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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 12:18:05 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 12:18:05 +0000
commitb46aad6df449445a9fc4aa7b32bd40005438e3f7 (patch)
tree751aa858ca01f35de800164516b298887382919d /src/uri_normalizer.c
parentInitial commit. (diff)
downloadhaproxy-b46aad6df449445a9fc4aa7b32bd40005438e3f7.tar.xz
haproxy-b46aad6df449445a9fc4aa7b32bd40005438e3f7.zip
Adding upstream version 2.9.5.upstream/2.9.5
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/uri_normalizer.c')
-rw-r--r--src/uri_normalizer.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/src/uri_normalizer.c b/src/uri_normalizer.c
new file mode 100644
index 0000000..bc793f2
--- /dev/null
+++ b/src/uri_normalizer.c
@@ -0,0 +1,467 @@
+/*
+ * HTTP request URI normalization.
+ *
+ * Copyright 2021 Tim Duesterhus <tim@bastelstu.be>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <import/ist.h>
+
+#include <haproxy/api.h>
+#include <haproxy/buf.h>
+#include <haproxy/chunk.h>
+#include <haproxy/tools.h>
+#include <haproxy/uri_normalizer.h>
+
+/* Encodes '#' as '%23'. */
+enum uri_normalizer_err uri_normalizer_fragment_encode(const struct ist input, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist output = *dst;
+
+ struct ist scanner = input;
+
+ while (istlen(scanner)) {
+ const struct ist before_hash = istsplit(&scanner, '#');
+
+ if (istcat(&output, before_hash, size) < 0) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ if (istend(before_hash) != istend(scanner)) {
+ if (istcat(&output, ist("%23"), size) < 0) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+ }
+ }
+
+ *dst = output;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Returns 1 if the given character is part of the 'unreserved' set in the
+ * RFC 3986 ABNF.
+ * Returns 0 if not.
+ */
+static int is_unreserved_character(unsigned char c)
+{
+ switch (c) {
+ case 'A'...'Z': /* ALPHA */
+ case 'a'...'z': /* ALPHA */
+ case '0'...'9': /* DIGIT */
+ case '-':
+ case '.':
+ case '_':
+ case '~':
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+/* Decodes percent encoded characters that are part of the 'unreserved' set.
+ *
+ * RFC 3986, section 2.3:
+ * > URIs that differ in the replacement of an unreserved character with
+ * > its corresponding percent-encoded US-ASCII octet are equivalent [...]
+ * > when found in a URI, should be decoded to their corresponding unreserved
+ * > characters by URI normalizers.
+ *
+ * If `strict` is set to 0 then percent characters that are not followed by a
+ * hexadecimal digit are returned as-is without performing any decoding.
+ * If `strict` is set to 1 then `URI_NORMALIZER_ERR_INVALID_INPUT` is returned
+ * for invalid sequences.
+ */
+enum uri_normalizer_err uri_normalizer_percent_decode_unreserved(const struct ist input, int strict, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist output = *dst;
+
+ struct ist scanner = input;
+
+ /* The output will either be shortened or have the same length. */
+ if (size < istlen(input)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ while (istlen(scanner)) {
+ const char current = istshift(&scanner);
+
+ if (current == '%') {
+ if (istlen(scanner) >= 2) {
+ if (ishex(istptr(scanner)[0]) && ishex(istptr(scanner)[1])) {
+ char hex1, hex2, c;
+
+ hex1 = istshift(&scanner);
+ hex2 = istshift(&scanner);
+ c = (hex2i(hex1) << 4) + hex2i(hex2);
+
+ if (is_unreserved_character(c)) {
+ output = __istappend(output, c);
+ }
+ else {
+ output = __istappend(output, current);
+ output = __istappend(output, hex1);
+ output = __istappend(output, hex2);
+ }
+
+ continue;
+ }
+ }
+
+ if (strict) {
+ err = URI_NORMALIZER_ERR_INVALID_INPUT;
+ goto fail;
+ }
+ else {
+ output = __istappend(output, current);
+ }
+ }
+ else {
+ output = __istappend(output, current);
+ }
+ }
+
+ *dst = output;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Uppercases letters used in percent encoding.
