xref: /csrg-svn/sys/netinet/udp_usrreq.c (revision 5166)
1 /*	udp_usrreq.c	4.13	81/12/02	*/
2 
3 #include "../h/param.h"
4 #include "../h/dir.h"
5 #include "../h/user.h"
6 #include "../h/mbuf.h"
7 #include "../h/protosw.h"
8 #include "../h/socket.h"
9 #include "../h/socketvar.h"
10 #include "../net/in.h"
11 #include "../net/in_pcb.h"
12 #include "../net/in_systm.h"
13 #include "../net/ip.h"
14 #include "../net/ip_var.h"
15 #include "../net/udp.h"
16 #include "../net/udp_var.h"
17 
18 /*
19  * UDP protocol implementation.
20  * Per RFC 768, August, 1980.
21  */
22 udp_init()
23 {
24 
25 COUNT(UDP_INIT);
26 	udb.inp_next = udb.inp_prev = &udb;
27 }
28 
29 int	udpcksum;
30 struct	sockaddr_in udp_in = { AF_INET };
31 
32 udp_input(m0)
33 	struct mbuf *m0;
34 {
35 	register struct udpiphdr *ui;
36 	register struct inpcb *inp;
37 	register struct mbuf *m;
38 	int len, ulen;
39 
40 COUNT(UDP_INPUT);
41 	/*
42 	 * Get ip and udp header together in first mbuf.
43 	 */
44 	m = m0;
45 	if (m->m_len < sizeof (struct udpiphdr) &&
46 	    m_pullup(m, sizeof (struct udpiphdr)) == 0) {
47 		udpstat.udps_hdrops++;
48 		goto bad;
49 	}
50 	ui = mtod(m, struct udpiphdr *);
51 	if (ui->ui_len > sizeof (struct ip))
52 		ip_stripoptions((struct ip *)ui, (char *)0);
53 
54 	/*
55 	 * Make mbuf data length reflect udp length.
56 	 * If not enough data to reflect udp length, drop.
57 	 */
58 	ulen = ntohs((u_short)ui->ui_ulen);
59 	len = sizeof (struct udpiphdr) + ulen;
60 	if (((struct ip *)ui)->ip_len != len) {
61 		if (len > ((struct ip *)ui)->ip_len) {
62 			udpstat.udps_badlen++;
63 			goto bad;
64 		}
65 		m_adj(m, ((struct ip *)ui)->ip_len - len);
66 		/* (struct ip *)ui->ip_len = len; */
67 	}
68 
69 	/*
70 	 * Checksum extended udp header and data.
71 	 */
72 	if (udpcksum) {
73 		ui->ui_next = ui->ui_prev = 0;
74 		ui->ui_x1 = 0;
75 		ui->ui_len = htons((u_short)(sizeof (struct udpiphdr) + ulen));
76 		if ((ui->ui_sum = in_cksum(m, len)) != 0xffff) {
77 			udpstat.udps_badsum++;
78 			printf("udp cksum %x\n", ui->ui_sum);
79 			m_freem(m);
80 			return;
81 		}
82 	}
83 
84 	/*
85 	 * Convert addresses and ports to host format.
86 	 * Locate pcb for datagram.
87 	 */
88 	inp = in_pcblookup(&udb,
89 	    ui->ui_src, ui->ui_sport, ui->ui_dst, ui->ui_dport);
90 	if (inp == 0)
91 		goto bad;
92 
93 	/*
94 	 * Construct sockaddr format source address.
95 	 * Stuff source address and datagram in user buffer.
96 	 */
97 	udp_in.sin_port = ui->ui_sport;
98 	udp_in.sin_addr = ui->ui_src;
99 	m->m_len -= sizeof (struct udpiphdr);
100 	m->m_off += sizeof (struct udpiphdr);
101 	if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, m) == 0)
102 		goto bad;
103 	sorwakeup(inp->inp_socket);
104 	return;
105 bad:
106 	m_freem(m);
107 }
108 
109 udp_ctlinput(m)
110 	struct mbuf *m;
111 {
112 
113 COUNT(UDP_CTLINPUT);
114 	printf("udp_ctlinput\n");
115 	m_freem(m);
116 }
117 
118 /*ARGSUSED*/
119 udp_output(inp, m0)
120 	struct inpcb *inp;
121 	struct mbuf *m0;
122 {
123 	register struct mbuf *m;
124 	register struct udpiphdr *ui;
125 	register int len = 0;
126 
127 COUNT(UDP_OUTPUT);
128 	/*
129 	 * Calculate data length and get a mbuf
130 	 * for udp and ip headers.
