From: David Hankins <dhankins@isc.org>
Date: Fri, 5 Oct 2007 22:29:51 +0000 (+0000)
Subject: - DDNS updates state information are now stored in 'binding scopes' that
X-Git-Tag: v4_0_0b1~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7285af3087709728f9a1917dcf7449ffca5b2f5f;p=thirdparty%2Fdhcp.git

- DDNS updates state information are now stored in 'binding scopes' that
  follow the leases through their lifecycles.  This enables DDNS teardowns
  on leases that are assigned and expired inbetween a server restart (the
  state is recovered from dhcpd.leases).  Arbitrary user-specified binding
  scopes ('set var = "value";') are not yet supported.
---

diff --git a/RELNOTES b/RELNOTES
index 6ea594cf1..4c86c815c 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -84,6 +84,12 @@ suggested fixes to <dhcp-users@isc.org>.
 
 - A core dump during expired lease cleanup has been repaired.
 
+- DDNS updates state information are now stored in 'binding scopes' that
+  follow the leases through their lifecycles.  This enables DDNS teardowns
+  on leases that are assigned and expired inbetween a server restart (the
+  state is recovered from dhcpd.leases).  Arbitrary user-specified binding
+  scopes ('set var = "value";') are not yet supported.
+
 			Changes since 4.0.0a2
 
 - Fix for startup where there are no IPv4 addresses on an interface.
diff --git a/common/discover.c b/common/discover.c
index 350dc4768..8138d4243 100644
--- a/common/discover.c
+++ b/common/discover.c
@@ -289,7 +289,10 @@ int
 next_iface(struct iface_info *info, int *err, struct iface_conf_list *ifaces) {
 	struct LIFREQ *p;
 	struct LIFREQ tmp;
+#if defined(sun) || defined(__linux)
+	/* Pointer used to remove interface aliases. */
 	char *s;
+#endif
 
 	do {
 		if (ifaces->next >= ifaces->num) {
diff --git a/server/confpars.c b/server/confpars.c
index 975fe7fcc..ed8244e52 100644
--- a/server/confpars.c
+++ b/server/confpars.c
@@ -36,6 +36,9 @@
 
 static unsigned char global_host_once = 1;
 
+static int parse_binding_value(struct parse *cfile,
+				struct binding_value *value);
+
 #if defined (TRACING)
 trace_type_t *trace_readconf_type;
 trace_type_t *trace_readleases_type;
@@ -2775,9 +2778,9 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 	struct executable_statement *on;
 	int lose;
 	TIME t;
-	char *s;
 	int noequal, newbinding;
 	struct binding *binding;
+	struct binding_value *nv;
 	isc_result_t status;
 	struct option_cache *oc;
 	pair *p;
@@ -3117,7 +3120,7 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 			}
 			executable_statement_dereference (&on, MDL);
 			break;
-			
+
 		      case OPTION:
 		      case SUPERSEDE:
 			noequal = 0;
@@ -3167,6 +3170,7 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 				binding = find_binding (lease -> scope, val);
 			else
 				binding = (struct binding *)0;
+
 			if (!binding) {
 			    if (!lease -> scope)
 				if (!(binding_scope_allocate
@@ -3185,14 +3189,11 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 			    strcpy (binding -> name, val);
 			    newbinding = 1;
 			} else  {
-				if (binding -> value)
-				  binding_value_dereference (&binding -> value,
-							   MDL);
-				newbinding = 0;
+			    newbinding = 0;
 			}
 
-			if (!binding_value_allocate (&binding -> value, MDL))
-				log_fatal ("no memory for binding value.");
+			if (!binding_value_allocate(&nv, MDL))
+				log_fatal("no memory for binding value.");
 
 			if (!noequal) {
 			    token = next_token (&val, (unsigned *)0, cfile);
@@ -3203,91 +3204,28 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 			    }
 			}
 
