1 | /* dhcpd 1.15 - Dynamic Host Configuration Protocol daemon.
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2 | * Author: Kees J. Bot
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3 | * 11 Jun 1999
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4 | */
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5 | #include <sys/types.h>
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6 | #include <stdio.h>
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7 | #include <stddef.h>
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8 | #include <stdlib.h>
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9 | #include <unistd.h>
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10 | #include <fcntl.h>
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11 | #include <errno.h>
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12 | #include <signal.h>
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13 | #include <string.h>
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14 | #include <time.h>
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15 | #include <limits.h>
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16 | #include <configfile.h>
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17 | #include <sys/ioctl.h>
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18 | #include <sys/asynchio.h>
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19 | #include <net/hton.h>
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20 | #include <net/gen/socket.h>
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21 | #include <net/gen/netdb.h>
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22 | #include <net/gen/in.h>
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23 | #include <net/gen/inet.h>
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24 | #include <net/gen/ether.h>
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25 | #include <net/gen/if_ether.h>
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26 | #include <net/gen/eth_hdr.h>
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27 | #include <net/gen/ip_hdr.h>
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28 | #include <net/gen/udp.h>
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29 | #include <net/gen/udp_hdr.h>
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30 | #include <net/gen/udp_io.h>
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31 | #include <net/gen/dhcp.h>
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32 | #include "arp.h"
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33 | #define EXTERN
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34 | #include "dhcpd.h"
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35 |
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36 | char *configfile= PATH_DHCPCONF;
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37 | char *poolfile= PATH_DHCPPOOL;
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38 | static char *cachefile= PATH_DHCPCACHE;
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39 | static int qflag; /* True if printing cached DHCP data. */
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40 | static int aflag, rflag; /* True if adding or deleting pool addresses. */
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41 |
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42 | #define BCAST_IP HTONL(0xFFFFFFFFUL)
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43 |
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44 | /* We try to play with up to this many networks. */
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45 | #define N_NETS 32
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46 | static unsigned n_nets; /* Actual number of networks. */
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47 |
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48 | void report(const char *label)
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49 | {
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50 | static FILE *logfp;
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51 | if(!logfp)
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52 | logfp = fopen("/usr/log/dhcp.log", "w");
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53 | if(logfp)
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54 | fprintf(logfp, "%s: %s: %s\n", program, label, strerror(errno));
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55 | }
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56 |
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57 | void fatal(const char *label)
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58 | {
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59 | report(label);
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60 | exit(1);
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61 | }
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62 |
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63 | void *allocate(size_t size)
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64 | {
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65 | void *mem;
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66 |
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67 | if ((mem= malloc(size)) == nil) fatal("Can't allocate memory");
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68 | return mem;
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69 | }
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70 |
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71 | /* Choose a DHCP xid based on the start time and network number. Not really
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72 | * random, but we don't have anything more random than the clock anyway.
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73 | */
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74 | #define XID(np) htonl(((u32_t) (np)->start << 8) | (np)->n)
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75 |
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76 | static network_t *network[N_NETS];
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77 |
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78 | int ifname2if(const char *name)
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79 | {
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80 | /* Translate an interface name to a number, -1 if bad. */
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81 | char *end;
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82 | unsigned long n;
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83 |
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84 | if (*name++ != 'i' || *name++ != 'p') return -1;
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85 | n= strtoul(name, &end, 10);
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86 | if (end == name || *end != 0) return -1;
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87 | if (n >= N_NETS) return -1;
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88 | return n;
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89 | }
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90 |
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91 | network_t *if2net(int n)
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92 | {
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93 | /* Translate an interface number to a network struct. */
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94 | int i;
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95 |
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96 | for (i= 0; i < n_nets; i++) {
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97 | if (network[i]->n == n) return network[i];
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98 | }
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99 | return nil;
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100 | }
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101 |
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102 | static ipaddr_t defaultmask(ipaddr_t ip)
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103 | {
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104 | /* Compute netmask by the oldfashioned Class rules. */
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105 | if (B(&ip)[0] < 0x80) return HTONL(0xFF000000UL); /* Class A. */
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106 | if (B(&ip)[0] < 0xC0) return HTONL(0xFFFF0000UL); /* Class B. */
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107 | if (B(&ip)[0] < 0xE0) return HTONL(0xFFFFFF00UL); /* Class C. */
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108 | return HTONL(0xFFFFFFFFUL); /* Multicast? Shouldn't happen... */
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109 | }
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110 |
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111 | #define POOL_MAGIC HTONL(0x81F85D00UL)
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112 |
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113 | typedef struct pool { /* Dynamic pool entry. */
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114 | u32_t magic; /* Pool file magic number. */
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115 | ipaddr_t ip; /* IP address. */
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116 | u32_t expire; /* When does/did the lease expire? */
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117 | u8_t len; /* Client ID length. */
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118 | u8_t unused[19]; /* Space for extensions. */
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119 | u8_t clid[CLID_MAX]; /* Client ID of current/last user. */
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120 | } pool_t;
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121 |
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122 | static int openpool(int mode)
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123 | {
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124 | /* Open the dynamic pool and lock it, return fd on success or -1. */
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125 | int fd;
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126 | struct flock lck;
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127 |
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128 | if ((fd= open(poolfile, mode, 0644)) < 0) {
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129 | if (errno != ENOENT) fatal(poolfile);
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130 | return -1;
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131 | }
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132 | if (mode != O_RDONLY) {
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133 | lck.l_type= F_WRLCK;
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134 | lck.l_whence= SEEK_SET;
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135 | lck.l_start= 0;
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136 | lck.l_len= 0;
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137 | if (fcntl(fd, F_SETLKW, &lck) < 0) fatal(poolfile);
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138 | }
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139 | return fd;
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140 | }
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141 |
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142 | static int readpool(int fd, pool_t *entry)
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143 | {
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144 | /* Read one pool table entry, return true unless EOF. */
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145 | ssize_t r;
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146 |
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147 | if ((r= read(fd, entry, sizeof(*entry))) < 0) fatal(poolfile);
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148 | if (r == 0) return 0;
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149 |
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150 | if (r != sizeof(*entry) || entry->magic != POOL_MAGIC) {
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151 | fprintf(stderr, "%s: %s: Pool table is corrupt\n",
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152 | program, poolfile);
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153 | close(fd);
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154 | return 0;
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155 | }
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156 | return 1;
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157 | }
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158 |
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159 | #if !__minix_vmd /* No fsync() for Minix. */
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160 | #define fsync(fd) sync()
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161 | #endif
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162 |
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163 | static void writepool(int fd, pool_t *entry)
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164 | {
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165 | /* (Over)write a pool table entry. */
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166 | if (write(fd, entry, sizeof(*entry)) < 0
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167 | || (entry->expire > now && fsync(fd) < 0)
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168 | ) {
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169 | fatal(poolfile);
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170 | }
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171 | }
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172 |
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173 | static ipaddr_t findpool(u8_t *client, size_t len, ipaddr_t ifip)
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174 | {
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175 | /* Look for a client ID in the dynamic address pool within the same network
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176 | * as 'ifip'. Select an unused one for a new client if necessary. Return
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177 | * 0 if nothing is available, otherwise the IP address we can offer.
