dhcpv6-ia: make tmp lease file hidden

[project/odhcpd.git] / src / dhcpv6-ia.c

diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index e8255b5c0381a45b6cbe8d6bf8bd43725430af93..99fd2fda61cab453158ef8e4ea05fe903d210994 100644 (file)
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -28,6 +28,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <libgen.h>
 #include <stdbool.h>
 #include <arpa/inet.h>
 #include <sys/timerfd.h>
@@ -320,13 +321,29 @@ void dhcpv6_ia_write_statefile(void)
        md5_begin(&ctxt.md5);
 
        if (config.dhcp_statefile) {
-               unsigned tmp_statefile_strlen = strlen(config.dhcp_statefile) + strlen(".tmp") + 1;
+               unsigned statefile_strlen = strlen(config.dhcp_statefile) + 1;
+               unsigned tmp_statefile_strlen = statefile_strlen + 1; /* space for . */
                char *tmp_statefile = alloca(tmp_statefile_strlen);
+
+               char *dir_statefile;
+               char *base_statefile;
+               char *pdir_statefile;
+               char *pbase_statefile;
+
                time_t now = odhcpd_time(), wall_time = time(NULL);
                int fd, ret;
                char leasebuf[512];
 
-               snprintf(tmp_statefile, tmp_statefile_strlen, "%s.tmp", config.dhcp_statefile);
+               dir_statefile = strndup(config.dhcp_statefile, statefile_strlen);
+               base_statefile = strndup(config.dhcp_statefile, statefile_strlen);
+
+               pdir_statefile = dirname(dir_statefile);
+               pbase_statefile = basename(base_statefile);
+
+               snprintf(tmp_statefile, tmp_statefile_strlen, "%s/.%s", pdir_statefile, pbase_statefile);
+
+               free(dir_statefile);
+               free(base_statefile);
 
                fd = open(tmp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
                if (fd < 0)
@@ -437,18 +454,22 @@ void dhcpv6_ia_write_statefile(void)
 
                fclose(ctxt.fp);
 
-               rename(tmp_statefile, config.dhcp_statefile);
-       }
+               uint8_t newmd5[16];
+               md5_end(newmd5, &ctxt.md5);
 
-       uint8_t newmd5[16];
-       md5_end(newmd5, &ctxt.md5);
+               if (memcmp(newmd5, statemd5, sizeof(newmd5))) {
+                       memcpy(statemd5, newmd5, sizeof(statemd5));
+                       rename(tmp_statefile, config.dhcp_statefile);
 
-       if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
-               memcpy(statemd5, newmd5, sizeof(statemd5));
-               char *argv[2] = {config.dhcp_cb, NULL};
-               if (!vfork()) {
-                       execv(argv[0], argv);
-                       _exit(128);
+                       if (config.dhcp_cb) {
+                               char *argv[2] = {config.dhcp_cb, NULL};
+                               if (!vfork()) {
+                                       execv(argv[0], argv);
+                                       _exit(128);
+                               }
+                       }
+               } else {
+                       unlink(tmp_statefile);
                }
        }
 }