RepoMirrors/haproxy
1
0
Fork 0
mirror of http://git.haproxy.org/git/haproxy.git/ synced 2025-04-16 20:15:49 +00:00
Code Issues Packages Projects Releases Wiki Activity

[MEDIUM] http: add support for conditional response header rewriting

Browse Source 
Just as for the req* rules, we can now condition rsp* rules with ACLs.
ACLs match on response, so volatile request information cannot be used.
A warning is emitted if a configuration contains such an anomaly.
This commit is contained in:
Willy Tarreau 2010-01-31 15:43:27 +01:00
parent 8abd4cd526
commit fdb563c06f
4 changed files with 103 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
doc/configuration.txt
View File

@ -3857,7 +3857,7 @@ retries <value>
See also : "option redispatch"
rspadd <string>
rspadd <string> [{if | unless} <cond>]
Add a header at the end of the HTTP response
May be used in sections : defaults | frontend | listen | backend
no | yes | yes | yes
@ -3866,6 +3866,9 @@ rspadd <string>
must be escaped using a backslash ('\'). Please refer to section
6 about HTTP header manipulation for more information.
<cond> is an optional matching condition built from ACLs. It makes it
possible to ignore this rule when other conditions are not met.
A new line consisting in <string> followed by a line feed will be added after
the last header of an HTTP response.
@ -3873,11 +3876,12 @@ rspadd <string>
and not to traffic generated by HAProxy, such as health-checks or error
responses.
See also: "reqadd" and section 6 about HTTP header manipulation
See also: "reqadd", section 6 about HTTP header manipulation, and section 7
about ACLs.
rspdel <search>
rspidel <search> (ignore case)
rspdel <search> [{if | unless} <cond>]
rspidel <search> [{if | unless} <cond>] (ignore case)
Delete all headers matching a regular expression in an HTTP response
May be used in sections : defaults | frontend | listen | backend
no | yes | yes | yes
@ -3890,6 +3894,9 @@ rspidel <search> (ignore case)
The "rspdel" keyword strictly matches case while "rspidel"
ignores case.
<cond> is an optional matching condition built from ACLs. It makes it
possible to ignore this rule when other conditions are not met.
Any header line matching extended regular expression <search> in the response
will be completely deleted. Most common use of this is to remove unwanted
and/or sensible headers or cookies from a response before passing it to the
@ -3903,12 +3910,12 @@ rspidel <search> (ignore case)
# remove the Server header from responses
reqidel ^Server:.*
See also: "rspadd", "rsprep", "reqdel" and section 6 about HTTP header
manipulation
See also: "rspadd", "rsprep", "reqdel", section 6 about HTTP header
manipulation, and section 7 about ACLs.
rspdeny <search>
rspideny <search> (ignore case)
rspdeny <search> [{if | unless} <cond>]
rspideny <search> [{if | unless} <cond>] (ignore case)
Block an HTTP response if a line matches a regular expression
May be used in sections : defaults | frontend | listen | backend
no | yes | yes | yes
@ -3921,6 +3928,9 @@ rspideny <search> (ignore case)
The "rspdeny" keyword strictly matches case while "rspideny"
ignores case.
<cond> is an optional matching condition built from ACLs. It makes it
possible to ignore this rule when other conditions are not met.
A response containing any line which matches extended regular expression
<search> will mark the request as denied. The test applies both to the
response line and to response headers. Keep in mind that header names are not
@ -3938,12 +3948,12 @@ rspideny <search> (ignore case)
# Ensure that no content type matching ms-word will leak
rspideny ^Content-type:\.*/ms-word
See also: "reqdeny", "acl", "block" and section 6 about HTTP header
manipulation
See also: "reqdeny", "acl", "block", section 6 about HTTP header manipulation
and section 7 about ACLs.
rsprep <search> <string>
rspirep <search> <string> (ignore case)
rsprep <search> <string> [{if | unless} <cond>]
rspirep <search> <string> [{if | unless} <cond>] (ignore case)
Replace a regular expression with a string in an HTTP response line
May be used in sections : defaults | frontend | listen | backend
no | yes | yes | yes
@ -3962,6 +3972,9 @@ rspirep <search> <string> (ignore case)
being a single digit between 0 and 9. Please refer to section
6 about HTTP header manipulation for more information.
<cond> is an optional matching condition built from ACLs. It makes it
possible to ignore this rule when other conditions are not met.
Any line matching extended regular expression <search> in the response (both
the response line and header lines) will be completely replaced with
<string>. Most common use of this is to rewrite Location headers.
@ -3976,8 +3989,8 @@ rspirep <search> <string> (ignore case)
# replace "Location: 127.0.0.1:8080" with "Location: www.mydomain.com"
rspirep ^Location:\ 127.0.0.1:8080 Location:\ www.mydomain.com
See also: "rspadd", "rspdel", "reqrep" and section 6 about HTTP header
manipulation
See also: "rspadd", "rspdel", "reqrep", section 6 about HTTP header
manipulation, and section 7 about ACLs.
server <name> <address>[:port] [param*]

