* Build udhcpc binary from source.
[grml-terminalserver.git] / udhcp / files.c
diff --git a/udhcp/files.c b/udhcp/files.c
new file mode 100644 (file)
index 0000000..73a3bbc
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@@ -0,0 +1,346 @@
+/*
+ * files.c -- DHCP server file manipulation *
+ * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
+ */
+
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <stdlib.h>
+#include <time.h>
+#include <ctype.h>
+#include <netdb.h>
+
+#include <netinet/ether.h>
+#include "static_leases.h"
+
+#include "dhcpd.h"
+#include "files.h"
+#include "options.h"
+#include "common.h"
+
+/*
+ * Domain names may have 254 chars, and string options can be 254
+ * chars long. However, 80 bytes will be enough for most, and won't
+ * hog up memory. If you have a special application, change it
+ */
+#define READ_CONFIG_BUF_SIZE 80
+
+/* on these functions, make sure you datatype matches */
+static int read_ip(const char *line, void *arg)
+{
+       struct in_addr *addr = arg;
+       struct hostent *host;
+       int retval = 1;
+
+       if (!inet_aton(line, addr)) {
+               if ((host = gethostbyname(line)))
+                       addr->s_addr = *((unsigned long *) host->h_addr_list[0]);
+               else retval = 0;
+       }
+       return retval;
+}
+
+static int read_mac(const char *line, void *arg)
+{
+       uint8_t *mac_bytes = arg;
+       struct ether_addr *temp_ether_addr;
+       int retval = 1;
+
+       temp_ether_addr = ether_aton(line);
+
+       if(temp_ether_addr == NULL)
+               retval = 0;
+       else
+               memcpy(mac_bytes, temp_ether_addr, 6);
+
+       return retval;
+}
+
+
+static int read_str(const char *line, void *arg)
+{
+       char **dest = arg;
+
+       if (*dest) free(*dest);
+       *dest = strdup(line);
+
+       return 1;
+}
+
+
+static int read_u32(const char *line, void *arg)
+{
+       uint32_t *dest = arg;
+       char *endptr;
+       *dest = strtoul(line, &endptr, 0);
+       return endptr[0] == '\0';
+}
+
+
+static int read_yn(const char *line, void *arg)
+{
+       char *dest = arg;
+       int retval = 1;
+
+       if (!strcasecmp("yes", line))
+               *dest = 1;
+       else if (!strcasecmp("no", line))
+               *dest = 0;
+       else retval = 0;
+
+       return retval;
+}
+
+
+/* read a dhcp option and add it to opt_list */
+static int read_opt(const char *const_line, void *arg)
+{
+       struct option_set **opt_list = arg;
+       char *opt, *val, *endptr;
+       struct dhcp_option *option;
+       int retval = 0, length;
+       char buffer[8];
+       char *line;
+       uint16_t *result_u16 = (uint16_t *) buffer;
+       uint32_t *result_u32 = (uint32_t *) buffer;
+
+       /* Cheat, the only const line we'll actually get is "" */
+       line = (char *) const_line;
+       if (!(opt = strtok(line, " \t="))) return 0;
+
+       for (option = dhcp_options; option->code; option++)
+               if (!strcasecmp(option->name, opt))
+                       break;
+
+       if (!option->code) return 0;
+
+       do {
+               if (!(val = strtok(NULL, ", \t"))) break;
+               length = option_lengths[option->flags & TYPE_MASK];
+               retval = 0;
+               opt = buffer; /* new meaning for variable opt */
+               switch (option->flags & TYPE_MASK) {
+               case OPTION_IP:
+                       retval = read_ip(val, buffer);
+                       break;
+               case OPTION_IP_PAIR:
+                       retval = read_ip(val, buffer);
+                       if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
+                       if (retval) retval = read_ip(val, buffer + 4);
+                       break;
+               case OPTION_STRING:
+                       length = strlen(val);
+                       if (length > 0) {
+                               if (length > 254) length = 254;
+                               opt = val;
+                               retval = 1;
+                       }
+                       break;
+               case OPTION_BOOLEAN:
+                       retval = read_yn(val, buffer);
+                       break;
+               case OPTION_U8:
+                       buffer[0] = strtoul(val, &endptr, 0);
+                       retval = (endptr[0] == '\0');
+                       break;
+               case OPTION_U16:
+                       *result_u16 = htons(strtoul(val, &endptr, 0));
+                       retval = (endptr[0] == '\0');
+                       break;
+               case OPTION_S16:
+                       *result_u16 = htons(strtol(val, &endptr, 0));
+                       retval = (endptr[0] == '\0');
+                       break;
+               case OPTION_U32:
+                       *result_u32 = htonl(strtoul(val, &endptr, 0));
+                       retval = (endptr[0] == '\0');
+                       break;
+               case OPTION_S32:
+                       *result_u32 = htonl(strtol(val, &endptr, 0));
+                       retval = (endptr[0] == '\0');
+                       break;
+               default:
+                       break;
+               }
+               if (retval)
+                       attach_option(opt_list, option, opt, length);
+       } while (retval && option->flags & OPTION_LIST);
+       return retval;
+}
+
+static int read_staticlease(const char *const_line, void *arg)
+{
+
+       char *line;
+       char *mac_string;
+       char *ip_string;
+       uint8_t *mac_bytes;
+       uint32_t *ip;
+
+
+       /* Allocate memory for addresses */
+       mac_bytes = xmalloc(sizeof(unsigned char) * 8);
+       ip = xmalloc(sizeof(uint32_t));
+
+       /* Read mac */
+       line = (char *) const_line;
+       mac_string = strtok(line, " \t");
+       read_mac(mac_string, mac_bytes);
+
+       /* Read ip */
+       ip_string = strtok(NULL, " \t");
+       read_ip(ip_string, ip);
