diff options
Diffstat (limited to 'slirp/src/dnssearch.c')
| -rw-r--r-- | slirp/src/dnssearch.c | 311 |
1 files changed, 0 insertions, 311 deletions
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; -} |