[PATCH] osmocom-bb[master]: mobile/gsm480_ss.c: use secure gsm_7bit_(en|de)code_n_ussd

[Vadim Yanitskiy]

Review at  https://gerrit.osmocom.org/4641

mobile/gsm480_ss.c: use secure gsm_7bit_(en|de)code_n_ussd

Since some 'gsm_7bit_*' functions were deprecated and replaced by
more secure ones with the '_n_' suffix in names, it's better to
use the updated functions.

Change-Id: If8a1983592f5800e3981f29962eb333ac9473f40
---
M src/host/layer23/src/mobile/gsm480_ss.c
1 file changed, 14 insertions(+), 24 deletions(-)


  git pull ssh://gerrit.osmocom.org:29418/osmocom-bb refs/changes/41/4641/1

diff --git a/src/host/layer23/src/mobile/gsm480_ss.c b/src/host/layer23/src/mobile/gsm480_ss.c
index 8d025e9..6f06cf7 100644
--- a/src/host/layer23/src/mobile/gsm480_ss.c
+++ b/src/host/layer23/src/mobile/gsm480_ss.c
@@ -193,20 +193,23 @@
 	{ 0, NULL }
 };
 
-static int gsm480_ss_result(struct osmocom_ms *ms, const char *response,
+static int gsm480_ss_result(struct osmocom_ms *ms, char *response,
 	uint8_t error)
 {
 	vty_notify(ms, NULL);
 	if (response) {
-		char text[256], *t = text, *s;
+		char *line;
+		int i;
 
-		strncpy(text, response, sizeof(text) - 1);
-		text[sizeof(text) - 1] = '\0';
-		while ((s = strchr(text, '\r')))
-			*s = '\n';
-		while ((s = strsep(&t, "\n"))) {
-			vty_notify(ms, "Service response: %s\n", s);
-		}
+		for (i = 0; response[i]; i++)
+			if (response[i] == '\r')
+				response[i] = '\n';
+
+		if (response[0] && response[strlen(response) - 1] == '\n')
+			response[strlen(response) - 1] = '\0';
+
+		while ((line = strsep(&response, "\n")))
+			vty_notify(ms, "Service response: %s\n", line);
 	} else if (error)
 		vty_notify(ms, "Service request failed: %s\n",
 			get_value_string(gsm480_err_names, error));
@@ -532,7 +535,7 @@
 	}
 
 	/* Encode service request */
-	length = gsm_7bit_encode(msg->data, text);
+	gsm_7bit_encode_n_ussd(msg->data, msgb_tailroom(msg), text, &length);
 	msgb_put(msg, length);
 
 	/* Then wrap it as an Octet String */
@@ -730,7 +733,6 @@
 {
 	int num_chars;
 	char text[256];
-	int i;
 	const uint8_t *tag_data;
 	int tag_len;
 
@@ -772,19 +774,7 @@
 		return -EINVAL;
 	}
 	num_chars = tag_len * 8 / 7;
-	/* Prevent a mobile-originated buffer-overrun! */
-	if (num_chars > sizeof(text) - 1)
-		num_chars = sizeof(text) - 1;
-	text[sizeof(text) - 1] = '\0';
-	gsm_7bit_decode(text, tag_data, num_chars);
-
-	for (i = 0; text[i]; i++) {
-		if (text[i] == '\r')
-			text[i] = '\n';
-	}
-	/* remove last CR, if exists */
-	if (text[0] && text[strlen(text) - 1] == '\n')
-		text[strlen(text) - 1] = '\0';
+	gsm_7bit_decode_n_ussd(text, sizeof(text), tag_data, num_chars);
 	gsm480_ss_result(trans->ms, text, 0);
 
 	return 0;

-- 
To view, visit https://gerrit.osmocom.org/4641
To unsubscribe, visit https://gerrit.osmocom.org/settings

Gerrit-MessageType: newchange
Gerrit-Change-Id: If8a1983592f5800e3981f29962eb333ac9473f40
Gerrit-PatchSet: 1
Gerrit-Project: osmocom-bb
Gerrit-Branch: master
Gerrit-Owner: Vadim Yanitskiy <axilirator at gmail.com>