Adding upstream version 1:9.11.5.P4+dfsg.upstream/1%9.11.5.P4+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 571 insertions, 0 deletions

diff --git a/lib/lwres/lwresutil.c b/lib/lwres/lwresutil.c
new file mode 100644
index 0000000..3ddc8d5
--- /dev/null
+++ b/lib/lwres/lwresutil.c
@@ -0,0 +1,571 @@
+/*
+ * 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: lwresutil.c,v 1.34 2007/06/19 23:47:22 tbox Exp $ */
+
+/*! \file */
+
+/**
+ *    lwres_string_parse() retrieves a DNS-encoded string starting the
+ *    current pointer of lightweight resolver buffer b: i.e. b->current.
+ *    When the function returns, the address of the first byte of the
+ *    encoded string is returned via *c and the length of that string is
+ *    given by *len. The buffer's current pointer is advanced to point at
+ *    the character following the string length, the encoded string, and
+ *    the trailing NULL character.
+ *
+ *    lwres_addr_parse() extracts an address from the buffer b. The
+ *    buffer's current pointer b->current is presumed to point at an
+ *    encoded address: the address preceded by a 32-bit protocol family
+ *    identifier and a 16-bit length field. The encoded address is copied
+ *    to addr->address and addr->length indicates the size in bytes of
+ *    the address that was copied. b->current is advanced to point at the
+ *  next byte of available data in the buffer following the encoded
+ *    address.
+ *
+ *    lwres_getaddrsbyname() and lwres_getnamebyaddr() use the
+ *    lwres_gnbaresponse_t structure defined below:
+ *
+ * \code
+ * 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
+ *
+ *    The contents of this structure are not manipulated directly but
+ *    they are controlled through the \link lwres_gabn.c lwres_gabn*\endlink functions.
+ *
+ *    The lightweight resolver uses lwres_getaddrsbyname() to perform
+ *    foward lookups. Hostname name is looked up using the resolver
+ *    context ctx for memory allocation. addrtypes is a bitmask
+ *    indicating which type of addresses are to be looked up. Current
+ *    values for this bitmask are #LWRES_ADDRTYPE_V4 for IPv4 addresses
+ *    and #LWRES_ADDRTYPE_V6 for IPv6 addresses. Results of the lookup are
+ *    returned in *structp.
+ *
+ *    lwres_getnamebyaddr() performs reverse lookups. Resolver context
+ *    ctx is used for memory allocation. The address type is indicated by
+ *    addrtype: #LWRES_ADDRTYPE_V4 or #LWRES_ADDRTYPE_V6. The address to be
+ *    looked up is given by addr and its length is addrlen bytes. The
+ *    result of the function call is made available through *structp.
+ *
+ * \section lwresutil_return Return Values
+ *
+ *    Successful calls to lwres_string_parse() and lwres_addr_parse()
+ *    return #LWRES_R_SUCCESS. Both functions return #LWRES_R_FAILURE if
+ *    the buffer is corrupt or #LWRES_R_UNEXPECTEDEND if the buffer has
+ *    less space than expected for the components of the encoded string
+ *    or address.
+ *
+ * lwres_getaddrsbyname() returns #LWRES_R_SUCCESS on success and it
+ *    returns #LWRES_R_NOTFOUND if the hostname name could not be found.
+ *
+ *    #LWRES_R_SUCCESS is returned by a successful call to
+ *    lwres_getnamebyaddr().
+ *
+ *    Both lwres_getaddrsbyname() and lwres_getnamebyaddr() return
+ *    #LWRES_R_NOMEMORY when memory allocation requests fail and
+ *    #LWRES_R_UNEXPECTEDEND if the buffers used for sending queries and
+ *    receiving replies are too small.
+ *
+ * \section lwresutil_see See Also
+ *
+ *    lwbuffer.c, lwres_gabn.c
+ */
+
+#include <config.h>
+
+#include <assert.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <lwres/lwbuffer.h>
+#include <lwres/lwres.h>
+#include <lwres/result.h>
+
+#include "assert_p.h"
+#include "context_p.h"
+
+/*% Parse data. */
+/*!
+ * Requires:
+ *
+ *	The "current" pointer in "b" points to encoded raw data.
+ *
+ * Ensures:
+ *
+ *	The address of the first byte of the data is returned via "p",
+ *	and the length is returned via "len".  If NULL, they are not
+ *	set.
+ *
+ *	On return, the current pointer of "b" will point to the character
+ *	following the data length and the data.
