Brian Murrel's latest dns update implementation - more programmability.

common/conflex.c

@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: conflex.c,v 1.49 1999/07/16 21:33:58 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: conflex.c,v 1.50 1999/07/19 01:15:10 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -414,6 +414,8 @@ static enum dhcp_token intern (atom, dfv)
 			return DDNS_FWD_NAME;
 		if (!strcasecmp (atom + 1, "dns-rev-name"))
 			return DDNS_REV_NAME;
+		if (!strcasecmp (atom + 1, "ns-update"))
+			return DNS_UPDATE;
 		if (!strcasecmp (atom + 1, "omain"))
 			return DOMAIN;
 		if (!strcasecmp (atom + 1, "eny"))
@@ -513,6 +515,8 @@ static enum dhcp_token intern (atom, dfv)
 			return LEASE;
 		if (!strcasecmp (atom + 1, "eased-address"))
 			return LEASED_ADDRESS;
+		if (!strcasecmp (atom + 1, "lease-time"))
+			return LEASE_TIME;
 		if (!strcasecmp (atom + 1, "imit"))
 			return LIMIT;
 		break;

common/nsupdate.c

@@ -25,7 +25,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: nsupdate.c,v 1.5 1999/07/18 19:37:23 mellon Exp $ Copyright (c) 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: nsupdate.c,v 1.6 1999/07/19 01:15:11 mellon Exp $ Copyright (c) 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -38,7 +38,8 @@ static char copyright[] =
    necessary which can be any combination and number of remove A, add A,
    remove PTR, add PTR */
 
-/* Return the forward name of a lease. */
+#if 0
+/* Return the reverse name of a lease. */
 char *ddns_rev_name(lease, state, packet)
 	struct lease *lease;
 	struct lease_state *state;
@@ -176,8 +177,9 @@ char *ddns_fwd_name(lease, state, packet)
 #endif
 	return hostname;
 }
+#endif
 
-int nsupdateA(hostname, ip_addr, ttl, opcode)
+static int nsupdateA(hostname, ip_addr, ttl, opcode)
 	char *hostname;
 	char *ip_addr;
 	u_int32_t ttl;
@@ -237,7 +239,7 @@ int nsupdateA(hostname, ip_addr, ttl, opcode)
 	return z;
 }
 
-int nsupdatePTR(hostname, revname, ttl, opcode)
+static int nsupdatePTR(revname, hostname, ttl, opcode)
 	char *hostname;
 	char *revname;
 	u_int32_t ttl;
@@ -262,6 +264,7 @@ int nsupdatePTR(hostname, revname, ttl, opcode)
 	return z;
 }
 
+#if 0
 void nsupdate(lease, state, packet, opcode)
 	struct lease *lease;
 	struct lease_state *state;
@@ -271,6 +274,7 @@ void nsupdate(lease, state, packet, opcode)
 	char	*hostname, *revname;
 	u_int32_t	ttl = 0;
 
+return;
 	if (!(opcode == ADD || opcode == DELETE))
 		return;
 
@@ -325,7 +329,7 @@ void nsupdate(lease, state, packet, opcode)
 			if (lease -> ddns_rev_name &&
 			    (strcmp(hostname, lease -> ddns_fwd_name) ||
 			     strcmp(revname, lease -> ddns_rev_name)) &&
-			    nsupdatePTR(lease -> ddns_fwd_name, revname,
+			    nsupdatePTR(revname, lease -> ddns_fwd_name,
 					      ttl, DELETE)) {
 				/* clear the forward DNS name pointer */
 				if (lease -> ddns_rev_name)
@@ -366,7 +370,7 @@ void nsupdate(lease, state, packet, opcode)
 
 		if (!lease -> ddns_rev_name) {
 			/* add a PTR RR */
-			if (nsupdatePTR(hostname, revname, ttl, ADD)) {
+			if (nsupdatePTR(revname, hostname, ttl, ADD)) {
 				/* remember in the lease struct for a release */
 				lease -> ddns_rev_name =
 				       dmalloc(strlen(revname) + 1, "nsupdate");
@@ -382,8 +386,9 @@ void nsupdate(lease, state, packet, opcode)
 				      piaddr(lease->ip_addr), ttl, DELETE);
 
