blob: 14845aad10beda995fd94e19ae1cc3677bb2f8c9 [file] [log] [blame]
/*
* HTTP actions
*
* Copyright 2000-2018 Willy Tarreau <w@1wt.eu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <sys/types.h>
#include <ctype.h>
#include <string.h>
#include <time.h>
#include <common/chunk.h>
#include <common/compat.h>
#include <common/config.h>
#include <common/debug.h>
#include <common/http.h>
#include <common/initcall.h>
#include <common/memory.h>
#include <common/standard.h>
#include <common/version.h>
#include <types/capture.h>
#include <types/global.h>
#include <proto/acl.h>
#include <proto/arg.h>
#include <proto/http_rules.h>
#include <proto/http_htx.h>
#include <proto/log.h>
#include <proto/proto_http.h>
#include <proto/stream_interface.h>
/* This function executes one of the set-{method,path,query,uri} actions. It
* builds a string in the trash from the specified format string. It finds
* the action to be performed in <http.action>, previously filled by function
* parse_set_req_line(). The replacement action is excuted by the function
* http_action_set_req_line(). It always returns ACT_RET_CONT. If an error
* occurs the action is canceled, but the rule processing continue.
*/
static enum act_return http_action_set_req_line(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct buffer *replace;
enum act_return ret = ACT_RET_ERR;
replace = alloc_trash_chunk();
if (!replace)
goto leave;
/* If we have to create a query string, prepare a '?'. */
if (rule->arg.http.action == 2)
replace->area[replace->data++] = '?';
replace->data += build_logline(s, replace->area + replace->data,
replace->size - replace->data,
&rule->arg.http.logfmt);
http_replace_req_line(rule->arg.http.action, replace->area,
replace->data, px, s);
ret = ACT_RET_CONT;
leave:
free_trash_chunk(replace);
return ret;
}
/* parse an http-request action among :
* set-method
* set-path
* set-query
* set-uri
*
* All of them accept a single argument of type string representing a log-format.
* The resulting rule makes use of arg->act.p[0..1] to store the log-format list
* head, and p[2] to store the action as an int (0=method, 1=path, 2=query, 3=uri).
* It returns ACT_RET_PRS_OK on success, ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_set_req_line(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
int cur_arg = *orig_arg;
rule->action = ACT_CUSTOM;
switch (args[0][4]) {
case 'm' :
rule->arg.http.action = 0;
rule->action_ptr = http_action_set_req_line;
break;
case 'p' :
rule->arg.http.action = 1;
rule->action_ptr = http_action_set_req_line;
break;
case 'q' :
rule->arg.http.action = 2;
rule->action_ptr = http_action_set_req_line;
break;
case 'u' :
rule->arg.http.action = 3;
rule->action_ptr = http_action_set_req_line;
break;
default:
memprintf(err, "internal error: unhandled action '%s'", args[0]);
return ACT_RET_PRS_ERR;
}
if (!*args[cur_arg] ||
(*args[cur_arg + 1] && strcmp(args[cur_arg + 1], "if") != 0 && strcmp(args[cur_arg + 1], "unless") != 0)) {
memprintf(err, "expects exactly 1 argument <format>");
return ACT_RET_PRS_ERR;
}
LIST_INIT(&rule->arg.http.logfmt);
px->conf.args.ctx = ARGC_HRQ;
if (!parse_logformat_string(args[cur_arg], px, &rule->arg.http.logfmt, LOG_OPT_HTTP,
(px->cap & PR_CAP_FE) ? SMP_VAL_FE_HRQ_HDR : SMP_VAL_BE_HRQ_HDR, err)) {
return ACT_RET_PRS_ERR;
}
(*orig_arg)++;
return ACT_RET_PRS_OK;
}
/* This function executes a replace-uri action. It finds its arguments in
* <rule>.arg.act.p[]. It builds a string in the trash from the format string
* previously filled by function parse_replace_uri() and will execute the regex
* in p[1] to replace the URI. It uses the format string present in act.p[2..3].