-			token = peek_token (&val, (unsigned *)0, cfile);
-			if (token == STRING) {
-			    token = next_token (&val, &buflen, cfile);
-			    binding -> value -> type = binding_data;
-			    binding -> value -> value.data.len = buflen;
-			    if (!(buffer_allocate
-				  (&binding -> value -> value.data.buffer,
-				   buflen + 1, MDL)))
-				log_fatal ("No memory for binding.");
-			    memcpy ((char *)
-				    (binding -> value ->
-				     value.data.buffer -> data),
-				    val, buflen + 1);
-			    binding -> value -> value.data.data =
-				binding -> value -> value.data.buffer -> data;
-			    binding -> value -> value.data.terminated = 1;
-			} else if (token == NUMBER_OR_NAME) {
-			    binding -> value -> type = binding_data;
-			    s = ((char *)
-				 (parse_numeric_aggregate
-				  (cfile, (unsigned char *)0,
-				   &binding -> value -> value.data.len,
-				   ':', 16, 8)));
-			    if (!s) {
-				    binding_value_dereference
-					    (&binding -> value, MDL);
-				    lease_dereference (&lease, MDL);
-				    return 0;
-			    }
-			    if (binding -> value -> value.data.len) {
-				if (!(buffer_allocate
-				      (&binding -> value -> value.data.buffer,
-				       binding -> value -> value.data.len + 1,
-				       MDL)))
-					log_fatal ("No memory for binding.");
-				memcpy ((binding -> value ->
-					 value.data.buffer -> data), s,
-					binding -> value -> value.data.len);
-				dfree (s, MDL);
-				binding -> value -> value.data.data =
-				 binding -> value -> value.data.buffer -> data;
-			    }
-			} else if (token == PERCENT) {
-			    token = next_token (&val, (unsigned *)0, cfile);
-			    token = next_token (&val, (unsigned *)0, cfile);
-			    if (token != NUMBER) {
-				    parse_warn (cfile,
-						"expecting decimal number.");
-				    if (token != SEMI)
-					    skip_to_semi (cfile);
-				    binding_value_dereference
-					    (&binding -> value, MDL);
-				    lease_dereference (&lease, MDL);
-				    return 0;
-			    }
-			    binding -> value -> type = binding_numeric;
-			    binding -> value -> value.intval = atol (val);
-			} else if (token == NAME) {
-				token = next_token (&val,
-						    (unsigned *)0, cfile);
-				binding -> value -> type = binding_boolean;
-				if (!strcasecmp (val, "true"))
-					binding -> value -> value.boolean = 1;
-				else if (!strcasecmp (val, "false"))
-					binding -> value -> value.boolean = 0;
-				else
-					goto badbool;
-			} else {
-			      badbool:
-				parse_warn (cfile,
-					    "expecting a constant value.");
-				skip_to_semi (cfile);
-				binding_value_dereference (&binding -> value,
-							   MDL);
-				lease_dereference (&lease, MDL);
+			if (!parse_binding_value(cfile, nv)) {
+				binding_value_dereference(&nv, MDL);
+				lease_dereference(&lease, MDL);
 				return 0;
 			}
-				
+
 			if (newbinding) {
-				binding -> next = lease -> scope -> bindings;
-				lease -> scope -> bindings = binding;
+				binding_value_reference(&binding->value,
+							nv, MDL);
+				binding->next = lease->scope->bindings;
+				lease->scope->bindings = binding;
+			} else {
+				binding_value_dereference(&binding->value, MDL);
+				binding_value_reference(&binding->value,
+							nv, MDL);
 			}
-			parse_semi (cfile);
+
+			binding_value_dereference(&nv, MDL);
+			parse_semi(cfile);
 			break;
 
