Handle %xx encoding in querystring

Convert valid %xx expressions in querystring to ascii, ignore invalid
expressions (i.e. eat the three characters %xx).

Signed-off-by: Lars Hjemli <larsh@hal-2004.(none)>

3 files changed, 36 insertions, 0 deletions

diff --git a/cgit.h b/cgit.h
index 249650e..eb8f08c 100644
--- a/cgit.h
+++ b/cgit.h
@@ -62,16 +62,18 @@ extern char *cgit_query_sha2;
 extern int   cgit_query_ofs;
 
 extern int htmlfd;
 
 extern void cgit_global_config_cb(const char *name, const char *value);
 extern void cgit_repo_config_cb(const char *name, const char *value);
 extern void cgit_querystring_cb(const char *name, const char *value);
 
+extern int hextoint(char c);
+
 extern void *cgit_free_commitinfo(struct commitinfo *info);
 
 extern char *fmt(const char *format,...);
 
 extern void html(const char *txt);
 extern void htmlf(const char *format,...);
 extern void html_txt(char *txt);
 extern void html_ntxt(int len, char *txt);
diff --git a/parsing.c b/parsing.c
index 1b22fcf..4173dd4 100644
--- a/parsing.c
+++ b/parsing.c
@@ -74,31 +74,52 @@ int cgit_read_config(const char *filename, configfn fn)
 
 	while((len = read_config_line(f, line, &value, sizeof(line))) > 0)
 		(*fn)(line, value);
 
 	fclose(f);
 	return ret;
 }
 
+char *convert_query_hexchar(char *txt)
+{
+	int d1, d2;
+	if (strlen(txt) < 3) {
+		*txt = '\0';
+		return txt-1;
+	}
+	d1 = hextoint(*(txt+1));
+	d2 = hextoint(*(txt+2));
+	if (d1<0 || d2<0) {
+		strcpy(txt, txt+3);
+		return txt-1;
+	} else {
+		*txt = d1 * 16 + d2;
+		strcpy(txt+1, txt+3);
+		return txt;
+	}
+}
+
 int cgit_parse_query(char *txt, configfn fn)
 {
 	char *t, *value = NULL, c;
 
 	if (!txt)
 		return 0;
 
 	t = txt = xstrdup(txt);
  
 	while((c=*t) != '\0') {
 		if (c=='=') {
 			*t = '\0';
 			value = t+1;
 		} else if (c=='+') {
 			*t = ' ';
+		} else if (c=='%') {
+			t = convert_query_hexchar(t);
 		} else if (c=='&') {
 			*t = '\0';
 			(*fn)(txt, value);
 			txt = t+1;
 			value = NULL;
 		}
 		t++;
 	}
diff --git a/shared.c b/shared.c
index 7def51a..e4595fa 100644
--- a/shared.c
+++ b/shared.c
@@ -108,8 +108,21 @@ void *cgit_free_commitinfo(struct commitinfo *info)
 	free(info->author);
 	free(info->author_email);
 	free(info->committer);
 	free(info->committer_email);
 	free(info->subject);
 	free(info);
 	return NULL;
 }
+
+int hextoint(char c)
+{
+	if (c >= 'a' && c <= 'f')
+		return 10 + c - 'a';
+	else if (c >= 'A' && c <= 'F')
+		return 10 + c - 'A';
+	else if (c >= '0' && c <= '9')
+		return c - '0';
+	else
+		return -1;
+}
+