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-rw-r--r--modules/http/http_filters.c1941
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diff --git a/modules/http/http_filters.c b/modules/http/http_filters.c
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--- /dev/null
+++ b/modules/http/http_filters.c
@@ -0,0 +1,1941 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * http_filter.c --- HTTP routines which either filters or deal with filters.
+ */
+
+#include "apr.h"
+#include "apr_strings.h"
+#include "apr_buckets.h"
+#include "apr_lib.h"
+#include "apr_signal.h"
+
+#define APR_WANT_STDIO /* for sscanf */
+#define APR_WANT_STRFUNC
+#define APR_WANT_MEMFUNC
+#include "apr_want.h"
+
+#include "util_filter.h"
+#include "ap_config.h"
+#include "httpd.h"
+#include "http_config.h"
+#include "http_core.h"
+#include "http_protocol.h"
+#include "http_main.h"
+#include "http_request.h"
+#include "http_vhost.h"
+#include "http_connection.h"
+#include "http_log.h" /* For errors detected in basic auth common
+ * support code... */
+#include "apr_date.h" /* For apr_date_parse_http and APR_DATE_BAD */
+#include "util_charset.h"
+#include "util_ebcdic.h"
+#include "util_time.h"
+
+#include "mod_core.h"
+
+#if APR_HAVE_STDARG_H
+#include <stdarg.h>
+#endif
+#if APR_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+APLOG_USE_MODULE(http);
+
+typedef struct http_filter_ctx
+{
+ apr_off_t remaining;
+ apr_off_t limit;
+ apr_off_t limit_used;
+ apr_int32_t chunk_used;
+ apr_int32_t chunk_bws;
+ apr_int32_t chunkbits;
+ enum
+ {
+ BODY_NONE, /* streamed data */
+ BODY_LENGTH, /* data constrained by content length */
+ BODY_CHUNK, /* chunk expected */
+ BODY_CHUNK_PART, /* chunk digits */
+ BODY_CHUNK_EXT, /* chunk extension */
+ BODY_CHUNK_CR, /* got space(s) after digits, expect [CR]LF or ext */
+ BODY_CHUNK_LF, /* got CR after digits or ext, expect LF */
+ BODY_CHUNK_DATA, /* data constrained by chunked encoding */
+ BODY_CHUNK_END, /* chunked data terminating CRLF */
+ BODY_CHUNK_END_LF, /* got CR after data, expect LF */
+ BODY_CHUNK_TRAILER /* trailers */
+ } state;
+ unsigned int eos_sent :1,
+ seen_data:1;
+ apr_bucket_brigade *bb;
+} http_ctx_t;
+
+/* bail out if some error in the HTTP input filter happens */
+static apr_status_t bail_out_on_error(http_ctx_t *ctx,
+ ap_filter_t *f,
+ int http_error)
+{
+ apr_bucket *e;
+ apr_bucket_brigade *bb = ctx->bb;
+
+ apr_brigade_cleanup(bb);
+
+ if (f->r->proxyreq == PROXYREQ_RESPONSE) {
+ switch (http_error) {
+ case HTTP_REQUEST_ENTITY_TOO_LARGE:
+ return APR_ENOSPC;
+
+ case HTTP_REQUEST_TIME_OUT:
+ return APR_INCOMPLETE;
+
+ case HTTP_NOT_IMPLEMENTED:
+ return APR_ENOTIMPL;
+
+ default:
+ return APR_EGENERAL;
+ }
+ }
+
+ e = ap_bucket_error_create(http_error,
+ NULL, f->r->pool,
+ f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, e);
+ ctx->eos_sent = 1;
+ /* If chunked encoding / content-length are corrupt, we may treat parts
+ * of this request's body as the next one's headers.
+ * To be safe, disable keep-alive.
+ */
+ f->r->connection->keepalive = AP_CONN_CLOSE;
+ return ap_pass_brigade(f->r->output_filters, bb);
+}
+
+/**
+ * Parse a chunk line with optional extension, detect overflow.
+ * There are several error cases:
+ * 1) If the chunk link is misformatted, APR_EINVAL is returned.
+ * 2) If the conversion would require too many bits, APR_EGENERAL is returned.
+ * 3) If the conversion used the correct number of bits, but an overflow
+ * caused only the sign bit to flip, then APR_ENOSPC is returned.
+ * A negative chunk length always indicates an overflow error.
+ */
+static apr_status_t parse_chunk_size(http_ctx_t *ctx, const char *buffer,
+ apr_size_t len, int linelimit, int strict)
+{
+ apr_size_t i = 0;
+
+ while (i < len) {
+ char c = buffer[i];
+
+ ap_xlate_proto_from_ascii(&c, 1);
+
+ /* handle CRLF after the chunk */
+ if (ctx->state == BODY_CHUNK_END
+ || ctx->state == BODY_CHUNK_END_LF) {
+ if (c == LF) {
+ if (strict && (ctx->state != BODY_CHUNK_END_LF)) {
+ /*
+ * CR missing before LF.
+ */
+ return APR_EINVAL;
+ }
+ ctx->state = BODY_CHUNK;
+ }
+ else if (c == CR && ctx->state == BODY_CHUNK_END) {
+ ctx->state = BODY_CHUNK_END_LF;
+ }
+ else {
+ /*
+ * CRLF expected.
+ */
+ return APR_EINVAL;
+ }
+ i++;
+ continue;
+ }
+
+ /* handle start of the chunk */
+ if (ctx->state == BODY_CHUNK) {
+ if (!apr_isxdigit(c)) {
+ /*
+ * Detect invalid character at beginning. This also works for
+ * empty chunk size lines.
+ */
+ return APR_EINVAL;
+ }
+ else {
+ ctx->state = BODY_CHUNK_PART;
+ }
+ ctx->remaining = 0;
+ ctx->chunkbits = sizeof(apr_off_t) * 8;
+ ctx->chunk_used = 0;
+ ctx->chunk_bws = 0;
+ }
+
+ if (c == LF) {
+ if (strict && (ctx->state != BODY_CHUNK_LF)) {
+ /*
+ * CR missing before LF.
+ */
+ return APR_EINVAL;
+ }
+ if (ctx->remaining) {
+ ctx->state = BODY_CHUNK_DATA;
+ }
+ else {
+ ctx->state = BODY_CHUNK_TRAILER;
+ }
+ }
+ else if (ctx->state == BODY_CHUNK_LF) {
+ /*
+ * LF expected.
+ */
+ return APR_EINVAL;
+ }
+ else if (c == CR) {
+ ctx->state = BODY_CHUNK_LF;
+ }
+ else if (c == ';') {
+ ctx->state = BODY_CHUNK_EXT;
+ }
+ else if (ctx->state == BODY_CHUNK_EXT) {
+ /*
+ * Control chars (excluding tabs) are invalid.
+ * TODO: more precisely limit input
+ */
+ if (c != '\t' && apr_iscntrl(c)) {
+ return APR_EINVAL;
+ }
+ }
+ else if (c == ' ' || c == '\t') {
+ /* Be lenient up to 10 implied *LWS, a legacy of RFC 2616,
+ * and noted as errata to RFC7230;
+ * https://www.rfc-editor.org/errata_search.php?rfc=7230&eid=4667
+ */
+ ctx->state = BODY_CHUNK_CR;
+ if (++ctx->chunk_bws > 10) {
+ return APR_EINVAL;
+ }
+ }
+ else if (ctx->state == BODY_CHUNK_CR) {
+ /*
+ * ';', CR or LF expected.
