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diff --git a/lib/lwres/lwres_gabn.c b/lib/lwres/lwres_gabn.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: lwres_gabn.c,v 1.33 2007/06/19 23:47:22 tbox Exp $ */
+
+/*! \file lwres_gabn.c
+ These are low-level routines for creating and parsing lightweight
+ resolver name-to-address lookup request and response messages.
+
+ There are four main functions for the getaddrbyname opcode. One render
+ function converts a getaddrbyname request structure --
+ lwres_gabnrequest_t -- to the lighweight resolver's canonical format.
+ It is complemented by a parse function that converts a packet in this
+ canonical format to a getaddrbyname request structure. Another render
+ function converts the getaddrbyname response structure --
+ lwres_gabnresponse_t -- to the canonical format. This is complemented
+ by a parse function which converts a packet in canonical format to a
+ getaddrbyname response structure.
+
+ These structures are defined in \link lwres.h <lwres/lwres.h>.\endlink They are shown below.
+
+\code
+#define LWRES_OPCODE_GETADDRSBYNAME 0x00010001U
+
+typedef struct lwres_addr lwres_addr_t;
+typedef LWRES_LIST(lwres_addr_t) lwres_addrlist_t;
+
+typedef struct {
+ uint32_t flags;
+ uint32_t addrtypes;
+ uint16_t namelen;
+ char *name;
+} lwres_gabnrequest_t;
+
+typedef struct {
+ uint32_t flags;
+ uint16_t naliases;
+ uint16_t naddrs;
+ char *realname;
+ char **aliases;
+ uint16_t realnamelen;
+ uint16_t *aliaslen;
+ lwres_addrlist_t addrs;
+ void *base;
+ size_t baselen;
+} lwres_gabnresponse_t;
+\endcode
+
+ lwres_gabnrequest_render() uses resolver context ctx to convert
+ getaddrbyname request structure req to canonical format. The packet
+ header structure pkt is initialised and transferred to buffer b. The
+ contents of *req are then appended to the buffer in canonical format.
+ lwres_gabnresponse_render() performs the same task, except it converts
+ a getaddrbyname response structure lwres_gabnresponse_t to the
+ lightweight resolver's canonical format.
+
+ lwres_gabnrequest_parse() uses context ctx to convert the contents of
+ packet pkt to a lwres_gabnrequest_t structure. Buffer b provides space
+ to be used for storing this structure. When the function succeeds, the
+ resulting lwres_gabnrequest_t is made available through *structp.
+ lwres_gabnresponse_parse() offers the same semantics as
+ lwres_gabnrequest_parse() except it yields a lwres_gabnresponse_t
+ structure.
+
+ lwres_gabnresponse_free() and lwres_gabnrequest_free() release the
+ memory in resolver context ctx that was allocated to the
+ lwres_gabnresponse_t or lwres_gabnrequest_t structures referenced via
+ structp. Any memory associated with ancillary buffers and strings for
+ those structures is also discarded.
+
+\section lwres_gabn_return Return Values
+
+ The getaddrbyname opcode functions lwres_gabnrequest_render(),
+ lwres_gabnresponse_render() lwres_gabnrequest_parse() and
+ lwres_gabnresponse_parse() all return #LWRES_R_SUCCESS on success. They
+ return #LWRES_R_NOMEMORY if memory allocation fails.
+ #LWRES_R_UNEXPECTEDEND is returned if the available space in the buffer
+ b is too small to accommodate the packet header or the
+ lwres_gabnrequest_t and lwres_gabnresponse_t structures.
+ lwres_gabnrequest_parse() and lwres_gabnresponse_parse() will return
+ #LWRES_R_UNEXPECTEDEND if the buffer is not empty after decoding the
+ received packet. These functions will return #LWRES_R_FAILURE if
+ pktflags in the packet header structure #lwres_lwpacket_t indicate that
+ the packet is not a response to an earlier query.