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178 | */
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179 | int fd, found;
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180 | pool_t entry, oldest;
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181 | dhcp_t dhcp;
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182 | u8_t *pmask;
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183 | ipaddr_t mask;
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184 |
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185 | /* Any information available on the network the client is at? */
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186 | if (!makedhcp(&dhcp, nil, 0, nil, 0, ifip, ifip, nil)) return 0;
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187 |
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188 | if ((fd= openpool(O_RDWR)) < 0) return 0;
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189 |
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190 | (void) gettag(&dhcp, DHCP_TAG_NETMASK, &pmask, nil);
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191 | memcpy(&mask, pmask, sizeof(mask));
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192 |
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193 | oldest.expire= NEVER;
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194 | while ((found= readpool(fd, &entry))) {
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195 | /* Deleted entry? */
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196 | if (entry.ip == 0) continue;
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197 |
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198 | /* Correct network? */
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199 | if (((entry.ip ^ ifip) & mask) != 0) continue;
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200 |
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201 | /* Client present? */
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202 | if (entry.len == len && memcmp(entry.clid, client, len) == 0) break;
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203 |
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204 | /* Oldest candidate for a new lease? */
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205 | entry.expire= ntohl(entry.expire);
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206 | if (entry.expire < oldest.expire) oldest= entry;
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207 | }
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208 | close(fd);
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209 |
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210 | if (found) return entry.ip;
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211 | if (oldest.expire <= now) return oldest.ip;
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212 | return 0;
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213 | }
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214 |
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215 | static int commitpool(ipaddr_t ip, u8_t *client, size_t len, time_t expire)
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216 | {
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217 | /* Commit a new binding to stable storage, return true on success. */
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218 | int fd;
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219 | pool_t entry;
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220 |
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221 | if ((fd= openpool(O_RDWR)) < 0) return 0;
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222 |
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223 | do {
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224 | if (!readpool(fd, &entry)) {
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225 | close(fd);
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226 | return 0;
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227 | }
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228 | } while (entry.ip != ip);
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229 |
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230 | entry.expire= htonl(expire);
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231 | entry.len= len;
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232 | memcpy(entry.clid, client, len);
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233 | if (lseek(fd, -(off_t)sizeof(entry), SEEK_CUR) == -1) fatal(poolfile);
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234 | writepool(fd, &entry);
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235 | close(fd);
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236 | return 1;
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237 | }
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238 |
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239 | static void updatepool(int add, const char *name)
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240 | {
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241 | /* Add a new IP address to the dynamic pool. */
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242 | ipaddr_t ip;
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243 | int fd, i;
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244 | pool_t entry;
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245 | struct hostent *he;
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246 | off_t off, off0;
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247 |
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248 | if ((he= gethostbyname(name)) == nil || he->h_addrtype != AF_INET) {
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249 | fprintf(stderr, "%s: %s: Unknown host\n", program, name);
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250 | exit(1);
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251 | }
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252 | for (i= 0; he->h_addr_list[i] != nil; i++) {}
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253 | if (i != 1) {
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254 | fprintf(stderr, "%s: %s has %d addresses\n", program, name, i);
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255 | exit(1);
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256 | }
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257 | memcpy(&ip, he->h_addr_list[0], sizeof(ip));
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258 |
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259 | if ((fd= openpool(O_RDWR|O_CREAT)) < 0) fatal(poolfile);
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260 |
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261 | off= 0;
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262 | off0= -1;
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263 | while (readpool(fd, &entry)) {
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264 | if (add) {
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265 | if (entry.ip == ip) {
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266 | fprintf(stderr, "%s: %s: %s is already present\n",
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267 | program, poolfile, name);
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268 | exit(1);
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269 | }
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270 | if (entry.ip == 0 && off0 == -1) off0= off;
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271 | } else {
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272 | if (entry.ip == ip) {
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273 | memset(&entry, 0, sizeof(entry));
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274 | entry.magic= POOL_MAGIC;
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275 | entry.ip= 0;
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276 | if (lseek(fd, off, SEEK_SET) == -1) fatal(poolfile);
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277 | writepool(fd, &entry);
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278 | }
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279 | }
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280 | off+= sizeof(entry);
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281 | }
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282 |
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283 | if (add) {
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284 | if (off0 != -1 && lseek(fd, off0, SEEK_SET) == -1) fatal(poolfile);
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285 | memset(&entry, 0, sizeof(entry));
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286 | entry.magic= POOL_MAGIC;
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287 | entry.ip= ip;
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288 | writepool(fd, &entry);
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289 | }
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290 | close(fd);
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291 | }
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292 |
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293 | static void cachedhcp(int n, dhcp_t *dp)
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294 | {
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295 | /* Store a DHCP packet in a cache where those who care can find it. */
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296 | static int inited;
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297 | FILE *fp;
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298 | int fd;
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299 | int mode;
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300 |
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301 | if (test > 0) return;
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302 |
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303 | if (!inited) {
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304 | /* First time, clear store and also save my pid. */
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305 | if ((fp= fopen(PATH_DHCPPID, "w")) != nil) {
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306 | if (fprintf(fp, "%d\n", getpid()) == EOF || fclose(fp) == EOF) {
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307 | fatal(PATH_DHCPPID);
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308 | }
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309 | }
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310 | inited= 1;
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311 | mode= O_WRONLY | O_CREAT | O_TRUNC;
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312 | } else {
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313 | mode= O_WRONLY;
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314 | }
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315 |
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316 | dp->xid= htonl(now); /* To tell how old this data is. */
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317 |
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318 | if ((fd= open(cachefile, mode, 0666)) < 0
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319 | || lseek(fd, (off_t) n * sizeof(*dp), SEEK_SET) == -1
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320 | || write(fd, dp, sizeof(*dp)) < 0
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321 | || close(fd) < 0
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322 | ) {
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323 | if (errno != ENOENT) fatal(cachefile);
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324 | }
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325 | }
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326 |
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327 | static void printdata(void)
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328 | {
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329 | /* Show the contents of the cache and the dynamic pool. */
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330 | int fd;
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331 | dhcp_t d;
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332 | ssize_t r;
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333 | int i;
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334 | pool_t entry;
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335 | unsigned long expire;
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336 | char delta[3*sizeof(u32_t)];
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337 |
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338 | initdhcpconf();
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339 |
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340 | if ((fd= open(cachefile, O_RDONLY)) < 0) fatal(cachefile);
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341 | i= 0;
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342 | while ((r= read(fd, &d, sizeof(d))) == sizeof(d)) {
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343 | if (d.yiaddr != 0) {
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344 | printf("DHCP data for network %d:\n", i);
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345 | printdhcp(&d);
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346 | }
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347 | i++;
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348 | }
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349 | if (r < 0) fatal(cachefile);
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350 | close(fd);
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351 |
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352 | if ((fd= openpool(O_RDONLY)) >= 0) {
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353 | printf("Dynamic address pool since %ld:\n", (long) now);
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354 | while (readpool(fd, &entry)) {
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355 | if (entry.ip == 0) continue;
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356 | expire= ntohl(entry.expire);
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357 | if (expire == 0) {
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358 | strcpy(delta, "unused");
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359 | } else
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360 | if (expire == 0xFFFFFFFFUL) {
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361 | strcpy(delta, "infinite");
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362 | } else
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363 | if (expire < now) {
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364 | sprintf(delta, "-%lu", now - expire);
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365 | } else {
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366 | sprintf(delta, "+%lu", expire - now);
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367 | }
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368 | printf("\t%-15s %8s ", inet_ntoa(entry.ip), delta);
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369 | for (i= 0; i < entry.len; i++) {
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370 | printf("%02X", entry.clid[i]);
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371 | }
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372 | fputc('\n', stdout);
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373 | }
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374 | close(fd);
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375 | }
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376 | }
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377 |
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378 | static udpport_t portbyname(const char *name)
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379 | {
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380 | struct servent *se;
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381 |
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382 | if ((se= getservbyname(name, "udp")) == nil) {
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383 | fprintf(stderr, "%s: Unknown port \"%s\"\n", program, name);
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384 | exit(1);
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385 | }
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386 | return se->s_port;
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387 | }
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388 |
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389 | static int send(network_t *np, void *data, size_t len)
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390 | {
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391 | /* Send out a packet using a filedescriptor that is probably in async mode,
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392 | * so first dup() a sync version, then write. Return true on success.
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393 | */
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394 | int fd;
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395 | ssize_t r;
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396 |
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397 | if ((fd= dup(np->fdp->fd)) < 0) fatal("Can't dup()");
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398 | if ((r= write(fd, data, len)) < 0) {
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399 | report(np->fdp->device);
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400 | sleep(10);
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401 | }
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402 | close(fd);
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403 | return r >= 0;
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404 | }
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405 |
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406 | static size_t servdhcp(network_t *np, buf_t *bp, size_t dlen)
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407 | {
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408 | buf_t *abp= nil;
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409 | ipaddr_t cip, ifip;
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410 | u8_t defclid[1+sizeof(bp->dhcp->chaddr)];
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411 | u8_t *pdata, *client, *class, *server, *reqip, *lease;
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412 | u32_t expire;
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413 | size_t len, cilen, calen;
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414 | int type, dyn;
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415 | u8_t atype;
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416 | static char NAKMESS[] = "IP address requested isn't yours";
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417 |
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418 | if (test > 0) return 0;
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419 |
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420 | /* The IP address of the interface close to the client. */
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421 | ifip= bp->dhcp->giaddr != 0 ? bp->dhcp->giaddr : np->ip;
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422 |
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423 | /* All kinds of DHCP tags. */
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424 | if (gettag(bp->dhcp, DHCP_TAG_TYPE, &pdata, nil)) {
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425 | type= *pdata;
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426 | } else {
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427 | type= -1; /* BOOTP? */
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428 | }
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429 |
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430 | if (!gettag(bp->dhcp, DHCP_TAG_CLIENTID, &client, &cilen)) {
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431 | defclid[0]= bp->dhcp->htype;
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432 | memcpy(defclid+1, bp->dhcp->chaddr, bp->dhcp->hlen);
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433 | client= defclid;
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434 | cilen= 1+bp->dhcp->hlen;
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435 | }
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436 |
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437 | if (!gettag(bp->dhcp, DHCP_TAG_CLASSID, &class, &calen)) {
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438 | calen= 0;
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439 | }
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440 |
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441 | if (!gettag(bp->dhcp, DHCP_TAG_SERVERID, &server, nil)) {
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442 | server= B(&np->ip);
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443 | }
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444 |
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445 | if (!gettag(bp->dhcp, DHCP_TAG_REQIP, &reqip, nil)) {
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446 | reqip= nil;
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447 | }
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448 |
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449 | /* I'm a server? Then see if I know this client. */
|
---|
450 | if ((np->flags & NF_SERVING)
|
---|
451 | && bp->dhcp->op == DHCP_BOOTREQUEST
|
---|
452 | && between(1, bp->dhcp->hlen, sizeof(bp->dhcp->chaddr))
|
---|
453 | && (server == nil || memcmp(server, &np->ip, sizeof(np->ip)) == 0)
|
---|
454 | ) {
|
---|
455 | get_buf(&abp);
|
---|
456 |
|
---|
457 | /* Is the client in my tables? */
|
---|
458 | (void) makedhcp(abp->dhcp, class, calen, client, cilen, 0, ifip, nil);
|
---|
459 | cip= abp->dhcp->yiaddr;
|
---|
460 |
|
---|
461 | dyn= 0;
|
---|
462 | /* If not, do we have a dynamic address? */
|
---|
463 | if (cip == 0 && (cip= findpool(client, cilen, ifip)) != 0) dyn= 1;
|
---|
464 |
|
---|
465 | if (type == DHCP_INFORM) {
|
---|
466 | /* The client already has an address, it just wants information.
