+/* vi: set sw=4 ts=4: */
/*
- * files.c -- DHCP server file manipulation *
+ * DHCP server config and lease file manipulation
+ *
* Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
*/
-
-#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 "options.h"
-#include "files.h"
#include "common.h"
+#include "dhcpd.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)
+/* on these functions, make sure your datatype matches */
+static int FAST_FUNC read_str(const char *line, void *arg)
{
char **dest = arg;
- if (*dest) free(*dest);
- *dest = strdup(line);
-
+ free(*dest);
+ *dest = xstrdup(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;
-}
-
-
-/* find option 'code' in opt_list */
-struct option_set *find_option(struct option_set *opt_list, char 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;
- else return NULL;
-}
-
-
-/* add an option to the opt_list */
-static void attach_option(struct option_set **opt_list, struct dhcp_option *option, char *buffer, int length)
-{
- struct option_set *existing, *new, **curr;
-
- /* add it to an existing option */
- if ((existing = find_option(*opt_list, option->code))) {
- DEBUG(LOG_INFO, "Attaching option %s to existing member of list", option->name);
- if (option->flags & OPTION_LIST) {
- if (existing->data[OPT_LEN] + length <= 255) {
- existing->data = realloc(existing->data,
- existing->data[OPT_LEN] + length + 2);
- 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 */
- } /* else, ignore the new data */
- } else {
- DEBUG(LOG_INFO, "Attaching option %s to list", option->name);
-
- /* make a new option */
- new = xmalloc(sizeof(struct option_set));
- 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;
- }
-}
-
-/* read a dhcp option and add it to opt_list */
-static int read_opt(const char *const_line, void *arg)
+static int FAST_FUNC read_u32(const char *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;
+ *(uint32_t*)arg = bb_strtou32(line, NULL, 10);
+ return errno == 0;
}
-static int read_staticlease(const char *const_line, void *arg)
+static int FAST_FUNC 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));
+ struct ether_addr mac_bytes; /* it's "struct { uint8_t mac[6]; }" */
+ uint32_t nip;
/* Read mac */
line = (char *) const_line;
- mac_string = strtok(line, " \t");
- read_mac(mac_string, mac_bytes);
+ mac_string = strtok_r(line, " \t", &line);
+ if (!mac_string || !ether_aton_r(mac_string, &mac_bytes))
+ return 0;
/* Read ip */
- ip_string = strtok(NULL, " \t");
- read_ip(ip_string, ip);
+ ip_string = strtok_r(NULL, " \t", &line);
+ if (!ip_string || !udhcp_str2nip(ip_string, &nip))
+ return 0;
- addStaticLease(arg, mac_bytes, ip);
+ add_static_lease(arg, (uint8_t*) &mac_bytes, nip);
-#ifdef UDHCP_DEBUG
- printStaticLeases(arg);
-#endif
+ log_static_leases(arg);
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, ""}
+struct config_keyword {
+ const char *keyword;
+ int (*handler)(const char *line, void *var) FAST_FUNC;
+ void *var;
+ const char *def;
};
+static const struct config_keyword keywords[] = {
+ /* keyword handler variable address default */
+ {"start" , udhcp_str2nip , &server_config.start_ip , "192.168.0.20"},
+ {"end" , udhcp_str2nip , &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"},
+ {"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_sec, "60"},
+ {"lease_file" , read_str , &server_config.lease_file , LEASES_FILE},
+ {"pidfile" , read_str , &server_config.pidfile , "/var/run/udhcpd.pid"},
+ {"siaddr" , udhcp_str2nip , &server_config.siaddr_nip , "0.0.0.0"},
+ /* keywords with no defaults must be last! */
+ {"option" , udhcp_str2optset, &server_config.options , ""},
+ {"opt" , udhcp_str2optset, &server_config.options , ""},
+ {"notify_file" , read_str , &server_config.notify_file , NULL},
+ {"sname" , read_str , &server_config.sname , NULL},
+ {"boot_file" , read_str , &server_config.boot_file , NULL},