* The component to act on (path/uri) is taken from act.p[0] which contains 1
* for the path or 3 for the URI (values used by http_req_replace_stline()).
* It always returns ACT_RET_CONT. If an error occurs, the action is canceled,
* but the rule processing continues.
*/
static enum act_return http_action_replace_uri(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
enum act_return ret = ACT_RET_ERR;
struct buffer *replace, *output;
struct ist uri;
int len;
replace = alloc_trash_chunk();
output = alloc_trash_chunk();
if (!replace || !output)
goto leave;
if (IS_HTX_STRM(s))
uri = htx_sl_req_uri(http_get_stline(htxbuf(&s->req.buf)));
else
uri = ist2(ci_head(&s->req) + s->txn->req.sl.rq.u, s->txn->req.sl.rq.u_l);
if (rule->arg.act.p[0] == (void *)1)
uri = http_get_path(uri); // replace path
if (!regex_exec_match2(rule->arg.act.p[1], uri.ptr, uri.len, MAX_MATCH, pmatch, 0))
goto leave;
replace->data = build_logline(s, replace->area, replace->size, (struct list *)&rule->arg.act.p[2]);
/* note: uri.ptr doesn't need to be zero-terminated because it will
* only be used to pick pmatch references.
*/
len = exp_replace(output->area, output->size, uri.ptr, replace->area, pmatch);
if (len == -1)
goto leave;
http_replace_req_line((long)rule->arg.act.p[0], output->area, len, px, s);
ret = ACT_RET_CONT;
leave:
free_trash_chunk(output);
free_trash_chunk(replace);
return ret;
}
/* parse a "replace-uri" or "replace-path" http-request action.
* This action takes 2 arguments (a regex and a replacement format string).
* The resulting rule makes use of arg->act.p[0] to store the action (1/3 for now),
* p[1] to store the compiled regex, and arg->act.p[2..3] to store the log-format
* list head. It returns ACT_RET_PRS_OK on success, ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_replace_uri(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
int cur_arg = *orig_arg;
char *error = NULL;
rule->action = ACT_CUSTOM;
if (strcmp(args[cur_arg-1], "replace-path") == 0)
rule->arg.act.p[0] = (void *)1; // replace-path
else
rule->arg.act.p[0] = (void *)3; // replace-uri
rule->action_ptr = http_action_replace_uri;
if (!*args[cur_arg] || !*args[cur_arg+1] ||
(*args[cur_arg+2] && strcmp(args[cur_arg+2], "if") != 0 && strcmp(args[cur_arg+2], "unless") != 0)) {
memprintf(err, "expects exactly 2 arguments <match-regex> and <replace-format>");
return ACT_RET_PRS_ERR;
}
if (!(rule->arg.act.p[1] = regex_comp(args[cur_arg], 1, 1, &error))) {
memprintf(err, "failed to parse the regex : %s", error);
free(error);
return ACT_RET_PRS_ERR;
}
LIST_INIT((struct list *)&rule->arg.act.p[2]);
px->conf.args.ctx = ARGC_HRQ;
if (!parse_logformat_string(args[cur_arg + 1], px, (struct list *)&rule->arg.act.p[2], LOG_OPT_HTTP,
(px->cap & PR_CAP_FE) ? SMP_VAL_FE_HRQ_HDR : SMP_VAL_BE_HRQ_HDR, err)) {
return ACT_RET_PRS_ERR;
}
(*orig_arg) += 2;
return ACT_RET_PRS_OK;
}
/* This function is just a compliant action wrapper for "set-status". */
static enum act_return action_http_set_status(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
http_set_status(rule->arg.status.code, rule->arg.status.reason, s);
return ACT_RET_CONT;
}
/* parse set-status action:
* This action accepts a single argument of type int representing
* an http status code. It returns ACT_RET_PRS_OK on success,
* ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_http_set_status(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
char *error;
rule->action = ACT_CUSTOM;
rule->action_ptr = action_http_set_status;
/* Check if an argument is available */
if (!*args[*orig_arg]) {
memprintf(err, "expects 1 argument: <status>; or 3 arguments: <status> reason <fmt>");
return ACT_RET_PRS_ERR;
}
/* convert status code as integer */
rule->arg.status.code = strtol(args[*orig_arg], &error, 10);
if (*error != '\0' || rule->arg.status.code < 100 || rule->arg.status.code > 999) {
memprintf(err, "expects an integer status code between 100 and 999");
return ACT_RET_PRS_ERR;
}
(*orig_arg)++;
/* set custom reason string */
rule->arg.status.reason = NULL; // If null, we use the default reason for the status code.
