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m---------slirp0
-rw-r--r--slirp/src/dnssearch.c311
2 files changed, 0 insertions, 311 deletions
diff --git a/slirp b/slirp
new file mode 160000
+Subproject 59a1b1f165458c2acb7ff0525b543945f741622
diff --git a/slirp/src/dnssearch.c b/slirp/src/dnssearch.c
deleted file mode 100644
index 12c488971e..0000000000
--- a/slirp/src/dnssearch.c
+++ /dev/null
@@ -1,311 +0,0 @@
-/* SPDX-License-Identifier: MIT */
-/*
- * Domain search option for DHCP (RFC 3397)
- *
- * Copyright (c) 2012 Klaus Stengel
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#include "slirp.h"
-
-static const uint8_t RFC3397_OPT_DOMAIN_SEARCH = 119;
-static const uint8_t MAX_OPT_LEN = 255;
-static const uint8_t OPT_HEADER_LEN = 2;
-static const uint8_t REFERENCE_LEN = 2;
-
-struct compact_domain;
-
-typedef struct compact_domain {
- struct compact_domain *self;
- struct compact_domain *refdom;
- uint8_t *labels;
- size_t len;
- size_t common_octets;
-} CompactDomain;
-
-static size_t
-domain_suffix_diffoff(const CompactDomain *a, const CompactDomain *b)
-{
- size_t la = a->len, lb = b->len;
- uint8_t *da = a->labels + la, *db = b->labels + lb;
- size_t i, lm = (la < lb) ? la : lb;
-
- for (i = 0; i < lm; i++) {
- da--; db--;
- if (*da != *db) {
- break;
- }
- }
- return i;
-}
-
-static int domain_suffix_ord(const void *cva, const void *cvb)
-{
- const CompactDomain *a = cva, *b = cvb;
- size_t la = a->len, lb = b->len;
- size_t doff = domain_suffix_diffoff(a, b);
- uint8_t ca = a->labels[la - doff];
- uint8_t cb = b->labels[lb - doff];
-
- if (ca < cb) {
- return -1;
- }
- if (ca > cb) {
- return 1;
- }
- if (la < lb) {
- return -1;
- }
- if (la > lb) {
- return 1;
- }
- return 0;
-}
-
-static size_t domain_common_label(CompactDomain *a, CompactDomain *b)
-{
- size_t res, doff = domain_suffix_diffoff(a, b);
- uint8_t *first_eq_pos = a->labels + (a->len - doff);
- uint8_t *label = a->labels;
-
- while (*label && label < first_eq_pos) {
- label += *label + 1;
- }
- res = a->len - (label - a->labels);
- /* only report if it can help to reduce the packet size */
- return (res > REFERENCE_LEN) ? res : 0;
-}
-
-static void domain_fixup_order(CompactDomain *cd, size_t n)
-{
- size_t i;
-
- for (i = 0; i < n; i++) {
- CompactDomain *cur = cd + i, *next = cd[i].self;
-
- while (!cur->common_octets) {
- CompactDomain *tmp = next->self; /* backup target value */
-
- next->self = cur;
- cur->common_octets++;
-
- cur = next;
- next = tmp;
- }
- }
-}
-
-static void domain_mklabels(CompactDomain *cd, const char *input)
-{
- uint8_t *len_marker = cd->labels;
- uint8_t *output = len_marker; /* pre-incremented */
- const char *in = input;
- char cur_chr;
- size_t len = 0;
-
- if (cd->len == 0) {
- goto fail;
- }
- cd->len++;
-
- do {
- cur_chr = *in++;
- if (cur_chr == '.' || cur_chr == '\0') {
- len = output - len_marker;
- if ((len == 0 && cur_chr == '.') || len >= 64) {
- goto fail;
- }
- *len_marker = len;
-
- output++;
- len_marker = output;
- } else {
- output++;
- *output = cur_chr;
- }
- } while (cur_chr != '\0');
-
- /* ensure proper zero-termination */
- if (len != 0) {
- *len_marker = 0;
- cd->len++;
- }
- return;
-
-fail:
- g_warning("failed to parse domain name '%s'\n", input);
- cd->len = 0;
-}
-
-static void
-domain_mkxrefs(CompactDomain *doms, CompactDomain *last, size_t depth)
-{
- CompactDomain *i = doms, *target = doms;
-
- do {
- if (i->labels < target->labels) {
- target = i;
- }
- } while (i++ != last);
-
- for (i = doms; i != last; i++) {
- CompactDomain *group_last;
- size_t next_depth;
-
- if (i->common_octets == depth) {
- continue;
- }
-
- next_depth = -1;
- for (group_last = i; group_last != last; group_last++) {
- size_t co = group_last->common_octets;
- if (co <= depth) {
- break;
- }
- if (co < next_depth) {
- next_depth = co;
- }
- }
- domain_mkxrefs(i, group_last, next_depth);
-
- i = group_last;
- if (i == last) {
- break;
- }
- }
-
- if (depth == 0) {
- return;
- }
-
- i = doms;
- do {
- if (i != target && i->refdom == NULL) {
- i->refdom = target;
- i->common_octets = depth;
- }
- } while (i++ != last);
-}
-
-static size_t domain_compactify(CompactDomain *domains, size_t n)
-{
- uint8_t *start = domains->self->labels, *outptr = start;
- size_t i;
-
- for (i = 0; i < n; i++) {
- CompactDomain *cd = domains[i].self;
- CompactDomain *rd = cd->refdom;
-
- if (rd != NULL) {
- size_t moff = (rd->labels - start)
- + (rd->len - cd->common_octets);
- if (moff < 0x3FFFu) {
- cd->len -= cd->common_octets - 2;
- cd->labels[cd->len - 1] = moff & 0xFFu;
- cd->labels[cd->len - 2] = 0xC0u | (moff >> 8);
- }
- }
-
- if (cd->labels != outptr) {
- memmove(outptr, cd->labels, cd->len);
- cd->labels = outptr;
- }
- outptr += cd->len;
- }
- return outptr - start;
-}
-
-int translate_dnssearch(Slirp *s, const char **names)
-{
- size_t blocks, bsrc_start, bsrc_end, bdst_start;
- size_t i, num_domains, memreq = 0;
- uint8_t *result = NULL, *outptr;
- CompactDomain *domains = NULL;
- const char **nameptr = names;
-
- while (*nameptr != NULL) {
- nameptr++;
- }
-
- num_domains = nameptr - names;
- if (num_domains == 0) {
- return -2;
- }
-
- domains = g_malloc(num_domains * sizeof(*domains));
-
- for (i = 0; i < num_domains; i++) {
- size_t nlen = strlen(names[i]);
- memreq += nlen + 2; /* 1 zero octet + 1 label length octet */
- domains[i].self = domains + i;
- domains[i].len = nlen;
- domains[i].common_octets = 0;
- domains[i].refdom = NULL;
- }
-
- /* reserve extra 2 header bytes for each 255 bytes of output */
- memreq += DIV_ROUND_UP(memreq, MAX_OPT_LEN) * OPT_HEADER_LEN;
- result = g_malloc(memreq * sizeof(*result));
-
- outptr = result;
- for (i = 0; i < num_domains; i++) {
- domains[i].labels = outptr;
- domain_mklabels(domains + i, names[i]);
- outptr += domains[i].len;
- }
-
- if (outptr == result) {
- g_free(domains);
- g_free(result);
- return -1;
- }
-
- qsort(domains, num_domains, sizeof(*domains), domain_suffix_ord);
- domain_fixup_order(domains, num_domains);
-
- for (i = 1; i < num_domains; i++) {
- size_t cl = domain_common_label(domains + i - 1, domains + i);
- domains[i - 1].common_octets = cl;
- }
-
- domain_mkxrefs(domains, domains + num_domains - 1, 0);
- memreq = domain_compactify(domains, num_domains);
-
- blocks = DIV_ROUND_UP(memreq, MAX_OPT_LEN);
- bsrc_end = memreq;
- bsrc_start = (blocks - 1) * MAX_OPT_LEN;
- bdst_start = bsrc_start + blocks * OPT_HEADER_LEN;
- memreq += blocks * OPT_HEADER_LEN;
-
- while (blocks--) {
- size_t len = bsrc_end - bsrc_start;
- memmove(result + bdst_start, result + bsrc_start, len);
- result[bdst_start - 2] = RFC3397_OPT_DOMAIN_SEARCH;
- result[bdst_start - 1] = len;
- bsrc_end = bsrc_start;
- bsrc_start -= MAX_OPT_LEN;
- bdst_start -= MAX_OPT_LEN + OPT_HEADER_LEN;
- }
-
- g_free(domains);
- s->vdnssearch = result;
- s->vdnssearch_len = memreq;
- return 0;
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-28 11:52:14 +0000