2018-09-06 15:16:02 +08:00
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/***************************************************************************
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* _ _ ____ _
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* Project ___| | | | _ \| |
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* / __| | | | |_) | |
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* | (__| |_| | _ <| |___
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* \___|\___/|_| \_\_____|
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*
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2018-09-17 04:04:49 +08:00
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* Copyright (C) 2018 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
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2018-09-06 15:16:02 +08:00
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*
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* This software is licensed as described in the file COPYING, which
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* you should have received as part of this distribution. The terms
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* are also available at https://curl.haxx.se/docs/copyright.html.
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*
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* You may opt to use, copy, modify, merge, publish, distribute and/or sell
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* copies of the Software, and permit persons to whom the Software is
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* furnished to do so, under the terms of the COPYING file.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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***************************************************************************/
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#include "curl_setup.h"
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2018-09-29 20:08:29 +08:00
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2018-09-06 15:16:02 +08:00
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#include "urldata.h"
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#include "curl_addrinfo.h"
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2018-09-29 20:08:29 +08:00
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#include "doh.h"
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2018-09-06 15:16:02 +08:00
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#include "sendf.h"
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#include "multiif.h"
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#include "url.h"
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#include "share.h"
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#include "curl_base64.h"
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#include "connect.h"
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2018-12-05 22:21:27 +08:00
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#include "strdup.h"
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2018-09-06 15:16:02 +08:00
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/* The last 3 #include files should be in this order */
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#include "curl_printf.h"
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#include "curl_memory.h"
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#include "memdebug.h"
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#define DNS_CLASS_IN 0x01
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#define DOH_MAX_RESPONSE_SIZE 3000 /* bytes */
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2018-10-17 05:35:44 +08:00
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#ifndef CURL_DISABLE_VERBOSE_STRINGS
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2018-09-06 15:16:02 +08:00
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static const char * const errors[]={
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"",
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"Bad label",
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"Out of range",
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"Label loop",
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"Too small",
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"Out of memory",
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"RDATA length",
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"Malformat",
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"Bad RCODE",
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"Unexpected TYPE",
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"Unexpected CLASS",
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"No content",
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"Bad ID"
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};
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static const char *doh_strerror(DOHcode code)
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{
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if((code >= DOH_OK) && (code <= DOH_DNS_BAD_ID))
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return errors[code];
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return "bad error code";
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}
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2018-10-17 05:35:44 +08:00
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#endif
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2018-09-06 15:16:02 +08:00
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2018-06-19 22:08:05 +08:00
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#ifdef DEBUGBUILD
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#define UNITTEST
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#else
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#define UNITTEST static
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#endif
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UNITTEST DOHcode doh_encode(const char *host,
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DNStype dnstype,
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unsigned char *dnsp, /* buffer */
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size_t len, /* buffer size */
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size_t *olen) /* output length */
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2018-09-06 15:16:02 +08:00
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{
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size_t hostlen = strlen(host);
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unsigned char *orig = dnsp;
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const char *hostp = host;
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if(len < (12 + hostlen + 4))
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return DOH_TOO_SMALL_BUFFER;
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*dnsp++ = 0; /* 16 bit id */
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*dnsp++ = 0;
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*dnsp++ = 0x01; /* |QR| Opcode |AA|TC|RD| Set the RD bit */
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*dnsp++ = '\0'; /* |RA| Z | RCODE | */
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*dnsp++ = '\0';
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*dnsp++ = 1; /* QDCOUNT (number of entries in the question section) */
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*dnsp++ = '\0';
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*dnsp++ = '\0'; /* ANCOUNT */
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*dnsp++ = '\0';
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*dnsp++ = '\0'; /* NSCOUNT */
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*dnsp++ = '\0';
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*dnsp++ = '\0'; /* ARCOUNT */
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/* store a QNAME */
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do {
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char *dot = strchr(hostp, '.');
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size_t labellen;
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bool found = false;
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if(dot) {
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found = true;
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labellen = dot - hostp;
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}
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else
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labellen = strlen(hostp);
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2018-06-19 22:08:05 +08:00
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if(labellen > 63) {
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2018-09-06 15:16:02 +08:00
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/* too long label, error out */
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2018-06-19 22:08:05 +08:00
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*olen = 0;
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2018-09-06 15:16:02 +08:00
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return DOH_DNS_BAD_LABEL;
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2018-06-19 22:08:05 +08:00
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}
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2018-09-06 15:16:02 +08:00
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*dnsp++ = (unsigned char)labellen;
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memcpy(dnsp, hostp, labellen);
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dnsp += labellen;
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hostp += labellen + 1;
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if(!found) {
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*dnsp++ = 0; /* terminating zero */
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break;
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}
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} while(1);
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*dnsp++ = '\0'; /* upper 8 bit TYPE */
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*dnsp++ = (unsigned char)dnstype;
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*dnsp++ = '\0'; /* upper 8 bit CLASS */
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*dnsp++ = DNS_CLASS_IN; /* IN - "the Internet" */
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*olen = dnsp - orig;
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return DOH_OK;
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}
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static size_t
