[MEDIUM] acl: implement matching on header values

hdr(x), hdr_reg(x), hdr_beg(x), hdr_end(x), hdr_sub(x), hdr_dir(x),
hdr_dom(x), hdr_cnt(x) and hdr_val(x) have been implemented. They
apply to any of the possibly multiple values of header <x>.

Right now, hdr_val() is limited to integer matching, but it should
reasonably be upgraded to match long long ints.
This commit is contained in:
Willy Tarreau 2007-06-10 19:45:56 +02:00
parent 97be145991
commit 33a7e6901f
3 changed files with 200 additions and 16 deletions

View File

@ -102,13 +102,16 @@ struct acl_pattern {
* retrieving a value, and an acl_match_* function responsible for testing it.
*/
struct acl_test {
int i; /* integer value */
char *ptr; /* pointer to beginning of value */
int len; /* length of value at ptr, otherwise ignored */
int flags; /* ACL_TEST_F_* set to 0 on first call */
union { /* fetch_* functions context for any purpose */
void *p;
int i;
int i; /* integer value */
char *ptr; /* pointer to beginning of value */
int len; /* length of value at ptr, otherwise ignored */
int flags; /* ACL_TEST_F_* set to 0 on first call */
union { /* fetch_* functions context for any purpose */
void *p; /* any pointer */
int i; /* any integer */
long long ll; /* any long long or smaller */
double d; /* any float or double */
void *a[8]; /* any array of up to 8 pointers */
} ctx;
};

View File

@ -243,6 +243,15 @@ struct http_txn {
unsigned int flags; /* transaction flags */
};
/* This structure is used by http_find_header() to return values of headers.
* The header starts at <line>, the value at <line>+<val> for <vlen> bytes.
*/
struct hdr_ctx {
const char *line;
int idx;
int val; /* relative to line */
int vlen; /* relative to line+val */
};
#endif /* _TYPES_PROTO_HTTP_H */

