1 /* udp_usrreq.c 4.27 82/04/24 */ 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/if.h" 12 #include "../net/route.h" 13 #include "../net/in_pcb.h" 14 #include "../net/in_systm.h" 15 #include "../net/ip.h" 16 #include "../net/ip_var.h" 17 #include "../net/ip_icmp.h" 18 #include "../net/udp.h" 19 #include "../net/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 COUNT(UDP_INIT); 30 udb.inp_next = udb.inp_prev = &udb; 31 } 32 33 int udpcksum; 34 struct sockaddr_in udp_in = { AF_INET }; 35 36 udp_input(m0) 37 struct mbuf *m0; 38 { 39 register struct udpiphdr *ui; 40 register struct inpcb *inp; 41 register struct mbuf *m; 42 int len, ulen; 43 44 COUNT(UDP_INPUT); 45 /* 46 * Get IP and UDP header together in first mbuf. 47 */ 48 m = m0; 49 if ((m->m_off > MMAXOFF || m->m_len < sizeof (struct udpiphdr)) && 50 (m = m_pullup(m, sizeof (struct udpiphdr))) == 0) { 51 udpstat.udps_hdrops++; 52 return; 53 } 54 ui = mtod(m, struct udpiphdr *); 55 if (((struct ip *)ui)->ip_hl > (sizeof (struct ip) >> 2)) 56 ip_stripoptions((struct ip *)ui, (struct mbuf *)0); 57 58 /* 59 * Make mbuf data length reflect UDP length. 60 * If not enough data to reflect UDP length, drop. 61 */ 62 ulen = ntohs((u_short)ui->ui_ulen); 63 len = sizeof (struct udphdr) + ulen; 64 if (((struct ip *)ui)->ip_len != len) { 65 if (len > ((struct ip *)ui)->ip_len) { 66 udpstat.udps_badlen++; 67 goto bad; 68 } 69 m_adj(m, ((struct ip *)ui)->ip_len - len); 70 /* (struct ip *)ui->ip_len = len; */ 71 } 72 73 /* 74 * Checksum extended UDP header and data. 75 */ 76 if (udpcksum) { 77 ui->ui_next = ui->ui_prev = 0; 78 ui->ui_x1 = 0; 79 ui->ui_len = htons((u_short)(sizeof (struct udphdr) + ulen)); 80 if (ui->ui_sum = in_cksum(m, len)) { 81 udpstat.udps_badsum++; 82 printf("udp cksum %x\n", ui->ui_sum); 83 m_freem(m); 84 return; 85 } 86 } 87 88 /* 89 * Locate pcb for datagram. On wildcard match, update 90 * control block to anchor network and host address. 91 */ 92 inp = in_pcblookup(&udb, 93 ui->ui_src, ui->ui_sport, ui->ui_dst, ui->ui_dport, 94 INPLOOKUP_WILDCARD); 95 if (inp == 0) { 96 struct in_addr broadcastaddr; 97 98 broadcastaddr = if_makeaddr(ui->ui_dst.s_net, INADDR_ANY); 99 if (ui->ui_dst.s_addr != broadcastaddr.s_addr) 100 goto bad; 101 icmp_error((struct ip *)ui, ICMP_UNREACH, ICMP_UNREACH_PORT); 102 return; 103 } 104 105 /* 106 * Construct sockaddr format source address. 107 * Stuff source address and datagram in user buffer. 108 */ 109 udp_in.sin_port = ui->ui_sport; 110 udp_in.sin_addr = ui->ui_src; 111 m->m_len -= sizeof (struct udpiphdr); 112 m->m_off += sizeof (struct udpiphdr); 113 if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, m) == 0) 114 goto bad; 115 sorwakeup(inp->inp_socket); 116 return; 117 bad: 118 m_freem(m); 119 } 120 121 udp_ctlinput(cmd, arg) 122 int cmd; 123 caddr_t arg; 124 { 125 126 COUNT(UDP_CTLINPUT); 127 } 128 129 udp_abort(inp) 130 struct inpcb *inp; 131 { 132 struct socket *so = inp->inp_socket; 133 134 in_pcbdisconnect(inp); 135 soisdisconnected(so); 136 } 137 138 udp_output(inp, m0) 139 struct inpcb *inp; 140 struct mbuf *m0; 141 { 142 register struct mbuf *m; 143 register struct udpiphdr *ui; 144 register int len = 0; 145 146 COUNT(UDP_OUTPUT); 147 /* 148 * Calculate data length and get a mbuf 149 * for UDP and IP headers. 