+ */
+ return APR_EINVAL;
+ }
+ else if (ctx->state == BODY_CHUNK_PART) {
+ int xvalue;
+
+ /* ignore leading zeros */
+ if (!ctx->remaining && c == '0') {
+ i++;
+ continue;
+ }
+
+ ctx->chunkbits -= 4;
+ if (ctx->chunkbits < 0) {
+ /* overflow */
+ return APR_ENOSPC;
+ }
+
+ if (c >= '0' && c <= '9') {
+ xvalue = c - '0';
+ }
+ else if (c >= 'A' && c <= 'F') {
+ xvalue = c - 'A' + 0xa;
+ }
+ else if (c >= 'a' && c <= 'f') {
+ xvalue = c - 'a' + 0xa;
+ }
+ else {
+ /* bogus character */
+ return APR_EINVAL;
+ }
+
+ ctx->remaining = (ctx->remaining << 4) | xvalue;
+ if (ctx->remaining < 0) {
+ /* overflow */
+ return APR_ENOSPC;
+ }
+ }
+ else {
+ /* Should not happen */
+ return APR_EGENERAL;
+ }
+
+ i++;
+ }
+
+ /* sanity check */
+ ctx->chunk_used += len;
+ if (ctx->chunk_used < 0 || ctx->chunk_used > linelimit) {
+ return APR_ENOSPC;
+ }
+
+ return APR_SUCCESS;
+}
+
+static apr_status_t read_chunked_trailers(http_ctx_t *ctx, ap_filter_t *f,
+ apr_bucket_brigade *b, int merge)
+{
+ int rv;
+ apr_bucket *e;
+ request_rec *r = f->r;
+ apr_table_t *saved_headers_in = r->headers_in;
+ int saved_status = r->status;
+
+ r->status = HTTP_OK;
+ r->headers_in = r->trailers_in;
+ apr_table_clear(r->headers_in);
+ ap_get_mime_headers(r);
+
+ if(r->status == HTTP_OK) {
+ r->status = saved_status;
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ rv = APR_SUCCESS;
+ }
+ else {
+ const char *error_notes = apr_table_get(r->notes,
+ "error-notes");
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(02656)
+ "Error while reading HTTP trailer: %i%s%s",
+ r->status, error_notes ? ": " : "",
+ error_notes ? error_notes : "");
+ rv = APR_EINVAL;
+ }
+
+ if(!merge) {
+ r->headers_in = saved_headers_in;
+ }
+ else {
+ r->headers_in = apr_table_overlay(r->pool, saved_headers_in,
+ r->trailers_in);
+ }
+
+ return rv;
+}
+
+/* This is the HTTP_INPUT filter for HTTP requests and responses from
+ * proxied servers (mod_proxy). It handles chunked and content-length
+ * bodies. This can only be inserted/used after the headers
+ * are successfully parsed.
+ */
+apr_status_t ap_http_filter(ap_filter_t *f, apr_bucket_brigade *b,
+ ap_input_mode_t mode, apr_read_type_e block,
+ apr_off_t readbytes)
+{
+ core_server_config *conf =
+ (core_server_config *) ap_get_module_config(f->r->server->module_config,
+ &core_module);
+ int strict = (conf->http_conformance != AP_HTTP_CONFORMANCE_UNSAFE);
+ apr_bucket *e;
+ http_ctx_t *ctx = f->ctx;
+ apr_status_t rv;
+ int http_error = HTTP_REQUEST_ENTITY_TOO_LARGE;
+ int again;
+
+ /* just get out of the way of things we don't want. */
+ if (mode != AP_MODE_READBYTES && mode != AP_MODE_GETLINE) {
+ return ap_get_brigade(f->next, b, mode, block, readbytes);
+ }
+
+ if (!ctx) {
+ const char *tenc, *lenp;
+ f->ctx = ctx = apr_pcalloc(f->r->pool, sizeof(*ctx));
+ ctx->state = BODY_NONE;
+ ctx->bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+
+ /* LimitRequestBody does not apply to proxied responses.
+ * Consider implementing this check in its own filter.
+ * Would adding a directive to limit the size of proxied
+ * responses be useful?
+ */
+ if (!f->r->proxyreq) {
+ ctx->limit = ap_get_limit_req_body(f->r);
+ }
+ else {
+ ctx->limit = 0;
+ }
+
+ tenc = apr_table_get(f->r->headers_in, "Transfer-Encoding");
+ lenp = apr_table_get(f->r->headers_in, "Content-Length");
+
+ if (tenc) {
+ if (ap_is_chunked(f->r->pool, tenc)) {
+ ctx->state = BODY_CHUNK;
+ }
+ else if (f->r->proxyreq == PROXYREQ_RESPONSE) {
+ /* http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-23
+ * Section 3.3.3.3: "If a Transfer-Encoding header field is
+ * present in a response and the chunked transfer coding is not
+ * the final encoding, the message body length is determined by
+ * reading the connection until it is closed by the server."
+ */
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r, APLOGNO(02555)
+ "Unknown Transfer-Encoding: %s; "
+ "using read-until-close", tenc);
+ tenc = NULL;
+ }
+ else {
+ /* Something that isn't a HTTP request, unless some future
+ * edition defines new transfer encodings, is unsupported.
+ */
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r, APLOGNO(01585)
+ "Unknown Transfer-Encoding: %s", tenc);
+ return bail_out_on_error(ctx, f, HTTP_BAD_REQUEST);
+ }
+ lenp = NULL;
+ }
+ if (lenp) {
+ ctx->state = BODY_LENGTH;
+
+ /* Protects against over/underflow, non-digit chars in the
+ * string, leading plus/minus signs, trailing characters and
+ * a negative number.
+ */
+ if (!ap_parse_strict_length(&ctx->remaining, lenp)) {
+ ctx->remaining = 0;
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r, APLOGNO(01587)
+ "Invalid Content-Length");
+
+ return bail_out_on_error(ctx, f, HTTP_BAD_REQUEST);
+ }
+
+ /* If we have a limit in effect and we know the C-L ahead of
+ * time, stop it here if it is invalid.
+ */
+ if (ctx->limit && ctx->limit < ctx->remaining) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r, APLOGNO(01588)
+ "Requested content-length of %" APR_OFF_T_FMT
+ " is larger than the configured limit"
+ " of %" APR_OFF_T_FMT, ctx->remaining, ctx->limit);
+ return bail_out_on_error(ctx, f, HTTP_REQUEST_ENTITY_TOO_LARGE);
+ }
+ }
+
+ /* If we don't have a request entity indicated by the headers, EOS.
+ * (BODY_NONE is a valid intermediate state due to trailers,
+ * but it isn't a valid starting state.)
+ *
+ * RFC 2616 Section 4.4 note 5 states that connection-close
+ * is invalid for a request entity - request bodies must be
+ * denoted by C-L or T-E: chunked.
+ *
+ * Note that since the proxy uses this filter to handle the
+ * proxied *response*, proxy responses MUST be exempt.
+ */
+ if (ctx->state == BODY_NONE && f->r->proxyreq != PROXYREQ_RESPONSE) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ return APR_SUCCESS;
+ }
+ }
+
+ /* Since we're about to read data, send 100-Continue if needed.
+ * Only valid on chunked and C-L bodies where the C-L is > 0.
+ *
+ * If the read is to be nonblocking though, the caller may not want to
+ * handle this just now (e.g. mod_proxy_http), and is prepared to read
+ * nothing if the client really waits for 100 continue, so we don't
+ * send it now and wait for later blocking read.
+ *
+ * In any case, even if r->expecting remains set at the end of the
+ * request handling, ap_set_keepalive() will finally do the right
+ * thing (i.e. "Connection: close" the connection).
+ */
+ if (block == APR_BLOCK_READ
+ && (ctx->state == BODY_CHUNK
+ || (ctx->state == BODY_LENGTH && ctx->remaining > 0))
+ && f->r->expecting_100 && f->r->proto_num >= HTTP_VERSION(1,1)
+ && !(ctx->eos_sent || f->r->eos_sent || f->r->bytes_sent)) {
+ if (!ap_is_HTTP_SUCCESS(f->r->status)) {
+ ctx->state = BODY_NONE;
+ ctx->eos_sent = 1; /* send EOS below */
+ }
+ else if (!ctx->seen_data) {
+ int saved_status = f->r->status;
+ const char *saved_status_line = f->r->status_line;
+ f->r->status = HTTP_CONTINUE;
+ f->r->status_line = NULL;
+ ap_send_interim_response(f->r, 0);
+ AP_DEBUG_ASSERT(!f->r->expecting_100);
+ f->r->status_line = saved_status_line;
+ f->r->status = saved_status;
+ }
+ else {
+ /* https://tools.ietf.org/html/rfc7231#section-5.1.1
+ * A server MAY omit sending a 100 (Continue) response if it
+ * has already received some or all of the message body for
+ * the corresponding request [...]
