[v4_1_esv] Restores use of env vars for lease and pid files

    Merges in rt46859

3 files changed, 66 insertions, 69 deletions

diff --git a/RELNOTES b/RELNOTES
index 9fd6c005..fcade4c6 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -92,6 +92,14 @@ dhcp-users@lists.isc.org.
   completion of the test.
   [ISC-Bugs #22267]
 
+- The server now recognizes environment variables PATH_DHCPD_DB and
+  PATH_DHCPD_PID.  These had been incorrectly compiled out of the code
+  unless DHCPv6 support was disabled. Additionally, the server man
+  pages were corrected to accurately reflect how the server chooses
+  file names (see lease-file-name and pid-file-name statements). Thanks
+  to Fernando Soto at Bluecat for bringing this matter to our attention.
+  [ISC-Bugs #46859]
+
 			Changes since 4.1-ESV-R15b1
 
 - None
diff --git a/server/dhcpd.c b/server/dhcpd.c
index b5189ce3..5e593593 100644
--- a/server/dhcpd.c
+++ b/server/dhcpd.c
@@ -300,9 +300,9 @@ main(int argc, char **argv) {
 	struct interface_info *ip;
 	struct parse *parse;
 	int lose;
-	int no_dhcpd_conf = 0;
-	int no_dhcpd_db = 0;
-	int no_dhcpd_pid = 0;
+	int have_dhcpd_conf = 0;
+	int have_dhcpd_db = 0;
+	int have_dhcpd_pid = 0;
 #ifdef DHCPv6
 	int local_family_set = 0;
 #endif /* DHCPv6 */
@@ -401,17 +401,17 @@ main(int argc, char **argv) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_conf = argv [i];
-			no_dhcpd_conf = 1;
+			have_dhcpd_conf = 1;
 		} else if (!strcmp (argv [i], "-lf")) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_db = argv [i];
-			no_dhcpd_db = 1;
+			have_dhcpd_db = 1;
 		} else if (!strcmp (argv [i], "-pf")) {
 			if (++i == argc)
 				usage(use_noarg, argv[i-1]);
 			path_dhcpd_pid = argv [i];
-			no_dhcpd_pid = 1;
+			have_dhcpd_pid = 1;
 		} else if (!strcmp(argv[i], "--no-pid")) {
 			no_pid_file = ISC_TRUE;
                 } else if (!strcmp (argv [i], "-t")) {
@@ -487,42 +487,41 @@ main(int argc, char **argv) {
 		}
 	}
 
-	if (!no_dhcpd_conf && (s = getenv ("PATH_DHCPD_CONF"))) {
+	if (!have_dhcpd_conf && (s = getenv ("PATH_DHCPD_CONF"))) {
 		path_dhcpd_conf = s;
 	}
 
 #ifdef DHCPv6
         if (local_family == AF_INET6) {
                 /* DHCPv6: override DHCPv4 lease and pid filenames */
-	        if (!no_dhcpd_db) {
+	        if (!have_dhcpd_db) {
                         if ((s = getenv ("PATH_DHCPD6_DB")))
 		                path_dhcpd_db = s;
                         else
 		                path_dhcpd_db = _PATH_DHCPD6_DB;
 	        }
-	        if (!no_dhcpd_pid) {
+	        if (!have_dhcpd_pid) {
                         if ((s = getenv ("PATH_DHCPD6_PID")))
 		                path_dhcpd_pid = s;
                         else
 		                path_dhcpd_pid = _PATH_DHCPD6_PID;
 	        }
         } else
-#else /* !DHCPv6 */
+#endif /* DHCPv6 */
         {
-	        if (!no_dhcpd_db && (s = getenv ("PATH_DHCPD_DB"))) {
+	        if (!have_dhcpd_db && (s = getenv ("PATH_DHCPD_DB"))) {
 		        path_dhcpd_db = s;
 	        }
-	        if (!no_dhcpd_pid && (s = getenv ("PATH_DHCPD_PID"))) {
+	        if (!have_dhcpd_pid && (s = getenv ("PATH_DHCPD_PID"))) {
 		        path_dhcpd_pid = s;
 	        }
         }
-#endif /* DHCPv6 */
 
         /*
          * convert relative path names to absolute, for files that need
          * to be reopened after chdir() has been called
          */
-        if (path_dhcpd_db[0] != '/') {
+        if (have_dhcpd_db && path_dhcpd_db[0] != '/') {
                 char *path = dmalloc(PATH_MAX, MDL);
                 if (path == NULL)
                         log_fatal("No memory for filename\n");
@@ -702,7 +701,7 @@ main(int argc, char **argv) {
 