+
+\section lwres_gabn_see See Also
+
+ \link lwpacket.c lwres_lwpacket \endlink
+ */
+
+#include <config.h>
+
+#include <assert.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <lwres/lwbuffer.h>
+#include <lwres/lwpacket.h>
+#include <lwres/lwres.h>
+#include <lwres/result.h>
+
+#include "context_p.h"
+#include "assert_p.h"
+
+/*% uses resolver context ctx to convert getaddrbyname request structure req to canonical format. */
+lwres_result_t
+lwres_gabnrequest_render(lwres_context_t *ctx, lwres_gabnrequest_t *req,
+ lwres_lwpacket_t *pkt, lwres_buffer_t *b)
+{
+ unsigned char *buf;
+ size_t buflen;
+ int ret;
+ size_t payload_length;
+ uint16_t datalen;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(req != NULL);
+ REQUIRE(req->name != NULL);
+ REQUIRE(pkt != NULL);
+ REQUIRE(b != NULL);
+
+ datalen = (uint16_t) strlen(req->name);
+
+ payload_length = 4 + 4 + 2 + req->namelen + 1;
+
+ buflen = LWRES_LWPACKET_LENGTH + payload_length;
+ buf = CTXMALLOC(buflen);
+ if (buf == NULL)
+ return (LWRES_R_NOMEMORY);
+
+ lwres_buffer_init(b, buf, (unsigned int)buflen);
+
+ pkt->length = (uint32_t)buflen;
+ pkt->version = LWRES_LWPACKETVERSION_0;
+ pkt->pktflags &= ~LWRES_LWPACKETFLAG_RESPONSE;
+ pkt->opcode = LWRES_OPCODE_GETADDRSBYNAME;
+ pkt->result = 0;
+ pkt->authtype = 0;
+ pkt->authlength = 0;
+
+ ret = lwres_lwpacket_renderheader(b, pkt);
+ if (ret != LWRES_R_SUCCESS) {
+ lwres_buffer_invalidate(b);
+ CTXFREE(buf, buflen);
+ return (ret);
+ }
+
+ INSIST(SPACE_OK(b, payload_length));
+
+ /*
+ * Flags.
+ */
+ lwres_buffer_putuint32(b, req->flags);
+
+ /*
+ * Address types we'll accept.
+ */
+ lwres_buffer_putuint32(b, req->addrtypes);
+
+ /*
+ * Put the length and the data. We know this will fit because we
+ * just checked for it.
+ */
+ lwres_buffer_putuint16(b, datalen);
+ lwres_buffer_putmem(b, (unsigned char *)req->name, datalen);
+ lwres_buffer_putuint8(b, 0); /* trailing NUL */
+
+ INSIST(LWRES_BUFFER_AVAILABLECOUNT(b) == 0);
+
+ return (LWRES_R_SUCCESS);
+}
+/*% converts a getaddrbyname response structure lwres_gabnresponse_t to the lightweight resolver's canonical format. */
+lwres_result_t
+lwres_gabnresponse_render(lwres_context_t *ctx, lwres_gabnresponse_t *req,
+ lwres_lwpacket_t *pkt, lwres_buffer_t *b)
+{
+ unsigned char *buf;
+ size_t buflen;
+ int ret;
+ size_t payload_length;
+ uint16_t datalen;
+ lwres_addr_t *addr;
+ int x;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(req != NULL);
+ REQUIRE(pkt != NULL);
+ REQUIRE(b != NULL);
+
+ /* naliases, naddrs */
+ payload_length = 4 + 2 + 2;
+ /* real name encoding */
+ payload_length += 2 + req->realnamelen + 1;
+ /* each alias */
+ for (x = 0; x < req->naliases; x++)
+ payload_length += 2 + req->aliaslen[x] + 1;
+ /* each address */
+ x = 0;
+ addr = LWRES_LIST_HEAD(req->addrs);
+ while (addr != NULL) {
+ payload_length += 4 + 2;
+ payload_length += addr->length;
+ addr = LWRES_LIST_NEXT(addr, link);
+ x++;
+ }
+ INSIST(x == req->naddrs);
+
+ buflen = LWRES_LWPACKET_LENGTH + payload_length;
+ buf = CTXMALLOC(buflen);
+ if (buf == NULL)
+ return (LWRES_R_NOMEMORY);
+ lwres_buffer_init(b, buf, (unsigned int)buflen);
+
+ pkt->length = (uint32_t)buflen;
+ pkt->version = LWRES_LWPACKETVERSION_0;
+ pkt->pktflags |= LWRES_LWPACKETFLAG_RESPONSE;
+ pkt->opcode = LWRES_OPCODE_GETADDRSBYNAME;
+ pkt->authtype = 0;
+ pkt->authlength = 0;
+
+ ret = lwres_lwpacket_renderheader(b, pkt);
+ if (ret != LWRES_R_SUCCESS) {
+ lwres_buffer_invalidate(b);
+ CTXFREE(buf, buflen);
+ return (ret);
+ }
+
+ /*
+ * Check space needed here.
