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-rw-r--r--networking/udhcp/files.c413
1 files changed, 413 insertions, 0 deletions
diff --git a/networking/udhcp/files.c b/networking/udhcp/files.c
new file mode 100644
index 0000000..0b97d76
--- /dev/null
+++ b/networking/udhcp/files.c
@@ -0,0 +1,413 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * files.c -- DHCP server file manipulation *
+ * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
+ */
+
+#include <netinet/ether.h>
+
+#include "common.h"
+#include "dhcpd.h"
+#include "options.h"
+
+
+/* on these functions, make sure your datatype matches */
+static int read_ip(const char *line, void *arg)
+{
+ len_and_sockaddr *lsa;
+
+ lsa = host_and_af2sockaddr(line, 0, AF_INET);
+ if (!lsa)
+ return 0;
+ *(uint32_t*)arg = lsa->u.sin.sin_addr.s_addr;
+ free(lsa);
+ return 1;
+}
+
+static int read_mac(const char *line, void *arg)
+{
+ struct ether_addr *temp_ether_addr;
+
+ temp_ether_addr = ether_aton_r(line, (struct ether_addr *)arg);
+ if (temp_ether_addr == NULL)
+ return 0;
+ return 1;
+}
+
+
+static int read_str(const char *line, void *arg)
+{
+ char **dest = arg;
+
+ free(*dest);
+ *dest = xstrdup(line);
+ return 1;
+}
+
+
+static int read_u32(const char *line, void *arg)
+{
+ *(uint32_t*)arg = bb_strtou32(line, NULL, 10);
+ return errno == 0;
+}
+
+
+static int read_yn(const char *line, void *arg)
+{
+ char *dest = arg;
+
+ if (!strcasecmp("yes", line)) {
+ *dest = 1;
+ return 1;
+ }
+ if (!strcasecmp("no", line)) {
+ *dest = 0;
+ return 1;
+ }
+ return 0;
+}
+
+
+/* find option 'code' in opt_list */
+struct option_set* FAST_FUNC find_option(struct option_set *opt_list, uint8_t code)
+{
+ while (opt_list && opt_list->data[OPT_CODE] < code)
+ opt_list = opt_list->next;
+
+ if (opt_list && opt_list->data[OPT_CODE] == code)
+ return opt_list;
+ return NULL;
+}
+
+
+/* add an option to the opt_list */
+static void attach_option(struct option_set **opt_list,
+ const struct dhcp_option *option, char *buffer, int length)
+{
+ struct option_set *existing, *new, **curr;
+
+ existing = find_option(*opt_list, option->code);
+ if (!existing) {
+ DEBUG("Attaching option %02x to list", option->code);
+
+#if ENABLE_FEATURE_UDHCP_RFC3397
+ if ((option->flags & TYPE_MASK) == OPTION_STR1035)
+ /* reuse buffer and length for RFC1035-formatted string */
+ buffer = (char *)dname_enc(NULL, 0, buffer, &length);
+#endif
+
+ /* make a new option */
+ new = xmalloc(sizeof(*new));
+ new->data = xmalloc(length + 2);
+ new->data[OPT_CODE] = option->code;
+ new->data[OPT_LEN] = length;
+ memcpy(new->data + 2, buffer, length);
+
+ curr = opt_list;
+ while (*curr && (*curr)->data[OPT_CODE] < option->code)
+ curr = &(*curr)->next;
+
+ new->next = *curr;
+ *curr = new;
+#if ENABLE_FEATURE_UDHCP_RFC3397
+ if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL)
+ free(buffer);
+#endif
+ return;
+ }
+
+ /* add it to an existing option */
+ DEBUG("Attaching option %02x to existing member of list", option->code);
+ if (option->flags & OPTION_LIST) {
+#if ENABLE_FEATURE_UDHCP_RFC3397
+ if ((option->flags & TYPE_MASK) == OPTION_STR1035)
+ /* reuse buffer and length for RFC1035-formatted string */
+ buffer = (char *)dname_enc(existing->data + 2,
+ existing->data[OPT_LEN], buffer, &length);
+#endif
+ if (existing->data[OPT_LEN] + length <= 255) {
+ existing->data = xrealloc(existing->data,
+ existing->data[OPT_LEN] + length + 3);
+ if ((option->flags & TYPE_MASK) == OPTION_STRING) {
+ /* ' ' can bring us to 256 - bad */
+ if (existing->data[OPT_LEN] + length >= 255)
+ return;
+ /* add space separator between STRING options in a list */
+ existing->data[existing->data[OPT_LEN] + 2] = ' ';
+ existing->data[OPT_LEN]++;
+ }
+ memcpy(existing->data + existing->data[OPT_LEN] + 2, buffer, length);
+ existing->data[OPT_LEN] += length;
+ } /* else, ignore the data, we could put this in a second option in the future */
+#if ENABLE_FEATURE_UDHCP_RFC3397
+ if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL)
+ free(buffer);
+#endif
+ } /* else, ignore the new data */
+}
+
+
+/* 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;
+ char *line;
+ const struct dhcp_option *option;
+ int retval, length, idx;
+ char buffer[8] ALIGNED(4);
+ 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;
+ opt = strtok(line, " \t=");
+ if (!opt)
+ return 0;
+
+ idx = index_in_strings(dhcp_option_strings, opt); /* NB: was strcasecmp! */
