diff options
Diffstat (limited to 'REORG.TODO/resolv/nss_dns/dns-network.c')
| -rw-r--r-- | REORG.TODO/resolv/nss_dns/dns-network.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/REORG.TODO/resolv/nss_dns/dns-network.c b/REORG.TODO/resolv/nss_dns/dns-network.c new file mode 100644 index 0000000000..2be72d33a3 --- /dev/null +++ b/REORG.TODO/resolv/nss_dns/dns-network.c @@ -0,0 +1,472 @@ +/* Copyright (C) 1996-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +/* Parts of this file are plain copies of the file `getnetnamadr.c' from + the bind package and it has the following copyright. */ + +/* Copyright (c) 1993 Carlos Leandro and Rui Salgueiro + * Dep. Matematica Universidade de Coimbra, Portugal, Europe + * + * Permission to use, copy, modify, and 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. + */ +/* + * Copyright (c) 1983, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <ctype.h> +#include <errno.h> +#include <netdb.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stdint.h> +#include <stddef.h> + +#include "nsswitch.h" +#include <arpa/inet.h> +#include <arpa/nameser.h> + +/* Maximum number of aliases we allow. */ +#define MAX_NR_ALIASES 48 + + +#if PACKETSZ > 65536 +# define MAXPACKET PACKETSZ +#else +# define MAXPACKET 65536 +#endif + + +typedef enum +{ + BYADDR, + BYNAME +} lookup_method; + + +/* We need this time later. */ +typedef union querybuf +{ + HEADER hdr; + u_char buf[MAXPACKET]; +} querybuf; + +/* Prototypes for local functions. */ +static enum nss_status getanswer_r (const querybuf *answer, int anslen, + struct netent *result, char *buffer, + size_t buflen, int *errnop, int *h_errnop, + lookup_method net_i); + + +enum nss_status +_nss_dns_getnetbyname_r (const char *name, struct netent *result, + char *buffer, size_t buflen, int *errnop, + int *herrnop) +{ + /* Return entry for network with NAME. */ + union + { + querybuf *buf; + u_char *ptr; + } net_buffer; + querybuf *orig_net_buffer; + int anslen; + enum nss_status status; + + if (__res_maybe_init (&_res, 0) == -1) + return NSS_STATUS_UNAVAIL; + + net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024); + + anslen = __libc_res_nsearch (&_res, name, C_IN, T_PTR, net_buffer.buf->buf, + 1024, &net_buffer.ptr, NULL, NULL, NULL, NULL); + if (anslen < 0) + { + /* Nothing found. */ + *errnop = errno; + if (net_buffer.buf != orig_net_buffer) + free (net_buffer.buf); + return (errno == ECONNREFUSED + || errno == EPFNOSUPPORT + || errno == EAFNOSUPPORT) + ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; + } + + status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + errnop, herrnop, BYNAME); + if (net_buffer.buf != orig_net_buffer) + free (net_buffer.buf); + return status; +} + + +enum nss_status +_nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result, + char *buffer, size_t buflen, int *errnop, + int *herrnop) +{ + /* Return entry for network with NAME. */ + enum nss_status status; + union + { + querybuf *buf; + u_char *ptr; + } net_buffer; + querybuf *orig_net_buffer; + unsigned int net_bytes[4]; + char qbuf[MAXDNAME]; + int cnt, anslen; + u_int32_t net2; + int olderr = errno; + + /* No net address lookup for IPv6 yet. */ + if (type != AF_INET) + return NSS_STATUS_UNAVAIL; + + if (__res_maybe_init (&_res, 0) == -1) + return NSS_STATUS_UNAVAIL; + + net2 = (u_int32_t) net; + for (cnt = 4; net2 != 0; net2 >>= 8) + net_bytes[--cnt] = net2 & 0xff; + + switch (cnt) + { + case 3: + /* Class A network. */ + sprintf (qbuf, "0.0.0.