|
---|
467 | * We only answer if we could answer a normal request (cip != 0),
|
---|
468 | * unless configured to answer anyone.
|
---|
469 | */
|
---|
470 | if (cip != 0 || (np->flags & NF_INFORM)) cip= bp->dhcp->ciaddr;
|
---|
471 | }
|
---|
472 |
|
---|
473 | if (cip == 0 || !makedhcp(abp->dhcp, class, calen,
|
---|
474 | client, cilen, cip, ifip, nil)) {
|
---|
475 | put_buf(&abp);
|
---|
476 | }
|
---|
477 |
|
---|
478 | if (abp != nil) {
|
---|
479 | if (gettag(abp->dhcp, DHCP_TAG_LEASE, &lease, nil)) {
|
---|
480 | memcpy(&expire, lease, sizeof(expire));
|
---|
481 | expire= now + ntohl(expire);
|
---|
482 | if (expire < now) expire= 0xFFFFFFFFUL;
|
---|
483 | } else {
|
---|
484 | if (dyn) {
|
---|
485 | /* A dynamic address must have a lease. */
|
---|
486 | fprintf(stderr, "%s: No lease set for address %s\n",
|
---|
487 | program, inet_ntoa(cip));
|
---|
488 | exit(1);
|
---|
489 | }
|
---|
490 | lease= nil;
|
---|
491 | expire= 0xFFFFFFFFUL;
|
---|
492 | }
|
---|
493 |
|
---|
494 | /* What does our client want, and what do we say? */
|
---|
495 | switch (type) {
|
---|
496 | case DHCP_DISCOVER:
|
---|
497 | atype= DHCP_OFFER;
|
---|
498 |
|
---|
499 | /* Assign this address for a short moment. */
|
---|
500 | if (dyn && !commitpool(cip, client, cilen, now + DELTA_FAST)) {
|
---|
501 | put_buf(&abp);
|
---|
502 | }
|
---|
503 | break;
|
---|
504 |
|
---|
505 | case -1:/* BOOTP */
|
---|
506 | case DHCP_REQUEST:
|
---|
507 | case DHCP_INFORM:
|
---|
508 | atype= DHCP_ACK;
|
---|
509 | /* The address wanted must be the address we offer. */
|
---|
510 | if ((reqip != nil && memcmp(reqip, &cip, sizeof(cip)) != 0)
|
---|
511 | || (bp->dhcp->ciaddr != 0 && bp->dhcp->ciaddr != cip)
|
---|
512 | ) {
|
---|
513 | atype= DHCP_NAK;
|
---|
514 | } else
|
---|
515 | if (dyn && type == DHCP_REQUEST) {
|
---|
516 | /* Assign this address for the duration of the lease. */
|
---|
517 | if (!commitpool(cip, client, cilen, expire)) put_buf(&abp);
|
---|
518 | }
|
---|
519 | break;
|
---|
520 |
|
---|
521 | case DHCP_DECLINE:
|
---|
522 | /* Our client doesn't want the offered address! */
|
---|
523 | if (dyn
|
---|
524 | && reqip != nil
|
---|
525 | && memcmp(reqip, &cip, sizeof(cip)) == 0
|
---|
526 | ) {
|
---|
527 | int i;
|
---|
528 |
|
---|
529 | fprintf(stderr, "%s: ", program);
|
---|
530 | for (i= 0; i < cilen; i++) {
|
---|
531 | fprintf(stderr, "%02X", client[i]);
|
---|
532 | }
|
---|
533 | fprintf(stderr, " declines %s", inet_ntoa(cip));
|
---|
534 | if (gettag(bp->dhcp, DHCP_TAG_MESSAGE, &pdata, &len)) {
|
---|
535 | fprintf(stderr, " saying: \"%.*s\"", (int)len, pdata);
|
---|
536 | }
|
---|
537 | fputc('\n', stderr);
|
---|
538 |
|
---|
539 | /* Disable address for the duration of the lease. */
|
---|
540 | (void) commitpool(cip, nil, 0, expire);
|
---|
541 | }
|
---|
542 | put_buf(&abp);
|
---|
543 | break;
|
---|
544 |
|
---|
545 | case DHCP_RELEASE:
|
---|
546 | /* Our client is nice enough to return its address. */
|
---|
547 | if (dyn) (void) commitpool(cip, client, cilen, now);
|
---|
548 | put_buf(&abp);
|
---|
549 | break;
|
---|
550 |
|
---|
551 | default: /* Anything else is ignored. */
|
---|
552 | put_buf(&abp);
|
---|
553 | }
|
---|
554 | }
|
---|
555 |
|
---|
556 | if (abp != nil) {
|
---|
557 | /* Finish the return packet. */
|
---|
558 | abp->dhcp->htype= bp->dhcp->htype;
|
---|
559 | abp->dhcp->hlen= bp->dhcp->hlen;
|
---|
560 | abp->dhcp->hops= 0;
|
---|
561 | abp->dhcp->xid= bp->dhcp->xid;
|
---|
562 | abp->dhcp->secs= 0;
|
---|
563 | abp->dhcp->flags= bp->dhcp->flags;
|
---|
564 | abp->dhcp->ciaddr= 0;
|
---|
565 | abp->dhcp->yiaddr= atype == DHCP_NAK ? 0 : cip;
|
---|
566 | if (atype == DHCP_NAK) abp->dhcp->siaddr= 0;
|
---|
567 | abp->dhcp->giaddr= bp->dhcp->giaddr;
|
---|
568 | memcpy(abp->dhcp->chaddr,bp->dhcp->chaddr,sizeof(bp->dhcp->chaddr));
|
---|
569 |
|
---|
570 | settag(abp->dhcp, DHCP_TAG_SERVERID, &np->ip, sizeof(np->ip));
|
---|
571 |
|
---|
572 | if (lease == nil) {
|
---|
573 | /* No lease specified? Then give an infinite lease. */
|
---|
574 | settag(abp->dhcp, DHCP_TAG_LEASE, &expire, sizeof(expire));
|
---|
575 | }
|
---|
576 |
|
---|
577 | if (type == DHCP_INFORM) {
|
---|
578 | /* Oops, this one has a fixed address, so no lease business. */
|
---|
579 | abp->dhcp->yiaddr= 0;
|
---|
580 | settag(abp->dhcp, DHCP_TAG_LEASE, nil, 0);
|
---|
581 | settag(abp->dhcp, DHCP_TAG_RENEWAL, nil, 0);
|
---|
582 | settag(abp->dhcp, DHCP_TAG_REBINDING, nil, 0);
|
---|
583 | }
|
---|
584 |
|
---|
585 | if (atype == DHCP_NAK) {
|
---|
586 | /* A NAK doesn't need much. */
|
---|
587 | memset(abp->dhcp->sname, 0, sizeof(abp->dhcp->sname));
|
---|
588 | memset(abp->dhcp->file, 0, sizeof(abp->dhcp->file));
|
---|
589 | memset(abp->dhcp->options, 255, sizeof(abp->dhcp->options));
|
---|
590 | settag(abp->dhcp, DHCP_TAG_MESSAGE, NAKMESS, sizeof(NAKMESS));
|
---|
591 | }
|
---|
592 |
|
---|
593 | settag(abp->dhcp, DHCP_TAG_TYPE, &atype, sizeof(atype));
|
---|
594 |
|
---|
595 | /* Figure out where to send this to. */
|
---|
596 | abp->udpio->uih_src_addr= np->ip;
|
---|
597 | abp->udpio->uih_src_port= port_server;
|
---|
598 | if (bp->dhcp->giaddr != 0) {
|
---|
599 | abp->udpio->uih_dst_addr= bp->dhcp->giaddr;
|
---|
600 | abp->udpio->uih_dst_port= port_server;
|
---|
601 | } else
|
---|
602 | if (bp->dhcp->flags & DHCP_FLAGS_BCAST) {
|
---|
603 | abp->udpio->uih_dst_addr= BCAST_IP;
|
---|
604 | abp->udpio->uih_dst_port= port_client;
|
---|
605 | } else
|
---|
606 | if (bp->udpio->uih_src_addr != 0
|
---|
607 | && bp->udpio->uih_dst_addr == np->ip
|
---|
608 | ) {
|
---|
609 | abp->udpio->uih_dst_addr= bp->udpio->uih_src_addr;
|
---|
610 | abp->udpio->uih_dst_port= port_client;
|
---|
611 | } else {
|
---|
612 | abp->udpio->uih_dst_addr= BCAST_IP;
|
---|
613 | abp->udpio->uih_dst_port= port_client;
|
---|
614 | }
|
---|
615 | abp->udpio->uih_ip_opt_len= 0;
|
---|
616 | abp->udpio->uih_data_len= sizeof(dhcp_t);
|
---|
617 |
|
---|
618 | /* Copy the packet to the input buffer, and return the new size. */
|
---|
619 | memcpy(bp->buf, abp->buf, sizeof(bp->buf));
|
---|
620 | put_buf(&abp);
|
---|
