LINK_STATS:
526 case NGM_PPP_CLR_LINK_STATS:
527 case NGM_PPP_GETCLR_LINK_STATS:
528 {
529 struct ng_ppp_link_stat *stats;
530 u_int16_t linkNum;
531
532 if (msg->header.arglen != sizeof(u_int16_t))
533 ERROUT(EINVAL);
534 linkNum = *((u_int16_t *) msg->data);
535 if (linkNum >= NG_PPP_MAX_LINKS
536 && linkNum != NG_PPP_BUNDLE_LINKNUM)
537 ERROUT(EINVAL);
538 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ?
539 &priv->bundleStats : &priv->links[linkNum].stats;
540 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) {
541 NG_MKRESPONSE(resp, msg,
542 sizeof(struct ng_ppp_link_stat), M_NOWAIT);
543 if (resp == NULL)
544 ERROUT(ENOMEM);
545 bcopy(stats, resp->data, sizeof(*stats));
546 }
547 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS)
548 bzero(stats, sizeof(*stats));
549 break;
550 }
551 default:
552 error = EINVAL;
553 break;
554 }
555 break;
556 case NGM_VJC_COOKIE:
557 {
558 char path[NG_PATHLEN + 1];
559 node_p origNode;
560
561 if ((error = ng_path2node(node, raddr, &origNode, NULL)) != 0)
562 ERROUT(error);
563 snprintf(path, sizeof(path), "[%lx]:%s",
564 (long)node->ID, NG_PPP_HOOK_VJC_IP);
565 return ng_send_msg(origNode, msg, path, NULL, NULL, rptr);
566 }
567 default:
568 error = EINVAL;
569 break;
570 }
571 if (rptr)
572 *rptr = resp;
573 else if (resp)
574 FREE(resp, M_NETGRAPH);
575
576done:
577 FREE(msg, M_NETGRAPH);
578 return (error);
579}
580
581/*
582 * Receive data on a hook
583 */
584static int
585ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
586 struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
587{
588 const node_p node = hook->node;
589 const priv_p priv = node->private;
590 const int index = HOOK_INDEX(hook);
591 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
592 hook_p outHook = NULL;
593 int proto = 0, error;
594
595 /* Did it come from a link hook? */
596 if (index < 0) {
597 struct ng_ppp_link *link;
598
599 /* Convert index into a link number */
600 linkNum = (u_int16_t)~index;
601 KASSERT(linkNum < NG_PPP_MAX_LINKS,
602 ("%s: bogus index 0x%x", __FUNCTION__, index));
603 link = &priv->links[linkNum];
604
605 /* Stats */
606 link->stats.recvFrames++;
607 link->stats.recvOctets += m->m_pkthdr.len;
608
609 /* Strip address and control fields, if present */
610 if (m->m_pkthdr.len >= 2) {
611 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
612 NG_FREE_DATA(m, meta);
613 return (ENOBUFS);
614 }
615 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
616 m_adj(m, 2);
617 }
618
619 /* Dispatch incoming frame (if not enabled, to bypass) */
620 return ng_ppp_input(node,
621 !link->conf.enableLink, linkNum, m, meta);
622 }
623
624 /* Get protocol & check if data allowed from this hook */
625 switch (index) {
626
627 /* Outgoing data */
628 case HOOK_INDEX_ATALK:
629 if (!priv->conf.enableAtalk) {
630 NG_FREE_DATA(m, meta);
631 return (ENXIO);
632 }
633 proto = PROT_APPLETALK;
634 break;
635 case HOOK_INDEX_IPX:
636 if (!priv->conf.enableIPX) {
637 NG_FREE_DATA(m, meta);
638 return (ENXIO);
639 }
640 proto = PROT_IPX;
641 break;
642 case HOOK_INDEX_IPV6:
643 if (!priv->conf.enableIPv6) {
644 NG_FREE_DATA(m, meta);
645 return (ENXIO);
646 }
647 proto = PROT_IPV6;
648 break;
649 case HOOK_INDEX_INET:
650 case HOOK_INDEX_VJC_VJIP:
651 if (!priv->conf.enableIP) {
652 NG_FREE_DATA(m, meta);
653 return (ENXIO);
654 }
655 proto = PROT_IP;
656 break;
657 case HOOK_INDEX_VJC_COMP:
658 if (!priv->conf.enableVJCompression) {
659 NG_FREE_DATA(m, meta);
660 return (ENXIO);
661 }
662 proto = PROT_VJCOMP;
663 break;
664 case HOOK_INDEX_VJC_UNCOMP:
665 if (!priv->conf.enableVJCompression) {
666 NG_FREE_DATA(m, meta);
667 return (ENXIO);
668 }
669 proto = PROT_VJUNCOMP;
670 break;
671 case HOOK_INDEX_COMPRESS:
672 if (!priv->conf.enableCompression) {
673 NG_FREE_DATA(m, meta);
674 return (ENXIO);
675 }
676 proto = PROT_COMPD;
677 break;
678 case HOOK_INDEX_ENCRYPT:
679 if (!priv->conf.enableEncryption) {
680 NG_FREE_DATA(m, meta);
681 return (ENXIO);
682 }
683 proto = PROT_CRYPTD;
684 break;
685 case HOOK_INDEX_BYPASS:
686 if (m->m_pkthdr.len < 4) {
687 NG_FREE_DATA(m, meta);
688 return (EINVAL);
689 }
690 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
691 NG_FREE_META(meta);
692 return (ENOBUFS);
693 }
694 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
695 proto = ntohs(mtod(m, u_int16_t *)[1]);
696 m_adj(m, 4);
697 if (linkNum >= NG_PPP_MAX_LINKS
698 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
699 NG_FREE_DATA(m, meta);
700 return (EINVAL);
701 }
702 break;
703
704 /* Incoming data */
705 case HOOK_INDEX_VJC_IP:
706 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
707 NG_FREE_DATA(m, meta);
708 return (ENXIO);
709 }
710 break;
711 case HOOK_INDEX_DECOMPRESS:
712 if (!priv->conf.enableDecompression) {
713 NG_FREE_DATA(m, meta);
714 return (ENXIO);
715 }
716 break;
717 case HOOK_INDEX_DECRYPT:
718 if (!priv->conf.enableDecryption) {
719 NG_FREE_DATA(m, meta);
720 return (ENXIO);
721 }
722 break;
723 default:
724 panic("%s: bogus index 0x%x", __FUNCTION__, index);
725 }
726
727 /* Now figure out what to do with the frame */
728 switch (index) {
729
730 /* Outgoing data */
731 case HOOK_INDEX_INET:
732 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
733 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
734 break;
735 }
736 /* FALLTHROUGH */
737 case HOOK_INDEX_ATALK:
738 case HOOK_INDEX_IPV6:
739 case HOOK_INDEX_IPX:
740 case HOOK_INDEX_VJC_COMP:
741 case HOOK_INDEX_VJC_UNCOMP:
742 case HOOK_INDEX_VJC_VJIP:
743 if (priv->conf.enableCompression
744 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
745 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
746 NG_FREE_META(meta);
747 return (ENOBUFS);
748 }
749 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
750 break;
751 }
752 /* FALLTHROUGH */
753 case HOOK_INDEX_COMPRESS:
754 if (priv->conf.enableEncryption
755 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
756 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
757 NG_FREE_META(meta);
758 return (ENOBUFS);
759 }
760 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
761 break;
762 }
763 /* FALLTHROUGH */
764 case HOOK_INDEX_ENCRYPT:
765 return ng_ppp_output(node, 0,
766 proto, NG_PPP_BUNDLE_LINKNUM, m, meta);
767
768 case HOOK_INDEX_BYPASS:
769 return ng_ppp_output(node, 1, proto, linkNum, m, meta);
770
771 /* Incoming data */
772 case HOOK_INDEX_DECRYPT:
773 case HOOK_INDEX_DECOMPRESS:
774 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
775
776 case HOOK_INDEX_VJC_IP:
777 outHook = priv->hooks[HOOK_INDEX_INET];
778 break;
779 }
780
781 /* Send packet out hook */
782 NG_SEND_DATA_RET(error, outHook, m, meta, resp);
783 if (m != NULL || meta != NULL)
784 return ng_ppp_rcvdata(outHook, m, meta, NULL, NULL, resp);
785 return (error);
786}
787
788/*
789 * Destroy node
790 */
791static int
792ng_ppp_rmnode(node_p node)
793{
794 const priv_p priv = node->private;
795
796 /* Stop fragment queue timer */
797 ng_ppp_stop_frag_timer(node);
798
799 /* Take down netgraph node */
800 node->flags |= NG_INVALID;
801 ng_cutlinks(node);
802 ng_unname(node);
803 ng_ppp_frag_reset(node);
804 bzero(priv, sizeof(*priv));
805 FREE(priv, M_NETGRAPH);
806 node->private = NULL;
807 ng_unref(node); /* let the node escape */
808 return (0);
809}
810
811/*
812 * Hook disconnection
813 */
814static int
815ng_ppp_disconnect(hook_p hook)
816{
817 const node_p node = hook->node;
818 const priv_p priv = node->private;
819 const int index = HOOK_INDEX(hook);
820
821 /* Zero out hook pointer */
822 if (index < 0)
823 priv->links[~index].hook = NULL;
824 else
825 priv->hooks[index] = NULL;
826
827 /* Update derived info (or go away if no hooks left) */
828 if (node->numhooks > 0)
829 ng_ppp_update(node, 0);
830 else
831 ng_rmnode(node);
832 return (0);
833}
834
835/************************************************************************
836 HELPER STUFF
837 ************************************************************************/
838
839/*
840 * Handle an incoming frame. Extract the PPP protocol number
841 * and dispatch accordingly.
842 */
843static int
844ng_ppp_input(node_p node, int bypass, int linkNum, struct mbuf *m, meta_p meta)
845{
846 const priv_p priv = node->private;
847 hook_p outHook = NULL;
848 int proto, error;
849
850 /* Extract protocol number */
851 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
852 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
853 NG_FREE_META(meta);
854 return (ENOBUFS);
855 }
856 proto = (proto << 8) + *mtod(m, u_char *);
857 m_adj(m, 1);
858 }
859 if (!PROT_VALID(proto)) {
860 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
861 priv->bundleStats.badProtos++;
862 else
863 priv->links[linkNum].stats.badProtos++;
864 NG_FREE_DATA(m, meta);
865 return (EINVAL);
866 }
867
868 /* Bypass frame? */
869 if (bypass)
870 goto bypass;
871
872 /* Check protocol */
873 switch (proto) {
874 case PROT_COMPD:
875 if (priv->conf.enableDecompression)
876 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
877 break;
878 case PROT_CRYPTD:
879 if (priv->conf.enableDecryption)
880 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
881 break;
882 case PROT_VJCOMP:
883 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
884 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
885 break;
886 case PROT_VJUNCOMP:
887 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
888 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
889 break;
890 case PROT_MP:
891 if (priv->conf.enableMultilink
892 && linkNum != NG_PPP_BUNDLE_LINKNUM)
893 return ng_ppp_mp_input(node, linkNum, m, meta);
894 break;
895 case PROT_APPLETALK:
896 if (priv->conf.enableAtalk)
897 outHook = priv->hooks[HOOK_INDEX_ATALK];
898 break;
899 case PROT_IPX:
900 if (priv->conf.enableIPX)
901 outHook = priv->hooks[HOOK_INDEX_IPX];
902 break;
903 case PROT_IP:
904 if (priv->conf.enableIP)
905 outHook = priv->hooks[HOOK_INDEX_INET];
906 break;
907 case PROT_IPV6:
908 if (priv->conf.enableIPv6)
909 outHook = priv->hooks[HOOK_INDEX_IPV6];
910 break;
911 }
912
913bypass:
914 /* For unknown/inactive protocols, forward out the bypass hook */
915 if (outHook == NULL) {
916 u_int16_t hdr[2];
917
918 hdr[0] = htons(linkNum);
919 hdr[1] = htons((u_int16_t)proto);
920 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
921 NG_FREE_META(meta);
922 return (ENOBUFS);
923 }
924 outHook = priv->hooks[HOOK_INDEX_BYPASS];
925 }
926
927 /* Forward frame */
928 NG_SEND_DATA(error, outHook, m, meta);
929 return (error);
930}
931
932/*
933 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM
934 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
935 */
936static int
937ng_ppp_output(node_p node, int bypass,
938 int proto, int linkNum, struct mbuf *m, meta_p meta)
939{
940 const priv_p priv = node->private;
941 struct ng_ppp_link *link;
942 int len, error;
943
944 /* If not doing MP, map bundle virtual link to (the only) link */
945 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
946 linkNum = priv->activeLinks[0];
947
948 /* Get link pointer (optimization) */
949 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
950 &priv->links[linkNum] : NULL;
951
952 /* Check link status (if real) */
953 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
954 if (!bypass && !link->conf.enableLink) {
955 NG_FREE_DATA(m, meta);
956 return (ENXIO);
957 }
958 if (link->hook == NULL) {
959 NG_FREE_DATA(m, meta);
960 return (ENETDOWN);
961 }
962 }
963
964 /* Prepend protocol number, possibly compressed */
965 if ((m = ng_ppp_addproto(m, proto,
966 linkNum == NG_PPP_BUNDLE_LINKNUM
967 || link->conf.enableProtoComp)) == NULL) {
968 NG_FREE_META(meta);
969 return (ENOBUFS);
970 }
971
972 /* Special handling for the MP virtual link */
973 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
974 return ng_ppp_mp_output(node, m, meta);
975
976 /* Prepend address and control field (unless compressed) */
977 if (proto == PROT_LCP || !link->conf.enableACFComp) {
978 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
979 NG_FREE_META(meta);
980 return (ENOBUFS);
981 }
982 }
983
984 /* Deliver frame */
985 len = m->m_pkthdr.len;
986 NG_SEND_DATA(error, link->hook, m, meta);
987
988 /* Update stats and 'bytes in queue' counter */
989 if (error == 0) {
990 link->stats.xmitFrames++;
991 link->stats.xmitOctets += len;
992 link->bytesInQueue += len;
993 getmicrouptime(&link->lastWrite);
994 }
995 return error;
996}
997
998/*
999 * Handle an incoming multi-link fragment
1000 *
1001 * The fragment reassembly algorithm is somewhat complex. This is mainly
1002 * because we are required not to reorder the reconstructed packets, yet
1003 * fragments are only guaranteed to arrive in order on a per-link basis.