+			/* case NAME: */
 		      default:
 			if (!strcasecmp (val, "ddns-fwd-name")) {
 				seenbit = 4096;
@@ -3297,7 +3235,9 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 				seenbit = 8192;
 				noequal = 1;
 				goto special_set;
-			}
+			} else
+				parse_warn(cfile, "Unexpected configuration "
+						  "directive.");
 			skip_to_semi (cfile);
 			seenbit = 0;
 			lease_dereference (&lease, MDL);
@@ -3343,6 +3283,95 @@ int parse_lease_declaration (struct lease **lp, struct parse *cfile)
 	return 1;
 }
 
+/* Parse the right side of a 'binding value'.
+ *
+ * set foo = "bar"; is a string
+ * set foo = false; is a boolean
+ * set foo = %31; is a numeric value.
+ */
+static int
+parse_binding_value(struct parse *cfile, struct binding_value *value)
+{
+	struct data_string *data;
+	unsigned char *s;
+	const char *val;
+	unsigned buflen;
+	int token;
+
+	if ((cfile == NULL) || (value == NULL))
+		log_fatal("Invalid arguments at %s:%d.", MDL);
+
+	token = peek_token(&val, NULL, cfile);
+	if (token == STRING) {
+		token = next_token(&val, &buflen, cfile);
+
+		value->type = binding_data;
+		value->value.data.len = buflen;
+
+		data = &value->value.data;
+
+		if (!buffer_allocate(&data->buffer, buflen + 1, MDL))
+			log_fatal ("No memory for binding.");
+
+		memcpy(data->buffer->data, val, buflen + 1);
+
+		data->data = data->buffer->data;
+		data->terminated = 1;
+	} else if (token == NUMBER_OR_NAME) {
+		value->type = binding_data;
+
+		data = &value->value.data;
+		s = parse_numeric_aggregate(cfile, NULL, &data->len,
+					    ':', 16, 8);
+		if (s == NULL) {
+			skip_to_semi(cfile);
+			return 0;
+		}
+
+		if (data->len) {
+			if (!buffer_allocate(&data->buffer, data->len + 1,
+					     MDL))
+				log_fatal("No memory for binding.");
+
+			memcpy(data->buffer->data, s, data->len);
+			data->data = data->buffer->data;
+
+			dfree (s, MDL);
+		}
+	} else if (token == PERCENT) {
+		token = next_token(&val, NULL, cfile);
+		token = next_token(&val, NULL, cfile);
+		if (token != NUMBER) {
+			parse_warn(cfile, "expecting decimal number.");
+			if (token != SEMI)
+				skip_to_semi(cfile);
+			return 0;
+		}
+		value->type = binding_numeric;
+		value->value.intval = atol(val);
+	} else if (token == NAME) {
+		token = next_token(&val, NULL, cfile);
+		value->type = binding_boolean;
+		if (!strcasecmp(val, "true"))
+			value->value.boolean = 1;
+		else if (!strcasecmp(val, "false"))
+			value->value.boolean = 0;
+		else {
+			parse_warn(cfile, "expecting true or false");
+			if (token != SEMI)
+				skip_to_semi(cfile);
+			return 0;
+		}
+	} else {
+		parse_warn (cfile, "expecting a constant value.");
+		if (token != SEMI)
+			skip_to_semi (cfile);
+		return 0;
+	}
+
+	return 1;
+}
+
 /* address-range-declaration :== ip-address ip-address SEMI
 			       | DYNAMIC_BOOTP ip-address ip-address SEMI */
 
@@ -3758,6 +3787,10 @@ parse_ia_na_declaration(struct parse *cfile) {
 	struct iaaddr *iaaddr;
 	struct ipv6_pool *pool;
 	char addr_buf[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")];
+	isc_boolean_t newbinding;
+	struct binding_scope *scope=NULL;
+	struct binding *bnd;
+	struct binding_value *nv=NULL;
 
 	token = next_token(&val, &len, cfile);
 	if (token != STRING) {
@@ -3818,7 +3851,9 @@ parse_ia_na_declaration(struct parse *cfile) {
 			token = next_token(&val, NULL, cfile);
 			if (token == RBRACE) break;
 
