summaryrefslogtreecommitdiff
path: root/utils/http/strict-transport-security.c
diff options
context:
space:
mode:
Diffstat (limited to 'utils/http/strict-transport-security.c')
-rw-r--r--utils/http/strict-transport-security.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/utils/http/strict-transport-security.c b/utils/http/strict-transport-security.c
new file mode 100644
index 000000000..9de610c73
--- /dev/null
+++ b/utils/http/strict-transport-security.c
@@ -0,0 +1,341 @@
+/*
+ * Copyright 2018 John-Mark Bell <jmb@netsurf-browser.org>
+ *
+ * This file is part of NetSurf, http://www.netsurf-browser.org/
+ *
+ * NetSurf 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; version 2 of the License.
+ *
+ * NetSurf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <limits.h>
+#include <stdlib.h>
+
+#include "utils/corestrings.h"
+#include "utils/http.h"
+
+#include "utils/http/generics.h"
+#include "utils/http/primitives.h"
+
+/**
+ * Representation of a Strict-Transport-Security
+ */
+struct http_strict_transport_security {
+ uint32_t max_age; /**< Max age (delta seconds) */
+ bool include_sub_domains; /**< Whether subdomains are included */
+};
+
+/**
+ * Representation of a directive
+ */
+typedef struct http_directive {
+ http__item base;
+
+ lwc_string *name; /**< Parameter name */
+ lwc_string *value; /**< Parameter value (optional) */
+} http_directive;
+
+
+static void http_destroy_directive(http_directive *self)
+{
+ lwc_string_unref(self->name);
+ if (self->value != NULL) {
+ lwc_string_unref(self->value);
+ }
+ free(self);
+}
+
+static nserror http__parse_directive(const char **input,
+ http_directive **result)
+{
+ const char *pos = *input;
+ lwc_string *name;
+ lwc_string *value = NULL;
+ http_directive *directive;
+ nserror error;
+
+ /* token [ "=" ( token | quoted-string ) ] */
+
+ error = http__parse_token(&pos, &name);
+ if (error != NSERROR_OK)
+ return error;
+
+ http__skip_LWS(&pos);
+
+ if (*pos == '=') {
+ pos++;
+
+ http__skip_LWS(&pos);
+
+ if (*pos == '"')
+ error = http__parse_quoted_string(&pos, &value);
+ else
+ error = http__parse_token(&pos, &value);
+
+ if (error != NSERROR_OK) {
+ lwc_string_unref(name);
+ return error;
+ }
+ }
+
+ directive = malloc(sizeof(*directive));
+ if (directive == NULL) {
+ if (value != NULL) {
+ lwc_string_unref(value);
+ }
+ lwc_string_unref(name);
+ return NSERROR_NOMEM;
+ }
+
+ HTTP__ITEM_INIT(directive, NULL, http_destroy_directive);
+ directive->name = name;
+ directive->value = value;
+
+ *result = directive;
+ *input = pos;
+
+ return NSERROR_OK;
+}
+
+static void http_directive_list_destroy(http_directive *list)
+{
+ http__item_list_destroy(list);
+}
+
+static nserror http_directive_list_find_item(const http_directive *list,
+ lwc_string *name, lwc_string **value)
+{
+ bool match;
+
+ while (list != NULL) {
+ if (lwc_string_caseless_isequal(name, list->name,
+ &match) == lwc_error_ok && match)
+ break;
+
+ list = (http_directive *) list->base.next;
+ }
+
+ if (list == NULL)
+ return NSERROR_NOT_FOUND;
+
+ if (list->value != NULL) {
+ *value = lwc_string_ref(list->value);
+ } else {
+ *value = NULL;
+ }
+
+ return NSERROR_OK;
+}
+
+static const http_directive *http_directive_list_iterate(
+ const http_directive *cur,
+ lwc_string **name, lwc_string **value)
+{
+ if (cur == NULL)
+ return NULL;
+
+ *name = lwc_string_ref(cur->name);
+ if (cur->value != NULL) {
+ *value = lwc_string_ref(cur->value);
+ } else {
+ *value = NULL;
+ }
+
+ return (http_directive *) cur->base.next;
+}
+
+static uint32_t count(const http_directive *list, lwc_string *key)
+{
+ uint32_t count = 0;
+ bool match;
+
+ while (list != NULL) {
+ if (lwc_string_caseless_isequal(key, list->name,
+ &match) == lwc_error_ok && match) {
+ count++;
+ }
+
+ list = (http_directive *) list->base.next;
+ }
+
+ return count;
+}
+
+static bool check_duplicates(const http_directive *directives)