1004 * In other words, when we have a complete packet ready, but the previous
1005 * packet is still incomplete, we have to decide between delivering the
1006 * complete packet and throwing away the incomplete one, or waiting to
1007 * see if the remainder of the incomplete one arrives, at which time we
1008 * can deliver both packets, in order.
1009 *
1010 * This problem is exacerbated by "sequence number slew", which is when
1011 * the sequence numbers coming in from different links are far apart from
1012 * each other. In particular, certain unnamed equipment (*cough* Ascend)
1013 * has been seen to generate sequence number slew of up to 10 on an ISDN
1014 * 2B-channel MP link. There is nothing invalid about sequence number slew
1015 * but it makes the reasssembly process have to work harder.
1016 *
1017 * However, the peer is required to transmit fragments in order on each
1018 * link. That means if we define MSEQ as the minimum over all links of
1019 * the highest sequence number received on that link, then we can always
1020 * give up any hope of receiving a fragment with sequence number < MSEQ in
1021 * the future (all of this using 'wraparound' sequence number space).
1022 * Therefore we can always immediately throw away incomplete packets
1023 * missing fragments with sequence numbers < MSEQ.
1024 *
1025 * Here is an overview of our algorithm:
1026 *
1027 * o Received fragments are inserted into a queue, for which we
1028 * maintain these invariants between calls to this function:
1029 *
1030 * - Fragments are ordered in the queue by sequence number
1031 * - If a complete packet is at the head of the queue, then
1032 * the first fragment in the packet has seq# > MSEQ + 1
1033 * (otherwise, we could deliver it immediately)
1034 * - If any fragments have seq# < MSEQ, then they are necessarily
1035 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
1036 * we can throw them away because they'll never be completed)
1037 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
1038 *
1039 * o We have a periodic timer that checks the queue for the first
1040 * complete packet that has been sitting in the queue "too long".
1041 * When one is detected, all previous (incomplete) fragments are
1042 * discarded, their missing fragments are declared lost and MSEQ
1043 * is increased.
1044 *
1045 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1046 * because we've already delcared it lost.
1047 *
1048 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1049 */
1050static int
1051ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
1052{
1053 const priv_p priv = node->private;
1054 struct ng_ppp_link *const link = &priv->links[linkNum];
1055 struct ng_ppp_frag frag0, *frag = &frag0;
1056 struct ng_ppp_frag *qent;
1057 int i, diff, inserted;
1058
1059 /* Stats */
1060 priv->bundleStats.recvFrames++;
1061 priv->bundleStats.recvOctets += m->m_pkthdr.len;
1062
1063 /* Extract fragment information from MP header */
1064 if (priv->conf.recvShortSeq) {
1065 u_int16_t shdr;
1066
1067 if (m->m_pkthdr.len < 2) {
1068 link->stats.runts++;
1069 NG_FREE_DATA(m, meta);
1070 return (EINVAL);
1071 }
1072 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1073 NG_FREE_META(meta);
1074 return (ENOBUFS);
1075 }
1076 shdr = ntohs(*mtod(m, u_int16_t *));
1077 frag->seq = MP_SHORT_EXTEND(shdr);
1078 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1079 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1080 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1081 m_adj(m, 2);
1082 } else {
1083 u_int32_t lhdr;
1084
1085 if (m->m_pkthdr.len < 4) {
1086 link->stats.runts++;
1087 NG_FREE_DATA(m, meta);
1088 return (EINVAL);
1089 }
1090 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1091 NG_FREE_META(meta);
1092 return (ENOBUFS);
1093 }
1094 lhdr = ntohl(*mtod(m, u_int32_t *));
1095 frag->seq = MP_LONG_EXTEND(lhdr);
1096 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1097 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1098 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1099 m_adj(m, 4);
1100 }
1101 frag->data = m;
1102 frag->meta = meta;
1103 getmicrouptime(&frag->timestamp);
1104
1105 /* If sequence number is < MSEQ, we've already declared this
1106 fragment as lost, so we have no choice now but to drop it */
1107 if (diff < 0) {
1108 link->stats.dropFragments++;
1109 NG_FREE_DATA(m, meta);
1110 return (0);
1111 }
1112
1113 /* Update highest received sequence number on this link and MSEQ */
1114 priv->mseq = link->seq = frag->seq;
1115 for (i = 0; i < priv->numActiveLinks; i++) {
1116 struct ng_ppp_link *const alink =
1117 &priv->links[priv->activeLinks[i]];
1118
1119 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1120 priv->mseq = alink->seq;
1121 }
1122
1123 /* Allocate a new frag struct for the queue */
1124 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT);
1125 if (frag == NULL) {
1126 NG_FREE_DATA(m, meta);
1127 ng_ppp_frag_process(node);
1128 return (ENOMEM);
1129 }
1130 *frag = frag0;
1131
1132 /* Add fragment to queue, which is sorted by sequence number */
1133 inserted = 0;
1134 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) {
1135 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq);
1136 if (diff > 0) {
1137 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1138 inserted = 1;
1139 break;
1140 } else if (diff == 0) { /* should never happen! */
1141 link->stats.dupFragments++;
1142 NG_FREE_DATA(frag->data, frag->meta);
1143 FREE(frag, M_NETGRAPH);
1144 return (EINVAL);
1145 }
1146 }
1147 if (!inserted)
1148 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1149 priv->qlen++;
1150
1151 /* Process the queue */
1152 return ng_ppp_frag_process(node);
1153}
1154
1155/*
1156 * Examine our list of fragments, and determine if there is a
1157 * complete and deliverable packet at the head of the list.
1158 * Return 1 if so, zero otherwise.
1159 */
1160static int
1161ng_ppp_check_packet(node_p node)
1162{
1163 const priv_p priv = node->private;
1164 struct ng_ppp_frag *qent, *qnext;
1165
1166 /* Check for empty queue */
1167 if (TAILQ_EMPTY(&priv->frags))
1168 return (0);
1169
1170 /* Check first fragment is the start of a deliverable packet */
1171 qent = TAILQ_FIRST(&priv->frags);
1172 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1173 return (0);
1174
1175 /* Check that all the fragments are there */
1176 while (!qent->last) {
1177 qnext = TAILQ_NEXT(qent, f_qent);
1178 if (qnext == NULL) /* end of queue */
1179 return (0);
1180 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq))
1181 return (0);
1182 qent = qnext;
1183 }
1184
1185 /* Got one */
1186 return (1);
1187}
1188
1189/*
1190 * Pull a completed packet off the head of the incoming fragment queue.
1191 * This assumes there is a completed packet there to pull off.
1192 */
1193static void
1194ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1195{
1196 const priv_p priv = node->private;
1197 struct ng_ppp_frag *qent, *qnext;
1198 struct mbuf *m = NULL, *tail;
1199
1200 qent = TAILQ_FIRST(&priv->frags);
1201 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first,
1202 ("%s: no packet", __FUNCTION__));
1203 for (tail = NULL; qent != NULL; qent = qnext) {
1204 qnext = TAILQ_NEXT(qent, f_qent);
1205 KASSERT(!TAILQ_EMPTY(&priv->frags),
1206 ("%s: empty q", __FUNCTION__));
1207 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1208 if (tail == NULL) {
1209 tail = m = qent->data;
1210 *metap = qent->meta; /* inherit first frag's meta */
1211 } else {
1212 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1213 tail->m_next = qent->data;
1214 NG_FREE_META(qent->meta); /* drop other frags' metas */
1215 }
1216 while (tail->m_next != NULL)
1217 tail = tail->m_next;
1218 if (qent->last)
1219 qnext = NULL;
1220 FREE(qent, M_NETGRAPH);
1221 priv->qlen--;
1222 }
1223 *mp = m;
1224}
1225
1226/*
1227 * Trim fragments from the queue whose packets can never be completed.
1228 * This assumes a complete packet is NOT at the beginning of the queue.
1229 * Returns 1 if fragments were removed, zero otherwise.
1230 */
1231static int
1232ng_ppp_frag_trim(node_p node)
1233{
1234 const priv_p priv = node->private;
1235 struct ng_ppp_frag *qent, *qnext = NULL;
1236 int removed = 0;
1237
1238 /* Scan for "dead" fragments and remove them */
1239 while (1) {
1240 int dead = 0;
1241
1242 /* If queue is empty, we're done */
1243 if (TAILQ_EMPTY(&priv->frags))
1244 break;
1245
1246 /* Determine whether first fragment can ever be completed */
1247 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1248 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1249 break;
1250 qnext = TAILQ_NEXT(qent, f_qent);
1251 KASSERT(qnext != NULL,
1252 ("%s: last frag < MSEQ?", __FUNCTION__));
1253 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)
1254 || qent->last || qnext->first) {
1255 dead = 1;
1256 break;
1257 }
1258 }
1259 if (!dead)
1260 break;
1261
1262 /* Remove fragment and all others in the same packet */
1263 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) {
1264 KASSERT(!TAILQ_EMPTY(&priv->frags),
1265 ("%s: empty q", __FUNCTION__));
1266 priv->bundleStats.dropFragments++;
1267 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1268 NG_FREE_DATA(qent->data, qent->meta);
1269 FREE(qent, M_NETGRAPH);
1270 priv->qlen--;
1271 removed = 1;
1272 }
1273 }
1274 return (removed);
1275}
1276
1277/*
1278 * Run the queue, restoring the queue invariants
1279 */
1280static int
1281ng_ppp_frag_process(node_p node)
1282{
1283 const priv_p priv = node->private;
1284 struct mbuf *m;
1285 meta_p meta;
1286
1287 /* Deliver any deliverable packets */
1288 while (ng_ppp_check_packet(node)) {
1289 ng_ppp_get_packet(node, &m, &meta);
1290 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1291 }
1292
1293 /* Delete dead fragments and try again */
1294 if (ng_ppp_frag_trim(node)) {
1295 while (ng_ppp_check_packet(node)) {
1296 ng_ppp_get_packet(node, &m, &meta);
1297 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1298 }
1299 }
1300
1301 /* Check for stale fragments while we're here */
1302 ng_ppp_frag_checkstale(node);
1303
1304 /* Check queue length */
1305 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1306 struct ng_ppp_frag *qent;
1307 int i;
1308
1309 /* Get oldest fragment */
1310 KASSERT(!TAILQ_EMPTY(&priv->frags),
1311 ("%s: empty q", __FUNCTION__));
1312 qent = TAILQ_FIRST(&priv->frags);
1313
1314 /* Bump MSEQ if necessary */
1315 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1316 priv->mseq = qent->seq;
1317 for (i = 0; i < priv->numActiveLinks; i++) {
1318 struct ng_ppp_link *const alink =
1319 &priv->links[priv->activeLinks[i]];
1320
1321 if (MP_RECV_SEQ_DIFF(priv,
1322 alink->seq, priv->mseq) < 0)
1323 alink->seq = priv->mseq;
1324 }
1325 }
1326
1327 /* Drop it */
1328 priv->bundleStats.dropFragments++;
1329 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1330 NG_FREE_DATA(qent->data, qent->meta);
1331 FREE(qent, M_NETGRAPH);
1332 priv->qlen--;
1333
1334 /* Process queue again */
1335 return ng_ppp_frag_process(node);
1336 }
1337
1338 /* Done */
1339 return (0);
1340}
1341
1342/*
1343 * Check for 'stale' completed packets that need to be delivered
1344 *
1345 * If a link goes down or has a temporary failure, MSEQ can get
1346 * "stuck", because no new incoming fragments appear on that link.
1347 * This can cause completed packets to never get delivered if
1348 * their sequence numbers are all > MSEQ + 1.
1349 *
1350 * This routine checks how long all of the completed packets have
1351 * been sitting in the queue, and if too long, removes fragments
1352 * from the queue and increments MSEQ to allow them to be delivered.
