Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_memcached_module.c @ 6133:af7eba90645d
Win32: shared memory base addresses and remapping.
Two mechanisms are implemented to make it possible to store pointers
in shared memory on Windows, in particular on Windows Vista and later
versions with ASLR:
- The ngx_shm_remap() function added to allow remapping of a shared memory
zone to the address originally used for it in the master process. While
important, it doesn't solve the problem by itself as in many cases it's
not possible to use the address because of conflicts with other
allocations.
- We now create mappings at the same address in all processes by starting
mappings at predefined addresses normally unused by newborn processes.
These two mechanisms combined allow to use shared memory on Windows
almost without problems, including reloads.
Based on the patch by Sergey Brester:
http://mailman.nginx.org/pipermail/nginx-devel/2015-April/006836.html
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 27 Apr 2015 18:25:42 +0300 |
parents | 85f00678e54a |
children | f01ab2dbcfdc |
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_TAKE1, ngx_http_upstream_bind_set_slot, NGX_HTTP_LOC_CONF_OFFSET, offsetof(ngx_http_memcached_loc_conf_t, upstream.local), 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 (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:%z 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 (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.uri = { 0, NULL }; * conf->upstream.location = NULL; */ conf->upstream.local = NGX_CONF_UNSET_PTR; 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_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.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; }