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-rw-r--r--lib/doh.c915
1 files changed, 915 insertions, 0 deletions
diff --git a/lib/doh.c b/lib/doh.c
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+++ b/lib/doh.c
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+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 2018, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+#include "urldata.h"
+#include "curl_addrinfo.h"
+#include "sendf.h"
+#include "multiif.h"
+#include "url.h"
+#include "share.h"
+#include "curl_base64.h"
+#include "connect.h"
+#include "doh.h"
+/* The last 3 #include files should be in this order */
+#include "curl_printf.h"
+#include "curl_memory.h"
+#include "memdebug.h"
+
+#define DNS_CLASS_IN 0x01
+#define DOH_MAX_RESPONSE_SIZE 3000 /* bytes */
+
+typedef enum {
+ DNS_TYPE_A = 1,
+ DNS_TYPE_NS = 2,
+ DNS_TYPE_CNAME = 5,
+ DNS_TYPE_AAAA = 28
+} DNStype;
+
+#define MAX_ADDR 24
+
+typedef enum {
+ DOH_OK,
+ DOH_DNS_BAD_LABEL, /* 1 */
+ DOH_DNS_OUT_OF_RANGE, /* 2 */
+ DOH_DNS_LABEL_LOOP, /* 3 */
+ DOH_TOO_SMALL_BUFFER, /* 4 */
+ DOH_OUT_OF_MEM, /* 5 */
+ DOH_DNS_RDATA_LEN, /* 6 */
+ DOH_DNS_MALFORMAT, /* 7 */
+ DOH_DNS_BAD_RCODE, /* 8 - no such name */
+ DOH_DNS_UNEXPECTED_TYPE, /* 9 */
+ DOH_DNS_UNEXPECTED_CLASS, /* 10 */
+ DOH_NO_CONTENT, /* 11 */
+ DOH_DNS_BAD_ID /* 12 */
+} DOHcode;
+
+static const char * const errors[]={
+ "",
+ "Bad label",
+ "Out of range",
+ "Label loop",
+ "Too small",
+ "Out of memory",
+ "RDATA length",
+ "Malformat",
+ "Bad RCODE",
+ "Unexpected TYPE",
+ "Unexpected CLASS",
+ "No content",
+ "Bad ID"
+};
+
+static const char *doh_strerror(DOHcode code)
+{
+ if((code >= DOH_OK) && (code <= DOH_DNS_BAD_ID))
+ return errors[code];
+ return "bad error code";
+}
+
+static DOHcode doh_encode(const char *host,
+ DNStype dnstype,
+ unsigned char *dnsp, /* buffer */
+ size_t len, /* buffer size */
+ size_t *olen) /* output length */
+{
+ size_t hostlen = strlen(host);
+ unsigned char *orig = dnsp;
+ const char *hostp = host;
+
+ if(len < (12 + hostlen + 4))
+ return DOH_TOO_SMALL_BUFFER;
+
+ *dnsp++ = 0; /* 16 bit id */
+ *dnsp++ = 0;
+ *dnsp++ = 0x01; /* |QR| Opcode |AA|TC|RD| Set the RD bit */
+ *dnsp++ = '\0'; /* |RA| Z | RCODE | */
+ *dnsp++ = '\0';
+ *dnsp++ = 1; /* QDCOUNT (number of entries in the question section) */
+ *dnsp++ = '\0';
+ *dnsp++ = '\0'; /* ANCOUNT */
+ *dnsp++ = '\0';
+ *dnsp++ = '\0'; /* NSCOUNT */
+ *dnsp++ = '\0';
+ *dnsp++ = '\0'; /* ARCOUNT */
+
+ /* store a QNAME */
+ do {
+ char *dot = strchr(hostp, '.');
+ size_t labellen;
+ bool found = false;
+ if(dot) {
+ found = true;
+ labellen = dot - hostp;
+ }
+ else
+ labellen = strlen(hostp);
+ if(labellen > 63)
+ /* too long label, error out */
+ return DOH_DNS_BAD_LABEL;
+ *dnsp++ = (unsigned char)labellen;
+ memcpy(dnsp, hostp, labellen);
+ dnsp += labellen;
+ hostp += labellen + 1;
+ if(!found) {
+ *dnsp++ = 0; /* terminating zero */
+ break;
