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authorDenys Vlasenko2016-10-04 00:37:50 +0200
committerDenys Vlasenko2016-10-04 00:56:58 +0200
commit2bf2931d526fbd3998b9ffe99cdbad5d5ea6d290 (patch)
treeb3a9944d558acea501d9b06b8221b6b45ba4a787 /networking/udhcp/dhcpd.c
parent095ddf7669a05b52839ccbfd2c324de718241747 (diff)
downloadbusybox-2bf2931d526fbd3998b9ffe99cdbad5d5ea6d290.zip
busybox-2bf2931d526fbd3998b9ffe99cdbad5d5ea6d290.tar.gz
dhcp: merge files.c into dhcpd.c
Added NOINLINE to two function, since my version of gcc would actualy increase code size otherwise. I see no size changes. Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'networking/udhcp/dhcpd.c')
-rw-r--r--networking/udhcp/dhcpd.c223
1 files changed, 221 insertions, 2 deletions
diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index e93a9f1..8bd65df 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -33,11 +33,232 @@
//usage: "\n -P N Use port N (default 67)"
//usage: )
+#include <netinet/ether.h>
#include <syslog.h>
#include "common.h"
#include "dhcpc.h"
#include "dhcpd.h"
+/* on these functions, make sure your datatype matches */
+static int FAST_FUNC read_str(const char *line, void *arg)
+{
+ char **dest = arg;
+
+ free(*dest);
+ *dest = xstrdup(line);
+ return 1;
+}
+
+static int FAST_FUNC read_u32(const char *line, void *arg)
+{
+ *(uint32_t*)arg = bb_strtou32(line, NULL, 10);
+ return errno == 0;
+}
+
+static int FAST_FUNC read_staticlease(const char *const_line, void *arg)
+{
+ char *line;
+ char *mac_string;
+ char *ip_string;
+ struct ether_addr mac_bytes; /* it's "struct { uint8_t mac[6]; }" */
+ uint32_t nip;
+
+ /* Read mac */
+ line = (char *) const_line;
+ mac_string = strtok_r(line, " \t", &line);
+ if (!mac_string || !ether_aton_r(mac_string, &mac_bytes))
+ return 0;
+
+ /* Read ip */
+ ip_string = strtok_r(NULL, " \t", &line);
+ if (!ip_string || !udhcp_str2nip(ip_string, &nip))
+ return 0;
+
+ add_static_lease(arg, (uint8_t*) &mac_bytes, nip);
+
+ log_static_leases(arg);
+
+ return 1;
+}
+
+struct config_keyword {
+ const char *keyword;
+ int (*handler)(const char *line, void *var) FAST_FUNC;
+ unsigned ofs;
+ const char *def;
+};
+
+#define OFS(field) offsetof(struct server_config_t, field)
+
+static const struct config_keyword keywords[] = {
+ /* keyword handler variable address default */
+ {"start" , udhcp_str2nip , OFS(start_ip ), "192.168.0.20"},
+ {"end" , udhcp_str2nip , OFS(end_ip ), "192.168.0.254"},
+ {"interface" , read_str , OFS(interface ), "eth0"},
+ /* Avoid "max_leases value not sane" warning by setting default
+ * to default_end_ip - default_start_ip + 1: */
+ {"max_leases" , read_u32 , OFS(max_leases ), "235"},
+ {"auto_time" , read_u32 , OFS(auto_time ), "7200"},
+ {"decline_time" , read_u32 , OFS(decline_time ), "3600"},
+ {"conflict_time", read_u32 , OFS(conflict_time), "3600"},
+ {"offer_time" , read_u32 , OFS(offer_time ), "60"},
+ {"min_lease" , read_u32 , OFS(min_lease_sec), "60"},
+ {"lease_file" , read_str , OFS(lease_file ), LEASES_FILE},
+ {"pidfile" , read_str , OFS(pidfile ), "/var/run/udhcpd.pid"},
+ {"siaddr" , udhcp_str2nip , OFS(siaddr_nip ), "0.0.0.0"},
+ /* keywords with no defaults must be last! */
+ {"option" , udhcp_str2optset, OFS(options ), ""},
+ {"opt" , udhcp_str2optset, OFS(options ), ""},
+ {"notify_file" , read_str , OFS(notify_file ), NULL},
+ {"sname" , read_str , OFS(sname ), NULL},
+ {"boot_file" , read_str , OFS(boot_file ), NULL},
+ {"static_lease" , read_staticlease, OFS(static_leases), ""},
+};
+enum { KWS_WITH_DEFAULTS = ARRAY_SIZE(keywords) - 6 };
+
+static NOINLINE void 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, (char*)&server_config + keywords[i].ofs);
+
+ 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], (char*)&server_config + k->ofs)) {
+ bb_error_msg("can't parse line %u in %s",
+ parser->lineno, file);
+ /* reset back to the default value */
+ k->handler(k->def, (char*)&server_config + k->ofs);
+ }
+ break;
+ }
+ }
+ }
+ config_close(parser);
+
+ server_config.start_ip = ntohl(server_config.start_ip);
+ server_config.end_ip = ntohl(server_config.end_ip);
+}
+
+static void write_leases(void)
+{
+ 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++) {
+ leasetime_t tmp_time;
+
+ if (g_leases[i].lease_nip == 0)
+ continue;
+
+ /* Screw with the time in the struct, for easier writing */
+ tmp_time = g_leases[i].expires;
+
+ 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;
+ }
+ close(fd);
+
+ if (server_config.notify_file) {
+ char *argv[3];
+ argv[0] = server_config.notify_file;
+ argv[1] = server_config.lease_file;
+ argv[2] = NULL;
+ spawn_and_wait(argv);
+ }
+}
+
+static NOINLINE void read_leases(const char *file)
+{
+ 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
+
+ fd = open_or_warn(file, O_RDONLY);
+ if (fd < 0)
+ return;
+
+ 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)) {
+ 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;
+ uint32_t static_nip;
+
+ if (expires <= 0)
+ /* We keep expired leases: add_lease() will add
+ * a lease with 0 seconds remaining.
+ * Fewer IP address changes this way for mass reboot scenario.
+ */
+ expires = 0;
+
+ /* Check if there is a different static lease for this IP or MAC */
+ static_nip = get_static_nip_by_mac(server_config.static_leases, lease.lease_mac);
+ if (static_nip) {
+ /* NB: we do not add lease even if static_nip == lease.lease_nip.
+ */
+ continue;
+ }
+ if (is_nip_reserved(server_config.static_leases, lease.lease_nip))
+ 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
+ }
+ }
+ log1("read %d leases", i);
+ ret:
+ close(fd);
+}
/* Send a packet to a specific mac address and ip address by creating our own ip packet */
static void send_packet_to_client(struct dhcp_packet *dhcp_pkt, int force_broadcast)
@@ -290,12 +511,10 @@ static NOINLINE void send_inform(struct dhcp_packet *oldpacket)
send_packet(&packet, /*force_bcast:*/ 0);
}
-
/* globals */
struct dyn_lease *g_leases;
/* struct server_config_t server_config is in bb_common_bufsiz1 */
-
int udhcpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int udhcpd_main(int argc UNUSED_PARAM, char **argv)
{