-			if (token == BINDING) {
+			switch(token) {
+				/* Lease binding state. */
+			     case BINDING:
 				token = next_token(&val, NULL, cfile);
 				if (token != STATE) {
 					parse_warn(cfile, "corrupt lease file; "
@@ -3859,15 +3894,100 @@ parse_ia_na_declaration(struct parse *cfile) {
 							  "expecting "
 							  "semicolon.");
 				}
+				break;
 
-			} else if (token == ENDS) {
+				/* Lease expiration time. */
+			      case ENDS:
 				end_time = parse_date(cfile);
-			} else {
+				break;
+
+				/* Lease binding scopes. */
+			      case TOKEN_SET:
+				token = next_token(&val, NULL, cfile);
+				if ((token != NAME) &&
+				    (token != NUMBER_OR_NAME)) {
+					parse_warn(cfile, "%s is not a valid "
+							  "variable name",
+						   val);
+					skip_to_semi(cfile);
+					continue;
+				}
+
+				if (scope != NULL)
+					bnd = find_binding(scope, val);
+				else {
+					if (!binding_scope_allocate(&scope,
+								    MDL)) {
+						log_fatal("Out of memory for "
+							  "lease binding "
+							  "scope.");
+					}
+
+					bnd = NULL;
+				}
+
+				if (bnd == NULL) {
+					bnd = dmalloc(sizeof(*bnd),
+							  MDL);
+					if (bnd == NULL) {
+						log_fatal("No memory for "
+							  "lease binding.");
+					}
+
+					bnd->name = dmalloc(strlen(val) + 1,
+							    MDL);
+					if (bnd->name == NULL) {
+						log_fatal("No memory for "
+							  "binding name.");
+					}
+					strcpy(bnd->name, val);
+
+					newbinding = ISC_TRUE;
+				} else {
+					newbinding = ISC_FALSE;
+				}
+
+				if (!binding_value_allocate(&nv, MDL)) {
+					log_fatal("no memory for binding "
+						  "value.");
+				}
+
+				token = next_token(NULL, NULL, cfile);
+				if (token != EQUAL) {
+					parse_warn(cfile, "expecting '=' in "
+							  "set statement.");
+					goto binding_err;
+				}
+
+				if (!parse_binding_value(cfile, nv)) {
+				      binding_err:
+					binding_value_dereference(&nv, MDL);
+					binding_scope_dereference(&scope, MDL);
+					return;
+				}
+
+				if (newbinding) {
+					binding_value_reference(&bnd->value,
+								nv, MDL);
+					bnd->next = scope->bindings;
+					scope->bindings = bnd;
+				} else {
+					binding_value_dereference(&bnd->value,
+								  MDL);
+					binding_value_reference(&bnd->value,
+								nv, MDL);
+				}
+
+				binding_value_dereference(&nv, MDL);
+				parse_semi(cfile);
+				break;
+
+			      default:
 				parse_warn(cfile, "corrupt lease file; "
-						  "expecting binding or ends, "
+						  "expecting ia_na contents, "
 						  "got '%s'", val);
 				skip_to_semi(cfile);
-				return;
+				continue;
 			}
 		}
 
@@ -3890,6 +4010,11 @@ parse_ia_na_declaration(struct parse *cfile) {
 		iaaddr->state = state;
 		iaaddr->valid_lifetime_end_time = end_time;
 
+		if (scope != NULL) {
+			binding_scope_reference(&iaaddr->scope, scope, MDL);
+			binding_scope_dereference(&scope, MDL);
+		}
+
 		/* add to our various structures */
 		ia_na_add_iaaddr(ia_na, iaaddr, MDL);
 		pool = NULL;
diff --git a/server/db.c b/server/db.c
index 24e2269c8..3c92c5fa9 100644
--- a/server/db.c
+++ b/server/db.c
@@ -36,6 +36,9 @@
 #include <ctype.h>
 #include <errno.h>
 