+ }
+ } while(1);
+
+ *dnsp++ = '\0'; /* upper 8 bit TYPE */
+ *dnsp++ = (unsigned char)dnstype;
+ *dnsp++ = '\0'; /* upper 8 bit CLASS */
+ *dnsp++ = DNS_CLASS_IN; /* IN - "the Internet" */
+
+ *olen = dnsp - orig;
+ return DOH_OK;
+}
+
+static size_t
+doh_write_cb(void *contents, size_t size, size_t nmemb, void *userp)
+{
+ size_t realsize = size * nmemb;
+ struct dohresponse *mem = (struct dohresponse *)userp;
+
+ if((mem->size + realsize) > DOH_MAX_RESPONSE_SIZE)
+ /* suspiciously much for us */
+ return 0;
+
+ mem->memory = realloc(mem->memory, mem->size + realsize);
+ if(mem->memory == NULL)
+ /* out of memory! */
+ return 0;
+
+ memcpy(&(mem->memory[mem->size]), contents, realsize);
+ mem->size += realsize;
+
+ return realsize;
+}
+
+/* called from multi.c when this DOH transfer is complete */
+static int Curl_doh_done(struct Curl_easy *doh, CURLcode result)
+{
+ struct Curl_easy *data = doh->set.dohfor;
+ /* so one of the DOH request done for the 'data' transfer is now complete! */
+ data->req.doh.pending--;
+ infof(data, "a DOH request is completed, %d to go\n", data->req.doh.pending);
+ if(result)
+ infof(data, "DOH request %s\n", curl_easy_strerror(result));
+
+ if(!data->req.doh.pending) {
+ /* DOH completed */
+ curl_slist_free_all(data->req.doh.headers);
+ data->req.doh.headers = NULL;
+ Curl_expire(data, 0, EXPIRE_RUN_NOW);
+ }
+ return 0;
+}
+
+#define ERROR_CHECK_SETOPT(x,y) result = curl_easy_setopt(doh, x, y); \
+ if(result) goto error
+
+static CURLcode dohprobe(struct Curl_easy *data,
+ struct dnsprobe *p, DNStype dnstype,
+ const char *host,
+ const char *url, CURLM *multi,
+ struct curl_slist *headers)
+{
+ struct Curl_easy *doh = NULL;
+ char *nurl = NULL;
+ CURLcode result = CURLE_OK;
+ timediff_t timeout_ms;
+ DOHcode d = doh_encode(host, dnstype, p->dohbuffer, sizeof(p->dohbuffer),
+ &p->dohlen);
+ if(d) {
+ failf(data, "Failed to encode DOH packet [%d]\n", d);
+ return CURLE_OUT_OF_MEMORY;
+ }
+
+ p->dnstype = dnstype;
+ p->serverdoh.memory = NULL;
+ /* the memory will be grown as needed by realloc in the doh_write_cb
+ function */
+ p->serverdoh.size = 0;
+
+ /* Note: this is code for sending the DoH request with GET but there's still
+ no logic that actually enables this. We should either add that ability or
+ yank out the GET code. Discuss! */
+ if(data->set.doh_get) {
+ char *b64;
+ size_t b64len;
+ result = Curl_base64url_encode(data, (char *)p->dohbuffer, p->dohlen,
+ &b64, &b64len);
+ if(result)
+ goto error;
+ nurl = aprintf("%s?dns=%s", url, b64);
+ free(b64);
+ if(!nurl) {
+ result = CURLE_OUT_OF_MEMORY;
+ goto error;
+ }
+ url = nurl;
+ }
+
+ timeout_ms = Curl_timeleft(data, NULL, TRUE);
+
+ /* Curl_open() is the internal version of curl_easy_init() */
+ result = Curl_open(&doh);
+ if(!result) {
+ ERROR_CHECK_SETOPT(CURLOPT_URL, url);
+ ERROR_CHECK_SETOPT(CURLOPT_WRITEFUNCTION, doh_write_cb);
+ ERROR_CHECK_SETOPT(CURLOPT_WRITEDATA, (void *)&p->serverdoh);