150 */ 151 for (m = m0; m; m = m->m_next) 152 len += m->m_len; 153 m = m_get(M_DONTWAIT); 154 if (m == 0) { 155 m_freem(m0); 156 return (ENOBUFS); 157 } 158 159 /* 160 * Fill in mbuf with extended UDP header 161 * and addresses and length put into network format. 162 */ 163 m->m_off = MMAXOFF - sizeof (struct udpiphdr); 164 m->m_len = sizeof (struct udpiphdr); 165 m->m_next = m0; 166 ui = mtod(m, struct udpiphdr *); 167 ui->ui_next = ui->ui_prev = 0; 168 ui->ui_x1 = 0; 169 ui->ui_pr = IPPROTO_UDP; 170 ui->ui_len = sizeof (struct udpiphdr) + len; 171 ui->ui_src = inp->inp_laddr; 172 ui->ui_dst = inp->inp_faddr; 173 ui->ui_sport = inp->inp_lport; 174 ui->ui_dport = inp->inp_fport; 175 ui->ui_ulen = htons((u_short)len); 176 177 /* 178 * Stuff checksum and output datagram. 179 */ 180 ui->ui_sum = 0; 181 ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len); 182 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 183 ((struct ip *)ui)->ip_ttl = MAXTTL; 184 return (ip_output(m, (struct mbuf *)0, 0, 185 inp->inp_socket->so_state & SS_PRIV)); 186 } 187 188 udp_usrreq(so, req, m, addr) 189 struct socket *so; 190 int req; 191 struct mbuf *m; 192 caddr_t addr; 193 { 194 struct inpcb *inp = sotoinpcb(so); 195 int error = 0; 196 197 COUNT(UDP_USRREQ); 198 if (inp == 0 && req != PRU_ATTACH) 199 return (EINVAL); 200 switch (req) { 201 202 case PRU_ATTACH: 203 if (inp != 0) 204 return (EINVAL); 205 error = in_pcbattach(so, &udb, 2048, 2048, 206 (struct sockaddr_in *)addr); 207 break; 208 209 case PRU_DETACH: 210 if (inp == 0) 211 return (ENOTCONN); 212 in_pcbdetach(inp); 213 break; 214 215 case PRU_CONNECT: 216 if (inp->inp_faddr.s_addr) 217 return (EISCONN); 218 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 219 if (error == 0) 220 soisconnected(so); 221 break; 222 223 case PRU_ACCEPT: 224 return (EOPNOTSUPP); 225 226 case PRU_DISCONNECT: 227 if (inp->inp_faddr.s_addr == 0) 228 return (ENOTCONN); 229 in_pcbdisconnect(inp); 230 soisdisconnected(so); 231 break; 232 233 case PRU_SHUTDOWN: 234 socantsendmore(so); 235 break; 236 237 case PRU_SEND: { 238 struct in_addr laddr; 239 240 if (addr) { 241 laddr = inp->inp_laddr; 242 if (inp->inp_faddr.s_addr) 243 return (EISCONN); 244 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 245 if (error) 246 break; 247 } else { 248 if (inp->inp_faddr.s_addr == 0) 249 return (ENOTCONN); 250 } 251 error = udp_output(inp, m); 252 if (addr) { 253 in_pcbdisconnect(inp); 254 inp->inp_laddr = laddr; 255 } 256 } 257 break; 258 259 case PRU_ABORT: 260 in_pcbdetach(inp); 261 sofree(so); 262 soisdisconnected(so); 263 break; 264 265 case PRU_CONTROL: 266 return (EOPNOTSUPP); 267 268 case PRU_SOCKADDR: 269 in_setsockaddr((struct sockaddr_in *)addr, inp); 270 break; 271 272 default: 273 panic("udp_usrreq"); 274 } 275 return (error); 276 } 277