blob: 15e221012d3d03b66f30a26fc1b5591d63c0c372 [file] [log] [blame]
/*
* Cache management
*
* Copyright 2017 HAProxy Technologies
* William Lallemand <wlallemand@haproxy.com>
*
* 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 <eb32tree.h>
#include <proto/channel.h>
#include <proto/proxy.h>
#include <proto/hdr_idx.h>
#include <proto/filters.h>
#include <proto/proto_http.h>
#include <proto/log.h>
#include <proto/stream.h>
#include <proto/stream_interface.h>
#include <proto/shctx.h>
#include <types/action.h>
#include <types/filters.h>
#include <types/proxy.h>
#include <types/shctx.h>
#include <common/cfgparse.h>
#include <common/hash.h>
/* flt_cache_store */
static const char *cache_store_flt_id = "cache store filter";
static struct pool_head *pool2_cache_st = NULL;
struct applet http_cache_applet;
struct flt_ops cache_ops;
struct cache {
char id[33]; /* cache name */
unsigned int maxage; /* max-age */
unsigned int maxblocks;
struct list list; /* cache linked list */
struct eb_root entries; /* head of cache entries based on keys */
};
/*
* cache ctx for filters
*/
struct cache_st {
int hdrs_len;
struct shared_block *first_block;
};
struct cache_entry {
unsigned int latest_validation; /* latest validation date */
unsigned int expire; /* expiration date */
struct eb32_node eb; /* ebtree node used to hold the cache object */
unsigned char data[0];
};
#define CACHE_BLOCKSIZE 1024
static struct list caches = LIST_HEAD_INIT(caches);
static struct cache *tmp_cache_config = NULL;
struct cache_entry *entry_exist(struct cache *cache, struct cache_entry *new_entry)
{
struct eb32_node *node;
struct cache_entry *entry;
node = eb32_lookup(&cache->entries, new_entry->eb.key);
if (!node)
return NULL;
entry = eb32_entry(node, struct cache_entry, eb);
if (entry->expire > now.tv_sec)
return entry;
else
eb32_delete(node);
return NULL;
}
static inline struct shared_context *shctx_ptr(struct cache *cache)
{
return (struct shared_context *)((unsigned char *)cache - ((struct shared_context *)NULL)->data);
}
static inline struct shared_block *block_ptr(struct cache_entry *entry)
{
return (struct shared_block *)((unsigned char *)entry - ((struct shared_block *)NULL)->data);
}
static int
cache_store_init(struct proxy *px, struct flt_conf *f1conf)
{
return 0;
}
static int
cache_store_chn_start_analyze(struct stream *s, struct filter *filter, struct channel *chn)
{
if (!(chn->flags & CF_ISRESP))
return 1;
if (filter->ctx == NULL) {
struct cache_st *st;
st = pool_alloc_dirty(pool2_cache_st);
if (st == NULL)
return -1;
st->hdrs_len = 0;
st->first_block = NULL;
filter->ctx = st;
}
register_data_filter(s, chn, filter);
return 1;
}
static int
cache_store_http_headers(struct stream *s, struct filter *filter, struct http_msg *msg)
{
struct cache_st *st = filter->ctx;
/* end of headers, exclude the final \r\n allow to forward the final
* \r\n in the data filter */
if (!(msg->chn->flags & CF_ISRESP) || !st)
return 1;
st->hdrs_len = msg->eoh;
return 1;
}
static int
cache_store_http_forward_data(struct stream *s, struct filter *filter,
struct http_msg *msg, unsigned int len)
{
struct cache_st *st = filter->ctx;
struct shared_context *shctx = shctx_ptr((struct cache *)filter->config->conf);
int ret;
/*
* We need to skip the HTTP headers first, because we saved them in the
* http-response action.