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doh_write_cb(void *contents, size_t size, size_t nmemb, void *userp)
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{
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size_t realsize = size * nmemb;
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struct dohresponse *mem = (struct dohresponse *)userp;
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if((mem->size + realsize) > DOH_MAX_RESPONSE_SIZE)
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/* suspiciously much for us */
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return 0;
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2018-12-05 22:21:27 +08:00
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mem->memory = Curl_saferealloc(mem->memory, mem->size + realsize);
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if(!mem->memory)
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2018-09-06 15:16:02 +08:00
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/* out of memory! */
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return 0;
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memcpy(&(mem->memory[mem->size]), contents, realsize);
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mem->size += realsize;
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return realsize;
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}
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/* called from multi.c when this DOH transfer is complete */
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static int Curl_doh_done(struct Curl_easy *doh, CURLcode result)
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{
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struct Curl_easy *data = doh->set.dohfor;
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/* so one of the DOH request done for the 'data' transfer is now complete! */
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data->req.doh.pending--;
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2018-09-17 04:04:49 +08:00
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infof(data, "a DOH request is completed, %u to go\n", data->req.doh.pending);
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2018-09-06 15:16:02 +08:00
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if(result)
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infof(data, "DOH request %s\n", curl_easy_strerror(result));
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if(!data->req.doh.pending) {
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/* DOH completed */
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curl_slist_free_all(data->req.doh.headers);
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data->req.doh.headers = NULL;
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Curl_expire(data, 0, EXPIRE_RUN_NOW);
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}
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return 0;
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}
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#define ERROR_CHECK_SETOPT(x,y) result = curl_easy_setopt(doh, x, y); \
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if(result) goto error
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static CURLcode dohprobe(struct Curl_easy *data,
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struct dnsprobe *p, DNStype dnstype,
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const char *host,
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const char *url, CURLM *multi,
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struct curl_slist *headers)
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{
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struct Curl_easy *doh = NULL;
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char *nurl = NULL;
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CURLcode result = CURLE_OK;
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timediff_t timeout_ms;
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DOHcode d = doh_encode(host, dnstype, p->dohbuffer, sizeof(p->dohbuffer),
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&p->dohlen);
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if(d) {
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failf(data, "Failed to encode DOH packet [%d]\n", d);
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return CURLE_OUT_OF_MEMORY;
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}
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p->dnstype = dnstype;
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p->serverdoh.memory = NULL;
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/* the memory will be grown as needed by realloc in the doh_write_cb
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function */
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p->serverdoh.size = 0;
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/* Note: this is code for sending the DoH request with GET but there's still
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no logic that actually enables this. We should either add that ability or
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yank out the GET code. Discuss! */
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if(data->set.doh_get) {
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char *b64;
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size_t b64len;
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result = Curl_base64url_encode(data, (char *)p->dohbuffer, p->dohlen,
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&b64, &b64len);
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if(result)
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goto error;
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nurl = aprintf("%s?dns=%s", url, b64);
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free(b64);
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if(!nurl) {
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result = CURLE_OUT_OF_MEMORY;
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goto error;
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}
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url = nurl;
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}
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timeout_ms = Curl_timeleft(data, NULL, TRUE);
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/* Curl_open() is the internal version of curl_easy_init() */
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result = Curl_open(&doh);
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if(!result) {
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2018-09-07 15:26:08 +08:00
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/* pass in the struct pointer via a local variable to please coverity and
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the gcc typecheck helpers */
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struct dohresponse *resp = &p->serverdoh;
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2018-09-06 15:16:02 +08:00
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ERROR_CHECK_SETOPT(CURLOPT_URL, url);
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ERROR_CHECK_SETOPT(CURLOPT_WRITEFUNCTION, doh_write_cb);
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2018-09-07 15:26:08 +08:00
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ERROR_CHECK_SETOPT(CURLOPT_WRITEDATA, resp);
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2018-09-06 15:16:02 +08:00
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if(!data->set.doh_get) {
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2018-09-07 15:26:08 +08:00
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ERROR_CHECK_SETOPT(CURLOPT_POSTFIELDS, p->dohbuffer);
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2018-10-02 17:15:29 +08:00
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ERROR_CHECK_SETOPT(CURLOPT_POSTFIELDSIZE, (long)p->dohlen);
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2018-09-06 15:16:02 +08:00
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}
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ERROR_CHECK_SETOPT(CURLOPT_HTTPHEADER, headers);
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2018-12-03 18:51:52 +08:00
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#ifdef USE_NGHTTP2
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2018-09-06 15:16:02 +08:00
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ERROR_CHECK_SETOPT(CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2TLS);
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2018-12-03 18:51:52 +08:00
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#endif
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2018-09-06 15:16:02 +08:00
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#ifndef CURLDEBUG
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/* enforce HTTPS if not debug */
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ERROR_CHECK_SETOPT(CURLOPT_PROTOCOLS, CURLPROTO_HTTPS);
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#endif
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ERROR_CHECK_SETOPT(CURLOPT_TIMEOUT_MS, (long)timeout_ms);
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ERROR_CHECK_SETOPT(CURLOPT_VERBOSE, 1L);
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doh->set.fmultidone = Curl_doh_done;
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doh->set.dohfor = data; /* identify for which transfer this is done */
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p->easy = doh;
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/* add this transfer to the multi handle */
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if(curl_multi_add_handle(multi, doh))
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goto error;
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}
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else
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goto error;
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free(nurl);
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return CURLE_OK;
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error:
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free(nurl);
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Curl_close(doh);
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return result;
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}
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/*
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* Curl_doh() resolves a name using DOH. It resolves a name and returns a
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* 'Curl_addrinfo *' with the address information.