+{
+ bool result = true;
+ const http_directive *key = directives;
+
+ if (key == NULL) {
+ /* No directives, so there can't be any duplicates */
+ return true;
+ }
+
+ do {
+ lwc_string *name = NULL, *value = NULL;
+
+ key = http_directive_list_iterate(key, &name, &value);
+
+ result &= (count(directives, name) == 1);
+
+ lwc_string_unref(name);
+ if (value != NULL) {
+ lwc_string_unref(value);
+ }
+ } while (key != NULL);
+
+ return result;
+}
+
+static nserror parse_max_age(lwc_string *value, uint32_t *result)
+{
+ const char *pos = lwc_string_data(value);
+ const char *end = pos + lwc_string_length(value);
+ uint32_t val = 0;
+
+ /* 1*DIGIT */
+
+ if (pos == end) {
+ /* Blank value */
+ return NSERROR_NOT_FOUND;
+ }
+
+ while (pos < end) {
+ if ('0' <= *pos && *pos <= '9') {
+ uint32_t nv = val * 10 + (*pos - '0');
+ if (nv < val) {
+ val = UINT_MAX;
+ } else {
+ val = nv;
+ }
+ } else {
+ /* Non-digit */
+ return NSERROR_NOT_FOUND;
+ }
+
+ pos++;
+ }
+
+ *result = val;
+
+ return NSERROR_OK;
+}
+
+/* See strict-transport-security.h for documentation */
+nserror http_parse_strict_transport_security(const char *header_value,
+ http_strict_transport_security **result)
+{
+ const char *pos = header_value;
+ http_strict_transport_security *sts;
+ http_directive *first = NULL;
+ http_directive *directives = NULL;
+ lwc_string *max_age_str = NULL, *isd_str = NULL;
+ uint32_t max_age;
+ bool include_sub_domains = false;
+ nserror error;
+
+ /* directive *( ";" directive ) */
+
+ http__skip_LWS(&pos);
+
+ error = http__parse_directive(&pos, &first);
+ if (error != NSERROR_OK) {
+ return error;
+ }
+
+ http__skip_LWS(&pos);
+
+ if (*pos == ';') {
+ error = http__item_list_parse(&pos,
+ http__parse_directive, first, &directives);
+ if (error != NSERROR_OK) {
+ if (directives != NULL) {
+ http_directive_list_destroy(directives);
+ }
+ return error;
+ }
+ } else {
+ directives = first;
+ }
+
+ /* Each directive must only appear once */
+ if (check_duplicates(directives) == false) {
+ http_directive_list_destroy(directives);
+ return NSERROR_NOT_FOUND;
+ }
+
+ /* max-age is required */
+ error = http_directive_list_find_item(directives,
+ corestring_lwc_max_age, &max_age_str);
+ if (error != NSERROR_OK || max_age_str == NULL) {
+ http_directive_list_destroy(directives);
+ return NSERROR_NOT_FOUND;
+ }
+
+ error = parse_max_age(max_age_str, &max_age);
+ if (error != NSERROR_OK) {
+ lwc_string_unref(max_age_str);
+ http_directive_list_destroy(directives);
+ return NSERROR_NOT_FOUND;
+ }
+ lwc_string_unref(max_age_str);
+
+ /* includeSubDomains is optional and valueless */
+ error = http_directive_list_find_item(directives,
+ corestring_lwc_includesubdomains, &isd_str);
+ if (error != NSERROR_OK && error != NSERROR_NOT_FOUND) {
+ http_directive_list_destroy(directives);
+ return NSERROR_NOT_FOUND;
+ } else if (error == NSERROR_OK) {
+ if (isd_str != NULL) {
+ /* Present, but not valueless: invalid */
+ lwc_string_unref(isd_str);
+ http_directive_list_destroy(directives);
+ return NSERROR_NOT_FOUND;
+ }
+ include_sub_domains = true;
+ }
+ http_directive_list_destroy(directives);
+
+ sts = malloc(sizeof(*sts));
+ if (sts == NULL) {
+ return NSERROR_NOMEM;
+ }
+
+ sts->max_age = max_age;
+ sts->include_sub_domains = include_sub_domains;
+
+ *result = sts;
+
+ return NSERROR_OK;
+}
+
+/* See strict-transport-security.h for documentation */
+void http_strict_transport_security_destroy(
+ http_strict_transport_security *victim)
+{
+ free(victim);
+}
+
+/* See strict-transport-security.h for documentation */
+uint32_t http_strict_transport_security_max_age(
+ http_strict_transport_security *sts)
+{
+ return sts->max_age;
+}
+
+/* See strict-transport-security.h for documentation */
+bool http_strict_transport_security_include_subdomains(
+ http_strict_transport_security *sts)
+{
+ return sts->include_sub_domains;
+}
+