Annotation of embedaddon/dhcp/minires/ns_parse.c, revision 1.1.1.1

1.1       misho       1: /*
                      2:  * Copyright (c) 2009-2010 by Internet Systems Consortium, Inc. ("ISC")
                      3:  * Copyright (c) 2004
                      4:  * Copyright (c) 1996-2003 by Internet Software Consortium
                      5:  *
                      6:  * Permission to use, copy, modify, and distribute this software for any
                      7:  * purpose with or without fee is hereby granted, provided that the above
                      8:  * copyright notice and this permission notice appear in all copies.
                      9:  *
                     10:  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
                     11:  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
                     12:  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
                     13:  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
                     14:  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
                     15:  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
                     16:  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
                     17:  *
                     18:  *   Internet Systems Consortium, Inc.
                     19:  *   950 Charter Street
                     20:  *   Redwood City, CA 94063
                     21:  *   <info@isc.org>
                     22:  *   https://www.isc.org/
                     23:  */
                     24: 
                     25: #ifndef lint
1.1.1.1 ! misho      26: static const char rcsid[] = "$Id: ns_parse.c,v 1.3.786.3 2010/07/27 21:23:34 sar Exp $";
1.1       misho      27: #endif
                     28: 
                     29: /* Import. */
                     30: 
                     31: #include <sys/types.h>
                     32: 
                     33: #include <netinet/in.h>
                     34: #include <sys/socket.h>
                     35: 
                     36: #include <errno.h>
                     37: #include <string.h>
                     38: 
                     39: #include "minires/minires.h"
                     40: #include "arpa/nameser.h"
                     41: 
                     42: /* Forward. */
                     43: 
                     44: static void    setsection(ns_msg *msg, ns_sect sect);
                     45: 
                     46: /* Macros. */
                     47: 
                     48: /* Public. */
                     49: 
                     50: /* These need to be in the same order as the nres.h:ns_flag enum. */
                     51: struct _ns_flagdata _ns_flagdata[16] = {
                     52:        { 0x8000, 15 },         /* qr. */
                     53:        { 0x7800, 11 },         /* opcode. */
                     54:        { 0x0400, 10 },         /* aa. */
                     55:        { 0x0200, 9 },          /* tc. */
                     56:        { 0x0100, 8 },          /* rd. */
                     57:        { 0x0080, 7 },          /* ra. */
                     58:        { 0x0040, 6 },          /* z. */
                     59:        { 0x0020, 5 },          /* ad. */
                     60:        { 0x0010, 4 },          /* cd. */
                     61:        { 0x000f, 0 },          /* rcode. */
                     62:        { 0x0000, 0 },          /* expansion (1/6). */
                     63:        { 0x0000, 0 },          /* expansion (2/6). */
                     64:        { 0x0000, 0 },          /* expansion (3/6). */
                     65:        { 0x0000, 0 },          /* expansion (4/6). */
                     66:        { 0x0000, 0 },          /* expansion (5/6). */
                     67:        { 0x0000, 0 },          /* expansion (6/6). */
                     68: };
                     69: 
                     70: isc_result_t
                     71: ns_skiprr(const u_char *ptr, const u_char *eom, ns_sect section, int count,
                     72:          int *rc) {
                     73:        const u_char *optr = ptr;
                     74: 
                     75:        for ((void)NULL; count > 0; count--) {
                     76:                int b, rdlength;
                     77: 
                     78:                b = dn_skipname(ptr, eom);
                     79:                if (b < 0)
                     80:                        return ISC_R_INCOMPLETE;
                     81:                ptr += b/*Name*/ + NS_INT16SZ/*Type*/ + NS_INT16SZ/*Class*/;
                     82:                if (section != ns_s_qd) {
                     83:                        if (ptr + NS_INT32SZ + NS_INT16SZ > eom)
                     84:                                return ISC_R_INCOMPLETE;
                     85:                        ptr += NS_INT32SZ/*TTL*/;
                     86:                        rdlength = getUShort(ptr);
                     87:                        ptr += 2;
                     88:                        ptr += rdlength/*RData*/;
                     89:                }
                     90:        }
                     91:        if (ptr > eom)
                     92:                return ISC_R_INCOMPLETE;
                     93:        if (rc)
                     94:                *rc = ptr - optr;
                     95:        return ISC_R_SUCCESS;
                     96: }
                     97: 
                     98: isc_result_t
                     99: ns_initparse(const u_char *msg, unsigned msglen, ns_msg *handle) {
                    100:        const u_char *eom = msg + msglen;
                    101:        int i;
                    102: 
                    103:        memset(handle, 0x5e, sizeof *handle);
                    104:        handle->_msg = msg;
                    105:        handle->_eom = eom;
                    106:        if (msg + NS_INT16SZ > eom)
                    107:                return ISC_R_INCOMPLETE;
                    108:        handle->_id = getUShort (msg);
                    109:        msg += 2;