1353 */
1354static void
1355ng_ppp_frag_checkstale(node_p node)
1356{
1357 const priv_p priv = node->private;
1358 struct ng_ppp_frag *qent, *beg, *end;
1359 struct timeval now, age;
1360 struct mbuf *m;
1361 meta_p meta;
1362 int i, seq;
1363
1364 now.tv_sec = 0; /* uninitialized state */
1365 while (1) {
1366
1367 /* If queue is empty, we're done */
1368 if (TAILQ_EMPTY(&priv->frags))
1369 break;
1370
1371 /* Find the first complete packet in the queue */
1372 beg = end = NULL;
1373 seq = TAILQ_FIRST(&priv->frags)->seq;
1374 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1375 if (qent->first)
1376 beg = qent;
1377 else if (qent->seq != seq)
1378 beg = NULL;
1379 if (beg != NULL && qent->last) {
1380 end = qent;
1381 break;
1382 }
1383 seq = MP_NEXT_RECV_SEQ(priv, seq);
1384 }
1385
1386 /* If none found, exit */
1387 if (end == NULL)
1388 break;
1389
1390 /* Get current time (we assume we've been up for >= 1 second) */
1391 if (now.tv_sec == 0)
1392 getmicrouptime(&now);
1393
1394 /* Check if packet has been queued too long */
1395 age = now;
1396 timevalsub(&age, &beg->timestamp);
1397 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1398 break;
1399
1400 /* Throw away junk fragments in front of the completed packet */
1401 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) {
1402 KASSERT(!TAILQ_EMPTY(&priv->frags),
1403 ("%s: empty q", __FUNCTION__));
1404 priv->bundleStats.dropFragments++;
1405 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1406 NG_FREE_DATA(qent->data, qent->meta);
1407 FREE(qent, M_NETGRAPH);
1408 priv->qlen--;
1409 }
1410
1411 /* Extract completed packet */
1412 ng_ppp_get_packet(node, &m, &meta);
1413
1414 /* Bump MSEQ if necessary */
1415 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) {
1416 priv->mseq = end->seq;
1417 for (i = 0; i < priv->numActiveLinks; i++) {
1418 struct ng_ppp_link *const alink =
1419 &priv->links[priv->activeLinks[i]];
1420
1421 if (MP_RECV_SEQ_DIFF(priv,
1422 alink->seq, priv->mseq) < 0)
1423 alink->seq = priv->mseq;
1424 }
1425 }
1426
1427 /* Deliver packet */
1428 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1429 }
1430}
1431
1432/*
1433 * Periodically call ng_ppp_frag_checkstale()
1434 */
1435static void
1436ng_ppp_frag_timeout(void *arg)
1437{
1438 const node_p node = arg;
1439 const priv_p priv = node->private;
1440 int s = splnet();
1441
1442 /* Handle the race where shutdown happens just before splnet() above */
1443 if ((node->flags & NG_INVALID) != 0) {
1444 ng_unref(node);
1445 splx(s);
1446 return;
1447 }
1448
1449 /* Reset timer state after timeout */
1450 KASSERT(priv->timerActive, ("%s: !timerActive", __FUNCTION__));
1451 priv->timerActive = 0;
1452 KASSERT(node->refs > 1, ("%s: refs=%d", __FUNCTION__, node->refs));
1453 ng_unref(node);
1454
1455 /* Start timer again */
1456 ng_ppp_start_frag_timer(node);
1457
1458 /* Scan the fragment queue */
1459 ng_ppp_frag_checkstale(node);
1460 splx(s);
1461}
1462
1463/*
1464 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1465 * the frame across the individual PPP links and do so.
1466 */
1467static int
1468ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1469{
1470 const priv_p priv = node->private;
1471 int distrib[NG_PPP_MAX_LINKS];
1472 int firstFragment;
1473 int activeLinkNum;
1474
1475 /* At least one link must be active */
1476 if (priv->numActiveLinks == 0) {
1477 NG_FREE_DATA(m, meta);
1478 return (ENETDOWN);
1479 }
1480
1481 /* Round-robin strategy */
1482 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1483 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1484 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1485 distrib[activeLinkNum] = m->m_pkthdr.len;
1486 goto deliver;
1487 }
1488
1489 /* Strategy when all links are equivalent (optimize the common case) */
1490 if (priv->allLinksEqual) {
1491 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1492 int i, remain;
1493
1494 for (i = 0; i < priv->numActiveLinks; i++)
1495 distrib[priv->lastLink++ % priv->numActiveLinks]
1496 = fraction;
1497 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1498 while (remain > 0) {
1499 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1500 remain--;
1501 }
1502 goto deliver;
1503 }
1504
1505 /* Strategy when all links are not equivalent */
1506 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1507
1508deliver:
1509 /* Update stats */
1510 priv->bundleStats.xmitFrames++;
1511 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1512
1513 /* Send alloted portions of frame out on the link(s) */
1514 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1515 activeLinkNum >= 0; activeLinkNum--) {
1516 const int linkNum = priv->activeLinks[activeLinkNum];
1517 struct ng_ppp_link *const link = &priv->links[linkNum];
1518
1519 /* Deliver fragment(s) out the next link */
1520 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1521 int len, lastFragment, error;
1522 struct mbuf *m2;
1523 meta_p meta2;
1524
1525 /* Calculate fragment length; don't exceed link MTU */
1526 len = distrib[activeLinkNum];
1527 if (len > link->conf.mru)
1528 len = link->conf.mru;
1529 distrib[activeLinkNum] -= len;
1530 lastFragment = (len == m->m_pkthdr.len);
1531
1532 /* Split off next fragment as "m2" */
1533 m2 = m;
1534 if (!lastFragment) {
1535 struct mbuf *n = m_split(m, len, M_NOWAIT);
1536
1537 if (n == NULL) {
1538 NG_FREE_DATA(m, meta);
1539 return (ENOMEM);
1540 }
1541 m = n;
1542 }
1543
1544 /* Prepend MP header */
1545 if (priv->conf.xmitShortSeq) {
1546 u_int16_t shdr;
1547
1548 shdr = priv->xseq;
1549 priv->xseq =
1550 (priv->xseq + 1) & MP_SHORT_SEQ_MASK;
1551 if (firstFragment)
1552 shdr |= MP_SHORT_FIRST_FLAG;
1553 if (lastFragment)
1554 shdr |= MP_SHORT_LAST_FLAG;
1555 shdr = htons(shdr);
1556 m2 = ng_ppp_prepend(m2, &shdr, 2);
1557 } else {
1558 u_int32_t lhdr;
1559
1560 lhdr = priv->xseq;
1561 priv->xseq =
1562 (priv->xseq + 1) & MP_LONG_SEQ_MASK;
1563 if (firstFragment)
1564 lhdr |= MP_LONG_FIRST_FLAG;
1565 if (lastFragment)
1566 lhdr |= MP_LONG_LAST_FLAG;
1567 lhdr = htonl(lhdr);
1568 m2 = ng_ppp_prepend(m2, &lhdr, 4);
1569 }
1570 if (m2 == NULL) {
1571 if (!lastFragment)
1572 m_freem(m);
1573 NG_FREE_META(meta);
1574 return (ENOBUFS);
1575 }
1576
1577 /* Copy the meta information, if any */
1578 meta2 = lastFragment ? meta : ng_copy_meta(meta);
1579
1580 /* Send fragment */
1581 error = ng_ppp_output(node, 0,
1582 PROT_MP, linkNum, m2, meta2);
1583 if (error != 0) {
1584 if (!lastFragment)
1585 NG_FREE_DATA(m, meta);
1586 return (error);
1587 }
1588 }
1589 }
1590
1591 /* Done */
1592 return (0);
1593}
1594
1595/*
1596 * Computing the optimal fragmentation
1597 * -----------------------------------
1598 *
1599 * This routine tries to compute the optimal fragmentation pattern based
1600 * on each link's latency, bandwidth, and calculated additional latency.
1601 * The latter quantity is the additional latency caused by previously
1602 * written data that has not been transmitted yet.
1603 *
1604 * This algorithm is only useful when not all of the links have the
1605 * same latency and bandwidth values.
1606 *
1607 * The essential idea is to make the last bit of each fragment of the
1608 * frame arrive at the opposite end at the exact same time. This greedy
1609 * algorithm is optimal, in that no other scheduling could result in any
1610 * packet arriving any sooner unless packets are delivered out of order.
1611 *
1612 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and
1613 * latency l_i (in miliseconds). Consider the function function f_i(t)
1614 * which is equal to the number of bytes that will have arrived at
1615 * the peer after t miliseconds if we start writing continuously at
1616 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i).
1617 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i).
1618 * Note that the y-intersect is always <= zero because latency can't be
1619 * negative. Note also that really the function is f_i(t) except when
1620 * f_i(t) is negative, in which case the function is zero. To take
1621 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }.
1622 * So the actual number of bytes that will have arrived at the peer after
1623 * t miliseconds is f_i(t) * Q_i(t).
1624 *
1625 * At any given time, each link has some additional latency a_i >= 0
1626 * due to previously written fragment(s) which are still in the queue.
1627 * This value is easily computed from the time since last transmission,
1628 * the previous latency value, the number of bytes written, and the
1629 * link's bandwidth.
1630 *
1631 * Assume that l_i includes any a_i already, and that the links are
1632 * sorted by latency, so that l_i <= l_{i+1}.
1633 *
1634 * Let N be the total number of bytes in the current frame we are sending.
1635 *
1636 * Suppose we were to start writing bytes at time t = 0 on all links
1637 * simultaneously, which is the most we can possibly do. Then let
1638 * F(t) be equal to the total number of bytes received by the peer
1639 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)).
1640 *
1641 * Our goal is simply this: fragment the frame across the links such
1642 * that the peer is able to reconstruct the completed frame as soon as
1643 * possible, i.e., at the least possible value of t. Call this value t_0.
1644 *
1645 * Then it follows that F(t_0) = N. Our strategy is first to find the value
1646 * of t_0, and then deduce how many bytes to write to each link.
1647 *
1648 * Rewriting F(t_0):
1649 *
1650 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) )
1651 *
1652 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will
1653 * lie in one of these ranges. To find it, we just need to find the i such
1654 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values
1655 * for Q_i() in this range, plug in the remaining values, solving for t_0.
1656 *
1657 * Once t_0 is known, then the number of bytes to send on link i is
1658 * just f_i(t_0) * Q_i(t_0).
1659 *
1660 * In other words, we start allocating bytes to the links one at a time.
1661 * We keep adding links until the frame is completely sent. Some links
1662 * may not get any bytes because their latency is too high.
1663 *
1664 * Is all this work really worth the trouble? Depends on the situation.
1665 * The bigger the ratio of computer speed to link speed, and the more
1666 * important total bundle latency is (e.g., for interactive response time),
1667 * the more it's worth it. There is however the cost of calling this
1668 * function for every frame. The running time is O(n^2) where n is the
1669 * number of links that receive a non-zero number of bytes.
1670 *
1671 * Since latency is measured in miliseconds, the "resolution" of this
1672 * algorithm is one milisecond.
1673 *
1674 * To avoid this algorithm altogether, configure all links to have the
1675 * same latency and bandwidth.
