From 6bab0393c42857232ce1194e5283a797ec4c6231 Mon Sep 17 00:00:00 2001 From: saghul Date: Thu, 23 Feb 2012 23:15:07 +0100 Subject: [PATCH] Added support for parsing NAPTR records --- Makefile.inc | 2 + ares.h | 14 +++ ares_data.c | 24 +++++ ares_data.h | 10 ++- ares_parse_naptr_reply.3 | 83 +++++++++++++++++ ares_parse_naptr_reply.c | 188 +++++++++++++++++++++++++++++++++++++++ vc/cares/vc6cares.dsp | 4 + 7 files changed, 321 insertions(+), 4 deletions(-) create mode 100644 ares_parse_naptr_reply.3 create mode 100644 ares_parse_naptr_reply.c diff --git a/Makefile.inc b/Makefile.inc index d6d4851..def54cb 100644 --- a/Makefile.inc +++ b/Makefile.inc @@ -25,6 +25,7 @@ CSOURCES = ares__close_sockets.c \ ares_parse_a_reply.c \ ares_parse_aaaa_reply.c \ ares_parse_mx_reply.c \ + ares_parse_naptr_reply.c \ ares_parse_ns_reply.c \ ares_parse_ptr_reply.c \ ares_parse_srv_reply.c \ @@ -93,6 +94,7 @@ MANPAGES = ares_cancel.3 \ ares_parse_a_reply.3 \ ares_parse_aaaa_reply.3 \ ares_parse_mx_reply.3 \ + ares_parse_naptr_reply.3 \ ares_parse_ns_reply.3 \ ares_parse_ptr_reply.3 \ ares_parse_srv_reply.3 \ diff --git a/ares.h b/ares.h index 2b38303..a3abec8 100644 --- a/ares.h +++ b/ares.h @@ -465,6 +465,16 @@ struct ares_txt_reply { size_t length; /* length excludes null termination */ }; +struct ares_naptr_reply { + struct ares_naptr_reply *next; + unsigned char *flags; + unsigned char *service; + unsigned char *regexp; + char *replacement; + unsigned short order; + unsigned short preference; +}; + /* ** Parse the buffer, starting at *abuf and of length alen bytes, previously ** obtained from an ares_search call. Put the results in *host, if nonnull. @@ -508,6 +518,10 @@ CARES_EXTERN int ares_parse_txt_reply(const unsigned char* abuf, int alen, struct ares_txt_reply** txt_out); +CARES_EXTERN int ares_parse_naptr_reply(const unsigned char* abuf, + int alen, + struct ares_naptr_reply** naptr_out); + CARES_EXTERN void ares_free_string(void *str); CARES_EXTERN void ares_free_hostent(struct hostent *host); diff --git a/ares_data.c b/ares_data.c index a2477be..b062839 100644 --- a/ares_data.c +++ b/ares_data.c @@ -92,6 +92,20 @@ void ares_free_data(void *dataptr) ares_free_data(ptr->data.addr_node.next); break; + case ARES_DATATYPE_NAPTR_REPLY: + + if (ptr->data.naptr_reply.next) + ares_free_data(ptr->data.naptr_reply.next); + if (ptr->data.naptr_reply.flags) + free(ptr->data.naptr_reply.flags); + if (ptr->data.naptr_reply.service) + free(ptr->data.naptr_reply.service); + if (ptr->data.naptr_reply.regexp); + free(ptr->data.naptr_reply.regexp); + if (ptr->data.naptr_reply.replacement); + free(ptr->data.naptr_reply.replacement); + break; + default: return; } @@ -148,6 +162,16 @@ void *ares_malloc_data(ares_datatype type) sizeof(ptr->data.addr_node.addrV6)); break; + case ARES_DATATYPE_NAPTR_REPLY: + ptr->data.naptr_reply.next = NULL; + ptr->data.naptr_reply.flags = NULL; + ptr->data.naptr_reply.service; + ptr->data.naptr_reply.regexp = NULL; + ptr->data.naptr_reply.replacement = NULL; + ptr->data.naptr_reply.order = 0; + ptr->data.naptr_reply.preference = 0; + break; + default: free(ptr); return NULL; diff --git a/ares_data.h b/ares_data.h index de1608b..a6acd20 100644 --- a/ares_data.h +++ b/ares_data.h @@ -20,6 +20,7 @@ typedef enum { ARES_DATATYPE_TXT_REPLY, /* struct ares_txt_reply - introduced in 1.7.0 */ ARES_DATATYPE_ADDR_NODE, /* struct ares_addr_node - introduced in 1.7.1 */ ARES_DATATYPE_MX_REPLY, /* struct ares_mx_reply - introduced in 1.7.2 */ + ARES_DATATYPE_NAPTR_REPLY,/* struct ares_naptr_reply - introduced in 1.7.6 */ #if 0 ARES_DATATYPE_ADDR6TTL, /* struct ares_addrttl */ ARES_DATATYPE_ADDRTTL, /* struct ares_addr6ttl */ @@ -53,10 +54,11 @@ struct ares_data { ares_datatype type; /* Actual data type identifier. */ unsigned int mark; /* Private ares_data signature. */ union { - struct ares_txt_reply txt_reply; - struct ares_srv_reply srv_reply; - struct ares_addr_node addr_node; - struct ares_mx_reply mx_reply; + struct ares_txt_reply txt_reply; + struct ares_srv_reply srv_reply; + struct ares_addr_node addr_node; + struct ares_mx_reply mx_reply; + struct ares_naptr_reply naptr_reply; } data; }; diff --git a/ares_parse_naptr_reply.3 b/ares_parse_naptr_reply.3 new file mode 100644 index 0000000..2a5f1e5 --- /dev/null +++ b/ares_parse_naptr_reply.3 @@ -0,0 +1,83 @@ +.