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*/
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Curl_addrinfo *Curl_doh(struct connectdata *conn,
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const char *hostname,
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int port,
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int *waitp)
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{
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struct Curl_easy *data = conn->data;
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CURLcode result = CURLE_OK;
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*waitp = TRUE; /* this never returns synchronously */
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(void)conn;
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(void)hostname;
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(void)port;
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/* start clean, consider allocating this struct on demand */
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memset(&data->req.doh, 0, sizeof(struct dohdata));
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data->req.doh.host = hostname;
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data->req.doh.port = port;
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data->req.doh.headers =
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curl_slist_append(NULL,
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"Content-Type: application/dns-message");
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if(!data->req.doh.headers)
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goto error;
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if(conn->ip_version != CURL_IPRESOLVE_V6) {
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/* create IPv4 DOH request */
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result = dohprobe(data, &data->req.doh.probe[0], DNS_TYPE_A,
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hostname, data->set.str[STRING_DOH],
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data->multi, data->req.doh.headers);
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if(result)
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goto error;
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data->req.doh.pending++;
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}
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if(conn->ip_version != CURL_IPRESOLVE_V4) {
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/* create IPv6 DOH request */
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result = dohprobe(data, &data->req.doh.probe[1], DNS_TYPE_AAAA,
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hostname, data->set.str[STRING_DOH],
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data->multi, data->req.doh.headers);
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if(result)
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goto error;
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data->req.doh.pending++;
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}
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return NULL;
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error:
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curl_slist_free_all(data->req.doh.headers);
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data->req.doh.headers = NULL;
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curl_easy_cleanup(data->req.doh.probe[0].easy);
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data->req.doh.probe[0].easy = NULL;
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curl_easy_cleanup(data->req.doh.probe[1].easy);
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data->req.doh.probe[1].easy = NULL;
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return NULL;
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}
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|
static DOHcode skipqname(unsigned char *doh, size_t dohlen,
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|
unsigned int *indexp)
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|
|
{
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|
unsigned char length;
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do {
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if(dohlen < (*indexp + 1))
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return DOH_DNS_OUT_OF_RANGE;
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length = doh[*indexp];
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if((length & 0xc0) == 0xc0) {
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/* name pointer, advance over it and be done */
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if(dohlen < (*indexp + 2))
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return DOH_DNS_OUT_OF_RANGE;
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*indexp += 2;
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break;
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}
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if(length & 0xc0)
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return DOH_DNS_BAD_LABEL;
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|
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|
if(dohlen < (*indexp + 1 + length))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
*indexp += 1 + length;
|
|
|
|
} while(length);
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static unsigned short get16bit(unsigned char *doh, int index)
|
|
|
|
{
|
|
|
|
return (unsigned short)((doh[index] << 8) | doh[index + 1]);
|
|
|
|
}
|
|
|
|
|
|
|
|
static unsigned int get32bit(unsigned char *doh, int index)
|
|
|
|
{
|
|
|
|
return (doh[index] << 24) | (doh[index + 1] << 16) |
|
|
|
|
(doh[index + 2] << 8) | doh[index + 3];
|
|
|
|
}
|
|
|
|
|
|
|
|
static DOHcode store_a(unsigned char *doh, int index, struct dohentry *d)
|
|
|
|
{
|
|
|
|
/* silently ignore addresses over the limit */
|
2018-06-19 22:08:05 +08:00
|
|
|
if(d->numaddr < DOH_MAX_ADDR) {
|
2018-09-06 15:16:02 +08:00
|
|
|
struct dohaddr *a = &d->addr[d->numaddr];
|
|
|
|
a->type = DNS_TYPE_A;
|
2018-10-04 17:57:29 +08:00
|
|
|
memcpy(&a->ip.v4, &doh[index], 4);
|
2018-09-06 15:16:02 +08:00
|
|
|
d->numaddr++;
|
|
|
|
}
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static DOHcode store_aaaa(unsigned char *doh, int index, struct dohentry *d)
|
|
|
|
{
|
|
|
|
/* silently ignore addresses over the limit */
|
2018-06-19 22:08:05 +08:00
|
|
|
if(d->numaddr < DOH_MAX_ADDR) {
|
2018-09-06 15:16:02 +08:00
|
|
|
struct dohaddr *a = &d->addr[d->numaddr];
|
|
|
|
a->type = DNS_TYPE_AAAA;
|
2018-10-04 17:57:29 +08:00
|
|
|
memcpy(&a->ip.v6, &doh[index], 16);
|
2018-09-06 15:16:02 +08:00
|
|
|
d->numaddr++;
|
|
|
|
}
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static DOHcode cnameappend(struct cnamestore *c,
|
|
|
|
unsigned char *src,
|
|
|
|
size_t len)
|
|
|
|
{
|
|
|
|
if(!c->alloc) {
|
|
|
|
c->allocsize = len + 1;
|
|
|
|
c->alloc = malloc(c->allocsize);
|
|
|
|
if(!c->alloc)
|
|
|
|
return DOH_OUT_OF_MEM;
|
|
|
|
}
|
|
|
|
else if(c->allocsize < (c->allocsize + len + 1)) {
|
|
|
|
char *ptr;
|
|
|
|
c->allocsize += len + 1;
|
|
|
|
ptr = realloc(c->alloc, c->allocsize);
|
|
|
|
if(!ptr) {
|
|
|
|
free(c->alloc);
|
|
|
|
return DOH_OUT_OF_MEM;
|
|
|
|
}
|
|
|
|
c->alloc = ptr;
|
|
|
|
}
|
|
|
|
memcpy(&c->alloc[c->len], src, len);
|
|
|
|
c->len += len;
|
|
|
|
c->alloc[c->len] = 0; /* keep it zero terminated */
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static DOHcode store_cname(unsigned char *doh,
|
|
|
|
size_t dohlen,
|
|
|
|
unsigned int index,
|
|
|
|
struct dohentry *d)
|
|
|
|
{
|
2018-06-19 22:08:05 +08:00
|
|
|
struct cnamestore *c;
|
2018-09-06 15:16:02 +08:00
|
|
|
unsigned int loop = 128; /* a valid DNS name can never loop this much */
|
|
|
|
unsigned char length;
|
2018-06-19 22:08:05 +08:00
|
|
|
|
|
|
|
if(d->numcname == DOH_MAX_CNAME)
|
|
|
|
return DOH_OK; /* skip! */
|
|
|
|
|
|
|
|
c = &d->cname[d->numcname++];
|
2018-09-06 15:16:02 +08:00
|
|
|
do {
|
|
|
|
if(index >= dohlen)
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