1676 */
1677static void
1678ng_ppp_mp_strategy(node_p node, int len, int *distrib)
1679{
1680 const priv_p priv = node->private;
1681 int latency[NG_PPP_MAX_LINKS];
1682 int sortByLatency[NG_PPP_MAX_LINKS];
1683 int activeLinkNum;
1684 int t0, total, topSum, botSum;
1685 struct timeval now;
1686 int i, numFragments;
1687
1688 /* If only one link, this gets real easy */
1689 if (priv->numActiveLinks == 1) {
1690 distrib[0] = len;
1691 return;
1692 }
1693
1694 /* Get current time */
1695 getmicrouptime(&now);
1696
1697 /* Compute latencies for each link at this point in time */
1698 for (activeLinkNum = 0;
1699 activeLinkNum < priv->numActiveLinks; activeLinkNum++) {
1700 struct ng_ppp_link *alink;
1701 struct timeval diff;
1702 int xmitBytes;
1703
1704 /* Start with base latency value */
1705 alink = &priv->links[priv->activeLinks[activeLinkNum]];
1706 latency[activeLinkNum] = alink->conf.latency;
1707 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */
1708
1709 /* Any additional latency? */
1710 if (alink->bytesInQueue == 0)
1711 continue;
1712
1713 /* Compute time delta since last write */
1714 diff = now;
1715 timevalsub(&diff, &alink->lastWrite);
1716 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */
1717 alink->bytesInQueue = 0;
1718 continue;
1719 }
1720
1721 /* How many bytes could have transmitted since last write? */
1722 xmitBytes = (alink->conf.bandwidth * diff.tv_sec)
1723 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100;
1724 alink->bytesInQueue -= xmitBytes;
1725 if (alink->bytesInQueue < 0)
1726 alink->bytesInQueue = 0;
1727 else
1728 latency[activeLinkNum] +=
1729 (100 * alink->bytesInQueue) / alink->conf.bandwidth;
1730 }
1731
1732 /* Sort active links by latency */
1733 compareLatencies = latency;
1734 qsort(sortByLatency,
1735 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp);
1736 compareLatencies = NULL;
1737
1738 /* Find the interval we need (add links in sortByLatency[] order) */
1739 for (numFragments = 1;
1740 numFragments < priv->numActiveLinks; numFragments++) {
1741 for (total = i = 0; i < numFragments; i++) {
1742 int flowTime;
1743
1744 flowTime = latency[sortByLatency[numFragments]]
1745 - latency[sortByLatency[i]];
1746 total += ((flowTime * priv->links[
1747 priv->activeLinks[sortByLatency[i]]].conf.bandwidth)
1748 + 99) / 100;
1749 }
1750 if (total >= len)
1751 break;
1752 }
1753
1754 /* Solve for t_0 in that interval */
1755 for (topSum = botSum = i = 0; i < numFragments; i++) {
1756 int bw = priv->links[
1757 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1758
1759 topSum += latency[sortByLatency[i]] * bw; /* / 100 */
1760 botSum += bw; /* / 100 */
1761 }
1762 t0 = ((len * 100) + topSum + botSum / 2) / botSum;
1763
1764 /* Compute f_i(t_0) all i */
1765 bzero(distrib, priv->numActiveLinks * sizeof(*distrib));
1766 for (total = i = 0; i < numFragments; i++) {
1767 int bw = priv->links[
1768 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1769
1770 distrib[sortByLatency[i]] =
1771 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100;
1772 total += distrib[sortByLatency[i]];
1773 }
1774
1775 /* Deal with any rounding error */
1776 if (total < len) {
1777 struct ng_ppp_link *fastLink =
1778 &priv->links[priv->activeLinks[sortByLatency[0]]];
1779 int fast = 0;
1780
1781 /* Find the fastest link */
1782 for (i = 1; i < numFragments; i++) {
1783 struct ng_ppp_link *const link =
1784 &priv->links[priv->activeLinks[sortByLatency[i]]];
1785
1786 if (link->conf.bandwidth > fastLink->conf.bandwidth) {
1787 fast = i;
1788 fastLink = link;
1789 }
1790 }
1791 distrib[sortByLatency[fast]] += len - total;
1792 } else while (total > len) {
1793 struct ng_ppp_link *slowLink =
1794 &priv->links[priv->activeLinks[sortByLatency[0]]];
1795 int delta, slow = 0;
1796
1797 /* Find the slowest link that still has bytes to remove */
1798 for (i = 1; i < numFragments; i++) {
1799 struct ng_ppp_link *const link =
1800 &priv->links[priv->activeLinks[sortByLatency[i]]];
1801
1802 if (distrib[sortByLatency[slow]] == 0
1803 || (distrib[sortByLatency[i]] > 0
1804 && link->conf.bandwidth <
1805 slowLink->conf.bandwidth)) {
1806 slow = i;
1807 slowLink = link;
1808 }
1809 }
1810 delta = total - len;
1811 if (delta > distrib[sortByLatency[slow]])
1812 delta = distrib[sortByLatency[slow]];
1813 distrib[sortByLatency[slow]] -= delta;
1814 total -= delta;
1815 }
1816}
1817
1818/*
1819 * Compare two integers
1820 */
1821static int
1822ng_ppp_intcmp(const void *v1, const void *v2)
1823{
1824 const int index1 = *((const int *) v1);
1825 const int index2 = *((const int *) v2);
1826
1827 return compareLatencies[index1] - compareLatencies[index2];
1828}
1829
1830/*
1831 * Prepend a possibly compressed PPP protocol number in front of a frame
1832 */
1833static struct mbuf *
1834ng_ppp_addproto(struct mbuf *m, int proto, int compOK)
1835{
1836 if (compOK && PROT_COMPRESSABLE(proto)) {
1837 u_char pbyte = (u_char)proto;
1838
1839 return ng_ppp_prepend(m, &pbyte, 1);
1840 } else {
1841 u_int16_t pword = htons((u_int16_t)proto);
1842
1843 return ng_ppp_prepend(m, &pword, 2);
1844 }
1845}
1846
1847/*
1848 * Prepend some bytes to an mbuf
1849 */
1850static struct mbuf *
1851ng_ppp_prepend(struct mbuf *m, const void *buf, int len)
1852{
1853 M_PREPEND(m, len, M_NOWAIT);
1854 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL))
1855 return (NULL);
1856 bcopy(buf, mtod(m, u_char *), len);
1857 return (m);
1858}
1859
1860/*
1861 * Update private information that is derived from other private information
1862 */
1863static void
1864ng_ppp_update(node_p node, int newConf)
1865{
1866 const priv_p priv = node->private;
1867 int i;
1868
1869 /* Update active status for VJ Compression */
1870 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL
1871 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL
1872 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL
1873 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL;
1874
1875 /* Increase latency for each link an amount equal to one MP header */
1876 if (newConf) {
1877 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1878 int hdrBytes;
1879
1880 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2)
1881 + (priv->links[i].conf.enableProtoComp ? 1 : 2)
1882 + (priv->conf.xmitShortSeq ? 2 : 4);
1883 priv->links[i].conf.latency +=
1884 ((hdrBytes * priv->links[i].conf.bandwidth) + 50)
1885 / 100;
1886 }
1887 }
1888
1889 /* Update list of active links */
1890 bzero(&priv->activeLinks, sizeof(priv->activeLinks));
1891 priv->numActiveLinks = 0;
1892 priv->allLinksEqual = 1;
1893 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1894 struct ng_ppp_link *const link = &priv->links[i];
1895
1896 /* Is link active? */
1897 if (link->conf.enableLink && link->hook != NULL) {
1898 struct ng_ppp_link *link0;
1899
1900 /* Add link to list of active links */
1901 priv->activeLinks[priv->numActiveLinks++] = i;
1902 link0 = &priv->links[priv->activeLinks[0]];
1903
1904 /* Determine if all links are still equal */
1905 if (link->conf.latency != link0->conf.latency
1906 || link->conf.bandwidth != link0->conf.bandwidth)
1907 priv->allLinksEqual = 0;
1908
1909 /* Initialize rec'd sequence number */
1910 if (link->seq == MP_NOSEQ) {
1911 link->seq = (link == link0) ?
1912 MP_INITIAL_SEQ : link0->seq;
1913 }
1914 } else
1915 link->seq = MP_NOSEQ;
1916 }
1917
1918 /* Update MP state as multi-link is active or not */
1919 if (priv->conf.enableMultilink && priv->numActiveLinks > 0)
1920 ng_ppp_start_frag_timer(node);
1921 else {
1922 ng_ppp_stop_frag_timer(node);
1923 ng_ppp_frag_reset(node);
1924 priv->xseq = MP_INITIAL_SEQ;
1925 priv->mseq = MP_INITIAL_SEQ;
1926 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1927 struct ng_ppp_link *const link = &priv->links[i];
1928
1929 bzero(&link->lastWrite, sizeof(link->lastWrite));
1930 link->bytesInQueue = 0;
1931 link->seq = MP_NOSEQ;
1932 }
1933 }
1934}
1935
1936/*
1937 * Determine if a new configuration would represent a valid change
1938 * from the current configuration and link activity status.
1939 */
1940static int
1941ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf)
1942{
1943 const priv_p priv = node->private;
1944 int i, newNumLinksActive;
1945
1946 /* Check per-link config and count how many links would be active */
1947 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) {
1948 if (newConf->links[i].enableLink && priv->links[i].hook != NULL)
1949 newNumLinksActive++;
1950 if (!newConf->links[i].enableLink)
1951 continue;
1952 if (newConf->links[i].mru < MP_MIN_LINK_MRU)
1953 return (0);
1954 if (newConf->links[i].bandwidth == 0)
1955 return (0);
1956 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH)
1957 return (0);
1958 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY)
1959 return (0);
1960 }
1961
1962 /* Check bundle parameters */
1963 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU)
1964 return (0);
1965
1966 /* Disallow changes to multi-link configuration while MP is active */
1967 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) {
1968 if (!priv->conf.enableMultilink
1969 != !newConf->bund.enableMultilink
1970 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq
1971 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq)
1972 return (0);
1973 }
1974
1975 /* At most one link can be active unless multi-link is enabled */
1976 if (!newConf->bund.enableMultilink && newNumLinksActive > 1)
1977 return (0);
1978
1979 /* Configuration change would be valid */
1980 return (1);
1981}
1982
1983/*
1984 * Free all entries in the fragment queue
1985 */
1986static void
1987ng_ppp_frag_reset(node_p node)
1988{
1989 const priv_p priv = node->private;
1990 struct ng_ppp_frag *qent, *qnext;
1991
1992 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) {
1993 qnext = TAILQ_NEXT(qent, f_qent);
1994 NG_FREE_DATA(qent->data, qent->meta);
1995 FREE(qent, M_NETGRAPH);
1996 }
1997 TAILQ_INIT(&priv->frags);
1998 priv->qlen = 0;
1999}
2000
2001/*
2002 * Start fragment queue timer
2003 */
2004static void
2005ng_ppp_start_frag_timer(node_p node)
2006{
2007 const priv_p priv = node->private;
2008
2009 if (!priv->timerActive) {
2010 priv->fragTimer = timeout(ng_ppp_frag_timeout,
2011 node, MP_FRAGTIMER_INTERVAL);
2012 priv->timerActive = 1;
2013 node->refs++;
2014 }
2015}
2016
2017/*
2018 * Stop fragment queue timer
2019 */
2020static void
2021ng_ppp_stop_frag_timer(node_p node)
2022{
2023 const priv_p priv = node->private;
2024
2025 if (priv->timerActive) {
2026 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer);
2027 priv->timerActive = 0;
2028 KASSERT(node->refs > 1,
2029 ("%s: refs=%d", __FUNCTION__, node->refs));
2030 ng_unref(node);
2031 }
2032}
2033
| 346 NG_PPP_NODE_TYPE,
347 NULL,
348 ng_ppp_constructor,
349 ng_ppp_rcvmsg,
350 ng_ppp_rmnode,
351 ng_ppp_newhook,
352 NULL,
353 NULL,
354 ng_ppp_rcvdata,
355 ng_ppp_disconnect,
356 ng_ppp_cmds
357};
358NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
359
360static int *compareLatencies; /* hack for ng_ppp_intcmp() */
361
362/* Address and control field header */
363static const u_char ng_ppp_acf[2] = { 0xff, 0x03 };
364
365/* Maximum time we'll let a complete incoming packet sit in the queue */
366static const struct timeval ng_ppp_max_staleness = { 2, 0 }; /* 2 seconds */
367
368#define ERROUT(x) do { error = (x); goto done; } while (0)
369
370/************************************************************************
371 NETGRAPH NODE STUFF
372 ************************************************************************/
373
374/*
375 * Node type constructor
376 */
377static int
378ng_ppp_constructor(node_p *nodep)
379{
380 priv_p priv;
381 int i, error;
382
383 /* Allocate private structure */
384 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
385 if (priv == NULL)
386 return (ENOMEM);
387
388 /* Call generic node constructor */
389 if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) {
390 FREE(priv, M_NETGRAPH);
391 return (error);
392 }
393 (*nodep)->private = priv;
394
395 /* Initialize state */
396 TAILQ_INIT(&priv->frags);
397 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
398 priv->links[i].seq = MP_NOSEQ;
399 callout_handle_init(&priv->fragTimer);
400
401 /* Done */
402 return (0);
403}
404
405/*
406 * Give our OK for a hook to be added
407 */
408static int
409ng_ppp_newhook(node_p node, hook_p hook, const char *name)
410{
411 const priv_p priv = node->private;
412 int linkNum = -1;
413 hook_p *hookPtr = NULL;
414 int hookIndex = -1;
415
416 /* Figure out which hook it is */
417 if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
418 strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
419 const char *cp;
420 char *eptr;
421
422 cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
423 if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
424 return (EINVAL);
425 linkNum = (int)strtoul(cp, &eptr, 10);
426 if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
427 return (EINVAL);
428 hookPtr = &priv->links[linkNum].hook;
429 hookIndex = ~linkNum;
430 } else { /* must be a non-link hook */
431 int i;
432
433 for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
434 if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
435 hookPtr = &priv->hooks[i];
436 hookIndex = i;
437 break;
438 }
439 }
440 if (ng_ppp_hook_names[i] == NULL)
441 return (EINVAL); /* no such hook */
442 }
443
444 /* See if hook is already connected */
445 if (*hookPtr != NULL)
446 return (EISCONN);
447
448 /* Disallow more than one link unless multilink is enabled */
449 if (linkNum != -1 && priv->links[linkNum].conf.enableLink
450 && !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
451 return (ENODEV);
452
453 /* OK */
454 *hookPtr = hook;
455 HOOK_INDEX(hook) = hookIndex;
456 ng_ppp_update(node, 0);
457 return (0);
458}
459
460/*
461 * Receive a control message
462 */
463static int
464ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg,
465 const char *raddr, struct ng_mesg **rptr, hook_p lasthook)
466{
467 const priv_p priv = node->private;
468 struct ng_mesg *resp = NULL;
469 int error = 0;
470
471 switch (msg->header.typecookie) {
472 case NGM_PPP_COOKIE:
473 switch (msg->header.cmd) {
474 case NGM_PPP_SET_CONFIG:
475 {
476 struct ng_ppp_node_conf *const conf =
477 (struct ng_ppp_node_conf *)msg->data;
478 int i;
479
480 /* Check for invalid or illegal config */
481 if (msg->header.arglen != sizeof(*conf))
482 ERROUT(EINVAL);
483 if (!ng_ppp_config_valid(node, conf))
484 ERROUT(EINVAL);
485
486 /* Copy config */
487 priv->conf = conf->bund;
488 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
489 priv->links[i].conf = conf->links[i];
490 ng_ppp_update(node, 1);
491 break;
492 }
493 case NGM_PPP_GET_CONFIG:
494 {
495 struct ng_ppp_node_conf *conf;
496 int i;
497
498 NG_MKRESPONSE(resp, msg, sizeof(*conf), M_NOWAIT);
499 if (resp == NULL)
500 ERROUT(ENOMEM);
501 conf = (struct ng_ppp_node_conf *)resp->data;
502 conf->bund = priv->conf;
503 for (i = 0; i < NG_PPP_MAX_LINKS; i++)
504 conf->links[i] = priv->links[i].conf;
505 break;
506 }
507 case NGM_PPP_GET_MP_STATE:
508 {
509 struct ng_ppp_mp_state *info;
510 int i;
511
512 NG_MKRESPONSE(resp, msg, sizeof(*info), M_NOWAIT);
513 if (resp == NULL)
514 ERROUT(ENOMEM);
515 info = (struct ng_ppp_mp_state *)resp->data;
516 bzero(info, sizeof(*info));
517 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
518 if (priv->links[i].seq != MP_NOSEQ)
519 info->rseq[i] = priv->links[i].seq;
520 }
521 info->mseq = priv->mseq;
522 info->xseq = priv->xseq;
523 break;
524 }
525 case NGM_PPP_GET_LINK_STATS:
526 case NGM_PPP_CLR_LINK_STATS:
527 case NGM_PPP_GETCLR_LINK_STATS:
528 {
529 struct ng_ppp_link_stat *stats;
530 u_int16_t linkNum;
531
532 if (msg->header.arglen != sizeof(u_int16_t))
533 ERROUT(EINVAL);
534 linkNum = *((u_int16_t *) msg->data);
535 if (linkNum >= NG_PPP_MAX_LINKS
536 && linkNum != NG_PPP_BUNDLE_LINKNUM)
537 ERROUT(EINVAL);
538 stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ?
