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Fix [bug #51520] Big endian bug in apps/snmp/snmp_asn1.c

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Apply patch from Art Heers that does not need endianess checks
This commit is contained in:
Dirk Ziegelmeier 2017-07-26 09:28:07 +02:00
parent f5d7535323
commit aa4d978448
1 changed files with 5 additions and 31 deletions
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36
src/apps/snmp/snmp_asn1.c
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@ -579,51 +579,25 @@ snmp_asn1_dec_u64t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, u32_t *value
err_t err_t
snmp_asn1_dec_s32t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, s32_t *value) snmp_asn1_dec_s32t(struct snmp_pbuf_stream *pbuf_stream, u16_t len, s32_t *value)
{ {
#if BYTE_ORDER == LITTLE_ENDIAN
u8_t *lsb_ptr = (u8_t*)value;
#endif
#if BYTE_ORDER == BIG_ENDIAN
u8_t *lsb_ptr = (u8_t*)value + sizeof(s32_t) - 1;
#endif
u8_t sign;
u8_t data; u8_t data;
if ((len > 0) && (len < 5)) { if ((len > 0) && (len < 5)) {
PBUF_OP_EXEC(snmp_pbuf_stream_read(pbuf_stream, &data)); PBUF_OP_EXEC(snmp_pbuf_stream_read(pbuf_stream, &data));
len--;
if (data & 0x80) { if (data & 0x80) {
/* negative, start from -1 */ /* negative, start from -1 */
*value = -1; *value = (-1 << 8) | data;
sign = 1;
*lsb_ptr &= data;
} else { } else {
/* positive, start from 0 */ /* positive, start from 0 */
*value = 0; *value = data;
sign = 0;
*lsb_ptr |= data;
} }
len--;
/* OR/AND octets with value */ /* shift in the remaining value */
while (len > 0) { while (len > 0) {
PBUF_OP_EXEC(snmp_pbuf_stream_read(pbuf_stream, &data)); PBUF_OP_EXEC(snmp_pbuf_stream_read(pbuf_stream, &data));
*value = (*value << 8) | data;
len--; len--;
#if BYTE_ORDER == LITTLE_ENDIAN
*value <<= 8;
#endif
#if BYTE_ORDER == BIG_ENDIAN
*value >>= 8;
#endif
if (sign) {
*lsb_ptr |= 255;
*lsb_ptr &= data;
} else {
*lsb_ptr |= data;
}
} }
return ERR_OK; return ERR_OK;
} }