*/
if (!(msg->chn->flags & CF_ISRESP) || !st)
return len;
if (!len) {
/* Nothing to foward */
ret = len;
}
else if (st->hdrs_len > len) {
/* Forward part of headers */
ret = len;
st->hdrs_len -= len;
}
else if (st->hdrs_len > 0) {
/* Forward remaining headers */
ret = st->hdrs_len;
st->hdrs_len = 0;
}
else {
/* Forward trailers data */
if (filter->ctx && st->first_block) {
/* disable buffering if too much data (never greater than a buffer size */
if (len > global.tune.bufsize - global.tune.maxrewrite - st->first_block->len) {
filter->ctx = NULL; /* disable cache */
shctx_lock(shctx);
shctx_row_dec_hot(shctx, st->first_block);
shctx_unlock(shctx);
pool_free2(pool2_cache_st, st);
ret = 0;
} else {
int blen;
blen = shctx_row_data_append(shctx,
st->first_block,
(unsigned char *)bi_ptr(msg->chn->buf),
MIN(bi_contig_data(msg->chn->buf), len));
ret = MIN(bi_contig_data(msg->chn->buf), len) + blen;
}
} else {
ret = len;
}
}
if ((ret != len) ||
(FLT_NXT(filter, msg->chn) != FLT_FWD(filter, msg->chn) + ret))
task_wakeup(s->task, TASK_WOKEN_MSG);
return ret;
}
static int
cache_store_http_end(struct stream *s, struct filter *filter,
struct http_msg *msg)
{
struct cache_st *st = filter->ctx;
struct cache *cache = filter->config->conf;
struct shared_context *shctx = shctx_ptr(cache);
struct cache_entry *object;
if (!(msg->chn->flags & CF_ISRESP))
return 1;
if (st && st->first_block) {
object = (struct cache_entry *)st->first_block->data;
/* does not need to test if the insertion worked, if it
* doesn't, the blocks will be reused anyway */
shctx_lock(shctx);
eb32_insert(&cache->entries, &object->eb);
shctx_unlock(shctx);
/* remove from the hotlist */
shctx_lock(shctx);
shctx_row_dec_hot(shctx, st->first_block);
shctx_unlock(shctx);
}
if (st) {
pool_free2(pool2_cache_st, st);
filter->ctx = NULL;
}
return 1;
}
/*
* This intends to be used when checking HTTP headers for some
* word=value directive. Return a pointer to the first character of value, if
* the word was not found or if there wasn't any value assigned ot it return NULL
*/
char *directive_value(const char *sample, int slen, const char *word, int wlen)
{
int st = 0;
if (slen < wlen)
return 0;
while (wlen) {
char c = *sample ^ *word;
if (c && c != ('A' ^ 'a'))
return NULL;
sample++;
word++;
slen--;
wlen--;
}
while (slen) {
if (st == 0) {
if (*sample != '=')
return NULL;
sample++;
slen--;
st = 1;
continue;
} else {
return (char *)sample;
}
}
return NULL;
}
/*
* Return the maxage in seconds of an HTTP response.
* Compute the maxage using either:
* - the assigned max-age of the cache
* - the s-maxage directive
* - the max-age directive
* - (Expires - Data) headers
* - the default-max-age of the cache
*
*/
int http_calc_maxage(struct stream *s)
{
struct http_txn *txn = s->txn;
struct hdr_ctx ctx;
int smaxage = -1;
int maxage = -1;
/* TODO: forced maxage configuration */
ctx.idx = 0;
/* loop on the Cache-Control values */
while (http_find_header2("Cache-Control", 13, s->res.buf->p, &txn->hdr_idx, &ctx)) {
char *directive = ctx.line + ctx.val;
char *value;
value = directive_value(directive, ctx.vlen, "s-maxage", 8);
if (value) {
struct chunk *chk = get_trash_chunk();
chunk_strncat(chk, value, ctx.vlen - 8 + 1);
chunk_strncat(chk, "", 1);
maxage = atoi(chk->str);
}
