mgmt: hawkbit: domain name buffer length and add check #89497
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also after line 287 in hawkbit.c
so that the length is not checkt that strict of the server_addr:
line 288: if (len > sizeof(hb_cfg.server_addr)) {
line 292: rc = read_cb(cb_arg, &hb_cfg.server_addr, len);
line 361: (void)cb("hawkbit/server_addr", &hb_cfg.server_addr, strlen(hb_cfg.server_addr));
The hawkbit subsystem was erroneously using DNS_MAX_NAME_SIZE as the maximum query length. This limited query strings to only 20 bytes, truncating many domain names. Signed-off-by: Neal Jackson <[email protected]>
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This commit adds a `strnlen` length check for `server_addr` to ensure that it will not be truncated and result in a silent failure. Instead, the call to `hawkbit_set_config` will return -EINVAL if the supplied `server_addr` is too long for the internal buffer. Signed-off-by: Neal Jackson <[email protected]>
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Simplify length checks by using sizeof for the server_addr array. Signed-off-by: Neal Jackson <[email protected]>
This commit removes the requirement for DNS_RESOLVER. If DNS_RESOLVER is enabled, hawkbit uses `CONFIG_DNS_RESOLVER_MAX_QUERY_LEN` for the server_addr buffer, if disabled it uses `CONFIG_INET6_ADDRSTRLEN`. This adheres to zephyrproject-rtos#89533 which removes the requirement for DNS_RESOLVER. Signed-off-by: Neal Jackson <[email protected]>
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This PR fixes the
hb_cfg.server_addrbuffer and adds a length check when setting this value.Hawkbit uses
DNS_MAX_NAME_SIZEfor its internal buffer which is intended for a DNS response, not the query. By defaultDNS_MAX_NAME_SIZEis only 20 bytes and results in truncation for a domain name longer than that. For example, the domain name hawkbit.yourcompany.com would be truncated and fail to resolve. The KconfigDNS_RESOLVER_MAX_QUERY_LENis the correct macro to use here for a query, and is by default 256 bytes, in line with RFC1035.Since
DNS_RESOLVER_MAX_QUERY_LENis adjustable,hawkbit_set_configalso requires a length check to ensure that any domain name that is passed in can be fit in its internal buffer. This prevents silent truncation of the domain name.