dexter has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-msc/+/43237?usp=email )
Change subject: sgs_iface: clean up code in function decode_mme_name ......................................................................
sgs_iface: clean up code in function decode_mme_name
The function decode_mme_name is a bit hard to read and also has some minor problems we can optimize.
- do not call TLVP_LEN each time we need the length of the TLV IE. Call it once and keep the value in a variable - mme_name_enc holds the value part of the TLV IE, we can use this variable instead of calling TLVP_VAL all all the time. - When we have copied the value part of the TLV IE using memset, let's ensure that the string is terminated.
Related: OS#7058 Change-Id: I9aec8300f15264b68ac8e7805e93e621b12cafb2 --- M src/libmsc/sgs_iface.c 1 file changed, 5 insertions(+), 3 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-msc refs/changes/37/43237/1
diff --git a/src/libmsc/sgs_iface.c b/src/libmsc/sgs_iface.c index dd39816..aa0ccad 100644 --- a/src/libmsc/sgs_iface.c +++ b/src/libmsc/sgs_iface.c @@ -163,6 +163,7 @@ static int decode_mme_name(char *mme_name, size_t mme_name_len, const struct tlv_parsed *tp) { const uint8_t *mme_name_enc = TLVP_VAL_MINLEN(tp, SGSAP_IE_MME_NAME, SGS_MME_NAME_LEN); + size_t mme_name_enc_len = TLVP_LEN(tp, SGSAP_IE_MME_NAME); struct osmo_gummei gummei;
if (!mme_name_enc) @@ -170,17 +171,18 @@
/* do not accept over-long SGSAP_IE_MME_NAME IEs which would exceed the length * of the output buffer. */ - if (TLVP_LEN(tp, SGSAP_IE_MME_NAME) > mme_name_len - 1) + if (mme_name_enc_len > mme_name_len - 1) return -EINVAL;
/* some implementations use FDQN format violating TS 29.118 9.3.14 */ if (!osmo_parse_mme_domain(&gummei, (const char *) mme_name_enc)) { - memcpy(mme_name, mme_name_enc, TLVP_LEN(tp, SGSAP_IE_MME_NAME)); + memcpy(mme_name, mme_name_enc, mme_name_enc_len); + mme_name[mme_name_enc_len] = '\0'; return 0; }
/* decode the MME name from DNS labels to string */ - osmo_apn_to_str(mme_name, TLVP_VAL(tp, SGSAP_IE_MME_NAME), TLVP_LEN(tp, SGSAP_IE_MME_NAME)); + osmo_apn_to_str(mme_name, mme_name_enc, mme_name_enc_len);
/* try to parse the MME name into a GUMMEI as a test for the format */ if (osmo_parse_mme_domain(&gummei, mme_name) < 0)
-
dexter