4
include/proto/proto_http.h
View File

@ -2,7 +2,7 @@
* include/proto/proto_http.h
* This file contains HTTP protocol definitions.
*
* Copyright (C) 2000-2009 Willy Tarreau - w@1wt.eu
* Copyright (C) 2000-2010 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@ -76,7 +76,7 @@ void get_srv_from_appsession(struct session *t, const char *begin, int len);
int apply_filter_to_req_headers(struct session *t, struct buffer *req, struct hdr_exp *exp);
int apply_filter_to_req_line(struct session *t, struct buffer *req, struct hdr_exp *exp);
int apply_filters_to_request(struct session *s, struct buffer *req, struct proxy *px);
int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_exp *exp);
int apply_filters_to_response(struct session *t, struct buffer *rtr, struct proxy *px);
void manage_client_side_appsession(struct session *t, const char *buf, int len);
void manage_client_side_cookies(struct session *t, struct buffer *req);
void manage_server_side_cookies(struct session *t, struct buffer *rtr);

48
src/cfgparse.c
View File

@ -405,6 +405,23 @@ static int warnif_cond_requires_resp(const struct acl_cond *cond, const char *fi
return ERR_WARN;
}
/* Report it if a request ACL condition uses some request-only volatile parameters.
* It returns either 0 or ERR_WARN so that its result can be or'ed with err_code.
* Note that <cond> may be NULL and then will be ignored.
*/
static int warnif_cond_requires_req(const struct acl_cond *cond, const char *file, int line)
{
struct acl *acl;
if (!cond || !(cond->requires & ACL_USE_REQ_VOLATILE))
return 0;
acl = cond_find_require(cond, ACL_USE_REQ_VOLATILE);
Warning("parsing [%s:%d] : acl '%s' involves some volatile request-only criteria which will be ignored.\n",
file, line, acl ? acl->name : "(unknown)");
return ERR_WARN;
}
/*
* parse a line in a <global> section. Returns the error code, 0 if OK, or
@ -947,6 +964,8 @@ static int create_cond_regex_rule(const char *file, int line,
if (dir == ACL_DIR_REQ)
err_code |= warnif_cond_requires_resp(cond, file, line);
else
err_code |= warnif_cond_requires_req(cond, file, line);
preg = calloc(1, sizeof(regex_t));
if (!preg) {
@ -3770,21 +3789,21 @@ stats_error_parsing:
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_REPLACE, 0,
args[0], args[1], args[2], NULL);
args[0], args[1], args[2], (const char **)args+3);
if (err_code & ERR_FATAL)
goto out;
}
else if (!strcmp(args[0], "rspdel")) { /* delete response header from a regex */
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_REMOVE, 0,
args[0], args[1], NULL, NULL);
args[0], args[1], NULL, (const char **)args+2);
if (err_code & ERR_FATAL)
goto out;
}
else if (!strcmp(args[0], "rspdeny")) { /* block response header from a regex */
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_DENY, 0,
args[0], args[1], NULL, NULL);
args[0], args[1], NULL, (const char **)args+2);
if (err_code & ERR_FATAL)
goto out;
}
@ -3798,21 +3817,21 @@ stats_error_parsing:
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_REPLACE, REG_ICASE,
args[0], args[1], args[2], NULL);
args[0], args[1], args[2], (const char **)args+3);
if (err_code & ERR_FATAL)
goto out;
}
else if (!strcmp(args[0], "rspidel")) { /* delete response header from a regex ignoring case */
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_REMOVE, REG_ICASE,
args[0], args[1], NULL, NULL);
args[0], args[1], NULL, (const char **)args+2);
if (err_code & ERR_FATAL)
goto out;
}
else if (!strcmp(args[0], "rspideny")) { /* block response header from a regex ignoring case */
err_code |= create_cond_regex_rule(file, linenum, curproxy,
ACL_DIR_RTR, ACT_DENY, REG_ICASE,
args[0], args[1], NULL, NULL);
args[0], args[1], NULL, (const char **)args+2);
if (err_code & ERR_FATAL)
goto out;
}
@ -3833,7 +3852,24 @@ stats_error_parsing:
goto out;
}
if ((strcmp(args[2], "if") == 0 || strcmp(args[2], "unless") == 0)) {
if ((cond = build_acl_cond(file, linenum, curproxy, (const char **)args+2)) == NULL) {
Alert("parsing [%s:%d] : error detected while parsing a '%s' condition.\n",
file, linenum, args[0]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
}
err_code |= warnif_cond_requires_req(cond, file, linenum);
}
else if (*args[2]) {
Alert("parsing [%s:%d] : '%s' : Expecting nothing, 'if', or 'unless', got '%s'.\n",
file, linenum, args[0], args[2]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
}
wl = calloc(1, sizeof(*wl));
wl->cond = cond;
wl->s = strdup(args[1]);
LIST_ADDQ(&curproxy->rsp_add, &wl->list);
}

