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Diffstat (limited to 'contrib/bind9/lib/lwres/context.c')
| -rw-r--r-- | contrib/bind9/lib/lwres/context.c | 482 |
1 files changed, 0 insertions, 482 deletions
diff --git a/contrib/bind9/lib/lwres/context.c b/contrib/bind9/lib/lwres/context.c deleted file mode 100644 index c731bb7..0000000 --- a/contrib/bind9/lib/lwres/context.c +++ /dev/null @@ -1,482 +0,0 @@ -/* - * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") - * Copyright (C) 2000, 2001, 2003 Internet Software Consortium. - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* $Id: context.c,v 1.45.18.7 2007/08/28 07:20:06 tbox Exp $ */ - -/*! \file context.c - lwres_context_create() creates a #lwres_context_t structure for use in - lightweight resolver operations. It holds a socket and other data - needed for communicating with a resolver daemon. The new - lwres_context_t is returned through contextp, a pointer to a - lwres_context_t pointer. This lwres_context_t pointer must initially - be NULL, and is modified to point to the newly created - lwres_context_t. - - When the lightweight resolver needs to perform dynamic memory - allocation, it will call malloc_function to allocate memory and - free_function to free it. If malloc_function and free_function are - NULL, memory is allocated using malloc and free. It is not - permitted to have a NULL malloc_function and a non-NULL free_function - or vice versa. arg is passed as the first parameter to the memory - allocation functions. If malloc_function and free_function are NULL, - arg is unused and should be passed as NULL. - - Once memory for the structure has been allocated, it is initialized - using lwres_conf_init() and returned via *contextp. - - lwres_context_destroy() destroys a #lwres_context_t, closing its - socket. contextp is a pointer to a pointer to the context that is to - be destroyed. The pointer will be set to NULL when the context has - been destroyed. - - The context holds a serial number that is used to identify resolver - request packets and associate responses with the corresponding - requests. This serial number is controlled using - lwres_context_initserial() and lwres_context_nextserial(). - lwres_context_initserial() sets the serial number for context *ctx to - serial. lwres_context_nextserial() increments the serial number and - returns the previous value. - - Memory for a lightweight resolver context is allocated and freed using - lwres_context_allocmem() and lwres_context_freemem(). These use - whatever allocations were defined when the context was created with - lwres_context_create(). lwres_context_allocmem() allocates len bytes - of memory and if successful returns a pointer to the allocated - storage. lwres_context_freemem() frees len bytes of space starting at - location mem. - - lwres_context_sendrecv() performs I/O for the context ctx. Data are - read and written from the context's socket. It writes data from - sendbase -- typically a lightweight resolver query packet -- and waits - for a reply which is copied to the receive buffer at recvbase. The - number of bytes that were written to this receive buffer is returned - in *recvd_len. - -\section context_return Return Values - - lwres_context_create() returns #LWRES_R_NOMEMORY if memory for the - struct lwres_context could not be allocated, #LWRES_R_SUCCESS - otherwise. - - Successful calls to the memory allocator lwres_context_allocmem() - return a pointer to the start of the allocated space. It returns NULL - if memory could not be allocated. - - #LWRES_R_SUCCESS is returned when lwres_context_sendrecv() completes - successfully. #LWRES_R_IOERROR is returned if an I/O error occurs and - #LWRES_R_TIMEOUT is returned if lwres_context_sendrecv() times out - waiting for a response. - -\section context_see See Also - - lwres_conf_init(), malloc, free. - */ -#include <config.h> - -#include <fcntl.h> -#include <limits.h> -#include <stdlib.h> -#include <string.h> -#include <time.h> -#include <unistd.h> - -#include <lwres/lwres.h> -#include <lwres/net.h> -#include <lwres/platform.h> - -#ifdef LWRES_PLATFORM_NEEDSYSSELECTH -#include <sys/select.h> -#endif - -#include "context_p.h" -#include "assert_p.h" - -/*! - * Some systems define