+ *
+ * If `strict` is set to 0 then percent characters that are not followed by a
+ * hexadecimal digit are returned as-is without modifying the following letters.
+ * If `strict` is set to 1 then `URI_NORMALIZER_ERR_INVALID_INPUT` is returned
+ * for invalid sequences.
+ */
+enum uri_normalizer_err uri_normalizer_percent_upper(const struct ist input, int strict, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist output = *dst;
+
+ struct ist scanner = input;
+
+ /* The output will have the same length. */
+ if (size < istlen(input)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ while (istlen(scanner)) {
+ const char current = istshift(&scanner);
+
+ if (current == '%') {
+ if (istlen(scanner) >= 2) {
+ if (ishex(istptr(scanner)[0]) && ishex(istptr(scanner)[1])) {
+ output = __istappend(output, current);
+ output = __istappend(output, toupper(istshift(&scanner)));
+ output = __istappend(output, toupper(istshift(&scanner)));
+ continue;
+ }
+ }
+
+ if (strict) {
+ err = URI_NORMALIZER_ERR_INVALID_INPUT;
+ goto fail;
+ }
+ else {
+ output = __istappend(output, current);
+ }
+ }
+ else {
+ output = __istappend(output, current);
+ }
+ }
+
+ *dst = output;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Removes `/./` from the given path. */
+enum uri_normalizer_err uri_normalizer_path_dot(const struct ist path, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist newpath = *dst;
+
+ struct ist scanner = path;
+
+ /* The path will either be shortened or have the same length. */
+ if (size < istlen(path)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ while (istlen(scanner) > 0) {
+ const struct ist segment = istsplit(&scanner, '/');
+
+ if (!isteq(segment, ist("."))) {
+ if (istcat(&newpath, segment, size) < 0) {
+ /* This is impossible, because we checked the size of the destination buffer. */
+ my_unreachable();
+ err = URI_NORMALIZER_ERR_INTERNAL_ERROR;
+ goto fail;
+ }
+
+ if (istend(segment) != istend(scanner))
+ newpath = __istappend(newpath, '/');
+ }
+ }
+
+ *dst = newpath;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Merges `/../` with preceding path segments.
+ *
+ * If `full` is set to `0` then `/../` will be printed at the start of the resulting
+ * path if the number of `/../` exceeds the number of other segments. If `full` is
+ * set to `1` these will not be printed.
+ */
+enum uri_normalizer_err uri_normalizer_path_dotdot(const struct ist path, int full, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ char * const tail = istptr(*dst) + size;
+ char *head = tail;
+
+ ssize_t offset = istlen(path) - 1;
+
+ int up = 0;
+
+ /* The path will either be shortened or have the same length. */
+ if (size < istlen(path)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ /* Handle `/..` at the end of the path without a trailing slash. */
+ if (offset >= 2 && istmatch(istadv(path, offset - 2), ist("/.."))) {
+ up++;
+ offset -= 2;
+ }
+
+ while (offset >= 0) {
+ if (offset >= 3 && istmatch(istadv(path, offset - 3), ist("/../"))) {
+ up++;
+ offset -= 3;
+ continue;
+ }
+
+ if (up > 0) {
+ /* Skip the slash. */
+ offset--;
+
+ /* First check whether we already reached the start of the path,
+ * before popping the current `/../`.