621 | return sizeof(udp_io_hdr_t) + sizeof(dhcp_t);
|
---|
622 | }
|
---|
623 | }
|
---|
624 |
|
---|
625 | /* I'm a relay? If it is a not already a relayed request then relay. */
|
---|
626 | if ((np->flags & NF_RELAYING)
|
---|
627 | && bp->dhcp->op == DHCP_BOOTREQUEST
|
---|
628 | && bp->dhcp->giaddr == 0
|
---|
629 | ) {
|
---|
630 | bp->dhcp->giaddr= np->ip;
|
---|
631 | bp->udpio->uih_src_addr= np->ip;
|
---|
632 | bp->udpio->uih_src_port= port_server;
|
---|
633 | bp->udpio->uih_dst_addr= np->server;
|
---|
634 | bp->udpio->uih_dst_port= port_server;
|
---|
635 | return dlen;
|
---|
636 | }
|
---|
637 |
|
---|
638 | /* I'm a relay? If the server sends a reply to me then relay back. */
|
---|
639 | if ((np->flags & NF_RELAYING)
|
---|
640 | && bp->dhcp->op == DHCP_BOOTREPLY
|
---|
641 | && bp->dhcp->giaddr == np->ip
|
---|
642 | ) {
|
---|
643 | bp->dhcp->giaddr= 0;
|
---|
644 | bp->udpio->uih_src_addr= np->ip;
|
---|
645 | bp->udpio->uih_src_port= port_server;
|
---|
646 | bp->udpio->uih_dst_addr= BCAST_IP;
|
---|
647 | bp->udpio->uih_dst_port= port_client;
|
---|
648 | return dlen;
|
---|
649 | }
|
---|
650 |
|
---|
651 | /* Don't know what to do otherwise, so doing nothing seems wise. */
|
---|
652 | return 0;
|
---|
653 | }
|
---|
654 |
|
---|
655 | static void onsig(int sig)
|
---|
656 | {
|
---|
657 | switch (sig) {
|
---|
658 | case SIGUSR1: debug++; break;
|
---|
659 | case SIGUSR2: debug= 0; break;
|
---|
660 | }
|
---|
661 | }
|
---|
662 |
|
---|
663 | static void usage(void)
|
---|
664 | {
|
---|
665 | fprintf(stderr,
|
---|
666 | "Usage: %s [-qar] [-t[L]] [-d[L]] [-f config] [-c cache] [-p pool] [host ...]\n",
|
---|
667 | program);
|
---|
668 | exit(1);
|
---|
669 | }
|
---|
670 |
|
---|
671 | int main(int argc, char **argv)
|
---|
672 | {
|
---|
673 | int i;
|
---|
674 | network_t *np;
|
---|
675 | struct sigaction sa;
|
---|
676 | ssize_t r= -1;
|
---|
677 | buf_t *bp= nil;
|
---|
678 | static struct timeval eventtv;
|
---|
679 |
|
---|
680 | program= argv[0];
|
---|
681 | start= now= time(nil);
|
---|
682 |
|
---|
683 | debug= 0;
|
---|
684 | i= 1;
|
---|
685 | while (i < argc && argv[i][0] == '-') {
|
---|
686 | char *opt= argv[i++]+1;
|
---|
687 |
|
---|
688 | if (opt[0] == '-' && opt[1] == 0) break; /* -- */
|
---|
689 |
|
---|
690 | while (*opt != 0) switch (*opt++) {
|
---|
691 | case 'f':
|
---|
692 | if (*opt == 0) {
|
---|
693 | if (i == argc) usage();
|
---|
694 | opt= argv[i++];
|
---|
695 | }
|
---|
696 | configfile= opt;
|
---|
697 | opt= "";
|
---|
698 | break;
|
---|
699 | case 'c':
|
---|
700 | if (*opt == 0) {
|
---|
701 | if (i == argc) usage();
|
---|
702 | opt= argv[i++];
|
---|
703 | }
|
---|
704 | cachefile= opt;
|
---|
705 | opt= "";
|
---|
706 | break;
|
---|
707 | case 'p':
|
---|
708 | if (*opt == 0) {
|
---|
709 | if (i == argc) usage();
|
---|
710 | opt= argv[i++];
|
---|
711 | }
|
---|
712 | poolfile= opt;
|
---|
713 | opt= "";
|
---|
714 | break;
|
---|
715 | case 't':
|
---|
716 | test= 1;
|
---|
717 | if (between('0', *opt, '9')) test= strtoul(opt, &opt, 10);
|
---|
718 | break;
|
---|
719 | case 'd':
|
---|
720 | debug= 1;
|
---|
721 | if (between('0', *opt, '9')) debug= strtoul(opt, &opt, 10);
|
---|
722 | break;
|
---|
723 | case 'q':
|
---|
724 | qflag= 1;
|
---|
725 | break;
|
---|
726 | case 'a':
|
---|
727 | aflag= 1;
|
---|
728 | break;
|
---|
729 | case 'r':
|
---|
730 | rflag= 1;
|
---|
731 | break;
|
---|
732 | default:
|
---|
733 | usage();
|
---|
734 | }
|
---|
735 | }
|
---|
736 | if (aflag + rflag + qflag > 1) usage();
|
---|
737 |
|
---|
738 | if (aflag || rflag) {
|
---|
739 | /* Add or remove addresses from the dynamic pool. */
|
---|
740 | while (i < argc) updatepool(aflag, argv[i++]);
|
---|
741 | exit(0);
|
---|
742 | }
|
---|
743 |
|
---|
744 | if (i != argc) usage();
|
---|
745 |
|
---|
746 | if (qflag) {
|
---|
747 | /* Only show the contents of the cache and dynamic pool to the user. */
|
---|
748 | printdata();
|
---|
749 | exit(0);
|
---|
750 | }
|
---|
751 |
|
---|
752 | /* BOOTP ports. */
|
---|
753 | port_server= portbyname("bootps");
|
---|
754 | port_client= portbyname("bootpc");
|
---|
755 |
|
---|
756 | sa.sa_handler= onsig;
|
---|
757 | sigemptyset(&sa.sa_mask);
|
---|
758 | sa.sa_flags= 0;
|
---|
759 | sigaction(SIGUSR1, &sa, nil);
|
---|
760 | sigaction(SIGUSR2, &sa, nil);
|
---|
761 |
|
---|
762 | /* Initial configuration. */
|
---|
763 | for (i= 0; i < N_NETS; i++) {
|
---|
764 | int fd;
|
---|
765 | ipaddr_t ip, mask;
|
---|
766 |
|
---|
767 | /* Is there something there? */
|
---|
768 | if ((fd= open(ipdev(i), O_RDWR|O_NONBLOCK)) < 0) {
|
---|
769 | if (errno != ENOENT && errno != ENODEV && errno != ENXIO) {
|
---|
770 | fatal(ipdev(i));
|
---|
771 | }
|
---|
772 | continue;
|
---|
773 | }
|
---|
774 | close(fd);
|
---|
775 |
|
---|
776 | network[n_nets++]= np= newnetwork();
|
---|
777 | np->n= i;
|
---|
778 |
|
---|
779 | /* Ethernet? */
|
---|
780 | if (opendev(np, FT_ETHERNET, 1)) {
|
---|
781 | np->type= B(&np->eth)[0] != 'Z' ? NT_ETHERNET : NT_SINK;
|
---|
782 | if (debug >= 1) {
|
---|
783 | printf("%s: Ethernet address is %s%s\n",
|
---|
784 | np->fdp->device, ether_ntoa(&np->eth),
|
---|
785 | np->type == NT_SINK ? " (sink)" : "");
|
---|
786 | }
|
---|
787 | closedev(np, FT_ETHERNET);
|
---|
788 | }
|
---|
789 |
|
---|
790 | /* Only true Ethernets worry about DHCP. */
|
---|
791 | if (np->type != NT_ETHERNET) np->renew= np->rebind= np->lease= NEVER;
|
---|
792 | }
|
---|
793 |
|
---|
794 | /* Try to find my interfaces in the DHCP table. */
|
---|
795 | for (i= 0; i < n_nets; i++) {
|
---|
796 | ipaddr_t cip;
|
---|
797 | u8_t clid[1+DHCP_HLEN_ETH];
|
---|
798 | size_t cilen;
|
---|
799 |
|
---|
800 | np= network[i];
|
---|
801 | if (np->flags & NF_BOUND) continue;
|
---|
802 |
|
---|
803 | if (np->type == NT_IP) {
|
---|
804 | cilen= 0;
|
---|
805 | } else {
|
---|
806 | ether2clid(clid, &np->eth);
|
---|
807 | cilen= 1+DHCP_HLEN_ETH;
|
---|
808 | }
|
---|
809 |
|
---|
810 | /* Try to find an Ethernet address, or the IP address of an already
|
---|
811 | * configured network. If we have data we get an IP address back.
