1 /* udp_usrreq.c 4.42 83/01/04 */ 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 "../netinet/in.h" 11 #include "../net/if.h" 12 #include "../net/route.h" 13 #include "../netinet/in_pcb.h" 14 #include "../netinet/in_systm.h" 15 #include "../netinet/ip.h" 16 #include "../netinet/ip_var.h" 17 #include "../netinet/ip_icmp.h" 18 #include "../netinet/udp.h" 19 #include "../netinet/udp_var.h" 20 #include <errno.h> 21 22 /* 23 * UDP protocol implementation. 24 * Per RFC 768, August, 1980. 25 */ 26 udp_init() 27 { 28 29 udb.inp_next = udb.inp_prev = &udb; 30 } 31 32 int udpcksum; 33 struct sockaddr_in udp_in = { AF_INET }; 34 35 udp_input(m0) 36 struct mbuf *m0; 37 { 38 register struct udpiphdr *ui; 39 register struct inpcb *inp; 40 register struct mbuf *m; 41 int len; 42 43 /* 44 * Get IP and UDP header together in first mbuf. 45 */ 46 m = m0; 47 if ((m->m_off > MMAXOFF || m->m_len < sizeof (struct udpiphdr)) && 48 (m = m_pullup(m, sizeof (struct udpiphdr))) == 0) { 49 udpstat.udps_hdrops++; 50 return; 51 } 52 ui = mtod(m, struct udpiphdr *); 53 if (((struct ip *)ui)->ip_hl > (sizeof (struct ip) >> 2)) 54 ip_stripoptions((struct ip *)ui, (struct mbuf *)0); 55 56 /* 57 * Make mbuf data length reflect UDP length. 58 * If not enough data to reflect UDP length, drop. 59 */ 60 len = ntohs((u_short)ui->ui_ulen); 61 if (((struct ip *)ui)->ip_len != len) { 62 if (len > ((struct ip *)ui)->ip_len) { 63 udpstat.udps_badlen++; 64 goto bad; 65 } 66 m_adj(m, ((struct ip *)ui)->ip_len - len); 67 /* (struct ip *)ui->ip_len = len; */ 68 } 69 70 /* 71 * Checksum extended UDP header and data. 72 */ 73 if (udpcksum) { 74 ui->ui_next = ui->ui_prev = 0; 75 ui->ui_x1 = 0; 76 ui->ui_len = htons((u_short)len); 77 if (ui->ui_sum = in_cksum(m, len + sizeof (struct ip))) { 78 udpstat.udps_badsum++; 79 printf("udp cksum %x\n", ui->ui_sum); 80 m_freem(m); 81 return; 82 } 83 } 84 85 /* 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 INPLOOKUP_WILDCARD); 91 if (inp == 0) { 92 /* don't send ICMP response for broadcast packet */ 93 if (in_lnaof(ui->ui_dst) == INADDR_ANY) 94 goto bad; 95 icmp_error((struct ip *)ui, ICMP_UNREACH, ICMP_UNREACH_PORT); 96 return; 97 } 98 99 /* 100 * Construct sockaddr format source address. 101 * Stuff source address and datagram in user buffer. 102 */ 103 udp_in.sin_port = ui->ui_sport; 104 udp_in.sin_addr = ui->ui_src; 105 m->m_len -= sizeof (struct udpiphdr); 106 m->m_off += sizeof (struct udpiphdr); 107 if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, m) == 0) 108 goto bad; 109 sorwakeup(inp->inp_socket); 110 return; 111 bad: 112 m_freem(m); 113 } 114 115 udp_abort(inp) 116 struct inpcb *inp; 117 { 118 struct socket *so = inp->inp_socket; 119 120 in_pcbdisconnect(inp); 121 soisdisconnected(so); 122 } 123 124 udp_ctlinput(cmd, arg) 125 int cmd; 126 caddr_t arg; 127 { 128 struct in_addr *sin; 129 extern u_char inetctlerrmap[]; 130 131 if (cmd < 0 || cmd > PRC_NCMDS) 132 return; 133 switch (cmd) { 134 135 case PRC_ROUTEDEAD: 136 break; 137 138 case PRC_QUENCH: 139 break; 140 141 /* these are handled by ip */ 142 case PRC_IFDOWN: 143 case PRC_HOSTDEAD: 144 case PRC_HOSTUNREACH: 145 break; 146 147 default: 148 sin = &((struct icmp *)arg)->icmp_ip.ip_dst; 149 in_pcbnotify(&udb, sin, (int)inetctlerrmap[cmd], udp_abort); 150 } 151 } 152 153 udp_output(inp, m0) 154 struct inpcb *inp; 155 struct mbuf *m0; 156 { 157 register struct mbuf *m; 158 register struct udpiphdr *ui; 159 register struct socket *so; 160 register int len = 0; 161 162 /* 163 * Calculate data length and get a mbuf 164 * for UDP and IP headers. 