+ */
+ INSIST(SPACE_OK(b, payload_length));
+
+ /* Flags. */
+ lwres_buffer_putuint32(b, req->flags);
+
+ /* encode naliases and naddrs */
+ lwres_buffer_putuint16(b, req->naliases);
+ lwres_buffer_putuint16(b, req->naddrs);
+
+ /* encode the real name */
+ datalen = req->realnamelen;
+ lwres_buffer_putuint16(b, datalen);
+ lwres_buffer_putmem(b, (unsigned char *)req->realname, datalen);
+ lwres_buffer_putuint8(b, 0);
+
+ /* encode the aliases */
+ for (x = 0; x < req->naliases; x++) {
+ datalen = req->aliaslen[x];
+ lwres_buffer_putuint16(b, datalen);
+ lwres_buffer_putmem(b, (unsigned char *)req->aliases[x],
+ datalen);
+ lwres_buffer_putuint8(b, 0);
+ }
+
+ /* encode the addresses */
+ addr = LWRES_LIST_HEAD(req->addrs);
+ while (addr != NULL) {
+ lwres_buffer_putuint32(b, addr->family);
+ lwres_buffer_putuint16(b, addr->length);
+ lwres_buffer_putmem(b, addr->address, addr->length);
+ addr = LWRES_LIST_NEXT(addr, link);
+ }
+
+ INSIST(LWRES_BUFFER_AVAILABLECOUNT(b) == 0);
+ INSIST(LWRES_BUFFER_USEDCOUNT(b) == pkt->length);
+
+ return (LWRES_R_SUCCESS);
+}
+/*% Uses context ctx to convert the contents of packet pkt to a lwres_gabnrequest_t structure. */
+lwres_result_t
+lwres_gabnrequest_parse(lwres_context_t *ctx, lwres_buffer_t *b,
+ lwres_lwpacket_t *pkt, lwres_gabnrequest_t **structp)
+{
+ int ret;
+ char *name;
+ lwres_gabnrequest_t *gabn;
+ uint32_t addrtypes;
+ uint32_t flags;
+ uint16_t namelen;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(pkt != NULL);
+ REQUIRE(b != NULL);
+ REQUIRE(structp != NULL && *structp == NULL);
+
+ if ((pkt->pktflags & LWRES_LWPACKETFLAG_RESPONSE) != 0)
+ return (LWRES_R_FAILURE);
+
+ if (!SPACE_REMAINING(b, 4 + 4))
+ return (LWRES_R_UNEXPECTEDEND);
+
+ flags = lwres_buffer_getuint32(b);
+ addrtypes = lwres_buffer_getuint32(b);
+
+ /*
+ * Pull off the name itself
+ */
+ ret = lwres_string_parse(b, &name, &namelen);
+ if (ret != LWRES_R_SUCCESS)
+ return (ret);
+
+ if (LWRES_BUFFER_REMAINING(b) != 0)
+ return (LWRES_R_TRAILINGDATA);
+
+ gabn = CTXMALLOC(sizeof(lwres_gabnrequest_t));
+ if (gabn == NULL)
+ return (LWRES_R_NOMEMORY);
+
+ gabn->flags = flags;
+ gabn->addrtypes = addrtypes;
+ gabn->name = name;
+ gabn->namelen = namelen;
+
+ *structp = gabn;
+ return (LWRES_R_SUCCESS);
+}
+
+/*% Offers the same semantics as lwres_gabnrequest_parse() except it yields a lwres_gabnresponse_t structure. */
+
+lwres_result_t
+lwres_gabnresponse_parse(lwres_context_t *ctx, lwres_buffer_t *b,
+ lwres_lwpacket_t *pkt, lwres_gabnresponse_t **structp)
+{
+ lwres_result_t ret;
+ unsigned int x;
+ uint32_t flags;
+ uint16_t naliases;
+ uint16_t naddrs;
+ lwres_gabnresponse_t *gabn;
+ lwres_addrlist_t addrlist;
+ lwres_addr_t *addr;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(pkt != NULL);
+ REQUIRE(b != NULL);
+ REQUIRE(structp != NULL && *structp == NULL);
+
+ gabn = NULL;
+
+ if ((pkt->pktflags & LWRES_LWPACKETFLAG_RESPONSE) == 0)
+ return (LWRES_R_FAILURE);
+
+ /*
+ * Pull off the name itself
+ */
+ if (!SPACE_REMAINING(b, 4 + 2 + 2))
+ return (LWRES_R_UNEXPECTEDEND);
+ flags = lwres_buffer_getuint32(b);
+ naliases = lwres_buffer_getuint16(b);
+ naddrs = lwres_buffer_getuint16(b);
+
+ gabn = CTXMALLOC(sizeof(lwres_gabnresponse_t));
+ if (gabn == NULL)
+ return (LWRES_R_NOMEMORY);
+ gabn->aliases = NULL;
+ gabn->aliaslen = NULL;
+ LWRES_LIST_INIT(gabn->addrs);
+ gabn->base = NULL;
+
+ gabn->flags = flags;
+ gabn->naliases = naliases;
+ gabn->naddrs = naddrs;
+
+ LWRES_LIST_INIT(addrlist);
+
+ if (naliases > 0) {
+ gabn->aliases = CTXMALLOC(sizeof(char *) * naliases);
+ if (gabn->aliases == NULL) {
+ ret = LWRES_R_NOMEMORY;
+ goto out;
+ }
+
+ gabn->aliaslen = CTXMALLOC(sizeof(uint16_t) * naliases);
+ if (gabn->aliaslen == NULL) {
+ ret = LWRES_R_NOMEMORY;
+ goto out;
+ }
+ }
+
+ for (x = 0; x < naddrs; x++) {
+ addr = CTXMALLOC(sizeof(lwres_addr_t));
+ if (addr == NULL) {
+ ret = LWRES_R_NOMEMORY;
+ goto out;
+ }
+ LWRES_LINK_INIT(addr, link);
+ LWRES_LIST_APPEND(addrlist, addr, link);
+ }
+
+ /*
+ * Now, pull off the real name.