 			if (lease -> ddns_rev_name &&
-			    nsupdatePTR(lease -> ddns_fwd_name,
+			    nsupdatePTR(lease -> ddns_rev_name,
-					lease -> ddns_rev_name, ttl, opcode)) {
+					lease -> ddns_fwd_name,
+					ttl, opcode)) {
 				/* clear the reverse DNS name pointer */
 				if (lease -> ddns_rev_name)
 					dfree(lease -> ddns_rev_name,
@@ -404,4 +409,95 @@ void nsupdate(lease, state, packet, opcode)
 	
 	return;
 }
+#endif
+
+/* public function to update an A record if needed */
+int updateA(struct data_string *lhs, struct data_string *rhs, unsigned int ttl,
+	struct lease *lease)
+{
+
+	static char hostname[MAXDNAME];
+	static char ipaddr[MAXDNAME];
+
+	hostname[0] = '\0';
+	strncat(hostname, lhs->data, lhs->len);
+	hostname[lhs->len] = '\0';
+	
+	ipaddr[0] = '\0';
+	strncat(ipaddr, rhs->data, rhs->len);
+	ipaddr[rhs->len] = '\0';
+	
+	/* delete an existing A if the one to be added is different */
+	if (lease -> ddns_fwd_name &&
+	    strcmp(hostname, lease -> ddns_fwd_name)) {
+		int y;
+		y=nsupdateA(lease -> ddns_fwd_name, ipaddr, 0, DELETE);
+
+		if (y) {
+			/* clear the forward DNS name pointer */
+			if (lease -> ddns_fwd_name)
+				dfree(lease -> ddns_fwd_name, "nsupdate");
+			lease -> ddns_fwd_name = 0;
+		}
+	}
+	/* only update if there is no A record there already */
+	if (!lease -> ddns_fwd_name) {
+		int y;
+	    	y=nsupdateA(hostname, ipaddr, ttl, ADD);
+		if (y < 1)
+			return 0;
+
+		/* remember this in the lease structure for release */
+		lease -> ddns_fwd_name = dmalloc(strlen(hostname) + 1,
+					 	 "nsupdate");
+		strcpy (lease -> ddns_fwd_name, hostname);
+	}
+
+	return 1;
+}
+
+/* public function to update an A record if needed */
+int updatePTR(struct data_string *lhs, struct data_string *rhs,
+	      unsigned int ttl, struct lease *lease)
+{
+
+	static char hostname[MAXDNAME];
+	static char revname[MAXDNAME];
+
+	revname[0] = '\0';
+	strncat(revname, lhs->data, lhs->len);
+	revname[lhs->len] = '\0';
+
+	hostname[0] = '\0';
+	strncat(hostname, rhs->data, rhs->len);
+	hostname[rhs->len] = '\0';
+	
+	/* delete an existing PTR if the one to be added is different */
+	if (lease -> ddns_rev_name &&
+	    strcmp(revname, lease -> ddns_rev_name)) {
+		int y;
+		y=nsupdatePTR(revname, hostname, 0, DELETE);
+
+		if (y) {
+			/* clear the reverse DNS name pointer */
+			if (lease -> ddns_rev_name)
+				dfree(lease -> ddns_rev_name, "nsupdate");
+			lease -> ddns_rev_name = 0;
+		}
+	}
+	/* only update if there is no PTR record there already */
+	if (!lease -> ddns_rev_name) {
+		int y;
+	    	y=nsupdatePTR(revname, hostname, ttl, ADD);
+		if (y < 1)
+			return 0;
+
+		/* remember this in the lease structure for release */
+		lease -> ddns_rev_name = dmalloc(strlen(revname) + 1,
+					 	 "nsupdate");
+		strcpy (lease -> ddns_rev_name, revname);
+	}
+
+	return 1;
+}
 #endif /* defined (NSUPDATE) */

common/parse.c

@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: parse.c,v 1.29 1999/07/16 21:33:59 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: parse.c,v 1.30 1999/07/19 01:15:11 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -1883,6 +1883,67 @@ int parse_non_binary (expr, cfile, lose, context)
 			goto norparen;
 		break;
 