|
---|
812 | */
|
---|
813 | get_buf(&bp);
|
---|
814 | (void) makedhcp(bp->dhcp, (u8_t *) "Minix", 5,
|
---|
815 | clid, cilen, np->ip, 0, np);
|
---|
816 | cip= bp->dhcp->yiaddr;
|
---|
817 |
|
---|
818 | /* Gather information on the interface. */
|
---|
819 | if (cip != 0
|
---|
820 | && makedhcp(bp->dhcp, (u8_t *) "Minix", 5,
|
---|
821 | clid, cilen, cip, cip, np)
|
---|
822 | && test < 2
|
---|
823 | ) {
|
---|
824 | u8_t *pdata;
|
---|
825 | u16_t mtu;
|
---|
826 |
|
---|
827 | cachedhcp(np->n, bp->dhcp);
|
---|
828 | np->ip= cip;
|
---|
829 | (void) gettag(bp->dhcp, DHCP_TAG_NETMASK, &pdata, nil);
|
---|
830 | memcpy(&np->mask, pdata, sizeof(np->mask));
|
---|
831 | if (gettag(bp->dhcp, DHCP_TAG_GATEWAY, &pdata, nil)) {
|
---|
832 | memcpy(&np->gateway, pdata, sizeof(np->gateway));
|
---|
833 | } else {
|
---|
834 | np->gateway= 0;
|
---|
835 | }
|
---|
836 | if (gettag(bp->dhcp, DHCP_TAG_IPMTU, &pdata, nil)) {
|
---|
837 | memcpy(&mtu, pdata, sizeof(mtu));
|
---|
838 | mtu= ntohs(mtu);
|
---|
839 | } else {
|
---|
840 | mtu= 0;
|
---|
841 | }
|
---|
842 | set_ipconf(ipdev(np->n), np->ip, np->mask, mtu);
|
---|
843 | if (debug >= 1) {
|
---|
844 | printf("%s: IP address is %s\n",
|
---|
845 | ipdev(np->n), cidr_ntoa(np->ip, np->mask));
|
---|
846 | }
|
---|
847 | np->flags |= NF_BOUND;
|
---|
848 | np->renew= np->rebind= np->lease= NEVER;
|
---|
849 | np->sol_ct= N_SOLICITS;
|
---|
850 | np->solicit= 0;
|
---|
851 |
|
---|
852 | /* Other (previous) interfaces may have been defined. */
|
---|
853 | i= 0;
|
---|
854 | }
|
---|
855 | put_buf(&bp);
|
---|
856 | }
|
---|
857 |
|
---|
858 | for (;;) {
|
---|
859 | now= time(nil);
|
---|
860 | event= NEVER;
|
---|
861 |
|
---|
862 | /* Is it time to request/renew a lease? */
|
---|
863 | for (i= 0; i < n_nets; i++) {
|
---|
864 | np= network[i];
|
---|
865 |
|
---|
866 | if (np->renew <= now) {
|
---|
867 | u8_t type;
|
---|
868 | static u8_t taglist[] = {
|
---|
869 | DHCP_TAG_NETMASK, DHCP_TAG_GATEWAY, DHCP_TAG_DNS,
|
---|
870 | DHCP_TAG_HOSTNAME
|
---|
871 | };
|
---|
872 | u8_t ethclid[1+DHCP_HLEN_ETH];
|
---|
873 |
|
---|
874 | /* We may have lost our binding or even our lease. */
|
---|
875 | if (np->rebind <= now) np->server= BCAST_IP;
|
---|
876 |
|
---|
877 | if (np->lease <= now) {
|
---|
878 | if (np->flags & NF_BOUND) closedev(np, FT_ALL);
|
---|
879 |
|
---|
880 | if ((np->flags & (NF_BOUND | NF_POSSESSIVE)) == NF_BOUND) {
|
---|
881 | set_ipconf(ipdev(np->n), np->ip= 0, np->mask= 0, 0);
|
---|
882 | if (debug >= 1) {
|
---|
883 | printf("%s: Interface disabled (lease expired)\n",
|
---|
884 | ipdev(np->n));
|
---|
885 | }
|
---|
886 | }
|
---|
887 | np->flags &= ~NF_BOUND;
|
---|
888 | }
|
---|
889 |
|
---|
890 | /* See if we can open the network we need to send on. */
|
---|
891 | if (!(np->flags & NF_BOUND)) {
|
---|
892 | if (!opendev(np, FT_ETHERNET, 1)) continue;
|
---|
893 | } else {
|
---|
894 | if (!opendev(np, FT_BOOTPC, 1)) continue;
|
---|
895 | }
|
---|
896 |
|
---|
897 | if (!(np->flags & NF_NEGOTIATING)) {
|
---|
898 | /* We need to start querying a DHCP server. */
|
---|
899 | np->start= now;
|
---|
900 | np->delta= DELTA_FIRST;
|
---|
901 | np->flags |= NF_NEGOTIATING;
|
---|
902 | }
|
---|
903 |
|
---|
904 | /* Fill in a DHCP query packet. */
|
---|
905 | get_buf(&bp);
|
---|
906 | dhcp_init(bp->dhcp);
|
---|
907 | bp->dhcp->op= DHCP_BOOTREQUEST;
|
---|
908 | bp->dhcp->htype= DHCP_HTYPE_ETH;
|
---|
909 | bp->dhcp->hlen= DHCP_HLEN_ETH;
|
---|
910 | bp->dhcp->xid= XID(np);
|
---|
911 | bp->dhcp->secs= htons(now - np->start > 0xFFFF
|
---|
912 | ? 0xFFFF : now - np->start);
|
---|
913 | memcpy(bp->dhcp->chaddr, &np->eth, sizeof(np->eth));
|
---|
914 |
|
---|
915 | if (np->lease <= now) {
|
---|
916 | /* First time, or my old server is unresponsive. */
|
---|
917 | type= DHCP_DISCOVER;
|
---|
918 | } else {
|
---|
919 | /* Request an offered address or renew an address. */
|
---|
920 | type= DHCP_REQUEST;
|
---|
921 | if (np->flags & NF_BOUND) {
|
---|
922 | /* A renewal, I claim my current address. */
|
---|
923 | bp->dhcp->ciaddr= np->ip;
|
---|
924 | } else {
|
---|
925 | /* Nicely ask for the address just offered. */
|
---|
926 | settag(bp->dhcp, DHCP_TAG_REQIP, &np->ip,
|
---|
927 | sizeof(np->ip));
|
---|
928 | settag(bp->dhcp, DHCP_TAG_SERVERID, &np->server,
|
---|
929 | sizeof(np->server));
|
---|
930 | }
|
---|
931 | }
|
---|
932 | settag(bp->dhcp, DHCP_TAG_TYPE, &type, 1);
|
---|
933 |
|
---|
934 | /* My client ID. Simply use the default. */
|
---|
935 | ether2clid(ethclid, &np->eth);
|
---|
936 | settag(bp->dhcp, DHCP_TAG_CLIENTID, ethclid, sizeof(ethclid));
|
---|
937 |
|
---|
938 | /* The Class ID may serve to recognize Minix hosts. */
|
---|
939 | settag(bp->dhcp, DHCP_TAG_CLASSID, "Minix", 5);
|
---|
940 |
|
---|
941 | /* The few tags that Minix can make good use of. */
|
---|
942 | settag(bp->dhcp, DHCP_TAG_REQPAR, taglist, sizeof(taglist));
|
---|
943 |
|
---|
944 | /* Some weird sites use a hostname, not a client ID. */
|
---|
945 | if (np->hostname != nil) {
|
---|
946 | settag(bp->dhcp, DHCP_TAG_HOSTNAME,
|
---|
947 | np->hostname, strlen(np->hostname));
|
---|
948 | }
|
---|
949 |
|
---|
950 | bp->udpio->uih_src_addr= np->ip;
|
---|
951 | bp->udpio->uih_dst_addr= np->server;
|
---|
952 | bp->udpio->uih_src_port= port_client;
|
---|
953 | bp->udpio->uih_dst_port= port_server;
|
---|
954 | bp->udpio->uih_ip_opt_len= 0;
|
---|
955 | bp->udpio->uih_data_len= sizeof(dhcp_t);
|
---|
956 |
|
---|
957 | if (!(np->flags & NF_BOUND)) {
|
---|
958 | /* Rebind over Ethernet. */
|
---|
959 | udp2ether(bp, np);
|
---|
960 | if (send(np, bp->eth, sizeof(eth_hdr_t) + sizeof(ip_hdr_t)
|
---|
