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authorRajithaY <rajithax.yerrumsetty@intel.com>2017-04-25 03:31:15 -0700
committerRajitha Yerrumchetty <rajithax.yerrumsetty@intel.com>2017-05-22 06:48:08 +0000
commitbb756eebdac6fd24e8919e2c43f7d2c8c4091f59 (patch)
treeca11e03542edf2d8f631efeca5e1626d211107e3 /qemu/roms/ipxe/src/net/udp/dns.c
parenta14b48d18a9ed03ec191cf16b162206998a895ce (diff)
Adding qemu as a submodule of KVMFORNFV
This Patch includes the changes to add qemu as a submodule to kvmfornfv repo and make use of the updated latest qemu for the execution of all testcase Change-Id: I1280af507a857675c7f81d30c95255635667bdd7 Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/net/udp/dns.c')
-rw-r--r--qemu/roms/ipxe/src/net/udp/dns.c1156
1 files changed, 0 insertions, 1156 deletions
diff --git a/qemu/roms/ipxe/src/net/udp/dns.c b/qemu/roms/ipxe/src/net/udp/dns.c
deleted file mode 100644
index 2d77477f6..000000000
--- a/qemu/roms/ipxe/src/net/udp/dns.c
+++ /dev/null
@@ -1,1156 +0,0 @@
-/*
- * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
- *
- * Portions copyright (C) 2004 Anselm M. Hoffmeister
- * <stockholm@users.sourceforge.net>.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- *
- * You can also choose to distribute this program under the terms of
- * the Unmodified Binary Distribution Licence (as given in the file
- * COPYING.UBDL), provided that you have satisfied its requirements.
- */
-
-FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
-
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <ctype.h>
-#include <errno.h>
-#include <byteswap.h>
-#include <ipxe/refcnt.h>
-#include <ipxe/iobuf.h>
-#include <ipxe/xfer.h>
-#include <ipxe/open.h>
-#include <ipxe/resolv.h>
-#include <ipxe/retry.h>
-#include <ipxe/tcpip.h>
-#include <ipxe/settings.h>
-#include <ipxe/features.h>
-#include <ipxe/dhcp.h>
-#include <ipxe/dhcpv6.h>
-#include <ipxe/dns.h>
-
-/** @file
- *
- * DNS protocol
- *
- */
-
-FEATURE ( FEATURE_PROTOCOL, "DNS", DHCP_EB_FEATURE_DNS, 1 );
-
-/* Disambiguate the various error causes */
-#define ENXIO_NO_RECORD __einfo_error ( EINFO_ENXIO_NO_RECORD )
-#define EINFO_ENXIO_NO_RECORD \
- __einfo_uniqify ( EINFO_ENXIO, 0x01, "DNS name does not exist" )
-#define ENXIO_NO_NAMESERVER __einfo_error ( EINFO_ENXIO_NO_NAMESERVER )
-#define EINFO_ENXIO_NO_NAMESERVER \
- __einfo_uniqify ( EINFO_ENXIO, 0x02, "No DNS servers available" )
-
-/** The DNS server */
-static union {
- struct sockaddr sa;
- struct sockaddr_tcpip st;
- struct sockaddr_in sin;
- struct sockaddr_in6 sin6;
-} nameserver = {
- .st = {
- .st_port = htons ( DNS_PORT ),
- },
-};
-
-/** The DNS search list */
-static struct dns_name dns_search;
-
-/**
- * Encode a DNS name using RFC1035 encoding
- *
- * @v string DNS name as a string
- * @v name DNS name to fill in
- * @ret len Length of DNS name, or negative error
- */
-int dns_encode ( const char *string, struct dns_name *name ) {
- uint8_t *start = ( name->data + name->offset );
- uint8_t *end = ( name->data + name->len );
- uint8_t *dst = start;
- size_t len = 0;
- char c;
-
- /* Encode name */
- while ( ( c = *(string++) ) ) {
-
- /* Handle '.' separators */
- if ( c == '.' ) {
-
- /* Reject consecutive '.' */
- if ( ( len == 0 ) && ( dst != start ) )
- return -EINVAL;
-
- /* Terminate if this is the trailing '.' */
- if ( *string == '\0' )
- break;
-
- /* Reject initial non-terminating '.' */
- if ( len == 0 )
- return -EINVAL;
-
- /* Reset length */
- len = 0;
-
- } else {
-
- /* Increment length */
- len++;
-
- /* Check for overflow */
- if ( len > DNS_MAX_LABEL_LEN )
- return -EINVAL;
- }
-
- /* Copy byte, update length */
- if ( ++dst < end ) {
- *dst = c;
- dst[-len] = len;
- }
- }
-
- /* Add terminating root marker */
- if ( len )
- dst++;
- if ( dst < end )
- *dst = '\0';
- dst++;
-
- return ( dst - start );
-}
-
-/**
- * Find start of valid label within an RFC1035-encoded DNS name
- *
- * @v name DNS name
- * @v offset Current offset
- * @ret offset Offset of label, or negative error
- */
-static int dns_label ( struct dns_name *name, size_t offset ) {
- const uint8_t *byte;
- const uint16_t *word;
- size_t len;
- size_t ptr;
-
- while ( 1 ) {
-
- /* Fail if we have overrun the DNS name */
- if ( ( offset + sizeof ( *byte) ) > name->len )