+	      case DNS_UPDATE:
+#if !defined (NSUPDATE)
+		parse_warn ("you are using dns-update() but have not compiled with the NSUPDATE switch.");
+		skip_to_semi (cfile);
+		*lose = 1;
+		return 0;
+#endif
+		token = next_token (&val, cfile);
+		if (!expression_allocate (expr, "parse_expression: DNS_UPDATE"))
+			log_fatal ("can't allocate expression");
+		(*expr) -> op = expr_dns_update;
+
+		token = next_token (&val, cfile);
+		if (token != LPAREN)
+			goto nolparen;
+
+		if (!(parse_data_expression
+		      (&(*expr) -> data.dns_update.type, cfile, lose))) {
+			expression_dereference (expr,
+						"parse_expression: noRRtype");
+			parse_warn ("expecting DNS RR type.");
+			skip_to_semi (cfile);
+			*lose = 1;
+			return 0;
+		}
+
+		token = next_token (&val, cfile);
+		if (token != COMMA)
+			goto nocomma;
+
+		if (!(parse_data_expression
+		      (&(*expr) -> data.dns_update.expr1, cfile, lose)))
+			goto nodata;
+
+		token = next_token (&val, cfile);
+		if (token != COMMA)
+			goto nocomma;
+
+		if (!(parse_data_expression
+		      (&(*expr) -> data.dns_update.expr2, cfile, lose)))
+			goto nodata;
+
+		token = next_token (&val, cfile);
+		if (token != COMMA)
+			goto nocomma;
+
+		if (!(parse_data_expression
+		      (&(*expr) -> data.dns_update.ttl, cfile, lose))) {
+			expression_dereference (expr,
+						"parse_expression: nottl");
+			parse_warn ("expecting data expression.");
+			skip_to_semi (cfile);
+			*lose = 1;
+			return 0;
+		}
+
+		token = next_token (&val, cfile);
+		if (token != RPAREN)
+			goto norparen;
+		break;
+
 	      case OPTION:
 	      case CONFIG_OPTION:
 		if (!expression_allocate (expr, "parse_expression: OPTION"))
@@ -1915,6 +1976,14 @@ int parse_non_binary (expr, cfile, lose, context)
 		(*expr) -> op = expr_leased_address;
 		break;
 
+	      case LEASE_TIME:
+		token = next_token (&val, cfile);
+		if (!expression_allocate (expr,
+					"parse_expression: LEASED_LEASE_TIME"))
+			log_fatal ("can't allocate expression");
+		(*expr) -> op = expr_lease_time;
+		break;
+
 	      case HOST_DECL_NAME:
 		token = next_token (&val, cfile);
 		if (!expression_allocate (expr,

common/tree.c

@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: tree.c,v 1.33 1999/07/16 21:33:59 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: tree.c,v 1.34 1999/07/19 01:15:11 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -386,6 +386,8 @@ int evaluate_boolean_expression (result, packet, options, lease, expr)
 	struct expression *expr;
 {
 	struct data_string left, right;
+	struct data_string rrtype, expr1, expr2, ttl;
+	int s0, s1, s2, s3;
 	int bleft, bright;
 	int sleft, sright;
 
@@ -524,6 +526,48 @@ int evaluate_boolean_expression (result, packet, options, lease, expr)
 		*result = packet -> known;
 		return 1;
 
