experiment5.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <string.h>
   5
   6 typedef struct line LINE;
   7
   8 struct line {
   9     unsigned long int mac;
  10     unsigned long int ip;
  11     char *fqdn;
  12     LINE *next;
  13 };
  14
  15 LINE *first = NULL;
  16 LINE *last  = NULL;
  17 LINE *array   = NULL;
  18
  19 int listlen = 0;
  20
  21 int add(unsigned long int mac, unsigned long int ip, char *fqdn) {
  22     LINE *new = malloc(sizeof(LINE));
  23     new->mac = mac;
  24     new->ip  = ip;
  25     new->fqdn = strdup(fqdn);
  26     new->next = NULL;
  27
  28     if (!first)
  29         first = new;
  30     else
  31         last->next = new;
  32
  33     last = new;
  34
  35     return 0;
  36 }
  37
  38 int add_line(char *line) {
  39     if (strncmp(line, "dhcp-host=", 10) == 0 &&
  40                 line[12] == ':' && line[15] == ':' && line[18] == ':' && line[21] == ':' && line[24] == ':' &&
  41                 line[27] == ',') {
  42         char *ip, *nextip;
  43         char macstring[4];
  44         LINE *new = malloc(sizeof(LINE));
  45
  46         if (new == NULL) return -1;
  47
  48         listlen++;
  49         macstring[2] = '\0';
  50         macstring[3] = '\0';
  51
  52         new->mac = 0;
  53         new->ip  = 0;
  54         new->next= NULL;
  55
  56         strncpy(macstring, &line[19], 2);
  57         new->mac += (strtoul(macstring, NULL, 16) * (unsigned long int)(256 * 256));
  58         strncpy(macstring, &line[22], 2);
  59         new->mac += (strtoul(macstring, NULL, 16) * (unsigned long int)(256));
  60         strncpy(macstring, &line[25], 2);
  61         new->mac += (strtoul(macstring, NULL, 16));
  62
  63         ip = strchr(&line[28], ',');
  64         new->fqdn = strndup(&line[28], ip - &line[28]);
  65         ip++;
  66
  67         macstring[1] = '\0'; macstring[2] = '\0';
  68         strncpy(macstring, ip, (nextip = strchr(ip, '.')) - ip);
  69         new->ip += (strtoul(macstring, NULL, 10) * (unsigned long int)(256 * 256 * 256));
  70 //        printf("%s %lu\n",  macstring, new->ip);
  71         ip = nextip + 1;
  72
  73         macstring[1] = '\0'; macstring[2] = '\0';
  74         strncpy(macstring, ip, (nextip = strchr(ip, '.')) - ip);
  75         new->ip += (strtoul(macstring, NULL, 10) * (unsigned long int)(256 * 256));
  76 //        printf("%s %lu\n",  macstring, (strtoul(macstring, NULL, 10) * (unsigned long int)(256 * 256)));
  77         ip = nextip + 1;
  78
  79         macstring[1] = '\0'; macstring[2] = '\0';
  80         strncpy(macstring, ip, (nextip = strchr(ip, '.')) - ip);
  81         new->ip += (strtoul(macstring, NULL, 10) * (unsigned long int)(256));
  82 //        printf("%s %lu\n",  macstring, strtoul(macstring, NULL, 10) * (unsigned long int)(256));
  83         ip = nextip + 1;
  84
  85         macstring[1] = '\0'; macstring[2] = '\0';
  86         strncpy(macstring, ip, (nextip = strchr(ip, ',')) - ip);
  87         new->ip += (strtoul(macstring, NULL, 10));
  88 //        printf("%s %lu\n",  macstring, strtoul(macstring, NULL, 10));
  89
  90 //        printf("%06lX %s %lu %lu\n", new->mac, new->fqdn, new->mac, new->ip);
  91 //            dhcp-host=00:1E:C9:B3:B3:85,xen001.xen,172.16.103.1,24h
  92 //
  93
  94         if (!first)
  95             first = new;
  96         else
  97             last->next = new;
  98
  99         last = new;
 100
 101         return 0;
 102     }
 103
 104     return -1;
 105 }
 106
 107 char * print_mac(unsigned long int mac) {
 108     char *macstring = (char *) malloc(sizeof(char*) * 18);
 109     strcpy(macstring, "00:16:3E:");
 110     snprintf(&macstring[9], 8, "%06lX", mac);
 111     strncpy(&macstring[15], &macstring[13], 2);
 112     macstring[13] = macstring[12];
 113     macstring[12] = macstring[11];
 114     macstring[11] = ':';
