laforge has submitted this change. (
https://gerrit.osmocom.org/c/libosmocore/+/21535 )
Change subject: tlv: Introduce enum with error codes for TLV parser functions
......................................................................
tlv: Introduce enum with error codes for TLV parser functions
Change-Id: I0b352792089c5c0c714712d2ea237beb92e1d73f
---
M include/osmocom/gsm/tlv.h
M src/gsm/tlv_parser.c
2 files changed, 29 insertions(+), 17 deletions(-)
Approvals:
laforge: Looks good to me, approved
pespin: Looks good to me, but someone else must approve
Jenkins Builder: Verified
diff --git a/include/osmocom/gsm/tlv.h b/include/osmocom/gsm/tlv.h
index a307b3d..d34b7da 100644
--- a/include/osmocom/gsm/tlv.h
+++ b/include/osmocom/gsm/tlv.h
@@ -40,6 +40,16 @@
/*! maximum length of TLV of one byte length */
#define TVLV_MAX_ONEBYTE 0x7f
+/*! error return codes of various TLV parser functions */
+enum osmo_tlv_parser_error {
+ OSMO_TLVP_ERR_OFS_BEYOND_BUFFER = -1,
+ OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER = -2,
+ OSMO_TLVP_ERR_UNKNOWN_TLV_TYPE = -3,
+
+ OSMO_TLVP_ERR_MAND_IE_MISSING = -50,
+ OSMO_TLVP_ERR_IE_TOO_SHORT = -51,
+};
+
/*! gross length of a TVLV type field */
static inline uint16_t TVLV_GROSS_LEN(uint16_t len)
{
diff --git a/src/gsm/tlv_parser.c b/src/gsm/tlv_parser.c
index 24edd0c..7930d64 100644
--- a/src/gsm/tlv_parser.c
+++ b/src/gsm/tlv_parser.c
@@ -266,24 +266,24 @@
case TLV_TYPE_TLV:
tlv: /* GSM TS 04.07 11.2.4: Type 4 TLV */
if (buf + 1 > buf + buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
*o_val = buf+2;
*o_len = *(buf+1);
len = *o_len + 2;
if (len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
break;
case TLV_TYPE_vTvLV_GAN: /* 44.318 / 11.1.4 */
/* FIXME: variable-length TAG! */
if (*(buf+1) & 0x80) {
/* like TL16Vbut without highest bit of len */
if (2 > buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
*o_val = buf+3;
*o_len = (*(buf+1) & 0x7F) << 8 | *(buf+2);
len = *o_len + 3;
if (len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
} else {
/* like TLV */
goto tlv;
@@ -293,26 +293,26 @@
if (*(buf+1) & 0x80) {
/* like TLV, but without highest bit of len */
if (buf + 1 > buf + buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
*o_val = buf+2;
*o_len = *(buf+1) & 0x7f;
len = *o_len + 2;
if (len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
break;
}
/* like TL16V, fallthrough */
case TLV_TYPE_TL16V:
if (2 > buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
*o_val = buf+3;
*o_len = *(buf+1) << 8 | *(buf+2);
len = *o_len + 3;
if (len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
break;
default:
- return -3;
+ return OSMO_TLVP_ERR_UNKNOWN_TLV_TYPE;
}
return len;
@@ -370,12 +370,12 @@
const uint8_t *val;
uint16_t parsed_len;
if (ofs > buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
val = &buf[ofs+1];
len = buf[ofs];
parsed_len = len + 1;
if (ofs + parsed_len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
num_parsed++;
ofs += parsed_len;
/* store the resulting val and len */
@@ -391,12 +391,12 @@
const uint8_t *val;
uint16_t parsed_len;
if (ofs > buf_len)
- return -1;
+ return OSMO_TLVP_ERR_OFS_BEYOND_BUFFER;
val = &buf[ofs+1];
len = buf[ofs];
parsed_len = len + 1;
if (ofs + parsed_len > buf_len)
- return -2;
+ return OSMO_TLVP_ERR_OFS_LEN_BEYOND_BUFFER;
num_parsed++;
ofs += parsed_len;
/* store the resulting val and len */
@@ -667,7 +667,7 @@
const struct tlv_parsed *tp, int log_subsys,
const char *log_pfx)
{
const struct osmo_tlv_prot_msg_def *msg_def= &pdef->msg_def[msg_type];
- unsigned int num_err = 0;
+ unsigned int err = 0;
unsigned int i;
if (msg_def->mand_ies) {
@@ -677,7 +677,8 @@
LOGP(log_subsys, LOGL_ERROR, "%s %s %s: Missing
Mandatory IE: %s\n",
log_pfx, pdef->name,
osmo_tlv_prot_msg_name(pdef, msg_type),
osmo_tlv_prot_ie_name(pdef, iei));
- num_err++;
+ if (!err)
+ err = OSMO_TLVP_ERR_MAND_IE_MISSING;
}
}
}
@@ -693,11 +694,12 @@
LOGP(log_subsys, LOGL_ERROR, "%s %s %s: Short IE %s: %u
< %u\n", log_pfx,
pdef->name, osmo_tlv_prot_msg_name(pdef, msg_type),
osmo_tlv_prot_ie_name(pdef, i), TLVP_LEN(tp, i),
min_len);
- num_err++;
+ if (!err)
+ err = OSMO_TLVP_ERR_IE_TOO_SHORT;
}
}
- return -num_err;
+ return err;
}
/*! Parse + Validate a TLV-encoded message against the protocol definition.
--
To view, visit https://gerrit.osmocom.org/c/libosmocore/+/21535
To unsubscribe, or for help writing mail filters, visit
https://gerrit.osmocom.org/settings
Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-Change-Id: I0b352792089c5c0c714712d2ea237beb92e1d73f
Gerrit-Change-Number: 21535
Gerrit-PatchSet: 10
Gerrit-Owner: laforge <[email protected]>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: laforge <[email protected]>
Gerrit-Reviewer: pespin <[email protected]>
Gerrit-MessageType: merged