+	      case expr_dns_update:
+#if defined (NSUPDATE)
+		/* we only want to do this on a DHCPREQUEST */
+		if (packet -> packet_type != DHCPREQUEST)
+			return 0;
+		memset (&rrtype, 0, sizeof expr1);
+		s0 = evaluate_data_expression (&rrtype, packet, options, lease,
+					       expr -> data.dns_update.type);
+		memset (&expr1, 0, sizeof expr1);
+		s1 = evaluate_data_expression (&expr1, packet, options, lease,
+					       expr -> data.dns_update.expr1);
+		memset (&expr2, 0, sizeof expr2);
+		s2 = evaluate_data_expression (&expr2, packet, options, lease,
+					       expr -> data.dns_update.expr2);
+		memset (&ttl, 0, sizeof ttl);
+		s3 = evaluate_data_expression (&ttl, packet, options, lease,
+					          expr -> data.dns_update.ttl);
+
+		*result = 0;	/* assume failure */
+		if (s0 && s1 && s2 && s3) {
+			if (rrtype.len == 1 &&
+			    strncmp(rrtype.data, "a", 1) == 0) {
+log_info("calling updateA(expr1, expr2, %d, lease)", atol(ttl.data));
+				updateA(expr1, expr2, atol(ttl.data), lease);
+			} else if (rrtype.len == 3 &&
+				   strncmp(rrtype.data, "ptr", 3) == 0) {
+log_info("calling updatePTR(expr1, expr2, %d, lease)", atol(ttl.data));
+				updatePTR(expr1, expr2, atol(ttl.data), lease);
+			}
+			*result = 1;
+		}
+#if defined (DEBUG_EXPRESSIONS)
+		log_info ("dns-update(%s, %s, %s):", 
+			  print_hex_1(rrtype.len, rrtype.data, 60),
+			  print_hex_2(expr1.len, expr1.data, 60),
+			  print_hex_3(expr2.len, expr2.data, 60));
+#endif
+		return 1;
+#else
+		return 0;
+#endif
+
 	      case expr_substring:
 	      case expr_suffix:
 	      case expr_option:
@@ -542,6 +586,7 @@ int evaluate_boolean_expression (result, packet, options, lease, expr)
 	      case expr_host_decl_name:
 	      case expr_config_option:
 	      case expr_leased_address:
+	      case expr_lease_time:
 		log_error ("Data opcode in evaluate_boolean_expression: %d",
 		      expr -> op);
 		return 0;
@@ -568,7 +613,7 @@ int evaluate_data_expression (result, packet, options, lease, expr)
 	struct expression *expr;
 {
 	struct data_string data, other;
-	unsigned long offset, len;
+	unsigned long offset, len, i;
 	int s0, s1, s2, s3;
 	int status;
 
@@ -1150,6 +1195,31 @@ int evaluate_data_expression (result, packet, options, lease, expr)
 #endif
 		return 1;
 
+	      case expr_lease_time:
+		if (!lease) {
+			log_error ("data: leased_lease_time: not available");
+			return 0;
+		}
+		i = lease -> ends - lease -> starts;
+		if (buffer_allocate (&result -> buffer, 11, "lease-time")) {
+			result -> data = &result -> buffer -> data [0];
+#if defined (NO_SNPRINTF)
+			snprintf(result -> data, 11, "%lu", i);
+#else
+			snprintf(result -> data, 11, "%lu", i);
+#endif
+			result -> len = strlen(result -> data);
+			result -> terminated = 0;
+		} else {
+			log_error ("data: leased-lease-time: no memory.");
+			return 0;
+		}
+#if defined (DEBUG_EXPRESSIONS)
+		log_info ("data: leased-lease-time = %s",
+		      print_hex_1 (result -> len, result -> data, 60));
+#endif
+ 		return 1;
+ 
 	      case expr_check:
 	      case expr_equal:
 	      case expr_and:
@@ -1271,6 +1341,7 @@ int evaluate_numeric_expression (result, packet, options, lease, expr)
 	      case expr_const_int:
 		*result = expr -> data.const_int;
 		return 1;
+
 	}
 
 	log_error ("evaluate_numeric_expression: bogus opcode %d", expr -> op);
@@ -1484,6 +1555,7 @@ void expression_dereference (eptr, name)
 