- return -EINVAL;
- byte = ( name->data + offset );
-
- /* Follow compression pointer, if applicable */
- if ( DNS_IS_COMPRESSED ( *byte ) ) {
-
- /* Fail if we have overrun the DNS name */
- if ( ( offset + sizeof ( *word ) ) > name->len )
- return -EINVAL;
- word = ( name->data + offset );
-
- /* Extract pointer to new offset */
- ptr = DNS_COMPRESSED_OFFSET ( ntohs ( *word ) );
-
- /* Fail if pointer does not point backwards.
- * (This guarantees termination of the
- * function.)
- */
- if ( ptr >= offset )
- return -EINVAL;
-
- /* Continue from new offset */
- offset = ptr;
- continue;
- }
-
- /* Fail if we have overrun the DNS name */
- len = *byte;
- if ( ( offset + sizeof ( *byte ) + len ) > name->len )
- return -EINVAL;
-
- /* We have a valid label */
- return offset;
- }
-}
-
-/**
- * Decode RFC1035-encoded DNS name
- *
- * @v name DNS name
- * @v data Output buffer
- * @v len Length of output buffer
- * @ret len Length of decoded DNS name, or negative error
- */
-int dns_decode ( struct dns_name *name, char *data, size_t len ) {
- unsigned int recursion_limit = name->len; /* Generous upper bound */
- int offset = name->offset;
- const uint8_t *label;
- size_t decoded_len = 0;
- size_t label_len;
- size_t copy_len;
-
- while ( recursion_limit-- ) {
-
- /* Find valid DNS label */
- offset = dns_label ( name, offset );
- if ( offset < 0 )
- return offset;
-
- /* Terminate if we have reached the root */
- label = ( name->data + offset );
- label_len = *(label++);
- if ( label_len == 0 ) {
- if ( decoded_len < len )
- *data = '\0';
- return decoded_len;
- }
-
- /* Prepend '.' if applicable */
- if ( decoded_len && ( decoded_len++ < len ) )
- *(data++) = '.';
-
- /* Copy label to output buffer */
- copy_len = ( ( decoded_len < len ) ? ( len - decoded_len ) : 0);
- if ( copy_len > label_len )
- copy_len = label_len;
- memcpy ( data, label, copy_len );
- data += copy_len;
- decoded_len += label_len;
-
- /* Move to next label */
- offset += ( sizeof ( *label ) + label_len );
- }
-
- /* Recursion limit exceeded */
- return -EINVAL;
-}
-
-/**
- * Compare DNS names for equality
- *
- * @v first First DNS name
- * @v second Second DNS name
- * @ret rc Return status code
- */
-int dns_compare ( struct dns_name *first, struct dns_name *second ) {
- unsigned int recursion_limit = first->len; /* Generous upper bound */
- int first_offset = first->offset;
- int second_offset = second->offset;
- const uint8_t *first_label;
- const uint8_t *second_label;
- size_t label_len;
- size_t len;
-
- while ( recursion_limit-- ) {
-
- /* Find valid DNS labels */
- first_offset = dns_label ( first, first_offset );
- if ( first_offset < 0 )
- return first_offset;
- second_offset = dns_label ( second, second_offset );
- if ( second_offset < 0 )
- return second_offset;
-
- /* Compare label lengths */
- first_label = ( first->data + first_offset );
- second_label = ( second->data + second_offset );
- label_len = *(first_label++);
- if ( label_len != *(second_label++) )
- return -ENOENT;
- len = ( sizeof ( *first_label ) + label_len );
-
- /* Terminate if we have reached the root */
- if ( label_len == 0 )
- return 0;
-
- /* Compare label contents (case-insensitively) */
- while ( label_len-- ) {
- if ( tolower ( *(first_label++) ) !=
- tolower ( *(second_label++) ) )
- return -ENOENT;
- }
-
- /* Move to next labels */
- first_offset += len;
- second_offset += len;
- }
-
- /* Recursion limit exceeded */
- return -EINVAL;
-}
-
-/**
- * Copy a DNS name
- *
- * @v src Source DNS name
- * @v dst Destination DNS name
- * @ret len Length of copied DNS name, or negative error
- */
-int dns_copy ( struct dns_name *src, struct dns_name *dst ) {
- unsigned int recursion_limit = src->len; /* Generous upper bound */
- int src_offset = src->offset;
- size_t dst_offset = dst->offset;
- const uint8_t *label;
- size_t label_len;
- size_t copy_len;
- size_t len;
-
- while ( recursion_limit-- ) {
-
- /* Find valid DNS label */
- src_offset = dns_label ( src, src_offset );
- if ( src_offset < 0 )
- return src_offset;
-
- /* Copy as an uncompressed label */
- label = ( src->data + src_offset );
- label_len = *label;
- len = ( sizeof ( *label ) + label_len );
- copy_len = ( ( dst_offset < dst->len ) ?