+ */
+ f->r->expecting_100 = 0;
+ }
+ }
+
+ /* sanity check in case we're read twice */
+ if (ctx->eos_sent) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ return APR_SUCCESS;
+ }
+
+ do {
+ apr_brigade_cleanup(b);
+ again = 0; /* until further notice */
+
+ /* read and handle the brigade */
+ switch (ctx->state) {
+ case BODY_CHUNK:
+ case BODY_CHUNK_PART:
+ case BODY_CHUNK_EXT:
+ case BODY_CHUNK_CR:
+ case BODY_CHUNK_LF:
+ case BODY_CHUNK_END:
+ case BODY_CHUNK_END_LF: {
+
+ rv = ap_get_brigade(f->next, b, AP_MODE_GETLINE, block, 0);
+
+ /* for timeout */
+ if (block == APR_NONBLOCK_READ
+ && ((rv == APR_SUCCESS && APR_BRIGADE_EMPTY(b))
+ || (APR_STATUS_IS_EAGAIN(rv)))) {
+ return APR_EAGAIN;
+ }
+
+ if (rv == APR_EOF) {
+ return APR_INCOMPLETE;
+ }
+
+ if (rv != APR_SUCCESS) {
+ return rv;
+ }
+
+ e = APR_BRIGADE_FIRST(b);
+ while (e != APR_BRIGADE_SENTINEL(b)) {
+ const char *buffer;
+ apr_size_t len;
+
+ if (!APR_BUCKET_IS_METADATA(e)) {
+ int parsing = 0;
+
+ rv = apr_bucket_read(e, &buffer, &len, APR_BLOCK_READ);
+ if (rv == APR_SUCCESS) {
+ parsing = 1;
+ if (len > 0) {
+ ctx->seen_data = 1;
+ }
+ rv = parse_chunk_size(ctx, buffer, len,
+ f->r->server->limit_req_fieldsize, strict);
+ }
+ if (rv != APR_SUCCESS) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, rv, f->r, APLOGNO(01590)
+ "Error reading/parsing chunk %s ",
+ (APR_ENOSPC == rv) ? "(overflow)" : "");
+ if (parsing) {
+ if (rv != APR_ENOSPC) {
+ http_error = HTTP_BAD_REQUEST;
+ }
+ return bail_out_on_error(ctx, f, http_error);
+ }
+ return rv;
+ }
+ }
+
+ apr_bucket_delete(e);
+ e = APR_BRIGADE_FIRST(b);
+ }
+ again = 1; /* come around again */
+
+ if (ctx->state == BODY_CHUNK_TRAILER) {
+ /* Treat UNSET as DISABLE - trailers aren't merged by default */
+ return read_chunked_trailers(ctx, f, b,
+ conf->merge_trailers == AP_MERGE_TRAILERS_ENABLE);
+ }
+
+ break;
+ }
+ case BODY_NONE:
+ case BODY_LENGTH:
+ case BODY_CHUNK_DATA: {
+
+ /* Ensure that the caller can not go over our boundary point. */
+ if (ctx->state != BODY_NONE && ctx->remaining < readbytes) {
+ readbytes = ctx->remaining;
+ }
+ if (readbytes > 0) {
+ apr_off_t totalread;
+
+ rv = ap_get_brigade(f->next, b, mode, block, readbytes);
+
+ /* for timeout */
+ if (block == APR_NONBLOCK_READ
+ && ((rv == APR_SUCCESS && APR_BRIGADE_EMPTY(b))
+ || (APR_STATUS_IS_EAGAIN(rv)))) {
+ return APR_EAGAIN;
+ }
+
+ if (rv == APR_EOF && ctx->state != BODY_NONE
+ && ctx->remaining > 0) {
+ return APR_INCOMPLETE;
+ }
+
+ if (rv != APR_SUCCESS) {
+ return rv;
+ }
+
+ /* How many bytes did we just read? */
+ apr_brigade_length(b, 0, &totalread);
+ if (totalread > 0) {
+ ctx->seen_data = 1;
+ }
+
+ /* If this happens, we have a bucket of unknown length. Die because
+ * it means our assumptions have changed. */
+ AP_DEBUG_ASSERT(totalread >= 0);
+
+ if (ctx->state != BODY_NONE) {
+ ctx->remaining -= totalread;
+ if (ctx->remaining > 0) {
+ e = APR_BRIGADE_LAST(b);
+ if (APR_BUCKET_IS_EOS(e)) {
+ apr_bucket_delete(e);
+ return APR_INCOMPLETE;
+ }
+ }
+ else if (ctx->state == BODY_CHUNK_DATA) {
+ /* next chunk please */
+ ctx->state = BODY_CHUNK_END;
+ ctx->chunk_used = 0;
+ }
+ }
+
+ /* We have a limit in effect. */
+ if (ctx->limit) {
+ /* FIXME: Note that we might get slightly confused on
+ * chunked inputs as we'd need to compensate for the chunk
+ * lengths which may not really count. This seems to be up
+ * for interpretation.
+ */
+ ctx->limit_used += totalread;
+ if (ctx->limit < ctx->limit_used) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r,
+ APLOGNO(01591) "Read content length of "
+ "%" APR_OFF_T_FMT " is larger than the "
+ "configured limit of %" APR_OFF_T_FMT,
+ ctx->limit_used, ctx->limit);
+ return bail_out_on_error(ctx, f,
+ HTTP_REQUEST_ENTITY_TOO_LARGE);
+ }
+ }
+ }
+
+ /* If we have no more bytes remaining on a C-L request,
+ * save the caller a round trip to discover EOS.
+ */
+ if (ctx->state == BODY_LENGTH && ctx->remaining == 0) {
+ e = apr_bucket_eos_create(f->c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ ctx->eos_sent = 1;
+ }
+
+ break;
+ }
+ case BODY_CHUNK_TRAILER: {
+
+ rv = ap_get_brigade(f->next, b, mode, block, readbytes);
+
+ /* for timeout */
+ if (block == APR_NONBLOCK_READ
+ && ((rv == APR_SUCCESS && APR_BRIGADE_EMPTY(b))
+ || (APR_STATUS_IS_EAGAIN(rv)))) {
+ return APR_EAGAIN;
+ }
+
+ if (rv != APR_SUCCESS) {
+ return rv;
+ }
+
+ break;
+ }
+ default: {
+ /* Should not happen */
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, f->r, APLOGNO(02901)
+ "Unexpected body state (%i)", (int)ctx->state);
+ return APR_EGENERAL;
+ }
+ }
+
+ } while (again);
+
+ return APR_SUCCESS;
+}
+
+struct check_header_ctx {
+ request_rec *r;
+ int strict;
+};
+
+/* check a single header, to be used with apr_table_do() */
+static int check_header(struct check_header_ctx *ctx,
+ const char *name, const char **val)
+{
+ const char *pos, *end;
+ char *dst = NULL;
+
+ if (name[0] == '\0') {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, ctx->r, APLOGNO(02428)
+ "Empty response header name, aborting request");
+ return 0;
+ }
+
+ if (ctx->strict) {
+ end = ap_scan_http_token(name);
+ }
+ else {
+ end = ap_scan_vchar_obstext(name);
+ }
+ if (*end) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, ctx->r, APLOGNO(02429)
+ "Response header name '%s' contains invalid "
+ "characters, aborting request",
+ name);
+ return 0;
+ }
+
+ for (pos = *val; *pos; pos = end) {
+ end = ap_scan_http_field_content(pos);
+ if (*end) {
+ if (end[0] != CR || end[1] != LF || (end[2] != ' ' &&
+ end[2] != '\t')) {
+ ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, ctx->r, APLOGNO(02430)
+ "Response header '%s' value of '%s' contains "
+ "invalid characters, aborting request",
+ name, pos);
+ return 0;
+ }
+ if (!dst) {
+ *val = dst = apr_palloc(ctx->r->pool, strlen(*val) + 1);
+ }
+ }
+ if (dst) {
+ memcpy(dst, pos, end - pos);
+ dst += end - pos;
+ if (*end) {
+ /* skip folding and replace with a single space */
+ end += 3 + strspn(end + 3, "\t ");
+ *dst++ = ' ';
+ }
+ }
+ }
+ if (dst) {
+ *dst = '\0';
+ }
+ return 1;
+}
+
+static int check_headers_table(apr_table_t *t, struct check_header_ctx *ctx)
+{
+ const apr_array_header_t *headers = apr_table_elts(t);
+ apr_table_entry_t *header;
+ int i;
+
+ for (i = 0; i < headers->nelts; ++i) {
+ header = &APR_ARRAY_IDX(headers, i, apr_table_entry_t);
+ if (!header->key) {
+ continue;
+ }
+ if (!check_header(ctx, header->key, (const char **)&header->val)) {
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/**
+ * Check headers for HTTP conformance
+ * @return 1 if ok, 0 if bad
+ */
+static APR_INLINE int check_headers(request_rec *r)
+{
+ struct check_header_ctx ctx;
+ core_server_config *conf =
+ ap_get_core_module_config(r->server->module_config);
+
+ ctx.r = r;
+ ctx.strict = (conf->http_conformance != AP_HTTP_CONFORMANCE_UNSAFE);
+ return check_headers_table(r->headers_out, &ctx) &&
+ check_headers_table(r->err_headers_out, &ctx);
+}
+
+static int check_headers_recursion(request_rec *r)
+{
+ void *check = NULL;
+ apr_pool_userdata_get(&check, "check_headers_recursion", r->pool);
+ if (check) {
+ return 1;
+ }
+ apr_pool_userdata_setn("true", "check_headers_recursion", NULL, r->pool);
+ return 0;
+}
+
+typedef struct header_struct {
+ apr_pool_t *pool;
+ apr_bucket_brigade *bb;
+} header_struct;
+
+/* Send a single HTTP header field to the client. Note that this function
+ * is used in calls to apr_table_do(), so don't change its interface.