+
+       addStaticLease(arg, mac_bytes, ip);
+
+#ifdef UDHCP_DEBUG
+       printStaticLeases(arg);
+#endif
+
+       return 1;
+
+}
+
+
+static const struct config_keyword keywords[] = {
+       /* keyword      handler   variable address              default */
+       {"start",       read_ip,  &(server_config.start),       "192.168.0.20"},
+       {"end",         read_ip,  &(server_config.end),         "192.168.0.254"},
+       {"interface",   read_str, &(server_config.interface),   "eth0"},
+       {"option",      read_opt, &(server_config.options),     ""},
+       {"opt",         read_opt, &(server_config.options),     ""},
+       {"max_leases",  read_u32, &(server_config.max_leases),  "254"},
+       {"remaining",   read_yn,  &(server_config.remaining),   "yes"},
+       {"auto_time",   read_u32, &(server_config.auto_time),   "7200"},
+       {"decline_time",read_u32, &(server_config.decline_time),"3600"},
+       {"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
+       {"offer_time",  read_u32, &(server_config.offer_time),  "60"},
+       {"min_lease",   read_u32, &(server_config.min_lease),   "60"},
+       {"lease_file",  read_str, &(server_config.lease_file),  LEASES_FILE},
+       {"pidfile",     read_str, &(server_config.pidfile),     "/var/run/udhcpd.pid"},
+       {"notify_file", read_str, &(server_config.notify_file), ""},
+       {"siaddr",      read_ip,  &(server_config.siaddr),      "0.0.0.0"},
+       {"sname",       read_str, &(server_config.sname),       ""},
+       {"boot_file",   read_str, &(server_config.boot_file),   ""},
+       {"static_lease",read_staticlease, &(server_config.static_leases),       ""},
+       /*ADDME: static lease */
+       {"",            NULL,     NULL,                         ""}
+};
+
+
+int read_config(const char *file)
+{
+       FILE *in;
+       char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
+#ifdef UDHCP_DEBUG
+       char orig[READ_CONFIG_BUF_SIZE];
+#endif
+       int i, lm = 0;
+
+       for (i = 0; keywords[i].keyword[0]; i++)
+               if (keywords[i].def[0])
+                       keywords[i].handler(keywords[i].def, keywords[i].var);
+
+       if (!(in = fopen(file, "r"))) {
+               LOG(LOG_ERR, "unable to open config file: %s", file);
+               return 0;
+       }
+
+       while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
+               lm++;
+               if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
+#ifdef UDHCP_DEBUG
+               strcpy(orig, buffer);
+#endif
+               if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';
+
+               if (!(token = strtok(buffer, " \t"))) continue;
+               if (!(line = strtok(NULL, ""))) continue;
+
+               /* eat leading whitespace */
+               line = line + strspn(line, " \t=");
+               /* eat trailing whitespace */
+               for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
+               line[i] = '\0';
+
+               for (i = 0; keywords[i].keyword[0]; i++)
+                       if (!strcasecmp(token, keywords[i].keyword))
+                               if (!keywords[i].handler(line, keywords[i].var)) {
+                                       LOG(LOG_ERR, "Failure parsing line %d of %s", lm, file);
+                                       DEBUG(LOG_ERR, "unable to parse '%s'", orig);
+                                       /* reset back to the default value */
+                                       keywords[i].handler(keywords[i].def, keywords[i].var);
+                               }
+       }
+       fclose(in);
+       return 1;
+}
+
+
+void write_leases(void)
+{
+       FILE *fp;
+       unsigned int i;
+       char buf[255];
+       time_t curr = time(0);
+       unsigned long tmp_time;
+
+       if (!(fp = fopen(server_config.lease_file, "w"))) {
+               LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file);
+               return;
+       }
+
+       for (i = 0; i < server_config.max_leases; i++) {
+               if (leases[i].yiaddr != 0) {
+
+                       /* screw with the time in the struct, for easier writing */
+                       tmp_time = leases[i].expires;
+
+                       if (server_config.remaining) {
+                               if (lease_expired(&(leases[i])))
+                                       leases[i].expires = 0;
+                               else leases[i].expires -= curr;
+                       } /* else stick with the time we got */
+                       leases[i].expires = htonl(leases[i].expires);
+                       fwrite(&leases[i], sizeof(struct dhcpOfferedAddr), 1, fp);
+
+                       /* Then restore it when done. */
+                       leases[i].expires = tmp_time;
+               }
+       }
+       fclose(fp);
+
+       if (server_config.notify_file) {
+               sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
+               system(buf);
+       }
+}
+
+
+void read_leases(const char *file)
+{
+       FILE *fp;
+       unsigned int i = 0;
+       struct dhcpOfferedAddr lease;
+
+       if (!(fp = fopen(file, "r"))) {
+               LOG(LOG_ERR, "Unable to open %s for reading", file);
+               return;
+       }
+
+       while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) {
+               /* ADDME: is it a static lease */
+               if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
+                       lease.expires = ntohl(lease.expires);
+                       if (!server_config.remaining) lease.expires -= time(0);
+                       if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
+                               LOG(LOG_WARNING, "Too many leases while loading %s\n", file);
+                               break;
+                       }
+                       i++;
+               }
+       }
+       DEBUG(LOG_INFO, "Read %d leases", i);
+       fclose(fp);
+}