Mercurial > hg > nginx
view src/http/modules/ngx_http_memcached_module.c @ 7678:bffcc5af1d72
Upstream: drop extra data sent by upstream.
Previous behaviour was to pass everything to the client, but this
seems to be suboptimal and causes issues (ticket #1695). Fix is to
drop extra data instead, as it naturally happens in most clients.
This change covers generic buffered and unbuffered filters as used
in the scgi and uwsgi modules. Appropriate input filter init
handlers are provided by the scgi and uwsgi modules to set corresponding
lengths.
Note that for responses to HEAD requests there is an exception:
we do allow any response length. This is because responses to HEAD
requests might be actual full responses, and it is up to nginx
to remove the response body. If caching is enabled, only full
responses matching the Content-Length header will be cached
(see b779728b180c).
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 06 Jul 2020 18:36:22 +0300 |
parents | 7731c710796f |
children | d26db4f82d7d |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_http_upstream_conf_t upstream; ngx_int_t index; ngx_uint_t gzip_flag; } ngx_http_memcached_loc_conf_t; typedef struct { size_t rest; ngx_http_request_t *request; ngx_str_t key; } ngx_http_memcached_ctx_t; static ngx_int_t ngx_http_memcached_create_request(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_reinit_request(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_process_header(ngx_http_request_t *r); static ngx_int_t ngx_http_memcached_filter_init(void *data); static ngx_int_t ngx_http_memcached_filter(void *data, ssize_t bytes); static void ngx_http_memcached_abort_request(ngx_http_request_t *r); static void ngx_http_memcached_finalize_request(ngx_http_request_t *r, ngx_int_t rc); static void *ngx_http_memcached_create_loc_conf(ngx_conf_t *cf); static char *ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child); static char *ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_conf_bitmask_t ngx_http_memcached_next_upstream_masks[] = { { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR }, { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT }, { ngx_string("invalid_response"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER }, { ngx_string("not_found"), NGX_HTTP_UPSTREAM_FT_HTTP_404 }, { ngx_string("off"), NGX_HTTP_UPSTREAM_FT_OFF }, { ngx_null_string, 0 } }; static ngx_command_t ngx_http_memcached_commands[] = { { ngx_string("memcached_pass"), NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF|NGX_CONF_TAKE1, ngx_http_memcached_pass, NGX_HTTP_LOC_CONF_OFFSET, 0, NULL }, { ngx_string("memcached_bind"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12, ngx_http_upstream_bind_set_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.local), NULL }, { ngx_string("memcached_socket_keepalive"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG, ngx_conf_set_flag_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.socket_keepalive), NULL }, { ngx_string("memcached_connect_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.connect_timeout), NULL }, { ngx_string("memcached_send_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.send_timeout), NULL }, { ngx_string("memcached_buffer_size"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_size_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.buffer_size), NULL }, { ngx_string("memcached_read_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.read_timeout), NULL }, { ngx_string("memcached_next_upstream"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, ngx_conf_set_bitmask_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream), &ngx_http_memcached_next_upstream_masks }, { ngx_string("memcached_next_upstream_tries"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream_tries), NULL }, { ngx_string("memcached_next_upstream_timeout"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_msec_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.next_upstream_timeout), NULL }, { ngx_string("memcached_gzip_flag"), NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1, ngx_conf_set_num_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, gzip_flag), NULL }, ngx_null_command }; static ngx_http_module_t ngx_http_memcached_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ ngx_http_memcached_create_loc_conf, /* create location configuration */ ngx_http_memcached_merge_loc_conf /* merge location configuration */ }; ngx_module_t ngx_http_memcached_module = { NGX_MODULE_V1, &ngx_http_memcached_module_ctx, /* module context */ ngx_http_memcached_commands, /* module directives */ NGX_HTTP_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static ngx_str_t ngx_http_memcached_key = ngx_string("memcached_key"); #define NGX_HTTP_MEMCACHED_END (sizeof(ngx_http_memcached_end) - 1) static u_char ngx_http_memcached_end[] = CRLF "END" CRLF; static ngx_int_t ngx_http_memcached_handler(ngx_http_request_t *r) { ngx_int_t rc; ngx_http_upstream_t *u; ngx_http_memcached_ctx_t *ctx; ngx_http_memcached_loc_conf_t *mlcf; if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) { return NGX_HTTP_NOT_ALLOWED; } rc = ngx_http_discard_request_body(r); if (rc != NGX_OK) { return rc; } if (ngx_http_set_content_type(r) != NGX_OK) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } if (ngx_http_upstream_create(r) != NGX_OK) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } u = r->upstream; ngx_str_set(&u->schema, "memcached://"); u->output.tag = (ngx_buf_tag_t) &ngx_http_memcached_module; mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); u->conf = &mlcf->upstream; u->create_request = ngx_http_memcached_create_request; u->reinit_request = ngx_http_memcached_reinit_request; u->process_header = ngx_http_memcached_process_header; u->abort_request = ngx_http_memcached_abort_request; u->finalize_request = ngx_http_memcached_finalize_request; ctx = ngx_palloc(r->pool, sizeof(ngx_http_memcached_ctx_t)); if (ctx == NULL) { return NGX_HTTP_INTERNAL_SERVER_ERROR; } ctx->request = r; ngx_http_set_ctx(r, ctx, ngx_http_memcached_module); u->input_filter_init = ngx_http_memcached_filter_init; u->input_filter = ngx_http_memcached_filter; u->input_filter_ctx = ctx; r->main->count++; ngx_http_upstream_init(r); return NGX_DONE; } static ngx_int_t ngx_http_memcached_create_request(ngx_http_request_t *r) { size_t len; uintptr_t escape; ngx_buf_t *b; ngx_chain_t *cl; ngx_http_memcached_ctx_t *ctx; ngx_http_variable_value_t *vv; ngx_http_memcached_loc_conf_t *mlcf; mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); vv = ngx_http_get_indexed_variable(r, mlcf->index); if (vv == NULL || vv->not_found || vv->len == 0) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "the \"$memcached_key\" variable is not set"); return NGX_ERROR; } escape = 2 * ngx_escape_uri(NULL, vv->data, vv->len, NGX_ESCAPE_MEMCACHED); len = sizeof("get ") - 1 + vv->len + escape + sizeof(CRLF) - 1; b = ngx_create_temp_buf(r->pool, len); if (b == NULL) { return NGX_ERROR; } cl = ngx_alloc_chain_link(r->pool); if (cl == NULL) { return NGX_ERROR; } cl->buf = b; cl->next = NULL; r->upstream->request_bufs = cl; *b->last++ = 'g'; *b->last++ = 'e'; *b->last++ = 't'; *b->last++ = ' '; ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module); ctx->key.data = b->last; if (escape == 0) { b->last = ngx_copy(b->last, vv->data, vv->len); } else { b->last = (u_char *) ngx_escape_uri(b->last, vv->data, vv->len, NGX_ESCAPE_MEMCACHED); } ctx->key.len = b->last - ctx->key.data; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http memcached request: \"%V\"", &ctx->key); *b->last++ = CR; *b->last++ = LF; return NGX_OK; } static ngx_int_t ngx_http_memcached_reinit_request(ngx_http_request_t *r) { return NGX_OK; } static ngx_int_t ngx_http_memcached_process_header(ngx_http_request_t *r) { u_char *p, *start; ngx_str_t line; ngx_uint_t flags; ngx_table_elt_t *h; ngx_http_upstream_t *u; ngx_http_memcached_ctx_t *ctx; ngx_http_memcached_loc_conf_t *mlcf; u = r->upstream; for (p = u->buffer.pos; p < u->buffer.last; p++) { if (*p == LF) { goto found; } } return NGX_AGAIN; found: line.data = u->buffer.pos; line.len = p - u->buffer.pos; if (line.len == 0 || *(p - 1) != CR) { goto no_valid; } *p = '\0'; line.len--; ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "memcached: \"%V\"", &line); p = u->buffer.pos; ctx = ngx_http_get_module_ctx(r, ngx_http_memcached_module); mlcf = ngx_http_get_module_loc_conf(r, ngx_http_memcached_module); if (ngx_strncmp(p, "VALUE ", sizeof("VALUE ") - 1) == 0) { p += sizeof("VALUE ") - 1; if (ngx_strncmp(p, ctx->key.data, ctx->key.len) != 0) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid key in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } p += ctx->key.len; if (*p++ != ' ') { goto no_valid; } /* flags */ start = p; while (*p) { if (*p++ == ' ') { if (mlcf->gzip_flag) { goto flags; } else { goto length; } } } goto no_valid; flags: flags = ngx_atoi(start, p - start - 1); if (flags == (ngx_uint_t) NGX_ERROR) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid flags in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } if (flags & mlcf->gzip_flag) { h = ngx_list_push(&r->headers_out.headers); if (h == NULL) { return NGX_ERROR; } h->hash = 1; ngx_str_set(&h->key, "Content-Encoding"); ngx_str_set(&h->value, "gzip"); r->headers_out.content_encoding = h; } length: start = p; p = line.data + line.len; u->headers_in.content_length_n = ngx_atoof(start, p - start); if (u->headers_in.content_length_n == NGX_ERROR) { ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid length in response \"%V\" " "for key \"%V\"", &line, &ctx->key); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } u->headers_in.status_n = 200; u->state->status = 200; u->buffer.pos = p + sizeof(CRLF) - 1; return NGX_OK; } if (ngx_strcmp(p, "END\x0d") == 0) { ngx_log_error(NGX_LOG_INFO, r->connection->log, 0, "key: \"%V\" was not found by memcached", &ctx->key); u->headers_in.content_length_n = 0; u->headers_in.status_n = 404; u->state->status = 404; u->buffer.pos = p + sizeof("END" CRLF) - 1; u->keepalive = 1; return NGX_OK; } no_valid: ngx_log_error(NGX_LOG_ERR, r->connection->log, 0, "memcached sent invalid response: \"%V\"", &line); return NGX_HTTP_UPSTREAM_INVALID_HEADER; } static ngx_int_t ngx_http_memcached_filter_init(void *data) { ngx_http_memcached_ctx_t *ctx = data; ngx_http_upstream_t *u; u = ctx->request->upstream; if (u->headers_in.status_n != 404) { u->length = u->headers_in.content_length_n + NGX_HTTP_MEMCACHED_END; ctx->rest = NGX_HTTP_MEMCACHED_END; } else { u->length = 0; } return NGX_OK; } static ngx_int_t ngx_http_memcached_filter(void *data, ssize_t bytes) { ngx_http_memcached_ctx_t *ctx = data; u_char *last; ngx_buf_t *b; ngx_chain_t *cl, **ll; ngx_http_upstream_t *u; u = ctx->request->upstream; b = &u->buffer; if (u->length == (ssize_t) ctx->rest) { if (bytes > u->length || ngx_strncmp(b->last, ngx_http_memcached_end + NGX_HTTP_MEMCACHED_END - ctx->rest, bytes) != 0) { ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0, "memcached sent invalid trailer"); u->length = 0; ctx->rest = 0; return NGX_OK; } u->length -= bytes; ctx->rest -= bytes; if (u->length == 0) { u->keepalive = 1; } return NGX_OK; } for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) { ll = &cl->next; } cl = ngx_chain_get_free_buf(ctx->request->pool, &u->free_bufs); if (cl == NULL) { return NGX_ERROR; } cl->buf->flush = 1; cl->buf->memory = 1; *ll = cl; last = b->last; cl->buf->pos = last; b->last += bytes; cl->buf->last = b->last; cl->buf->tag = u->output.tag; ngx_log_debug4(NGX_LOG_DEBUG_HTTP, ctx->request->connection->log, 0, "memcached filter bytes:%z size:%z length:%O rest:%z", bytes, b->last - b->pos, u->length, ctx->rest); if (bytes <= (ssize_t) (u->length - NGX_HTTP_MEMCACHED_END)) { u->length -= bytes; return NGX_OK; } last += (size_t) (u->length - NGX_HTTP_MEMCACHED_END); if (bytes > u->length || ngx_strncmp(last, ngx_http_memcached_end, b->last - last) != 0) { ngx_log_error(NGX_LOG_ERR, ctx->request->connection->log, 0, "memcached sent invalid trailer"); b->last = last; cl->buf->last = last; u->length = 0; ctx->rest = 0; return NGX_OK; } ctx->rest -= b->last - last; b->last = last; cl->buf->last = last; u->length = ctx->rest; if (u->length == 0) { u->keepalive = 1; } return NGX_OK; } static void ngx_http_memcached_abort_request(ngx_http_request_t *r) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "abort http memcached request"); return; } static void ngx_http_memcached_finalize_request(ngx_http_request_t *r, ngx_int_t rc) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "finalize http memcached request"); return; } static void * ngx_http_memcached_create_loc_conf(ngx_conf_t *cf) { ngx_http_memcached_loc_conf_t *conf; conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_memcached_loc_conf_t)); if (conf == NULL) { return NULL; } /* * set by ngx_pcalloc(): * * conf->upstream.bufs.num = 0; * conf->upstream.next_upstream = 0; * conf->upstream.temp_path = NULL; */ conf->upstream.local = NGX_CONF_UNSET_PTR; conf->upstream.socket_keepalive = NGX_CONF_UNSET; conf->upstream.next_upstream_tries = NGX_CONF_UNSET_UINT; conf->upstream.connect_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.send_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.read_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.next_upstream_timeout = NGX_CONF_UNSET_MSEC; conf->upstream.buffer_size = NGX_CONF_UNSET_SIZE; /* the hardcoded values */ conf->upstream.cyclic_temp_file = 0; conf->upstream.buffering = 0; conf->upstream.ignore_client_abort = 0; conf->upstream.send_lowat = 0; conf->upstream.bufs.num = 0; conf->upstream.busy_buffers_size = 0; conf->upstream.max_temp_file_size = 0; conf->upstream.temp_file_write_size = 0; conf->upstream.intercept_errors = 1; conf->upstream.intercept_404 = 1; conf->upstream.pass_request_headers = 0; conf->upstream.pass_request_body = 0; conf->upstream.force_ranges = 1; conf->index = NGX_CONF_UNSET; conf->gzip_flag = NGX_CONF_UNSET_UINT; return conf; } static char * ngx_http_memcached_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_http_memcached_loc_conf_t *prev = parent; ngx_http_memcached_loc_conf_t *conf = child; ngx_conf_merge_ptr_value(conf->upstream.local, prev->upstream.local, NULL); ngx_conf_merge_value(conf->upstream.socket_keepalive, prev->upstream.socket_keepalive, 0); ngx_conf_merge_uint_value(conf->upstream.next_upstream_tries, prev->upstream.next_upstream_tries, 0); ngx_conf_merge_msec_value(conf->upstream.connect_timeout, prev->upstream.connect_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.send_timeout, prev->upstream.send_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.read_timeout, prev->upstream.read_timeout, 60000); ngx_conf_merge_msec_value(conf->upstream.next_upstream_timeout, prev->upstream.next_upstream_timeout, 0); ngx_conf_merge_size_value(conf->upstream.buffer_size, prev->upstream.buffer_size, (size_t) ngx_pagesize); ngx_conf_merge_bitmask_value(conf->upstream.next_upstream, prev->upstream.next_upstream, (NGX_CONF_BITMASK_SET |NGX_HTTP_UPSTREAM_FT_ERROR |NGX_HTTP_UPSTREAM_FT_TIMEOUT)); if (conf->upstream.next_upstream & NGX_HTTP_UPSTREAM_FT_OFF) { conf->upstream.next_upstream = NGX_CONF_BITMASK_SET |NGX_HTTP_UPSTREAM_FT_OFF; } if (conf->upstream.upstream == NULL) { conf->upstream.upstream = prev->upstream.upstream; } if (conf->index == NGX_CONF_UNSET) { conf->index = prev->index; } ngx_conf_merge_uint_value(conf->gzip_flag, prev->gzip_flag, 0); return NGX_CONF_OK; } static char * ngx_http_memcached_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_memcached_loc_conf_t *mlcf = conf; ngx_str_t *value; ngx_url_t u; ngx_http_core_loc_conf_t *clcf; if (mlcf->upstream.upstream) { return "is duplicate"; } value = cf->args->elts; ngx_memzero(&u, sizeof(ngx_url_t)); u.url = value[1]; u.no_resolve = 1; mlcf->upstream.upstream = ngx_http_upstream_add(cf, &u, 0); if (mlcf->upstream.upstream == NULL) { return NGX_CONF_ERROR; } clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module); clcf->handler = ngx_http_memcached_handler; if (clcf->name.len && clcf->name.data[clcf->name.len - 1] == '/') { clcf->auto_redirect = 1; } mlcf->index = ngx_http_get_variable_index(cf, &ngx_http_memcached_key); if (mlcf->index == NGX_ERROR) { return NGX_CONF_ERROR; } return NGX_CONF_OK; }