%u.in-addr.arpa", net_bytes[3]); + break; + case 2: + /* Class B network. */ + sprintf (qbuf, "0.0.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2]); + break; + case 1: + /* Class C network. */ + sprintf (qbuf, "0.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2], + net_bytes[1]); + break; + case 0: + /* Class D - E network. */ + sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2], + net_bytes[1], net_bytes[0]); + break; + } + + net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024); + + anslen = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf, + 1024, &net_buffer.ptr, NULL, NULL, NULL, NULL); + if (anslen < 0) + { + /* Nothing found. */ + int err = errno; + __set_errno (olderr); + if (net_buffer.buf != orig_net_buffer) + free (net_buffer.buf); + return (err == ECONNREFUSED + || err == EPFNOSUPPORT + || err == EAFNOSUPPORT) + ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND; + } + + status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen, + errnop, herrnop, BYADDR); + if (net_buffer.buf != orig_net_buffer) + free (net_buffer.buf); + if (status == NSS_STATUS_SUCCESS) + { + /* Strip trailing zeros. */ + unsigned int u_net = net; /* Maybe net should be unsigned? */ + + while ((u_net & 0xff) == 0 && u_net != 0) + u_net >>= 8; + result->n_net = u_net; + } + + return status; +} + + +static enum nss_status +getanswer_r (const querybuf *answer, int anslen, struct netent *result, + char *buffer, size_t buflen, int *errnop, int *h_errnop, + lookup_method net_i) +{ + /* + * Find first satisfactory answer + * + * answer --> +------------+ ( MESSAGE ) + * | Header | + * +------------+ + * | Question | the question for the name server + * +------------+ + * | Answer | RRs answering the question + * +------------+ + * | Authority | RRs pointing toward an authority + * | Additional | RRs holding additional information + * +------------+ + */ + struct net_data + { + char *aliases[MAX_NR_ALIASES]; + char linebuffer[0]; + } *net_data; + + uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct net_data); + buffer += pad; + + if (__glibc_unlikely (buflen < sizeof (*net_data) + pad)) + { + /* The buffer is too small. */ + too_small: + *errnop = ERANGE; + *h_errnop = NETDB_INTERNAL; + return NSS_STATUS_TRYAGAIN; + } + buflen -= pad; + + net_data = (struct net_data *) buffer; + int linebuflen = buflen - offsetof (struct net_data, linebuffer); + if (buflen - offsetof (struct net_data, linebuffer) != linebuflen) + linebuflen = INT_MAX; + const unsigned char *end_of_message = &answer->buf[anslen]; + const HEADER *header_pointer = &answer->hdr; + /* #/records in the answer section. */ + int answer_count = ntohs (header_pointer->ancount); + /* #/entries in the question section. */ + int question_count = ntohs (header_pointer->qdcount); + char *bp = net_data->linebuffer; + const unsigned char *cp = &answer->buf[HFIXEDSZ]; + char **alias_pointer; + int have_answer; + u_char packtmp[NS_MAXCDNAME]; + + if (question_count == 0) + { + /* FIXME: the Sun version uses for host name lookup an additional + parameter for pointing to h_errno. this is missing here. + OSF/1 has a per-thread h_errno variable. */ + if (header_pointer->aa != 0) + { + __set_h_errno (HOST_NOT_FOUND); + return NSS_STATUS_NOTFOUND; + } + else + { + __set_h_errno (TRY_AGAIN); + return NSS_STATUS_TRYAGAIN; + } + } + + /* Skip the question part. */ + while (question_count-- > 0) + { + int n = __dn_skipname (cp, end_of_message); + if (n < 0 || end_of_message - (cp + n) < QFIXEDSZ) + { + __set_h_errno (NO_RECOVERY); + return