                    110:        if (msg + NS_INT16SZ > eom)
                    111:                return ISC_R_INCOMPLETE;
                    112:        handle->_flags = getUShort (msg);
                    113:        msg += 2;
                    114:        for (i = 0; i < ns_s_max; i++) {
                    115:                if (msg + NS_INT16SZ > eom)
                    116:                        return ISC_R_INCOMPLETE;
                    117:                handle->_counts[i] = getUShort (msg);
                    118:                msg += 2;
                    119:        }
                    120:        for (i = 0; i < ns_s_max; i++)
                    121:                if (handle->_counts[i] == 0)
                    122:                        handle->_sections[i] = NULL;
                    123:                else {
                    124:                        int b;
                    125:                        isc_result_t status =
                    126:                                ns_skiprr(msg, eom, (ns_sect)i,
                    127:                                          handle->_counts[i], &b);
                    128: 
                    129:                        if (status != ISC_R_SUCCESS)
                    130:                                return status;
                    131:                        handle->_sections[i] = msg;
                    132:                        msg += b;
                    133:                }
                    134:        if (msg != eom)
                    135:                return ISC_R_INCOMPLETE;
                    136:        setsection(handle, ns_s_max);
                    137:        return ISC_R_SUCCESS;
                    138: }
                    139: 
                    140: isc_result_t
                    141: ns_parserr(ns_msg *handle, ns_sect section, int rrnum, ns_rr *rr) {
                    142:        int b;
                    143:        isc_result_t status;
                    144: 
                    145:        /* Make section right. */
                    146:        if (section < 0 || section >= ns_s_max)
                    147:                return ISC_R_NOTIMPLEMENTED;
                    148:        if (section != handle->_sect)
                    149:                setsection(handle, section);
                    150: 
                    151:        /* Make rrnum right. */
                    152:        if (rrnum == -1)
                    153:                rrnum = handle->_rrnum;
                    154:        if (rrnum < 0 || rrnum >= handle->_counts[(int)section])
                    155:                return ISC_R_UNKNOWNATTRIBUTE;
                    156:        if (rrnum < handle->_rrnum)
                    157:                setsection(handle, section);
                    158:        if (rrnum > handle->_rrnum) {
                    159:                status = ns_skiprr(handle->_ptr, handle->_eom, section,
                    160:                              rrnum - handle->_rrnum, &b);
                    161: 
                    162:                if (status != ISC_R_SUCCESS)
                    163:                        return status;
                    164:                handle->_ptr += b;
                    165:                handle->_rrnum = rrnum;
                    166:        }
                    167: 
                    168:        /* Do the parse. */
                    169:        b = dn_expand(handle->_msg, handle->_eom,
                    170:                      handle->_ptr, rr->name, NS_MAXDNAME);
                    171:        if (b < 0)
                    172:                return ISC_R_FORMERR;
                    173:        handle->_ptr += b;
                    174:        if (handle->_ptr + NS_INT16SZ + NS_INT16SZ > handle->_eom)
                    175:                return ISC_R_INCOMPLETE;
                    176:        rr->type = getUShort (handle->_ptr);
                    177:        handle -> _ptr += 2;
                    178:        rr->rr_class = getUShort (handle->_ptr);
                    179:        handle -> _ptr += 2;
                    180:        if (section == ns_s_qd) {
                    181:                rr->ttl = 0;
                    182:                rr->rdlength = 0;
                    183:                rr->rdata = NULL;
                    184:        } else {
                    185:                if (handle->_ptr + NS_INT32SZ + NS_INT16SZ > handle->_eom)
                    186:                        return ISC_R_INCOMPLETE;
                    187:                rr->ttl = getULong (handle->_ptr);
                    188:                handle -> _ptr += 4;
                    189:                rr->rdlength = getUShort (handle->_ptr);
                    190:                handle -> _ptr += 2;
                    191:                if (handle->_ptr + rr->rdlength > handle->_eom)
                    192:                        return ISC_R_INCOMPLETE;
                    193:                rr->rdata = handle->_ptr;
                    194:                handle->_ptr += rr->rdlength;
                    195:        }
                    196:        if (++handle->_rrnum > handle->_counts[(int)section])
                    197:                setsection(handle, (ns_sect)((int)section + 1));
                    198: 
                    199:        /* All done. */
                    200:        return ISC_R_SUCCESS;
                    201: }
                    202: 
                    203: /* Private. */
                    204: 
                    205: static void
                    206: setsection(ns_msg *msg, ns_sect sect) {
                    207:        msg->_sect = sect;
                    208:        if (sect == ns_s_max) {
                    209:                msg->_rrnum = -1;
                    210:                msg->_ptr = NULL;
                    211:        } else {
                    212:                msg->_rrnum = 0;
                    213:                msg->_ptr = msg->_sections[(int)sect];
                    214:        }
                    215: }

FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>