+ *
+ */
+lwres_result_t
+lwres_data_parse(lwres_buffer_t *b, unsigned char **p, uint16_t *len)
+{
+	uint16_t datalen;
+	unsigned char *data;
+
+	REQUIRE(b != NULL);
+
+	/*
+	 * Pull off the length (2 bytes)
+	 */
+	if (!SPACE_REMAINING(b, 2))
+		return (LWRES_R_UNEXPECTEDEND);
+	datalen = lwres_buffer_getuint16(b);
+
+	/*
+	 * Set the pointer to this string to the right place, then
+	 * advance the buffer pointer.
+	 */
+	if (!SPACE_REMAINING(b, datalen))
+		return (LWRES_R_UNEXPECTEDEND);
+	data = b->base + b->current;
+	lwres_buffer_forward(b, datalen);
+
+	if (len != NULL)
+		*len = datalen;
+	if (p != NULL)
+		*p = data;
+
+	return (LWRES_R_SUCCESS);
+}
+
+/*% Retrieves a DNS-encoded string. */
+/*!
+ * Requires:
+ *
+ *	The "current" pointer in "b" point to an encoded string.
+ *
+ * Ensures:
+ *
+ *	The address of the first byte of the string is returned via "c",
+ *	and the length is returned via "len".  If NULL, they are not
+ *	set.
+ *
+ *	On return, the current pointer of "b" will point to the character
+ *	following the string length, the string, and the trailing NULL.
+ *
+ */
+lwres_result_t
+lwres_string_parse(lwres_buffer_t *b, char **c, uint16_t *len)
+{
+	uint16_t datalen;
+	char *string;
+
+	REQUIRE(b != NULL);
+
+	/*
+	 * Pull off the length (2 bytes)
+	 */
+	if (!SPACE_REMAINING(b, 2))
+		return (LWRES_R_UNEXPECTEDEND);
+	datalen = lwres_buffer_getuint16(b);
+
+	/*
+	 * Set the pointer to this string to the right place, then
+	 * advance the buffer pointer.
+	 */
+	if (!SPACE_REMAINING(b, datalen))
+		return (LWRES_R_UNEXPECTEDEND);
+	string = (char *)b->base + b->current;
+	lwres_buffer_forward(b, datalen);
+
+	/*
+	 * Skip the "must be zero" byte.
+	 */
+	if (!SPACE_REMAINING(b, 1))
+		return (LWRES_R_UNEXPECTEDEND);
+	if (0 != lwres_buffer_getuint8(b))
+		return (LWRES_R_FAILURE);
+
+	if (len != NULL)
+		*len = datalen;
+	if (c != NULL)
+		*c = string;
+
+	return (LWRES_R_SUCCESS);
+}
+
+/*% Extracts an address from the buffer b. */
+lwres_result_t
+lwres_addr_parse(lwres_buffer_t *b, lwres_addr_t *addr)
+{
+	REQUIRE(addr != NULL);
+
+	if (!SPACE_REMAINING(b, 6))
+		return (LWRES_R_UNEXPECTEDEND);
+
+	addr->family = lwres_buffer_getuint32(b);
+	addr->length = lwres_buffer_getuint16(b);
+
+	if (!SPACE_REMAINING(b, addr->length))
+		return (LWRES_R_UNEXPECTEDEND);
+	if (addr->length > LWRES_ADDR_MAXLEN)
+		return (LWRES_R_FAILURE);
+
+	lwres_buffer_getmem(b, addr->address, addr->length);
+
+	return (LWRES_R_SUCCESS);
+}
+
+/*% Used to perform forward lookups. */
+lwres_result_t
+lwres_getaddrsbyname(lwres_context_t *ctx, const char *name,
+		     uint32_t addrtypes, lwres_gabnresponse_t **structp)
+{
+	lwres_gabnrequest_t request;
+	lwres_gabnresponse_t *response;
+	int ret;
+	int recvlen;
+	lwres_buffer_t b_in, b_out;
+	lwres_lwpacket_t pkt;
+	uint32_t serial;
+	char *buffer;
+	char target_name[1024];
+	unsigned int target_length;
+
+	REQUIRE(ctx != NULL);
+	REQUIRE(name != NULL);
+	REQUIRE(addrtypes != 0);
+	REQUIRE(structp != NULL && *structp == NULL);
+
+	b_in.base = NULL;
+	b_out.base = NULL;
+	response = NULL;
+	buffer = NULL;
+	serial = lwres_context_nextserial(ctx);
+
+	buffer = CTXMALLOC(LWRES_RECVLENGTH);
+	if (buffer == NULL) {
+		ret = LWRES_R_NOMEMORY;
+		goto out;
+	}
+
+	target_length = strlen(name);
+	if (target_length >= sizeof(target_name))
+		return (LWRES_R_FAILURE);
+	strcpy(target_name, name); /* strcpy is safe */
+
+	/*
+	 * Set up our request and render it to a buffer.