539 &priv->bundleStats : &priv->links[linkNum].stats;
540 if (msg->header.cmd != NGM_PPP_CLR_LINK_STATS) {
541 NG_MKRESPONSE(resp, msg,
542 sizeof(struct ng_ppp_link_stat), M_NOWAIT);
543 if (resp == NULL)
544 ERROUT(ENOMEM);
545 bcopy(stats, resp->data, sizeof(*stats));
546 }
547 if (msg->header.cmd != NGM_PPP_GET_LINK_STATS)
548 bzero(stats, sizeof(*stats));
549 break;
550 }
551 default:
552 error = EINVAL;
553 break;
554 }
555 break;
556 case NGM_VJC_COOKIE:
557 {
558 char path[NG_PATHLEN + 1];
559 node_p origNode;
560
561 if ((error = ng_path2node(node, raddr, &origNode, NULL)) != 0)
562 ERROUT(error);
563 snprintf(path, sizeof(path), "[%lx]:%s",
564 (long)node->ID, NG_PPP_HOOK_VJC_IP);
565 return ng_send_msg(origNode, msg, path, NULL, NULL, rptr);
566 }
567 default:
568 error = EINVAL;
569 break;
570 }
571 if (rptr)
572 *rptr = resp;
573 else if (resp)
574 FREE(resp, M_NETGRAPH);
575
576done:
577 FREE(msg, M_NETGRAPH);
578 return (error);
579}
580
581/*
582 * Receive data on a hook
583 */
584static int
585ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
586 struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
587{
588 const node_p node = hook->node;
589 const priv_p priv = node->private;
590 const int index = HOOK_INDEX(hook);
591 u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
592 hook_p outHook = NULL;
593 int proto = 0, error;
594
595 /* Did it come from a link hook? */
596 if (index < 0) {
597 struct ng_ppp_link *link;
598
599 /* Convert index into a link number */
600 linkNum = (u_int16_t)~index;
601 KASSERT(linkNum < NG_PPP_MAX_LINKS,
602 ("%s: bogus index 0x%x", __FUNCTION__, index));
603 link = &priv->links[linkNum];
604
605 /* Stats */
606 link->stats.recvFrames++;
607 link->stats.recvOctets += m->m_pkthdr.len;
608
609 /* Strip address and control fields, if present */
610 if (m->m_pkthdr.len >= 2) {
611 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
612 NG_FREE_DATA(m, meta);
613 return (ENOBUFS);
614 }
615 if (bcmp(mtod(m, u_char *), &ng_ppp_acf, 2) == 0)
616 m_adj(m, 2);
617 }
618
619 /* Dispatch incoming frame (if not enabled, to bypass) */
620 return ng_ppp_input(node,
621 !link->conf.enableLink, linkNum, m, meta);
622 }
623
624 /* Get protocol & check if data allowed from this hook */
625 switch (index) {
626
627 /* Outgoing data */
628 case HOOK_INDEX_ATALK:
629 if (!priv->conf.enableAtalk) {
630 NG_FREE_DATA(m, meta);
631 return (ENXIO);
632 }
633 proto = PROT_APPLETALK;
634 break;
635 case HOOK_INDEX_IPX:
636 if (!priv->conf.enableIPX) {
637 NG_FREE_DATA(m, meta);
638 return (ENXIO);
639 }
640 proto = PROT_IPX;
641 break;
642 case HOOK_INDEX_IPV6:
643 if (!priv->conf.enableIPv6) {
644 NG_FREE_DATA(m, meta);
645 return (ENXIO);
646 }
647 proto = PROT_IPV6;
648 break;
649 case HOOK_INDEX_INET:
650 case HOOK_INDEX_VJC_VJIP:
651 if (!priv->conf.enableIP) {
652 NG_FREE_DATA(m, meta);
653 return (ENXIO);
654 }
655 proto = PROT_IP;
656 break;
657 case HOOK_INDEX_VJC_COMP:
658 if (!priv->conf.enableVJCompression) {
659 NG_FREE_DATA(m, meta);
660 return (ENXIO);
661 }
662 proto = PROT_VJCOMP;
663 break;
664 case HOOK_INDEX_VJC_UNCOMP:
665 if (!priv->conf.enableVJCompression) {
666 NG_FREE_DATA(m, meta);
667 return (ENXIO);
668 }
669 proto = PROT_VJUNCOMP;
670 break;
671 case HOOK_INDEX_COMPRESS:
672 if (!priv->conf.enableCompression) {
673 NG_FREE_DATA(m, meta);
674 return (ENXIO);
675 }
676 proto = PROT_COMPD;
677 break;
678 case HOOK_INDEX_ENCRYPT:
679 if (!priv->conf.enableEncryption) {
680 NG_FREE_DATA(m, meta);
681 return (ENXIO);
682 }
683 proto = PROT_CRYPTD;
684 break;
685 case HOOK_INDEX_BYPASS:
686 if (m->m_pkthdr.len < 4) {
687 NG_FREE_DATA(m, meta);
688 return (EINVAL);
689 }
690 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
691 NG_FREE_META(meta);
692 return (ENOBUFS);
693 }
694 linkNum = ntohs(mtod(m, u_int16_t *)[0]);
695 proto = ntohs(mtod(m, u_int16_t *)[1]);
696 m_adj(m, 4);
697 if (linkNum >= NG_PPP_MAX_LINKS
698 && linkNum != NG_PPP_BUNDLE_LINKNUM) {
699 NG_FREE_DATA(m, meta);
700 return (EINVAL);
701 }
702 break;
703
704 /* Incoming data */
705 case HOOK_INDEX_VJC_IP:
706 if (!priv->conf.enableIP || !priv->conf.enableVJDecompression) {
707 NG_FREE_DATA(m, meta);
708 return (ENXIO);
709 }
710 break;
711 case HOOK_INDEX_DECOMPRESS:
712 if (!priv->conf.enableDecompression) {
713 NG_FREE_DATA(m, meta);
714 return (ENXIO);
715 }
716 break;
717 case HOOK_INDEX_DECRYPT:
718 if (!priv->conf.enableDecryption) {
719 NG_FREE_DATA(m, meta);
720 return (ENXIO);
721 }
722 break;
723 default:
724 panic("%s: bogus index 0x%x", __FUNCTION__, index);
725 }
726
727 /* Now figure out what to do with the frame */
728 switch (index) {
729
730 /* Outgoing data */
731 case HOOK_INDEX_INET:
732 if (priv->conf.enableVJCompression && priv->vjCompHooked) {
733 outHook = priv->hooks[HOOK_INDEX_VJC_IP];
734 break;
735 }
736 /* FALLTHROUGH */
737 case HOOK_INDEX_ATALK:
738 case HOOK_INDEX_IPV6:
739 case HOOK_INDEX_IPX:
740 case HOOK_INDEX_VJC_COMP:
741 case HOOK_INDEX_VJC_UNCOMP:
742 case HOOK_INDEX_VJC_VJIP:
743 if (priv->conf.enableCompression
744 && priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
745 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
746 NG_FREE_META(meta);
747 return (ENOBUFS);
748 }
749 outHook = priv->hooks[HOOK_INDEX_COMPRESS];
750 break;
751 }
752 /* FALLTHROUGH */
753 case HOOK_INDEX_COMPRESS:
754 if (priv->conf.enableEncryption
755 && priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
756 if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
757 NG_FREE_META(meta);
758 return (ENOBUFS);
759 }
760 outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
761 break;
762 }
763 /* FALLTHROUGH */
764 case HOOK_INDEX_ENCRYPT:
765 return ng_ppp_output(node, 0,
766 proto, NG_PPP_BUNDLE_LINKNUM, m, meta);
767
768 case HOOK_INDEX_BYPASS:
769 return ng_ppp_output(node, 1, proto, linkNum, m, meta);
770
771 /* Incoming data */
772 case HOOK_INDEX_DECRYPT:
773 case HOOK_INDEX_DECOMPRESS:
774 return ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
775
776 case HOOK_INDEX_VJC_IP:
777 outHook = priv->hooks[HOOK_INDEX_INET];
778 break;
779 }
780
781 /* Send packet out hook */
782 NG_SEND_DATA_RET(error, outHook, m, meta, resp);
783 if (m != NULL || meta != NULL)
784 return ng_ppp_rcvdata(outHook, m, meta, NULL, NULL, resp);
785 return (error);
786}
787
788/*
789 * Destroy node
790 */
791static int
792ng_ppp_rmnode(node_p node)
793{
794 const priv_p priv = node->private;
795
796 /* Stop fragment queue timer */
797 ng_ppp_stop_frag_timer(node);
798
799 /* Take down netgraph node */
800 node->flags |= NG_INVALID;
801 ng_cutlinks(node);
802 ng_unname(node);
803 ng_ppp_frag_reset(node);
804 bzero(priv, sizeof(*priv));
805 FREE(priv, M_NETGRAPH);
806 node->private = NULL;
807 ng_unref(node); /* let the node escape */
808 return (0);
809}
810
811/*
812 * Hook disconnection
813 */
814static int
815ng_ppp_disconnect(hook_p hook)
816{
817 const node_p node = hook->node;
818 const priv_p priv = node->private;
819 const int index = HOOK_INDEX(hook);
820
821 /* Zero out hook pointer */
822 if (index < 0)
823 priv->links[~index].hook = NULL;
824 else
825 priv->hooks[index] = NULL;
826
827 /* Update derived info (or go away if no hooks left) */
828 if (node->numhooks > 0)
829 ng_ppp_update(node, 0);
830 else
831 ng_rmnode(node);
832 return (0);
833}
834
835/************************************************************************
836 HELPER STUFF
837 ************************************************************************/
838
839/*
840 * Handle an incoming frame. Extract the PPP protocol number
841 * and dispatch accordingly.
842 */
843static int
844ng_ppp_input(node_p node, int bypass, int linkNum, struct mbuf *m, meta_p meta)
845{
846 const priv_p priv = node->private;
847 hook_p outHook = NULL;
848 int proto, error;
849
850 /* Extract protocol number */
851 for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
852 if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
853 NG_FREE_META(meta);
854 return (ENOBUFS);
855 }
856 proto = (proto << 8) + *mtod(m, u_char *);
857 m_adj(m, 1);
858 }
859 if (!PROT_VALID(proto)) {
860 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
861 priv->bundleStats.badProtos++;
862 else
863 priv->links[linkNum].stats.badProtos++;
864 NG_FREE_DATA(m, meta);
865 return (EINVAL);
866 }
867
868 /* Bypass frame? */
869 if (bypass)
870 goto bypass;
871
872 /* Check protocol */
873 switch (proto) {
874 case PROT_COMPD:
875 if (priv->conf.enableDecompression)
876 outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
877 break;
878 case PROT_CRYPTD:
879 if (priv->conf.enableDecryption)
880 outHook = priv->hooks[HOOK_INDEX_DECRYPT];
881 break;
882 case PROT_VJCOMP:
883 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
884 outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
885 break;
886 case PROT_VJUNCOMP:
887 if (priv->conf.enableVJDecompression && priv->vjCompHooked)
888 outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
889 break;
890 case PROT_MP:
891 if (priv->conf.enableMultilink
892 && linkNum != NG_PPP_BUNDLE_LINKNUM)
893 return ng_ppp_mp_input(node, linkNum, m, meta);
894 break;
895 case PROT_APPLETALK:
896 if (priv->conf.enableAtalk)
897 outHook = priv->hooks[HOOK_INDEX_ATALK];
898 break;
899 case PROT_IPX:
900 if (priv->conf.enableIPX)
901 outHook = priv->hooks[HOOK_INDEX_IPX];
902 break;
903 case PROT_IP:
904 if (priv->conf.enableIP)
905 outHook = priv->hooks[HOOK_INDEX_INET];
906 break;
907 case PROT_IPV6:
908 if (priv->conf.enableIPv6)
909 outHook = priv->hooks[HOOK_INDEX_IPV6];
910 break;
911 }
912
913bypass:
914 /* For unknown/inactive protocols, forward out the bypass hook */
915 if (outHook == NULL) {
916 u_int16_t hdr[2];
917
918 hdr[0] = htons(linkNum);
919 hdr[1] = htons((u_int16_t)proto);
920 if ((m = ng_ppp_prepend(m, &hdr, 4)) == NULL) {
921 NG_FREE_META(meta);
922 return (ENOBUFS);
923 }
924 outHook = priv->hooks[HOOK_INDEX_BYPASS];
925 }
926
927 /* Forward frame */
928 NG_SEND_DATA(error, outHook, m, meta);
929 return (error);
930}
931
932/*
933 * Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM
934 * If the link is not enabled then ENXIO is returned, unless "bypass" is != 0.
