test1658: add unit test for the HTTPS RR decoder

Made the HTTPS-RR parser a little stricter while at it.

Drop the ALPN escape handling, that was not needed.

Make the hode handle (and ignore) duplicate ALPN entries.

Closes #16972
This commit is contained in:
Daniel Stenberg 2025-04-04 23:21:41 +02:00
parent 023cc8d595
commit badfb951ec
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GPG key ID: 5CC908FDB71E12C2
9 changed files with 645 additions and 77 deletions

View file

@ -38,76 +38,67 @@
#include "curl_memory.h"
#include "memdebug.h"
CURLcode Curl_httpsrr_decode_alpn(const unsigned char *cp, size_t len,
unsigned char *alpns)
#define MAX_ALPN_LENGTH 255
static CURLcode httpsrr_decode_alpn(const char *cp, size_t len,
unsigned char *alpns)
{
/*
* spec here is as per RFC 9460, section-7.1.1
* encoding is a concatenated list of strings each preceded by a one
* octet length
* output is comma-sep list of the strings
* implementations may or may not handle quoting of comma within
* string values, so we might see a comma within the wire format
* version of a string, in which case we will precede that by a
* backslash - same goes for a backslash character, and of course
* we need to use two backslashes in strings when we mean one;-)
* The wire-format value for "alpn" consists of at least one alpn-id
* prefixed by its length as a single octet, and these length-value pairs
* are concatenated to form the SvcParamValue. These pairs MUST exactly fill
* the SvcParamValue; otherwise, the SvcParamValue is malformed.
*/
struct dynbuf dval;
int idnum = 0;
Curl_dyn_init(&dval, DYN_DOH_RESPONSE);
while(len > 0) {
size_t tlen = (size_t) *cp++;
size_t i;
enum alpnid id;
len--;
if(tlen > len)
goto err;
/* add escape char if needed, clunky but easier to read */
for(i = 0; i != tlen; i++) {
if('\\' == *cp || ',' == *cp) {
if(Curl_dyn_addn(&dval, "\\", 1))
goto err;
}
if(Curl_dyn_addn(&dval, cp++, 1))
goto err;
}
len -= tlen;
return CURLE_BAD_CONTENT_ENCODING;
/* we only store ALPN ids we know about */
id = Curl_alpn2alpnid(Curl_dyn_ptr(&dval), Curl_dyn_len(&dval));
id = Curl_alpn2alpnid(cp, tlen);
if(id != ALPN_none) {
if(idnum == MAX_HTTPSRR_ALPNS)
break;
alpns[idnum++] = (unsigned char)id;
if(idnum && memchr(alpns, id, idnum))
/* this ALPN id is already stored */
;
else
alpns[idnum++] = (unsigned char)id;
}
Curl_dyn_reset(&dval);
cp += tlen;
len -= tlen;
}
Curl_dyn_free(&dval);
if(idnum < MAX_HTTPSRR_ALPNS)
alpns[idnum] = ALPN_none; /* terminate the list */
return CURLE_OK;
err:
Curl_dyn_free(&dval);
return CURLE_BAD_CONTENT_ENCODING;
}
CURLcode Curl_httpsrr_set(struct Curl_easy *data,
struct Curl_https_rrinfo *hi,
uint16_t rrkey, const uint8_t *val, size_t vlen)
{
CURLcode result = CURLE_OK;
switch(rrkey) {
case HTTPS_RR_CODE_MANDATORY:
CURL_TRC_DNS(data, "HTTPS RR MANDATORY left to implement");
break;
case HTTPS_RR_CODE_ALPN: /* str_list */
Curl_httpsrr_decode_alpn(val, vlen, hi->alpns);
result = httpsrr_decode_alpn((const char *)val, vlen, hi->alpns);
CURL_TRC_DNS(data, "HTTPS RR ALPN: %u %u %u %u",
hi->alpns[0], hi->alpns[1], hi->alpns[2], hi->alpns[3]);
break;
case HTTPS_RR_CODE_NO_DEF_ALPN:
if(vlen) /* no data */
return CURLE_BAD_FUNCTION_ARGUMENT;
hi->no_def_alpn = TRUE;
CURL_TRC_DNS(data, "HTTPS RR no-def-alpn");
break;
case HTTPS_RR_CODE_IPV4: /* addr4 list */
if(!vlen)
if(!vlen || (vlen & 3)) /* the size must be 4-byte aligned */
return CURLE_BAD_FUNCTION_ARGUMENT;
hi->ipv4hints = Curl_memdup(val, vlen);
if(!hi->ipv4hints)
@ -125,7 +116,7 @@ CURLcode Curl_httpsrr_set(struct Curl_easy *data,
CURL_TRC_DNS(data, "HTTPS RR ECH");
break;
case HTTPS_RR_CODE_IPV6: /* addr6 list */
if(!vlen)
if(!vlen || (vlen & 15)) /* the size must be 16-byte aligned */
return CURLE_BAD_FUNCTION_ARGUMENT;
hi->ipv6hints = Curl_memdup(val, vlen);
if(!hi->ipv6hints)
@ -143,7 +134,7 @@ CURLcode Curl_httpsrr_set(struct Curl_easy *data,
CURL_TRC_DNS(data, "HTTPS RR unknown code");
break;
}
return CURLE_OK;
return result;
}
struct Curl_https_rrinfo *