+ */
+ if (offset >= 0) {
+ up--;
+
+ /* Skip the current path segment. */
+ while (offset >= 0 && istptr(path)[offset] != '/')
+ offset--;
+ }
+ }
+ else {
+ /* Prepend the slash. */
+ *(--head) = istptr(path)[offset];
+ offset--;
+
+ /* Prepend the current path segment. */
+ while (offset >= 0 && istptr(path)[offset] != '/') {
+ *(--head) = istptr(path)[offset];
+ offset--;
+ }
+ }
+ }
+
+ if (up > 0) {
+ /* Prepend a trailing slash. */
+ *(--head) = '/';
+
+ if (!full) {
+ /* Prepend unconsumed `/..`. */
+ do {
+ *(--head) = '.';
+ *(--head) = '.';
+ *(--head) = '/';
+ up--;
+ } while (up > 0);
+ }
+ }
+
+ *dst = ist2(head, tail - head);
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Merges adjacent slashes in the given path. */
+enum uri_normalizer_err uri_normalizer_path_merge_slashes(const struct ist path, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist newpath = *dst;
+
+ struct ist scanner = path;
+
+ /* The path will either be shortened or have the same length. */
+ if (size < istlen(path)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ while (istlen(scanner) > 0) {
+ const char current = istshift(&scanner);
+
+ if (current == '/') {
+ while (istlen(scanner) > 0 && *istptr(scanner) == '/')
+ scanner = istnext(scanner);
+ }
+
+ newpath = __istappend(newpath, current);
+ }
+
+ *dst = newpath;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/* Compares two query parameters by name. Query parameters are ordered
+ * as with memcmp. Shorter parameter names are ordered lower. Identical
+ * parameter names are compared by their pointer to maintain a stable
+ * sort.
+ */
+static int query_param_cmp(const void *a, const void *b)
+{
+ const struct ist param_a = *(struct ist*)a;
+ const struct ist param_b = *(struct ist*)b;
+ const struct ist param_a_name = iststop(param_a, '=');
+ const struct ist param_b_name = iststop(param_b, '=');
+
+ int cmp = istdiff(param_a_name, param_b_name);
+
+ if (cmp != 0)
+ return cmp;
+
+ /* The contents are identical: Compare the pointer. */
+ if (istptr(param_a) < istptr(param_b))
+ return -1;
+
+ if (istptr(param_a) > istptr(param_b))
+ return 1;
+
+ return 0;
+}
+
+/* Sorts the parameters within the given query string. */
+enum uri_normalizer_err uri_normalizer_query_sort(const struct ist query, const char delim, struct ist *dst)
+{
+ enum uri_normalizer_err err;
+
+ const size_t size = istclear(dst);
+ struct ist newquery = *dst;
+
+ struct ist scanner = query;
+
+ const struct buffer *trash = get_trash_chunk();
+ struct ist *params = (struct ist *)b_orig(trash);
+ const size_t max_param = b_size(trash) / sizeof(*params);
+ size_t param_count = 0;
+
+ size_t i;
+
+ /* The query will have the same length. */
+ if (size < istlen(query)) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ /* Handle the leading '?'. */
+ newquery = __istappend(newquery, istshift(&scanner));
+
+ while (istlen(scanner) > 0) {
+ const struct ist param = istsplit(&scanner, delim);
+
+ if (param_count + 1 > max_param) {
+ err = URI_NORMALIZER_ERR_ALLOC;
+ goto fail;
+ }
+
+ params[param_count] = param;
+ param_count++;
+ }
+
+ qsort(params, param_count, sizeof(*params), query_param_cmp);
+
+ for (i = 0; i < param_count; i++) {
+ if (i > 0)
+ newquery = __istappend(newquery, delim);
+
+ if (istcat(&newquery, params[i], size) < 0) {
+ /* This is impossible, because we checked the size of the destination buffer. */
+ my_unreachable();
+ err = URI_NORMALIZER_ERR_INTERNAL_ERROR;
+ goto fail;
+ }
+ }
+
+ *dst = newquery;
+
+ return URI_NORMALIZER_ERR_NONE;
+
+ fail:
+
+ return err;
+}
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ */