Mercurial > hg > nginx
view src/http/modules/ngx_http_chunked_filter_module.c @ 7882:b4073527be81
Disabled control characters in URIs.
Control characters (0x00-0x1f, 0x7f) were never allowed in URIs, and must
be percent-encoded by clients. Further, these are not believed to appear
in practice. On the other hand, passing such characters might make various
attacks possible or easier, despite the fact that currently allowed control
characters are not significant for HTTP request parsing.
author | Maxim Dounin <mdounin@mdounin.ru> |
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date | Mon, 28 Jun 2021 18:01:15 +0300 |
parents | 1b068a4e82d8 |
children | 46e3542d51b3 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> typedef struct { ngx_chain_t *free; ngx_chain_t *busy; } ngx_http_chunked_filter_ctx_t; static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf); static ngx_chain_t *ngx_http_chunked_create_trailers(ngx_http_request_t *r, ngx_http_chunked_filter_ctx_t *ctx); static ngx_http_module_t ngx_http_chunked_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_chunked_filter_init, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL, /* merge server configuration */ NULL, /* create location configuration */ NULL /* merge location configuration */ }; ngx_module_t ngx_http_chunked_filter_module = { NGX_MODULE_V1, &ngx_http_chunked_filter_module_ctx, /* module context */ NULL, /* 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_http_output_header_filter_pt ngx_http_next_header_filter; static ngx_http_output_body_filter_pt ngx_http_next_body_filter; static ngx_int_t ngx_http_chunked_header_filter(ngx_http_request_t *r) { ngx_http_core_loc_conf_t *clcf; ngx_http_chunked_filter_ctx_t *ctx; if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED || r->headers_out.status == NGX_HTTP_NO_CONTENT || r->headers_out.status < NGX_HTTP_OK || r != r->main || r->method == NGX_HTTP_HEAD) { return ngx_http_next_header_filter(r); } if (r->headers_out.content_length_n == -1 || r->expect_trailers) { clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (r->http_version >= NGX_HTTP_VERSION_11 && clcf->chunked_transfer_encoding) { if (r->expect_trailers) { ngx_http_clear_content_length(r); } r->chunked = 1; ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_chunked_filter_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ngx_http_set_ctx(r, ctx, ngx_http_chunked_filter_module); } else if (r->headers_out.content_length_n == -1) { r->keepalive = 0; } } return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_chunked_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { u_char *chunk; off_t size; ngx_int_t rc; ngx_buf_t *b; ngx_chain_t *out, *cl, *tl, **ll; ngx_http_chunked_filter_ctx_t *ctx; if (in == NULL || !r->chunked || r->header_only) { return ngx_http_next_body_filter(r, in); } ctx = ngx_http_get_module_ctx(r, ngx_http_chunked_filter_module); out = NULL; ll = &out; size = 0; cl = in; for ( ;; ) { ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http chunk: %O", ngx_buf_size(cl->buf)); size += ngx_buf_size(cl->buf); if (cl->buf->flush || cl->buf->sync || ngx_buf_in_memory(cl->buf) || cl->buf->in_file) { tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = cl->buf; *ll = tl; ll = &tl->next; } if (cl->next == NULL) { break; } cl = cl->next; } if (size) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; chunk = b->start; if (chunk == NULL) { /* the "0000000000000000" is 64-bit hexadecimal string */ chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1); if (chunk == NULL) { return NGX_ERROR; } b->start = chunk; b->end = chunk + sizeof("0000000000000000" CRLF) - 1; } b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->memory = 0; b->temporary = 1; b->pos = chunk; b->last = ngx_sprintf(chunk, "%xO" CRLF, size); tl->next = out; out = tl; } if (cl->buf->last_buf) { tl = ngx_http_chunked_create_trailers(r, ctx); if (tl == NULL) { return NGX_ERROR; } cl->buf->last_buf = 0; *ll = tl; if (size == 0) { tl->buf->pos += 2; } } else if (size > 0) { tl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (tl == NULL) { return NGX_ERROR; } b = tl->buf; b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->temporary = 0; b->memory = 1; b->pos = (u_char *) CRLF; b->last = b->pos + 2; *ll = tl; } else { *ll = NULL; } rc = ngx_http_next_body_filter(r, out); ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out, (ngx_buf_tag_t) &ngx_http_chunked_filter_module); return rc; } static ngx_chain_t * ngx_http_chunked_create_trailers(ngx_http_request_t *r, ngx_http_chunked_filter_ctx_t *ctx) { size_t len; ngx_buf_t *b; ngx_uint_t i; ngx_chain_t *cl; ngx_list_part_t *part; ngx_table_elt_t *header; len = 0; part = &r->headers_out.trailers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } len += header[i].key.len + sizeof(": ") - 1 + header[i].value.len + sizeof(CRLF) - 1; } cl = ngx_chain_get_free_buf(r->pool, &ctx->free); if (cl == NULL) { return NULL; } b = cl->buf; b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module; b->temporary = 0; b->memory = 1; b->last_buf = 1; if (len == 0) { b->pos = (u_char *) CRLF "0" CRLF CRLF; b->last = b->pos + sizeof(CRLF "0" CRLF CRLF) - 1; return cl; } len += sizeof(CRLF "0" CRLF CRLF) - 1; b->pos = ngx_palloc(r->pool, len); if (b->pos == NULL) { return NULL; } b->last = b->pos; *b->last++ = CR; *b->last++ = LF; *b->last++ = '0'; *b->last++ = CR; *b->last++ = LF; part = &r->headers_out.trailers.part; header = part->elts; for (i = 0; /* void */; i++) { if (i >= part->nelts) { if (part->next == NULL) { break; } part = part->next; header = part->elts; i = 0; } if (header[i].hash == 0) { continue; } ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http trailer: \"%V: %V\"", &header[i].key, &header[i].value); b->last = ngx_copy(b->last, header[i].key.data, header[i].key.len); *b->last++ = ':'; *b->last++ = ' '; b->last = ngx_copy(b->last, header[i].value.data, header[i].value.len); *b->last++ = CR; *b->last++ = LF; } *b->last++ = CR; *b->last++ = LF; return cl; } static ngx_int_t ngx_http_chunked_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_chunked_header_filter; ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_chunked_body_filter; return NGX_OK; }