Fix misalignment issue during STUN data reading #233
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src/stun.c
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| @@ -908,7 +908,8 @@ int stun_read_attr(const void *data, size_t size, stun_message_t *msg, uint8_t * | |||
| JLOG_DEBUG("STUN ICE controlling attribute length invalid, length=%zu", length); | |||
| return -1; | |||
| } | |||
| msg->ice_controlling = ntohll(*((uint64_t *)attr->value)); | |||
| uint32_t* value32 = (uint32_t *)attr->value; | |||
| msg->ice_controlling = ntohll(((uint64_t)value32[1] << 32) | value32[0]); | |||
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There is actually an issue with endianess, as it reads the two 32-bit blocks reversed and expects ntohll to reverse them again. This works only if the architecture is little-endian.
In order to work on big endian architectures too, where ntoh* are no-ops, the conversion should be:
Suggested change
| msg->ice_controlling = ntohll(((uint64_t)value32[1] << 32) | value32[0]); | |
| msg->ice_controlling = ((uint64_t)ntohl(value32[0]) << 32) | ntohl(value32[1]); |
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Yeah my bad. I always get that wrong. I've committed the fix.
paullouisageneau
approved these changes
Jan 15, 2024
paullouisageneau
changed the title
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#232