- ( dst->len - dst_offset ) : 0 );
- if ( copy_len > len )
- copy_len = len;
- memcpy ( ( dst->data + dst_offset ), label, copy_len );
- src_offset += len;
- dst_offset += len;
-
- /* Terminate if we have reached the root */
- if ( label_len == 0 )
- return ( dst_offset - dst->offset );
- }
-
- /* Recursion limit exceeded */
- return -EINVAL;
-}
-
-/**
- * Skip RFC1035-encoded DNS name
- *
- * @v name DNS name
- * @ret offset Offset to next name, or negative error
- */
-int dns_skip ( struct dns_name *name ) {
- unsigned int recursion_limit = name->len; /* Generous upper bound */
- int offset = name->offset;
- int prev_offset;
- const uint8_t *label;
- size_t label_len;
-
- while ( recursion_limit-- ) {
-
- /* Find valid DNS label */
- prev_offset = offset;
- offset = dns_label ( name, prev_offset );
- if ( offset < 0 )
- return offset;
-
- /* Terminate if we have reached a compression pointer */
- if ( offset != prev_offset )
- return ( prev_offset + sizeof ( uint16_t ) );
-
- /* Skip this label */
- label = ( name->data + offset );
- label_len = *label;
- offset += ( sizeof ( *label ) + label_len );
-
- /* Terminate if we have reached the root */
- if ( label_len == 0 )
- return offset;
- }
-
- /* Recursion limit exceeded */
- return -EINVAL;
-}
-
-/**
- * Skip RFC1035-encoded DNS name in search list
- *
- * @v name DNS name
- * @ret offset Offset to next non-empty name, or negative error
- */
-static int dns_skip_search ( struct dns_name *name ) {
- int offset;
-
- /* Find next name */
- offset = dns_skip ( name );
- if ( offset < 0 )
- return offset;
-
- /* Skip over any subsequent empty names (e.g. due to padding
- * bytes used in the NDP DNSSL option).