if (*args[*orig_arg] && strcmp(args[*orig_arg], "reason") == 0 &&
(*args[*orig_arg + 1] && strcmp(args[*orig_arg + 1], "if") != 0 && strcmp(args[*orig_arg + 1], "unless") != 0)) {
(*orig_arg)++;
rule->arg.status.reason = strdup(args[*orig_arg]);
(*orig_arg)++;
}
return ACT_RET_PRS_OK;
}
/* This function executes the "reject" HTTP action. It clears the request and
* response buffer without sending any response. It can be useful as an HTTP
* alternative to the silent-drop action to defend against DoS attacks, and may
* also be used with HTTP/2 to close a connection instead of just a stream.
* The txn status is unchanged, indicating no response was sent. The termination
* flags will indicate "PR". It always returns ACT_RET_DONE.
*/
static enum act_return http_action_reject(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
si_must_kill_conn(chn_prod(&s->req));
channel_abort(&s->req);
channel_abort(&s->res);
s->req.analysers = 0;
s->res.analysers = 0;
_HA_ATOMIC_ADD(&s->be->be_counters.denied_req, 1);
_HA_ATOMIC_ADD(&sess->fe->fe_counters.denied_req, 1);
if (sess->listener && sess->listener->counters)
_HA_ATOMIC_ADD(&sess->listener->counters->denied_req, 1);
if (!(s->flags & SF_ERR_MASK))
s->flags |= SF_ERR_PRXCOND;
if (!(s->flags & SF_FINST_MASK))
s->flags |= SF_FINST_R;
return ACT_RET_DONE;
}
/* parse the "reject" action:
* This action takes no argument and returns ACT_RET_PRS_OK on success,
* ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_http_action_reject(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_reject;
return ACT_RET_PRS_OK;
}
/* This function executes the "disable-l7-retry" HTTP action.
* It disables L7 retries (all retry except for a connection failure). This
* can be useful for example to avoid retrying on POST requests.
* It just removes the L7 retry flag on the stream_interface, and always
* return ACT_RET_CONT;
*/
static enum act_return http_req_disable_l7_retry(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct stream_interface *si = &s->si[1];
/* In theory, the SI_FL_L7_RETRY flags isn't set at this point, but
* let's be future-proof and remove it anyway.
*/
si->flags &= ~SI_FL_L7_RETRY;
si->flags |= SI_FL_D_L7_RETRY;
return ACT_RET_CONT;
}
/* parse the "disable-l7-retry" action:
* This action takes no argument and returns ACT_RET_PRS_OK on success,
* ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_http_req_disable_l7_retry(const char **args,
int *orig_args, struct proxy *px,
struct act_rule *rule, char **err)
{
rule->action = ACT_CUSTOM;
rule->action_ptr = http_req_disable_l7_retry;
return ACT_RET_PRS_OK;
}
/* This function executes the "capture" action. It executes a fetch expression,
* turns the result into a string and puts it in a capture slot. It always
* returns 1. If an error occurs the action is cancelled, but the rule
* processing continues.
