Mercurial > hg > nginx
view src/http/modules/ngx_http_range_filter_module.c @ 9300:5be23505292b
SSI: fixed incorrect or duplicate stub output.
Following 3518:eb3aaf8bd2a9 (0.8.37), r->request_output is only set
if there are data in the first buffer sent in the subrequest. As a
result, following the change mentioned this flag cannot be used to
prevent duplicate ngx_http_ssi_stub_output() calls, since it is not
set if there was already some output, but the first buffer was empty.
Still, when there are multiple subrequests, even an empty subrequest
response might be delayed by the postpone filter, leading to a second
call of ngx_http_ssi_stub_output() during finalization from
ngx_http_writer() the subreqest buffers are released by the postpone
filter. Since r->request_output is not set after the first call, this
resulted in duplicate stub output.
Additionally, checking only the first buffer might be wrong in some
unusual cases. For example, the first buffer might be empty if
$r->flush() is called before printing any data in the embedded Perl
module.
Depending on the postpone_output value and corresponding sizes, this
issue can result in either duplicate or unexpected stub output, or
"zero size buf in writer" alerts.
Following 8124:f5515e727656 (1.23.4), it became slightly easier to
reproduce the issue, as empty static files and empty cache items now
result in a response with an empty buffer. Before the change, an empty
proxied response can be used to reproduce the issue.
Fix is check all buffers and set r->request_output if any non-empty
buffers are sent. This ensures that all unusual cases of non-empty
responses are covered, and also that r->request_output will be set
after the first stub output, preventing duplicate output.
Reported by Jan Gassen.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Thu, 04 Jul 2024 17:41:28 +0300 |
parents | ae2d62bb12c0 |
children |
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> /* * the single part format: * * "HTTP/1.0 206 Partial Content" CRLF * ... header ... * "Content-Type: image/jpeg" CRLF * "Content-Length: SIZE" CRLF * "Content-Range: bytes START-END/SIZE" CRLF * CRLF * ... data ... * * * the multipart format: * * "HTTP/1.0 206 Partial Content" CRLF * ... header ... * "Content-Type: multipart/byteranges; boundary=0123456789" CRLF * CRLF * CRLF * "--0123456789" CRLF * "Content-Type: image/jpeg" CRLF * "Content-Range: bytes START0-END0/SIZE" CRLF * CRLF * ... data ... * CRLF * "--0123456789" CRLF * "Content-Type: image/jpeg" CRLF * "Content-Range: bytes START1-END1/SIZE" CRLF * CRLF * ... data ... * CRLF * "--0123456789--" CRLF */ typedef struct { off_t start; off_t end; ngx_str_t content_range; } ngx_http_range_t; typedef struct { off_t offset; ngx_str_t boundary_header; ngx_array_t ranges; } ngx_http_range_filter_ctx_t; static ngx_int_t ngx_http_range_parse(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_uint_t ranges); static ngx_int_t ngx_http_range_singlepart_header(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx); static ngx_int_t ngx_http_range_multipart_header(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx); static ngx_int_t ngx_http_range_not_satisfiable(ngx_http_request_t *r); static ngx_int_t ngx_http_range_test_overlapped(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in); static ngx_int_t ngx_http_range_singlepart_body(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in); static ngx_int_t ngx_http_range_multipart_body(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in); static ngx_int_t ngx_http_range_header_filter_init(ngx_conf_t *cf); static ngx_int_t ngx_http_range_body_filter_init(ngx_conf_t *cf); static ngx_http_module_t ngx_http_range_header_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_range_header_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_range_header_filter_module = { NGX_MODULE_V1, &ngx_http_range_header_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_module_t ngx_http_range_body_filter_module_ctx = { NULL, /* preconfiguration */ ngx_http_range_body_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_range_body_filter_module = { NGX_MODULE_V1, &ngx_http_range_body_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_range_header_filter(ngx_http_request_t *r) { time_t if_range_time; ngx_str_t *if_range, *etag; ngx_uint_t ranges; ngx_http_core_loc_conf_t *clcf; ngx_http_range_filter_ctx_t *ctx; if (r->http_version < NGX_HTTP_VERSION_10 || r->headers_out.status != NGX_HTTP_OK || (r != r->main && !r->subrequest_ranges) || r->headers_out.content_length_n == -1 || !r->allow_ranges) { return ngx_http_next_header_filter(r); } clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); if (clcf->max_ranges == 0) { return ngx_http_next_header_filter(r); } if (r->headers_in.range == NULL || r->headers_in.range->value.len < 7 || ngx_strncasecmp(r->headers_in.range->value.data, (u_char *) "bytes=", 6) != 0) { goto next_filter; } if (r->headers_in.if_range) { if_range = &r->headers_in.if_range->value; if (if_range->len >= 2 && if_range->data[if_range->len - 1] == '"') { if (r->headers_out.etag == NULL) { goto next_filter; } etag = &r->headers_out.etag->value; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http ir:%V etag:%V", if_range, etag); if (if_range->len != etag->len || ngx_strncmp(if_range->data, etag->data, etag->len) != 0) { goto next_filter; } goto parse; } if (r->headers_out.last_modified_time == (time_t) -1) { goto next_filter; } if_range_time = ngx_parse_http_time(if_range->data, if_range->len); ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http ir:%T lm:%T", if_range_time, r->headers_out.last_modified_time); if (if_range_time != r->headers_out.last_modified_time) { goto next_filter; } } parse: ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_range_filter_ctx_t)); if (ctx == NULL) { return NGX_ERROR; } ctx->offset = r->headers_out.content_offset; ranges = r->single_range ? 1 : clcf->max_ranges; switch (ngx_http_range_parse(r, ctx, ranges)) { case NGX_OK: ngx_http_set_ctx(r, ctx, ngx_http_range_body_filter_module); r->headers_out.status = NGX_HTTP_PARTIAL_CONTENT; r->headers_out.status_line.len = 0; if (ctx->ranges.nelts == 1) { return ngx_http_range_singlepart_header(r, ctx); } return ngx_http_range_multipart_header(r, ctx); case NGX_HTTP_RANGE_NOT_SATISFIABLE: return ngx_http_range_not_satisfiable(r); case NGX_ERROR: return NGX_ERROR; default: /* NGX_DECLINED */ break; } next_filter: r->headers_out.accept_ranges = ngx_list_push(&r->headers_out.headers); if (r->headers_out.accept_ranges == NULL) { return NGX_ERROR; } r->headers_out.accept_ranges->hash = 1; r->headers_out.accept_ranges->next = NULL; ngx_str_set(&r->headers_out.accept_ranges->key, "Accept-Ranges"); ngx_str_set(&r->headers_out.accept_ranges->value, "bytes"); return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_range_parse(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_uint_t ranges) { u_char *p; off_t start, end, size, content_length, cutoff, cutlim; ngx_uint_t suffix; ngx_http_range_t *range; ngx_http_range_filter_ctx_t *mctx; if (r != r->main) { mctx = ngx_http_get_module_ctx(r->main, ngx_http_range_body_filter_module); if (mctx) { ctx->ranges = mctx->ranges; return NGX_OK; } } if (ngx_array_init(&ctx->ranges, r->pool, 1, sizeof(ngx_http_range_t)) != NGX_OK) { return NGX_ERROR; } p = r->headers_in.range->value.data + 6; size = 0; content_length = r->headers_out.content_length_n; cutoff = NGX_MAX_OFF_T_VALUE / 10; cutlim = NGX_MAX_OFF_T_VALUE % 10; for ( ;; ) { start = 0; end = 0; suffix = 0; while (*p == ' ') { p++; } if (*p != '-') { if (*p < '0' || *p > '9') { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } while (*p >= '0' && *p <= '9') { if (start >= cutoff && (start > cutoff || *p - '0' > cutlim)) { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } start = start * 10 + (*p++ - '0'); } while (*p == ' ') { p++; } if (*p++ != '-') { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } while (*p == ' ') { p++; } if (*p == ',' || *p == '\0') { end = content_length; goto