131 	 */
132 	for (m = m0; m; m = m->m_next)
133 		len += m->m_len;
134 	m = m_get(0);
135 	if (m == 0)
136 		goto bad;
137 
138 	/*
139 	 * Fill in mbuf with extended udp header
140 	 * and addresses and length put into network format.
141 	 */
142 	m->m_off = MMAXOFF - sizeof (struct udpiphdr);
143 	m->m_len = sizeof (struct udpiphdr);
144 	m->m_next = m0;
145 	ui = mtod(m, struct udpiphdr *);
146 	ui->ui_next = ui->ui_prev = 0;
147 	ui->ui_x1 = 0;
148 	ui->ui_pr = IPPROTO_UDP;
149 	ui->ui_len = sizeof (struct udpiphdr) + len;
150 	ui->ui_src = inp->inp_laddr;
151 	ui->ui_dst = inp->inp_faddr;
152 	ui->ui_sport = inp->inp_lport;
153 	ui->ui_dport = inp->inp_fport;
154 	ui->ui_ulen = htons((u_short)len);
155 
156 	/*
157 	 * Stuff checksum and output datagram.
158 	 */
159 	ui->ui_sum = 0;
160 	ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len);
161 	((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
162 	((struct ip *)ui)->ip_ttl = MAXTTL;
163 	(void) ip_output(m, (struct mbuf *)0);
164 	return;
165 bad:
166 	m_freem(m);
167 }
168 
169 /*ARGSUSED*/
170 udp_usrreq(so, req, m, addr)
171 	struct socket *so;
172 	int req;
173 	struct mbuf *m;
174 	caddr_t addr;
175 {
176 	struct inpcb *inp = sotoinpcb(so);
177 	int error;
178 
179 COUNT(UDP_USRREQ);
180 	if (inp == 0 && req != PRU_ATTACH)
181 		return (EINVAL);
182 	switch (req) {
183 
184 	case PRU_ATTACH:
185 		if (inp != 0)
186 			return (EINVAL);
187 		error = in_pcbattach(so, &udb, 2048, 2048, (struct sockaddr_in *)addr);
188 		if (error)
189 			return (error);
190 		break;
191 
192 	case PRU_DETACH:
193 		if (inp == 0)
194 			return (ENOTCONN);
195 		in_pcbdetach(inp);
196 		break;
197 
198 	case PRU_CONNECT:
199 		if (inp->inp_faddr.s_addr)
200 			return (EISCONN);
201 		error = in_pcbconnect(inp, (struct sockaddr_in *)addr);
202 		if (error)
203 			return (error);
204 		soisconnected(so);
205 		break;
206 
207 	case PRU_ACCEPT:
208 		return (EOPNOTSUPP);
209 
210 	case PRU_DISCONNECT:
211 		if (inp->inp_faddr.s_addr == 0)
212 			return (ENOTCONN);
213 		in_pcbdisconnect(inp);
214 		soisdisconnected(so);
215 		break;
216 
217 	case PRU_SHUTDOWN:
218 		socantsendmore(so);
219 		break;
220 
221 	case PRU_SEND:
222 		if (addr) {
223 			if (inp->inp_faddr.s_addr)
224 				return (EISCONN);
225 			error = in_pcbconnect(inp, (struct sockaddr_in *)addr);
226 			if (error)
227 				return (error);
228 		} else {
229 			if (inp->inp_faddr.s_addr == 0)
230 				return (ENOTCONN);
231 		}
232 		udp_output(inp, m);
233 		if (addr)
234 			in_pcbdisconnect(inp);
235 		break;
236 
237 	case PRU_ABORT:
238 		in_pcbdetach(inp);
239 		sofree(so);
240 		soisdisconnected(so);
241 		break;
242 
243 	case PRU_CONTROL:
244 		return (EOPNOTSUPP);
245 
246 	default:
247 		panic("udp_usrreq");
248 	}
249 	return (0);
250 }
251 
252 /*ARGSUSED*/
253 udp_sense(m)
254 	struct mbuf *m;
255 {
256 
257 COUNT(UDP_SENSE);
258 	printf("udp_sense\n");
259 	return (EOPNOTSUPP);
260 }
261