- */
- while ( ( offset < ( ( int ) name->len ) ) &&
- ( *( ( uint8_t * ) ( name->data + offset ) ) == 0 ) ) {
- offset++;
- }
-
- return offset;
-}
-
-/**
- * Transcribe DNS name (for debugging)
- *
- * @v name DNS name
- * @ret string Transcribed DNS name
- */
-static const char * dns_name ( struct dns_name *name ) {
- static char buf[256];
- int len;
-
- len = dns_decode ( name, buf, sizeof ( buf ) );
- return ( ( len < 0 ) ? "<INVALID>" : buf );
-}
-
-/**
- * Name a DNS query type (for debugging)
- *
- * @v type Query type (in network byte order)
- * @ret name Type name
- */
-static const char * dns_type ( uint16_t type ) {
- switch ( type ) {
- case htons ( DNS_TYPE_A ): return "A";
- case htons ( DNS_TYPE_AAAA ): return "AAAA";
- case htons ( DNS_TYPE_CNAME ): return "CNAME";
- default: return "<UNKNOWN>";
- }
-}
-
-/** A DNS request */
-struct dns_request {
- /** Reference counter */
- struct refcnt refcnt;
- /** Name resolution interface */
- struct interface resolv;
- /** Data transfer interface */
- struct interface socket;
- /** Retry timer */
- struct retry_timer timer;
-
- /** Socket address to fill in with resolved address */
- union {
- struct sockaddr sa;
- struct sockaddr_in sin;
- struct sockaddr_in6 sin6;
- } address;
- /** Initial query type */
- uint16_t qtype;
- /** Buffer for current query */
- struct {
- /** Query header */
- struct dns_header query;
- /** Name buffer */
- char name[DNS_MAX_NAME_LEN];
- /** Space for question */
- struct dns_question padding;
- } __attribute__ (( packed )) buf;
- /** Current query name */
- struct dns_name name;
- /** Question within current query */
- struct dns_question *question;
- /** Length of current query */
- size_t len;
- /** Offset of search suffix within current query */
- size_t offset;
- /** Search list */
- struct dns_name search;
- /** Recursion counter */
- unsigned int recursion;
-};
-
-/**
- * Mark DNS request as complete
- *
- * @v dns DNS request
- * @v rc Return status code
- */
-static void dns_done ( struct dns_request *dns, int rc ) {
-
- /* Stop the retry timer */
- stop_timer ( &dns->timer );
-
- /* Shut down interfaces */
- intf_shutdown ( &dns->socket, rc );
- intf_shutdown ( &dns->resolv, rc );
-}
-
-/**
- * Mark DNS request as resolved and complete
- *
- * @v dns DNS request
- * @v rc Return status code
- */
-static void dns_resolved ( struct dns_request *dns ) {
-
- DBGC ( dns, "DNS %p found address %s\n",
- dns, sock_ntoa ( &dns->address.sa ) );
-
- /* Return resolved address */
- resolv_done ( &dns->resolv, &dns->address.sa );
-
- /* Mark operation as complete */
- dns_done ( dns, 0 );
-}
-
-/**
- * Construct DNS question
- *
- * @v dns DNS request
- * @ret rc Return status code
- */
-static int dns_question ( struct dns_request *dns ) {
- static struct dns_name search_root = {
- .data = "",
- .len = 1,
- };
- struct dns_name *search = &dns->search;
- int len;
- size_t offset;
-
- /* Use root suffix if search list is empty */
- if ( search->offset == search->len )
- search = &search_root;
-
- /* Overwrite current suffix */
- dns->name.offset = dns->offset;
- len = dns_copy ( search, &dns->name );
- if ( len < 0 )
- return len;
-
- /* Sanity check */
- offset = ( dns->name.offset + len );
- if ( offset > dns->name.len ) {
- DBGC ( dns, "DNS %p name is too long\n", dns );
- return -EINVAL;
- }
-
- /* Construct question */
- dns->question = ( ( ( void * ) &dns->buf ) + offset );
- dns->question->qtype = dns->qtype;
- dns->question->qclass = htons ( DNS_CLASS_IN );
-
- /* Store length */
- dns->len = ( offset + sizeof ( *(dns->question) ) );
-
- /* Restore name */
