From 146bc77c98ace3d1cc672986669650d2e1da71f3 Mon Sep 17 00:00:00 2001 From: Daniel Danzberger Date: Tue, 10 May 2022 13:34:03 +0200 Subject: [PATCH] umbim: fix invalid mbim message string encoding Strings in mbim messages have to follow these formatting rules: - 4 byte alignment, padded if not. - utf-16 little endian. Fixes: - mbim connect fails with more than 1 string parameter (apn/user/pass) when they are not 4 byte aligned. Signed-off-by: Daniel Danzberger --- mbim-msg.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/mbim-msg.c b/mbim-msg.c index 5ec04f4..8f21aa9 100644 --- a/mbim-msg.c +++ b/mbim-msg.c @@ -53,8 +53,10 @@ mbim_add_payload(uint8_t len) int mbim_encode_string(struct mbim_string *str, char *in) { - int l = strlen(in); - int s = mbim_add_payload(l * 2); + const int l = strlen(in); + const int utf16_len = l * 2; + const int pad_len = utf16_len % 4; + const int s = mbim_add_payload(utf16_len + pad_len); uint8_t *p = &payload_buffer[s]; int i; @@ -62,14 +64,14 @@ mbim_encode_string(struct mbim_string *str, char *in) return -1; str->offset = htole32(s); - str->length = htole32(l * 2); + str->length = htole32(utf16_len); + for (i = 0; i < l; i++) p[i * 2] = in[i]; return 0; } - char * mbim_get_string(struct mbim_string *str, char *in) { -- 2.30.2