961 | + sizeof(udp_hdr_t) + sizeof(dhcp_t))) {
|
---|
962 | if (debug >= 1) {
|
---|
963 | printf("%s: Broadcast DHCP %s\n",
|
---|
964 | np->fdp->device, dhcptypename(type));
|
---|
965 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
966 | }
|
---|
967 | }
|
---|
968 | } else {
|
---|
969 | /* Renew over UDP. */
|
---|
970 | if (send(np, bp->udpio, sizeof(udp_io_hdr_t)
|
---|
971 | + sizeof(dhcp_t))) {
|
---|
972 | if (debug >= 1) {
|
---|
973 | printf("%s: Sent DHCP %s to %s\n",
|
---|
974 | np->fdp->device,
|
---|
975 | dhcptypename(type),
|
---|
976 | inet_ntoa(np->server));
|
---|
977 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
978 | }
|
---|
979 | }
|
---|
980 | }
|
---|
981 | put_buf(&bp);
|
---|
982 |
|
---|
983 | /* When to continue querying a DHCP server? */
|
---|
984 | if (np->flags & NF_BOUND) {
|
---|
985 | /* Still bound, keep halving time till next event. */
|
---|
986 | time_t e, d;
|
---|
987 |
|
---|
988 | e= now < np->rebind ? np->rebind : np->lease;
|
---|
989 | d= (e - now) / 2;
|
---|
990 | if (d < DELTA_SLOW) d= DELTA_SLOW;
|
---|
991 | np->renew= now + d;
|
---|
992 | if (np->renew > e) np->renew= e;
|
---|
993 | } else {
|
---|
994 | /* Not bound, be desparate. */
|
---|
995 | np->renew= now + np->delta;
|
---|
996 | if ((np->delta *= 2) > DELTA_FAST) np->delta= DELTA_FAST;
|
---|
997 | }
|
---|
998 | }
|
---|
999 | if (np->renew < event) event= np->renew;
|
---|
1000 | }
|
---|
1001 |
|
---|
1002 | /* Read DHCP responses. */
|
---|
1003 | for (i= 0; i < n_nets; i++) {
|
---|
1004 | np= network[i];
|
---|
1005 | if (!(np->flags & NF_NEGOTIATING)) continue;
|
---|
1006 |
|
---|
1007 | if (!(np->flags & NF_BOUND)) {
|
---|
1008 | if (!opendev(np, FT_ETHERNET, 0)) continue;
|
---|
1009 | get_buf(&np->fdp->bp);
|
---|
1010 | r= asyn_read(&asyn, np->fdp->fd, np->fdp->bp->eth,
|
---|
1011 | BUF_ETH_SIZE);
|
---|
1012 | } else {
|
---|
1013 | if (!opendev(np, FT_BOOTPC, 0)) continue;
|
---|
1014 | get_buf(&np->fdp->bp);
|
---|
1015 | r= asyn_read(&asyn, np->fdp->fd, np->fdp->bp->udpio,
|
---|
1016 | BUF_UDP_SIZE);
|
---|
1017 | }
|
---|
1018 | if (r != -1) break;
|
---|
1019 | if (errno != ASYN_INPROGRESS && errno != EPACKSIZE) {
|
---|
1020 | report(np->fdp->device);
|
---|
1021 | sleep(10);
|
---|
1022 | }
|
---|
1023 | }
|
---|
1024 |
|
---|
1025 | /* Is there a response? */
|
---|
1026 | if (i < n_nets) {
|
---|
1027 | give_buf(&bp, &np->fdp->bp);
|
---|
1028 | if (((!(np->flags & NF_BOUND)
|
---|
1029 | && r >= (sizeof(eth_hdr_t) + sizeof(ip_hdr_t)
|
---|
1030 | + sizeof(udp_hdr_t) + offsetof(dhcp_t, options))
|
---|
1031 | && ether2udp(bp)
|
---|
1032 | && bp->udpio->uih_dst_port == port_client)
|
---|
1033 | ||
|
---|
1034 | ((np->flags & NF_BOUND)
|
---|
1035 | && r >= sizeof(udp_io_hdr_t) + offsetof(dhcp_t, options)))
|
---|
1036 | && bp->dhcp->op == DHCP_BOOTREPLY
|
---|
1037 | && bp->dhcp->htype == DHCP_HTYPE_ETH
|
---|
1038 | && bp->dhcp->hlen == DHCP_HLEN_ETH
|
---|
1039 | && bp->dhcp->xid == XID(np)
|
---|
1040 | && memcmp(bp->dhcp->chaddr, &np->eth, sizeof(np->eth)) == 0
|
---|
1041 | ) {
|
---|
1042 | /* Pfew! We got a DHCP reply! */
|
---|
1043 | u8_t *pdata;
|
---|
1044 | size_t len;
|
---|
1045 | int type;
|
---|
1046 | ipaddr_t mask, gateway, relay, server;
|
---|
1047 | u16_t mtu;
|
---|
1048 | u32_t lease, renew, rebind, t;
|
---|
1049 |
|
---|
1050 | relay= bp->udpio->uih_src_addr;
|
---|
1051 | if (gettag(bp->dhcp, DHCP_TAG_SERVERID, &pdata, nil)) {
|
---|
1052 | memcpy(&server, pdata, sizeof(server));
|
---|
1053 | } else {
|
---|
1054 | server= relay;
|
---|
1055 | }
|
---|
1056 |
|
---|
1057 | if (gettag(bp->dhcp, DHCP_TAG_TYPE, &pdata, nil)) {
|
---|
1058 | type= pdata[0];
|
---|
1059 | } else {
|
---|
1060 | type= DHCP_ACK; /* BOOTP? */
|
---|
1061 | }
|
---|
1062 |
|
---|
1063 | if (debug >= 1) {
|
---|
1064 | printf("%s: Got a DHCP %s from %s",
|
---|
1065 | np->fdp->device, dhcptypename(type), inet_ntoa(server));
|
---|
1066 | printf(relay != server ? " through %s\n" : "\n",
|
---|
1067 | inet_ntoa(relay));
|
---|
1068 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
1069 | }
|
---|
1070 |
|
---|
1071 | if (gettag(bp->dhcp, DHCP_TAG_NETMASK, &pdata, nil)) {
|
---|
1072 | memcpy(&mask, pdata, sizeof(mask));
|
---|
1073 | } else {
|
---|
1074 | mask= defaultmask(bp->dhcp->ciaddr);
|
---|
1075 | }
|
---|
1076 |
|
---|
1077 | if (gettag(bp->dhcp, DHCP_TAG_IPMTU, &pdata, nil)) {
|
---|
1078 | memcpy(&mtu, pdata, sizeof(mtu));
|
---|
1079 | mtu= ntohs(mtu);
|
---|
1080 | } else {
|
---|
1081 | mtu= 0;
|
---|
1082 | }
|
---|
1083 |
|
---|
1084 | if (gettag(bp->dhcp, DHCP_TAG_GATEWAY, &pdata, nil)) {
|
---|
1085 | memcpy(&gateway, pdata, sizeof(gateway));
|
---|
1086 | } else {
|
---|
1087 | gateway= 0;
|
---|
1088 | }
|
---|
1089 |
|
---|
1090 | lease= NEVER;
|
---|
1091 | if (gettag(bp->dhcp, DHCP_TAG_LEASE, &pdata, nil)) {
|
---|
1092 | memcpy(&lease, pdata, sizeof(lease));
|
---|
1093 | lease= ntohl(lease);
|
---|
1094 | }
|
---|
1095 |
|
---|
1096 | rebind= lease - lease / 8;
|
---|
1097 | if (gettag(bp->dhcp, DHCP_TAG_REBINDING, &pdata, nil)) {
|
---|
1098 | memcpy(&t, pdata, sizeof(t));
|
---|
1099 | t= ntohl(t);
|
---|
1100 | if (t < rebind) rebind= t;
|
---|
1101 | }
|
---|
1102 |
|
---|
1103 | renew= lease / 2;
|
---|
1104 | if (gettag(bp->dhcp, DHCP_TAG_RENEWAL, &pdata, nil)) {
|
---|
1105 | memcpy(&t, pdata, sizeof(t));
|
---|
1106 | t= ntohl(t);
|
---|
1107 | if (t < renew) renew= t;
|
---|
1108 | }
|
---|
1109 |
|
---|
1110 | if (type == DHCP_OFFER && np->rebind <= np->renew) {
|
---|
1111 | /* It's an offer for an address and we haven't taken one
|
---|
1112 | * yet. It's all the same to us, so take this one.
