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Diffstat (limited to 'modules/filters/mod_substitute.c')
-rw-r--r--modules/filters/mod_substitute.c86
1 files changed, 72 insertions, 14 deletions
diff --git a/modules/filters/mod_substitute.c b/modules/filters/mod_substitute.c
index 15cd8ee4..9326348c 100644
--- a/modules/filters/mod_substitute.c
+++ b/modules/filters/mod_substitute.c
@@ -33,6 +33,13 @@
#define APR_WANT_STRFUNC
#include "apr_want.h"
+/*
+ * We want to limit the memory usage in a way that is predictable.
+ * Therefore we limit the resulting length of the line.
+ * This is the default value.
+ */
+#define AP_SUBST_MAX_LINE_LENGTH (1024*1024)
+
static const char substitute_filter_name[] = "SUBSTITUTE";
module AP_MODULE_DECLARE_DATA substitute_module;
@@ -48,6 +55,8 @@ typedef struct subst_pattern_t {
typedef struct {
apr_array_header_t *patterns;
+ apr_size_t max_line_length;
+ int max_line_length_set;
} subst_dir_conf;
typedef struct {
@@ -64,6 +73,7 @@ static void *create_substitute_dcfg(apr_pool_t *p, char *d)
(subst_dir_conf *) apr_pcalloc(p, sizeof(subst_dir_conf));
dcfg->patterns = apr_array_make(p, 10, sizeof(subst_pattern_t));
+ dcfg->max_line_length = AP_SUBST_MAX_LINE_LENGTH;
return dcfg;
}
@@ -76,15 +86,14 @@ static void *merge_substitute_dcfg(apr_pool_t *p, void *basev, void *overv)
a->patterns = apr_array_append(p, over->patterns,
base->patterns);
+ a->max_line_length = over->max_line_length_set ?
+ over->max_line_length : base->max_line_length;
+ a->max_line_length_set = over->max_line_length_set ?
+ over->max_line_length_set : base->max_line_length_set;
return a;
}
#define AP_MAX_BUCKETS 1000
-/*
- * We want to limit the memory usage in a way that is predictable. Therefore
- * we limit the resulting length of the line to this value.
- */
-#define AP_SUBST_MAX_LINE_LENGTH (128*MAX_STRING_LEN)
#define SEDRMPATBCKT(b, offset, tmp_b, patlen) do { \
apr_bucket_split(b, offset); \
@@ -143,9 +152,9 @@ static apr_status_t do_pattmatch(ap_filter_t *f, apr_bucket *inb,
const char *repl;
/*
* space_left counts how many bytes we have left until the
- * line length reaches AP_SUBST_MAX_LINE_LENGTH.
+ * line length reaches max_line_length.
*/
- apr_size_t space_left = AP_SUBST_MAX_LINE_LENGTH;
+ apr_size_t space_left = cfg->max_line_length;
apr_size_t repl_len = strlen(script->replacement);
while ((repl = apr_strmatch(script->pattern, buff, bytes)))
{
@@ -161,7 +170,7 @@ static apr_status_t do_pattmatch(ap_filter_t *f, apr_bucket *inb,
* are constanting allocing space and copying
* strings.