length = doh[index];
|
|
|
|
if((length & 0xc0) == 0xc0) {
|
|
|
|
int newpos;
|
|
|
|
/* name pointer, get the new offset (14 bits) */
|
|
|
|
if((index + 1) >= dohlen)
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
/* move to the the new index */
|
|
|
|
newpos = (length & 0x3f) << 8 | doh[index + 1];
|
|
|
|
index = newpos;
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
else if(length & 0xc0)
|
|
|
|
return DOH_DNS_BAD_LABEL; /* bad input */
|
|
|
|
else
|
|
|
|
index++;
|
|
|
|
|
|
|
|
if(length) {
|
|
|
|
DOHcode rc;
|
|
|
|
if(c->len) {
|
|
|
|
rc = cnameappend(c, (unsigned char *)".", 1);
|
|
|
|
if(rc)
|
|
|
|
return rc;
|
|
|
|
}
|
|
|
|
if((index + length) > dohlen)
|
|
|
|
return DOH_DNS_BAD_LABEL;
|
|
|
|
|
|
|
|
rc = cnameappend(c, &doh[index], length);
|
|
|
|
if(rc)
|
|
|
|
return rc;
|
|
|
|
index += length;
|
|
|
|
}
|
|
|
|
} while(length && --loop);
|
|
|
|
|
|
|
|
if(!loop)
|
|
|
|
return DOH_DNS_LABEL_LOOP;
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static DOHcode rdata(unsigned char *doh,
|
|
|
|
size_t dohlen,
|
|
|
|
unsigned short rdlength,
|
|
|
|
unsigned short type,
|
|
|
|
int index,
|
|
|
|
struct dohentry *d)
|
|
|
|
{
|
|
|
|
/* RDATA
|
|
|
|
- A (TYPE 1): 4 bytes
|
|
|
|
- AAAA (TYPE 28): 16 bytes
|
|
|
|
- NS (TYPE 2): N bytes */
|
|
|
|
DOHcode rc;
|
|
|
|
|
|
|
|
switch(type) {
|
|
|
|
case DNS_TYPE_A:
|
|
|
|
if(rdlength != 4)
|
|
|
|
return DOH_DNS_RDATA_LEN;
|
|
|
|
rc = store_a(doh, index, d);
|
|
|
|
if(rc)
|
|
|
|
return rc;
|
|
|
|
break;
|
|
|
|
case DNS_TYPE_AAAA:
|
|
|
|
if(rdlength != 16)
|
|
|
|
return DOH_DNS_RDATA_LEN;
|
|
|
|
rc = store_aaaa(doh, index, d);
|
|
|
|
if(rc)
|
|
|
|
return rc;
|
|
|
|
break;
|
|
|
|
case DNS_TYPE_CNAME:
|
|
|
|
rc = store_cname(doh, dohlen, index, d);
|
|
|
|
if(rc)
|
|
|
|
return rc;
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
/* unsupported type, just skip it */
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
return DOH_OK;
|
|
|
|
}
|
|
|
|
|
2018-10-04 18:13:06 +08:00
|
|
|
static void init_dohentry(struct dohentry *de)
|
|
|
|
{
|
|
|
|
memset(de, 0, sizeof(*de));
|
|
|
|
de->ttl = INT_MAX;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2018-06-19 22:08:05 +08:00
|
|
|
UNITTEST DOHcode doh_decode(unsigned char *doh,
|
|
|
|
size_t dohlen,
|
|
|
|
DNStype dnstype,
|
|
|
|
struct dohentry *d)
|
2018-09-06 15:16:02 +08:00
|
|
|
{
|
|
|
|
unsigned char rcode;
|
|
|
|
unsigned short qdcount;
|
|
|
|
unsigned short ancount;
|
|
|
|
unsigned short type = 0;
|
|
|
|
unsigned short class;
|
|
|
|
unsigned short rdlength;
|
|
|
|
unsigned short nscount;
|
|
|
|
unsigned short arcount;
|
|
|
|
unsigned int index = 12;
|
|
|
|
DOHcode rc;
|
|
|
|
|
|
|
|
if(dohlen < 12)
|
|
|
|
return DOH_TOO_SMALL_BUFFER; /* too small */
|
2018-12-05 22:21:27 +08:00
|
|
|
if(!doh || doh[0] || doh[1])
|
2018-09-06 15:16:02 +08:00
|
|
|
return DOH_DNS_BAD_ID; /* bad ID */
|
|
|
|
rcode = doh[3] & 0x0f;
|
|
|
|
if(rcode)
|
|
|
|
return DOH_DNS_BAD_RCODE; /* bad rcode */
|
|
|
|
|
|
|
|
qdcount = get16bit(doh, 4);
|
|
|
|
while(qdcount) {
|
|
|
|
rc = skipqname(doh, dohlen, &index);
|
|
|
|
if(rc)
|
|
|
|
return rc; /* bad qname */
|
|
|
|
if(dohlen < (index + 4))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
index += 4; /* skip question's type and class */
|
|
|
|
qdcount--;
|
|
|
|
}
|
|
|
|
|
|
|
|
ancount = get16bit(doh, 6);
|
|
|
|
while(ancount) {
|
|
|
|
unsigned int ttl;
|
|
|
|
|
|
|
|
rc = skipqname(doh, dohlen, &index);
|
|
|
|
if(rc)
|
|
|
|
return rc; /* bad qname */
|
|
|
|
|
|
|
|
if(dohlen < (index + 2))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
type = get16bit(doh, index);
|
|
|
|
if((type != DNS_TYPE_CNAME) && (type != dnstype))
|
|
|
|
/* Not the same type as was asked for nor CNAME */
|
|
|
|
return DOH_DNS_UNEXPECTED_TYPE;
|
|
|
|
index += 2;
|
|
|
|
|
|
|
|
if(dohlen < (index + 2))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
class = get16bit(doh, index);
|
|
|
|
if(DNS_CLASS_IN != class)
|
|
|
|
return DOH_DNS_UNEXPECTED_CLASS; /* unsupported */
|
|
|
|
index += 2;
|
|
|
|
|
|
