xref: /csrg-svn/sys/netiso/tuba_subr.c (revision 56565)
1 /*
2  * Copyright (c) 1992 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)tuba_subr.c	7.4 (Berkeley) 10/15/92
8  */
9 
10 #include <sys/param.h>
11 #include <sys/proc.h>
12 #include <sys/systm.h>
13 #include <sys/malloc.h>
14 #include <sys/mbuf.h>
15 #include <sys/socket.h>
16 #include <sys/socketvar.h>
17 #include <sys/protosw.h>
18 #include <sys/errno.h>
19 
20 #include <net/route.h>
21 #include <net/if.h>
22 
23 #include <netinet/in.h>
24 #include <netinet/in_systm.h>
25 #include <netinet/ip.h>
26 #include <netinet/in_pcb.h>
27 #include <netinet/ip_var.h>
28 #include <netinet/ip_icmp.h>
29 #include <netinet/tcp.h>
30 #include <netinet/tcp_fsm.h>
31 #include <netinet/tcp_seq.h>
32 #include <netinet/tcp_timer.h>
33 #include <netinet/tcp_var.h>
34 #include <netinet/tcpip.h>
35 #include <netinet/tcp_debug.h>
36 
37 #include <netiso/argo_debug.h>
38 #include <netiso/iso.h>
39 #include <netiso/clnp.h>
40 #include <netiso/iso_pcb.h>
41 #include <netiso/iso_var.h>
42 #include <netiso/tuba_addr.h>
43 
44 static struct	sockaddr_iso null_siso = { sizeof(null_siso), AF_ISO, };
45 extern struct	isopcb tuba_isopcb;
46 extern int	tuba_table_size;
47 extern int	tcppcbcachemiss, tcppredack, tcppreddat, tcprexmtthresh;
48 extern struct 	inpcb *tcp_last_inpcb;
49 extern struct	tcpiphdr tcp_saveti;
50 /*
51  * Tuba initialization
52  */
53 tuba_init()
54 {
55 #define TUBAHDRSIZE (3 /*LLC*/ + 9 /*CLNP Fixed*/ + 42 /*Addresses*/ \
56 		     + 6 /*CLNP Segment*/ + 20 /*TCP*/)
57 
58 	tuba_isopcb.isop_next = tuba_isopcb.isop_prev = &tuba_isopcb;
59 	tuba_isopcb.isop_faddr = &tuba_isopcb.isop_sfaddr;
60 	tuba_isopcb.isop_laddr = &tuba_isopcb.isop_sladdr;
61 	if (max_protohdr < TUBAHDRSIZE)
62 		max_protohdr = TUBAHDRSIZE;
63 	if (max_linkhdr + TUBAHDRSIZE > MHLEN)
64 		panic("tuba_init");
65 	tuba_table_init();
66 }
67 
68 static void
69 tuba_getaddr(error, sum, siso, index)
70 	int *error;
71 	u_long *sum;
72 	struct sockaddr_iso *siso;
73 	u_long index;
74 {
75 	register struct tuba_cache *tc;
76 	if (index < tuba_table_size && (tc = tuba_table[index])) {
77 		if (siso) {
78 			*siso = null_siso;
79 			siso->siso_addr = tc->tc_addr;
80 		}
81 		sum += tc->tc_sum_out;
82 	} else
83 		*error = 1;
84 }
85 
86 tuba_output(m, tp)
87 	register struct mbuf *m;
88 	struct tcpcb *tp;
89 {
90 	struct isopcb *isop;
91 	register struct tcpiphdr *n;
92 	u_long sum, i;
93 
94 	if (tp == 0 || (n = tp->t_template) == 0) {
95 		isop = &tuba_isopcb;
96 		i = sum = 0;
97 		n = mtod(m, struct tcpiphdr *);
98 		tuba_getaddr(&i, &sum, tuba_isopcb.isop_faddr,
99 				n->ti_dst.s_addr);
100 		tuba_getaddr(&i, &sum, tuba_isopcb.isop_laddr,
101 				n->ti_src.s_addr);
102 		goto adjust;
103 	}