|
---|
1113 | */
|
---|
1114 | np->ip= bp->dhcp->yiaddr;
|
---|
1115 | np->mask= mask;
|
---|
1116 | np->server= server;
|
---|
1117 | np->gateway= gateway;
|
---|
1118 | np->delta= DELTA_FIRST;
|
---|
1119 | np->renew= now;
|
---|
1120 | np->rebind= np->lease= now + DELTA_FAST;
|
---|
1121 |
|
---|
1122 | /* Send out an ARP request to see if the offered address
|
---|
1123 | * is in use already.
|
---|
1124 | */
|
---|
1125 | make_arp(bp, np);
|
---|
1126 | if (send(np, bp->eth, sizeof(arp46_t))) {
|
---|
1127 | if (debug >= 2) {
|
---|
1128 | printf("Sent ARP for %s\n", inet_ntoa(np->ip));
|
---|
1129 | }
|
---|
1130 | }
|
---|
1131 | np->flags &= ~NF_CONFLICT;
|
---|
1132 | }
|
---|
1133 |
|
---|
1134 | if (type == DHCP_ACK && !(np->flags & NF_CONFLICT)) {
|
---|
1135 | /* An acknowledgment. The address is all mine. */
|
---|
1136 | cachedhcp(np->n, bp->dhcp);
|
---|
1137 | np->ip= bp->dhcp->yiaddr;
|
---|
1138 | np->mask= mask;
|
---|
1139 | np->server= server;
|
---|
1140 | set_ipconf(ipdev(np->n), np->ip, np->mask, mtu);
|
---|
1141 | if (debug >= 1) {
|
---|
1142 | printf("%s: Address set to %s\n",
|
---|
1143 | ipdev(np->n), cidr_ntoa(np->ip, np->mask));
|
---|
1144 | }
|
---|
1145 | if (lease >= NEVER - now) {
|
---|
1146 | /* The lease is infinite! */
|
---|
1147 | np->renew= np->rebind= np->lease= NEVER;
|
---|
1148 | } else {
|
---|
1149 | np->lease= now + lease;
|
---|
1150 | np->renew= now + renew;
|
---|
1151 | np->rebind= now + rebind;
|
---|
1152 | }
|
---|
1153 | if (test >= 3) {
|
---|
1154 | np->renew= now + 60;
|
---|
1155 | np->rebind= test >= 4 ? np->renew : np->renew + 60;
|
---|
1156 | np->lease= test >= 5 ? np->rebind : np->rebind + 60;
|
---|
1157 | }
|
---|
1158 | if (!(np->flags & NF_IRDP)) {
|
---|
1159 | np->sol_ct= (np->flags & NF_BOUND) ? 1 : N_SOLICITS;
|
---|
1160 | np->solicit= 0;
|
---|
1161 | }
|
---|
1162 | np->flags &= ~NF_NEGOTIATING;
|
---|
1163 | np->flags |= NF_BOUND;
|
---|
1164 | closedev(np, FT_ETHERNET);
|
---|
1165 | closedev(np, FT_BOOTPC);
|
---|
1166 | }
|
---|
1167 |
|
---|
1168 | if (type == DHCP_ACK && (np->flags & NF_CONFLICT)) {
|
---|
1169 | /* Alas there is a conflict. Decline to use the address. */
|
---|
1170 | u8_t ethclid[1+DHCP_HLEN_ETH];
|
---|
1171 | static char USED[]= "Address in use by 00:00:00:00:00:00";
|
---|
1172 |
|
---|
1173 | type= DHCP_DECLINE;
|
---|
1174 | dhcp_init(bp->dhcp);
|
---|
1175 | bp->dhcp->op= DHCP_BOOTREQUEST;
|
---|
1176 | bp->dhcp->htype= DHCP_HTYPE_ETH;
|
---|
1177 | bp->dhcp->hlen= DHCP_HLEN_ETH;
|
---|
1178 | bp->dhcp->xid= XID(np);
|
---|
1179 | bp->dhcp->secs= 0;
|
---|
1180 | memcpy(bp->dhcp->chaddr, &np->eth, sizeof(np->eth));
|
---|
1181 | settag(bp->dhcp, DHCP_TAG_REQIP, &np->ip, sizeof(np->ip));
|
---|
1182 | settag(bp->dhcp, DHCP_TAG_TYPE, &type, 1);
|
---|
1183 | ether2clid(ethclid, &np->eth);
|
---|
1184 | settag(bp->dhcp, DHCP_TAG_CLIENTID,ethclid,sizeof(ethclid));
|
---|
1185 | strcpy(USED+18, ether_ntoa(&np->conflict));
|
---|
1186 | settag(bp->dhcp, DHCP_TAG_MESSAGE, USED, strlen(USED));
|
---|
1187 |
|
---|
1188 | bp->udpio->uih_src_port= port_client;
|
---|
1189 | bp->udpio->uih_dst_port= port_server;
|
---|
1190 | bp->udpio->uih_ip_opt_len= 0;
|
---|
1191 | bp->udpio->uih_data_len= sizeof(dhcp_t);
|
---|
1192 | udp2ether(bp, np);
|
---|
1193 |
|
---|
1194 | if (send(np, bp->eth, sizeof(eth_hdr_t) + sizeof(ip_hdr_t)
|
---|
1195 | + sizeof(udp_hdr_t) + sizeof(dhcp_t))) {
|
---|
1196 | if (debug >= 1) {
|
---|
1197 | printf("%s: Broadcast DHCP %s\n",
|
---|
1198 | np->fdp->device, dhcptypename(type));
|
---|
1199 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
1200 | }
|
---|
1201 | }
|
---|
1202 |
|
---|
1203 | np->renew= np->rebind= np->lease= now + DELTA_FAST;
|
---|
1204 | np->delta= DELTA_FIRST;
|
---|
1205 | }
|
---|
1206 |
|
---|
1207 | if (type == DHCP_NAK) {
|
---|
1208 | /* Oops, a DHCP server doesn't like me, start over! */
|
---|
1209 | np->renew= np->rebind= np->lease= now + DELTA_FAST;
|
---|
1210 | np->delta= DELTA_FIRST;
|
---|
1211 |
|
---|
1212 | fprintf(stderr, "%s: Got a NAK from %s",
|
---|
1213 | program, inet_ntoa(server));
|
---|
1214 | if (relay != server) {
|
---|
1215 | fprintf(stderr, " through %s", inet_ntoa(relay));
|
---|
1216 | }
|
---|
1217 | if (gettag(bp->dhcp, DHCP_TAG_MESSAGE, &pdata, &len)) {
|
---|
1218 | fprintf(stderr, " saying: \"%.*s\"", (int)len, pdata);
|
---|
1219 | }
|
---|
1220 | fputc('\n', stderr);
|
---|
1221 | }
|
---|
1222 | } else
|
---|
1223 | if (!(np->flags & NF_BOUND)
|
---|
1224 | && np->rebind > now
|
---|
1225 | && r >= sizeof(arp46_t)
|
---|
1226 | && is_arp_me(bp, np)
|
---|
1227 | ) {
|
---|
1228 | /* Oh no, someone else is using the address offered to me! */
|
---|
1229 | np->flags |= NF_CONFLICT;
|
---|
1230 |
|
---|
1231 | fprintf(stderr, "%s: %s: %s offered by ",
|
---|
1232 | program,
|
---|
1233 | np->fdp->device,
|
---|
1234 | inet_ntoa(np->ip));
|
---|
1235 | fprintf(stderr, "%s is already in use by %s\n",
|
---|
1236 | inet_ntoa(np->server),
|
---|
1237 | ether_ntoa(&np->conflict));
|
---|
1238 | }
|
---|
1239 | put_buf(&bp);
|
---|
1240 | if (np->renew < event) event= np->renew;
|
---|
1241 | }
|
---|
1242 |
|
---|
1243 | /* Perform router solicitations. */
|
---|
1244 | for (i= 0; i < n_nets; i++) {
|
---|
1245 | np= network[i];
|
---|
1246 | if (!(np->flags & NF_BOUND)) continue;
|
---|
1247 |
|
---|
1248 | if (np->solicit <= now) {
|
---|
1249 | if (!opendev(np, FT_ICMP, 1)) continue;
|
---|
1250 | np->solicit= NEVER;
|
---|
1251 |
|
---|
1252 | get_buf(&bp);
|
---|
1253 | if (np->gateway != 0) {
|
---|
1254 | /* No IRDP response seen yet, advertise the router given
|
---|
1255 | * by DHCP to my own interface.
