sinjuginas/haproxy
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

MINOR: http: extract content-length parsing from H2

Browse Source 
Extract function h2_parse_cont_len_header() in the generic HTTP module.
This allows to reuse it for all HTTP/x parsers. The function is now
available as http_parse_cont_len_header().

Most notably, this will be reused in the next bugfix for the H3 parser.
This is necessary to check that content-length header match the length
of DATA frames.

Thus, it must be backported to 2.6.

(cherry picked from commit 15f3cc4b38)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 76d3becee5c10aacabb5cb26b6776c00ca5b9ae6)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
This commit is contained in:
Amaury Denoyelle 2022-12-08 16:53:58 +01:00 committed by Christopher Faulet
parent 1e4d26aee5
commit d1975e2fc7
3 changed files with 90 additions and 74 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/haproxy/http.h
View File

@ -42,6 +42,8 @@ int http_validate_scheme(const struct ist schm);
struct ist http_parse_scheme(struct http_uri_parser *parser);
struct ist http_parse_authority(struct http_uri_parser *parser, int no_userinfo);
struct ist http_parse_path(struct http_uri_parser *parser);
int http_parse_cont_len_header(struct ist *value, unsigned long long *body_len,
int not_first);
int http_header_match2(const char *hdr, const char *end,
const char *name, int len);
char *http_find_hdr_value_end(char *s, const char *e);

80
src/h2.c
View File

@ -66,78 +66,6 @@ static int has_forbidden_char(const struct ist ist, const char *start)
return 0;
}
/* Parse the Content-Length header field of an HTTP/2 request. The function
* checks all possible occurrences of a comma-delimited value, and verifies
* if any of them doesn't match a previous value. It returns <0 if a value
* differs, 0 if the whole header can be dropped (i.e. already known), or >0
* if the value can be indexed (first one). In the last case, the value might
* be adjusted and the caller must only add the updated value.
*/
int h2_parse_cont_len_header(unsigned int *msgf, struct ist *value, unsigned long long *body_len)
{
char *e, *n;
unsigned long long cl;
int not_first = !!(*msgf & H2_MSGF_BODY_CL);
struct ist word;
word.ptr = value->ptr - 1; // -1 for next loop's pre-increment
e = value->ptr + value->len;
while (++word.ptr < e) {
/* skip leading delimiter and blanks */
if (unlikely(HTTP_IS_LWS(*word.ptr)))
continue;
/* digits only now */
for (cl = 0, n = word.ptr; n < e; n++) {
unsigned int c = *n - '0';
if (unlikely(c > 9)) {
/* non-digit */
if (unlikely(n == word.ptr)) // spaces only
goto fail;
break;
}
if (unlikely(cl > ULLONG_MAX / 10ULL))
goto fail; /* multiply overflow */
cl = cl * 10ULL;
if (unlikely(cl + c < cl))
goto fail; /* addition overflow */
cl = cl + c;
}
/* keep a copy of the exact cleaned value */
word.len = n - word.ptr;
/* skip trailing LWS till next comma or EOL */
for (; n < e; n++) {
if (!HTTP_IS_LWS(*n)) {
if (unlikely(*n != ','))
goto fail;
break;
}
}
/* if duplicate, must be equal */
if (*msgf & H2_MSGF_BODY_CL && cl != *body_len)
goto fail;
/* OK, store this result as the one to be indexed */
*msgf |= H2_MSGF_BODY_CL;
*body_len = cl;
*value = word;
word.ptr = n;
}
/* here we've reached the end with a single value or a series of
* identical values, all matching previous series if any. The last
* parsed value was sent back into <value>. We just have to decide
* if this occurrence has to be indexed (it's the first one) or
* silently skipped (it's not the first one)
*/
return !not_first;
fail:
return -1;
}
/* Prepare the request line into <htx> from pseudo headers stored in <phdr[]>.
* <fields> indicates what was found so far. This should be called once at the
* detection of the first general header field or at the end of the request if
@ -479,10 +407,12 @@ int h2_make_htx_request(struct http_hdr *list, struct htx *htx, unsigned int *ms
}
if (isteq(list[idx].n, ist("content-length"))) {
ret = h2_parse_cont_len_header(msgf, &list[idx].v, body_len);
ret = http_parse_cont_len_header(&list[idx].v, body_len,
*msgf & H2_MSGF_BODY_CL);
if (ret < 0)
goto fail;
*msgf |= H2_MSGF_BODY_CL;
sl_flags |= HTX_SL_F_CLEN;
if (ret == 0)
continue; // skip this duplicate
@ -742,10 +672,12 @@ int h2_make_htx_response(struct http_hdr *list, struct htx *htx, unsigned int *m
}
if (isteq(list[idx].n, ist("content-length"))) {
ret = h2_parse_cont_len_header(msgf, &list[idx].v, body_len);
ret = http_parse_cont_len_header(&list[idx].v, body_len,
*msgf & H2_MSGF_BODY_CL);
if (ret < 0)
goto fail;
*msgf |= H2_MSGF_BODY_CL;
sl_flags |= HTX_SL_F_CLEN;
if (ret == 0)
continue; // skip this duplicate

