diff options
Diffstat (limited to 'src/shared/dns-domain.c')
-rw-r--r-- | src/shared/dns-domain.c | 1322 |
1 files changed, 0 insertions, 1322 deletions
diff --git a/src/shared/dns-domain.c b/src/shared/dns-domain.c deleted file mode 100644 index 45d24c0079..0000000000 --- a/src/shared/dns-domain.c +++ /dev/null @@ -1,1322 +0,0 @@ -/*** - This file is part of systemd. - - Copyright 2014 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. - ***/ - -#ifdef HAVE_LIBIDN -#include <idna.h> -#include <stringprep.h> -#endif - -#include <endian.h> -#include <netinet/in.h> -#include <stdio.h> -#include <string.h> -#include <sys/socket.h> - -#include "alloc-util.h" -#include "dns-domain.h" -#include "hashmap.h" -#include "hexdecoct.h" -#include "in-addr-util.h" -#include "macro.h" -#include "parse-util.h" -#include "string-util.h" -#include "strv.h" -#include "utf8.h" - -int dns_label_unescape(const char **name, char *dest, size_t sz) { - const char *n; - char *d; - int r = 0; - - assert(name); - assert(*name); - - n = *name; - d = dest; - - for (;;) { - if (*n == '.') { - n++; - break; - } - - if (*n == 0) - break; - - if (r >= DNS_LABEL_MAX) - return -EINVAL; - - if (sz <= 0) - return -ENOBUFS; - - if (*n == '\\') { - /* Escaped character */ - - n++; - - if (*n == 0) - /* Ending NUL */ - return -EINVAL; - - else if (*n == '\\' || *n == '.') { - /* Escaped backslash or dot */ - - if (d) - *(d++) = *n; - sz--; - r++; - n++; - - } else if (n[0] >= '0' && n[0] <= '9') { - unsigned k; - - /* Escaped literal ASCII character */ - - if (!(n[1] >= '0' && n[1] <= '9') || - !(n[2] >= '0' && n[2] <= '9')) - return -EINVAL; - - k = ((unsigned) (n[0] - '0') * 100) + - ((unsigned) (n[1] - '0') * 10) + - ((unsigned) (n[2] - '0')); - - /* Don't allow anything that doesn't - * fit in 8bit. Note that we do allow - * control characters, as some servers - * (e.g. cloudflare) are happy to - * generate labels with them - * inside. */ - if (k > 255) - return -EINVAL; - - if (d) - *(d++) = (char) k; - sz--; - r++; - - n += 3; - } else - return -EINVAL; - - } else if ((uint8_t) *n >= (uint8_t) ' ' && *n != 127) { - - /* Normal character */ - - if (d) - *(d++) = *n; - sz--; - r++; - n++; - } else - return -EINVAL; - } - - /* Empty label that is not at the end? */ - if (r == 0 && *n) - return -EINVAL; - - if (sz >= 1 && d) - *d = 0; - - *name = n; - return r; -} - -/* @label_terminal: terminal character of a label, updated to point to the terminal character of - * the previous label (always skipping one dot) or to NULL if there are no more - * labels. */ -int dns_label_unescape_suffix(const char *name, const char **label_terminal, char *dest, size_t sz) { - const char *terminal; - int r; - - assert(name); - assert(label_terminal); - assert(dest); - - /* no more labels */ - if (!