found; } } else { suffix = 1; p++; } if (*p < '0' || *p > '9') { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } while (*p >= '0' && *p <= '9') { if (end >= cutoff && (end > cutoff || *p - '0' > cutlim)) { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } end = end * 10 + (*p++ - '0'); } while (*p == ' ') { p++; } if (*p != ',' && *p != '\0') { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } if (suffix) { start = (end < content_length) ? content_length - end : 0; end = content_length - 1; } if (end >= content_length) { end = content_length; } else { end++; } found: if (start < end) { range = ngx_array_push(&ctx->ranges); if (range == NULL) { return NGX_ERROR; } range->start = start; range->end = end; if (size > NGX_MAX_OFF_T_VALUE - (end - start)) { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } size += end - start; if (ranges-- == 0) { return NGX_DECLINED; } } else if (start == 0) { return NGX_DECLINED; } if (*p++ != ',') { break; } } if (ctx->ranges.nelts == 0) { return NGX_HTTP_RANGE_NOT_SATISFIABLE; } if (size > content_length) { return NGX_DECLINED; } return NGX_OK; } static ngx_int_t ngx_http_range_singlepart_header(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx) { ngx_table_elt_t *content_range; ngx_http_range_t *range; if (r != r->main) { return ngx_http_next_header_filter(r); } content_range = ngx_list_push(&r->headers_out.headers); if (content_range == NULL) { return NGX_ERROR; } if (r->headers_out.content_range) { r->headers_out.content_range->hash = 0; } r->headers_out.content_range = content_range; content_range->hash = 1; content_range->next = NULL; ngx_str_set(&content_range->key, "Content-Range"); content_range->value.data = ngx_pnalloc(r->pool, sizeof("bytes -/") - 1 + 3 * NGX_OFF_T_LEN); if (content_range->value.data == NULL) { content_range->hash = 0; r->headers_out.content_range = NULL; return NGX_ERROR; } /* "Content-Range: bytes SSSS-EEEE/TTTT" header */ range = ctx->ranges.elts; content_range->value.len = ngx_sprintf(content_range->value.data, "bytes %O-%O/%O", range->start, range->end - 1, r->headers_out.content_length_n) - content_range->value.data; r->headers_out.content_length_n = range->end - range->start; r->headers_out.content_offset = range->start; if (r->headers_out.content_length) { r->headers_out.content_length->hash = 0; r->headers_out.content_length = NULL; } return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_range_multipart_header(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx) { off_t len; size_t size; ngx_uint_t i; ngx_http_range_t *range; ngx_atomic_uint_t boundary; size = sizeof(CRLF "--") - 1 + NGX_ATOMIC_T_LEN + sizeof(CRLF "Content-Type: ") - 1 + r->headers_out.content_type.len + sizeof(CRLF "Content-Range: bytes ") - 1; if (r->headers_out.content_type_len == r->headers_out.content_type.len && r->headers_out.charset.len) { size += sizeof("; charset=") - 1 + r->headers_out.charset.len; } ctx->boundary_header.data = ngx_pnalloc(r->pool, size); if (ctx->boundary_header.data == NULL) { return NGX_ERROR; } boundary = ngx_next_temp_number(0); /* * The boundary header of the range: * CRLF * "--0123456789" CRLF * "Content-Type: image/jpeg" CRLF * "Content-Range: bytes " */ if (r->headers_out.content_type_len == r->headers_out.content_type.len && r->headers_out.charset.len) { ctx->boundary_header.len = ngx_sprintf(ctx->boundary_header.data, CRLF "--%0muA" CRLF "Content-Type: %V; charset=%V" CRLF "Content-Range: bytes ", boundary, &r->headers_out.content_type, &r->headers_out.charset) - ctx->boundary_header.data; } else if (r->headers_out.content_type.len) { ctx->boundary_header.len = ngx_sprintf(ctx->boundary_header.data, CRLF "--%0muA" CRLF "Content-Type: %V" CRLF "Content-Range: bytes ", boundary, &r->headers_out.content_type) - ctx->boundary_header.data; } else { ctx->boundary_header.len = ngx_sprintf(ctx->boundary_header.data, CRLF "--%0muA" CRLF "Content-Range: bytes ", boundary) - ctx->boundary_header.data; } r->headers_out.content_type.data = ngx_pnalloc(r->pool, sizeof("Content-Type: multipart/byteranges; boundary=") - 1 + NGX_ATOMIC_T_LEN); if (r->headers_out.content_type.data == NULL) { return NGX_ERROR; } r->headers_out.content_type_lowcase = NULL; /* "Content-Type: multipart/byteranges; boundary=0123456789" */ r->headers_out.content_type.len = ngx_sprintf(r->headers_out.content_type.data, "multipart/byteranges; boundary=%0muA", boundary) - r->headers_out.content_type.data; r->headers_out.content_type_len = r->headers_out.content_type.len; r->headers_out.charset.len = 0; /* the size of the last boundary CRLF "--0123456789--" CRLF */ len = sizeof(CRLF "--") - 1 + NGX_ATOMIC_T_LEN + sizeof("--" CRLF) - 1; range = ctx->ranges.elts; for (i = 0; i < ctx->ranges.nelts; i++) { /* the size of the range: "SSSS-EEEE/TTTT" CRLF CRLF */ range[i].content_range.data = ngx_pnalloc(r->pool, 3 * NGX_OFF_T_LEN + 2 + 4); if (range[i].content_range.data == NULL) { return NGX_ERROR; } range[i].content_range.len = ngx_sprintf(range[i].content_range.data, "%O-%O/%O" CRLF CRLF, range[i].start, range[i].end - 1, r->headers_out.content_length_n) - range[i].content_range.data; len += ctx->boundary_header.len + range[i].content_range.len + (range[i].end - range[i].start); } r->headers_out.content_length_n = len; if (r->headers_out.content_length) { r->headers_out.content_length->hash = 0; r->headers_out.content_length = NULL; } if (r->headers_out.content_range) { r->headers_out.content_range->hash = 0; r->headers_out.content_range = NULL; } return ngx_http_next_header_filter(r); } static ngx_int_t ngx_http_range_not_satisfiable(ngx_http_request_t *r) { ngx_table_elt_t *content_range; r->headers_out.status = NGX_HTTP_RANGE_NOT_SATISFIABLE; content_range = ngx_list_push(&r->headers_out.headers); if (content_range == NULL) { return NGX_ERROR; } if (r->headers_out.content_range) { r->headers_out.content_range->hash = 0; } r->headers_out.content_range = content_range; content_range->hash = 1; content_range->next = NULL; ngx_str_set(&content_range->key, "Content-Range"); content_range->value.data = ngx_pnalloc(r->pool, sizeof("bytes */") - 1 + NGX_OFF_T_LEN); if (content_range->value.data == NULL) { content_range->hash = 0; r->headers_out.content_range = NULL; return NGX_ERROR; } content_range->value.len = ngx_sprintf(content_range->value.data, "bytes */%O", r->headers_out.content_length_n) - content_range->value.data; ngx_http_clear_content_length(r); return NGX_HTTP_RANGE_NOT_SATISFIABLE; } static ngx_int_t ngx_http_range_body_filter(ngx_http_request_t *r, ngx_chain_t *in) { ngx_http_range_filter_ctx_t *ctx; if (in == NULL) { return ngx_http_next_body_filter(r, in); } ctx = ngx_http_get_module_ctx(r, ngx_http_range_body_filter_module); if (ctx == NULL) { return ngx_http_next_body_filter(r, in); } if (ctx->ranges.nelts == 1) { return ngx_http_range_singlepart_body(r, ctx, in); } /* * multipart ranges are supported only if whole body is in a single buffer */ if (ngx_buf_special(in->buf)) { return ngx_http_next_body_filter(r, in); } if (ngx_http_range_test_overlapped(r, ctx, in) != NGX_OK) { return NGX_ERROR; } return ngx_http_range_multipart_body(r, ctx, in); } static ngx_int_t ngx_http_range_test_overlapped(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in) { off_t start, last; ngx_buf_t *buf; ngx_uint_t i; ngx_http_range_t *range; if (ctx->offset) { goto overlapped; } buf = in->buf; if (!buf->last_buf) { start = ctx->offset; last = ctx->offset + ngx_buf_size(buf); range = ctx->ranges.elts; for (i = 0; i < ctx->ranges.nelts; i++) { if (start > range[i].start || last < range[i].end) { goto overlapped; } } } ctx->offset = ngx_buf_size(buf); return NGX_OK; overlapped: ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0, "range in overlapped buffers"); return NGX_ERROR; } static ngx_int_t ngx_http_range_singlepart_body(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in) { off_t start, last; ngx_int_t rc; ngx_buf_t *buf; ngx_chain_t *out, *cl, *tl, **ll; ngx_http_range_t *range; out = NULL; ll = &out; range = ctx->ranges.elts; for (cl = in; cl; cl = cl->next) { buf = cl->buf; start = ctx->offset; last = ctx->offset + ngx_buf_size(buf); ctx->offset = last; ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http range body buf: %O-%O", start, last); if (ngx_buf_special(buf)) { if (range->end <= start) { continue; } tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = buf; tl->next = NULL; *ll = tl; ll = &tl->next; continue; } if (range->end <= start || range->start >= last) { ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, "http range body skip"); if (buf->in_file) { buf->file_pos = buf->file_last; } buf->pos = buf->last; buf->sync = 1; continue; } if (range->start > start) { if (buf->in_file) { buf->file_pos += range->start - start; } if (ngx_buf_in_memory(buf)) { buf->pos += (size_t) (range->start - start); } } if (range->end <= last) { if (buf->in_file) { buf->file_last -= last - range->end; } if (ngx_buf_in_memory(buf)) { buf->last -= (size_t) (last - range->end); } buf->last_buf = (r == r->main) ? 1 : 0; buf->last_in_chain = 1; tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = buf; tl->next = NULL; *ll = tl; ll = &tl->next; continue; } tl = ngx_alloc_chain_link(r->pool); if (tl == NULL) { return NGX_ERROR; } tl->buf = buf; tl->next = NULL; *ll = tl; ll = &tl->next; } rc = ngx_http_next_body_filter(r, out); while (out) { cl = out; out = out->next; ngx_free_chain(r->pool, cl); } return rc; } static ngx_int_t ngx_http_range_multipart_body(ngx_http_request_t *r, ngx_http_range_filter_ctx_t *ctx, ngx_chain_t *in) { ngx_buf_t *b, *buf; ngx_uint_t i; ngx_chain_t *out, *hcl, *rcl, *dcl, **ll; ngx_http_range_t *range; ll = &out; buf = in->buf; range = ctx->ranges.elts; for (i = 0; i < ctx->ranges.nelts; i++) { /* * The boundary header of the range: * CRLF * "--0123456789" CRLF * "Content-Type: image/jpeg" CRLF * "Content-Range: bytes " */ b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } b->memory = 1; b->pos = ctx->boundary_header.data; b->last = ctx->boundary_header.data + ctx->boundary_header.len; hcl = ngx_alloc_chain_link(r->pool); if (hcl == NULL) { return NGX_ERROR; } hcl->buf = b; /* "SSSS-EEEE/TTTT" CRLF CRLF */ b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } b->temporary = 1; b->pos = range[i].content_range.data; b->last = range[i].content_range.data + range[i].content_range.len; rcl = ngx_alloc_chain_link(r->pool); if (rcl == NULL) { return NGX_ERROR; } rcl->buf = b; /* the range data */ b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } b->in_file = buf->in_file; b->temporary = buf->temporary; b->memory = buf->memory; b->mmap = buf->mmap; b->file = buf->file; if (buf->in_file) { b->file_pos = buf->file_pos + range[i].start; b->file_last = buf->file_pos + range[i].end; } if (ngx_buf_in_memory(buf)) { b->pos = buf->pos + (size_t) range[i].start; b->last = buf->pos + (size_t) range[i].end; } dcl = ngx_alloc_chain_link(r->pool); if (dcl == NULL) { return NGX_ERROR; } dcl->buf = b; *ll = hcl; hcl->next = rcl; rcl->next = dcl; ll = &dcl->next; } /* the last boundary CRLF "--0123456789--" CRLF */ b = ngx_calloc_buf(r->pool); if (b == NULL) { return NGX_ERROR; } b->temporary = 1; b->last_buf = 1; b->pos = ngx_pnalloc(r->pool, sizeof(CRLF "--") - 1 + NGX_ATOMIC_T_LEN + sizeof("--" CRLF) - 1); if (b->pos == NULL) { return NGX_ERROR; } b->last = ngx_cpymem(b->pos, ctx->boundary_header.data, sizeof(CRLF "--") - 1 + NGX_ATOMIC_T_LEN); *b->last++ = '-'; *b->last++ = '-'; *b->last++ = CR; *b->last++ = LF; hcl = ngx_alloc_chain_link(r->pool); if (hcl == NULL) { return NGX_ERROR; } hcl->buf = b; hcl->next = NULL; *ll = hcl; return ngx_http_next_body_filter(r, out); } static ngx_int_t ngx_http_range_header_filter_init(ngx_conf_t *cf) { ngx_http_next_header_filter = ngx_http_top_header_filter; ngx_http_top_header_filter = ngx_http_range_header_filter; return NGX_OK; } static ngx_int_t ngx_http_range_body_filter_init(ngx_conf_t *cf) { ngx_http_next_body_filter = ngx_http_top_body_filter; ngx_http_top_body_filter = ngx_http_range_body_filter; return NGX_OK; }