+ if(!data->set.doh_get) {
+ ERROR_CHECK_SETOPT(CURLOPT_POSTFIELDS, &p->dohbuffer[0]);
+ ERROR_CHECK_SETOPT(CURLOPT_POSTFIELDSIZE, p->dohlen);
+ }
+ ERROR_CHECK_SETOPT(CURLOPT_HTTPHEADER, headers);
+ ERROR_CHECK_SETOPT(CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2TLS);
+#ifndef CURLDEBUG
+ /* enforce HTTPS if not debug */
+ ERROR_CHECK_SETOPT(CURLOPT_PROTOCOLS, CURLPROTO_HTTPS);
+#endif
+ ERROR_CHECK_SETOPT(CURLOPT_TIMEOUT_MS, (long)timeout_ms);
+ ERROR_CHECK_SETOPT(CURLOPT_VERBOSE, 1L);
+ doh->set.fmultidone = Curl_doh_done;
+ doh->set.dohfor = data; /* identify for which transfer this is done */
+ p->easy = doh;
+
+ /* add this transfer to the multi handle */
+ if(curl_multi_add_handle(multi, doh))
+ goto error;
+ }
+ else
+ goto error;
+ free(nurl);
+ return CURLE_OK;
+
+ error:
+ free(nurl);
+ Curl_close(doh);
+ return result;
+}
+
+/*
+ * Curl_doh() resolves a name using DOH. It resolves a name and returns a
+ * 'Curl_addrinfo *' with the address information.
+ */
+
+Curl_addrinfo *Curl_doh(struct connectdata *conn,
+ const char *hostname,
+ int port,
+ int *waitp)
+{
+ struct Curl_easy *data = conn->data;
+ CURLcode result = CURLE_OK;
+ *waitp = TRUE; /* this never returns synchronously */
+ (void)conn;
+ (void)hostname;
+ (void)port;
+
+ /* start clean, consider allocating this struct on demand */
+ memset(&data->req.doh, 0, sizeof(struct dohdata));
+
+ data->req.doh.host = hostname;
+ data->req.doh.port = port;
+ data->req.doh.headers =
+ curl_slist_append(NULL,
+ "Content-Type: application/dns-message");
+ if(!data->req.doh.headers)
+ goto error;
+
+ if(conn->ip_version != CURL_IPRESOLVE_V6) {
+ /* create IPv4 DOH request */
+ result = dohprobe(data, &data->req.doh.probe[0], DNS_TYPE_A,
+ hostname, data->set.str[STRING_DOH],
+ data->multi, data->req.doh.headers);
+ if(result)
+ goto error;
+ data->req.doh.pending++;
+ }
+
+ if(conn->ip_version != CURL_IPRESOLVE_V4) {
+ /* create IPv6 DOH request */
+ result = dohprobe(data, &data->req.doh.probe[1], DNS_TYPE_AAAA,
+ hostname, data->set.str[STRING_DOH],
+ data->multi, data->req.doh.headers);
+ if(result)
+ goto error;
+ data->req.doh.pending++;
+ }
+ return NULL;
+
+ error:
+ curl_slist_free_all(data->req.doh.headers);
+ data->req.doh.headers = NULL;
+ curl_easy_cleanup(data->req.doh.probe[0].easy);
+ data->req.doh.probe[0].easy = NULL;
+ curl_easy_cleanup(data->req.doh.probe[1].easy);
+ data->req.doh.probe[1].easy = NULL;
+ return NULL;
+}
+
+static DOHcode skipqname(unsigned char *doh, size_t dohlen,
+ unsigned int *indexp)
+{
+ unsigned char length;
+ do {
+ if(dohlen < (*indexp + 1))
+ return DOH_DNS_OUT_OF_RANGE;
+ length = doh[*indexp];
+ if((length & 0xc0) == 0xc0) {
+ /* name pointer, advance over it and be done */
+ if(dohlen < (*indexp + 2))
+ return DOH_DNS_OUT_OF_RANGE;
+ *indexp += 2;
+ break;
+ }
+ if(length & 0xc0)
+ return DOH_DNS_BAD_LABEL;
+ 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];
+}
+
+struct addr6 {
+ unsigned char byte[16];
+};
+
+struct cnamestore {
+ size_t len; /* length of cname */
+ char *alloc; /* allocated pointer */
+ size_t allocsize; /* allocated size */
+};
+
+struct dohaddr {
+ int type;
+ union {
+ unsigned int v4;
+ struct addr6 v6;
+ } ip;
+};
+
+struct dohentry {
+ unsigned int ttl;
+ int numaddr;
+ struct dohaddr addr[MAX_ADDR];
+ int numcname;
+ struct cnamestore cname[MAX_ADDR];
+};
+
+static DOHcode store_a(unsigned char *doh, int index, struct dohentry *d)
+{
+ /* silently ignore addresses over the limit */
+ if(d->numaddr < MAX_ADDR) {
+ struct dohaddr *a = &d->addr[d->numaddr];
+ a->type = DNS_TYPE_A;
+ a->ip.v4 = ntohl(get32bit(doh, index));
+ d->numaddr++;
+ }
+ return DOH_OK;
+}
+
+static DOHcode store_aaaa(unsigned char *doh, int index, struct dohentry *d)
+{
+ /* silently ignore addresses over the limit */
+ if(d->numaddr < MAX_ADDR) {
+ struct dohaddr *a = &d->addr[d->numaddr];
+ struct addr6 *inet6p = &a->ip.v6;
+ a->type = DNS_TYPE_AAAA;
+ memcpy(inet6p, &doh[index], 16);
+ 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)
+{
+ struct cnamestore *c = &d->cname[d->numcname++];
+ unsigned int loop = 128; /* a valid DNS name can never loop this much */
+ unsigned char length;
+ 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;
+}
+
+static DOHcode doh_decode(unsigned char *doh,
+ size_t dohlen,
+ DNStype dnstype,
+ struct dohentry *d)
+{
+ 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;
+
+ d->ttl = INT_MAX;
+
+ if(dohlen < 12)
+ return DOH_TOO_SMALL_BUFFER; /* too small */
+ if(doh[0] || doh[1])
+ 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 */
+}
+
+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) {
+ infof(data, "DOH A: %d.%d.%d.%d\n",
+ a->ip.v4 & 0xff, (a->ip.v4>>8) & 0xff,
+ (a->ip.v4>>16) & 0xff, a->ip.v4 >>24);
+ }
+ else if(a->type == DNS_TYPE_AAAA) {
+ int j;
+ char buffer[128];
+ char *ptr;
+ size_t len;
+ snprintf(buffer, 128, "DOH AAAA: ");
+ ptr = &buffer[10];
+ len = 118;
+ for(j = 0; j < 16; j += 2) {
+ size_t l;
+ snprintf(ptr, len, "%s%02x%02x", j?":":"", d->addr[i].ip.v6.byte[j],
+ d->addr[i].ip.v6.byte[j + 1]);
+ 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);
+ }
+}
+
+/*
+ * 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 */
+
+ 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 */
+
+ 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;
+}
+
+static const char *type2name(DNStype dnstype)
+{
+ return (dnstype == DNS_TYPE_A)?"A":"AAAA";
+}
+
+static void de_cleanup(struct dohentry *d)
+{
+ 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! */
+ memset(&de, 0, sizeof(de));
+ 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) {
+ infof(data, "DOG: %s type %s for %s\n", doh_strerror(rc2),
+ 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;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-16 17:25:46 +0000