 		/* No subexpressions. */
 	      case expr_leased_address:
+	      case expr_lease_time:
 	      case expr_const_int:
 	      case expr_check:
 	      case expr_option:
@@ -1547,6 +1619,7 @@ int is_boolean_expression (expr)
 		expr -> op == expr_equal ||
 		expr -> op == expr_and ||
 		expr -> op == expr_or ||
+		expr -> op == expr_dns_update ||
 		expr -> op == expr_not);
 }
 
@@ -1567,7 +1640,8 @@ int is_data_expression (expr)
 		expr -> op == expr_host_lookup ||
 		expr -> op == expr_binary_to_ascii ||
 		expr -> op == expr_reverse ||
-		expr -> op == expr_leased_address);
+		expr -> op == expr_leased_address ||
+		expr -> op == expr_lease_time);
 }
 
 int is_numeric_expression (expr)

includes/dhcpd.h

@@ -996,7 +996,7 @@ struct lease *find_lease PROTO ((struct packet *,
 struct lease *mockup_lease PROTO ((struct packet *,
 				   struct shared_network *,
 				   struct host_decl *));
-void static_lease_dereference PROTO ((struct lease *));
+void static_lease_dereference PROTO ((struct lease *, char *));
 
 struct lease *allocate_lease PROTO ((struct packet *, struct pool *, int));
 int permitted PROTO ((struct packet *, struct permit *));

includes/dhctoken.h

@@ -191,6 +191,8 @@ enum dhcp_token {
 	EXPIRY = 409,
 	RELEASE = 410,
 	COMMIT = 411,
+	DNS_UPDATE = 412,
+	LEASE_TIME = 413,
 };
 
 #define is_identifier(x)	((x) >= FIRST_TOKEN &&	\

includes/tree.h

@@ -89,6 +89,8 @@ enum expr_op {
 	expr_config_option,
 	expr_host_decl_name,
 	expr_pick_first_value,
+ 	expr_lease_time,
+ 	expr_dns_update,
 };
 
 struct expression {
@@ -137,6 +139,12 @@ struct expression {
 			struct expression *car;
 			struct expression *cdr;
 		} pick_first_value;
+ 		struct {
+ 			struct expression *type;
+ 			struct expression *expr1;
+ 			struct expression *expr2;
+ 			struct expression *ttl;
+ 		} dns_update;
 	} data;
 	int flags;
 #	define EXPR_EPHEMERAL	1

server/bootp.c

@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: bootp.c,v 1.52 1999/07/18 19:38:33 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: bootp.c,v 1.53 1999/07/19 01:15:22 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -268,7 +268,7 @@ void bootp (packet)
 
 	/* Execute the commit statements, if there are any. */
 	execute_statements (packet, lease, packet -> options,
-			    state -> options, lease -> on_commit);
+			    options, lease -> on_commit);
 
 	/* We're done with the option state. */
 	option_state_dereference (&options, "bootrequest");

server/dhcp.c

@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: dhcp.c,v 1.102 1999/07/18 19:39:14 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: dhcp.c,v 1.103 1999/07/19 01:15:22 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -294,14 +294,14 @@ void dhcprelease (packet)
 
 	/* If we found a lease, release it. */
 	if (lease) {
-#if defined (NSUPDATE)
+#if defined (NSUPDATE) && 0
 		nsupdate (lease, lease -> state, packet, DELETE);
 #endif
 	/* If there are statements to execute when the lease is
 	   committed, execute them. */
 		if (lease -> on_release) {
 			execute_statements (packet, lease, packet -> options,
-					    state -> options,
+					    (struct option_state *)0, /* XXX */
 					    lease -> on_release);
 			executable_statement_dereference (&lease -> on_release,
 							  "dhcprelease");
@@ -1254,10 +1254,12 @@ void ack_lease (packet, lease, offer, when, msg)
 	   hanging off the lease. */
 	/* why not update for static leases too? */
 	/* Because static leases aren't currently recorded? */
+/* XXX
 #if defined (NSUPDATE)
  	if (!(lease -> flags & STATIC_LEASE) && offer == DHCPACK)
  		nsupdate (lease, state, packet, ADD);
 #endif
+*/
 
 	/* If there are statements to execute when the lease is
 	   committed, execute them. */