+	 */
+	request.flags = 0;
+	request.addrtypes = addrtypes;
+	request.name = target_name;
+	request.namelen = target_length;
+	pkt.pktflags = 0;
+	pkt.serial = serial;
+	pkt.result = 0;
+	pkt.recvlength = LWRES_RECVLENGTH;
+
+ again:
+	ret = lwres_gabnrequest_render(ctx, &request, &pkt, &b_out);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	ret = lwres_context_sendrecv(ctx, b_out.base, b_out.length, buffer,
+				     LWRES_RECVLENGTH, &recvlen);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	lwres_buffer_init(&b_in, buffer, recvlen);
+	b_in.used = recvlen;
+
+	/*
+	 * Parse the packet header.
+	 */
+	ret = lwres_lwpacket_parseheader(&b_in, &pkt);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	/*
+	 * Sanity check.
+	 */
+	if (pkt.serial != serial)
+		goto again;
+	if (pkt.opcode != LWRES_OPCODE_GETADDRSBYNAME)
+		goto again;
+
+	/*
+	 * Free what we've transmitted
+	 */
+	CTXFREE(b_out.base, b_out.length);
+	b_out.base = NULL;
+	b_out.length = 0;
+
+	if (pkt.result != LWRES_R_SUCCESS) {
+		ret = pkt.result;
+		goto out;
+	}
+
+	/*
+	 * Parse the response.
+	 */
+	ret = lwres_gabnresponse_parse(ctx, &b_in, &pkt, &response);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+	response->base = buffer;
+	response->baselen = LWRES_RECVLENGTH;
+	buffer = NULL; /* don't free this below */
+
+	*structp = response;
+	return (LWRES_R_SUCCESS);
+
+ out:
+	if (b_out.base != NULL)
+		CTXFREE(b_out.base, b_out.length);
+	if (buffer != NULL)
+		CTXFREE(buffer, LWRES_RECVLENGTH);
+	if (response != NULL)
+		lwres_gabnresponse_free(ctx, &response);
+
+	return (ret);
+}
+
+
+/*% Used to perform reverse lookups. */
+lwres_result_t
+lwres_getnamebyaddr(lwres_context_t *ctx, uint32_t addrtype,
+		    uint16_t addrlen, const unsigned char *addr,
+		    lwres_gnbaresponse_t **structp)
+{
+	lwres_gnbarequest_t request;
+	lwres_gnbaresponse_t *response;
+	int ret;
+	int recvlen;
+	lwres_buffer_t b_in, b_out;
+	lwres_lwpacket_t pkt;
+	uint32_t serial;
+	char *buffer;
+
+	REQUIRE(ctx != NULL);
+	REQUIRE(addrtype != 0);
+	REQUIRE(addrlen != 0);
+	REQUIRE(addr != NULL);
+	REQUIRE(structp != NULL && *structp == NULL);
+
+	b_in.base = NULL;
+	b_out.base = NULL;
+	response = NULL;
+	buffer = NULL;
+	serial = lwres_context_nextserial(ctx);
+
+	buffer = CTXMALLOC(LWRES_RECVLENGTH);
+	if (buffer == NULL) {
+		ret = LWRES_R_NOMEMORY;
+		goto out;
+	}
+
+	/*
+	 * Set up our request and render it to a buffer.
+	 */
+	request.flags = 0;
+	request.addr.family = addrtype;
+	request.addr.length = addrlen;
+	memmove(request.addr.address, addr, addrlen);
+	pkt.pktflags = 0;
+	pkt.serial = serial;
+	pkt.result = 0;
+	pkt.recvlength = LWRES_RECVLENGTH;
+
+ again:
+	ret = lwres_gnbarequest_render(ctx, &request, &pkt, &b_out);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	ret = lwres_context_sendrecv(ctx, b_out.base, b_out.length, buffer,
+				     LWRES_RECVLENGTH, &recvlen);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	lwres_buffer_init(&b_in, buffer, recvlen);
+	b_in.used = recvlen;
+
+	/*
+	 * Parse the packet header.
+	 */
+	ret = lwres_lwpacket_parseheader(&b_in, &pkt);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	/*
+	 * Sanity check.