+ */
+ ret = lwres_string_parse(b, &gabn->realname, &gabn->realnamelen);
+ if (ret != LWRES_R_SUCCESS)
+ goto out;
+
+ /*
+ * Parse off the aliases.
+ */
+ for (x = 0; x < gabn->naliases; x++) {
+ ret = lwres_string_parse(b, &gabn->aliases[x],
+ &gabn->aliaslen[x]);
+ if (ret != LWRES_R_SUCCESS)
+ goto out;
+ }
+
+ /*
+ * Pull off the addresses. We already strung the linked list
+ * up above.
+ */
+ addr = LWRES_LIST_HEAD(addrlist);
+ for (x = 0; x < gabn->naddrs; x++) {
+ INSIST(addr != NULL);
+ ret = lwres_addr_parse(b, addr);
+ if (ret != LWRES_R_SUCCESS)
+ goto out;
+ addr = LWRES_LIST_NEXT(addr, link);
+ }
+
+ if (LWRES_BUFFER_REMAINING(b) != 0) {
+ ret = LWRES_R_TRAILINGDATA;
+ goto out;
+ }
+
+ gabn->addrs = addrlist;
+
+ *structp = gabn;
+ return (LWRES_R_SUCCESS);
+
+ out:
+ if (gabn != NULL) {
+ if (gabn->aliases != NULL)
+ CTXFREE(gabn->aliases, sizeof(char *) * naliases);
+ if (gabn->aliaslen != NULL)
+ CTXFREE(gabn->aliaslen,
+ sizeof(uint16_t) * naliases);
+ addr = LWRES_LIST_HEAD(addrlist);
+ while (addr != NULL) {
+ LWRES_LIST_UNLINK(addrlist, addr, link);
+ CTXFREE(addr, sizeof(lwres_addr_t));
+ addr = LWRES_LIST_HEAD(addrlist);
+ }
+ CTXFREE(gabn, sizeof(lwres_gabnresponse_t));
+ }
+
+ return (ret);
+}
+
+/*% Release the memory in resolver context ctx that was allocated to the lwres_gabnrequest_t. */
+void
+lwres_gabnrequest_free(lwres_context_t *ctx, lwres_gabnrequest_t **structp)
+{
+ lwres_gabnrequest_t *gabn;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(structp != NULL && *structp != NULL);
+
+ gabn = *structp;
+ *structp = NULL;
+
+ CTXFREE(gabn, sizeof(lwres_gabnrequest_t));
+}
+
+/*% Release the memory in resolver context ctx that was allocated to the lwres_gabnresponse_t. */
+void
+lwres_gabnresponse_free(lwres_context_t *ctx, lwres_gabnresponse_t **structp)
+{
+ lwres_gabnresponse_t *gabn;
+ lwres_addr_t *addr;
+
+ REQUIRE(ctx != NULL);
+ REQUIRE(structp != NULL && *structp != NULL);
+
+ gabn = *structp;
+ *structp = NULL;
+
+ if (gabn->naliases > 0) {
+ CTXFREE(gabn->aliases, sizeof(char *) * gabn->naliases);
+ CTXFREE(gabn->aliaslen,
+ sizeof(uint16_t) * gabn->naliases);
+ }
+ addr = LWRES_LIST_HEAD(gabn->addrs);
+ while (addr != NULL) {
+ LWRES_LIST_UNLINK(gabn->addrs, addr, link);
+ CTXFREE(addr, sizeof(lwres_addr_t));
+ addr = LWRES_LIST_HEAD(gabn->addrs);
+ }
+ if (gabn->base != NULL)
+ CTXFREE(gabn->base, gabn->baselen);
+ CTXFREE(gabn, sizeof(lwres_gabnresponse_t));
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 03:21:49 +0000