experiment7.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 int add(LINE *first, LINE *last, unsigned long int mac, unsigned long int ip, char *fqdn) {
  16     LINE *new = malloc(sizeof(LINE));
  17     new->mac = mac;
  18     new->ip  = ip;
  19     new->fqdn = strdup(fqdn);
  20     new->next = NULL;
  21
  22     if (!first)
  23         first = new;
  24     else
  25         last->next = new;
  26
  27     last = new;
  28
  29     return 0;
  30 }
  31
  32 int add_line(LINE *first, LINE *last, char *line) {
  33     if (strncmp(line, "dhcp-host=", 10) == 0 &&
  34                 line[12] == ':' && line[15] == ':' && line[18] == ':' && line[21] == ':' && line[24] == ':' &&
  35                 line[27] == ',') {
  36         char *ip, *nextip;
  37         char macstring[4];
  38         LINE *new = malloc(sizeof(LINE));
  39
  40         if (new == NULL) return -1;
  41
  42         macstring[2] = '\0';
  43         macstring[3] = '\0';
  44
  45         new->mac = 0;
  46         new->ip  = 0;
  47         new->next= NULL;
  48
  49         strncpy(macstring, &line[19], 2);
  50         new->mac += (strtoul(macstring, NULL, 16) * (unsigned long int)(256 * 256));
  51         strncpy(macstring, &line[22], 2);
  52         new->mac += (strtoul(macstring, NULL, 16) * (unsigned long int)(256));
  53         strncpy(macstring, &line[25], 2);
  54         new->mac += (strtoul(macstring, NULL, 16));
  55
  56         ip = strchr(&line[28], ',');
  57         new->fqdn = strndup(&line[28], ip - &line[28]);
  58         printf("%s\n", new->fqdn);
  59         ip++;
  60
  61         macstring[1] = '\0'; macstring[2] = '\0';
  62         strncpy(macstring, ip, (nextip = strchr(ip, '.')) - ip);
  63         new->ip += (strtoul(macstring, NULL, 10) * (unsigned long int)(256 * 256 * 256));
  64 //        printf("%s %lu\n",  macstring, new->ip);
  65         ip = nextip + 1;
  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));
  70 //        printf("%s %lu\n",  macstring, (strtoul(macstring, NULL, 10) * (unsigned long int)(256 * 256)));
  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));
  76 //        printf("%s %lu\n",  macstring, strtoul(macstring, NULL, 10) * (unsigned long int)(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));
  82 //        printf("%s %lu\n",  macstring, strtoul(macstring, NULL, 10));
  83
  84 //        printf("%06lX %s %lu %lu\n", new->mac, new->fqdn, new->mac, new->ip);
  85 //            dhcp-host=00:1E:C9:B3:B3:85,xen001.xen,172.16.103.1,24h
  86 //
  87
  88         if (!first)
  89             first = new;
  90         else
  91             last->next = new;
  92
  93         last = new;
  94
  95         return 0;
  96     }
  97
  98     return -1;
  99 }
 100
 101 char * print_mac(unsigned long int mac) {
 102     char *macstring = (char *) malloc(sizeof(char*) * 18);
 103     strcpy(macstring, "00:16:3E:");
 104     snprintf(&macstring[9], 8, "%06lX", mac);
 105     strncpy(&macstring[15], &macstring[13], 2);
 106     macstring[13] = macstring[12];
 107     macstring[12] = macstring[11];
 108     macstring[11] = ':';
 109     macstring[14] = ':';
 110     macstring[17] = '\0';
 111     return macstring;
 112 }
 113
 114 char * print_ip(unsigned long int ipaddress) {
 115     char *dest = (char *) malloc(sizeof(char*) * 16);
 116     int a, b, c, d;
 117     ldiv_t ip = ldiv(ipaddress, (256*256*256));
 118     a = ip.quot;
 119     ip = ldiv(ip.rem, (256*256));
 120     b = ip.quot;
 121     ip = ldiv(ip.rem, (256));
 122     c = ip.quot;
 123     d = ip.rem;
 124
 125     snprintf(dest, 16, "%d.%d.%d.%d", a, b, c, d);
 126     return dest;
 127 }
 128
 129 int print_forget(LINE *first, char *path) {
 130     FILE *fd = fopen(path, "w");