- dns->name.offset = offsetof ( typeof ( dns->buf ), name );
-
- DBGC2 ( dns, "DNS %p question is %s type %s\n", dns,
- dns_name ( &dns->name ), dns_type ( dns->question->qtype ) );
-
- return 0;
-}
-
-/**
- * Send DNS query
- *
- * @v dns DNS request
- * @ret rc Return status code
- */
-static int dns_send_packet ( struct dns_request *dns ) {
- struct dns_header *query = &dns->buf.query;
-
- /* Start retransmission timer */
- start_timer ( &dns->timer );
-
- /* Generate query identifier */
- query->id = random();
-
- /* Send query */
- DBGC ( dns, "DNS %p sending query ID %#04x for %s type %s\n", dns,
- ntohs ( query->id ), dns_name ( &dns->name ),
- dns_type ( dns->question->qtype ) );
-
- /* Send the data */
- return xfer_deliver_raw ( &dns->socket, query, dns->len );
-}
-
-/**
- * Handle DNS retransmission timer expiry
- *
- * @v timer Retry timer
- * @v fail Failure indicator
- */
-static void dns_timer_expired ( struct retry_timer *timer, int fail ) {
- struct dns_request *dns =
- container_of ( timer, struct dns_request, timer );
-
- if ( fail ) {
- dns_done ( dns, -ETIMEDOUT );
- } else {
- dns_send_packet ( dns );
- }
-}
-
-/**
- * Receive new data
- *
- * @v dns DNS request
- * @v iobuf I/O buffer
- * @v meta Data transfer metadata
- * @ret rc Return status code
- */
-static int dns_xfer_deliver ( struct dns_request *dns,
- struct io_buffer *iobuf,
- struct xfer_metadata *meta __unused ) {
- struct dns_header *response = iobuf->data;
- struct dns_header *query = &dns->buf.query;
- unsigned int qtype = dns->question->qtype;
- struct dns_name buf;
- union dns_rr *rr;
- int offset;
- size_t answer_offset;
- size_t next_offset;
- size_t rdlength;
- size_t name_len;
- int rc;
-
- /* Sanity check */
- if ( iob_len ( iobuf ) < sizeof ( *response ) ) {
- DBGC ( dns, "DNS %p received underlength packet length %zd\n",
- dns, iob_len ( iobuf ) );
- rc = -EINVAL;
- goto done;
- }
-
- /* Check response ID matches query ID */
- if ( response->id != query->id ) {
- DBGC ( dns, "DNS %p received unexpected response ID %#04x "
- "(wanted %d)\n", dns, ntohs ( response->id ),
- ntohs ( query->id ) );
- rc = -EINVAL;
- goto done;
- }
- DBGC ( dns, "DNS %p received response ID %#04x\n",
- dns, ntohs ( response->id ) );
-
- /* Check that we have exactly one question */
- if ( response->qdcount != htons ( 1 ) ) {
- DBGC ( dns, "DNS %p received response with %d questions\n",
- dns, ntohs ( response->qdcount ) );
- rc = -EINVAL;
- goto done;
- }
-
- /* Skip question section */
- buf.data = iobuf->data;
- buf.offset = sizeof ( *response );
- buf.len = iob_len ( iobuf );
- offset = dns_skip ( &buf );
- if ( offset < 0 ) {
- rc = offset;
- DBGC ( dns, "DNS %p received response with malformed "
- "question: %s\n", dns, strerror ( rc ) );
- goto done;
- }
- answer_offset = ( offset + sizeof ( struct dns_question ) );
-
- /* Search through response for useful answers. Do this
- * multiple times, to take advantage of useful nameservers
- * which send us e.g. the CNAME *and* the A record for the
- * pointed-to name.
- */
- for ( buf.offset = answer_offset ; buf.offset != buf.len ;
- buf.offset = next_offset ) {
-
- /* Check for valid name */
- offset = dns_skip ( &buf );
- if ( offset < 0 ) {
- rc = offset;
- DBGC ( dns, "DNS %p received response with malformed "
- "answer: %s\n", dns, strerror ( rc ) );
- goto done;
- }
-
- /* Check for sufficient space for resource record */
- rr = ( buf.data + offset );
- if ( ( offset + sizeof ( rr->common ) ) > buf.len ) {
- DBGC ( dns, "DNS %p received response with underlength "
- "RR\n", dns );
- rc = -EINVAL;
- goto done;
- }
- rdlength = ntohs ( rr->common.rdlength );