104 	isop = (struct isopcb *)tp->t_tuba_pcb;
105 	if (n->ti_sum == 0) {
106 		i = sum = 0;
107 		tuba_getaddr(&i, &sum, (struct sockaddr_iso *)0,
108 				n->ti_dst.s_addr);
109 		tuba_getaddr(&i, &sum, (struct sockaddr_iso *)0,
110 				n->ti_src.s_addr);
111 		ICKSUM(sum, sum);
112 		n->ti_sum = sum;
113 		n = mtod(m, struct tcpiphdr *);
114 	adjust:
115 		if (i) {
116 			m_freem(m);
117 			return (ENOBUFS);
118 		}
119 		ICKSUM(n->ti_sum, sum + n->ti_sum);
120 	}
121 	m->m_len -= sizeof (struct ip);
122 	m->m_pkthdr.len -= sizeof (struct ip);
123 	m->m_data += sizeof (struct ip);
124 	return (clnp_output(m, isop, m->m_pkthdr.len, 0));
125 }
126 
127 tuba_refcnt(isop, delta)
128 	struct isopcb *isop;
129 {
130 	register struct tuba_cache *tc;
131 	unsigned index, sum;
132 
133 	if (delta != 1)
134 		delta = -1;
135 	if (isop == 0 || isop->isop_faddr == 0 || isop->isop_laddr == 0 ||
136 	    (delta == -1 && isop->isop_tuba_cached == 0) ||
137 	    (delta == 1 && isop->isop_tuba_cached != 0))
138 		return;
139 	isop->isop_tuba_cached = (delta == 1);
140 	if ((index = tuba_lookup(&isop->isop_sfaddr.siso_addr)) != 0 &&
141 	    (tc = tuba_table[index]) != 0 && (delta == 1 || tc->tc_refcnt > 0))
142 		tc->tc_refcnt += delta;
143 	if ((index = tuba_lookup(&isop->isop_sladdr.siso_addr)) != 0 &&
144 	    (tc = tuba_table[index]) != 0 && (delta == 1 || tc->tc_refcnt > 0))
145 		tc->tc_refcnt += delta;
146 }
147 
148 tuba_pcbdetach(isop)
149 	struct isopcb *isop;
150 {
151 	if (isop == 0)
152 		return;
153 	tuba_refcnt(isop, -1);
154 	isop->isop_socket = 0;
155 	iso_pcbdetach(isop);
156 }
157 
158 /*
159  * Avoid  in_pcbconnect in faked out tcp_input()
160  */
161 tuba_pcbconnect(inp, nam)
162 	register struct inpcb *inp;
163 	struct mbuf *nam;
164 {
165 	register struct sockaddr_iso *siso = mtod(nam, struct sockaddr_iso *);
166 	struct sockaddr_in *sin = mtod(nam, struct sockaddr_in *);
167 	struct tcpcb *tp = intotcpcb(inp);
168 	unsigned index = sin->sin_addr.s_addr;
169 	struct tuba_cache *tc = tuba_table[index];
170 	struct isopcb *isop = (struct isopcb *)tp->t_tuba_pcb;
171 	int error;
172 
173 	inp->inp_faddr.s_addr = index;
174 	inp->inp_fport = sin->sin_port;
175 	*siso = null_siso;
176 	siso->siso_addr = tc->tc_addr;
177 	siso->siso_tlen = sizeof(inp->inp_fport);
178 	bcopy((caddr_t)&inp->inp_fport, TSEL(siso), sizeof(inp->inp_fport));
179 	nam->m_len = sizeof(*siso);
180 	if ((error = iso_pcbconnect(isop, nam)) == 0)
181 		tuba_refcnt(isop, 1);
182 	return (error);
183 }
184 
185 /*
186  * CALLED FROM:
187  * 	clnp's input routine, indirectly through the protosw.
188  * FUNCTION and ARGUMENTS:
189  * Take a packet (m) from clnp, strip off the clnp header
190  * and do tcp input processing.
191  * No return value.