935 */
936static int
937ng_ppp_output(node_p node, int bypass,
938 int proto, int linkNum, struct mbuf *m, meta_p meta)
939{
940 const priv_p priv = node->private;
941 struct ng_ppp_link *link;
942 int len, error;
943
944 /* If not doing MP, map bundle virtual link to (the only) link */
945 if (linkNum == NG_PPP_BUNDLE_LINKNUM && !priv->conf.enableMultilink)
946 linkNum = priv->activeLinks[0];
947
948 /* Get link pointer (optimization) */
949 link = (linkNum != NG_PPP_BUNDLE_LINKNUM) ?
950 &priv->links[linkNum] : NULL;
951
952 /* Check link status (if real) */
953 if (linkNum != NG_PPP_BUNDLE_LINKNUM) {
954 if (!bypass && !link->conf.enableLink) {
955 NG_FREE_DATA(m, meta);
956 return (ENXIO);
957 }
958 if (link->hook == NULL) {
959 NG_FREE_DATA(m, meta);
960 return (ENETDOWN);
961 }
962 }
963
964 /* Prepend protocol number, possibly compressed */
965 if ((m = ng_ppp_addproto(m, proto,
966 linkNum == NG_PPP_BUNDLE_LINKNUM
967 || link->conf.enableProtoComp)) == NULL) {
968 NG_FREE_META(meta);
969 return (ENOBUFS);
970 }
971
972 /* Special handling for the MP virtual link */
973 if (linkNum == NG_PPP_BUNDLE_LINKNUM)
974 return ng_ppp_mp_output(node, m, meta);
975
976 /* Prepend address and control field (unless compressed) */
977 if (proto == PROT_LCP || !link->conf.enableACFComp) {
978 if ((m = ng_ppp_prepend(m, &ng_ppp_acf, 2)) == NULL) {
979 NG_FREE_META(meta);
980 return (ENOBUFS);
981 }
982 }
983
984 /* Deliver frame */
985 len = m->m_pkthdr.len;
986 NG_SEND_DATA(error, link->hook, m, meta);
987
988 /* Update stats and 'bytes in queue' counter */
989 if (error == 0) {
990 link->stats.xmitFrames++;
991 link->stats.xmitOctets += len;
992 link->bytesInQueue += len;
993 getmicrouptime(&link->lastWrite);
994 }
995 return error;
996}
997
998/*
999 * Handle an incoming multi-link fragment
1000 *
1001 * The fragment reassembly algorithm is somewhat complex. This is mainly
1002 * because we are required not to reorder the reconstructed packets, yet
1003 * fragments are only guaranteed to arrive in order on a per-link basis.
1004 * In other words, when we have a complete packet ready, but the previous
1005 * packet is still incomplete, we have to decide between delivering the
1006 * complete packet and throwing away the incomplete one, or waiting to
1007 * see if the remainder of the incomplete one arrives, at which time we
1008 * can deliver both packets, in order.
1009 *
1010 * This problem is exacerbated by "sequence number slew", which is when
1011 * the sequence numbers coming in from different links are far apart from
1012 * each other. In particular, certain unnamed equipment (*cough* Ascend)
1013 * has been seen to generate sequence number slew of up to 10 on an ISDN
1014 * 2B-channel MP link. There is nothing invalid about sequence number slew
1015 * but it makes the reasssembly process have to work harder.
1016 *
1017 * However, the peer is required to transmit fragments in order on each
1018 * link. That means if we define MSEQ as the minimum over all links of
1019 * the highest sequence number received on that link, then we can always
1020 * give up any hope of receiving a fragment with sequence number < MSEQ in
1021 * the future (all of this using 'wraparound' sequence number space).
1022 * Therefore we can always immediately throw away incomplete packets
1023 * missing fragments with sequence numbers < MSEQ.
1024 *
1025 * Here is an overview of our algorithm:
1026 *
1027 * o Received fragments are inserted into a queue, for which we
1028 * maintain these invariants between calls to this function:
1029 *
1030 * - Fragments are ordered in the queue by sequence number
1031 * - If a complete packet is at the head of the queue, then
1032 * the first fragment in the packet has seq# > MSEQ + 1
1033 * (otherwise, we could deliver it immediately)
1034 * - If any fragments have seq# < MSEQ, then they are necessarily
1035 * part of a packet whose missing seq#'s are all > MSEQ (otherwise,
1036 * we can throw them away because they'll never be completed)
1037 * - The queue contains at most MP_MAX_QUEUE_LEN fragments
1038 *
1039 * o We have a periodic timer that checks the queue for the first
1040 * complete packet that has been sitting in the queue "too long".
1041 * When one is detected, all previous (incomplete) fragments are
1042 * discarded, their missing fragments are declared lost and MSEQ
1043 * is increased.
1044 *
1045 * o If we recieve a fragment with seq# < MSEQ, we throw it away
1046 * because we've already delcared it lost.
1047 *
1048 * This assumes linkNum != NG_PPP_BUNDLE_LINKNUM.
1049 */
1050static int
1051ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
1052{
1053 const priv_p priv = node->private;
1054 struct ng_ppp_link *const link = &priv->links[linkNum];
1055 struct ng_ppp_frag frag0, *frag = &frag0;
1056 struct ng_ppp_frag *qent;
1057 int i, diff, inserted;
1058
1059 /* Stats */
1060 priv->bundleStats.recvFrames++;
1061 priv->bundleStats.recvOctets += m->m_pkthdr.len;
1062
1063 /* Extract fragment information from MP header */
1064 if (priv->conf.recvShortSeq) {
1065 u_int16_t shdr;
1066
1067 if (m->m_pkthdr.len < 2) {
1068 link->stats.runts++;
1069 NG_FREE_DATA(m, meta);
1070 return (EINVAL);
1071 }
1072 if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
1073 NG_FREE_META(meta);
1074 return (ENOBUFS);
1075 }
1076 shdr = ntohs(*mtod(m, u_int16_t *));
1077 frag->seq = MP_SHORT_EXTEND(shdr);
1078 frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
1079 frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
1080 diff = MP_SHORT_SEQ_DIFF(frag->seq, priv->mseq);
1081 m_adj(m, 2);
1082 } else {
1083 u_int32_t lhdr;
1084
1085 if (m->m_pkthdr.len < 4) {
1086 link->stats.runts++;
1087 NG_FREE_DATA(m, meta);
1088 return (EINVAL);
1089 }
1090 if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
1091 NG_FREE_META(meta);
1092 return (ENOBUFS);
1093 }
1094 lhdr = ntohl(*mtod(m, u_int32_t *));
1095 frag->seq = MP_LONG_EXTEND(lhdr);
1096 frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
1097 frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
1098 diff = MP_LONG_SEQ_DIFF(frag->seq, priv->mseq);
1099 m_adj(m, 4);
1100 }
1101 frag->data = m;
1102 frag->meta = meta;
1103 getmicrouptime(&frag->timestamp);
1104
1105 /* If sequence number is < MSEQ, we've already declared this
1106 fragment as lost, so we have no choice now but to drop it */
1107 if (diff < 0) {
1108 link->stats.dropFragments++;
1109 NG_FREE_DATA(m, meta);
1110 return (0);
1111 }
1112
1113 /* Update highest received sequence number on this link and MSEQ */
1114 priv->mseq = link->seq = frag->seq;
1115 for (i = 0; i < priv->numActiveLinks; i++) {
1116 struct ng_ppp_link *const alink =
1117 &priv->links[priv->activeLinks[i]];
1118
1119 if (MP_RECV_SEQ_DIFF(priv, alink->seq, priv->mseq) < 0)
1120 priv->mseq = alink->seq;
1121 }
1122
1123 /* Allocate a new frag struct for the queue */
1124 MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT);
1125 if (frag == NULL) {
1126 NG_FREE_DATA(m, meta);
1127 ng_ppp_frag_process(node);
1128 return (ENOMEM);
1129 }
1130 *frag = frag0;
1131
1132 /* Add fragment to queue, which is sorted by sequence number */
1133 inserted = 0;
1134 TAILQ_FOREACH_REVERSE(qent, &priv->frags, ng_ppp_fraglist, f_qent) {
1135 diff = MP_RECV_SEQ_DIFF(priv, frag->seq, qent->seq);
1136 if (diff > 0) {
1137 TAILQ_INSERT_AFTER(&priv->frags, qent, frag, f_qent);
1138 inserted = 1;
1139 break;
1140 } else if (diff == 0) { /* should never happen! */
1141 link->stats.dupFragments++;
1142 NG_FREE_DATA(frag->data, frag->meta);
1143 FREE(frag, M_NETGRAPH);
1144 return (EINVAL);
1145 }
1146 }
1147 if (!inserted)
1148 TAILQ_INSERT_HEAD(&priv->frags, frag, f_qent);
1149 priv->qlen++;
1150
1151 /* Process the queue */
1152 return ng_ppp_frag_process(node);
1153}
1154
1155/*
1156 * Examine our list of fragments, and determine if there is a
1157 * complete and deliverable packet at the head of the list.
1158 * Return 1 if so, zero otherwise.
1159 */
1160static int
1161ng_ppp_check_packet(node_p node)
1162{
1163 const priv_p priv = node->private;
1164 struct ng_ppp_frag *qent, *qnext;
1165
1166 /* Check for empty queue */
1167 if (TAILQ_EMPTY(&priv->frags))
1168 return (0);
1169
1170 /* Check first fragment is the start of a deliverable packet */
1171 qent = TAILQ_FIRST(&priv->frags);
1172 if (!qent->first || MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) > 1)
1173 return (0);
1174
1175 /* Check that all the fragments are there */
1176 while (!qent->last) {
1177 qnext = TAILQ_NEXT(qent, f_qent);
1178 if (qnext == NULL) /* end of queue */
1179 return (0);
1180 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq))
1181 return (0);
1182 qent = qnext;
1183 }
1184
1185 /* Got one */
1186 return (1);
1187}
1188
1189/*
1190 * Pull a completed packet off the head of the incoming fragment queue.
1191 * This assumes there is a completed packet there to pull off.
1192 */
1193static void
1194ng_ppp_get_packet(node_p node, struct mbuf **mp, meta_p *metap)
1195{
1196 const priv_p priv = node->private;
1197 struct ng_ppp_frag *qent, *qnext;
1198 struct mbuf *m = NULL, *tail;
1199
1200 qent = TAILQ_FIRST(&priv->frags);
1201 KASSERT(!TAILQ_EMPTY(&priv->frags) && qent->first,
1202 ("%s: no packet", __FUNCTION__));
1203 for (tail = NULL; qent != NULL; qent = qnext) {
1204 qnext = TAILQ_NEXT(qent, f_qent);
1205 KASSERT(!TAILQ_EMPTY(&priv->frags),
1206 ("%s: empty q", __FUNCTION__));
1207 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1208 if (tail == NULL) {
1209 tail = m = qent->data;
1210 *metap = qent->meta; /* inherit first frag's meta */
1211 } else {
1212 m->m_pkthdr.len += qent->data->m_pkthdr.len;
1213 tail->m_next = qent->data;
1214 NG_FREE_META(qent->meta); /* drop other frags' metas */
1215 }
1216 while (tail->m_next != NULL)
1217 tail = tail->m_next;
1218 if (qent->last)
1219 qnext = NULL;
1220 FREE(qent, M_NETGRAPH);
1221 priv->qlen--;
1222 }
1223 *mp = m;
1224}
1225
1226/*
1227 * Trim fragments from the queue whose packets can never be completed.
1228 * This assumes a complete packet is NOT at the beginning of the queue.
1229 * Returns 1 if fragments were removed, zero otherwise.