 131
 132     LINE *step = first;
 133     while (step) {
 134         LINE *this = step;
 135         char *pretty_mac = print_mac(this->mac);
 136         char *pretty_ip  = print_ip(this->ip);
 137
 138         if (fd)
 139             fprintf(fd, "dhcp-host=%s,%s,%s,24h\n", pretty_mac, this->fqdn, pretty_ip);
 140
 141         free(pretty_mac);
 142         free(pretty_ip);
 143
 144         if (this->fqdn != NULL)
 145             free(this->fqdn);
 146
 147         step = this->next;
 148         free(this);
 149     }
 150
 151     if (fd) {
 152         fclose(fd);
 153         return 0;
 154     }
 155
 156     return -1;
 157 }
 158
 159 static int bymac(const void *a, const void *b) {
 160     LINE *temp1 = (LINE *) a;
 161     LINE *temp2 = (LINE *) b;
 162
 163     return temp1->mac - temp2->mac;
 164 }
 165
 166 static int byip(const void *a, const void *b) {
 167     LINE *temp1 = (LINE *) a;
 168     LINE *temp2 = (LINE *) b;
 169
 170     return temp1->ip - temp2->ip;
 171 }
 172
 173 static unsigned long int nextmac(LINE *array, int listlen) {
 174     int i;
 175     for (i = 0; i < (listlen - 1); i++) {
 176         if (array[i+1].mac != 0 && array[i+1].mac != array[i].mac + 1) return array[i].mac + 1;
 177     }
 178     return array[listlen - 1].mac + 1;
 179 }
 180
 181 static unsigned long int nextip(LINE *array, int listlen) {
 182     int i;
 183     for (i = 0; i < (listlen - 1); i++) {
 184         if (array[i+1].ip != array[i].ip + 1) return array[i].ip + 1;
 185     }
 186     return array[listlen - 1].ip + 1;
 187 }
 188
 189 int getNewMac(char *cabinet, char *fqdn, char **mac, char **ip) {
 190     if (fqdn == NULL)
 191         return -1;
 192
 193     char *pad = malloc(sizeof(char) * 128);
 194
 195     if (pad == NULL) return -1;
 196
 197     LINE *first = NULL, *last = NULL, *array = NULL;
 198     snprintf(pad, 128, "/mnt/netapp/ipservices/%s.conf", cabinet);
 199
 200     FILE *fd;
 201
 202     int listlen = 0;
 203
 204     if ((fd = fopen(pad, "r")) != NULL) {
 205         char line[128];
 206         while (!feof(fd)) {
 207             if (fgets(line, 128, fd) > 0)
 208                 if (add_line(first, last, line) == 0)
 209                     listlen++;
 210         }
 211         fclose(fd);
 212     }
 213
 214     if (listlen > 0) {
 215         array = malloc(sizeof(LINE) * listlen);
 216         if (array == NULL) {
 217             // TODO: cleanup
 218             free(pad);
 219             return -1;
 220         } else {
 221             int i = 0;
 222             LINE *step = first;
 223             while (step) {
 224                 printf("i = %d\n", i);
 225                 array[i].mac  = step->mac;
 226                 array[i].ip  = step->ip;
 227                 array[i].fqdn = step->fqdn;
 228                 step = step->next;
 229                 i++;
 230             }
 231         }
 232         unsigned long int new_mac, new_ip;
 233
 234         qsort(array, listlen, sizeof(LINE), bymac);
 235         new_mac = nextmac(array, listlen);
 236         if (mac)
 237             *mac = print_mac(new_mac);
 238
 239         qsort(array, listlen, sizeof(LINE), byip);
 240         new_ip = nextip(array, listlen);
 241
 242         if (ip)
 243             *ip = print_ip(new_ip);
 244
 245         add(first, last, new_mac, new_ip, fqdn);
 246
 247         free(array);
 248
 249         print_forget(first, pad);
 250
 251         free(pad);
 252         return 0;
 253     }
 254     free(pad);
 255
 256     return -1;
 257 }
 258
 259 #ifdef WITH_MAIN
 260 int main(int argc, char *argv[]) {
 261     if (argc == 3) {
 262         getNewMac(argv[1], argv[2], NULL, NULL);
 263     }
 264     return 0;
 265 }
 266 #endif