+static isc_result_t write_binding_scope(FILE *db_file, struct binding *bnd,
+					char *prepend);
+
 FILE *db_file;
 
 static int counting = 0;
@@ -43,6 +46,58 @@ static int count = 0;
 TIME write_time;
 int lease_file_is_corrupt = 0;
 
+/* Write a single binding scope value in parsable format.
+ */
+
+static isc_result_t
+write_binding_scope(FILE *db_file, struct binding *bnd, char *prepend) {
+	char *s;
+
+	if ((db_file == NULL) || (bnd == NULL) || (prepend == NULL))
+		return ISC_R_INVALIDARG;
+
+	if (bnd->value->type == binding_data) {
+		if (bnd->value->value.data.data != NULL) {
+			s = quotify_buf(bnd->value->value.data.data,
+					bnd->value->value.data.len, MDL);
+			if (s != NULL) {
+				errno = 0;
+				fprintf(db_file, "%sset %s = \"%s\";",
+					prepend, bnd->name, s);
+				if (errno)
+					return ISC_R_FAILURE;
+
+				dfree(s, MDL);
+			} else {
+			    return ISC_R_FAILURE;
+			}
+		}
+	} else if (bnd->value->type == binding_numeric) {
+		errno = 0;
+		fprintf(db_file, "%sset %s = %%%ld;", prepend,
+			bnd->name, bnd->value->value.intval);
+		if (errno)
+			return ISC_R_FAILURE;
+	} else if (bnd->value->type == binding_boolean) {
+		errno = 0;
+		fprintf(db_file, "%sset %s = %s;", prepend, bnd->name,
+			bnd->value->value.intval ? "true" : "false");
+		if (errno)
+			return ISC_R_FAILURE;
+	} else if (bnd->value->type == binding_dns) {
+		log_error("%s: persistent dns values not supported.",
+			  bnd->name);
+	} else if (bnd->value->type == binding_function) {
+		log_error("%s: persistent functions not supported.",
+			  bnd->name);
+	} else {
+		log_fatal("%s: unknown binding type %d", bnd->name,
+			  bnd->value->type);
+	}
+
+	return ISC_R_SUCCESS;
+}
+
 /* Write the specified lease to the current lease database file. */
 