 #if defined (TRACING)
 	if (traceinfile) {
-	    if (!no_dhcpd_db) {
+	    if (!have_dhcpd_db) {
 		    log_error ("%s", "");
 		    log_error ("** You must specify a lease file with -lf.");
 		    log_error ("   Dhcpd will not overwrite your default");
diff --git a/server/dhcpd.conf.5 b/server/dhcpd.conf.5
index 50d1263a..2c4d78dd 100644
--- a/server/dhcpd.conf.5
+++ b/server/dhcpd.conf.5
@@ -1,6 +1,6 @@
 .\"	dhcpd.conf.5
 .\"
-.\" Copyright (c) 2004-2016 by Internet Systems Consortium, Inc. ("ISC")
+.\" Copyright (c) 2004-2017 by Internet Systems Consortium, Inc. ("ISC")
 .\" Copyright (c) 1996-2003 by Internet Software Consortium
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
@@ -2383,15 +2383,35 @@ statement
 .B lease-file-name \fIname\fB;\fR
 .PP
 .I Name
-should be the name of the DHCP server's lease file.  By default, this
-is DBDIR/dhcpd.leases.  This statement \fBmust\fR appear in the outer
-scope of the configuration file - if it appears in some other scope,
-it will have no effect.  Furthermore, it has no effect if overridden
-by the
-.B -lf
-flag or the
-.B PATH_DHCPD_DB
-environment variable.
+Where \fIname\fR is the name of the DHCP server's lease file. By default,
+this is DBDIR/dhcpd.leases.  This statement \fBmust\fR appear in the outer
+scope of the configuration file - if it appears in some other scope, it will
+have no effect.  The value must be the absolute path of the file to use.
+The order of precedence the server uses for the lease file name
+is:
+.PP
+    1. \fBlease-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD_DB\fR environment variable.
+.RE
+.PP
+The
+.I dhcpv6-lease-file-name
+statement
+.RS 0.25i
+.PP
+.B dhcpv6-lease-file-name \fIname\fB;\fR
+.PP
+Where \fIname\fR is the name of the DHCP server's lease file when the server
+is running DHCPv6. By default, this is DBDIR/dhcpd6.leases. This statement
+\fBmust\fR appear in the outer scope of the configuration file - if it appears
+in some other scope, it will have no effect.  The value must be the absolute
+path of the file to use.  The order of precedence the server uses
+for the lease file name is:
+.PP
+    1. \fBdhcpv6-lease-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD6_DB\fR environment variable.
 .RE
 .PP
 The
@@ -2411,30 +2431,6 @@ This is left to future work.
 .RE
 .PP
 The
-.I dhcpv6-lease-file-name
-statement
-.RS 0.25i
-.PP
-.B dhcpv6-lease-file-name \fIname\fB;\fR
-.PP
-.I Name
-is the name of the lease file to use if and only if the server is running
-in DHCPv6 mode.  By default, this is DBDIR/dhcpd6.leases.  This statement,
-like
-.I lease-file-name,
-\fBmust\fR appear in the outer scope of the configuration file.  It
-has no effect if overridden by the
-.B -lf
-flag or the
-.B PATH_DHCPD6_DB
-environment variable.  If
-.I dhcpv6-lease-file-name
-is not specified, but
-.I lease-file-name
-is, the latter value will be used.
-.RE
-.PP
-The
 .I local-port
 statement
 .RS 0.25i
@@ -2627,14 +2623,14 @@ statement
 .I Name
 should be the name of the DHCP server's process ID file.  This is the
 file in which the DHCP server's process ID is stored when the server
-starts.  By default, this is RUNDIR/dhcpd.pid.  Like the
-.I lease-file-name
-statement, this statement must appear in the outer scope
-of the configuration file.  It has no effect if overridden by the
-.B -pf
-flag or the
-.B PATH_DHCPD_PID
-environment variable.
+starts.  By default, this is RUNDIR/dhcpd.pid.  Like the \fIlease-file-name\fR
+statement, this statement must appear in the outer scope of the configuration
+file. The order of precedence used by the server is:
+.PP
+    1. \fBpid-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD_PID\fR environment variable.
+.RE
 .PP
 The
 .I dhcpv6-pid-file-name
@@ -2646,18 +2642,12 @@ statement
 .I Name
 is the name of the pid file to use if and only if the server is running
 in DHCPv6 mode.  By default, this is DBDIR/dhcpd6.pid.  This statement,
-like
-.I pid-file-name,
-\fBmust\fR appear in the outer scope of the configuration file.  It
-has no effect if overridden by the
-.B -pf
-flag or the
-.B PATH_DHCPD6_PID
-environment variable.  If
-.I dhcpv6-pid-file-name
-is not specified, but
-.I pid-file-name
-is, the latter value will be used.
+like \fIpid-file-name\fr, \fBmust\fR appear in the outer scope of the
+configuration file.  The order of precedence used by the server is:
+.PP
+    1. \fBdhcpv6-pid-file-name\fR configuration file statement.
+    2. \fB-lf\fR command line flag.
+    3. \fBPATH_DHCPD6_PID\fR environment variable.
 .RE
 .PP
 The