|
---|
1256 | */
|
---|
1257 | icmp_advert(bp, np);
|
---|
1258 | if (send(np, bp->ip, sizeof(ip_hdr_t) + 16)) {
|
---|
1259 | if (debug >= 2) {
|
---|
1260 | printf("%s: Sent advert for %s to self\n",
|
---|
1261 | np->fdp->device, inet_ntoa(np->gateway));
|
---|
1262 | }
|
---|
1263 | }
|
---|
1264 | np->solicit= now + DELTA_ADV/2;
|
---|
1265 | }
|
---|
1266 |
|
---|
1267 | if (np->sol_ct >= 0 && --np->sol_ct >= 0) {
|
---|
1268 | /* Send a router solicitation. */
|
---|
1269 | icmp_solicit(bp);
|
---|
1270 | if (send(np, bp->ip, sizeof(*bp->ip) + 8)) {
|
---|
1271 | if (debug >= 2) {
|
---|
1272 | printf("%s: Broadcast router solicitation\n",
|
---|
1273 | np->fdp->device);
|
---|
1274 | }
|
---|
1275 | }
|
---|
1276 | np->solicit= now + DELTA_SOL;
|
---|
1277 | } else {
|
---|
1278 | /* No response, or not soliciting right now. */
|
---|
1279 | closedev(np, FT_ICMP);
|
---|
1280 | }
|
---|
1281 |
|
---|
1282 | put_buf(&bp);
|
---|
1283 | }
|
---|
1284 | if (np->solicit < event) event= np->solicit;
|
---|
1285 | }
|
---|
1286 |
|
---|
1287 | /* Read router adverts. */
|
---|
1288 | for (i= 0; i < n_nets; i++) {
|
---|
1289 | np= network[i];
|
---|
1290 | if (!(np->flags & NF_BOUND)) continue;
|
---|
1291 | if (np->sol_ct < 0) continue;
|
---|
1292 |
|
---|
1293 | if (!opendev(np, FT_ICMP, 0)) continue;
|
---|
1294 | get_buf(&np->fdp->bp);
|
---|
1295 | r= asyn_read(&asyn, np->fdp->fd, np->fdp->bp->ip, BUF_IP_SIZE);
|
---|
1296 | if (r != -1) break;
|
---|
1297 | if (errno != ASYN_INPROGRESS && errno != EPACKSIZE) {
|
---|
1298 | report(np->fdp->device);
|
---|
1299 | sleep(10);
|
---|
1300 | }
|
---|
1301 | }
|
---|
1302 |
|
---|
1303 | /* Is there an advert? */
|
---|
1304 | if (i < n_nets && r >= sizeof(ip_hdr_t) + 8) {
|
---|
1305 | ipaddr_t router;
|
---|
1306 |
|
---|
1307 | give_buf(&bp, &np->fdp->bp);
|
---|
1308 | if ((router= icmp_is_advert(bp)) != 0) {
|
---|
1309 | if (debug >= 2) {
|
---|
1310 | printf("%s: Router advert received from %s\n",
|
---|
1311 | np->fdp->device, inet_ntoa(router));
|
---|
1312 | }
|
---|
1313 | np->solicit= NEVER;
|
---|
1314 | np->sol_ct= -1;
|
---|
1315 | np->flags |= NF_IRDP;
|
---|
1316 | closedev(np, FT_ICMP);
|
---|
1317 | }
|
---|
1318 | put_buf(&bp);
|
---|
1319 | }
|
---|
1320 |
|
---|
1321 | /* We start serving if all the interfaces so marked are configured. */
|
---|
1322 | for (i= 0; i < n_nets; i++) {
|
---|
1323 | np= network[i];
|
---|
1324 | if ((np->flags & NF_RELAYING) && (np->flags & NF_BOUND)) {
|
---|
1325 | if (((np->ip ^ np->server) & np->mask) == 0) {
|
---|
1326 | /* Don't relay to a server that is on this same net. */
|
---|
1327 | np->flags &= ~NF_RELAYING;
|
---|
1328 | }
|
---|
1329 | }
|
---|
1330 | if (!(np->flags & (NF_SERVING|NF_RELAYING))) continue;
|
---|
1331 | if (!(np->flags & NF_BOUND)) { serving= 0; break; }
|
---|
1332 | serving= 1;
|
---|
1333 | }
|
---|
1334 |
|
---|
1335 | /* Read DHCP requests. */
|
---|
1336 | for (i= 0; i < n_nets; i++) {
|
---|
1337 | np= network[i];
|
---|
1338 | if (!(np->flags & NF_BOUND)) continue;
|
---|
1339 | if (!(np->flags & (NF_SERVING|NF_RELAYING)) || !serving) continue;
|
---|
1340 |
|
---|
1341 | if (!opendev(np, FT_BOOTPS, 0)) continue;
|
---|
1342 | get_buf(&np->fdp->bp);
|
---|
1343 | r= asyn_read(&asyn, np->fdp->fd, np->fdp->bp->udpio, BUF_UDP_SIZE);
|
---|
1344 |
|
---|
1345 | if (r != -1) break;
|
---|
1346 | if (errno != ASYN_INPROGRESS && errno != EPACKSIZE) {
|
---|
1347 | report(np->fdp->device);
|
---|
1348 | sleep(10);
|
---|
1349 | }
|
---|
1350 | }
|
---|
1351 |
|
---|
1352 | /* Is there a request? */
|
---|
1353 | if (i < n_nets
|
---|
1354 | && r >= sizeof(udp_io_hdr_t) + offsetof(dhcp_t, options)
|
---|
1355 | ) {
|
---|
1356 | give_buf(&bp, &np->fdp->bp);
|
---|
1357 |
|
---|
1358 | if (debug >= 1) {
|
---|
1359 | printf("%s: Got DHCP packet from %s to ",
|
---|
1360 | np->fdp->device, inet_ntoa(bp->udpio->uih_src_addr));
|
---|
1361 | printf("%s\n", inet_ntoa(bp->udpio->uih_dst_addr));
|
---|
1362 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
1363 | }
|
---|
1364 |
|
---|
1365 | /* Can we do something with this DHCP packet? */
|
---|
1366 | if ((r= servdhcp(np, bp, r)) > 0) {
|
---|
1367 | /* Yes, we have something to send somewhere. */
|
---|
1368 | if (send(np, bp->udpio, r)) {
|
---|
1369 | if (debug >= 1) {
|
---|
1370 | printf("%s: Sent DHCP packet to %s\n",
|
---|
1371 | np->fdp->device,
|
---|
1372 | inet_ntoa(bp->udpio->uih_dst_addr));
|
---|
1373 | if (debug >= 2) printdhcp(bp->dhcp);
|
---|
1374 | }
|
---|
1375 | }
|
---|
1376 | }
|
---|
1377 | put_buf(&bp);
|
---|
1378 | }
|
---|
1379 |
|
---|
1380 | if (debug >= 1) {
|
---|
1381 | static char *lastbrk;
|
---|
1382 | extern char _end;
|
---|
1383 |
|
---|
1384 | if (sbrk(0) != lastbrk) {
|
---|
1385 | lastbrk= sbrk(0);
|
---|
1386 | printf("Memory use = %lu\n",
|
---|
1387 | (unsigned long) (lastbrk - &_end));
|
---|
1388 | }
|
---|
1389 | fflush(stdout);
|
---|
1390 | }
|
---|
1391 |
|
---|
1392 | /* Bail out if not a server, and there is nothing else to do ever. */
|
---|
1393 | if (!serving && event == NEVER) break;
|
---|
1394 |
|
---|
1395 | /* Wait for something to do. */
|
---|
1396 | eventtv.tv_sec= event;
|
---|
1397 | if (asyn_wait(&asyn, 0, event == NEVER ? nil : &eventtv) < 0) {
|
---|
1398 | if (errno != EINTR) {
|
---|
1399 | report("asyn_wait()");
|
---|
1400 | sleep(10);
|
---|
1401 | }
|
---|
1402 | }
|
---|
1403 | }
|
---|
1404 | if (debug >= 1) printf("Nothing more to do! Bailing out...\n");
|
---|
1405 | return 0;
|
---|
1406 | }
|
---|