Reset (3a4692e2) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP Apache Httpd

modules/http/byterange_filter.c

+221 −229

Changes for modules/http/byterange_filter.c: 221 added lines, 229 removed lines.
Original line number	Diff line number	Diff line
		@@ -59,232 +59,10 @@
		#define AP_DEFAULT_MAX_RANGES 200
		#endif

		#define MAX_PREALLOC_RANGES 100

		APLOG_USE_MODULE(http);

		typedef struct indexes_t {
		apr_off_t start;
		apr_off_t end;
		} indexes_t;

		/*
		* returns number of ranges OR -1 if unsatisfiable
		*/
		static int ap_set_byterange(request_rec *r, apr_off_t clength,
		apr_array_header_t *indexes, int overlaps,
		int *reversals)
		{
		const char *range;
		const char *if_range;
		const char *match;
		const char *ct;
		char cur, *new;
		apr_array_header_t *merged;
		int num_ranges = 0, unsatisfiable = 0;
		apr_off_t ostart = 0, oend = 0, sum_lengths = 0;
		int in_merge = 0;
		indexes_t *idx;
		int ranges = 1;
		const char *it;

		*overlaps = 0;
		*reversals = 0;
		if (r->assbackwards) {
		return 0;
		}

		/*
		* Check for Range request-header (HTTP/1.1) or Request-Range for
		* backwards-compatibility with second-draft Luotonen/Franks
		* byte-ranges (e.g. Netscape Navigator 2-3).
		*
		* We support this form, with Request-Range, and (farther down) we
		* send multipart/x-byteranges instead of multipart/byteranges for
		* Request-Range based requests to work around a bug in Netscape
		* Navigator 2-3 and MSIE 3.
		*/

		if (!(range = apr_table_get(r->headers_in, "Range"))) {
		range = apr_table_get(r->headers_in, "Request-Range");
		}

		if (!range \|\| strncasecmp(range, "bytes=", 6) \|\| r->status != HTTP_OK) {
		return 0;
		}

		/* is content already a single range? */
		if (apr_table_get(r->headers_out, "Content-Range")) {
		return 0;
		}

		/* is content already a multiple range? */
		if ((ct = apr_table_get(r->headers_out, "Content-Type"))
		&& (!strncasecmp(ct, "multipart/byteranges", 20)
		\|\| !strncasecmp(ct, "multipart/x-byteranges", 22))) {
		return 0;
		}

		/*
		* Check the If-Range header for Etag or Date.
		* Note that this check will return false (as required) if either
		* of the two etags are weak.
		*/
		if ((if_range = apr_table_get(r->headers_in, "If-Range"))) {
		if (if_range[0] == '"') {
		if (!(match = apr_table_get(r->headers_out, "Etag"))
		\|\| (strcmp(if_range, match) != 0)) {
		return 0;
		}
		}
		else if (!(match = apr_table_get(r->headers_out, "Last-Modified"))
		\|\| (strcmp(if_range, match) != 0)) {
		return 0;
		}
		}

		range += 6;
		it = range;
		while (*it) {
		if (*it++ == ',') {
		ranges++;
		}
		}
		it = range;
		if (ranges > MAX_PREALLOC_RANGES) {
		ranges = MAX_PREALLOC_RANGES;
		}
		*indexes = apr_array_make(r->pool, ranges, sizeof(indexes_t));
		merged = apr_array_make(r->pool, ranges, sizeof(char *));
		while ((cur = ap_getword(r->pool, &range, ','))) {
		char *dash;
		char *errp;
		apr_off_t number, start, end;

		if (!*cur)
		break;

		/*
		* Per RFC 2616 14.35.1: If there is at least one syntactically invalid
		* byte-range-spec, we must ignore the whole header.
		*/

		if (!(dash = strchr(cur, '-'))) {
		return 0;
		}

		if (dash == cur) {
		/* In the form "-5" */
		if (apr_strtoff(&number, dash+1, &errp, 10) \|\| *errp) {
		return 0;
		}
		if (number < 1) {
		return 0;
		}
		start = clength - number;
		end = clength - 1;
		}
		else {
		*dash++ = '\0';
		if (apr_strtoff(&number, cur, &errp, 10) \|\| *errp) {
		return 0;
		}
		start = number;
		if (*dash) {
		if (apr_strtoff(&number, dash, &errp, 10) \|\| *errp) {
		return 0;
		}
		end = number;
		if (start > end) {
		return 0;
		}
		}
		else { /* "5-" */
		end = clength - 1;
		}
		}

		if (start < 0) {
		start = 0;
		}
		if (start >= clength) {
		unsatisfiable = 1;
		continue;
		}
		if (end >= clength) {
		end = clength - 1;
		}

		if (!in_merge) {
		/* new set */
		ostart = start;
		oend = end;
		in_merge = 1;
		continue;
		}
		in_merge = 0;