+ * It returns true unless there was a write error of some kind.
+ */
+static int form_header_field(header_struct *h,
+ const char *fieldname, const char *fieldval)
+{
+#if APR_CHARSET_EBCDIC
+ char *headfield;
+ apr_size_t len;
+
+ headfield = apr_pstrcat(h->pool, fieldname, ": ", fieldval, CRLF, NULL);
+ len = strlen(headfield);
+
+ ap_xlate_proto_to_ascii(headfield, len);
+ apr_brigade_write(h->bb, NULL, NULL, headfield, len);
+#else
+ struct iovec vec[4];
+ struct iovec *v = vec;
+ v->iov_base = (void *)fieldname;
+ v->iov_len = strlen(fieldname);
+ v++;
+ v->iov_base = ": ";
+ v->iov_len = sizeof(": ") - 1;
+ v++;
+ v->iov_base = (void *)fieldval;
+ v->iov_len = strlen(fieldval);
+ v++;
+ v->iov_base = CRLF;
+ v->iov_len = sizeof(CRLF) - 1;
+ apr_brigade_writev(h->bb, NULL, NULL, vec, 4);
+#endif /* !APR_CHARSET_EBCDIC */
+ return 1;
+}
+
+/* This routine is called by apr_table_do and merges all instances of
+ * the passed field values into a single array that will be further
+ * processed by some later routine. Originally intended to help split
+ * and recombine multiple Vary fields, though it is generic to any field
+ * consisting of comma/space-separated tokens.
+ */
+static int uniq_field_values(void *d, const char *key, const char *val)
+{
+ apr_array_header_t *values;
+ char *start;
+ char *e;
+ char **strpp;
+ int i;
+
+ values = (apr_array_header_t *)d;
+
+ e = apr_pstrdup(values->pool, val);
+
+ do {
+ /* Find a non-empty fieldname */
+
+ while (*e == ',' || apr_isspace(*e)) {
+ ++e;
+ }
+ if (*e == '\0') {
+ break;
+ }
+ start = e;
+ while (*e != '\0' && *e != ',' && !apr_isspace(*e)) {
+ ++e;
+ }
+ if (*e != '\0') {
+ *e++ = '\0';
+ }
+
+ /* Now add it to values if it isn't already represented.
+ * Could be replaced by a ap_array_strcasecmp() if we had one.
+ */
+ for (i = 0, strpp = (char **) values->elts; i < values->nelts;
+ ++i, ++strpp) {
+ if (*strpp && ap_cstr_casecmp(*strpp, start) == 0) {
+ break;
+ }
+ }
+ if (i == values->nelts) { /* if not found */
+ *(char **)apr_array_push(values) = start;
+ }
+ } while (*e != '\0');
+
+ return 1;
+}
+
+/*
+ * Since some clients choke violently on multiple Vary fields, or
+ * Vary fields with duplicate tokens, combine any multiples and remove
+ * any duplicates.
+ */
+static void fixup_vary(request_rec *r)
+{
+ apr_array_header_t *varies;
+
+ varies = apr_array_make(r->pool, 5, sizeof(char *));
+
+ /* Extract all Vary fields from the headers_out, separate each into
+ * its comma-separated fieldname values, and then add them to varies
+ * if not already present in the array.
+ */
+ apr_table_do(uniq_field_values, varies, r->headers_out, "Vary", NULL);
+
+ /* If we found any, replace old Vary fields with unique-ified value */
+
+ if (varies->nelts > 0) {
+ apr_table_setn(r->headers_out, "Vary",
+ apr_array_pstrcat(r->pool, varies, ','));
+ }
+}
+
+/* Send a request's HTTP response headers to the client.
+ */
+static apr_status_t send_all_header_fields(header_struct *h,
+ const request_rec *r)
+{
+ const apr_array_header_t *elts;
+ const apr_table_entry_t *t_elt;
+ const apr_table_entry_t *t_end;
+ struct iovec *vec;
+ struct iovec *vec_next;
+
+ elts = apr_table_elts(r->headers_out);
+ if (elts->nelts == 0) {
+ return APR_SUCCESS;
+ }
+ t_elt = (const apr_table_entry_t *)(elts->elts);
+ t_end = t_elt + elts->nelts;
+ vec = (struct iovec *)apr_palloc(h->pool, 4 * elts->nelts *
+ sizeof(struct iovec));
+ vec_next = vec;
+
+ /* For each field, generate
+ * name ": " value CRLF
+ */
+ do {
+ vec_next->iov_base = (void*)(t_elt->key);
+ vec_next->iov_len = strlen(t_elt->key);
+ vec_next++;
+ vec_next->iov_base = ": ";
+ vec_next->iov_len = sizeof(": ") - 1;
+ vec_next++;
+ vec_next->iov_base = (void*)(t_elt->val);
+ vec_next->iov_len = strlen(t_elt->val);
+ vec_next++;
+ vec_next->iov_base = CRLF;
+ vec_next->iov_len = sizeof(CRLF) - 1;
+ vec_next++;
+ t_elt++;
+ } while (t_elt < t_end);
+
+ if (APLOGrtrace4(r)) {
+ t_elt = (const apr_table_entry_t *)(elts->elts);
+ do {
+ ap_log_rerror(APLOG_MARK, APLOG_TRACE4, 0, r, " %s: %s",
+ ap_escape_logitem(r->pool, t_elt->key),
+ ap_escape_logitem(r->pool, t_elt->val));
+ t_elt++;
+ } while (t_elt < t_end);
+ }
+
+#if APR_CHARSET_EBCDIC
+ {
+ apr_size_t len;
+ char *tmp = apr_pstrcatv(r->pool, vec, vec_next - vec, &len);
+ ap_xlate_proto_to_ascii(tmp, len);
+ return apr_brigade_write(h->bb, NULL, NULL, tmp, len);
+ }
+#else
+ return apr_brigade_writev(h->bb, NULL, NULL, vec, vec_next - vec);
+#endif
+}
+
+/* Confirm that the status line is well-formed and matches r->status.
+ * If they don't match, a filter may have negated the status line set by a
+ * handler.
+ * Zap r->status_line if bad.
+ */
+static apr_status_t validate_status_line(request_rec *r)
+{
+ char *end;
+
+ if (r->status_line) {
+ int len = strlen(r->status_line);
+ if (len < 3
+ || apr_strtoi64(r->status_line, &end, 10) != r->status
+ || (end - 3) != r->status_line
+ || (len >= 4 && ! apr_isspace(r->status_line[3]))) {
+ r->status_line = NULL;
+ return APR_EGENERAL;
+ }
+ /* Since we passed the above check, we know that length three
+ * is equivalent to only a 3 digit numeric http status.
+ * RFC2616 mandates a trailing space, let's add it.
+ */
+ if (len == 3) {
+ r->status_line = apr_pstrcat(r->pool, r->status_line, " ", NULL);
+ return APR_EGENERAL;
+ }
+ return APR_SUCCESS;
+ }
+ return APR_EGENERAL;
+}
+
+/*
+ * Determine the protocol to use for the response. Potentially downgrade
+ * to HTTP/1.0 in some situations and/or turn off keepalives.
+ *
+ * also prepare r->status_line.
+ */
+static void basic_http_header_check(request_rec *r,
+ const char **protocol)
+{
+ apr_status_t rv;
+
+ if (r->assbackwards) {
+ /* no such thing as a response protocol */
+ return;
+ }
+
+ rv = validate_status_line(r);
+
+ if (!r->status_line) {
+ r->status_line = ap_get_status_line(r->status);
+ } else if (rv != APR_SUCCESS) {
+ /* Status line is OK but our own reason phrase
+ * would be preferred if defined
+ */
+ const char *tmp = ap_get_status_line(r->status);
+ if (!strncmp(tmp, r->status_line, 3)) {
+ r->status_line = tmp;
+ }
+ }
+
+ /* Note that we must downgrade before checking for force responses. */
+ if (r->proto_num > HTTP_VERSION(1,0)
+ && apr_table_get(r->subprocess_env, "downgrade-1.0")) {
+ r->proto_num = HTTP_VERSION(1,0);
+ }
+
+ /* kludge around broken browsers when indicated by force-response-1.0
+ */
+ if (r->proto_num == HTTP_VERSION(1,0)
+ && apr_table_get(r->subprocess_env, "force-response-1.0")) {
+ *protocol = "HTTP/1.0";
+ r->connection->keepalive = AP_CONN_CLOSE;
+ }
+ else {
+ *protocol = AP_SERVER_PROTOCOL;
+ }
+
+}
+
+/* fill "bb" with a barebones/initial HTTP response header */
+static void basic_http_header(request_rec *r, apr_bucket_brigade *bb,
+ const char *protocol)
+{
+ char *date = NULL;
+ const char *proxy_date = NULL;
+ const char *server = NULL;
+ const char *us = ap_get_server_banner();
+ header_struct h;
+ struct iovec vec[4];
+
+ if (r->assbackwards) {
+ /* there are no headers to send */
+ return;
+ }
+
+ /* Output the HTTP/1.x Status-Line and the Date and Server fields */
+
+ vec[0].iov_base = (void *)protocol;
+ vec[0].iov_len = strlen(protocol);
+ vec[1].iov_base = (void *)" ";
+ vec[1].iov_len = sizeof(" ") - 1;
+ vec[2].iov_base = (void *)(r->status_line);
+ vec[2].iov_len = strlen(r->status_line);
+ vec[3].iov_base = (void *)CRLF;
+ vec[3].iov_len = sizeof(CRLF) - 1;
+#if APR_CHARSET_EBCDIC
+ {
+ char *tmp;
+ apr_size_t len;
+ tmp = apr_pstrcatv(r->pool, vec, 4, &len);
+ ap_xlate_proto_to_ascii(tmp, len);
+ apr_brigade_write(bb, NULL, NULL, tmp, len);
+ }
+#else
+ apr_brigade_writev(bb, NULL, NULL, vec, 4);
+#endif
+
+ h.pool = r->pool;
+ h.bb = bb;
+
+ /*
+ * keep the set-by-proxy server and date headers, otherwise
+ * generate a new server header / date header
+ */
+ if (r->proxyreq != PROXYREQ_NONE) {
+ proxy_date = apr_table_get(r->headers_out, "Date");
+ if (!proxy_date) {
+ /*
+ * proxy_date needs to be const. So use date for the creation of
+ * our own Date header and pass it over to proxy_date later to
+ * avoid a compiler warning.
+ */
+ date = apr_palloc(r->pool, APR_RFC822_DATE_LEN);
+ ap_recent_rfc822_date(date, r->request_time);
+ }
+ server = apr_table_get(r->headers_out, "Server");
+ }
+ else {
+ date = apr_palloc(r->pool, APR_RFC822_DATE_LEN);
+ ap_recent_rfc822_date(date, r->request_time);
+ }
+
+ form_header_field(&h, "Date", proxy_date ? proxy_date : date );
+
+ if (!server && *us)
+ server = us;
+ if (server)
+ form_header_field(&h, "Server", server);
+
+ if (APLOGrtrace3(r)) {
+ ap_log_rerror(APLOG_MARK, APLOG_TRACE3, 0, r,
+ "Response sent with status %d%s",
+ r->status,
+ APLOGrtrace4(r) ? ", headers:" : "");
+
+ /*
+ * Date and Server are less interesting, use TRACE5 for them while
+ * using TRACE4 for the other headers.
+ */
+ ap_log_rerror(APLOG_MARK, APLOG_TRACE5, 0, r, " Date: %s",
+ proxy_date ? proxy_date : date );
+ if (server)
+ ap_log_rerror(APLOG_MARK, APLOG_TRACE5, 0, r, " Server: %s",
+ server);
+ }
+
+
+ /* unset so we don't send them again */
+ apr_table_unset(r->headers_out, "Date"); /* Avoid bogosity */
+ if (server) {
+ apr_table_unset(r->headers_out, "Server");
+ }
+}
+
+AP_DECLARE(void) ap_basic_http_header(request_rec *r, apr_bucket_brigade *bb)
+{
+ const char *protocol = NULL;
+
+ basic_http_header_check(r, &protocol);
+ basic_http_header(r, bb, protocol);
+}
+
+static void terminate_header(apr_bucket_brigade *bb)
+{
+ char crlf[] = CRLF;
+ apr_size_t buflen;
+
+ buflen = strlen(crlf);
+ ap_xlate_proto_to_ascii(crlf, buflen);
+ apr_brigade_write(bb, NULL, NULL, crlf, buflen);
+}
+
+AP_DECLARE_NONSTD(int) ap_send_http_trace(request_rec *r)
+{
+ core_server_config *conf;
+ int rv;
+ apr_bucket_brigade *bb;
+ header_struct h;
+ apr_bucket *b;
+ int body;
+ char *bodyread = NULL, *bodyoff;
+ apr_size_t bodylen = 0;
+ apr_size_t bodybuf;
+ long res = -1; /* init to avoid gcc -Wall warning */
+
+ if (r->method_number != M_TRACE) {
+ return DECLINED;
+ }
+
+ /* Get the original request */
+ while (r->prev) {
+ r = r->prev;
+ }
+ conf = ap_get_core_module_config(r->server->module_config);
+
+ if (conf->trace_enable == AP_TRACE_DISABLE) {
+ apr_table_setn(r->notes, "error-notes",
+ "TRACE denied by server configuration");
+ return HTTP_METHOD_NOT_ALLOWED;
+ }
+
+ if (conf->trace_enable == AP_TRACE_EXTENDED)
+ /* XXX: should be = REQUEST_CHUNKED_PASS */
+ body = REQUEST_CHUNKED_DECHUNK;
+ else
+ body = REQUEST_NO_BODY;
+
+ if ((rv = ap_setup_client_block(r, body))) {
+ if (rv == HTTP_REQUEST_ENTITY_TOO_LARGE)
+ apr_table_setn(r->notes, "error-notes",
+ "TRACE with a request body is not allowed");
+ return rv;
+ }
+
+ if (ap_should_client_block(r)) {
+
+ if (r->remaining > 0) {
+ if (r->remaining > 65536) {
+ apr_table_setn(r->notes, "error-notes",
+ "Extended TRACE request bodies cannot exceed 64k\n");
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+ /* always 32 extra bytes to catch chunk header exceptions */
+ bodybuf = (apr_size_t)r->remaining + 32;
+ }
+ else {
+ /* Add an extra 8192 for chunk headers */
+ bodybuf = 73730;
+ }
+
+ bodyoff = bodyread = apr_palloc(r->pool, bodybuf);
+
+ /* only while we have enough for a chunked header */
+ while ((!bodylen || bodybuf >= 32) &&
+ (res = ap_get_client_block(r, bodyoff, bodybuf)) > 0) {
+ bodylen += res;
+ bodybuf -= res;
+ bodyoff += res;
+ }
+ if (res > 0 && bodybuf < 32) {
+ /* discard_rest_of_request_body into our buffer */
+ while (ap_get_client_block(r, bodyread, bodylen) > 0)
+ ;
+ apr_table_setn(r->notes, "error-notes",
+ "Extended TRACE request bodies cannot exceed 64k\n");
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+
+ if (res < 0) {
+ return HTTP_BAD_REQUEST;
+ }
+ }
+
+ ap_set_content_type(r, "message/http");
+
+ /* Now we recreate the request, and echo it back */
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+#if APR_CHARSET_EBCDIC
+ {
+ char *tmp;
+ apr_size_t len;
+ len = strlen(r->the_request);
+ tmp = apr_pmemdup(r->pool, r->the_request, len);
+ ap_xlate_proto_to_ascii(tmp, len);
+ apr_brigade_putstrs(bb, NULL, NULL, tmp, CRLF_ASCII, NULL);
+ }
+#else
+ apr_brigade_putstrs(bb, NULL, NULL, r->the_request, CRLF, NULL);
+#endif
+ h.pool = r->pool;
+ h.bb = bb;
+ apr_table_do((int (*) (void *, const char *, const char *))
+ form_header_field, (void *) &h, r->headers_in, NULL);
+ apr_brigade_puts(bb, NULL, NULL, CRLF_ASCII);
+
+ /* If configured to accept a body, echo the body */
+ if (bodylen) {
+ b = apr_bucket_pool_create(bodyread, bodylen,
+ r->pool, bb->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(bb, b);
+ }
+
+ ap_pass_brigade(r->output_filters, bb);
+
+ return DONE;
+}
+
+typedef struct header_filter_ctx {
+ int headers_sent;
+} header_filter_ctx;
+
+AP_CORE_DECLARE_NONSTD(apr_status_t) ap_http_header_filter(ap_filter_t *f,
+ apr_bucket_brigade *b)
+{
+ request_rec *r = f->r;
+ conn_rec *c = r->connection;
+ const char *clheader;
+ int header_only = (r->header_only || AP_STATUS_IS_HEADER_ONLY(r->status));
+ const char *protocol = NULL;
+ apr_bucket *e;
+ apr_bucket_brigade *b2;
+ header_struct h;
+ header_filter_ctx *ctx = f->ctx;
+ const char *ctype;
+ ap_bucket_error *eb = NULL;
+ apr_status_t rv = APR_SUCCESS;
+ int recursive_error = 0;
+
+ AP_DEBUG_ASSERT(!r->main);
+
+ if (!ctx) {
+ ctx = f->ctx = apr_pcalloc(r->pool, sizeof(header_filter_ctx));
+ }
+ else if (ctx->headers_sent) {
+ /* Eat body if response must not have one. */
+ if (header_only) {
+ /* Still next filters may be waiting for EOS, so pass it (alone)
+ * when encountered and be done with this filter.