value = directive_value(ctx.line + ctx.val, ctx.vlen, "max-age", 7);
if (value) {
struct chunk *chk = get_trash_chunk();
chunk_strncat(chk, value, ctx.vlen - 7 + 1);
chunk_strncat(chk, "", 1);
smaxage = atoi(chk->str);
}
}
/* TODO: Expires - Data */
if (smaxage > 0)
return smaxage;
if (maxage > 0)
return maxage;
/* TODO: return default value */
return 60;
}
/*
* This fonction will store the headers of the response in a buffer and then
* register a filter to store the data
*/
enum act_return http_action_store_cache(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct http_txn *txn = s->txn;
struct http_msg *msg = &txn->rsp;
struct filter *filter;
struct hdr_ctx ctx;
struct shared_block *first = NULL;
struct shared_context *shctx = shctx_ptr((struct cache *)rule->arg.act.p[0]);
struct cache_entry *object;
/* Don't cache if the response came from a cache */
if ((obj_type(s->target) == OBJ_TYPE_APPLET) &&
s->target == &http_cache_applet.obj_type) {
goto out;
}
/* cache only HTTP/1.1 */
if (!(txn->req.flags & HTTP_MSGF_VER_11))
goto out;
/* cache only GET method */
if (txn->meth != HTTP_METH_GET)
goto out;
/* cache only 200 status code */
if (txn->status != 200)
goto out;
/* Does not manage Vary at the moment. We will need a secondary key later for that */
ctx.idx = 0;
if (http_find_header2("Vary", 4, txn->rsp.chn->buf->p, &txn->hdr_idx, &ctx))
goto out;
/* we need to put this flag before using check_response_for_cacheability */
txn->flags |= TX_CACHEABLE;
if (txn->status != 101)
check_response_for_cacheability(s, &s->res);
if (!(txn->flags & TX_CACHEABLE))
goto out;
if ((msg->eoh + msg->body_len) > (global.tune.bufsize - global.tune.maxrewrite))
goto out;
shctx_lock(shctx);
first = shctx_row_reserve_hot(shctx, sizeof(struct cache_entry) + msg->eoh + msg->body_len);
if (!first) {
shctx_unlock(shctx);
goto out;
}
shctx_unlock(shctx);
/* reserve space for the cache_entry structure */
first->len = sizeof(struct cache_entry);
/* cache the headers in a http action because it allows to chose what
* to cache, for example you might want to cache a response before
* modifying some HTTP headers, or on the contrary after modifying
* those headers.
*/
/* does not need to be locked because it's in the "hot" list,
* copy the headers */
if (shctx_row_data_append(shctx, first, (unsigned char *)s->res.buf->p, msg->eoh) < 0)
goto out;
/* register the buffer in the filter ctx for filling it with data*/
if (!LIST_ISEMPTY(&s->strm_flt.filters)) {
list_for_each_entry(filter, &s->strm_flt.filters, list) {
if (filter->config->id == cache_store_flt_id &&
filter->config->conf == rule->arg.act.p[0]) {
if (filter->ctx) {
struct cache_st *cache_ctx = filter->ctx;
cache_ctx->first_block = first;
object = (struct cache_entry *)first->data;
object->eb.key = hash_djb2(txn->uri, strlen(txn->uri));
/* Insert the node later on caching success */
shctx_lock(shctx);
if (entry_exist((struct cache *)rule->arg.act.p[0], object)) {
shctx_unlock(shctx);
if (filter->ctx) {
pool_free2(pool2_cache_st, filter->ctx);
filter->ctx = NULL;
}
goto out;
}
shctx_unlock(shctx);
/* store latest value and expiration time */
object->latest_validation = now.tv_sec;
object->expire = now.tv_sec + http_calc_maxage(s);
}
return ACT_RET_CONT;
}
}
}
out:
/* if does not cache */