		if (start >= ostart && end <= oend) {
		in_merge = 1;
		}

		if (start < ostart && end >= ostart-1) {
		ostart = start;
		(*reversals)++;
		in_merge = 1;
		}
		if (end >= oend && start <= oend+1 ) {
		oend = end;
		in_merge = 1;
		}

		if (in_merge) {
		(*overlaps)++;
		continue;
		} else {
		new = (char **)apr_array_push(merged);
		*new = apr_psprintf(r->pool, "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT,
		ostart, oend);
		idx = (indexes_t )apr_array_push(indexes);
		idx->start = ostart;
		idx->end = oend;
		sum_lengths += oend - ostart + 1;
		/* new set again */
		in_merge = 1;
		ostart = start;
		oend = end;
		num_ranges++;
		}
		}

		if (in_merge) {
		new = (char **)apr_array_push(merged);
		*new = apr_psprintf(r->pool, "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT,
		ostart, oend);
		idx = (indexes_t )apr_array_push(indexes);
		idx->start = ostart;
		idx->end = oend;
		sum_lengths += oend - ostart + 1;
		num_ranges++;
		}
		else if (num_ranges == 0 && unsatisfiable) {
		/* If all ranges are unsatisfiable, we should return 416 */
		return -1;
		}
		if (sum_lengths >= clength) {
		ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r,
		"Sum of ranges not smaller than file, ignoring.");
		return 0;
		}

		r->status = HTTP_PARTIAL_CONTENT;
		r->range = apr_array_pstrcat(r->pool, merged, ',');
		ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
		"Range: %s \| %s (%d : %d : %"APR_OFF_T_FMT")",
		it, r->range, overlaps, reversals, clength);

		return num_ranges;
		}
		apr_array_header_t **indexes);

		/*
		* Here we try to be compatible with clients that want multipart/x-byteranges
		@@ -302,6 +80,7 @@ static int use_range_x(request_rec *r)
		}

		#define BYTERANGE_FMT "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT "/%" APR_OFF_T_FMT
		#define MAX_PREALLOC_RANGES 100

		static apr_status_t copy_brigade_range(apr_bucket_brigade *bb,
		apr_bucket_brigade *bbout,
		@@ -402,6 +181,11 @@ static apr_status_t copy_brigade_range(apr_bucket_brigade *bb,
		return APR_SUCCESS;
		}

		typedef struct indexes_t {
		apr_off_t start;
		apr_off_t end;
		} indexes_t;

		static int get_max_ranges(request_rec *r) {
		core_dir_config *core_conf = ap_get_core_module_config(r->per_dir_config);
		if (core_conf->max_ranges >= 0 \|\| core_conf->max_ranges == AP_MAXRANGES_UNLIMITED) {
		@@ -446,12 +230,8 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
		indexes_t *idx;
		int i;
		int original_status;
		int overlaps = 0;
		int reversals = 0;
		int max_ranges;
		core_dir_config *core_conf = ap_get_core_module_config(r->per_dir_config);
		int max_ranges = get_max_ranges(r);

		max_ranges = (core_conf->max_ranges == -1 ? DEFAULT_MAX_RANGES : core_conf->max_ranges);
		/*
		* Iterate through the brigade until reaching EOS or a bucket with
		* unknown length.
		@@ -475,7 +255,7 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
		}

		original_status = r->status;
		num_ranges = ap_set_byterange(r, clength, &indexes, &overlaps, &reversals);
		num_ranges = ap_set_byterange(r, clength, &indexes);

		/* We have nothing to do, get out of the way. */
		if (num_ranges == 0 \|\| (max_ranges >= 0 && num_ranges > max_ranges)) {
		@@ -601,3 +381,215 @@ AP_CORE_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f,
		return ap_pass_brigade(f->next, bsend);
		}

		static int ap_set_byterange(request_rec *r, apr_off_t clength,
		apr_array_header_t **indexes)
		{
		const char *range;
		const char *if_range;
		const char *match;
		const char *ct;
		char cur, *new;
		apr_array_header_t *merged;
		int num_ranges = 0, unsatisfiable = 0;
		apr_off_t ostart = 0, oend = 0, sum_lengths = 0;
		int in_merge = 0;
		indexes_t *idx;
		int overlaps = 0, reversals = 0;
		int ranges = 1;
		const char *it;

		if (r->assbackwards) {
		return 0;
		}

		/*
		* Check for Range request-header (HTTP/1.1) or Request-Range for
		* backwards-compatibility with second-draft Luotonen/Franks
		* byte-ranges (e.g. Netscape Navigator 2-3).
		*
		* We support this form, with Request-Range, and (farther down) we
		* send multipart/x-byteranges instead of multipart/byteranges for
		* Request-Range based requests to work around a bug in Netscape
		* Navigator 2-3 and MSIE 3.
		*/

		if (!(range = apr_table_get(r->headers_in, "Range"))) {
		range = apr_table_get(r->headers_in, "Request-Range");
		}

		if (!range \|\| strncasecmp(range, "bytes=", 6) \|\| r->status != HTTP_OK) {
		return 0;
		}