*label_terminal) { - if (sz >= 1) - *dest = 0; - - return 0; - } - - terminal = *label_terminal; - assert(*terminal == '.' || *terminal == 0); - - /* 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) */ - for (;;) { - if (terminal < name) { - /* Reached the first label, so indicate that there are no more */ - terminal = NULL; - break; - } - - /* Find the start of the last label */ - if (*terminal == '.') { - const char *y; - unsigned slashes = 0; - - for (y = terminal - 1; y >= name && *y == '\\'; y--) - slashes ++; - - if (slashes % 2 == 0) { - /* The '.' was not escaped */ - name = terminal + 1; - break; - } else { - terminal = y; - continue; - } - } - - terminal --; - } - - r = dns_label_unescape(&name, dest, sz); - if (r < 0) - return r; - - *label_terminal = terminal; - - return r; -} - -int dns_label_escape(const char *p, size_t l, char *dest, size_t sz) { - char *q; - - /* DNS labels must be between 1 and 63 characters long. A - * zero-length label does not exist. See RFC 2182, Section - * 11. */ - - if (l <= 0 || l > DNS_LABEL_MAX) - return -EINVAL; - if (sz < 1) - return -ENOBUFS; - - assert(p); - assert(dest); - - q = dest; - while (l > 0) { - - if (*p == '.' || *p == '\\') { - - /* Dot or backslash */ - - if (sz < 3) - return -ENOBUFS; - - *(q++) = '\\'; - *(q++) = *p; - - sz -= 2; - - } else if (*p == '_' || - *p == '-' || - (*p >= '0' && *p <= '9') || - (*p >= 'a' && *p <= 'z') || - (*p >= 'A' && *p <= 'Z')) { - - /* Proper character */ - - if (sz < 2) - return -ENOBUFS; - - *(q++) = *p; - sz -= 1; - - } else { - - /* Everything else */ - - if (sz < 5) - return -ENOBUFS; - - *(q++) = '\\'; - *(q++) = '0' + (char) ((uint8_t) *p / 100); - *(q++) = '0' + (char) (((uint8_t) *p / 10) % 10); - *(q++) = '0' + (char) ((uint8_t) *p % 10); - - sz -= 4; - } - - p++; - l--; - } - - *q = 0; - return (int) (q - dest); -} - -int dns_label_escape_new(const char *p, size_t l, char **ret) { - _cleanup_free_ char *s = NULL; - int r; - - assert(p); - assert(ret); - - if (l <= 0 || l > DNS_LABEL_MAX) - return -EINVAL; - - s = new(char, DNS_LABEL_ESCAPED_MAX); - if (!s) - return -ENOMEM; - - r = dns_label_escape(p, l, s, DNS_LABEL_ESCAPED_MAX); - if (r < 0) - return r; - - *ret = s; - s = NULL; - - return r; -} - -int dns_label_apply_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) { -#ifdef HAVE_LIBIDN - _cleanup_free_ uint32_t *input = NULL; - size_t input_size, l; - const char *p; - bool contains_8bit = false; - char buffer[DNS_LABEL_MAX+1]; - - assert(encoded); - assert(decoded); - - /* Converts an U-label into an A-label */ - - if (encoded_size <= 0) - return -EINVAL; - - for (p = encoded; p < encoded + encoded_size; p++) - if ((uint8_t) *p > 127) - contains_8bit = true; - - if (!contains_8bit) { - if (encoded_size > DNS_LABEL_MAX) - return -EINVAL; - - return 0; - } - - input = stringprep_utf8_to_ucs4(encoded, encoded_size, &input_size); - if (!input) - return -ENOMEM; - - if (idna_to_ascii_4i(input, input_size, buffer, 0) != 0) - return -EINVAL; - - l = strlen(buffer); - - /* Verify that the the result is not longer than one DNS label. */ - if (l <= 0 || l > DNS_LABEL_MAX) - return -EINVAL; - if (l > decoded_max) - return -ENOBUFS; - - memcpy(decoded, buffer, l); - - /* If there's room, append a trailing NUL byte, but only then */ - if (decoded_max > l) - decoded[l] = 0; - - return (int) l; -#else - return 0; -#endif -} - -int dns_label_undo_idna(const char *encoded, size_t encoded_size, char *decoded, size_t decoded_max) { -#ifdef HAVE_LIBIDN - size_t input_size, output_size; - _cleanup_free_ uint32_t *input = NULL; - _cleanup_free_ char *result = NULL; - uint32_t *output = NULL; - size_t w; - - /* To be invoked after unescaping. Converts an A-label into an U-label. */ - - assert(encoded); - assert(decoded); - - if (encoded_size <= 0 || encoded_size > DNS_LABEL_MAX) - return -EINVAL; - - if (encoded_size < sizeof(IDNA_ACE_PREFIX)-1) - return 0; - - if (memcmp(encoded, IDNA_ACE_PREFIX, sizeof(IDNA_ACE_PREFIX) -1) != 0) - return 0; - - input = stringprep_utf8_to_ucs4(encoded, encoded_size, &input_size); - if (!input) - return -ENOMEM; - - output_size = input_size; - output = newa(uint32_t, output_size); - - idna_to_unicode_44i(input, input_size, output, &output_size, 0); - - result = stringprep_ucs4_to_utf8(output, output_size, NULL, &w); - if (!result) - return -ENOMEM; - if (w <= 0) - return -EINVAL; - if (w > decoded_max) - return -ENOBUFS; - - memcpy(decoded, result, w); - - /* Append trailing NUL byte if there's space, but only then. */ - if (decoded_max > w) - decoded[w] = 0; - - return w; -#else - return 0; -#endif -} - -int dns_name_concat(const char *a, const char *b, char **_ret) { - _cleanup_free_ char *ret = NULL; - size_t n = 0, allocated = 0; - const char *p; - bool first = true; - int r; - - if (a) - p = a; - else if (b) { - p = b; - b = NULL; - } else - goto finish; - - for (;;) { - char label[DNS_LABEL_MAX]; - - r = dns_label_unescape(&p, label, sizeof(label)); - if (r < 0) - return r; - if (r == 0) { - if (*p != 0) - return -EINVAL; - - if (b) { - /* Now continue with the second string, if there is one */ - p = b; - b = NULL; - continue; - } - - break; - } - - if (_ret) { - if (!GREEDY_REALLOC(ret, allocated, n + !first + DNS_LABEL_ESCAPED_MAX)) - return -ENOMEM; - - r = dns_label_escape(label, r, ret + n + !first, DNS_LABEL_ESCAPED_MAX); - if (r < 0) - return r; - - if (!first) - ret[n] = '.'; - } else { - char escaped[DNS_LABEL_ESCAPED_MAX]; - - r = dns_label_escape(label, r, escaped, sizeof(escaped)); - if (r < 0) - return r; - } - - if (!first) - n++; - else - first = false; - - n += r; - } - -finish: - if (n > DNS_HOSTNAME_MAX) - return -EINVAL; - - if (_ret) { - if (n == 0) { - /* Nothing appended? If so, generate at least a single dot, to indicate the DNS root domain */ - if (!GREEDY_REALLOC(ret, allocated, 2)) - return -ENOMEM; - - ret[n++] = '.'; - } else { - if (!GREEDY_REALLOC(ret, allocated, n + 1)) - return -ENOMEM; - } - - ret[n] = 0; - *_ret = ret; - ret = NULL; - } - - return 0; -} - -void dns_name_hash_func(const void *s, struct siphash *state) { - const char *p = s; - int r; - - assert(p); - - for (;;) { - char label[DNS_LABEL_MAX+1]; - - r = dns_label_unescape(&p, label, sizeof(label)); - if (r < 0) - break; - if (r == 0) - break; - - ascii_strlower_n(label, r); - siphash24_compress(label, r, state); - siphash24_compress_byte(0, state); /* make sure foobar and foo.bar result in different hashes */ - } - - /* enforce that all names are terminated by the empty label */ - string_hash_func("", state); -} - -int dns_name_compare_func(const void *a, const void *b) { - const char *x, *y; - int r, q; - - assert(a); - assert(b); - - x = (const char *) a + strlen(a); - y = (const char *) b + strlen(b); - - for (;;) { - char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; - - if (x == NULL && y == NULL) - return 0; - - r = dns_label_unescape_suffix(a, &x, la, sizeof(la)); - q = dns_label_unescape_suffix(b, &y, lb, sizeof(lb)); - if (r < 0 || q < 0) - return r - q; - - r = ascii_strcasecmp_nn(la, r, lb, q); - if (r != 0) - return r; - } -} - -const struct hash_ops dns_name_hash_ops = { - .hash = dns_name_hash_func, - .compare = dns_name_compare_func -}; - -int dns_name_equal(const char *x, const char *y) { - int r, q; - - assert(x); - assert(y); - - for (;;) { - char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; - - r = dns_label_unescape(&x, la, sizeof(la)); - if (r < 0) - return r; - - q = dns_label_unescape(&y, lb, sizeof(lb)); - if (q < 0) - return q; - - if (r != q) - return false; - if (r == 0) - return true; - - if (ascii_strcasecmp_n(la, lb, r) != 0) - return false; - } -} - -int dns_name_endswith(const char *name, const char *suffix) { - const char *n, *s, *saved_n = NULL; - int r, q; - - assert(name); - assert(suffix); - - n = name; - s = suffix; - - for (;;) { - char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX]; - - r = dns_label_unescape(&n, ln, sizeof(ln)); - if (r < 0) - return r; - - if (!saved_n) - saved_n = n; - - q = dns_label_unescape(&s, ls, sizeof(ls)); - if (q < 0) - return q; - - if (r == 0 && q == 0) - return true; - if (r == 0 && saved_n == n) - return false; - - if (r != q || ascii_strcasecmp_n(ln, ls, r) != 0) { - - /* Not the same, let's jump back, and try with the next label again */ - s = suffix; - n = saved_n; - saved_n = NULL; - } - } -} - -int dns_name_startswith(const char *name, const char *prefix) { - const char *n, *p; - int r, q; - - assert(name); - assert(prefix); - - n = name; - p = prefix; - - for (;;) { - char ln[DNS_LABEL_MAX], lp[DNS_LABEL_MAX]; - - r = dns_label_unescape(&p, lp, sizeof(lp)); - if (r < 0) - return r; - if (r == 0) - return true; - - q = dns_label_unescape(&n, ln, sizeof(ln)); - if (q < 0) - return q; - - if (r != q) - return false; - if (ascii_strcasecmp_n(ln, lp, r) != 0) - return false; - } -} - -int dns_name_change_suffix(const char *name, const char *old_suffix, const char *new_suffix, char **ret) { - const char *n, *s, *saved_before = NULL, *saved_after = NULL, *prefix; - int r, q; - - assert(name); - assert(old_suffix); - assert(new_suffix); - assert(ret); - - n = name; - s = old_suffix; - - for (;;) { - char ln[DNS_LABEL_MAX], ls[DNS_LABEL_MAX]; - - if (!saved_before) - saved_before = n; - - r = dns_label_unescape(&n, ln, sizeof(ln)); - if (r < 0) - return r; - - if (!saved_after) - saved_after = n; - - q = dns_label_unescape(&s, ls, sizeof(ls)); - if (q < 0) - return q; - - if (r == 0 && q == 0) - break; - if (r == 0 && saved_after == n) { - *ret = NULL; /* doesn't match */ - return 0; - } - - if (r != q || ascii_strcasecmp_n(ln, ls, r) != 0) { - - /* Not the same, let's jump back, and try with the next label again */ - s = old_suffix; - n = saved_after; - saved_after = saved_before = NULL; - } - } - - /* Found it! Now generate the new name */ - prefix = strndupa(name, saved_before - name); - - r = dns_name_concat(prefix, new_suffix, ret); - if (r < 0) - return r; - - return 1; -} - -int dns_name_between(const char *a, const char *b, const char *c) { - int n; - - /* Determine if b is strictly greater than a and strictly smaller than c. - We consider the order of names to be circular, so that if a is - strictly greater than c, we consider b to be between them if it is - either greater than a