+	 */
+	if (pkt.serial != serial)
+		goto again;
+	if (pkt.opcode != LWRES_OPCODE_GETNAMEBYADDR)
+		goto again;
+
+	/*
+	 * Free what we've transmitted
+	 */
+	CTXFREE(b_out.base, b_out.length);
+	b_out.base = NULL;
+	b_out.length = 0;
+
+	if (pkt.result != LWRES_R_SUCCESS) {
+		ret = pkt.result;
+		goto out;
+	}
+
+	/*
+	 * Parse the response.
+	 */
+	ret = lwres_gnbaresponse_parse(ctx, &b_in, &pkt, &response);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+	response->base = buffer;
+	response->baselen = LWRES_RECVLENGTH;
+	buffer = NULL; /* don't free this below */
+
+	*structp = response;
+	return (LWRES_R_SUCCESS);
+
+ out:
+	if (b_out.base != NULL)
+		CTXFREE(b_out.base, b_out.length);
+	if (buffer != NULL)
+		CTXFREE(buffer, LWRES_RECVLENGTH);
+	if (response != NULL)
+		lwres_gnbaresponse_free(ctx, &response);
+
+	return (ret);
+}
+
+/*% Get rdata by name. */
+lwres_result_t
+lwres_getrdatabyname(lwres_context_t *ctx, const char *name,
+		     uint16_t rdclass, uint16_t rdtype,
+		     uint32_t flags, lwres_grbnresponse_t **structp)
+{
+	int ret;
+	int recvlen;
+	lwres_buffer_t b_in, b_out;
+	lwres_lwpacket_t pkt;
+	uint32_t serial;
+	char *buffer;
+	lwres_grbnrequest_t request;
+	lwres_grbnresponse_t *response;
+	char target_name[1024];
+	unsigned int target_length;
+
+	REQUIRE(ctx != NULL);
+	REQUIRE(name != NULL);
+	REQUIRE(structp != NULL && *structp == NULL);
+
+	b_in.base = NULL;
+	b_out.base = NULL;
+	response = NULL;
+	buffer = NULL;
+	serial = lwres_context_nextserial(ctx);
+
+	buffer = CTXMALLOC(LWRES_RECVLENGTH);
+	if (buffer == NULL) {
+		ret = LWRES_R_NOMEMORY;
+		goto out;
+	}
+
+	target_length = strlen(name);
+	if (target_length >= sizeof(target_name))
+		return (LWRES_R_FAILURE);
+	strcpy(target_name, name); /* strcpy is safe */
+
+	/*
+	 * Set up our request and render it to a buffer.
+	 */
+	request.rdclass = rdclass;
+	request.rdtype = rdtype;
+	request.flags = flags;
+	request.name = target_name;
+	request.namelen = target_length;
+	pkt.pktflags = 0;
+	pkt.serial = serial;
+	pkt.result = 0;
+	pkt.recvlength = LWRES_RECVLENGTH;
+
+ again:
+	ret = lwres_grbnrequest_render(ctx, &request, &pkt, &b_out);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	ret = lwres_context_sendrecv(ctx, b_out.base, b_out.length, buffer,
+				     LWRES_RECVLENGTH, &recvlen);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	lwres_buffer_init(&b_in, buffer, recvlen);
+	b_in.used = recvlen;
+
+	/*
+	 * Parse the packet header.
+	 */
+	ret = lwres_lwpacket_parseheader(&b_in, &pkt);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+
+	/*
+	 * Sanity check.
+	 */
+	if (pkt.serial != serial)
+		goto again;
+	if (pkt.opcode != LWRES_OPCODE_GETRDATABYNAME)
+		goto again;
+
+	/*
+	 * Free what we've transmitted
+	 */
+	CTXFREE(b_out.base, b_out.length);
+	b_out.base = NULL;
+	b_out.length = 0;
+
+	if (pkt.result != LWRES_R_SUCCESS) {
+		ret = pkt.result;
+		goto out;
+	}
+
+	/*
+	 * Parse the response.
+	 */
+	ret = lwres_grbnresponse_parse(ctx, &b_in, &pkt, &response);
+	if (ret != LWRES_R_SUCCESS)
+		goto out;
+	response->base = buffer;
+	response->baselen = LWRES_RECVLENGTH;
+	buffer = NULL; /* don't free this below */
+
+	*structp = response;
+	return (LWRES_R_SUCCESS);
+
+ out:
+	if (b_out.base != NULL)
+		CTXFREE(b_out.base, b_out.length);
+	if (buffer != NULL)
+		CTXFREE(buffer, LWRES_RECVLENGTH);
+	if (response != NULL)
+		lwres_grbnresponse_free(ctx, &response);
+
+	return (ret);
+}