NSS_STATUS_UNAVAIL; + } + cp += n + QFIXEDSZ; + } + + alias_pointer = result->n_aliases = &net_data->aliases[0]; + *alias_pointer = NULL; + have_answer = 0; + + while (--answer_count >= 0 && cp < end_of_message) + { + int n = __ns_name_unpack (answer->buf, end_of_message, cp, + packtmp, sizeof packtmp); + if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) + { + if (errno == EMSGSIZE) + goto too_small; + + n = -1; + } + + if (n > 0 && bp[0] == '.') + bp[0] = '\0'; + + if (n < 0 || res_dnok (bp) == 0) + break; + cp += n; + + if (end_of_message - cp < 10) + { + __set_h_errno (NO_RECOVERY); + return NSS_STATUS_UNAVAIL; + } + + int type, class; + GETSHORT (type, cp); + GETSHORT (class, cp); + cp += INT32SZ; /* TTL */ + uint16_t rdatalen; + GETSHORT (rdatalen, cp); + if (end_of_message - cp < rdatalen) + { + __set_h_errno (NO_RECOVERY); + return NSS_STATUS_UNAVAIL; + } + + if (class == C_IN && type == T_PTR) + { + n = __ns_name_unpack (answer->buf, end_of_message, cp, + packtmp, sizeof packtmp); + if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1) + { + if (errno == EMSGSIZE) + goto too_small; + + n = -1; + } + + if (n < 0 || !res_hnok (bp)) + { + /* XXX What does this mean? The original form from bind + returns NULL. Incrementing cp has no effect in any case. + What should I return here. ??? */ + cp += n; + return NSS_STATUS_UNAVAIL; + } + cp += rdatalen; + if (alias_pointer + 2 < &net_data->aliases[MAX_NR_ALIASES]) + { + *alias_pointer++ = bp; + n = strlen (bp) + 1; + bp += n; + linebuflen -= n; + result->n_addrtype = class == C_IN ? AF_INET : AF_UNSPEC; + ++have_answer; + } + } + else + /* Skip over unknown record data. */ + cp += rdatalen; + } + + if (have_answer) + { + *alias_pointer = NULL; + switch (net_i) + { + case BYADDR: + result->n_name = *result->n_aliases++; + result->n_net = 0L; + return NSS_STATUS_SUCCESS; + + case BYNAME: + { + char **ap; + for (ap = result->n_aliases; *ap != NULL; ++ap) + { + /* Check each alias name for being of the forms: + 4.3.2.1.in-addr.arpa = net 1.2.3.4 + 3.2.1.in-addr.arpa = net 0.1.2.3 + 2.1.in-addr.arpa = net 0.0.1.2 + 1.in-addr.arpa = net 0.0.0.1 + */ + uint32_t val = 0; /* Accumulator for n_net value. */ + unsigned int shift = 0; /* Which part we are parsing now. */ + const char *p = *ap; /* Consuming the string. */ + do + { + /* Match the leading 0 or 0[xX] base indicator. */ + unsigned int base = 10; + if (*p == '0' && p[1] != '.') + { + base = 8; + ++p; + if (*p == 'x' || *p == 'X') + { + base = 16; + ++p; + if (*p == '.') + break; /* No digit here. Give up on alias. */ + } + if (*p == '\0') + break; + } + + uint32_t part = 0; /* Accumulates this part's number. */ + do + { + if (isdigit (*p) && (*p - '0' < base)) + part = (part * base) + (*p - '0'); + else if (base == 16 && isxdigit (*p)) + part = (part << 4) + 10 + (tolower (*p) - 'a'); + ++p; + } while (*p != '\0' && *p != '.'); + + if (*p != '.') + break; /* Bad form. Give up on this name. */ + + /* Install this as the next more significant byte. */ + val |= part << shift; + shift += 8; + ++p; + + /* If we are out of digits now, there are two cases: + 1. We are done with digits and now see "in-addr.arpa". + 2. This is not the droid we are looking for. */ + if (!isdigit (*p) && !strcasecmp (p, "in-addr.arpa")) + { + result->n_net = val; + return NSS_STATUS_SUCCESS; + } + + /* Keep going when we have seen fewer than 4 parts. */ + } while (shift < 32); + } + } + break; + } + } + + __set_h_errno (TRY_AGAIN); + return NSS_STATUS_TRYAGAIN; +} |