- next_offset = ( offset + sizeof ( rr->common ) + rdlength );
- if ( next_offset > buf.len ) {
- DBGC ( dns, "DNS %p received response with underlength "
- "RR\n", dns );
- rc = -EINVAL;
- goto done;
- }
-
- /* Skip non-matching names */
- if ( dns_compare ( &buf, &dns->name ) != 0 ) {
- DBGC2 ( dns, "DNS %p ignoring response for %s type "
- "%s\n", dns, dns_name ( &buf ),
- dns_type ( rr->common.type ) );
- continue;
- }
-
- /* Handle answer */
- switch ( rr->common.type ) {
-
- case htons ( DNS_TYPE_AAAA ):
-
- /* Found the target AAAA record */
- if ( rdlength < sizeof ( dns->address.sin6.sin6_addr )){
- DBGC ( dns, "DNS %p received response with "
- "underlength AAAA\n", dns );
- rc = -EINVAL;
- goto done;
- }
- dns->address.sin6.sin6_family = AF_INET6;
- memcpy ( &dns->address.sin6.sin6_addr,
- &rr->aaaa.in6_addr,
- sizeof ( dns->address.sin6.sin6_addr ) );
- dns_resolved ( dns );
- rc = 0;
- goto done;
-
- case htons ( DNS_TYPE_A ):
-
- /* Found the target A record */
- if ( rdlength < sizeof ( dns->address.sin.sin_addr ) ) {
- DBGC ( dns, "DNS %p received response with "
- "underlength A\n", dns );
- rc = -EINVAL;
- goto done;
- }
- dns->address.sin.sin_family = AF_INET;
- dns->address.sin.sin_addr = rr->a.in_addr;
- dns_resolved ( dns );
- rc = 0;
- goto done;
-
- case htons ( DNS_TYPE_CNAME ):
-
- /* Terminate the operation if we recurse too far */
- if ( ++dns->recursion > DNS_MAX_CNAME_RECURSION ) {
- DBGC ( dns, "DNS %p recursion exceeded\n",
- dns );
- rc = -ELOOP;
- dns_done ( dns, rc );
- goto done;
- }
-
- /* Found a CNAME record; update query and recurse */
- buf.offset = ( offset + sizeof ( rr->cname ) );
- DBGC ( dns, "DNS %p found CNAME %s\n",
- dns, dns_name ( &buf ) );
- dns->search.offset = dns->search.len;
- name_len = dns_copy ( &buf, &dns->name );
- dns->offset = ( offsetof ( typeof ( dns->buf ), name ) +
- name_len - 1 /* Strip root label */ );
- if ( ( rc = dns_question ( dns ) ) != 0 ) {
- dns_done ( dns, rc );
- goto done;
- }
- next_offset = answer_offset;
- break;
-
- default:
- DBGC ( dns, "DNS %p got unknown record type %d\n",
- dns, ntohs ( rr->common.type ) );
- break;
- }
- }
-
- /* Stop the retry timer. After this point, each code path
- * must either restart the timer by calling dns_send_packet(),
- * or mark the DNS operation as complete by calling
- * dns_done()
- */
- stop_timer ( &dns->timer );
-
- /* Determine what to do next based on the type of query we
- * issued and the response we received
- */
- switch ( qtype ) {
-
- case htons ( DNS_TYPE_AAAA ):
- /* We asked for an AAAA record and got nothing; try
- * the A.
- */
- DBGC ( dns, "DNS %p found no AAAA record; trying A\n", dns );
- dns->question->qtype = htons ( DNS_TYPE_A );
- dns_send_packet ( dns );
- rc = 0;
- goto done;
-
- case htons ( DNS_TYPE_A ):
- /* We asked for an A record and got nothing;
- * try the CNAME.
- */
- DBGC ( dns, "DNS %p found no A record; trying CNAME\n", dns );
- dns->question->qtype = htons ( DNS_TYPE_CNAME );
- dns_send_packet ( dns );
- rc = 0;
- goto done;
-
- case htons ( DNS_TYPE_CNAME ):
- /* We asked for a CNAME record. If we got a response
- * (i.e. if the next AAAA/A query is already set up),
- * then issue it.
- */
- if ( qtype == dns->qtype ) {
- dns_send_packet ( dns );
- rc = 0;
- goto done;
- }
-
- /* If we have already reached the end of the search list,
- * then terminate lookup.
- */
- if ( dns->search.offset == dns->search.len ) {
- DBGC ( dns, "DNS %p found no CNAME record\n", dns );
- rc = -ENXIO_NO_RECORD;
- dns_done ( dns, rc );
- goto done;
- }
-
- /* Move to next entry in search list. This can never fail,
- * since we have already used this entry.