 int write_lease (lease)
@@ -152,49 +207,17 @@ int write_lease (lease)
 		} else
 			++errors;
 	}
-	if (lease -> scope) {
-	    for (b = lease -> scope -> bindings; b; b = b -> next) {
-		if (!b -> value)
+
+	if (lease->scope != NULL) {
+	    for (b = lease->scope->bindings; b; b = b->next) {
+		if (!b->value)
 			continue;
-		if (b -> value -> type == binding_data) {
-		    if (b -> value -> value.data.data) {
-			s = quotify_buf (b -> value -> value.data.data,
-					 b -> value -> value.data.len, MDL);
-			if (s) {
-			    errno = 0;
-			    fprintf (db_file, "\n  set %s = \"%s\";",
-				     b -> name, s);
-			    if (errno)
-				++errors;
-			    dfree (s, MDL);
-			} else
-			    ++errors;
-		    }
-		} else if (b -> value -> type == binding_numeric) {
-		    errno = 0;
-		    fprintf (db_file, "\n  set %s = %%%ld;",
-			     b -> name, b -> value -> value.intval);
-		    if (errno)
+
+		if (write_binding_scope(db_file, b, "\n  ") != ISC_R_SUCCESS)
 			++errors;
-		} else if (b -> value -> type == binding_boolean) {
-		    errno = 0;
-		    fprintf (db_file, "\n  set %s = %s;",
-			     b -> name,
-			     b -> value -> value.intval ? "true" : "false");
-		    if (errno)
-			    ++errors;
-		} else if (b -> value -> type == binding_dns) {
-			log_error ("%s: persistent dns values not supported.",
-				   b -> name);
-		} else if (b -> value -> type == binding_function) {
-			log_error ("%s: persistent functions not supported.",
-				   b -> name);
-		} else {
-			log_error ("%s: unknown binding type %d",
-				   b -> name, b -> value -> type);
-		}
 	    }
 	}
+
 	if (lease -> agent_options) {
 	    struct option_cache *oc;
 	    struct data_string ds;
@@ -479,6 +502,7 @@ int write_group (group)
 int
 write_ia_na(const struct ia_na *ia_na) {
 	struct iaaddr *iaaddr;
+	struct binding *bnd;
 	int i;
 	char addr_buf[sizeof("ffff:ffff:ffff:ffff:ffff:ffff.255.255.255.255")];
 	const char *binding_state;
@@ -526,6 +550,10 @@ write_ia_na(const struct ia_na *ia_na) {
 			    binding_state) < 0) {
 			goto error_exit;
 		}
+
+		/* Note that from here on out, the \n is prepended to the
+		 * next write, rather than appended to the current write.
+		 */
 		tval = print_time(iaaddr->valid_lifetime_end_time);
 		if (tval == NULL) {
 			goto error_exit;
@@ -533,6 +561,28 @@ write_ia_na(const struct ia_na *ia_na) {
 		if (fprintf(db_file, "    ends %s", tval) < 0) {
 			goto error_exit;
 		}
+
+		/* Write out any binding scopes: note that 'ends' above does
+		 * not have \n on the end!  We want that.
+		 */
+		if (iaaddr->scope != NULL)
+			bnd = iaaddr->scope->bindings;
+		else
+			bnd = NULL;
+
+		for (; bnd != NULL ; bnd = bnd->next) {
+			if (bnd->value == NULL)
+				continue;
+
+			/* We don't do a regular error_exit because the
+			 * lease db is not corrupt in this case.
+			 */
+			if (write_binding_scope(db_file, bnd,
+						"\n    ") != ISC_R_SUCCESS)
+				goto error_exit;
+				
+		}
+
 		if (fprintf(db_file, "\n  }\n") < 0)
                         goto error_exit;
 	}
diff --git a/server/dhcpv6.c b/server/dhcpv6.c
index 13ac3e4e3..327114a38 100644
--- a/server/dhcpv6.c
+++ b/server/dhcpv6.c
@@ -1597,8 +1597,6 @@ lease_to_client(struct data_string *reply_ret,
 					       ia_na->iaid_duid.data,
 				               ia_na->iaid_duid.len, 
 					       ia_na, MDL);
-				write_ia_na(ia_na);
-				schedule_lease_timeout(lease->ipv6_pool);
 
 				/* If this constitutes a binding, and we
 				 * are performing ddns updates, then give
@@ -1622,6 +1620,9 @@ lease_to_client(struct data_string *reply_ret,
 						     lease, /* XXX */ NULL,
 						     opt_state);
 				}
+
+				write_ia_na(ia_na);
+                                schedule_lease_timeout(lease->ipv6_pool);
 			/* 
 			 * On SOLICIT, we want to forget this lease since we're
 			 * not actually doing anything with it.
diff --git a/server/mdb6.c b/server/mdb6.c
index 938abe9d9..87269ee70 100644
--- a/server/mdb6.c
+++ b/server/mdb6.c
@@ -828,6 +828,14 @@ move_lease_to_inactive(struct ipv6_pool *pool, struct iaaddr *addr,
 	old_heap_index = addr->heap_index;
 	insert_result = isc_heap_insert(pool->inactive_timeouts, addr);
 	if (insert_result == ISC_R_SUCCESS) {
+		/* Process events upon expiration. */
+		ddns_removals(NULL, addr);
+
+		/* Binding scopes are no longer valid after expiry or
+		 * release.
+		 */
+		binding_scope_dereference(&addr->scope, MDL);
+
 		iaaddr_hash_delete(pool->addrs, 
 				   &addr->addr, sizeof(addr->addr), MDL);
 		isc_heap_delete(pool->active_timeouts, old_heap_index);