if (first) {
shctx_lock(shctx);
shctx_row_dec_hot(shctx, first);
shctx_unlock(shctx);
}
return ACT_RET_CONT;
}
#define HTTP_CACHE_INIT 0
#define HTTP_CACHE_FWD 1
#define HTTP_CACHE_END 2
static void http_cache_io_handler(struct appctx *appctx)
{
struct stream_interface *si = appctx->owner;
struct channel *res = si_ic(si);
struct cache *cache = (struct cache *)appctx->rule->arg.act.p[0];
struct cache_entry *cache_ptr = appctx->ctx.cache.entry;
struct shared_context *shctx = shctx_ptr(cache);
struct shared_block *first = block_ptr(cache_ptr);
if (unlikely(si->state == SI_ST_DIS || si->state == SI_ST_CLO))
goto out;
/* Check if the input buffer is avalaible. */
if (res->buf->size == 0) {
si_applet_cant_put(si);
goto out;
}
if (res->flags & (CF_SHUTW|CF_SHUTW_NOW))
appctx->st0 = HTTP_CACHE_END;
/* buffer are aligned there, should be fine */
if (appctx->st0 == HTTP_CACHE_INIT) {
int len = first->len - sizeof(struct cache_entry);
if ((shctx_row_data_get(shctx, first, (unsigned char *)bi_end(res->buf), sizeof(struct cache_entry), len)) != 0) {
fprintf(stderr, "cache error too big: %d\n", first->len - (int)sizeof(struct cache_entry));
si_applet_cant_put(si);
goto out;
}
res->buf->i += len;
res->total += len;
appctx->st0 = HTTP_CACHE_FWD;
}
if (appctx->st0 == HTTP_CACHE_FWD) {
/* eat the whole request */
co_skip(si_oc(si), si_ob(si)->o); // NOTE: when disabled does not repport the correct status code
res->flags |= CF_READ_NULL;
si_shutr(si);
}
if ((res->flags & CF_SHUTR) && (si->state == SI_ST_EST))
si_shutw(si);
out:
;
}
enum act_parse_ret parse_cache_store(const char **args, int *orig_arg, struct proxy *proxy,
struct act_rule *rule, char **err)
{
struct flt_conf *fconf;
int cur_arg = *orig_arg;
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_store_cache;
if (!*args[cur_arg] || strcmp(args[cur_arg], "if") == 0 || strcmp(args[cur_arg], "unless") == 0) {
memprintf(err, "expects a cache name");
return ACT_RET_PRS_ERR;
}
/* check if a cache filter was already registered with this cache
* name, if that's the case, must use it. */
list_for_each_entry(fconf, &proxy->filter_configs, list) {
if (fconf->id == cache_store_flt_id && !strcmp((char *)fconf->conf, args[cur_arg])) {
rule->arg.act.p[0] = fconf->conf;
(*orig_arg)++;
/* filter already registered */
return ACT_RET_PRS_OK;
}
}
rule->arg.act.p[0] = strdup(args[cur_arg]);
if (!rule->arg.act.p[0]) {
Alert("config: %s '%s': out of memory\n", proxy_type_str(proxy), proxy->id);
err++;
goto err;
}
/* register a filter to fill the cache buffer */
fconf = calloc(1, sizeof(*fconf));
if (!fconf) {
Alert("config: %s '%s': out of memory\n",
proxy_type_str(proxy), proxy->id);
err++;
goto err;
}
fconf->id = cache_store_flt_id;
fconf->conf = rule->arg.act.p[0]; /* store the proxy name */
fconf->ops = &cache_ops;
LIST_ADDQ(&proxy->filter_configs, &fconf->list);
(*orig_arg)++;
return ACT_RET_PRS_OK;
err:
return ACT_RET_PRS_ERR;
}
enum act_return http_action_req_cache_use(struct act_rule *rule, struct proxy *px,
struct session *sess, struct stream *s, int flags)
{
struct cache_entry search_entry;
struct cache_entry *res;
struct cache *cache = (struct cache *)rule->arg.act.p[0];
search_entry.eb.key = hash_djb2(s->txn->uri, strlen(s->txn->uri));
res = entry_exist(cache, &search_entry);
