From 5aaffb68aefcb56abb2cb3086bd3555a00efdae4 Mon Sep 17 00:00:00 2001
From: Maximilian Fridrich <m.fridrich@commend.com>
Date: Tue, 2 May 2023 10:00:34 +0200
Subject: [PATCH] uric/contact: fix display name and contact header uri
 escaping (#762)

* uric: fix display name uri escaping

In display names, LWS may not be escaped according to RFC 3261 section
25.1.

* contact: escape Contact header SIP URI

* uri,contact: improve uri escaping of user part

* dialog: do not escape display name in FROM header

The display name is sent as a quoted-string which must not be escaped.
Further, basically all UTF-8 characters are allowed in display names,
so not checking it should be fine for almost all cases.

* uric: remove unused functions
---
 include/re_uri.h  |  1 +
 src/sip/contact.c | 12 ++++++++----
 src/sip/dialog.c  |  4 +---
 src/uri/uri.c     | 16 ++++++++++++++++
 src/uri/uric.c    | 40 ----------------------------------------
 5 files changed, 26 insertions(+), 47 deletions(-)

diff --git a/include/re_uri.h b/include/re_uri.h
index 2843b69e6..c8436bf9d 100644
--- a/include/re_uri.h
+++ b/include/re_uri.h
@@ -44,6 +44,7 @@ int uri_param_unescape(struct re_printf *pf, const struct pl *pl);
 int uri_header_escape(struct re_printf *pf, const struct pl *pl);
 int uri_header_unescape(struct re_printf *pf, const struct pl *pl);
 int uri_display_name_escape(struct re_printf *pf, const struct pl *pl);
+int uri_escape_user(struct re_printf *pf, const char *user);
 int uri_escape(struct re_printf *pf, const char *uri);
 int uri_escape_pl(struct re_printf *pf, const struct pl *pl);
 int uri_unescape_pl(struct re_printf *pf, const struct pl *pl);
diff --git a/src/sip/contact.c b/src/sip/contact.c
index 670338428..6cb89b08e 100644
--- a/src/sip/contact.c
+++ b/src/sip/contact.c
@@ -47,11 +47,15 @@ int sip_contact_print(struct re_printf *pf, const struct sip_contact *contact)
 	if (!contact)
 		return 0;
 
-	if (contact->uri && strchr(contact->uri, ':'))
-		return re_hprintf(pf, "Contact: <%s>\r\n", contact->uri);
-	else
-		return re_hprintf(pf, "Contact: <sip:%s@%J%s>\r\n",
+	if (contact->uri && strchr(contact->uri, ':')) {
+		return re_hprintf(pf, "Contact: <%H>\r\n", uri_escape,
+				  contact->uri);
+	}
+	else {
+		return re_hprintf(pf, "Contact: <sip:%H@%J%s>\r\n",
+				  uri_escape_user,
 				  contact->uri,
 				  contact->addr,
 				  sip_transp_param(contact->tp));
+	}
 }
diff --git a/src/sip/dialog.c b/src/sip/dialog.c
index ebf009e91..89a9376d1 100644
--- a/src/sip/dialog.c
+++ b/src/sip/dialog.c
@@ -122,9 +122,7 @@ int sip_dialog_alloc(struct sip_dialog **dlgp,
 	dlg->cpos = dlg->mb->pos;
 	err |= mbuf_printf(dlg->mb, "From: ");
 	if (from_name) {
-		pl_set_str(&pl, from_name);
-		err |= mbuf_printf(dlg->mb, "\"%H\" ", uri_display_name_escape,
-				   &pl);
+		err |= mbuf_printf(dlg->mb, "\"%s\" ", from_name);
 	}
 	err |= mbuf_printf(dlg->mb, "<%H>", uri_escape, from_uri);
 	err |= mbuf_printf(dlg->mb, ";tag=%016llx\r\n", ltag);
diff --git a/src/uri/uri.c b/src/uri/uri.c
index 6d9375ad4..3858081fe 100644
--- a/src/uri/uri.c
+++ b/src/uri/uri.c
@@ -271,6 +271,22 @@ int uri_headers_apply(const struct pl *pl, uri_apply_h *ah, void *arg)
 }
 
 
+/**
+ * Escape user part of SIP URI
+ *
+ * @param pf   Print function to encode into
+ * @param user User part of SIP URI
+ *
+ * @return 0 if success, otherwise errorcode
+ */
+int uri_escape_user(struct re_printf *pf, const char *user)
+{
+	struct pl pl;
+	pl_set_str(&pl, user);
+	return uri_user_escape(pf, &pl);
+}
+
+
 static int uri_escape_helper(struct re_printf *pf, const struct pl *pl,
 			     bool unescape)
 {
diff --git a/src/uri/uric.c b/src/uri/uric.c
index f59e0849a..bb9545ee5 100644
--- a/src/uri/uric.c
+++ b/src/uri/uric.c
@@ -120,33 +120,6 @@ static bool is_param_unreserved(char c)
 }
 
 
-static bool is_token_non_alphanum(int c)
-{
-	switch (c) {
-
-	case '-':
-	case '.':
-	case '!':
-	case '%':
-	case '*':
-	case '_':
-	case '+':
-	case '`':
-	case '\'':
-	case '~':
-		return true;
-	default:
-		return false;
-	}
-}
-
-
-static bool is_token(char c)
-{
-	return isalnum((unsigned char)c) || is_token_non_alphanum(c);
-}
-
-
 static bool is_paramchar(char c)
 {
 	return is_param_unreserved(c) || is_unreserved(c);
@@ -332,16 +305,3 @@ int uri_header_unescape(struct re_printf *pf, const struct pl *pl)
 	return comp_unescape(pf, pl, is_hvalue);
 }
 
-
-/**
- * Escape display name
- *
- * @param pf Print function
- * @param pl String to escape
- *
- * @return 0 if success, otherwise errorcode
- */
-int uri_display_name_escape(struct re_printf *pf, const struct pl *pl)
-{
-	return comp_escape(pf, pl, is_token);
-}