+ */
+ e = APR_BRIGADE_LAST(b);
+ if (e != APR_BRIGADE_SENTINEL(b) && APR_BUCKET_IS_EOS(e)) {
+ APR_BUCKET_REMOVE(e);
+ apr_brigade_cleanup(b);
+ APR_BRIGADE_INSERT_HEAD(b, e);
+ ap_remove_output_filter(f);
+ rv = ap_pass_brigade(f->next, b);
+ }
+ apr_brigade_cleanup(b);
+ return rv;
+ }
+ }
+
+ for (e = APR_BRIGADE_FIRST(b);
+ e != APR_BRIGADE_SENTINEL(b);
+ e = APR_BUCKET_NEXT(e))
+ {
+ if (AP_BUCKET_IS_ERROR(e) && !eb) {
+ eb = e->data;
+ continue;
+ }
+ /*
+ * If we see an EOC bucket it is a signal that we should get out
+ * of the way doing nothing.
+ */
+ if (AP_BUCKET_IS_EOC(e)) {
+ ap_remove_output_filter(f);
+ return ap_pass_brigade(f->next, b);
+ }
+ }
+
+ if (!ctx->headers_sent && !check_headers(r)) {
+ /* We may come back here from ap_die() below,
+ * so clear anything from this response.
+ */
+ apr_table_clear(r->headers_out);
+ apr_table_clear(r->err_headers_out);
+ apr_brigade_cleanup(b);
+
+ /* Don't recall ap_die() if we come back here (from its own internal
+ * redirect or error response), otherwise we can end up in infinite
+ * recursion; better fall through with 500, minimal headers and an
+ * empty body (EOS only).
+ */
+ if (!check_headers_recursion(r)) {
+ ap_die(HTTP_INTERNAL_SERVER_ERROR, r);
+ return AP_FILTER_ERROR;
+ }
+ r->status = HTTP_INTERNAL_SERVER_ERROR;
+ e = ap_bucket_eoc_create(c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ e = apr_bucket_eos_create(c->bucket_alloc);
+ APR_BRIGADE_INSERT_TAIL(b, e);
+ r->content_type = r->content_encoding = NULL;
+ r->content_languages = NULL;
+ ap_set_content_length(r, 0);
+ recursive_error = 1;
+ }
+ else if (eb) {
+ int status;
+ status = eb->status;
+ apr_brigade_cleanup(b);
+ ap_die(status, r);
+ return AP_FILTER_ERROR;
+ }
+
+ if (r->assbackwards) {
+ r->sent_bodyct = 1;
+ ap_remove_output_filter(f);
+ rv = ap_pass_brigade(f->next, b);
+ goto out;
+ }
+
+ /*
+ * Now that we are ready to send a response, we need to combine the two
+ * header field tables into a single table. If we don't do this, our
+ * later attempts to set or unset a given fieldname might be bypassed.
+ */
+ if (!apr_is_empty_table(r->err_headers_out)) {
+ r->headers_out = apr_table_overlay(r->pool, r->err_headers_out,
+ r->headers_out);
+ }
+
+ /*
+ * Remove the 'Vary' header field if the client can't handle it.
+ * Since this will have nasty effects on HTTP/1.1 caches, force
+ * the response into HTTP/1.0 mode.
+ *
+ * Note: the force-response-1.0 should come before the call to
+ * basic_http_header_check()
+ */
+ if (apr_table_get(r->subprocess_env, "force-no-vary") != NULL) {
+ apr_table_unset(r->headers_out, "Vary");
+ r->proto_num = HTTP_VERSION(1,0);
+ apr_table_setn(r->subprocess_env, "force-response-1.0", "1");
+ }
+ else {
+ fixup_vary(r);
+ }
+
+ /*
+ * Now remove any ETag response header field if earlier processing
+ * says so (such as a 'FileETag None' directive).
+ */
+ if (apr_table_get(r->notes, "no-etag") != NULL) {
+ apr_table_unset(r->headers_out, "ETag");
+ }
+
+ /* determine the protocol and whether we should use keepalives. */
+ basic_http_header_check(r, &protocol);
+ ap_set_keepalive(r);
+
+ if (AP_STATUS_IS_HEADER_ONLY(r->status)) {
+ apr_table_unset(r->headers_out, "Transfer-Encoding");
+ apr_table_unset(r->headers_out, "Content-Length");
+ r->content_type = r->content_encoding = NULL;
+ r->content_languages = NULL;
+ r->clength = r->chunked = 0;
+ }
+ else if (r->chunked) {
+ apr_table_mergen(r->headers_out, "Transfer-Encoding", "chunked");
+ apr_table_unset(r->headers_out, "Content-Length");
+ }
+
+ ctype = ap_make_content_type(r, r->content_type);
+ if (ctype) {
+ apr_table_setn(r->headers_out, "Content-Type", ctype);
+ }
+
+ if (r->content_encoding) {
+ apr_table_setn(r->headers_out, "Content-Encoding",
+ r->content_encoding);
+ }
+
+ if (!apr_is_empty_array(r->content_languages)) {
+ int i;
+ char *token;
+ char **languages = (char **)(r->content_languages->elts);
+ const char *field = apr_table_get(r->headers_out, "Content-Language");
+
+ while (field && (token = ap_get_list_item(r->pool, &field)) != NULL) {
+ for (i = 0; i < r->content_languages->nelts; ++i) {
+ if (!ap_cstr_casecmp(token, languages[i]))
+ break;
+ }
+ if (i == r->content_languages->nelts) {
+ *((char **) apr_array_push(r->content_languages)) = token;
+ }
+ }
+
+ field = apr_array_pstrcat(r->pool, r->content_languages, ',');
+ apr_table_setn(r->headers_out, "Content-Language", field);
+ }
+
+ /*
+ * Control cachability for non-cacheable responses if not already set by
+ * some other part of the server configuration.
+ */
+ if (r->no_cache && !apr_table_get(r->headers_out, "Expires")) {
+ char *date = apr_palloc(r->pool, APR_RFC822_DATE_LEN);
+ ap_recent_rfc822_date(date, r->request_time);
+ apr_table_addn(r->headers_out, "Expires", date);
+ }
+
+ /* This is a hack, but I can't find anyway around it. The idea is that
+ * we don't want to send out 0 Content-Lengths if it is a head request.