if (res) {
struct appctx *appctx;
s->target = &http_cache_applet.obj_type;
if ((appctx = stream_int_register_handler(&s->si[1], objt_applet(s->target)))) {
appctx->st0 = HTTP_CACHE_INIT;
appctx->rule = rule;
appctx->ctx.cache.entry = res;
return ACT_RET_CONT;
} else {
return ACT_RET_YIELD;
}
}
return ACT_RET_CONT;
}
enum act_parse_ret parse_cache_use(const char **args, int *orig_arg, struct proxy *proxy,
struct act_rule *rule, char **err)
{
int cur_arg = *orig_arg;
rule->action = ACT_CUSTOM;
rule->action_ptr = http_action_req_cache_use;
if (!*args[cur_arg] || strcmp(args[cur_arg], "if") == 0 || strcmp(args[cur_arg], "unless") == 0) {
memprintf(err, "expects a cache name");
return ACT_RET_PRS_ERR;
}
rule->arg.act.p[0] = strdup(args[cur_arg]);
if (!rule->arg.act.p[0]) {
Alert("config: %s '%s': out of memory\n", proxy_type_str(proxy), proxy->id);
err++;
goto err;
}
(*orig_arg)++;
return ACT_RET_PRS_OK;
err:
return ACT_RET_PRS_ERR;
}
int cfg_parse_cache(const char *file, int linenum, char **args, int kwm)
{
int err_code = 0;
if (strcmp(args[0], "cache") == 0) { /* new cache section */
if (!*args[1]) {
Alert("parsing [%s:%d] : '%s' expects an <id> argument\n",
file, linenum, args[0]);
err_code |= ERR_ALERT | ERR_ABORT;
goto out;
}
if (alertif_too_many_args(1, file, linenum, args, &err_code)) {
err_code |= ERR_ABORT;
goto out;
}
if (tmp_cache_config == NULL) {
tmp_cache_config = calloc(1, sizeof(*tmp_cache_config));
if (!tmp_cache_config) {
Alert("parsing [%s:%d]: out of memory.\n", file, linenum);
err_code |= ERR_ALERT | ERR_ABORT;
goto out;
}
strlcpy2(tmp_cache_config->id, args[1], 33);
if (strlen(args[1]) > 32) {
Warning("parsing [%s:%d]: cache id is limited to 32 characters, truncate to '%s'.\n",
file, linenum, tmp_cache_config->id);
err_code |= ERR_WARN;
}
tmp_cache_config->maxblocks = 0;
}
} else if (strcmp(args[0], "total-max-size") == 0) {
int maxsize;
if (alertif_too_many_args(1, file, linenum, args, &err_code)) {
err_code |= ERR_ABORT;
goto out;
}
/* size in megabytes */
maxsize = atoi(args[1]) * 1024 * 1024 / CACHE_BLOCKSIZE;
tmp_cache_config->maxblocks = maxsize;
} else if (*args[0] != 0) {
Alert("parsing [%s:%d] : unknown keyword '%s' in 'cache' section\n", file, linenum, args[0]);
err_code |= ERR_ALERT | ERR_FATAL;
goto out;
}
out:
return err_code;
}
/* once the cache section is parsed */
int cfg_post_parse_section_cache()
{
struct shared_context *shctx;
int err_code = 0;
int ret_shctx;
if (tmp_cache_config) {
struct cache *cache;
if (tmp_cache_config->maxblocks <= 0) {
Alert("Size not specified for cache '%s'\n", tmp_cache_config->id);
err_code |= ERR_FATAL | ERR_ALERT;
goto out;
}
ret_shctx = shctx_init(&shctx, tmp_cache_config->maxblocks, CACHE_BLOCKSIZE, sizeof(struct cache), 1);
if (ret_shctx < 0) {
if (ret_shctx == SHCTX_E_INIT_LOCK)
Alert("Unable to initialize the lock for the cache.\n");
else
Alert("Unable to allocate cache.\n");
err_code |= ERR_FATAL | ERR_ALERT;
goto out;
}
memcpy(shctx->data, tmp_cache_config, sizeof(struct cache));
cache = (struct cache *)shctx->data;
cache->entries = EB_ROOT_UNIQUE;
LIST_ADDQ(&caches, &cache->list);
}
out:
free(tmp_cache_config);
tmp_cache_config = NULL;
return err_code;
}
/*
* Resolve the cache name to a pointer once the file is completely read.
