1 /* udp_usrreq.c 4.19 82/01/19 */ 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_off > MMAXOFF || m->m_len < sizeof (struct udpiphdr)) && 46 (m = m_pullup(m, sizeof (struct udpiphdr))) == 0) { 47 udpstat.udps_hdrops++; 48 return; 49 } 50 ui = mtod(m, struct udpiphdr *); 51 if (((struct ip *)ui)->ip_hl > (sizeof (struct ip) >> 2)) 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 udp_output(inp, m0) 117 struct inpcb *inp; 118 struct mbuf *m0; 119 { 120 register struct mbuf *m; 121 register struct udpiphdr *ui; 122 register int len = 0; 123 124 COUNT(UDP_OUTPUT); 125 /* 126 * Calculate data length and get a mbuf 127 * for UDP and IP headers. 128 */ 129 for (m = m0; m; m = m->m_next) 130 len += m->m_len; 131 m = m_get(M_DONTWAIT); 132 if (m == 0) 133 goto bad; 134 135 /* 136 * Fill in mbuf with extended UDP header 137 * and addresses and length put into network format. 138 */ 139 m->m_off = MMAXOFF - sizeof (struct udpiphdr); 140 m->m_len = sizeof (struct udpiphdr); 141 m->m_next = m0; 142 ui = mtod(m, struct udpiphdr *); 143 ui->ui_next = ui->ui_prev = 0; 144 ui->ui_x1 = 0; 145 ui->ui_pr = IPPROTO_UDP; 146 ui->ui_len = sizeof (struct udpiphdr) + len; 147 ui->ui_src = inp->inp_laddr; 148 ui->ui_dst = inp->inp_faddr; 149 ui->ui_sport = inp->inp_lport; 150 ui->ui_dport = inp->inp_fport; 151 ui->ui_ulen = htons((u_short)len); 152 153 /* 154 * Stuff checksum and output datagram. 155 */ 156 ui->ui_sum = 0; 157 ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len); 158 ((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len; 159 ((struct ip *)ui)->ip_ttl = MAXTTL; 160 (void) ip_output(m, (struct mbuf *)0); 161 return; 162 bad: 163 m_freem(m); 164 } 165 166 udp_usrreq(so, req, m, addr) 167 struct socket *so; 168 int req; 169 struct mbuf *m; 170 caddr_t addr; 171 { 172 struct inpcb *inp = sotoinpcb(so); 173 int error; 174 175 COUNT(UDP_USRREQ); 176 if (inp == 0 && req != PRU_ATTACH) 177 return (EINVAL); 178 switch (req) { 179 180 case PRU_ATTACH: 181 if (inp != 0) 182 return (EINVAL); 183 error = in_pcbattach(so, &udb, 2048, 2048, (struct sockaddr_in *)addr); 184 if (error) 185 return (error); 186 break; 187 188 case PRU_DETACH: 189 if (inp == 0) 190 return (ENOTCONN); 191 in_pcbdetach(inp); 192 break; 193 194 case PRU_CONNECT: 195 if (inp->inp_faddr.s_addr) 196 return (EISCONN); 197 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 198 if (error) 199 return (error); 200 soisconnected(so); 201 break; 202 203 case PRU_ACCEPT: 204 return (EOPNOTSUPP); 205 206 case PRU_DISCONNECT: 207 if (inp->inp_faddr.s_addr == 0) 208 return (ENOTCONN); 209 in_pcbdisconnect(inp); 210 soisdisconnected(so); 211 break; 212 213 case PRU_SHUTDOWN: 214 socantsendmore(so); 215 break; 216 217 case PRU_SEND: 218 if (addr) { 219 if (inp->inp_faddr.s_addr) 220 return (EISCONN); 221 error = in_pcbconnect(inp, (struct sockaddr_in *)addr); 222 if (error) 223 return (error); 224 } else { 225 if (inp->inp_faddr.s_addr == 0) 226 return (ENOTCONN); 227 } 228 udp_output(inp, m); 229 if (addr) 230 in_pcbdisconnect(inp); 231 break; 232 233 case PRU_ABORT: 234 in_pcbdetach(inp); 235 sofree(so); 236 soisdisconnected(so); 237 break; 238 239 case PRU_CONTROL: 240 return (EOPNOTSUPP); 241 242 default: 243 panic("udp_usrreq"); 244 } 245 return (0); 246 } 247