+ {"static_lease" , read_staticlease, &server_config.static_leases, ""},
+};
+enum { KWS_WITH_DEFAULTS = ARRAY_SIZE(keywords) - 6 };
-int read_config(const char *file)
+void FAST_FUNC 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);
+ 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) == 0) {
+ 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 */
- keywords[i].handler(keywords[i].def, keywords[i].var);
+ k->handler(k->def, k->var);
}
+ break;
+ }
+ }
}
- fclose(in);
- return 1;
-}
+ config_close(parser);
+ server_config.start_ip = ntohl(server_config.start_ip);
+ server_config.end_ip = ntohl(server_config.end_ip);
+}
-void write_leases(void)
+void FAST_FUNC 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);
+ int fd;
+ unsigned i;
+ leasetime_t curr;
+ int64_t written_at;
+
+ fd = open_or_warn(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC);
+ if (fd < 0)
return;
- }
+
+ curr = written_at = time(NULL);
+
+ written_at = SWAP_BE64(written_at);
+ full_write(fd, &written_at, sizeof(written_at));
for (i = 0; i < server_config.max_leases; i++) {
- if (leases[i].yiaddr != 0) {
+ leasetime_t tmp_time;
- /* screw with the time in the struct, for easier writing */
- tmp_time = leases[i].expires;
+ if (g_leases[i].lease_nip == 0)
+ continue;
- 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);
+ /* Screw with the time in the struct, for easier writing */
+ tmp_time = g_leases[i].expires;
- /* Then restore it when done. */
- leases[i].expires = tmp_time;
- }
+ g_leases[i].expires -= curr;
+ if ((signed_leasetime_t) g_leases[i].expires < 0)
+ g_leases[i].expires = 0;
+ g_leases[i].expires = htonl(g_leases[i].expires);
+
+ /* No error check. If the file gets truncated,
+ * we lose some leases on restart. Oh well. */
+ full_write(fd, &g_leases[i], sizeof(g_leases[i]));
+
+ /* Then restore it when done */
+ g_leases[i].expires = tmp_time;
}
- fclose(fp);
+ close(fd);
if (server_config.notify_file) {
- sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
- system(buf);
+ char *argv[3];
+ argv[0] = server_config.notify_file;
+ argv[1] = server_config.lease_file;
+ argv[2] = NULL;
+ spawn_and_wait(argv);
}
}
-
-void read_leases(const char *file)
+void FAST_FUNC read_leases(const char *file)
{
- FILE *fp;
- unsigned int i = 0;
- struct dhcpOfferedAddr lease;
+ struct dyn_lease lease;
+ int64_t written_at, time_passed;
+ int fd;
+#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
+ unsigned i = 0;
+#endif
- if (!(fp = fopen(file, "r"))) {
- LOG(LOG_ERR, "Unable to open %s for reading", file);
+ fd = open_or_warn(file, O_RDONLY);
+ if (fd < 0)
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);
+ if (full_read(fd, &written_at, sizeof(written_at)) != sizeof(written_at))
+ goto ret;
+ written_at = SWAP_BE64(written_at);
+
+ time_passed = time(NULL) - written_at;
+ /* Strange written_at, or lease file from old version of udhcpd
+ * which had no "written_at" field? */
+ if ((uint64_t)time_passed > 12 * 60 * 60)
+ goto ret;
+
+ while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) {
+//FIXME: what if it matches some static lease?
+ uint32_t y = ntohl(lease.lease_nip);
+ if (y >= server_config.start_ip && y <= server_config.end_ip) {
+ signed_leasetime_t expires = ntohl(lease.expires) - (signed_leasetime_t)time_passed;
+ if (expires <= 0)
+ continue;
+ /* NB: add_lease takes "relative time", IOW,
+ * lease duration, not lease deadline. */
+ if (add_lease(lease.lease_mac, lease.lease_nip,
+ expires,
+ lease.hostname, sizeof(lease.hostname)
+ ) == 0
+ ) {
+ bb_error_msg("too many leases while loading %s", file);
break;
}
+#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
i++;
+#endif
}
}
- DEBUG(LOG_INFO, "Read %d leases", i);
- fclose(fp);
+ log1("Read %d leases", i);
+ ret:
+ close(fd);
}
projects / oweals / busybox.git / blobdiff