 115     macstring[14] = ':';
 116     macstring[17] = '\0';
 117     return macstring;
 118 }
 119
 120 char * print_ip(unsigned long int ipaddress) {
 121     char *dest = (char *) malloc(sizeof(char*) * 16);
 122     int a, b, c, d;
 123     ldiv_t ip = ldiv(ipaddress, (256*256*256));
 124     a = ip.quot;
 125     ip = ldiv(ip.rem, (256*256));
 126     b = ip.quot;
 127     ip = ldiv(ip.rem, (256));
 128     c = ip.quot;
 129     d = ip.rem;
 130
 131     snprintf(dest, 16, "%d.%d.%d.%d", a, b, c, d);
 132     return dest;
 133 }
 134
 135 int print_forget(char *path) {
 136     FILE *fd = fopen(path, "w+");
 137
 138     LINE *step = first;
 139     while (step) {
 140         LINE *this = step;
 141         char *pretty_mac = print_mac(this->mac);
 142         char *pretty_ip  = print_ip(this->ip);
 143
 144         if (fd)
 145             fprintf(fd, "dhcp-host=%s,%s,%s,24h\n", pretty_mac, this->fqdn, pretty_ip);
 146
 147         free(pretty_mac);
 148         free(pretty_ip);
 149
 150         free(this->fqdn);
 151
 152         step = this->next;
 153         free(this);
 154     }
 155
 156     if (fd)
 157         fclose(fd);
 158
 159     return 0;
 160 }
 161
 162 int ll_array() {
 163     int i = 0;
 164     array = malloc(sizeof(LINE) * listlen);
 165
 166     LINE *step = first;
 167     while (step) {
 168         array[i].mac  = step->mac;
 169         array[i].ip  = step->ip;
 170         array[i].fqdn = step->fqdn;
 171         step = step->next;
 172         i++;
 173     }
 174
 175     return 0;
 176 }
 177
 178 static int bymac(const void *a, const void *b) {
 179     LINE *temp1 = (LINE *) a;
 180     LINE *temp2 = (LINE *) b;
 181
 182     return temp1->mac - temp2->mac;
 183 }
 184
 185 static int byip(const void *a, const void *b) {
 186     LINE *temp1 = (LINE *) a;
 187     LINE *temp2 = (LINE *) b;
 188
 189     return temp1->ip - temp2->ip;
 190 }
 191
 192 static unsigned long int nextmac() {
 193     int i;
 194     for (i = 0; i < (listlen - 1); i++) {
 195         if (array[i+1].mac != 0 && array[i+1].mac != array[i].mac + 1) return array[i].mac + 1;
 196     }
 197     return array[listlen - 1].mac + 1;
 198 }
 199
 200 static unsigned long int nextip() {
 201     int i;
 202     for (i = 0; i < (listlen - 1); i++) {
 203         if (array[i+1].ip != array[i].ip + 1) return array[i].ip + 1;
 204     }
 205     return array[listlen - 1].ip + 1;
 206 }
 207
 208 int getNewMac(char *cabinet, char *fqdn, char **mac, char **ip) {
 209     FILE *fd;
 210     char *pad = malloc(sizeof(char) * 128);
 211
 212     listlen = 0;
 213     first = NULL;
 214     last  = NULL;
 215     array   = NULL;
 216
 217     if (pad == NULL) return -1;
 218
 219     snprintf(pad, 128, "/mnt/netapp/ipservices/%s.conf", cabinet);
 220
 221     if ((fd = fopen(pad, "r")) != NULL) {
 222         char line[128];
 223         while (!feof(fd)) {
 224             if (fgets(line, 128, fd) > 0)
 225                 add_line(line);
 226         }
 227         fclose(fd);
 228     }
 229
 230     unsigned long int new_mac, new_ip;
 231     if (listlen == 0) {
 232         new_mac = 0;
 233         new_ip = 0;
 234     } else {
 235         ll_array();
 236
 237         qsort(array, listlen, sizeof(LINE), bymac);
 238         new_mac = nextmac();
 239
 240         qsort(array, listlen, sizeof(LINE), byip);
 241         new_ip = nextip();
 242     }
 243
 244     if (mac)
 245         *mac = print_mac(new_mac);
 246
 247     if (ip)
 248         *ip = print_ip(new_ip);
 249
 250     add(new_mac, new_ip, fqdn);
 251
 252     free(array);
 253
 254     print_forget(pad);
 255
 256     return 0;
 257
 258     free(pad);
 259 }
 260
 261 #ifdef WITH_MAIN
 262 int main(int argc, char *argv[]) {
 263     if (argc == 3) {
 264         getNewMac(argv[1], argv[2], NULL, NULL);
 265     }
 266     return 0;
 267 }
 268 #endif