- */
- DBGC ( dns, "DNS %p found no CNAME record; trying next "
- "suffix\n", dns );
- dns->search.offset = dns_skip_search ( &dns->search );
- if ( ( rc = dns_question ( dns ) ) != 0 ) {
- dns_done ( dns, rc );
- goto done;
- }
- dns_send_packet ( dns );
- goto done;
-
- default:
- assert ( 0 );
- rc = -EINVAL;
- dns_done ( dns, rc );
- goto done;
- }
-
- done:
- /* Free I/O buffer */
- free_iob ( iobuf );
- return rc;
-}
-
-/**
- * Receive new data
- *
- * @v dns DNS request
- * @v rc Reason for close
- */
-static void dns_xfer_close ( struct dns_request *dns, int rc ) {
-
- if ( ! rc )
- rc = -ECONNABORTED;
-
- dns_done ( dns, rc );
-}
-
-/** DNS socket interface operations */
-static struct interface_operation dns_socket_operations[] = {
- INTF_OP ( xfer_deliver, struct dns_request *, dns_xfer_deliver ),
- INTF_OP ( intf_close, struct dns_request *, dns_xfer_close ),
-};
-
-/** DNS socket interface descriptor */
-static struct interface_descriptor dns_socket_desc =
- INTF_DESC ( struct dns_request, socket, dns_socket_operations );
-
-/** DNS resolver interface operations */
-static struct interface_operation dns_resolv_op[] = {
- INTF_OP ( intf_close, struct dns_request *, dns_done ),
-};
-
-/** DNS resolver interface descriptor */
-static struct interface_descriptor dns_resolv_desc =
- INTF_DESC ( struct dns_request, resolv, dns_resolv_op );
-
-/**
- * Resolve name using DNS
- *
- * @v resolv Name resolution interface
- * @v name Name to resolve
- * @v sa Socket address to fill in
- * @ret rc Return status code
- */
-static int dns_resolv ( struct interface *resolv,
- const char *name, struct sockaddr *sa ) {
- struct dns_request *dns;
- struct dns_header *query;
- size_t search_len;
- int name_len;
- int rc;
-
- /* Fail immediately if no DNS servers */
- if ( ! nameserver.sa.sa_family ) {
- DBG ( "DNS not attempting to resolve \"%s\": "
- "no DNS servers\n", name );
- rc = -ENXIO_NO_NAMESERVER;
- goto err_no_nameserver;
- }
-
- /* Determine whether or not to use search list */
- search_len = ( strchr ( name, '.' ) ? 0 : dns_search.len );
-
- /* Allocate DNS structure */
- dns = zalloc ( sizeof ( *dns ) + search_len );
- if ( ! dns ) {
- rc = -ENOMEM;
- goto err_alloc_dns;
- }
- ref_init ( &dns->refcnt, NULL );
- intf_init ( &dns->resolv, &dns_resolv_desc, &dns->refcnt );
- intf_init ( &dns->socket, &dns_socket_desc, &dns->refcnt );
- timer_init ( &dns->timer, dns_timer_expired, &dns->refcnt );
- memcpy ( &dns->address.sa, sa, sizeof ( dns->address.sa ) );
- dns->search.data = ( ( ( void * ) dns ) + sizeof ( *dns ) );
- dns->search.len = search_len;
- memcpy ( dns->search.data, dns_search.data, search_len );
-
- /* Determine initial query type */
- switch ( nameserver.sa.sa_family ) {
- case AF_INET:
- dns->qtype = htons ( DNS_TYPE_A );
- break;
- case AF_INET6:
- dns->qtype = htons ( DNS_TYPE_AAAA );
- break;
- default:
- rc = -ENOTSUP;
- goto err_type;
- }
-
- /* Construct query */
- query = &dns->buf.query;
- query->flags = htons ( DNS_FLAG_RD );
- query->qdcount = htons ( 1 );
- dns->name.data = &dns->buf;
- dns->name.offset = offsetof ( typeof ( dns->buf ), name );
- dns->name.len = offsetof ( typeof ( dns->buf ), padding );
- name_len = dns_encode ( name, &dns->name );
- if ( name_len < 0 ) {
- rc = name_len;
- goto err_encode;
- }
- dns->offset = ( offsetof ( typeof ( dns->buf ), name ) +
- name_len - 1 /* Strip root label */ );
- if ( ( rc = dns_question ( dns ) ) != 0 )
- goto err_question;
-
- /* Open UDP connection */
- if ( ( rc = xfer_open_socket ( &dns->socket, SOCK_DGRAM,
- &nameserver.sa, NULL ) ) != 0 ) {
- DBGC ( dns, "DNS %p could not open socket: %s\n",
- dns, strerror ( rc ) );
- goto err_open_socket;
- }
-
- /* Start timer to trigger first packet */
- start_timer_nodelay ( &dns->timer );
-
- /* Attach parent interface, mortalise self, and return */
- intf_plug_plug ( &dns->resolv, resolv );
- ref_put ( &dns->refcnt );
- return 0;
-
- err_open_socket:
- err_question:
- err_encode:
- err_type:
- ref_put ( &dns->refcnt );
- err_alloc_dns:
- err_no_nameserver:
- return rc;
-}
-
-/** DNS name resolver */
