diff options
Diffstat (limited to 'src/shared')
| -rw-r--r-- | src/shared/dns-domain.c | 94 | ||||
| -rw-r--r-- | src/shared/dns-domain.h | 8 |
2 files changed, 94 insertions, 8 deletions
diff --git a/src/shared/dns-domain.c b/src/shared/dns-domain.c index c46f7d21b7..0273b9e3c9 100644 --- a/src/shared/dns-domain.c +++ b/src/shared/dns-domain.c @@ -154,20 +154,24 @@ int dns_label_unescape_suffix(const char *name, const char **label_terminal, cha return 0; } - assert(**label_terminal == '.' || **label_terminal == 0); + terminal = *label_terminal; + assert(*terminal == '.' || *terminal == 0); - /* skip current terminal character */ - terminal = *label_terminal - 1; + /* Skip current terminal character (and accept domain names ending it ".") */ + if (*terminal == 0) + terminal--; + if (terminal >= name && *terminal == '.') + terminal--; - /* point name to the last label, and terminal to the preceding terminal symbol (or make it a NULL pointer) */ + /* Point name to the last label, and terminal to the preceding terminal symbol (or make it a NULL pointer) */ for (;;) { if (terminal < name) { - /* reached the first label, so indicate that there are no more */ + /* Reached the first label, so indicate that there are no more */ terminal = NULL; break; } - /* find the start of the last label */ + /* Find the start of the last label */ if (*terminal == '.') { const char *y; unsigned slashes = 0; @@ -176,7 +180,7 @@ int dns_label_unescape_suffix(const char *name, const char **label_terminal, cha slashes ++; if (slashes % 2 == 0) { - /* the '.' was not escaped */ + /* The '.' was not escaped */ name = terminal + 1; break; } else { @@ -533,7 +537,7 @@ int dns_name_compare_func(const void *a, const void *b) { if (k > 0) r = k; if (w > 0) - r = w; + q = w; la[r] = lb[q] = 0; r = strcasecmp(la, lb); @@ -1159,3 +1163,77 @@ finish: return 0; } + +int dns_name_suffix(const char *name, unsigned n_labels, const char **ret) { + const char* labels[DNS_N_LABELS_MAX+1]; + unsigned n = 0; + const char *p; + int r; + + assert(name); + assert(ret); + + p = name; + for (;;) { + if (n > DNS_N_LABELS_MAX) + return -EINVAL; + + labels[n] = p; + + r = dns_name_parent(&p); + if (r < 0) + return r; + if (r == 0) + break; + + n++; + } + + if (n < n_labels) + return -EINVAL; + + *ret = labels[n - n_labels]; + return (int) (n - n_labels); +} + +int dns_name_count_labels(const char *name) { + unsigned n = 0; + const char *p; + int r; + + assert(name); + + p = name; + for (;;) { + r = dns_name_parent(&p); + if (r < 0) + return r; + if (r == 0) + break; + + if (n >= DNS_N_LABELS_MAX) + return -EINVAL; + + n++; + } + + return (int) n; +} + +int dns_name_equal_skip(const char *a, unsigned n_labels, const char *b) { + int r; + + assert(a); + assert(b); + + while (n_labels > 0) { + + r = dns_name_parent(&a); + if (r <= 0) + return r; + + n_labels --; + } + + return dns_name_equal(a, b); +} diff --git a/src/shared/dns-domain.h b/src/shared/dns-domain.h index 02b51832b6..dd8ae3ac98 100644 --- a/src/shared/dns-domain.h +++ b/src/shared/dns-domain.h @@ -42,6 +42,9 @@ /* Maximum length of a full hostname, on the wire, including the final NUL byte */ #define DNS_WIRE_FOMAT_HOSTNAME_MAX 255 +/* Maximum number of labels per valid hostname */ +#define DNS_N_LABELS_MAX 127 + int dns_label_unescape(const char **name, char *dest, size_t sz); int dns_label_unescape_suffix(const char *name, const char **label_end, char *dest, size_t sz); int dns_label_escape(const char *p, size_t l, char *dest, size_t sz); @@ -96,3 +99,8 @@ bool dns_service_name_is_valid(const char *name); int dns_service_join(const char *name, const char *type, const char *domain, char **ret); int dns_service_split(const char *joined, char **name, char **type, char **domain); + +int dns_name_suffix(const char *name, unsigned n_labels, const char **ret); +int dns_name_count_labels(const char *name); + +int dns_name_equal_skip(const char *a, unsigned n_labels, const char *b); |