+ * This happens when modules try to outsmart the server, and return
+ * if they see a HEAD request. Apache 1.3 handlers were supposed to
+ * just return in that situation, and the core handled the HEAD. In
+ * 2.0, if a handler returns, then the core sends an EOS bucket down
+ * the filter stack, and the content-length filter computes a C-L of
+ * zero and that gets put in the headers, and we end up sending a
+ * zero C-L to the client. We can't just remove the C-L filter,
+ * because well behaved 2.0 handlers will send their data down the stack,
+ * and we will compute a real C-L for the head request. RBB
+ */
+ if (r->header_only
+ && (clheader = apr_table_get(r->headers_out, "Content-Length"))
+ && !strcmp(clheader, "0")) {
+ apr_table_unset(r->headers_out, "Content-Length");
+ }
+
+ b2 = apr_brigade_create(r->pool, c->bucket_alloc);
+ basic_http_header(r, b2, protocol);
+
+ h.pool = r->pool;
+ h.bb = b2;
+
+ send_all_header_fields(&h, r);
+
+ terminate_header(b2);
+
+ if (header_only) {
+ e = APR_BRIGADE_LAST(b);
+ if (e != APR_BRIGADE_SENTINEL(b) && APR_BUCKET_IS_EOS(e)) {
+ APR_BUCKET_REMOVE(e);
+ APR_BRIGADE_INSERT_TAIL(b2, e);
+ ap_remove_output_filter(f);
+ }
+ apr_brigade_cleanup(b);
+ }
+
+ rv = ap_pass_brigade(f->next, b2);
+ apr_brigade_cleanup(b2);
+ ctx->headers_sent = 1;
+
+ if (rv != APR_SUCCESS || header_only) {
+ goto out;
+ }
+
+ r->sent_bodyct = 1; /* Whatever follows is real body stuff... */
+
+ if (r->chunked) {
+ /* We can't add this filter until we have already sent the headers.
+ * If we add it before this point, then the headers will be chunked
+ * as well, and that is just wrong.
+ */
+ ap_add_output_filter("CHUNK", NULL, r, r->connection);
+ }
+
+ /* Don't remove this filter until after we have added the CHUNK filter.
+ * Otherwise, f->next won't be the CHUNK filter and thus the first
+ * brigade won't be chunked properly.
+ */
+ ap_remove_output_filter(f);
+ rv = ap_pass_brigade(f->next, b);
+out:
+ if (recursive_error) {
+ return AP_FILTER_ERROR;
+ }
+ return rv;
+}
+
+/*
+ * Map specific APR codes returned by the filter stack to HTTP error
+ * codes, or the default status code provided. Use it as follows:
+ *
+ * return ap_map_http_request_error(rv, HTTP_BAD_REQUEST);
+ *
+ * If the filter has already handled the error, AP_FILTER_ERROR will
+ * be returned, which is cleanly passed through.
+ *
+ * These mappings imply that the filter stack is reading from the
+ * downstream client, the proxy will map these codes differently.
+ */
+AP_DECLARE(int) ap_map_http_request_error(apr_status_t rv, int status)
+{
+ switch (rv) {
+ case AP_FILTER_ERROR:
+ return AP_FILTER_ERROR;
+
+ case APR_ENOSPC:
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+
+ case APR_ENOTIMPL:
+ return HTTP_NOT_IMPLEMENTED;
+
+ case APR_TIMEUP:
+ case APR_ETIMEDOUT:
+ return HTTP_REQUEST_TIME_OUT;
+
+ default:
+ return status;
+ }
+}
+
+/* In HTTP/1.1, any method can have a body. However, most GET handlers
+ * wouldn't know what to do with a request body if they received one.
+ * This helper routine tests for and reads any message body in the request,
+ * simply discarding whatever it receives. We need to do this because
+ * failing to read the request body would cause it to be interpreted
+ * as the next request on a persistent connection.
+ *
+ * Since we return an error status if the request is malformed, this
+ * routine should be called at the beginning of a no-body handler, e.g.,
+ *
+ * if ((retval = ap_discard_request_body(r)) != OK) {
+ * return retval;
+ * }
+ */
+AP_DECLARE(int) ap_discard_request_body(request_rec *r)
+{
+ int rc = OK;
+ conn_rec *c = r->connection;
+ apr_bucket_brigade *bb;
+
+ /* Sometimes we'll get in a state where the input handling has
+ * detected an error where we want to drop the connection, so if
+ * that's the case, don't read the data as that is what we're trying
+ * to avoid.
+ *
+ * This function is also a no-op on a subrequest.
+ */
+ if (r->main || c->keepalive == AP_CONN_CLOSE) {
+ return OK;
+ }
+ if (ap_status_drops_connection(r->status)) {
+ c->keepalive = AP_CONN_CLOSE;
+ return OK;
+ }
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ for (;;) {
+ apr_status_t rv;
+
+ rv = ap_get_brigade(r->input_filters, bb, AP_MODE_READBYTES,
+ APR_BLOCK_READ, HUGE_STRING_LEN);
+ if (rv != APR_SUCCESS) {
+ rc = ap_map_http_request_error(rv, HTTP_BAD_REQUEST);
+ goto cleanup;
+ }
+
+ while (!APR_BRIGADE_EMPTY(bb)) {
+ apr_bucket *b = APR_BRIGADE_FIRST(bb);
+
+ if (APR_BUCKET_IS_EOS(b)) {
+ goto cleanup;
+ }
+
+ /* There is no need to read empty or metadata buckets or
+ * buckets of known length, but we MUST read buckets of
+ * unknown length in order to exhaust them.
+ */
+ if (b->length == (apr_size_t)-1) {
+ apr_size_t len;
+ const char *data;
+
+ rv = apr_bucket_read(b, &data, &len, APR_BLOCK_READ);
+ if (rv != APR_SUCCESS) {
+ rc = HTTP_BAD_REQUEST;
+ goto cleanup;
+ }
+ }
+
+ apr_bucket_delete(b);
+ }
+ }
+
+cleanup:
+ apr_brigade_cleanup(bb);
+ if (rc != OK) {
+ c->keepalive = AP_CONN_CLOSE;
+ }
+ return rc;
+}
+
+/* Here we deal with getting the request message body from the client.
+ * Whether or not the request contains a body is signaled by the presence
+ * of a non-zero Content-Length or by a Transfer-Encoding: chunked.
+ *
+ * Note that this is more complicated than it was in Apache 1.1 and prior
+ * versions, because chunked support means that the module does less.
+ *
+ * The proper procedure is this:
+ *
+ * 1. Call ap_setup_client_block() near the beginning of the request
+ * handler. This will set up all the necessary properties, and will
+ * return either OK, or an error code. If the latter, the module should
+ * return that error code. The second parameter selects the policy to
+ * apply if the request message indicates a body, and how a chunked
+ * transfer-coding should be interpreted. Choose one of
+ *
+ * REQUEST_NO_BODY Send 413 error if message has any body
+ * REQUEST_CHUNKED_ERROR Send 411 error if body without Content-Length
+ * REQUEST_CHUNKED_DECHUNK If chunked, remove the chunks for me.
+ * REQUEST_CHUNKED_PASS If chunked, pass the chunk headers with body.
+ *
+ * In order to use the last two options, the caller MUST provide a buffer
+ * large enough to hold a chunk-size line, including any extensions.
+ *
+ * 2. When you are ready to read a body (if any), call ap_should_client_block().
+ * This will tell the module whether or not to read input. If it is 0,
+ * the module should assume that there is no message body to read.
+ *
+ * 3. Finally, call ap_get_client_block in a loop. Pass it a buffer and its size.
+ * It will put data into the buffer (not necessarily a full buffer), and
+ * return the length of the input block. When it is done reading, it will
+ * return 0 if EOF, or -1 if there was an error.
+ * If an error occurs on input, we force an end to keepalive.
+ *
+ * This step also sends a 100 Continue response to HTTP/1.1 clients if appropriate.