|
|
if(dohlen < (index + 4))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
ttl = get32bit(doh, index);
|
|
|
|
if(ttl < d->ttl)
|
|
|
|
d->ttl = ttl;
|
|
|
|
index += 4;
|
|
|
|
|
|
|
|
if(dohlen < (index + 2))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
rdlength = get16bit(doh, index);
|
|
|
|
index += 2;
|
|
|
|
if(dohlen < (index + rdlength))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
rc = rdata(doh, dohlen, rdlength, type, index, d);
|
|
|
|
if(rc)
|
|
|
|
return rc; /* bad rdata */
|
|
|
|
index += rdlength;
|
|
|
|
ancount--;
|
|
|
|
}
|
|
|
|
|
|
|
|
nscount = get16bit(doh, 8);
|
|
|
|
while(nscount) {
|
|
|
|
rc = skipqname(doh, dohlen, &index);
|
|
|
|
if(rc)
|
|
|
|
return rc; /* bad qname */
|
|
|
|
|
|
|
|
if(dohlen < (index + 8))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
index += 2 + 2 + 4; /* type, class and ttl */
|
|
|
|
|
|
|
|
if(dohlen < (index + 2))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
rdlength = get16bit(doh, index);
|
|
|
|
index += 2;
|
|
|
|
if(dohlen < (index + rdlength))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
index += rdlength;
|
|
|
|
nscount--;
|
|
|
|
}
|
|
|
|
|
|
|
|
arcount = get16bit(doh, 10);
|
|
|
|
while(arcount) {
|
|
|
|
rc = skipqname(doh, dohlen, &index);
|
|
|
|
if(rc)
|
|
|
|
return rc; /* bad qname */
|
|
|
|
|
|
|
|
if(dohlen < (index + 8))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
index += 2 + 2 + 4; /* type, class and ttl */
|
|
|
|
|
|
|
|
if(dohlen < (index + 2))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
|
|
|
|
rdlength = get16bit(doh, index);
|
|
|
|
index += 2;
|
|
|
|
if(dohlen < (index + rdlength))
|
|
|
|
return DOH_DNS_OUT_OF_RANGE;
|
|
|
|
index += rdlength;
|
|
|
|
arcount--;
|
|
|
|
}
|
|
|
|
|
|
|
|
if(index != dohlen)
|
|
|
|
return DOH_DNS_MALFORMAT; /* something is wrong */
|
|
|
|
|
|
|
|
if((type != DNS_TYPE_NS) && !d->numcname && !d->numaddr)
|
|
|
|
/* nothing stored! */
|
|
|
|
return DOH_NO_CONTENT;
|
|
|
|
|
|
|
|
return DOH_OK; /* ok */
|
|
|
|
}
|
|
|
|
|
2018-10-17 05:35:44 +08:00
|
|
|
#ifndef CURL_DISABLE_VERBOSE_STRINGS
|
2018-09-06 15:16:02 +08:00
|
|
|
static void showdoh(struct Curl_easy *data,
|
|
|
|
struct dohentry *d)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
infof(data, "TTL: %u seconds\n", d->ttl);
|
|
|
|
for(i = 0; i < d->numaddr; i++) {
|
|
|
|
struct dohaddr *a = &d->addr[i];
|
|
|
|
if(a->type == DNS_TYPE_A) {
|
2018-10-04 17:57:29 +08:00
|
|
|
infof(data, "DOH A: %u.%u.%u.%u\n",
|
|
|
|
a->ip.v4[0], a->ip.v4[1],
|
|
|
|
a->ip.v4[2], a->ip.v4[3]);
|
2018-09-06 15:16:02 +08:00
|
|
|
}
|
|
|
|
else if(a->type == DNS_TYPE_AAAA) {
|
|
|
|
int j;
|
|
|
|
char buffer[128];
|
|
|
|
char *ptr;
|
|
|
|
size_t len;
|
2018-11-22 16:01:24 +08:00
|
|
|
msnprintf(buffer, 128, "DOH AAAA: ");
|
2018-09-06 15:16:02 +08:00
|
|
|
ptr = &buffer[10];
|
|
|
|
len = 118;
|
|
|
|
for(j = 0; j < 16; j += 2) {
|
|
|
|
size_t l;
|
2018-11-22 16:01:24 +08:00
|
|
|
msnprintf(ptr, len, "%s%02x%02x", j?":":"", d->addr[i].ip.v6[j],
|
|
|
|
d->addr[i].ip.v6[j + 1]);
|
2018-09-06 15:16:02 +08:00
|
|
|
l = strlen(ptr);
|
|
|
|
len -= l;
|
|
|
|
ptr += l;
|
|
|
|
}
|
|
|
|
infof(data, "%s\n", buffer);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
for(i = 0; i < d->numcname; i++) {
|
|
|
|
infof(data, "CNAME: %s\n", d->cname[i].alloc);
|
|
|
|
}
|
|
|
|
}
|
2018-10-17 05:35:44 +08:00
|
|
|
#else
|
|
|
|
#define showdoh(x,y)
|
|
|
|
#endif
|
2018-09-06 15:16:02 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* doh2ai()
|
|
|
|
*
|
|
|
|
* This function returns a pointer to the first element of a newly allocated
|
|
|
|
* Curl_addrinfo struct linked list filled with the data from a set of DOH
|
|
|
|
* lookups. Curl_addrinfo is meant to work like the addrinfo struct does for
|
|
|
|
* a IPv6 stack, but usable also for IPv4, all hosts and environments.
|
|
|
|
*
|
|
|
|
* The memory allocated by this function *MUST* be free'd later on calling
|
|
|
|
* Curl_freeaddrinfo(). For each successful call to this function there
|
|
|
|
* must be an associated call later to Curl_freeaddrinfo().