the socket length argument as an int, some as size_t, - * some as socklen_t. The last is what the current POSIX standard mandates. - * This definition is here so it can be portable but easily changed if needed. - */ -#ifndef LWRES_SOCKADDR_LEN_T -#define LWRES_SOCKADDR_LEN_T unsigned int -#endif - -/*! - * Make a socket nonblocking. - */ -#ifndef MAKE_NONBLOCKING -#define MAKE_NONBLOCKING(sd, retval) \ -do { \ - retval = fcntl(sd, F_GETFL, 0); \ - if (retval != -1) { \ - retval |= O_NONBLOCK; \ - retval = fcntl(sd, F_SETFL, retval); \ - } \ -} while (0) -#endif - -LIBLWRES_EXTERNAL_DATA lwres_uint16_t lwres_udp_port = LWRES_UDP_PORT; -LIBLWRES_EXTERNAL_DATA const char *lwres_resolv_conf = LWRES_RESOLV_CONF; - -static void * -lwres_malloc(void *, size_t); - -static void -lwres_free(void *, void *, size_t); - -/*! - * lwres_result_t - */ -static lwres_result_t -context_connect(lwres_context_t *); - -/*% - * Creates a #lwres_context_t structure for use in - * lightweight resolver operations. - */ -lwres_result_t -lwres_context_create(lwres_context_t **contextp, void *arg, - lwres_malloc_t malloc_function, - lwres_free_t free_function, - unsigned int flags) -{ - lwres_context_t *ctx; - - REQUIRE(contextp != NULL && *contextp == NULL); - UNUSED(flags); - - /* - * If we were not given anything special to use, use our own - * functions. These are just wrappers around malloc() and free(). - */ - if (malloc_function == NULL || free_function == NULL) { - REQUIRE(malloc_function == NULL); - REQUIRE(free_function == NULL); - malloc_function = lwres_malloc; - free_function = lwres_free; - } - - ctx = malloc_function(arg, sizeof(lwres_context_t)); - if (ctx == NULL) - return (LWRES_R_NOMEMORY); - - /* - * Set up the context. - */ - ctx->malloc = malloc_function; - ctx->free = free_function; - ctx->arg = arg; - ctx->sock = -1; - - ctx->timeout = LWRES_DEFAULT_TIMEOUT; - ctx->serial = time(NULL); /* XXXMLG or BEW */ - - /* - * Init resolv.conf bits. - */ - lwres_conf_init(ctx); - - *contextp = ctx; - return (LWRES_R_SUCCESS); -} - -/*% -Destroys a #lwres_context_t, closing its socket. -contextp is a pointer to a pointer to the context that is -to be destroyed. The pointer will be set to NULL -when the context has been destroyed. - */ -void -lwres_context_destroy(lwres_context_t **contextp) { - lwres_context_t *ctx; - - REQUIRE(contextp != NULL && *contextp != NULL); - - ctx = *contextp; - *contextp = NULL; - - if (ctx->sock != -1) { -#ifdef WIN32 - DestroySockets(); -#endif - (void)close(ctx->sock); - ctx->sock = -1; - } - - CTXFREE(ctx, sizeof(lwres_context_t)); -} -/*% Increments the serial number and returns the previous value. */ -lwres_uint32_t -lwres_context_nextserial(lwres_context_t *ctx) { - REQUIRE(ctx != NULL); - - return (ctx->serial++); -} - -/*% Sets the serial number for context *ctx to serial. */ -void -lwres_context_initserial(lwres_context_t *ctx, lwres_uint32_t serial) { - REQUIRE(ctx != NULL); - - ctx->serial = serial; -} - -/*% Frees len bytes of space starting at location mem. */ -void -lwres_context_freemem(lwres_context_t *ctx, void *mem, size_t len) { - REQUIRE(mem != NULL); - REQUIRE(len != 0U); - - CTXFREE(mem, len); -} - -/*% Allocates len bytes of memory and if successful returns a pointer to the allocated storage. */ -void * -lwres_context_allocmem(lwres_context_t *ctx, size_t len) { - REQUIRE(len != 0U); - - return (CTXMALLOC(len)); -} - -static void * -lwres_malloc(void *arg, size_t len) { - void *mem; - - UNUSED(arg); - - mem = malloc(len); - if (mem == NULL) - return (NULL); - - memset(mem, 0xe5, len); - - return (mem); -} - -static void -lwres_free(void *arg, void *mem, size_t len) { - UNUSED(arg); - - memset(mem, 0xa9, len); - free(mem); -} - -static lwres_result_t -context_connect(lwres_context_t *ctx) { - int s; - int ret; - struct sockaddr_in sin; - struct sockaddr_in6 sin6; - struct sockaddr *sa; - LWRES_SOCKADDR_LEN_T salen; - int domain; - - if (ctx->confdata.lwnext != 0) { - memcpy(&ctx->address, &ctx->confdata.lwservers[0], - sizeof(lwres_addr_t)); - LWRES_LINK_INIT(&ctx->address, link); - } else { - /* The default is the IPv4 loopback address 127.0.0.1. */ - memset(&ctx->address, 0, sizeof(ctx->address)); - ctx->address.family = LWRES_ADDRTYPE_V4; - ctx->address.length = 4; - ctx->address.address[0] = 127; - ctx->address.address[1] = 0; - ctx->address.address[2] = 0; - ctx->address.address[3] = 1; - } - - if (ctx->address.family == LWRES_ADDRTYPE_V4) { - memcpy(&sin.sin_addr, ctx->address.address, - sizeof(sin.sin_addr)); - sin.sin_port = htons(lwres_udp_port); - sin.sin_family = AF_INET; - sa = (struct sockaddr *)&sin; - salen = sizeof(sin); - domain = PF_INET; - } else if (ctx->address.family == LWRES_ADDRTYPE_V6) { - memcpy(&sin6.sin6_addr, ctx->address.address, - sizeof(sin6.sin6_addr)); - sin6.sin6_port = htons(lwres_udp_port); - sin6.sin6_family = AF_INET6; - sa = (struct sockaddr *)&sin6; - salen = sizeof(sin6); - domain = PF_INET6; - } else - return (LWRES_R_IOERROR); - -#ifdef WIN32 - InitSockets(); -#endif - s = socket(domain, SOCK_DGRAM, IPPROTO_UDP); - if (s < 0) { -#ifdef WIN32 - DestroySockets(); -#endif - return (LWRES_R_IOERROR); - } - - ret = connect(s, sa, salen); - if (ret != 0) { -#ifdef WIN32 - DestroySockets(); -#endif - (void)close(s); - return (LWRES_R_IOERROR); - } - - MAKE_NONBLOCKING(s, ret); - if (ret < 0) { -#ifdef WIN32 - DestroySockets(); -#endif - (void)close(s); - return (LWRES_R_IOERROR); - } - - ctx->sock = s; - - return (LWRES_R_SUCCESS); -} - -int -lwres_context_getsocket(lwres_context_t *ctx) { - return (ctx->sock); -} - -lwres_result_t -lwres_context_send(lwres_context_t *ctx, - void *sendbase, int sendlen) { - int ret; - lwres_result_t lwresult; - - if (ctx->sock == -1) { - lwresult = context_connect(ctx); - if (lwresult != LWRES_R_SUCCESS) - return (lwresult); - } - - ret = sendto(ctx->sock, sendbase, sendlen, 0, NULL, 0); - if (ret < 0) - return (LWRES_R_IOERROR); - if (ret != sendlen) - return (LWRES_R_IOERROR); - - return (LWRES_R_SUCCESS); -} - -lwres_result_t -lwres_context_recv(lwres_context_t *ctx, - void *recvbase, int recvlen, - int *recvd_len) -{ - LWRES_SOCKADDR_LEN_T fromlen; - struct sockaddr_in sin; - struct sockaddr_in6 sin6; - struct sockaddr *sa; - int ret; - - if (ctx->address.family == LWRES_ADDRTYPE_V4) { - sa = (struct sockaddr *)&sin; - fromlen = sizeof(sin); - } else { - sa = (struct sockaddr *)&sin6; - fromlen = sizeof(sin6); - } - - /* - * The address of fromlen is cast to void * to shut up compiler - * warnings, namely on systems that have the sixth parameter - * prototyped as a signed int when LWRES_SOCKADDR_LEN_T is - * defined as unsigned. - */ - ret = recvfrom(ctx->sock, recvbase, recvlen, 0, sa, (void *)&fromlen); - - if (ret < 0) - return (LWRES_R_IOERROR); - - if (ret == recvlen) - return (LWRES_R_TOOLARGE); - - /* - * If we got something other than what we expect, have the caller - * wait for another packet. This can happen if an old result - * comes in, or if someone is sending us random stuff. - */ - if (ctx->address.family == LWRES_ADDRTYPE_V4) { - if (fromlen != sizeof(sin) - || memcmp(&sin.sin_addr, ctx->address.address, - sizeof(sin.sin_addr)) != 0 - || sin.sin_port != htons(lwres_udp_port)) - return (LWRES_R_RETRY); - } else { - if (fromlen != sizeof(sin6) - || memcmp(&sin6.sin6_addr, ctx->address.address, - sizeof(sin6.sin6_addr)) != 0 - || sin6.sin6_port != htons(lwres_udp_port)) - return (LWRES_R_RETRY); - } - - if (recvd_len != NULL) - *recvd_len = ret; - - return (LWRES_R_SUCCESS); -} - -/*% performs I/O for the context ctx. */ -lwres_result_t -lwres_context_sendrecv(lwres_context_t *ctx, - void *sendbase, int sendlen, - void *recvbase, int recvlen, - int *recvd_len) -{ - lwres_result_t result; - int ret2; - fd_set readfds; - struct timeval timeout; - - /* - * Type of tv_sec is 32 bits long. - */ - if (ctx->timeout <= 0x7FFFFFFFU) - timeout.tv_sec = (int)ctx->timeout; - else - timeout.tv_sec = 0x7FFFFFFF; - - timeout.tv_usec = 0; - - result = lwres_context_send(ctx, sendbase, sendlen); - if (result != LWRES_R_SUCCESS) - return (result); - again: - FD_ZERO(&readfds); - FD_SET(ctx->sock, &readfds); - ret2 = select(ctx->sock + 1, &readfds, NULL, NULL, &timeout); - - /* - * What happened with select? - */ - if (ret2 < 0) - return (LWRES_R_IOERROR); - if (ret2 == 0) - return (LWRES_R_TIMEOUT); - - result = lwres_context_recv(ctx, recvbase, recvlen, recvd_len); - if (result == LWRES_R_RETRY) - goto again; - - return (result); -} |