82
src/http.c
View File

@ -677,6 +677,88 @@ struct ist http_parse_path(struct http_uri_parser *parser)
return IST_NULL;
}
/* Parse <value> Content-Length header field of an HTTP request. The function
* checks all possible occurrences of a comma-delimited value, and verifies if
* any of them doesn't match a previous value. <value> is sanitized on return
* to contain a single value if several identical values were found.
*
* <body_len> must be a valid pointer and is used to return the parsed length
* unless values differ. Also if <not_first> is true, <body_len> is assumed to
* point to previously parsed value and which must be equal to the new length.
* This is useful if an HTTP message contains several Content-Length headers.
*
* Returns <0 if a value differs, 0 if the whole header can be dropped (i.e.
* already known), or >0 if the value can be indexed (first one). In the last
* case, the value might be adjusted and the caller must only add the updated
* value.
*/
int http_parse_cont_len_header(struct ist *value, unsigned long long *body_len,
int not_first)
{
char *e, *n;
unsigned long long cl;
struct ist word;
int check_prev = not_first;
word.ptr = value->ptr - 1; // -1 for next loop's pre-increment
e = value->ptr + value->len;
while (++word.ptr < e) {
/* skip leading delimiter and blanks */
if (unlikely(HTTP_IS_LWS(*word.ptr)))
continue;
/* digits only now */
for (cl = 0, n = word.ptr; n < e; n++) {
unsigned int c = *n - '0';
if (unlikely(c > 9)) {
/* non-digit */
if (unlikely(n == word.ptr)) // spaces only
goto fail;
break;
}
if (unlikely(cl > ULLONG_MAX / 10ULL))
goto fail; /* multiply overflow */
cl = cl * 10ULL;
if (unlikely(cl + c < cl))
goto fail; /* addition overflow */
cl = cl + c;
}
/* keep a copy of the exact cleaned value */
word.len = n - word.ptr;
/* skip trailing LWS till next comma or EOL */
for (; n < e; n++) {
if (!HTTP_IS_LWS(*n)) {
if (unlikely(*n != ','))
goto fail;
break;
}
}
/* if duplicate, must be equal */
if (check_prev && cl != *body_len)
goto fail;
/* OK, store this result as the one to be indexed */
*body_len = cl;
*value = word;
word.ptr = n;
check_prev = 1;
}
/* here we've reached the end with a single value or a series of
* identical values, all matching previous series if any. The last
* parsed value was sent back into <value>. We just have to decide
* if this occurrence has to be indexed (it's the first one) or
* silently skipped (it's not the first one)
*/
return !not_first;
fail:
return -1;
}
/*
* Checks if <hdr> is exactly <name> for <len> chars, and ends with a colon.
* If so, returns the position of the first non-space character relative to