+ */
+
+AP_DECLARE(int) ap_setup_client_block(request_rec *r, int read_policy)
+{
+ const char *tenc = apr_table_get(r->headers_in, "Transfer-Encoding");
+ const char *lenp = apr_table_get(r->headers_in, "Content-Length");
+ apr_off_t limit_req_body = ap_get_limit_req_body(r);
+
+ r->read_body = read_policy;
+ r->read_chunked = 0;
+ r->remaining = 0;
+
+ if (tenc) {
+ if (ap_cstr_casecmp(tenc, "chunked")) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(01592)
+ "Unknown Transfer-Encoding %s", tenc);
+ return HTTP_NOT_IMPLEMENTED;
+ }
+ if (r->read_body == REQUEST_CHUNKED_ERROR) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(01593)
+ "chunked Transfer-Encoding forbidden: %s", r->uri);
+ return (lenp) ? HTTP_BAD_REQUEST : HTTP_LENGTH_REQUIRED;
+ }
+
+ r->read_chunked = 1;
+ }
+ else if (lenp) {
+ if (!ap_parse_strict_length(&r->remaining, lenp)) {
+ r->remaining = 0;
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(01594)
+ "Invalid Content-Length '%s'", lenp);
+ return HTTP_BAD_REQUEST;
+ }
+ }
+
+ if ((r->read_body == REQUEST_NO_BODY)
+ && (r->read_chunked || (r->remaining > 0))) {
+ ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(01595)
+ "%s with body is not allowed for %s", r->method, r->uri);
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+
+ if (limit_req_body > 0 && (r->remaining > limit_req_body)) {
+ /* will be logged when the body is discarded */
+ return HTTP_REQUEST_ENTITY_TOO_LARGE;
+ }
+
+#ifdef AP_DEBUG
+ {
+ /* Make sure ap_getline() didn't leave any droppings. */
+ core_request_config *req_cfg =
+ (core_request_config *)ap_get_core_module_config(r->request_config);
+ AP_DEBUG_ASSERT(APR_BRIGADE_EMPTY(req_cfg->bb));
+ }
+#endif
+
+ return OK;
+}
+
+AP_DECLARE(int) ap_should_client_block(request_rec *r)
+{
+ /* First check if we have already read the request body */
+
+ if (r->read_length || (!r->read_chunked && (r->remaining <= 0))) {
+ return 0;
+ }
+
+ return 1;
+}
+
+/* get_client_block is called in a loop to get the request message body.
+ * This is quite simple if the client includes a content-length
+ * (the normal case), but gets messy if the body is chunked. Note that
+ * r->remaining is used to maintain state across calls and that
+ * r->read_length is the total number of bytes given to the caller
+ * across all invocations. It is messy because we have to be careful not
+ * to read past the data provided by the client, since these reads block.
+ * Returns 0 on End-of-body, -1 on error or premature chunk end.
+ *
+ */
+AP_DECLARE(long) ap_get_client_block(request_rec *r, char *buffer,
+ apr_size_t bufsiz)
+{
+ apr_status_t rv;
+ apr_bucket_brigade *bb;
+
+ if (r->remaining < 0 || (!r->read_chunked && r->remaining == 0)) {
+ return 0;
+ }
+
+ bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
+ if (bb == NULL) {
+ r->connection->keepalive = AP_CONN_CLOSE;
+ return -1;
+ }
+
+ rv = ap_get_brigade(r->input_filters, bb, AP_MODE_READBYTES,
+ APR_BLOCK_READ, bufsiz);
+
+ /* We lose the failure code here. This is why ap_get_client_block should
+ * not be used.
+ */
+ if (rv == AP_FILTER_ERROR) {
+ /* AP_FILTER_ERROR means a filter has responded already,
+ * we are DONE.
+ */
+ apr_brigade_destroy(bb);
+ return -1;
+ }
+ if (rv != APR_SUCCESS) {
+ /* if we actually fail here, we want to just return and
+ * stop trying to read data from the client.
+ */
+ r->connection->keepalive = AP_CONN_CLOSE;
+ apr_brigade_destroy(bb);
+ return -1;
+ }
+
+ /* If this fails, it means that a filter is written incorrectly and that
+ * it needs to learn how to properly handle APR_BLOCK_READ requests by
+ * returning data when requested.
+ */
+ AP_DEBUG_ASSERT(!APR_BRIGADE_EMPTY(bb));
+
+ /* Check to see if EOS in the brigade.
+ *
+ * If so, we have to leave a nugget for the *next* ap_get_client_block
+ * call to return 0.
+ */
+ if (APR_BUCKET_IS_EOS(APR_BRIGADE_LAST(bb))) {
+ if (r->read_chunked) {
+ r->remaining = -1;
+ }
+ else {
+ r->remaining = 0;
+ }
+ }
+
+ rv = apr_brigade_flatten(bb, buffer, &bufsiz);
+ if (rv != APR_SUCCESS) {
+ apr_brigade_destroy(bb);
+ return -1;
+ }
+
+ /* XXX yank me? */
+ r->read_length += bufsiz;
+
+ apr_brigade_destroy(bb);
+ return bufsiz;
+}
+
+/* Context struct for ap_http_outerror_filter */
+typedef struct {
+ int seen_eoc;
+ int first_error;
+} outerror_filter_ctx_t;
+
+/* Filter to handle any error buckets on output */
+apr_status_t ap_http_outerror_filter(ap_filter_t *f,
+ apr_bucket_brigade *b)
+{
+ request_rec *r = f->r;
+ outerror_filter_ctx_t *ctx = (outerror_filter_ctx_t *)(f->ctx);
+ apr_bucket *e;
+
+ /* Create context if none is present */
+ if (!ctx) {
+ ctx = apr_pcalloc(r->pool, sizeof(outerror_filter_ctx_t));
+ f->ctx = ctx;
+ }
+ for (e = APR_BRIGADE_FIRST(b);
+ e != APR_BRIGADE_SENTINEL(b);
+ e = APR_BUCKET_NEXT(e))
+ {
+ if (AP_BUCKET_IS_ERROR(e)) {
+ /*
+ * Start of error handling state tree. Just one condition
+ * right now :)
+ */
+ if (((ap_bucket_error *)(e->data))->status == HTTP_BAD_GATEWAY) {
+ /* stream aborted and we have not ended it yet */
+ r->connection->keepalive = AP_CONN_CLOSE;
+ }
+ /*
+ * Memorize the status code of the first error bucket for possible
+ * later use.
+ */
+ if (!ctx->first_error) {
+ ctx->first_error = ((ap_bucket_error *)(e->data))->status;
+ }
+ continue;
+ }
+ /* Detect EOC buckets and memorize this in the context. */
+ if (AP_BUCKET_IS_EOC(e)) {
+ r->connection->keepalive = AP_CONN_CLOSE;
+ ctx->seen_eoc = 1;
+ }
+ }
+ /*
+ * Remove all data buckets that are in a brigade after an EOC bucket
+ * was seen, as an EOC bucket tells us that no (further) resource
+ * and protocol data should go out to the client. OTOH meta buckets
+ * are still welcome as they might trigger needed actions down in
+ * the chain (e.g. in network filters like SSL).
+ * Remark 1: It is needed to dump ALL data buckets in the brigade
+ * since an filter in between might have inserted data
+ * buckets BEFORE the EOC bucket sent by the original
+ * sender and we do NOT want this data to be sent.
+ * Remark 2: Dumping all data buckets here does not necessarily mean
+ * that no further data is send to the client as:
+ * 1. Network filters like SSL can still be triggered via
+ * meta buckets to talk with the client e.g. for a
+ * clean shutdown.
+ * 2. There could be still data that was buffered before
+ * down in the chain that gets flushed by a FLUSH or an
+ * EOS bucket.
+ */
+ if (ctx->seen_eoc) {
+ /*
+ * Set the request status to the status of the first error bucket.
+ * This should ensure that we log an appropriate status code in
+ * the access log.
+ * We need to set r->status on each call after we noticed an EOC as
+ * data bucket generators like ap_die might have changed the status
+ * code. But we know better in this case and insist on the status
+ * code that we have seen in the error bucket.
+ */
+ if (ctx->first_error) {
+ r->status = ctx->first_error;
+ }
+ for (e = APR_BRIGADE_FIRST(b);
+ e != APR_BRIGADE_SENTINEL(b);
+ e = APR_BUCKET_NEXT(e))
+ {
+ if (!APR_BUCKET_IS_METADATA(e)) {
+ APR_BUCKET_REMOVE(e);
+ }
+ }
+ }
+
+ return ap_pass_brigade(f->next, b);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-04 03:12:07 +0000