*/
static enum act_return http_action_req_capture(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct sample *key;
struct cap_hdr *h = rule->arg.cap.hdr;
char **cap = s->req_cap;
int len;
key = sample_fetch_as_type(s->be, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL, rule->arg.cap.expr, SMP_T_STR);
if (!key)
return ACT_RET_CONT;
if (cap[h->index] == NULL)
cap[h->index] = pool_alloc(h->pool);
if (cap[h->index] == NULL) /* no more capture memory */
return ACT_RET_CONT;
len = key->data.u.str.data;
if (len > h->len)
len = h->len;
memcpy(cap[h->index], key->data.u.str.area, len);
cap[h->index][len] = 0;
return ACT_RET_CONT;
}
/* This function executes the "capture" action and store the result in a
* capture slot if exists. It executes a fetch expression, turns the result
* into a string and puts it in a capture slot. It always returns 1. If an
* error occurs the action is cancelled, but the rule processing continues.
*/
static enum act_return http_action_req_capture_by_id(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct sample *key;
struct cap_hdr *h;
char **cap = s->req_cap;
struct proxy *fe = strm_fe(s);
int len;
int i;
/* Look for the original configuration. */
for (h = fe->req_cap, i = fe->nb_req_cap - 1;
h != NULL && i != rule->arg.capid.idx ;
i--, h = h->next);
if (!h)
return ACT_RET_CONT;
key = sample_fetch_as_type(s->be, sess, s, SMP_OPT_DIR_REQ|SMP_OPT_FINAL, rule->arg.capid.expr, SMP_T_STR);
if (!key)
return ACT_RET_CONT;
if (cap[h->index] == NULL)
cap[h->index] = pool_alloc(h->pool);
if (cap[h->index] == NULL) /* no more capture memory */
return ACT_RET_CONT;
len = key->data.u.str.data;
if (len > h->len)
len = h->len;
memcpy(cap[h->index], key->data.u.str.area, len);
cap[h->index][len] = 0;
return ACT_RET_CONT;
}
/* Check an "http-request capture" action.
*
* The function returns 1 in success case, otherwise, it returns 0 and err is
* filled.
*/
static int check_http_req_capture(struct act_rule *rule, struct proxy *px, char **err)
{
if (rule->action_ptr != http_action_req_capture_by_id)
return 1;
/* capture slots can only be declared in frontends, so we can't check their
* existence in backends at configuration parsing step
*/
if (px->cap & PR_CAP_FE && rule->arg.capid.idx >= px->nb_req_cap) {
memprintf(err, "unable to find capture id '%d' referenced by http-request capture rule",
rule->arg.capid.idx);
return 0;
}
return 1;
}
/* parse an "http-request capture" action. It takes a single argument which is
* a sample fetch expression. It stores the expression into arg->act.p[0] and
* the allocated hdr_cap struct or the preallocated "id" into arg->act.p[1].
