diff options
Diffstat (limited to 'src/basic/hostname-util.c')
| -rw-r--r-- | src/basic/hostname-util.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/src/basic/hostname-util.c b/src/basic/hostname-util.c index dc5434fcd1..1b816fb77a 100644 --- a/src/basic/hostname-util.c +++ b/src/basic/hostname-util.c @@ -62,16 +62,19 @@ static bool hostname_valid_char(char c) { } /** - * Check if s looks like a valid host name or fqdn. This does not do + * Check if s looks like a valid host name or FQDN. This does not do * full DNS validation, but only checks if the name is composed of * allowed characters and the length is not above the maximum allowed * by Linux (c.f. dns_name_is_valid()). Trailing dot is allowed if - * relax is true and at least two components are present in the name. + * allow_trailing_dot is true and at least two components are present + * in the name. Note that due to the restricted charset and length + * this call is substantially more conservative than + * dns_domain_is_valid(). */ -bool hostname_is_valid(const char *s, bool relax) { +bool hostname_is_valid(const char *s, bool allow_trailing_dot) { + unsigned n_dots = 0; const char *p; bool dot; - unsigned dots = 0; if (isempty(s)) return false; @@ -87,7 +90,7 @@ bool hostname_is_valid(const char *s, bool relax) { return false; dot = true; - dots ++; + n_dots ++; } else { if (!hostname_valid_char(*p)) return false; @@ -96,10 +99,12 @@ bool hostname_is_valid(const char *s, bool relax) { } } - if (dot && (dots < 2 || !relax)) + if (dot && (n_dots < 2 || !allow_trailing_dot)) return false; - if (p-s > HOST_NAME_MAX) + if (p-s > HOST_NAME_MAX) /* Note that HOST_NAME_MAX is 64 on + * Linux, but DNS allows domain names + * up to 255 characters */ return false; return true; |