1230 */
1231static int
1232ng_ppp_frag_trim(node_p node)
1233{
1234 const priv_p priv = node->private;
1235 struct ng_ppp_frag *qent, *qnext = NULL;
1236 int removed = 0;
1237
1238 /* Scan for "dead" fragments and remove them */
1239 while (1) {
1240 int dead = 0;
1241
1242 /* If queue is empty, we're done */
1243 if (TAILQ_EMPTY(&priv->frags))
1244 break;
1245
1246 /* Determine whether first fragment can ever be completed */
1247 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1248 if (MP_RECV_SEQ_DIFF(priv, qent->seq, priv->mseq) >= 0)
1249 break;
1250 qnext = TAILQ_NEXT(qent, f_qent);
1251 KASSERT(qnext != NULL,
1252 ("%s: last frag < MSEQ?", __FUNCTION__));
1253 if (qnext->seq != MP_NEXT_RECV_SEQ(priv, qent->seq)
1254 || qent->last || qnext->first) {
1255 dead = 1;
1256 break;
1257 }
1258 }
1259 if (!dead)
1260 break;
1261
1262 /* Remove fragment and all others in the same packet */
1263 while ((qent = TAILQ_FIRST(&priv->frags)) != qnext) {
1264 KASSERT(!TAILQ_EMPTY(&priv->frags),
1265 ("%s: empty q", __FUNCTION__));
1266 priv->bundleStats.dropFragments++;
1267 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1268 NG_FREE_DATA(qent->data, qent->meta);
1269 FREE(qent, M_NETGRAPH);
1270 priv->qlen--;
1271 removed = 1;
1272 }
1273 }
1274 return (removed);
1275}
1276
1277/*
1278 * Run the queue, restoring the queue invariants
1279 */
1280static int
1281ng_ppp_frag_process(node_p node)
1282{
1283 const priv_p priv = node->private;
1284 struct mbuf *m;
1285 meta_p meta;
1286
1287 /* Deliver any deliverable packets */
1288 while (ng_ppp_check_packet(node)) {
1289 ng_ppp_get_packet(node, &m, &meta);
1290 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1291 }
1292
1293 /* Delete dead fragments and try again */
1294 if (ng_ppp_frag_trim(node)) {
1295 while (ng_ppp_check_packet(node)) {
1296 ng_ppp_get_packet(node, &m, &meta);
1297 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1298 }
1299 }
1300
1301 /* Check for stale fragments while we're here */
1302 ng_ppp_frag_checkstale(node);
1303
1304 /* Check queue length */
1305 if (priv->qlen > MP_MAX_QUEUE_LEN) {
1306 struct ng_ppp_frag *qent;
1307 int i;
1308
1309 /* Get oldest fragment */
1310 KASSERT(!TAILQ_EMPTY(&priv->frags),
1311 ("%s: empty q", __FUNCTION__));
1312 qent = TAILQ_FIRST(&priv->frags);
1313
1314 /* Bump MSEQ if necessary */
1315 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, qent->seq) < 0) {
1316 priv->mseq = qent->seq;
1317 for (i = 0; i < priv->numActiveLinks; i++) {
1318 struct ng_ppp_link *const alink =
1319 &priv->links[priv->activeLinks[i]];
1320
1321 if (MP_RECV_SEQ_DIFF(priv,
1322 alink->seq, priv->mseq) < 0)
1323 alink->seq = priv->mseq;
1324 }
1325 }
1326
1327 /* Drop it */
1328 priv->bundleStats.dropFragments++;
1329 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1330 NG_FREE_DATA(qent->data, qent->meta);
1331 FREE(qent, M_NETGRAPH);
1332 priv->qlen--;
1333
1334 /* Process queue again */
1335 return ng_ppp_frag_process(node);
1336 }
1337
1338 /* Done */
1339 return (0);
1340}
1341
1342/*
1343 * Check for 'stale' completed packets that need to be delivered
1344 *
1345 * If a link goes down or has a temporary failure, MSEQ can get
1346 * "stuck", because no new incoming fragments appear on that link.
1347 * This can cause completed packets to never get delivered if
1348 * their sequence numbers are all > MSEQ + 1.
1349 *
1350 * This routine checks how long all of the completed packets have
1351 * been sitting in the queue, and if too long, removes fragments
1352 * from the queue and increments MSEQ to allow them to be delivered.
1353 */
1354static void
1355ng_ppp_frag_checkstale(node_p node)
1356{
1357 const priv_p priv = node->private;
1358 struct ng_ppp_frag *qent, *beg, *end;
1359 struct timeval now, age;
1360 struct mbuf *m;
1361 meta_p meta;
1362 int i, seq;
1363
1364 now.tv_sec = 0; /* uninitialized state */
1365 while (1) {
1366
1367 /* If queue is empty, we're done */
1368 if (TAILQ_EMPTY(&priv->frags))
1369 break;
1370
1371 /* Find the first complete packet in the queue */
1372 beg = end = NULL;
1373 seq = TAILQ_FIRST(&priv->frags)->seq;
1374 TAILQ_FOREACH(qent, &priv->frags, f_qent) {
1375 if (qent->first)
1376 beg = qent;
1377 else if (qent->seq != seq)
1378 beg = NULL;
1379 if (beg != NULL && qent->last) {
1380 end = qent;
1381 break;
1382 }
1383 seq = MP_NEXT_RECV_SEQ(priv, seq);
1384 }
1385
1386 /* If none found, exit */
1387 if (end == NULL)
1388 break;
1389
1390 /* Get current time (we assume we've been up for >= 1 second) */
1391 if (now.tv_sec == 0)
1392 getmicrouptime(&now);
1393
1394 /* Check if packet has been queued too long */
1395 age = now;
1396 timevalsub(&age, &beg->timestamp);
1397 if (timevalcmp(&age, &ng_ppp_max_staleness, < ))
1398 break;
1399
1400 /* Throw away junk fragments in front of the completed packet */
1401 while ((qent = TAILQ_FIRST(&priv->frags)) != beg) {
1402 KASSERT(!TAILQ_EMPTY(&priv->frags),
1403 ("%s: empty q", __FUNCTION__));
1404 priv->bundleStats.dropFragments++;
1405 TAILQ_REMOVE(&priv->frags, qent, f_qent);
1406 NG_FREE_DATA(qent->data, qent->meta);
1407 FREE(qent, M_NETGRAPH);
1408 priv->qlen--;
1409 }
1410
1411 /* Extract completed packet */
1412 ng_ppp_get_packet(node, &m, &meta);
1413
1414 /* Bump MSEQ if necessary */
1415 if (MP_RECV_SEQ_DIFF(priv, priv->mseq, end->seq) < 0) {
1416 priv->mseq = end->seq;
1417 for (i = 0; i < priv->numActiveLinks; i++) {
1418 struct ng_ppp_link *const alink =
1419 &priv->links[priv->activeLinks[i]];
1420
1421 if (MP_RECV_SEQ_DIFF(priv,
1422 alink->seq, priv->mseq) < 0)
1423 alink->seq = priv->mseq;
1424 }
1425 }
1426
1427 /* Deliver packet */
1428 ng_ppp_input(node, 0, NG_PPP_BUNDLE_LINKNUM, m, meta);
1429 }
1430}
1431
1432/*
1433 * Periodically call ng_ppp_frag_checkstale()
1434 */
1435static void
1436ng_ppp_frag_timeout(void *arg)
1437{
1438 const node_p node = arg;
1439 const priv_p priv = node->private;
1440 int s = splnet();
1441
1442 /* Handle the race where shutdown happens just before splnet() above */
1443 if ((node->flags & NG_INVALID) != 0) {
1444 ng_unref(node);
1445 splx(s);
1446 return;
1447 }
1448
1449 /* Reset timer state after timeout */
1450 KASSERT(priv->timerActive, ("%s: !timerActive", __FUNCTION__));
1451 priv->timerActive = 0;
1452 KASSERT(node->refs > 1, ("%s: refs=%d", __FUNCTION__, node->refs));
1453 ng_unref(node);
1454
1455 /* Start timer again */
1456 ng_ppp_start_frag_timer(node);
1457
1458 /* Scan the fragment queue */
1459 ng_ppp_frag_checkstale(node);
1460 splx(s);
1461}
1462
1463/*
1464 * Deliver a frame out on the bundle, i.e., figure out how to fragment
1465 * the frame across the individual PPP links and do so.
1466 */
1467static int
1468ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
1469{
1470 const priv_p priv = node->private;
1471 int distrib[NG_PPP_MAX_LINKS];
1472 int firstFragment;
1473 int activeLinkNum;
1474
1475 /* At least one link must be active */
1476 if (priv->numActiveLinks == 0) {
1477 NG_FREE_DATA(m, meta);
1478 return (ENETDOWN);
1479 }
1480
1481 /* Round-robin strategy */
1482 if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
1483 activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
1484 bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
1485 distrib[activeLinkNum] = m->m_pkthdr.len;
1486 goto deliver;
1487 }
1488
1489 /* Strategy when all links are equivalent (optimize the common case) */
1490 if (priv->allLinksEqual) {
1491 const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
1492 int i, remain;
1493
1494 for (i = 0; i < priv->numActiveLinks; i++)
1495 distrib[priv->lastLink++ % priv->numActiveLinks]
1496 = fraction;
1497 remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
1498 while (remain > 0) {
1499 distrib[priv->lastLink++ % priv->numActiveLinks]++;
1500 remain--;
1501 }
1502 goto deliver;
1503 }
1504
1505 /* Strategy when all links are not equivalent */
1506 ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
1507
1508deliver:
1509 /* Update stats */
1510 priv->bundleStats.xmitFrames++;
1511 priv->bundleStats.xmitOctets += m->m_pkthdr.len;
1512
1513 /* Send alloted portions of frame out on the link(s) */
1514 for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
1515 activeLinkNum >= 0; activeLinkNum--) {
1516 const int linkNum = priv->activeLinks[activeLinkNum];
1517 struct ng_ppp_link *const link = &priv->links[linkNum];
1518
1519 /* Deliver fragment(s) out the next link */
1520 for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
1521 int len, lastFragment, error;
1522 struct mbuf *m2;
1523 meta_p meta2;
1524
1525 /* Calculate fragment length; don't exceed link MTU */
1526 len = distrib[activeLinkNum];
1527 if (len > link->conf.mru)
1528 len = link->conf.mru;
1529 distrib[activeLinkNum] -= len;
1530 lastFragment = (len == m->m_pkthdr.len);
1531
1532 /* Split off next fragment as "m2" */
1533 m2 = m;
1534 if (!lastFragment) {
1535 struct mbuf *n = m_split(m, len, M_NOWAIT);
1536
1537 if (n == NULL) {
1538 NG_FREE_DATA(m, meta);
1539 return (ENOMEM);
1540 }
1541 m = n;
1542 }
1543
1544 /* Prepend MP header */
1545 if (priv->conf.xmitShortSeq) {
1546 u_int16_t shdr;
1547
1548 shdr = priv->xseq;
1549 priv->xseq =
1550 (priv->xseq + 1) & MP_SHORT_SEQ_MASK;
1551 if (firstFragment)
1552 shdr |= MP_SHORT_FIRST_FLAG;
1553 if (lastFragment)
1554 shdr |= MP_SHORT_LAST_FLAG;
1555 shdr = htons(shdr);
1556 m2 = ng_ppp_prepend(m2, &shdr, 2);
1557 } else {
1558 u_int32_t lhdr;
1559
1560 lhdr = priv->xseq;
1561 priv->xseq =
1562 (priv->xseq + 1) & MP_LONG_SEQ_MASK;
1563 if (firstFragment)
1564 lhdr |= MP_LONG_FIRST_FLAG;
1565 if (lastFragment)
1566 lhdr |= MP_LONG_LAST_FLAG;
1567 lhdr = htonl(lhdr);
1568 m2 = ng_ppp_prepend(m2, &lhdr, 4);
1569 }
1570 if (m2 == NULL) {
1571 if (!lastFragment)
1572 m_freem(m);
1573 NG_FREE_META(meta);
1574 return (ENOBUFS);
1575 }
1576
1577 /* Copy the meta information, if any */
1578 meta2 = lastFragment ? meta : ng_copy_meta(meta);
1579
1580 /* Send fragment */
1581 error = ng_ppp_output(node, 0,
1582 PROT_MP, linkNum, m2, meta2);
1583 if (error != 0) {
1584 if (!lastFragment)
1585 NG_FREE_DATA(m, meta);
1586 return (error);
1587 }
1588 }
1589 }
1590
1591 /* Done */
1592 return (0);
1593}
1594
1595/*
1596 * Computing the optimal fragmentation
1597 * -----------------------------------
1598 *
1599 * This routine tries to compute the optimal fragmentation pattern based
1600 * on each link's latency, bandwidth, and calculated additional latency.
1601 * The latter quantity is the additional latency caused by previously
1602 * written data that has not been transmitted yet.
1603 *
1604 * This algorithm is only useful when not all of the links have the
1605 * same latency and bandwidth values.
1606 *
1607 * The essential idea is to make the last bit of each fragment of the
1608 * frame arrive at the opposite end at the exact same time. This greedy
1609 * algorithm is optimal, in that no other scheduling could result in any
1610 * packet arriving any sooner unless packets are delivered out of order.
1611 *
1612 * Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and
1613 * latency l_i (in miliseconds). Consider the function function f_i(t)
1614 * which is equal to the number of bytes that will have arrived at
1615 * the peer after t miliseconds if we start writing continuously at
1616 * time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i).
1617 * That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i).
1618 * Note that the y-intersect is always <= zero because latency can't be
1619 * negative. Note also that really the function is f_i(t) except when
1620 * f_i(t) is negative, in which case the function is zero. To take
1621 * care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }.
1622 * So the actual number of bytes that will have arrived at the peer after
1623 * t miliseconds is f_i(t) * Q_i(t).
1624 *
1625 * At any given time, each link has some additional latency a_i >= 0
1626 * due to previously written fragment(s) which are still in the queue.
1627 * This value is easily computed from the time since last transmission,
1628 * the previous latency value, the number of bytes written, and the
1629 * link's bandwidth.
1630 *
1631 * Assume that l_i includes any a_i already, and that the links are
1632 * sorted by latency, so that l_i <= l_{i+1}.
1633 *
1634 * Let N be the total number of bytes in the current frame we are sending.
1635 *
1636 * Suppose we were to start writing bytes at time t = 0 on all links
1637 * simultaneously, which is the most we can possibly do. Then let
1638 * F(t) be equal to the total number of bytes received by the peer
1639 * after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)).
1640 *
1641 * Our goal is simply this: fragment the frame across the links such
1642 * that the peer is able to reconstruct the completed frame as soon as
1643 * possible, i.e., at the least possible value of t. Call this value t_0.
1644 *
1645 * Then it follows that F(t_0) = N. Our strategy is first to find the value
1646 * of t_0, and then deduce how many bytes to write to each link.
1647 *
1648 * Rewriting F(t_0):
1649 *
1650 * t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) )
1651 *
1652 * Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will
1653 * lie in one of these ranges. To find it, we just need to find the i such
1654 * that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values
1655 * for Q_i() in this range, plug in the remaining values, solving for t_0.
1656 *
1657 * Once t_0 is known, then the number of bytes to send on link i is
1658 * just f_i(t_0) * Q_i(t_0).
1659 *
1660 * In other words, we start allocating bytes to the links one at a time.
1661 * We keep adding links until the frame is completely sent. Some links
1662 * may not get any bytes because their latency is too high.