View File

@ -433,6 +433,98 @@ int http_header_match2(const char *hdr, const char *end,
return val - hdr;
}
/* Find the end of the header value contained between <s> and <e>.
* See RFC2616, par 2.2 for more information. Note that it requires
* a valid header to return a valid result.
*/
const char *find_hdr_value_end(const char *s, const char *e)
{
int quoted, qdpair;
quoted = qdpair = 0;
for (; s < e; s++) {
if (qdpair) qdpair = 0;
else if (quoted && *s == '\\') qdpair = 1;
else if (quoted && *s == '"') quoted = 0;
else if (*s == '"') quoted = 1;
else if (*s == ',') return s;
}
return s;
}
/* Find the first or next occurrence of header <name> in message buffer <sol>
* using headers index <idx>, and return it in the <ctx> structure. This
* structure holds everything necessary to use the header and find next
* occurrence. If its <idx> member is 0, the header is searched from the
* beginning. Otherwise, the next occurrence is returned. The function returns
* 1 when it finds a value, and 0 when there is no more.
*/
int http_find_header2(const char *name, int len,
const char *sol, struct hdr_idx *idx,
struct hdr_ctx *ctx)
{
__label__ return_hdr, next_hdr;
const char *eol, *sov;
int cur_idx;
if (ctx->idx) {
/* We have previously returned a value, let's search
* another one on the same line.
*/
cur_idx = ctx->idx;
sol = ctx->line;
sov = sol + ctx->val + ctx->vlen;
eol = sol + idx->v[cur_idx].len;
if (sov >= eol)
/* no more values in this header */
goto next_hdr;
/* values remaining for this header, skip the comma */
sov++;
while (sov < eol && http_is_lws[(unsigned char)*sov])
sov++;
goto return_hdr;
}
/* first request for this header */
sol += hdr_idx_first_pos(idx);
cur_idx = hdr_idx_first_idx(idx);
while (cur_idx) {
eol = sol + idx->v[cur_idx].len;
if ((len < eol - sol) &&
(sol[len] == ':') &&
(strncasecmp(sol, name, len) == 0)) {
sov = sol + len + 1;
while (sov < eol && http_is_lws[(unsigned char)*sov])
sov++;
return_hdr:
ctx->line = sol;
ctx->idx = cur_idx;
ctx->val = sov - sol;
eol = find_hdr_value_end(sov, eol);
ctx->vlen = eol - sov;
return 1;
}
next_hdr:
sol = eol + idx->v[cur_idx].cr + 1;
cur_idx = idx->v[cur_idx].next;
}
return 0;
}
int http_find_header(const char *name,
const char *sol, struct hdr_idx *idx,
struct hdr_ctx *ctx)
{
return http_find_header2(name, strlen(name), sol, idx, ctx);
}
/*
* returns a message to the client ; the connection is shut down for read,
* and the request is cleared so that no server connection can be initiated.
@ -5285,6 +5377,86 @@ acl_fetch_url(struct proxy *px, struct session *l4, void *l7, int dir,
return 1;
}
/* 5. Check on HTTP header. A pointer to the beginning of the value is returned. */
static int
acl_fetch_hdr(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
struct http_txn *txn = l7;
struct hdr_idx *idx = &txn->hdr_idx;
struct hdr_ctx *ctx = (struct hdr_ctx *)test->ctx.a;
char *sol;
if (!(test->flags & ACL_TEST_F_FETCH_MORE))
/* search for header from the beginning */
ctx->idx = 0;
sol = (dir == ACL_DIR_REQ) ? txn->req.sol : txn->rsp.sol;
if (http_find_header2(expr->arg.str, expr->arg_len, sol, idx, ctx)) {
test->flags |= ACL_TEST_F_FETCH_MORE;
test->flags |= ACL_TEST_F_VOL_HDR;
test->len = ctx->vlen;
test->ptr = (char *)ctx->line + ctx->val;
return 1;
}
test->flags &= ~ACL_TEST_F_FETCH_MORE;
test->flags |= ACL_TEST_F_VOL_HDR;
return 0;
}
/* 6. Check on HTTP header count. The number of occurrences is returned. */
static int
acl_fetch_hdr_cnt(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
struct http_txn *txn = l7;
struct hdr_idx *idx = &txn->hdr_idx;
struct hdr_ctx ctx;
char *sol;
int cnt;
sol = (dir == ACL_DIR_REQ) ? txn->req.sol : txn->rsp.sol;
ctx.idx = 0;
cnt = 0;
while (http_find_header2(expr->arg.str, expr->arg_len, sol, idx, &ctx))
cnt++;
test->i = cnt;
test->flags = ACL_TEST_F_VOL_HDR;
return 1;
}
/* 7. Check on HTTP header's integer value. The integer value is returned.
* FIXME: the type is 'int', it may not be appropriate for everything.
*/
static int
acl_fetch_hdr_val(struct proxy *px, struct session *l4, void *l7, int dir,
struct acl_expr *expr, struct acl_test *test)
{
struct http_txn *txn = l7;
struct hdr_idx *idx = &txn->hdr_idx;
struct hdr_ctx *ctx = (struct hdr_ctx *)test->ctx.a;
char *sol;
if (!(test->flags & ACL_TEST_F_FETCH_MORE))
/* search for header from the beginning */
ctx->idx = 0;
sol = (dir == ACL_DIR_REQ) ? txn->req.sol : txn->rsp.sol;
if (http_find_header2(expr->arg.str, expr->arg_len, sol, idx, ctx)) {
test->flags |= ACL_TEST_F_FETCH_MORE;
test->flags |= ACL_TEST_F_VOL_HDR;
test->i = strl2ic((char *)ctx->line + ctx->val, ctx->vlen);
return 1;
}
test->flags &= ~ACL_TEST_F_FETCH_MORE;
test->flags |= ACL_TEST_F_VOL_HDR;
return 0;
}
/************************************************************************/
@ -5306,6 +5478,15 @@ static struct acl_kw_list acl_kws = {{ },{
{ "url_dom", acl_parse_str, acl_fetch_url, acl_match_dom },
{ "url_reg", acl_parse_reg, acl_fetch_url, acl_match_reg },
{ "hdr", acl_parse_str, acl_fetch_hdr, acl_match_str },
{ "hdr_reg", acl_parse_reg, acl_fetch_hdr, acl_match_reg },
{ "hdr_beg", acl_parse_str, acl_fetch_hdr, acl_match_beg },
{ "hdr_end", acl_parse_str, acl_fetch_hdr, acl_match_end },
{ "hdr_sub", acl_parse_str, acl_fetch_hdr, acl_match_sub },
{ "hdr_dir", acl_parse_str, acl_fetch_hdr, acl_match_dir },
{ "hdr_dom", acl_parse_str, acl_fetch_hdr, acl_match_dom },
{ "hdr_cnt", acl_parse_int, acl_fetch_hdr_cnt, acl_match_int },
{ "hdr_val", acl_parse_int, acl_fetch_hdr_val, acl_match_int },
{ NULL, NULL, NULL, NULL },
#if 0
@ -5325,15 +5506,6 @@ static struct acl_kw_list acl_kws = {{ },{
{ "path_dir", acl_parse_str, acl_fetch_path, acl_match_dir },
{ "path_dom", acl_parse_str, acl_fetch_path, acl_match_dom },
{ "hdr", acl_parse_str, acl_fetch_hdr, acl_match_str },
{ "hdr_reg", acl_parse_reg, acl_fetch_hdr, acl_match_reg },
{ "hdr_beg", acl_parse_str, acl_fetch_hdr, acl_match_beg },
{ "hdr_end", acl_parse_str, acl_fetch_hdr, acl_match_end },
{ "hdr_sub", acl_parse_str, acl_fetch_hdr, acl_match_sub },
{ "hdr_dir", acl_parse_str, acl_fetch_hdr, acl_match_dir },
{ "hdr_dom", acl_parse_str, acl_fetch_hdr, acl_match_dom },
{ "hdr_pst", acl_parse_none, acl_fetch_hdr, acl_match_pst },
{ "cook", acl_parse_str, acl_fetch_cook, acl_match_str },
{ "cook_reg", acl_parse_reg, acl_fetch_cook, acl_match_reg },
{ "cook_beg", acl_parse_str, acl_fetch_cook, acl_match_beg },