*/
int cfg_cache_postparser()
{
struct act_rule *hresrule, *hrqrule;
void *cache_ptr;
struct cache *cache;
struct proxy *curproxy = NULL;
int err = 0;
struct flt_conf *fconf;
for (curproxy = proxy; curproxy; curproxy = curproxy->next) {
/* resolve the http response cache name to a ptr in the action rule */
list_for_each_entry(hresrule, &curproxy->http_res_rules, list) {
if (hresrule->action != ACT_CUSTOM ||
hresrule->action_ptr != http_action_store_cache)
continue;
cache_ptr = hresrule->arg.act.p[0];
list_for_each_entry(cache, &caches, list) {
if (!strcmp(cache->id, cache_ptr)) {
/* don't free there, it's still used in the filter conf */
cache_ptr = cache;
break;
}
}
if (cache_ptr == hresrule->arg.act.p[0]) {
Alert("Proxy '%s': unable to find the cache '%s' referenced by http-response cache-store rule.\n",
curproxy->id, (char *)hresrule->arg.act.p[0]);
err++;
}
hresrule->arg.act.p[0] = cache_ptr;
}
/* resolve the http request cache name to a ptr in the action rule */
list_for_each_entry(hrqrule, &curproxy->http_req_rules, list) {
if (hrqrule->action != ACT_CUSTOM ||
hrqrule->action_ptr != http_action_req_cache_use)
continue;
cache_ptr = hrqrule->arg.act.p[0];
list_for_each_entry(cache, &caches, list) {
if (!strcmp(cache->id, cache_ptr)) {
free(cache_ptr);
cache_ptr = cache;
break;
}
}
if (cache_ptr == hrqrule->arg.act.p[0]) {
Alert("Proxy '%s': unable to find the cache '%s' referenced by http-request cache-use rule.\n",
curproxy->id, (char *)hrqrule->arg.act.p[0]);
err++;
}
hrqrule->arg.act.p[0] = cache_ptr;
}
/* resolve the cache name to a ptr in the filter config */
list_for_each_entry(fconf, &curproxy->filter_configs, list) {
if (fconf->id != cache_store_flt_id)
continue;
cache_ptr = fconf->conf;
list_for_each_entry(cache, &caches, list) {
if (!strcmp(cache->id, cache_ptr)) {
/* there can be only one filter per cache, so we free it there */
free(cache_ptr);
cache_ptr = cache;
break;
}
}
if (cache_ptr == fconf->conf) {
Alert("Proxy '%s': unable to find the cache '%s' referenced by the filter 'cache'.\n",
curproxy->id, (char *)fconf->conf);
err++;
}
fconf->conf = cache_ptr;
}
}
return err;
}
struct flt_ops cache_ops = {
.init = cache_store_init,
/* Handle channels activity */
.channel_start_analyze = cache_store_chn_start_analyze,
/* Filter HTTP requests and responses */
.http_headers = cache_store_http_headers,
.http_end = cache_store_http_end,
.http_forward_data = cache_store_http_forward_data,
};
static struct action_kw_list http_res_actions = {
.kw = {
{ "cache-store", parse_cache_store },
{ NULL, NULL }
}
};
static struct action_kw_list http_req_actions = {
.kw = {
{ "cache-use", parse_cache_use },
{ NULL, NULL }
}
};
struct applet http_cache_applet = {
.obj_type = OBJ_TYPE_APPLET,
.name = "<CACHE>", /* used for logging */
.fct = http_cache_io_handler,
.release = NULL,
};
__attribute__((constructor))
static void __cache_init(void)
{
cfg_register_section("cache", cfg_parse_cache, cfg_post_parse_section_cache);
cfg_register_postparser("cache", cfg_cache_postparser);
http_res_keywords_register(&http_res_actions);
http_req_keywords_register(&http_req_actions);
pool2_cache_st = create_pool("cache_st", sizeof(struct cache_st), MEM_F_SHARED);
}