1663 *
1664 * Is all this work really worth the trouble? Depends on the situation.
1665 * The bigger the ratio of computer speed to link speed, and the more
1666 * important total bundle latency is (e.g., for interactive response time),
1667 * the more it's worth it. There is however the cost of calling this
1668 * function for every frame. The running time is O(n^2) where n is the
1669 * number of links that receive a non-zero number of bytes.
1670 *
1671 * Since latency is measured in miliseconds, the "resolution" of this
1672 * algorithm is one milisecond.
1673 *
1674 * To avoid this algorithm altogether, configure all links to have the
1675 * same latency and bandwidth.
1676 */
1677static void
1678ng_ppp_mp_strategy(node_p node, int len, int *distrib)
1679{
1680 const priv_p priv = node->private;
1681 int latency[NG_PPP_MAX_LINKS];
1682 int sortByLatency[NG_PPP_MAX_LINKS];
1683 int activeLinkNum;
1684 int t0, total, topSum, botSum;
1685 struct timeval now;
1686 int i, numFragments;
1687
1688 /* If only one link, this gets real easy */
1689 if (priv->numActiveLinks == 1) {
1690 distrib[0] = len;
1691 return;
1692 }
1693
1694 /* Get current time */
1695 getmicrouptime(&now);
1696
1697 /* Compute latencies for each link at this point in time */
1698 for (activeLinkNum = 0;
1699 activeLinkNum < priv->numActiveLinks; activeLinkNum++) {
1700 struct ng_ppp_link *alink;
1701 struct timeval diff;
1702 int xmitBytes;
1703
1704 /* Start with base latency value */
1705 alink = &priv->links[priv->activeLinks[activeLinkNum]];
1706 latency[activeLinkNum] = alink->conf.latency;
1707 sortByLatency[activeLinkNum] = activeLinkNum; /* see below */
1708
1709 /* Any additional latency? */
1710 if (alink->bytesInQueue == 0)
1711 continue;
1712
1713 /* Compute time delta since last write */
1714 diff = now;
1715 timevalsub(&diff, &alink->lastWrite);
1716 if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */
1717 alink->bytesInQueue = 0;
1718 continue;
1719 }
1720
1721 /* How many bytes could have transmitted since last write? */
1722 xmitBytes = (alink->conf.bandwidth * diff.tv_sec)
1723 + (alink->conf.bandwidth * (diff.tv_usec / 1000)) / 100;
1724 alink->bytesInQueue -= xmitBytes;
1725 if (alink->bytesInQueue < 0)
1726 alink->bytesInQueue = 0;
1727 else
1728 latency[activeLinkNum] +=
1729 (100 * alink->bytesInQueue) / alink->conf.bandwidth;
1730 }
1731
1732 /* Sort active links by latency */
1733 compareLatencies = latency;
1734 qsort(sortByLatency,
1735 priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp);
1736 compareLatencies = NULL;
1737
1738 /* Find the interval we need (add links in sortByLatency[] order) */
1739 for (numFragments = 1;
1740 numFragments < priv->numActiveLinks; numFragments++) {
1741 for (total = i = 0; i < numFragments; i++) {
1742 int flowTime;
1743
1744 flowTime = latency[sortByLatency[numFragments]]
1745 - latency[sortByLatency[i]];
1746 total += ((flowTime * priv->links[
1747 priv->activeLinks[sortByLatency[i]]].conf.bandwidth)
1748 + 99) / 100;
1749 }
1750 if (total >= len)
1751 break;
1752 }
1753
1754 /* Solve for t_0 in that interval */
1755 for (topSum = botSum = i = 0; i < numFragments; i++) {
1756 int bw = priv->links[
1757 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1758
1759 topSum += latency[sortByLatency[i]] * bw; /* / 100 */
1760 botSum += bw; /* / 100 */
1761 }
1762 t0 = ((len * 100) + topSum + botSum / 2) / botSum;
1763
1764 /* Compute f_i(t_0) all i */
1765 bzero(distrib, priv->numActiveLinks * sizeof(*distrib));
1766 for (total = i = 0; i < numFragments; i++) {
1767 int bw = priv->links[
1768 priv->activeLinks[sortByLatency[i]]].conf.bandwidth;
1769
1770 distrib[sortByLatency[i]] =
1771 (bw * (t0 - latency[sortByLatency[i]]) + 50) / 100;
1772 total += distrib[sortByLatency[i]];
1773 }
1774
1775 /* Deal with any rounding error */
1776 if (total < len) {
1777 struct ng_ppp_link *fastLink =
1778 &priv->links[priv->activeLinks[sortByLatency[0]]];
1779 int fast = 0;
1780
1781 /* Find the fastest link */
1782 for (i = 1; i < numFragments; i++) {
1783 struct ng_ppp_link *const link =
1784 &priv->links[priv->activeLinks[sortByLatency[i]]];
1785
1786 if (link->conf.bandwidth > fastLink->conf.bandwidth) {
1787 fast = i;
1788 fastLink = link;
1789 }
1790 }
1791 distrib[sortByLatency[fast]] += len - total;
1792 } else while (total > len) {
1793 struct ng_ppp_link *slowLink =
1794 &priv->links[priv->activeLinks[sortByLatency[0]]];
1795 int delta, slow = 0;
1796
1797 /* Find the slowest link that still has bytes to remove */
1798 for (i = 1; i < numFragments; i++) {
1799 struct ng_ppp_link *const link =
1800 &priv->links[priv->activeLinks[sortByLatency[i]]];
1801
1802 if (distrib[sortByLatency[slow]] == 0
1803 || (distrib[sortByLatency[i]] > 0
1804 && link->conf.bandwidth <
1805 slowLink->conf.bandwidth)) {
1806 slow = i;
1807 slowLink = link;
1808 }
1809 }
1810 delta = total - len;
1811 if (delta > distrib[sortByLatency[slow]])
1812 delta = distrib[sortByLatency[slow]];
1813 distrib[sortByLatency[slow]] -= delta;
1814 total -= delta;
1815 }
1816}
1817
1818/*
1819 * Compare two integers
1820 */
1821static int
1822ng_ppp_intcmp(const void *v1, const void *v2)
1823{
1824 const int index1 = *((const int *) v1);
1825 const int index2 = *((const int *) v2);
1826
1827 return compareLatencies[index1] - compareLatencies[index2];
1828}
1829
1830/*
1831 * Prepend a possibly compressed PPP protocol number in front of a frame
1832 */
1833static struct mbuf *
1834ng_ppp_addproto(struct mbuf *m, int proto, int compOK)
1835{
1836 if (compOK && PROT_COMPRESSABLE(proto)) {
1837 u_char pbyte = (u_char)proto;
1838
1839 return ng_ppp_prepend(m, &pbyte, 1);
1840 } else {
1841 u_int16_t pword = htons((u_int16_t)proto);
1842
1843 return ng_ppp_prepend(m, &pword, 2);
1844 }
1845}
1846
1847/*
1848 * Prepend some bytes to an mbuf
1849 */
1850static struct mbuf *
1851ng_ppp_prepend(struct mbuf *m, const void *buf, int len)
1852{
1853 M_PREPEND(m, len, M_NOWAIT);
1854 if (m == NULL || (m->m_len < len && (m = m_pullup(m, len)) == NULL))
1855 return (NULL);
1856 bcopy(buf, mtod(m, u_char *), len);
1857 return (m);
1858}
1859
1860/*
1861 * Update private information that is derived from other private information
1862 */
1863static void
1864ng_ppp_update(node_p node, int newConf)
1865{
1866 const priv_p priv = node->private;
1867 int i;
1868
1869 /* Update active status for VJ Compression */
1870 priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL
1871 && priv->hooks[HOOK_INDEX_VJC_COMP] != NULL
1872 && priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL
1873 && priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL;
1874
1875 /* Increase latency for each link an amount equal to one MP header */
1876 if (newConf) {
1877 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1878 int hdrBytes;
1879
1880 hdrBytes = (priv->links[i].conf.enableACFComp ? 0 : 2)
1881 + (priv->links[i].conf.enableProtoComp ? 1 : 2)
1882 + (priv->conf.xmitShortSeq ? 2 : 4);
1883 priv->links[i].conf.latency +=
1884 ((hdrBytes * priv->links[i].conf.bandwidth) + 50)
1885 / 100;
1886 }
1887 }
1888
1889 /* Update list of active links */
1890 bzero(&priv->activeLinks, sizeof(priv->activeLinks));
1891 priv->numActiveLinks = 0;
1892 priv->allLinksEqual = 1;
1893 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1894 struct ng_ppp_link *const link = &priv->links[i];
1895
1896 /* Is link active? */
1897 if (link->conf.enableLink && link->hook != NULL) {
1898 struct ng_ppp_link *link0;
1899
1900 /* Add link to list of active links */
1901 priv->activeLinks[priv->numActiveLinks++] = i;
1902 link0 = &priv->links[priv->activeLinks[0]];
1903
1904 /* Determine if all links are still equal */
1905 if (link->conf.latency != link0->conf.latency
1906 || link->conf.bandwidth != link0->conf.bandwidth)
1907 priv->allLinksEqual = 0;
1908
1909 /* Initialize rec'd sequence number */
1910 if (link->seq == MP_NOSEQ) {
1911 link->seq = (link == link0) ?
1912 MP_INITIAL_SEQ : link0->seq;
1913 }
1914 } else
1915 link->seq = MP_NOSEQ;
1916 }
1917
1918 /* Update MP state as multi-link is active or not */
1919 if (priv->conf.enableMultilink && priv->numActiveLinks > 0)
1920 ng_ppp_start_frag_timer(node);
1921 else {
1922 ng_ppp_stop_frag_timer(node);
1923 ng_ppp_frag_reset(node);
1924 priv->xseq = MP_INITIAL_SEQ;
1925 priv->mseq = MP_INITIAL_SEQ;
1926 for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
1927 struct ng_ppp_link *const link = &priv->links[i];
1928
1929 bzero(&link->lastWrite, sizeof(link->lastWrite));
1930 link->bytesInQueue = 0;
1931 link->seq = MP_NOSEQ;
1932 }
1933 }
1934}
1935
1936/*
1937 * Determine if a new configuration would represent a valid change
1938 * from the current configuration and link activity status.
1939 */
1940static int
1941ng_ppp_config_valid(node_p node, const struct ng_ppp_node_conf *newConf)
1942{
1943 const priv_p priv = node->private;
1944 int i, newNumLinksActive;
1945
1946 /* Check per-link config and count how many links would be active */
1947 for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) {
1948 if (newConf->links[i].enableLink && priv->links[i].hook != NULL)
1949 newNumLinksActive++;
1950 if (!newConf->links[i].enableLink)
1951 continue;
1952 if (newConf->links[i].mru < MP_MIN_LINK_MRU)
1953 return (0);
1954 if (newConf->links[i].bandwidth == 0)
1955 return (0);
1956 if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH)
1957 return (0);
1958 if (newConf->links[i].latency > NG_PPP_MAX_LATENCY)
1959 return (0);
1960 }
1961
1962 /* Check bundle parameters */
1963 if (newConf->bund.enableMultilink && newConf->bund.mrru < MP_MIN_MRRU)
1964 return (0);
1965
1966 /* Disallow changes to multi-link configuration while MP is active */
1967 if (priv->numActiveLinks > 0 && newNumLinksActive > 0) {
1968 if (!priv->conf.enableMultilink
1969 != !newConf->bund.enableMultilink
1970 || !priv->conf.xmitShortSeq != !newConf->bund.xmitShortSeq
1971 || !priv->conf.recvShortSeq != !newConf->bund.recvShortSeq)
1972 return (0);
1973 }
1974
1975 /* At most one link can be active unless multi-link is enabled */
1976 if (!newConf->bund.enableMultilink && newNumLinksActive > 1)
1977 return (0);
1978
1979 /* Configuration change would be valid */
1980 return (1);
1981}
1982
1983/*
1984 * Free all entries in the fragment queue
1985 */
1986static void
1987ng_ppp_frag_reset(node_p node)
1988{
1989 const priv_p priv = node->private;
1990 struct ng_ppp_frag *qent, *qnext;
1991
1992 for (qent = TAILQ_FIRST(&priv->frags); qent; qent = qnext) {
1993 qnext = TAILQ_NEXT(qent, f_qent);
1994 NG_FREE_DATA(qent->data, qent->meta);
1995 FREE(qent, M_NETGRAPH);
1996 }
1997 TAILQ_INIT(&priv->frags);
1998 priv->qlen = 0;
1999}
2000
2001/*
2002 * Start fragment queue timer
2003 */
2004static void
2005ng_ppp_start_frag_timer(node_p node)
2006{
2007 const priv_p priv = node->private;
2008
2009 if (!priv->timerActive) {
2010 priv->fragTimer = timeout(ng_ppp_frag_timeout,
2011 node, MP_FRAGTIMER_INTERVAL);
2012 priv->timerActive = 1;
2013 node->refs++;
2014 }
2015}
2016
2017/*
2018 * Stop fragment queue timer
2019 */
2020static void
2021ng_ppp_stop_frag_timer(node_p node)
2022{
2023 const priv_p priv = node->private;
2024
2025 if (priv->timerActive) {
2026 untimeout(ng_ppp_frag_timeout, node, priv->fragTimer);
2027 priv->timerActive = 0;
2028 KASSERT(node->refs > 1,
2029 ("%s: refs=%d", __FUNCTION__, node->refs));
2030 ng_unref(node);
2031 }
2032}
2033
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