|
|
|
|
*/
|
|
|
|
|
|
|
|
static Curl_addrinfo *
|
|
|
|
doh2ai(const struct dohentry *de, const char *hostname, int port)
|
|
|
|
{
|
|
|
|
Curl_addrinfo *ai;
|
|
|
|
Curl_addrinfo *prevai = NULL;
|
|
|
|
Curl_addrinfo *firstai = NULL;
|
|
|
|
struct sockaddr_in *addr;
|
|
|
|
#ifdef ENABLE_IPV6
|
|
|
|
struct sockaddr_in6 *addr6;
|
|
|
|
#endif
|
|
|
|
CURLcode result = CURLE_OK;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if(!de)
|
|
|
|
/* no input == no output! */
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
for(i = 0; i < de->numaddr; i++) {
|
|
|
|
size_t ss_size;
|
|
|
|
CURL_SA_FAMILY_T addrtype;
|
|
|
|
if(de->addr[i].type == DNS_TYPE_AAAA) {
|
|
|
|
#ifndef ENABLE_IPV6
|
|
|
|
/* we can't handle IPv6 addresses */
|
|
|
|
continue;
|
|
|
|
#else
|
|
|
|
ss_size = sizeof(struct sockaddr_in6);
|
|
|
|
addrtype = AF_INET6;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
else {
|
|
|
|
ss_size = sizeof(struct sockaddr_in);
|
|
|
|
addrtype = AF_INET;
|
|
|
|
}
|
|
|
|
|
|
|
|
ai = calloc(1, sizeof(Curl_addrinfo));
|
|
|
|
if(!ai) {
|
|
|
|
result = CURLE_OUT_OF_MEMORY;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
ai->ai_canonname = strdup(hostname);
|
|
|
|
if(!ai->ai_canonname) {
|
|
|
|
result = CURLE_OUT_OF_MEMORY;
|
|
|
|
free(ai);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
ai->ai_addr = calloc(1, ss_size);
|
|
|
|
if(!ai->ai_addr) {
|
|
|
|
result = CURLE_OUT_OF_MEMORY;
|
|
|
|
free(ai->ai_canonname);
|
|
|
|
free(ai);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if(!firstai)
|
|
|
|
/* store the pointer we want to return from this function */
|
|
|
|
firstai = ai;
|
|
|
|
|
|
|
|
if(prevai)
|
|
|
|
/* make the previous entry point to this */
|
|
|
|
prevai->ai_next = ai;
|
|
|
|
|
|
|
|
ai->ai_family = addrtype;
|
|
|
|
|
|
|
|
/* we return all names as STREAM, so when using this address for TFTP
|
|
|
|
the type must be ignored and conn->socktype be used instead! */
|
|
|
|
ai->ai_socktype = SOCK_STREAM;
|
|
|
|
|
|
|
|
ai->ai_addrlen = (curl_socklen_t)ss_size;
|
|
|
|
|
|
|
|
/* leave the rest of the struct filled with zero */
|
|
|
|
|
|
|
|
switch(ai->ai_family) {
|
|
|
|
case AF_INET:
|
|
|
|
addr = (void *)ai->ai_addr; /* storage area for this info */
|
2018-10-04 17:57:29 +08:00
|
|
|
DEBUGASSERT(sizeof(struct in_addr) == sizeof(de->addr[i].ip.v4));
|
2018-09-06 15:16:02 +08:00
|
|
|
memcpy(&addr->sin_addr, &de->addr[i].ip.v4, sizeof(struct in_addr));
|
|
|
|
addr->sin_family = (CURL_SA_FAMILY_T)addrtype;
|
|
|
|
addr->sin_port = htons((unsigned short)port);
|
|
|
|
break;
|
|
|
|
|
|
|
|
#ifdef ENABLE_IPV6
|
|
|
|
case AF_INET6:
|
|
|
|
addr6 = (void *)ai->ai_addr; /* storage area for this info */
|
2018-10-04 17:57:29 +08:00
|
|
|
DEBUGASSERT(sizeof(struct in6_addr) == sizeof(de->addr[i].ip.v6));
|
2018-09-06 15:16:02 +08:00
|
|
|
memcpy(&addr6->sin6_addr, &de->addr[i].ip.v6, sizeof(struct in6_addr));
|
|
|
|
addr6->sin6_family = (CURL_SA_FAMILY_T)addrtype;
|
|
|
|
addr6->sin6_port = htons((unsigned short)port);
|
|
|
|
break;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
prevai = ai;
|
|
|
|
}
|
|
|
|
|
|
|
|
if(result) {
|
|
|
|
Curl_freeaddrinfo(firstai);
|
|
|
|
firstai = NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
return firstai;
|
|
|
|
}
|
|
|
|
|
2018-10-17 05:35:44 +08:00
|
|
|
#ifndef CURL_DISABLE_VERBOSE_STRINGS
|
2018-09-06 15:16:02 +08:00
|
|
|