+ if (idx < 0)
+ return 0;
+ option = &dhcp_options[idx];
+
+ retval = 0;
+ do {
+ val = strtok(NULL, ", \t");
+ if (!val) break;
+ length = dhcp_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);
+ val = strtok(NULL, ", \t/-");
+ if (!val)
+ retval = 0;
+ if (retval)
+ retval = read_ip(val, buffer + 4);
+ break;
+ case OPTION_STRING:
+#if ENABLE_FEATURE_UDHCP_RFC3397
+ case OPTION_STR1035:
+#endif
+ 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;
+ /* htonX are macros in older libc's, using temp var
+ * in code below for safety */
+ /* TODO: use bb_strtoX? */
+ case OPTION_U16: {
+ unsigned long tmp = strtoul(val, &endptr, 0);
+ *result_u16 = htons(tmp);
+ retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
+ break;
+ }
+ case OPTION_S16: {
+ long tmp = strtol(val, &endptr, 0);
+ *result_u16 = htons(tmp);
+ retval = (endptr[0] == '\0');
+ break;
+ }
+ case OPTION_U32: {
+ unsigned long tmp = strtoul(val, &endptr, 0);
+ *result_u32 = htonl(tmp);
+ retval = (endptr[0] == '\0');
+ break;
+ }
+ case OPTION_S32: {
+ long tmp = strtol(val, &endptr, 0);
+ *result_u32 = htonl(tmp);
+ 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);
+
+ if (ENABLE_UDHCP_DEBUG) printStaticLeases(arg);
+
+ return 1;
+}
+
+
+struct config_keyword {
+ const char *keyword;
+ int (*handler)(const char *line, void *var);
+ void *var;
+ const char *def;
+};
+
+static const struct config_keyword keywords[] = {
+ /* keyword handler variable address default */
+ {"start", read_ip, &(server_config.start_ip), "192.168.0.20"},
+ {"end", read_ip, &(server_config.end_ip), "192.168.0.254"},
+ {"interface", read_str, &(server_config.interface), "eth0"},
+ /* Avoid "max_leases value not sane" warning by setting default
+ * to default_end_ip - default_start_ip + 1: */
+ {"max_leases", read_u32, &(server_config.max_leases), "235"},
+ {"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"},
+ {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
+ /* keywords with no defaults must be last! */
+ {"option", read_opt, &(server_config.options), ""},
+ {"opt", read_opt, &(server_config.options), ""},
+ {"notify_file", read_str, &(server_config.notify_file), ""},
+ {"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 */
+};
+enum { KWS_WITH_DEFAULTS = ARRAY_SIZE(keywords) - 6 };
+
+void FAST_FUNC read_config(const char *file)
+{
+ parser_t *parser;
+ const struct config_keyword *k;
+ unsigned i;
+ char *token[2];
+
+ for (i = 0; i < KWS_WITH_DEFAULTS; i++)
+ keywords[i].handler(keywords[i].def, keywords[i].var);
+
+ parser = config_open(file);
+ while (config_read(parser, token, 2, 2, "# \t", PARSE_NORMAL)) {
+ for (k = keywords, i = 0; i < ARRAY_SIZE(keywords); k++, i++) {
+ if (!strcasecmp(token[0], k->keyword)) {
+ if (!k->handler(token[1], k->var)) {
+ bb_error_msg("can't parse line %u in %s",
+ parser->lineno, file);
+ /* reset back to the default value */
+ k->handler(k->def, k->var);
+ }
+ break;
+ }
+ }
+ }
+ config_close(parser);
+
+ server_config.start_ip = ntohl(server_config.start_ip);
+ server_config.end_ip = ntohl(server_config.end_ip);
+}
+
+
+void FAST_FUNC write_leases(void)
+{
+ int fp;
+ unsigned i;
+ time_t curr = time(0);
+ unsigned long tmp_time;
+
+ fp = open_or_warn(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC);
+ if (fp < 0) {
+ 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);
+ // FIXME: error check??
+ full_write(fp, &leases[i], sizeof(leases[i]));
+
+ /* then restore it when done */
+ leases[i].expires = tmp_time;
+ }
+ }
+ close(fp);
+
+ if (server_config.notify_file) {
+// TODO: vfork-based child creation
+ char *cmd = xasprintf("%s %s", server_config.notify_file, server_config.lease_file);
+ system(cmd);
+ free(cmd);
+ }
+}
+
+
+void FAST_FUNC read_leases(const char *file)
+{
+ int fp;
+ unsigned i;
+ struct dhcpOfferedAddr lease;
+
+ fp = open_or_warn(file, O_RDONLY);
+ if (fp < 0) {
+ return;
+ }
+
+ i = 0;
+ while (i < server_config.max_leases
+ && full_read(fp, &lease, sizeof(lease)) == sizeof(lease)
+ ) {
+ /* ADDME: is it a static lease */
+ uint32_t y = ntohl(lease.yiaddr);
+ if (y >= server_config.start_ip && y <= server_config.end_ip) {
+ lease.expires = ntohl(lease.expires);
+ if (!server_config.remaining)
+ lease.expires -= time(NULL);
+ if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
+ bb_error_msg("too many leases while loading %s", file);
+ break;
+ }
+ i++;
+ }
+ }
+ DEBUG("Read %d leases", i);
+ close(fp);
+}