-struct resolver dns_resolver __resolver ( RESOLV_NORMAL ) = {
- .name = "DNS",
- .resolv = dns_resolv,
-};
-
-/******************************************************************************
- *
- * Settings
- *
- ******************************************************************************
- */
-
-/**
- * Format DNS search list setting
- *
- * @v type Setting type
- * @v raw Raw setting value
- * @v raw_len Length of raw setting value
- * @v buf Buffer to contain formatted value
- * @v len Length of buffer
- * @ret len Length of formatted value, or negative error
- */
-static int format_dnssl_setting ( const struct setting_type *type __unused,
- const void *raw, size_t raw_len,
- char *buf, size_t len ) {
- struct dns_name name = {
- .data = ( ( void * ) raw ),
- .len = raw_len,
- };
- size_t remaining = len;
- size_t total = 0;
- int name_len;
-
- while ( name.offset < raw_len ) {
-
- /* Decode name */
- remaining = ( ( total < len ) ? ( len - total ) : 0 );
- name_len = dns_decode ( &name, ( buf + total ), remaining );
- if ( name_len < 0 )
- return name_len;
- total += name_len;
-
- /* Move to next name */
- name.offset = dns_skip_search ( &name );
-
- /* Add separator if applicable */
- if ( name.offset != raw_len ) {
- if ( total < len )
- buf[total] = ' ';
- total++;
- }
- }
-
- return total;
-}
-
-/** A DNS search list setting type */
-const struct setting_type setting_type_dnssl __setting_type = {
- .name = "dnssl",
- .format = format_dnssl_setting,
-};
-
-/** IPv4 DNS server setting */
-const struct setting dns_setting __setting ( SETTING_IP_EXTRA, dns ) = {
- .name = "dns",
- .description = "DNS server",
- .tag = DHCP_DNS_SERVERS,
- .type = &setting_type_ipv4,
-};
-
-/** IPv6 DNS server setting */
-const struct setting dns6_setting __setting ( SETTING_IP_EXTRA, dns6 ) = {
- .name = "dns6",
- .description = "DNS server",
- .tag = DHCPV6_DNS_SERVERS,
- .type = &setting_type_ipv6,
- .scope = &ipv6_scope,
-};
-
-/** DNS search list */
-const struct setting dnssl_setting __setting ( SETTING_IP_EXTRA, dnssl ) = {
- .name = "dnssl",
- .description = "DNS search list",
- .tag = DHCP_DOMAIN_SEARCH,
- .type = &setting_type_dnssl,
-};
-
-/**
- * Apply DNS search list
- *
- */
-static void apply_dns_search ( void ) {
- char *localdomain;
- int len;
-
- /* Free existing search list */
- free ( dns_search.data );
- memset ( &dns_search, 0, sizeof ( dns_search ) );
-
- /* Fetch DNS search list */
- len = fetch_setting_copy ( NULL, &dnssl_setting, NULL, NULL,
- &dns_search.data );
- if ( len >= 0 ) {
- dns_search.len = len;
- return;
- }
-
- /* If no DNS search list exists, try to fetch the local domain */
- fetch_string_setting_copy ( NULL, &domain_setting, &localdomain );
- if ( localdomain ) {
- len = dns_encode ( localdomain, &dns_search );
- if ( len >= 0 ) {
- dns_search.data = malloc ( len );
- if ( dns_search.data ) {
- dns_search.len = len;
- dns_encode ( localdomain, &dns_search );
- }
- }
- free ( localdomain );
- return;
- }
-}
-
-/**
- * Apply DNS settings
- *
- * @ret rc Return status code
- */
-static int apply_dns_settings ( void ) {
-
- /* Fetch DNS server address */
- nameserver.sa.sa_family = 0;
- if ( fetch_ipv6_setting ( NULL, &dns6_setting,
- &nameserver.sin6.sin6_addr ) >= 0 ) {
- nameserver.sin6.sin6_family = AF_INET6;
- } else if ( fetch_ipv4_setting ( NULL, &dns_setting,
- &nameserver.sin.sin_addr ) >= 0 ) {
- nameserver.sin.sin_family = AF_INET;
- }
- if ( nameserver.sa.sa_family ) {
- DBG ( "DNS using nameserver %s\n",
- sock_ntoa ( &nameserver.sa ) );
- }
-
- /* Fetch DNS search list */
- apply_dns_search();
- if ( DBG_LOG && ( dns_search.len != 0 ) ) {
- struct dns_name name;
- int offset;
-
- DBG ( "DNS search list:" );
- memcpy ( &name, &dns_search, sizeof ( name ) );
- while ( name.offset != name.len ) {
- DBG ( " %s", dns_name ( &name ) );
- offset = dns_skip_search ( &name );
- if ( offset < 0 )
- break;
- name.offset = offset;
- }
- DBG ( "\n" );
- }
-
- return 0;
-}
-
-/** DNS settings applicator */
-struct settings_applicator dns_applicator __settings_applicator = {
- .apply = apply_dns_settings,
-};