* It returns ACT_RET_PRS_OK on success, ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_http_req_capture(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
struct sample_expr *expr;
struct cap_hdr *hdr;
int cur_arg;
int len = 0;
for (cur_arg = *orig_arg; cur_arg < *orig_arg + 3 && *args[cur_arg]; cur_arg++)
if (strcmp(args[cur_arg], "if") == 0 ||
strcmp(args[cur_arg], "unless") == 0)
break;
if (cur_arg < *orig_arg + 3) {
memprintf(err, "expects <expression> [ 'len' <length> | id <idx> ]");
return ACT_RET_PRS_ERR;
}
cur_arg = *orig_arg;
expr = sample_parse_expr((char **)args, &cur_arg, px->conf.args.file, px->conf.args.line, err, &px->conf.args);
if (!expr)
return ACT_RET_PRS_ERR;
if (!(expr->fetch->val & SMP_VAL_FE_HRQ_HDR)) {
memprintf(err,
"fetch method '%s' extracts information from '%s', none of which is available here",
args[cur_arg-1], sample_src_names(expr->fetch->use));
free(expr);
return ACT_RET_PRS_ERR;
}
if (!args[cur_arg] || !*args[cur_arg]) {
memprintf(err, "expects 'len or 'id'");
free(expr);
return ACT_RET_PRS_ERR;
}
if (strcmp(args[cur_arg], "len") == 0) {
cur_arg++;
if (!(px->cap & PR_CAP_FE)) {
memprintf(err, "proxy '%s' has no frontend capability", px->id);
return ACT_RET_PRS_ERR;
}
px->conf.args.ctx = ARGC_CAP;
if (!args[cur_arg]) {
memprintf(err, "missing length value");
free(expr);
return ACT_RET_PRS_ERR;
}
/* we copy the table name for now, it will be resolved later */
len = atoi(args[cur_arg]);
if (len <= 0) {
memprintf(err, "length must be > 0");
free(expr);
return ACT_RET_PRS_ERR;
}
cur_arg++;
hdr = calloc(1, sizeof(*hdr));
hdr->next = px->req_cap;
hdr->name = NULL; /* not a header capture */
hdr->namelen = 0;
hdr->len = len;
hdr->pool = create_pool("caphdr", hdr->len + 1, MEM_F_SHARED);
hdr->index = px->nb_req_cap++;
px->req_cap = hdr;
px->to_log |= LW_REQHDR;
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_req_capture;
rule->arg.cap.expr = expr;
rule->arg.cap.hdr = hdr;
}
else if (strcmp(args[cur_arg], "id") == 0) {
int id;
char *error;
cur_arg++;
if (!args[cur_arg]) {
memprintf(err, "missing id value");
free(expr);
return ACT_RET_PRS_ERR;
}
id = strtol(args[cur_arg], &error, 10);
if (*error != '\0') {
memprintf(err, "cannot parse id '%s'", args[cur_arg]);
free(expr);
return ACT_RET_PRS_ERR;
}
cur_arg++;
px->conf.args.ctx = ARGC_CAP;
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_req_capture_by_id;
rule->check_ptr = check_http_req_capture;
rule->arg.capid.expr = expr;
rule->arg.capid.idx = id;
}
else {
memprintf(err, "expects 'len' or 'id', found '%s'", args[cur_arg]);
free(expr);
return ACT_RET_PRS_ERR;
}
*orig_arg = cur_arg;
return ACT_RET_PRS_OK;
}
/* This function executes the "capture" action and store the result in a
* capture slot if exists. It executes a fetch expression, turns the result
* into a string and puts it in a capture slot. It always returns 1. If an
* error occurs the action is cancelled, but the rule processing continues.
*/
static enum act_return http_action_res_capture_by_id(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct sample *key;
struct cap_hdr *h;
char **cap = s->res_cap;
struct proxy *fe = strm_fe(s);
int len;
int i;
/* Look for the original configuration. */
for (h = fe->rsp_cap, i = fe->nb_rsp_cap - 1;
h != NULL && i != rule->arg.capid.idx ;
i--, h = h->next);
if (!h)
return ACT_RET_CONT;
key = sample_fetch_as_type(s->be, sess, s, SMP_OPT_DIR_RES|SMP_OPT_FINAL, rule->arg.capid.expr, SMP_T_STR);
if (!key)
return ACT_RET_CONT;
if (cap[h->index] == NULL)
cap[h->index] = pool_alloc(h->pool);
if (cap[h->index] == NULL) /* no more capture memory */
return ACT_RET_CONT;
len = key->data.u.str.data;
if (len > h->len)
len = h->len;
memcpy(cap[h->index], key->data.u.str.area, len);
cap[h->index][len] = 0;
return ACT_RET_CONT;
}
/* Check an "http-response capture" action.
*
* The function returns 1 in success case, otherwise, it returns 0 and err is
* filled.