\" +.\" Copyright 1998 by the Massachusetts Institute of Technology. +.\" +.\" Permission to use, copy, modify, and distribute this +.\" software and its documentation for any purpose and without +.\" fee is hereby granted, provided that the above copyright +.\" notice appear in all copies and that both that copyright +.\" notice and this permission notice appear in supporting +.\" documentation, and that the name of M.I.T. not be used in +.\" advertising or publicity pertaining to distribution of the +.\" software without specific, written prior permission. +.\" M.I.T. makes no representations about the suitability of +.\" this software for any purpose. It is provided "as is" +.\" without express or implied warranty. +.\" +.TH ARES_PARSE_NAPTR_REPLY 3 "23 February 2012" +.SH NAME +ares_parse_naptr_reply \- Parse a reply to a DNS query of type NAPTR +.SH SYNOPSIS +.nf +.B #include +.PP +.B int ares_parse_naptr_reply(const unsigned char* \fIabuf\fP, int \fIalen\fP, +.B struct ares_naptr_reply** \fInaptr_out\fP); +.fi +.SH DESCRIPTION +The +.B ares_parse_naptr_reply +function parses the response to a query of type NAPTR into a +linked list of +.I struct ares_naptr_reply +The parameters +.I abuf +and +.I alen +give the contents of the response. The result is stored in allocated +memory and a pointer to it stored into the variable pointed to by +.IR naptr_out . +It is the caller's responsibility to free the resulting +.IR naptr_out +structure when it is no longer needed using the function +.B ares_free_data +.PP +The structure +.I ares_naptr_reply +contains the following fields: +.sp +.in +4n +.nf +struct ares_naptr_reply { + struct ares_naptr_reply *next; + unsigned char *flags; + unsigned char *service; + unsigned char *regexp; + char *replacement; + unsigned short order; + unsigned short preference; +}; +.fi +.in +.PP +.SH RETURN VALUES +.B ares_parse_naptr_reply +can return any of the following values: +.TP 15 +.B ARES_SUCCESS +The response was successfully parsed. +.TP 15 +.B ARES_EBADRESP +The response was malformatted. +.TP 15 +.B ARES_ENODATA +The response did not contain an answer to the query. +.TP 15 +.B ARES_ENOMEM +Memory was exhausted. +.SH AVAILABILITY +This function was first introduced in c-ares version 1.7.6. +.SH SEE ALSO +.BR ares_query (3) +.BR ares_free_data (3) +.SH AUTHOR +Written by Jakub Hrozek , on behalf of Red Hat, Inc http://www.redhat.com diff --git a/ares_parse_naptr_reply.c b/ares_parse_naptr_reply.c new file mode 100644 index 0000000..6a9d09e --- /dev/null +++ b/ares_parse_naptr_reply.c @@ -0,0 +1,188 @@ + +/* Copyright 1998 by the Massachusetts Institute of Technology. + * Copyright (C) 2009 by Jakub Hrozek + * + * Permission to use, copy, modify, and distribute this + * software and its documentation for any purpose and without + * fee is hereby granted, provided that the above copyright + * notice appear in all copies and that both that copyright + * notice and this permission notice appear in supporting + * documentation, and that the name of M.I.T. not be used in + * advertising or publicity pertaining to distribution of the + * software without specific, written prior permission. + * M.I.T. makes no representations about the suitability of + * this software for any purpose. It is provided "as is" + * without express or implied warranty. + */ + +#include "ares_setup.h" + +#ifdef HAVE_SYS_SOCKET_H +# include +#endif +#ifdef HAVE_NETINET_IN_H +# include +#endif +#ifdef HAVE_NETDB_H +# include +#endif +#ifdef HAVE_ARPA_INET_H +# include +#endif +#ifdef HAVE_ARPA_NAMESER_H +# include +#else +# include "nameser.h" +#endif +#ifdef HAVE_ARPA_NAMESER_COMPAT_H +# include +#endif + +#include +#include +#include "ares.h" +#include "ares_dns.h" +#include "ares_data.h" +#include "ares_private.h" + +/* AIX portability check */ +#ifndef T_NAPTR + #define T_NAPTR 35 /* naming authority pointer */ +#endif + +int +ares_parse_naptr_reply (const unsigned char *abuf, int alen, + struct ares_naptr_reply **naptr_out) +{ + unsigned int qdcount, ancount, i; + const unsigned char *aptr, *vptr; + int status, rr_type, rr_class, rr_len; + long len; + char *hostname = NULL, *rr_name = NULL; + struct ares_naptr_reply *naptr_head = NULL; + struct ares_naptr_reply *naptr_last = NULL; + struct ares_naptr_reply *naptr_curr; + + /* Set *naptr_out to NULL for all failure cases. */ + *naptr_out = NULL; + + /* Give up if abuf doesn't have room for a header. */ + if (alen < HFIXEDSZ) + return ARES_EBADRESP; + + /* Fetch the question and answer count from the header. */ + qdcount = DNS_HEADER_QDCOUNT (abuf); + ancount = DNS_HEADER_ANCOUNT (abuf); + if (qdcount != 1) + return ARES_EBADRESP; + if (ancount == 0) + return ARES_ENODATA; + + /* Expand the name from the question, and skip past the question. */ + aptr = abuf + HFIXEDSZ; + status = ares_expand_name (aptr, abuf, alen, &hostname, &len); + if (status != ARES_SUCCESS) + return status; + + if (aptr + len + QFIXEDSZ > abuf + alen) + { + free (hostname); + return ARES_EBADRESP; + } + aptr += len + QFIXEDSZ; + + /* Examine each answer resource record (RR) in turn. */ + for (i = 0; i < ancount; i++) + { + /* Decode the RR up to the data field. */ + status = ares_expand_name (aptr, abuf, alen, &rr_name, &len); + if (status != ARES_SUCCESS) + { + break; + } + aptr += len; + if (aptr + RRFIXEDSZ > abuf + alen) + { + status = ARES_EBADRESP; + break; + } + rr_type = DNS_RR_TYPE (aptr); + rr_class = DNS_RR_CLASS (aptr); + rr_len = DNS_RR_LEN (aptr); + aptr += RRFIXEDSZ; + + /* Check if we are really looking at a NAPTR record */ + if (rr_class == C_IN && rr_type == T_NAPTR) + { + /* parse the NAPTR record itself */ + + /* Allocate storage for this NAPTR answer appending it to the list */ + naptr_curr = ares_malloc_data(ARES_DATATYPE_NAPTR_REPLY); + if (!naptr_curr) + { + status = ARES_ENOMEM; + break; + } + if (naptr_last) + { + naptr_last->next = naptr_curr; + } + else + { + naptr_head = naptr_curr; + } + naptr_last = naptr_curr; + + vptr = aptr; + naptr_curr->order = DNS__16BIT(vptr); + vptr += sizeof(unsigned short); + naptr_curr->preference = DNS__16BIT(vptr); + vptr += sizeof(unsigned short); + + status = ares_expand_string(vptr, abuf, alen, &naptr_curr->flags, &len); + if (status != ARES_SUCCESS) + break; + vptr += len; + + status = ares_expand_string(vptr, abuf, alen, &naptr_curr->service, &len); + if (status != ARES_SUCCESS) + break; + vptr += len; + + status = ares_expand_string(vptr, abuf, alen, &naptr_curr->regexp, &len); + if (status != ARES_SUCCESS) + break; + vptr += len; + + status = ares_expand_name(vptr, abuf, alen, &naptr_curr->replacement, &len); + if (status != ARES_SUCCESS) + break; + } + + /* Don't lose memory in the next iteration */ + free (rr_name); + rr_name = NULL; + + /* Move on to the next record */ + aptr += rr_len; + } + + if (hostname) + free (hostname); + if (rr_name) + free (rr_name); + + /* clean up on error */ + if (status != ARES_SUCCESS) + { + if (naptr_head) + ares_free_data (naptr_head); + return status; + } + + /* everything looks fine, return the data */ + *naptr_out = naptr_head; + + return ARES_SUCCESS; +} + diff --git a/vc/cares/vc6cares.dsp b/vc/cares/vc6cares.dsp index 595a0f1..fa7101e 100644 --- a/vc/cares/vc6cares.dsp +++ b/vc/cares/vc6cares.dsp @@ -254,6 +254,10 @@ SOURCE=..\..\ares_parse_mx_reply.c # End Source File # Begin Source File +SOURCE=..\..\ares_parse_naptr_reply.c +# End Source File +# Begin Source File + SOURCE=..\..\ares_parse_ns_reply.c # End Source File # Begin Source File