		/* is content already a single range? */
		if (apr_table_get(r->headers_out, "Content-Range")) {
		return 0;
		}

		/* is content already a multiple range? */
		if ((ct = apr_table_get(r->headers_out, "Content-Type"))
		&& (!strncasecmp(ct, "multipart/byteranges", 20)
		\|\| !strncasecmp(ct, "multipart/x-byteranges", 22))) {
		return 0;
		}

		/*
		* Check the If-Range header for Etag or Date.
		* Note that this check will return false (as required) if either
		* of the two etags are weak.
		*/
		if ((if_range = apr_table_get(r->headers_in, "If-Range"))) {
		if (if_range[0] == '"') {
		if (!(match = apr_table_get(r->headers_out, "Etag"))
		\|\| (strcmp(if_range, match) != 0)) {
		return 0;
		}
		}
		else if (!(match = apr_table_get(r->headers_out, "Last-Modified"))
		\|\| (strcmp(if_range, match) != 0)) {
		return 0;
		}
		}

		range += 6;
		it = range;
		while (*it) {
		if (*it++ == ',') {
		ranges++;
		}
		}
		it = range;
		if (ranges > MAX_PREALLOC_RANGES) {
		ranges = MAX_PREALLOC_RANGES;
		}
		*indexes = apr_array_make(r->pool, ranges, sizeof(indexes_t));
		merged = apr_array_make(r->pool, ranges, sizeof(char *));
		while ((cur = ap_getword(r->pool, &range, ','))) {
		char *dash;
		char *errp;
		apr_off_t number, start, end;

		if (!*cur)
		break;

		/*
		* Per RFC 2616 14.35.1: If there is at least one syntactically invalid
		* byte-range-spec, we must ignore the whole header.
		*/

		if (!(dash = strchr(cur, '-'))) {
		return 0;
		}

		if (dash == cur) {
		/* In the form "-5" */
		if (apr_strtoff(&number, dash+1, &errp, 10) \|\| *errp) {
		return 0;
		}
		if (number < 1) {
		return 0;
		}
		start = clength - number;
		end = clength - 1;
		}
		else {
		*dash++ = '\0';
		if (apr_strtoff(&number, cur, &errp, 10) \|\| *errp) {
		return 0;
		}
		start = number;
		if (*dash) {
		if (apr_strtoff(&number, dash, &errp, 10) \|\| *errp) {
		return 0;
		}
		end = number;
		if (start > end) {
		return 0;
		}
		}
		else { /* "5-" */
		end = clength - 1;
		}
		}

		if (start < 0) {
		start = 0;
		}
		if (start >= clength) {
		unsatisfiable = 1;
		continue;
		}
		if (end >= clength) {
		end = clength - 1;
		}

		if (!in_merge) {
		/* new set */
		ostart = start;
		oend = end;
		in_merge = 1;
		continue;
		}
		in_merge = 0;

		if (start >= ostart && end <= oend) {
		in_merge = 1;
		}

		if (start < ostart && end >= ostart-1) {
		ostart = start;
		reversals++;
		in_merge = 1;
		}
		if (end >= oend && start <= oend+1 ) {
		oend = end;
		in_merge = 1;
		}

		if (in_merge) {
		overlaps++;
		continue;
		} else {
		new = (char **)apr_array_push(merged);
		*new = apr_psprintf(r->pool, "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT,
		ostart, oend);
		idx = (indexes_t )apr_array_push(indexes);
		idx->start = ostart;
		idx->end = oend;
		sum_lengths += oend - ostart + 1;
		/* new set again */
		in_merge = 1;
		ostart = start;
		oend = end;
		num_ranges++;
		}
		}

		if (in_merge) {
		new = (char **)apr_array_push(merged);
		*new = apr_psprintf(r->pool, "%" APR_OFF_T_FMT "-%" APR_OFF_T_FMT,
		ostart, oend);
		idx = (indexes_t )apr_array_push(indexes);
		idx->start = ostart;
		idx->end = oend;
		sum_lengths += oend - ostart + 1;
		num_ranges++;
		}
		else if (num_ranges == 0 && unsatisfiable) {
		/* If all ranges are unsatisfiable, we should return 416 */
		return -1;
		}
		if (sum_lengths >= clength) {
		ap_log_rerror(APLOG_MARK, APLOG_TRACE1, 0, r,
		"Sum of ranges not smaller than file, ignoring.");
		return 0;
		}

		r->status = HTTP_PARTIAL_CONTENT;
		r->range = apr_array_pstrcat(r->pool, merged, ',');
		ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
		"Range: %s \| %s (%d : %d : %"APR_OFF_T_FMT")",
		it, r->range, overlaps, reversals, clength);

		return num_ranges;
		}