*/
static int check_http_res_capture(struct act_rule *rule, struct proxy *px, char **err)
{
if (rule->action_ptr != http_action_res_capture_by_id)
return 1;
if (rule->arg.capid.idx >= px->nb_rsp_cap) {
memprintf(err, "unable to find capture id '%d' referenced by http-response capture rule",
rule->arg.capid.idx);
return 0;
}
return 1;
}
/* parse an "http-response capture" action. It takes a single argument which is
* a sample fetch expression. It stores the expression into arg->act.p[0] and
* the allocated hdr_cap struct od the preallocated id into arg->act.p[1].
* It returns ACT_RET_PRS_OK on success, ACT_RET_PRS_ERR on error.
*/
static enum act_parse_ret parse_http_res_capture(const char **args, int *orig_arg, struct proxy *px,
struct act_rule *rule, char **err)
{
struct sample_expr *expr;
int cur_arg;
int id;
char *error;
for (cur_arg = *orig_arg; cur_arg < *orig_arg + 3 && *args[cur_arg]; cur_arg++)
if (strcmp(args[cur_arg], "if") == 0 ||
strcmp(args[cur_arg], "unless") == 0)
break;
if (cur_arg < *orig_arg + 3) {
memprintf(err, "expects <expression> id <idx>");
return ACT_RET_PRS_ERR;
}
cur_arg = *orig_arg;
expr = sample_parse_expr((char **)args, &cur_arg, px->conf.args.file, px->conf.args.line, err, &px->conf.args);
if (!expr)
return ACT_RET_PRS_ERR;
if (!(expr->fetch->val & SMP_VAL_FE_HRS_HDR)) {
memprintf(err,
"fetch method '%s' extracts information from '%s', none of which is available here",
args[cur_arg-1], sample_src_names(expr->fetch->use));
free(expr);
return ACT_RET_PRS_ERR;
}
if (!args[cur_arg] || !*args[cur_arg]) {
memprintf(err, "expects 'id'");
free(expr);
return ACT_RET_PRS_ERR;
}
if (strcmp(args[cur_arg], "id") != 0) {
memprintf(err, "expects 'id', found '%s'", args[cur_arg]);
free(expr);
return ACT_RET_PRS_ERR;
}
cur_arg++;
if (!args[cur_arg]) {
memprintf(err, "missing id value");
free(expr);
return ACT_RET_PRS_ERR;
}
id = strtol(args[cur_arg], &error, 10);
if (*error != '\0') {
memprintf(err, "cannot parse id '%s'", args[cur_arg]);
free(expr);
return ACT_RET_PRS_ERR;
}
cur_arg++;
px->conf.args.ctx = ARGC_CAP;
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_res_capture_by_id;
rule->check_ptr = check_http_res_capture;
rule->arg.capid.expr = expr;
rule->arg.capid.idx = id;
*orig_arg = cur_arg;
return ACT_RET_PRS_OK;
}
/************************************************************************/
/* All supported http-request action keywords must be declared here. */
/************************************************************************/
static struct action_kw_list http_req_actions = {
.kw = {
{ "capture", parse_http_req_capture },
{ "reject", parse_http_action_reject },
{ "disable-l7-retry", parse_http_req_disable_l7_retry },
{ "replace-path", parse_replace_uri },
{ "replace-uri", parse_replace_uri },
{ "set-method", parse_set_req_line },
{ "set-path", parse_set_req_line },
{ "set-query", parse_set_req_line },
{ "set-uri", parse_set_req_line },
{ NULL, NULL }
}
};
INITCALL1(STG_REGISTER, http_req_keywords_register, &http_req_actions);
static struct action_kw_list http_res_actions = {
.kw = {
{ "capture", parse_http_res_capture },
{ "set-status", parse_http_set_status },
{ NULL, NULL }
}
};
INITCALL1(STG_REGISTER, http_res_keywords_register, &http_res_actions);
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/