165 */ 166 for (m = m0; m; m = m->m_next) 167 len += m->m_len; 168 m = m_get(M_DONTWAIT, MT_HEADER); 169 if (m == 0) { 170 m_freem(m0); 171 return (ENOBUFS); 172 } 173 174 /* 175 * Fill in mbuf with extended UDP header 176 * and addresses and length put into network format. 177 */ 178 m->m_off = MMAXOFF - sizeof (struct udpiphdr); 179 m->m_len = sizeof (struct udpiphdr); 180 m->m_next = m0; 181 ui = mtod(m, struct udpiphdr *); 182 ui->ui_next = ui->ui_prev = 0; 183 ui->ui_x1 = 0; 184 ui->ui_pr = IPPROTO_UDP; 185 ui->ui_len = len + sizeof (struct udphdr); 186 ui->ui_src = inp->inp_laddr; 187 ui->ui_dst = inp->inp_faddr; 188 ui->ui_sport = inp->inp_lport; 189 ui->ui_dport = inp->inp_fport; 190 ui->ui_ulen = htons((u_short)ui->ui_len); 191 192 /* 193 * Stuff checksum and output datagram. 194 */ 195 ui->ui_sum = 0; 196 ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len); 197 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 198 ((struct ip *)ui)->ip_ttl = MAXTTL; 199 so = inp->inp_socket; 200 return (ip_output(m, (struct mbuf *)0, 201 (so->so_options & SO_DONTROUTE) ? &routetoif : (struct route *)0, 202 so->so_state & SS_PRIV)); 203 } 204 205 /*ARGSUSED*/ 206 udp_usrreq(so, req, m, nam, opt) 207 struct socket *so; 208 int req; 209 struct mbuf *m, *nam; 210 struct socketopt *opt; 211 { 212 struct inpcb *inp = sotoinpcb(so); 213 int error = 0; 214 215 if (inp == 0 && req != PRU_ATTACH) 216 return (EINVAL); 217 switch (req) { 218 219 case PRU_ATTACH: 220 if (inp != 0) 221 return (EINVAL); 222 error = in_pcballoc(so, &udb); 223 if (error) 224 break; 225 error = soreserve(so, 2048, 2048); 226 if (error) 227 break; 228 break; 229 230 case PRU_DETACH: 231 if (inp == 0) 232 return (ENOTCONN); 233 in_pcbdetach(inp); 234 break; 235 236 case PRU_BIND: 237 error = in_pcbbind(inp, nam); 238 break; 239 240 case PRU_LISTEN: 241 error = EOPNOTSUPP; 242 break; 243 244 case PRU_CONNECT: 245 if (inp->inp_faddr.s_addr != INADDR_ANY) 246 return (EISCONN); 247 error = in_pcbconnect(inp, nam); 248 if (error == 0) 249 soisconnected(so); 250 break; 251 252 case PRU_ACCEPT: 253 return (EOPNOTSUPP); 254 255 case PRU_DISCONNECT: 256 if (inp->inp_faddr.s_addr == INADDR_ANY) 257 return (ENOTCONN); 258 in_pcbdisconnect(inp); 259 soisdisconnected(so); 260 break; 261 262 case PRU_SHUTDOWN: 263 socantsendmore(so); 264 break; 265 266 case PRU_SEND: { 267 struct in_addr laddr; 268 269 if (nam) { 270 laddr = inp->inp_laddr; 271 if (inp->inp_faddr.s_addr != INADDR_ANY) 272 return (EISCONN); 273 error = in_pcbconnect(inp, nam); 274 if (error) 275 break; 276 } else { 277 if (inp->inp_faddr.s_addr == INADDR_ANY) 278 return (ENOTCONN); 279 } 280 error = udp_output(inp, m); 281 if (nam) { 282 in_pcbdisconnect(inp); 283 inp->inp_laddr = laddr; 284 } 285 } 286 break; 287 288 case PRU_ABORT: 289 in_pcbdetach(inp); 290 sofree(so); 291 soisdisconnected(so); 292 break; 293 294 case PRU_CONTROL: 295 return (EOPNOTSUPP); 296 297 case PRU_SOCKADDR: 298 in_setsockaddr(inp, nam); 299 break; 300 301 default: 302 panic("udp_usrreq"); 303 } 304 return (error); 305 } 306