commit 05d1951: [Minor] Implement backslashes replacement while we normalise http paths

[Vsevolod Stakhov]

Author: Vsevolod Stakhov
Date: 2021-07-30 11:25:40 +0100
URL: https://github.com/rspamd/rspamd/commit/05d1951b5cfb9b72378eb3c1bdfdaa025b355789 (HEAD -> master)

[Minor] Implement backslashes replacement while we normalise http paths

---
 src/libserver/http/http_util.c | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/libserver/http/http_util.c b/src/libserver/http/http_util.c
index fd5adb3c1..e6ba314d0 100644
--- a/src/libserver/http/http_util.c
+++ b/src/libserver/http/http_util.c
@@ -312,7 +312,8 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 		st_got_dot_dot,
 		st_got_slash,
 		st_got_slash_slash,
-	} state = st_normal;
+		st_replace_backslash,
+	} state = st_normal, next_state;
 
 	p = path;
 	end = path + len;
@@ -329,6 +330,11 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 				state = st_got_dot;
 				dot = p;
 			}
+			else if (G_UNLIKELY (*p == '\\')) {
+				state = st_replace_backslash;
+				next_state = st_normal;
+				continue;
+			}
 			else {
 				*o++ = *p;
 			}
@@ -340,6 +346,11 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 				*o++ = *p;
 				state = st_got_slash_slash;
 			}
+			else if (G_UNLIKELY (*p == '\\')) {
+				state = st_replace_backslash;
+				next_state = st_got_slash;
+				continue;
+			}
 			else if (G_UNLIKELY (*p == '.')) {
 				dot = p;
 				state = st_got_dot;
@@ -375,6 +386,11 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 				/* Ignore last slash */
 				state = st_normal;
 			}
+			else if (G_UNLIKELY (*p == '\\')) {
+				state = st_replace_backslash;
+				next_state = st_got_dot;
+				continue;
+			}
 			else if (*p == '.') {
 				/* Double dot character */
 				state = st_got_dot_dot;
@@ -436,6 +452,11 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 					continue;
 				}
 			}
+			else if (G_UNLIKELY (*p == '\\')) {
+				state = st_replace_backslash;
+				next_state = st_got_dot_dot;
+				continue;
+			}
 			else {
 				/* We have something like ..bla or ... */
 				if (slash) {
@@ -455,6 +476,14 @@ rspamd_http_normalize_path_inplace (gchar *path, guint len, gsize *nlen)
 
 			p ++;
 			break;
+		case st_replace_backslash:
+			/*
+			 * Replace backslash and return to the previous state as it was
+			 * a normal slash
+			 */
+			*(gchar *)p = '/';
+			state = next_state;
+			break;
 		}
 	}