static const char *type2name(DNStype dnstype)
|
|
|
|
{
|
|
|
|
return (dnstype == DNS_TYPE_A)?"A":"AAAA";
|
|
|
|
}
|
2018-10-17 05:35:44 +08:00
|
|
|
#endif
|
2018-09-06 15:16:02 +08:00
|
|
|
|
2018-06-19 22:08:05 +08:00
|
|
|
UNITTEST void de_cleanup(struct dohentry *d)
|
2018-09-06 15:16:02 +08:00
|
|
|
{
|
|
|
|
int i = 0;
|
|
|
|
for(i = 0; i < d->numcname; i++) {
|
|
|
|
free(d->cname[i].alloc);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
CURLcode Curl_doh_is_resolved(struct connectdata *conn,
|
|
|
|
struct Curl_dns_entry **dnsp)
|
|
|
|
{
|
|
|
|
struct Curl_easy *data = conn->data;
|
|
|
|
*dnsp = NULL; /* defaults to no response */
|
|
|
|
|
|
|
|
if(!data->req.doh.probe[0].easy && !data->req.doh.probe[1].easy) {
|
|
|
|
failf(data, "Could not DOH-resolve: %s", conn->async.hostname);
|
|
|
|
return conn->bits.proxy?CURLE_COULDNT_RESOLVE_PROXY:
|
|
|
|
CURLE_COULDNT_RESOLVE_HOST;
|
|
|
|
}
|
|
|
|
else if(!data->req.doh.pending) {
|
|
|
|
DOHcode rc;
|
|
|
|
DOHcode rc2;
|
|
|
|
struct dohentry de;
|
|
|
|
struct Curl_dns_entry *dns;
|
|
|
|
struct Curl_addrinfo *ai;
|
|
|
|
/* remove DOH handles from multi handle and close them */
|
|
|
|
curl_multi_remove_handle(data->multi, data->req.doh.probe[0].easy);
|
|
|
|
Curl_close(data->req.doh.probe[0].easy);
|
|
|
|
curl_multi_remove_handle(data->multi, data->req.doh.probe[1].easy);
|
|
|
|
Curl_close(data->req.doh.probe[1].easy);
|
|
|
|
|
|
|
|
/* parse the responses, create the struct and return it! */
|
2018-10-04 18:13:06 +08:00
|
|
|
init_dohentry(&de);
|
2018-09-06 15:16:02 +08:00
|
|
|
rc = doh_decode(data->req.doh.probe[0].serverdoh.memory,
|
|
|
|
data->req.doh.probe[0].serverdoh.size,
|
|
|
|
data->req.doh.probe[0].dnstype,
|
|
|
|
&de);
|
|
|
|
free(data->req.doh.probe[0].serverdoh.memory);
|
|
|
|
if(rc) {
|
|
|
|
infof(data, "DOH: %s type %s for %s\n", doh_strerror(rc),
|
|
|
|
type2name(data->req.doh.probe[0].dnstype),
|
|
|
|
data->req.doh.host);
|
|
|
|
}
|
|
|
|
rc2 = doh_decode(data->req.doh.probe[1].serverdoh.memory,
|
|
|
|
data->req.doh.probe[1].serverdoh.size,
|
|
|
|
data->req.doh.probe[1].dnstype,
|
|
|
|
&de);
|
|
|
|
free(data->req.doh.probe[1].serverdoh.memory);
|
|
|
|
if(rc2) {
|
2018-11-26 18:40:26 +08:00
|
|
|
infof(data, "DOH: %s type %s for %s\n", doh_strerror(rc2),
|
2018-09-06 15:16:02 +08:00
|
|
|
type2name(data->req.doh.probe[1].dnstype),
|
|
|
|
data->req.doh.host);
|
|
|
|
}
|
|
|
|
if(!rc || !rc2) {
|
|
|
|
infof(data, "DOH Host name: %s\n", data->req.doh.host);
|
|
|
|
showdoh(data, &de);
|
|
|
|
|
|
|
|
ai = doh2ai(&de, data->req.doh.host, data->req.doh.port);
|
|
|
|
if(!ai) {
|
|
|
|
de_cleanup(&de);
|
|
|
|
return CURLE_OUT_OF_MEMORY;
|
|
|
|
}
|
|
|
|
|
|
|
|
if(data->share)
|
|
|
|
Curl_share_lock(data, CURL_LOCK_DATA_DNS, CURL_LOCK_ACCESS_SINGLE);
|
|
|
|
|
|
|
|
/* we got a response, store it in the cache */
|
|
|
|
dns = Curl_cache_addr(data, ai, data->req.doh.host, data->req.doh.port);
|
|
|
|
|
|
|
|
if(data->share)
|
|
|
|
Curl_share_unlock(data, CURL_LOCK_DATA_DNS);
|
|
|
|
|
|
|
|
de_cleanup(&de);
|
|
|
|
if(!dns)
|
|
|
|
/* returned failure, bail out nicely */
|
|
|
|
Curl_freeaddrinfo(ai);
|
|
|
|
else {
|
|
|
|
conn->async.dns = dns;
|
|
|
|
*dnsp = dns;
|
|
|
|
return CURLE_OK;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
de_cleanup(&de);
|
|
|
|
|
|
|
|
return CURLE_COULDNT_RESOLVE_HOST;
|
|
|
|
}
|
|
|
|
|
|
|
|
return CURLE_OK;
|
|
|
|
}
|