1 #ifndef HEADER_CURL_DOH_H 2 #define HEADER_CURL_DOH_H 3 /*************************************************************************** 4 * _ _ ____ _ 5 * Project ___| | | | _ \| | 6 * / __| | | | |_) | | 7 * | (__| |_| | _ <| |___ 8 * \___|\___/|_| \_\_____| 9 * 10 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 11 * 12 * This software is licensed as described in the file COPYING, which 13 * you should have received as part of this distribution. The terms 14 * are also available at https://curl.se/docs/copyright.html. 15 * 16 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 17 * copies of the Software, and permit persons to whom the Software is 18 * furnished to do so, under the terms of the COPYING file. 19 * 20 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 21 * KIND, either express or implied. 22 * 23 * SPDX-License-Identifier: curl 24 * 25 ***************************************************************************/ 26 27 #include "urldata.h" 28 #include "curl_addrinfo.h" 29 #ifdef USE_HTTPSRR 30 # include <stdint.h> 31 #endif 32 33 #ifndef CURL_DISABLE_DOH 34 35 typedef enum { 36 DOH_OK, 37 DOH_DNS_BAD_LABEL, /* 1 */ 38 DOH_DNS_OUT_OF_RANGE, /* 2 */ 39 DOH_DNS_LABEL_LOOP, /* 3 */ 40 DOH_TOO_SMALL_BUFFER, /* 4 */ 41 DOH_OUT_OF_MEM, /* 5 */ 42 DOH_DNS_RDATA_LEN, /* 6 */ 43 DOH_DNS_MALFORMAT, /* 7 */ 44 DOH_DNS_BAD_RCODE, /* 8 - no such name */ 45 DOH_DNS_UNEXPECTED_TYPE, /* 9 */ 46 DOH_DNS_UNEXPECTED_CLASS, /* 10 */ 47 DOH_NO_CONTENT, /* 11 */ 48 DOH_DNS_BAD_ID, /* 12 */ 49 DOH_DNS_NAME_TOO_LONG /* 13 */ 50 } DOHcode; 51 52 typedef enum { 53 DNS_TYPE_A = 1, 54 DNS_TYPE_NS = 2, 55 DNS_TYPE_CNAME = 5, 56 DNS_TYPE_AAAA = 28, 57 DNS_TYPE_DNAME = 39, /* RFC6672 */ 58 DNS_TYPE_HTTPS = 65 59 } DNStype; 60 61 /* one of these for each DoH request */ 62 struct dnsprobe { 63 CURL *easy; 64 DNStype dnstype; 65 unsigned char dohbuffer[512]; 66 size_t dohlen; 67 struct dynbuf serverdoh; 68 }; 69 70 struct dohdata { 71 struct curl_slist *headers; 72 struct dnsprobe probe[DOH_PROBE_SLOTS]; 73 unsigned int pending; /* still outstanding requests */ 74 int port; 75 const char *host; 76 }; 77 78 /* 79 * Curl_doh() resolve a name using DoH (DNS-over-HTTPS). It resolves a name 80 * and returns a 'Curl_addrinfo *' with the address information. 81 */ 82 83 struct Curl_addrinfo *Curl_doh(struct Curl_easy *data, 84 const char *hostname, 85 int port, 86 int *waitp); 87 88 CURLcode Curl_doh_is_resolved(struct Curl_easy *data, 89 struct Curl_dns_entry **dns); 90 91 #define DOH_MAX_ADDR 24 92 #define DOH_MAX_CNAME 4 93 #define DOH_MAX_HTTPS 4 94 95 struct dohaddr { 96 int type; 97 union { 98 unsigned char v4[4]; /* network byte order */ 99 unsigned char v6[16]; 100 } ip; 101 }; 102 103 #ifdef USE_HTTPSRR 104 105 /* 106 * These are the code points for DNS wire format SvcParams as 107 * per draft-ietf-dnsop-svcb-https 108 * Not all are supported now, and even those that are may need 109 * more work in future to fully support the spec. 110 */ 111 #define HTTPS_RR_CODE_ALPN 0x01 112 #define HTTPS_RR_CODE_NO_DEF_ALPN 0x02 113 #define HTTPS_RR_CODE_PORT 0x03 114 #define HTTPS_RR_CODE_IPV4 0x04 115 #define HTTPS_RR_CODE_ECH 0x05 116 #define HTTPS_RR_CODE_IPV6 0x06 117 118 /* 119 * These may need escaping when found within an alpn string 120 * value. 121 */ 122 #define COMMA_CHAR ',' 123 #define BACKSLASH_CHAR '\\' 124 125 struct dohhttps_rr { 126 uint16_t len; /* raw encoded length */ 127 unsigned char *val; /* raw encoded octets */ 128 }; 129 #endif 130 131 struct dohentry { 132 struct dynbuf cname[DOH_MAX_CNAME]; 133 struct dohaddr addr[DOH_MAX_ADDR]; 134 int numaddr; 135 unsigned int ttl; 136 int numcname; 137 #ifdef USE_HTTPSRR 138 struct dohhttps_rr https_rrs[DOH_MAX_HTTPS]; 139 int numhttps_rrs; 140 #endif 141 }; 142 143 144 #ifdef DEBUGBUILD 145 DOHcode doh_encode(const char *host, 146 DNStype dnstype, 147 unsigned char *dnsp, /* buffer */ 148 size_t len, /* buffer size */ 149 size_t *olen); /* output length */ 150 DOHcode doh_decode(const unsigned char *doh, 151 size_t dohlen, 152 DNStype dnstype, 153 struct dohentry *d); 154 void de_init(struct dohentry *d); 155 void de_cleanup(struct dohentry *d); 156 #endif 157 158 extern struct curl_trc_feat Curl_doh_trc; 159 160 #else /* if DoH is disabled */ 161 #define Curl_doh(a,b,c,d) NULL 162 #define Curl_doh_is_resolved(x,y) CURLE_COULDNT_RESOLVE_HOST 163 #endif 164 165 #endif /* HEADER_CURL_DOH_H */ 166