192  */
193 tuba_tcpinput(m, src, dst, clnp_len, ce_bit)
194 	register struct mbuf *m;
195 	struct sockaddr_iso *src, *dst;
196 	int clnp_len, ce_bit;
197 {
198 	int s = splnet();
199 	unsigned long fix_cksum, lindex, findex;
200 	register struct tcpiphdr *ti;
201 	register struct inpcb *inp;
202 	struct mbuf *om = 0;
203 	int len, tlen, off;
204 	register struct tcpcb *tp = 0;
205 	int tiflags;
206 	struct socket *so;
207 	int todrop, acked, ourfinisacked, needoutput = 0;
208 	short ostate;
209 	struct in_addr laddr;
210 	int dropsocket = 0, iss = 0;
211 
212 	if ((m->m_flags & M_PKTHDR) == 0)
213 		panic("tuba_input");
214 	/*
215 	 * Do some housekeeping looking up CLNP addresses.
216 	 * If we are out of space might as well drop the packet now.
217 	 */
218 	tcpstat.tcps_rcvtotal++;
219 	if ((lindex = tuba_lookup(&dst->siso_addr) == 0) ||
220 	    (findex = tuba_lookup(&dst->siso_addr) == 0))
221 		goto drop;
222 	/*
223 	 * Get CLNP and TCP header together in first mbuf.
224 	 * CLNP gave us an mbuf chain WITH the clnp header pulled up,
225 	 * and the length of the clnp header.
226 	 */
227 	len = clnp_len + sizeof(struct tcphdr);
228 	if (m->m_len < len) {
229 		if ((m = m_pullup(m, len)) == 0) {
230 			tcpstat.tcps_rcvshort++;
231 			return;
232 		}
233 	}
234 	/*
235 	 * Calculate checksum of extended TCP header and data,
236 	 * by adjusting the checksum for missing parts of the header.
237 	 */
238 	m->m_data += clnp_len;
239 	m->m_len -= clnp_len;
240 	tlen = m->m_pkthdr.len -= clnp_len;
241 	ICKSUM(fix_cksum, tuba_table[findex]->tc_sum_in + htons((u_short)tlen)
242 		+ tuba_table[lindex]->tc_sum_in + in_cksum(m, tlen));
243 	if (fix_cksum != 0xffff) {
244 		tcpstat.tcps_rcvbadsum++;
245 		goto drop;
246 	}
247 	m->m_data -= sizeof(struct ip);
248 	m->m_len += sizeof(struct ip);
249 	m->m_pkthdr.len += sizeof(struct ip);
250 	/*
251 	 * The reassembly code assumes it will be overwriting a useless
252 	 * part of the packet, which is why we need to have ti point
253 	 * into the packet itself.
254 	 *
255 	 * Check to see if the data is properly alligned
256 	 * so that we can save copying the tcp header.
257 	 * This code knows way too much about the structure of mbufs!
258 	 */
259 	off = ((sizeof (long) - 1) & ((m->m_flags & M_EXT) ?
260 		(m->m_data - m->m_ext.ext_buf) :  (m->m_data - m->m_pktdat)));
261 	if (off) {
262 		struct mbuf *m0 = m_gethdr(M_DONTWAIT, MT_DATA);
263 		if (m0 == 0) {
264 			goto drop;
265 		}
266 		bcopy(mtod(m, caddr_t) + sizeof(struct ip),
267 		      mtod(m0, caddr_t) + sizeof(struct ip),
268 		      sizeof(struct tcphdr));
269 		m->m_data += sizeof(struct tcpiphdr);
270 		m0->m_next = m;
271 		m0->m_pkthdr = m->m_pkthdr;
272 		m0->m_flags = m->m_flags & M_COPYFLAGS;
273 		m0->m_len = sizeof(struct tcpiphdr);
274 		m = m0;
275 	}
276 	ti = mtod(m, struct tcpiphdr *);
277 	ti->ti_src.s_addr = findex;
278 	ti->ti_dst.s_addr = lindex;
279 	ti->ti_len = tlen;
280 	/*
281 	 * Now include the rest of TCP input
282 	 */
283 #define TUBA_INCLUDE
284 #define in_pcbconnect	tuba_pcbconnect
285 
286 #include <netinet/tcp_input.c>
287 }
288