1 /* udp_usrreq.c 4.16 81/12/09 */ 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, (struct mbuf *)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 udphdr) + 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 udphdr) + ulen)); 76 if (ui->ui_sum = in_cksum(m, len)) { 77 udpstat.udps_badsum++; 78 printf("udp cksum %x\n", ui->ui_sum); 79 m_freem(m); 80 return; 81 } 82 } 83 84 /* 85 * Locate pcb for datagram. 86 */ 87 inp = in_pcblookup(&udb, 88 ui->ui_src, ui->ui_sport, ui->ui_dst, ui->ui_dport); 89 if (inp == 0) 90 goto bad; 91 92 /* 93 * Construct sockaddr format source address. 94 * Stuff source address and datagram in user buffer. 95 */ 96 udp_in.sin_port = ui->ui_sport; 97 udp_in.sin_addr = ui->ui_src; 98 m->m_len -= sizeof (struct udpiphdr); 99 m->m_off += sizeof (struct udpiphdr); 100 if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in, m) == 0) 101 goto bad; 102 sorwakeup(inp->inp_socket); 103 return; 104 bad: 105 m_freem(m); 106 } 107 108 udp_ctlinput(m) 109 struct mbuf *m; 110 { 111 112 COUNT(UDP_CTLINPUT); 113 m_freem(m); 114 } 115 116 /*ARGSUSED*/ 117 udp_output(inp, m0) 118 struct inpcb *inp; 119 struct mbuf *m0; 120 { 121 register struct mbuf *m; 122 register struct udpiphdr *ui; 123 register int len = 0; 124 125 COUNT(UDP_OUTPUT); 126 /* 127 * Calculate data length and get a mbuf 128 * for udp and ip headers. 129 */ 130 for (m = m0; m; m = m->m_next) 131 len += m->m_len; 132 m = m_get(0); 133 if (m == 0) 134 goto bad; 135 136 /* 137 * Fill in mbuf with extended udp header 138 * and addresses and length put into network format. 139 */ 140 m->m_off = MMAXOFF - sizeof (struct udpiphdr); 141 m->m_len = sizeof (struct udpiphdr); 142 m->m_next = m0; 143 ui = mtod(m, struct udpiphdr *); 144 ui->ui_next = ui->ui_prev = 0; 145 ui->ui_x1 = 0; 146 ui->ui_pr = IPPROTO_UDP; 147 ui->ui_len = sizeof (struct udpiphdr) + len; 148 ui->ui_src = inp->inp_laddr; 149 ui->ui_dst = inp->inp_faddr; 150 ui->ui_sport = inp->inp_lport; 151 ui->ui_dport = inp->inp_fport; 152 ui->ui_ulen = htons((u_short)len); 153 154 /* 155 * Stuff checksum and output datagram. 156 */ 157 ui->ui_sum = 0; 158 ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len); 159 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 160 ((struct ip *)ui)->ip_ttl = MAXTTL; 161 (void) ip_output(m, (struct mbuf *)0); 162 return; 163 bad: 164 m_freem(m); 165 } 166 167 /*ARGSUSED*/ 168 udp_usrreq(so, req, m, addr) 169 struct socket *so; 170 int req; 171 struct mbuf *m; 172 caddr_t addr; 173 { 174 struct inpcb *inp = sotoinpcb(so); 175 int error; 176 177 COUNT(UDP_USRREQ); 178 if (inp == 0 && req != PRU_ATTACH) 179 return (EINVAL); 180 switch (req) { 181 182 case PRU_ATTACH: 183 if (inp != 0) 184 return (EINVAL); 185 error = in_pcbattach(so, &udb, 2048, 2048, (struct sockaddr_in *)addr); 186 if (error) 187 return (error); 188 break; 189 190 case PRU_DETACH: 191 if (inp == 0) 192 return (ENOTCONN); 193 in_pcbdetach(inp); 194 break; 195 196 case PRU_CONNECT: 197 if (inp->inp_faddr.s_addr) 198 return (EISCONN); 199 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 200 if (error) 201 return (error); 202 soisconnected(so); 203 break; 204 205 case PRU_ACCEPT: 206 return (EOPNOTSUPP); 207 208 case PRU_DISCONNECT: 209 if (inp->inp_faddr.s_addr == 0) 210 return (ENOTCONN); 211 in_pcbdisconnect(inp); 212 soisdisconnected(so); 213 break; 214 215 case PRU_SHUTDOWN: 216 socantsendmore(so); 217 break; 218 219 case PRU_SEND: 220 if (addr) { 221 if (inp->inp_faddr.s_addr) 222 return (EISCONN); 223 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 224 if (error) 225 return (error); 226 } else { 227 if (inp->inp_faddr.s_addr == 0) 228 return (ENOTCONN); 229 } 230 udp_output(inp, m); 231 if (addr) 232 in_pcbdisconnect(inp); 233 break; 234 235 case PRU_ABORT: 236 in_pcbdetach(inp); 237 sofree(so); 238 soisdisconnected(so); 239 break; 240 241 case PRU_CONTROL: 242 return (EOPNOTSUPP); 243 244 default: 245 panic("udp_usrreq"); 246 } 247 return (0); 248 } 249