*/
- if (vb.strlen + len + repl_len > AP_SUBST_MAX_LINE_LENGTH)
+ if (vb.strlen + len + repl_len > cfg->max_line_length)
return APR_ENOMEM;
ap_varbuf_strmemcat(&vb, buff, len);
ap_varbuf_strmemcat(&vb, script->replacement, repl_len);
@@ -228,19 +237,25 @@ static apr_status_t do_pattmatch(ap_filter_t *f, apr_bucket *inb,
int left = bytes;
const char *pos = buff;
char *repl;
- apr_size_t space_left = AP_SUBST_MAX_LINE_LENGTH;
+ apr_size_t space_left = cfg->max_line_length;
while (!ap_regexec_len(script->regexp, pos, left,
AP_MAX_REG_MATCH, regm, 0)) {
apr_status_t rv;
have_match = 1;
if (script->flatten && !force_quick) {
+ /* check remaining buffer size */
+ /* Note that the last param in ap_varbuf_regsub below
+ * must stay positive. If it gets 0, it would mean
+ * unlimited space available. */
+ if (vb.strlen + regm[0].rm_so >= cfg->max_line_length)
+ return APR_ENOMEM;
/* copy bytes before the match */
if (regm[0].rm_so > 0)
ap_varbuf_strmemcat(&vb, pos, regm[0].rm_so);
- /* add replacement string */
+ /* add replacement string, last argument is unsigned! */
rv = ap_varbuf_regsub(&vb, script->replacement, pos,
AP_MAX_REG_MATCH, regm,
- AP_SUBST_MAX_LINE_LENGTH - vb.strlen);
+ cfg->max_line_length - vb.strlen);
if (rv != APR_SUCCESS)
return rv;
}
@@ -309,6 +324,9 @@ static apr_status_t substitute_filter(ap_filter_t *f, apr_bucket_brigade *bb)
apr_bucket *tmp_b;
apr_bucket_brigade *tmp_bb = NULL;
apr_status_t rv;
+ subst_dir_conf *cfg =
+ (subst_dir_conf *) ap_get_module_config(f->r->per_dir_config,
+ &substitute_module);
substitute_module_ctx *ctx = f->ctx;
@@ -381,7 +399,7 @@ static apr_status_t substitute_filter(ap_filter_t *f, apr_bucket_brigade *bb)
&fbytes, ctx->tpool);
if (rv != APR_SUCCESS)
goto err;
- if (fbytes > AP_SUBST_MAX_LINE_LENGTH) {
+ if (fbytes > cfg->max_line_length) {
rv = APR_ENOMEM;
goto err;
}
@@ -447,7 +465,7 @@ static apr_status_t substitute_filter(ap_filter_t *f, apr_bucket_brigade *bb)
&fbytes, ctx->tpool);
if (rv != APR_SUCCESS)
goto err;
- if (fbytes > AP_SUBST_MAX_LINE_LENGTH) {
+ if (fbytes > cfg->max_line_length) {
/* Avoid pflattening further lines, we will
* abort later on anyway.
*/
@@ -627,6 +645,44 @@ static const char *set_pattern(cmd_parms *cmd, void *cfg, const char *line)
return NULL;
}
+#define KBYTE 1024
+#define MBYTE 1048576
+#define GBYTE 1073741824
+
+static const char *set_max_line_length(cmd_parms *cmd, void *cfg, const char *arg)
+{
+ subst_dir_conf *dcfg = (subst_dir_conf *)cfg;
+ apr_off_t max;
+ char *end;
+ apr_status_t rv;
+
+ rv = apr_strtoff(&max, arg, &end, 10);
+ if (rv == APR_SUCCESS) {
+ if ((*end == 'K' || *end == 'k') && !end[1]) {
+ max *= KBYTE;
+ }
+ else if ((*end == 'M' || *end == 'm') && !end[1]) {
+ max *= MBYTE;
+ }
+ else if ((*end == 'G' || *end == 'g') && !end[1]) {
+ max *= GBYTE;
+ }
+ else if (*end && /* neither empty nor [Bb] */
+ ((*end != 'B' && *end != 'b') || end[1])) {
+ rv = APR_EGENERAL;
+ }
+ }
+
+ if (rv != APR_SUCCESS || max < 0)
+ {
+ return "SubstituteMaxLineLength must be a non-negative integer optionally "
+ "suffixed with 'b', 'k', 'm' or 'g'.";
+ }
+ dcfg->max_line_length = (apr_size_t)max;
+ dcfg->max_line_length_set = 1;
+ return NULL;
+}
+
#define PROTO_FLAGS AP_FILTER_PROTO_CHANGE|AP_FILTER_PROTO_CHANGE_LENGTH
static void register_hooks(apr_pool_t *pool)
{
@@ -635,8 +691,10 @@ static void register_hooks(apr_pool_t *pool)
}
static const command_rec substitute_cmds[] = {
- AP_INIT_TAKE1("Substitute", set_pattern, NULL, OR_ALL,
+ AP_INIT_TAKE1("Substitute", set_pattern, NULL, OR_FILEINFO,
"Pattern to filter the response content (s/foo/bar/[inf])"),
+ AP_INIT_TAKE1("SubstituteMaxLineLength", set_max_line_length, NULL, OR_FILEINFO,
+ "Maximum line length"),
{NULL}
};
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-06 19:00:01 +0000