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-rw-r--r--lib/lwres/getrrset.c287
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diff --git a/lib/lwres/getrrset.c b/lib/lwres/getrrset.c
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+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/* $Id: getrrset.c,v 1.18 2007/06/19 23:47:22 tbox Exp $ */
+
+/*! \file */
+
+/**
+ * DESCRIPTION
+ *
+ * lwres_getrrsetbyname() gets a set of resource records associated with
+ * a hostname, class, and type. hostname is a pointer a to
+ * null-terminated string. The flags field is currently unused and must
+ * be zero.
+ *
+ * After a successful call to lwres_getrrsetbyname(), *res is a pointer
+ * to an #rrsetinfo structure, containing a list of one or more #rdatainfo
+ * structures containing resource records and potentially another list of
+ * rdatainfo structures containing SIG resource records associated with
+ * those records. The members #rri_rdclass and #rri_rdtype are copied from
+ * the parameters. #rri_ttl and #rri_name are properties of the obtained
+ * rrset. The resource records contained in #rri_rdatas and #rri_sigs are
+ * in uncompressed DNS wire format. Properties of the rdataset are
+ * represented in the #rri_flags bitfield. If the #RRSET_VALIDATED bit is
+ * set, the data has been DNSSEC validated and the signatures verified.
+ *
+ * All of the information returned by lwres_getrrsetbyname() is
+ * dynamically allocated: the rrsetinfo and rdatainfo structures, and the
+ * canonical host name strings pointed to by the rrsetinfostructure.
+ * Memory allocated for the dynamically allocated structures created by a
+ * successful call to lwres_getrrsetbyname() is released by
+ * lwres_freerrset(). rrset is a pointer to a struct rrset created by a
+ * call to lwres_getrrsetbyname().
+ *
+ * The following structures are used:
+ *
+ * \code
+ * struct rdatainfo {
+ * unsigned int rdi_length; // length of data
+ * unsigned char *rdi_data; // record data
+ * };
+ *
+ * struct rrsetinfo {
+ * unsigned int rri_flags; // RRSET_VALIDATED...
+ * unsigned int rri_rdclass; // class number
+ * unsigned int rri_rdtype; // RR type number
+ * unsigned int rri_ttl; // time to live
+ * unsigned int rri_nrdatas; // size of rdatas array
+ * unsigned int rri_nsigs; // size of sigs array
+ * char *rri_name; // canonical name
+ * struct rdatainfo *rri_rdatas; // individual records
+ * struct rdatainfo *rri_sigs; // individual signatures
+ * };
+ * \endcode
+ *
+ * \section getrrset_return Return Values
+ *
+ * lwres_getrrsetbyname() returns zero on success, and one of the
+ * following error codes if an error occurred:
+ *
+ * \li #ERRSET_NONAME: the name does not exist
+ *
+ * \li #ERRSET_NODATA:
+ * the name exists, but does not have data of the desired type
+ *
+ * \li #ERRSET_NOMEMORY:
+ * memory could not be allocated
+ *
+ * \li #ERRSET_INVAL:
+ * a parameter is invalid
+ *
+ * \li #ERRSET_FAIL:
+ * other failure
+ */
+
+#include <config.h>
+
+#include <inttypes.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include <lwres/lwres.h>
+#include <lwres/net.h>
+#include <lwres/netdb.h> /* XXX #include <netdb.h> */
+
+#include "assert_p.h"
+
+/*!
+ * Structure to map results
+ */
+static unsigned int
+lwresult_to_result(lwres_result_t lwresult) {
+ switch (lwresult) {
+ case LWRES_R_SUCCESS: return (ERRSET_SUCCESS);
+ case LWRES_R_NOMEMORY: return (ERRSET_NOMEMORY);
+ case LWRES_R_NOTFOUND: return (ERRSET_NONAME);
+ case LWRES_R_TYPENOTFOUND: return (ERRSET_NODATA);
+ default: return (ERRSET_FAIL);
+ }
+}
+
+/*@{*/
+/*!
+ * malloc / calloc functions that guarantee to only
+ * return NULL if there is an error, like they used
+ * to before the ANSI C committee broke them.
+ */
+
+static void *
+sane_malloc(size_t size) {
+ if (size == 0U)
+ size = 1;
+ return (malloc(size));
+}
+
+static void *
+sane_calloc(size_t number, size_t size) {
+ size_t len = number * size;
+ void *mem = sane_malloc(len);
+ if (mem != NULL)
+ memset(mem, 0, len);
+ return (mem);
+}
+/*@}*/
+
+/*% Returns a set of resource records associated with a hostname, class, and type. hostname is a pointer a to null-terminated string. */
+int
+lwres_getrrsetbyname(const char *hostname, unsigned int rdclass,
+ unsigned int rdtype, unsigned int flags,
+ struct rrsetinfo **res)
+{
+ lwres_context_t *lwrctx = NULL;
+ lwres_result_t lwresult;
+ lwres_grbnresponse_t *response = NULL;
+ struct rrsetinfo *rrset = NULL;
+ unsigned int i;
+ unsigned int lwflags;
+ unsigned int result;
+
+ if (rdclass > 0xffff || rdtype > 0xffff) {
+ result = ERRSET_INVAL;
+ goto fail;
+ }
+
+ /*
+ * Don't allow queries of class or type ANY
+ */
+ if (rdclass == 0xff || rdtype == 0xff) {
+ result = ERRSET_INVAL;
+ goto fail;
+ }
+
+ lwresult = lwres_context_create(&lwrctx, NULL, NULL, NULL, 0);
+ if (lwresult != LWRES_R_SUCCESS) {
+ result = lwresult_to_result(lwresult);
+ goto fail;
+ }
+ (void) lwres_conf_parse(lwrctx, lwres_resolv_conf);
+
+ /*
+ * If any input flags were defined, lwflags would be set here
+ * based on them
+ */
+ UNUSED(flags);
+ lwflags = 0;
+
+ lwresult = lwres_getrdatabyname(lwrctx, hostname,
+ (uint16_t)rdclass,
+ (uint16_t)rdtype,
+ lwflags, &response);
+ if (lwresult != LWRES_R_SUCCESS) {
+ result = lwresult_to_result(lwresult);
+ goto fail;
+ }
+
+ rrset = sane_malloc(sizeof(struct rrsetinfo));
+ if (rrset == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ rrset->rri_name = NULL;
+ rrset->rri_rdclass = response->rdclass;
+ rrset->rri_rdtype = response->rdtype;
+ rrset->rri_ttl = response->ttl;
+ rrset->rri_flags = 0;
+ rrset->rri_nrdatas = 0;
+ rrset->rri_rdatas = NULL;
+ rrset->rri_nsigs = 0;
+ rrset->rri_sigs = NULL;
+
+ rrset->rri_name = sane_malloc(response->realnamelen + 1);
+ if (rrset->rri_name == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ strncpy(rrset->rri_name, response->realname, response->realnamelen);
+ rrset->rri_name[response->realnamelen] = 0;
+
+ if ((response->flags & LWRDATA_VALIDATED) != 0)
+ rrset->rri_flags |= RRSET_VALIDATED;
+
+ rrset->rri_nrdatas = response->nrdatas;
+ rrset->rri_rdatas = sane_calloc(rrset->rri_nrdatas,
+ sizeof(struct rdatainfo));
+ if (rrset->rri_rdatas == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ for (i = 0; i < rrset->rri_nrdatas; i++) {
+ rrset->rri_rdatas[i].rdi_length = response->rdatalen[i];
+ rrset->rri_rdatas[i].rdi_data =
+ sane_malloc(rrset->rri_rdatas[i].rdi_length);
+ if (rrset->rri_rdatas[i].rdi_data == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ memmove(rrset->rri_rdatas[i].rdi_data, response->rdatas[i],
+ rrset->rri_rdatas[i].rdi_length);
+ }
+ rrset->rri_nsigs = response->nsigs;
+ rrset->rri_sigs = sane_calloc(rrset->rri_nsigs,
+ sizeof(struct rdatainfo));
+ if (rrset->rri_sigs == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ for (i = 0; i < rrset->rri_nsigs; i++) {
+ rrset->rri_sigs[i].rdi_length = response->siglen[i];
+ rrset->rri_sigs[i].rdi_data =
+ sane_malloc(rrset->rri_sigs[i].rdi_length);
+ if (rrset->rri_sigs[i].rdi_data == NULL) {
+ result = ERRSET_NOMEMORY;
+ goto fail;
+ }
+ memmove(rrset->rri_sigs[i].rdi_data, response->sigs[i],
+ rrset->rri_sigs[i].rdi_length);
+ }
+
+ lwres_grbnresponse_free(lwrctx, &response);
+ lwres_conf_clear(lwrctx);
+ lwres_context_destroy(&lwrctx);
+ *res = rrset;
+ return (ERRSET_SUCCESS);
+ fail:
+ if (rrset != NULL)
+ lwres_freerrset(rrset);
+ if (response != NULL)
+ lwres_grbnresponse_free(lwrctx, &response);
+ if (lwrctx != NULL) {
+ lwres_conf_clear(lwrctx);
+ lwres_context_destroy(&lwrctx);
+ }
+ return (result);
+}
+
+/*% Releases memory allocated for the dynamically allocated structures created by a successful call to lwres_getrrsetbyname(). */
+void
+lwres_freerrset(struct rrsetinfo *rrset) {
+ unsigned int i;
+ if (rrset->rri_rdatas != NULL) {
+ for (i = 0; i < rrset->rri_nrdatas; i++) {
+ if (rrset->rri_rdatas[i].rdi_data == NULL)
+ break;
+ free(rrset->rri_rdatas[i].rdi_data);
+ }
+ free(rrset->rri_rdatas);
+ }
+ if (rrset->rri_sigs != NULL) {
+ for (i = 0; i < rrset->rri_nsigs; i++) {
+ if (rrset->rri_sigs[i].rdi_data == NULL)
+ break;
+ free(rrset->rri_sigs[i].rdi_data);
+ }
+ free(rrset->rri_sigs);
+ }
+ free(rrset->rri_name);
+ free(rrset);
+}
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