41
src/proto_http.c
View File

@ -4582,7 +4582,7 @@ int http_process_res_common(struct session *t, struct buffer *rep, int an_bit, s
/* try headers filters */
if (rule_set->rsp_exp != NULL) {
if (apply_filters_to_response(t, rep, rule_set->rsp_exp) < 0) {
if (apply_filters_to_response(t, rep, rule_set) < 0) {
return_bad_resp:
if (t->srv) {
t->srv->counters.failed_resp++;
@ -4618,6 +4618,14 @@ int http_process_res_common(struct session *t, struct buffer *rep, int an_bit, s
list_for_each_entry(wl, &rule_set->rsp_add, list) {
if (txn->status < 200)
break;
if (wl->cond) {
int ret = acl_exec_cond(wl->cond, px, t, txn, ACL_DIR_RTR);
ret = acl_pass(ret);
if (((struct acl_cond *)wl->cond)->pol == ACL_COND_UNLESS)
ret = !ret;
if (!ret)
continue;
}
if (unlikely(http_header_add_tail(rep, &txn->rsp, &txn->hdr_idx, wl->s) < 0))
goto return_bad_resp;
}
@ -5806,15 +5814,16 @@ int apply_filter_to_sts_line(struct session *t, struct buffer *rtr, struct hdr_e
/*
* Apply all the resp filters <exp> to all headers in buffer <rtr> of session <t>.
* Apply all the resp filters of proxy <px> to all headers in buffer <rtr> of session <s>.
* Returns 0 if everything is alright, or -1 in case a replacement lead to an
* unparsable response.
*/
int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_exp *exp)
int apply_filters_to_response(struct session *s, struct buffer *rtr, struct proxy *px)
{
struct http_txn *txn = &t->txn;
/* iterate through the filters in the outer loop */
while (exp && !(txn->flags & TX_SVDENY)) {
struct http_txn *txn = &s->txn;
struct hdr_exp *exp;
for (exp = px->rsp_exp; exp; exp = exp->next) {
int ret;
/*
@ -5823,6 +5832,9 @@ int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_
* the evaluation.
*/
if (txn->flags & TX_SVDENY)
break;
if ((txn->flags & TX_SVALLOW) &&
(exp->action == ACT_ALLOW || exp->action == ACT_DENY ||
exp->action == ACT_PASS)) {
@ -5830,8 +5842,20 @@ int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_
continue;
}
/* if this filter had a condition, evaluate it now and skip to
* next filter if the condition does not match.
*/
if (exp->cond) {
ret = acl_exec_cond(exp->cond, px, s, txn, ACL_DIR_RTR);
ret = acl_pass(ret);
if (((struct acl_cond *)exp->cond)->pol == ACL_COND_UNLESS)
ret = !ret;
if (!ret)
continue;
}
/* Apply the filter to the status line. */
ret = apply_filter_to_sts_line(t, rtr, exp);
ret = apply_filter_to_sts_line(s, rtr, exp);
if (unlikely(ret < 0))
return -1;
@ -5839,9 +5863,8 @@ int apply_filters_to_response(struct session *t, struct buffer *rtr, struct hdr_
/* The filter did not match the response, it can be
* iterated through all headers.
*/
apply_filter_to_resp_headers(t, rtr, exp);
apply_filter_to_resp_headers(s, rtr, exp);
}
exp = exp->next;
}
return 0;
}