or smaller than c. This is how the canonical - DNS name order used in NSEC records work. */ - - n = dns_name_compare_func(a, c); - if (n == 0) - return -EINVAL; - else if (n < 0) - /* a<---b--->c */ - return dns_name_compare_func(a, b) < 0 && - dns_name_compare_func(b, c) < 0; - else - /* <--b--c a--b--> */ - return dns_name_compare_func(b, c) < 0 || - dns_name_compare_func(a, b) < 0; -} - -int dns_name_reverse(int family, const union in_addr_union *a, char **ret) { - const uint8_t *p; - int r; - - assert(a); - assert(ret); - - p = (const uint8_t*) a; - - if (family == AF_INET) - r = asprintf(ret, "%u.%u.%u.%u.in-addr.arpa", p[3], p[2], p[1], p[0]); - else if (family == AF_INET6) - r = asprintf(ret, "%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.%c.ip6.arpa", - hexchar(p[15] & 0xF), hexchar(p[15] >> 4), hexchar(p[14] & 0xF), hexchar(p[14] >> 4), - hexchar(p[13] & 0xF), hexchar(p[13] >> 4), hexchar(p[12] & 0xF), hexchar(p[12] >> 4), - hexchar(p[11] & 0xF), hexchar(p[11] >> 4), hexchar(p[10] & 0xF), hexchar(p[10] >> 4), - hexchar(p[ 9] & 0xF), hexchar(p[ 9] >> 4), hexchar(p[ 8] & 0xF), hexchar(p[ 8] >> 4), - hexchar(p[ 7] & 0xF), hexchar(p[ 7] >> 4), hexchar(p[ 6] & 0xF), hexchar(p[ 6] >> 4), - hexchar(p[ 5] & 0xF), hexchar(p[ 5] >> 4), hexchar(p[ 4] & 0xF), hexchar(p[ 4] >> 4), - hexchar(p[ 3] & 0xF), hexchar(p[ 3] >> 4), hexchar(p[ 2] & 0xF), hexchar(p[ 2] >> 4), - hexchar(p[ 1] & 0xF), hexchar(p[ 1] >> 4), hexchar(p[ 0] & 0xF), hexchar(p[ 0] >> 4)); - else - return -EAFNOSUPPORT; - if (r < 0) - return -ENOMEM; - - return 0; -} - -int dns_name_address(const char *p, int *family, union in_addr_union *address) { - int r; - - assert(p); - assert(family); - assert(address); - - r = dns_name_endswith(p, "in-addr.arpa"); - if (r < 0) - return r; - if (r > 0) { - uint8_t a[4]; - unsigned i; - - for (i = 0; i < ELEMENTSOF(a); i++) { - char label[DNS_LABEL_MAX+1]; - - r = dns_label_unescape(&p, label, sizeof(label)); - if (r < 0) - return r; - if (r == 0) - return -EINVAL; - if (r > 3) - return -EINVAL; - - r = safe_atou8(label, &a[i]); - if (r < 0) - return r; - } - - r = dns_name_equal(p, "in-addr.arpa"); - if (r <= 0) - return r; - - *family = AF_INET; - address->in.s_addr = htobe32(((uint32_t) a[3] << 24) | - ((uint32_t) a[2] << 16) | - ((uint32_t) a[1] << 8) | - (uint32_t) a[0]); - - return 1; - } - - r = dns_name_endswith(p, "ip6.arpa"); - if (r < 0) - return r; - if (r > 0) { - struct in6_addr a; - unsigned i; - - for (i = 0; i < ELEMENTSOF(a.s6_addr); i++) { - char label[DNS_LABEL_MAX+1]; - int x, y; - - r = dns_label_unescape(&p, label, sizeof(label)); - if (r <= 0) - return r; - if (r != 1) - return -EINVAL; - x = unhexchar(label[0]); - if (x < 0) - return -EINVAL; - - r = dns_label_unescape(&p, label, sizeof(label)); - if (r <= 0) - return r; - if (r != 1) - return -EINVAL; - y = unhexchar(label[0]); - if (y < 0) - return -EINVAL; - - a.s6_addr[ELEMENTSOF(a.s6_addr) - i - 1] = (uint8_t) y << 4 | (uint8_t) x; - } - - r = dns_name_equal(p, "ip6.arpa"); - if (r <= 0) - return r; - - *family = AF_INET6; - address->in6 = a; - return 1; - } - - return 0; -} - -bool dns_name_is_root(const char *name) { - - assert(name); - - /* There are exactly two ways to encode the root domain name: - * as empty string, or with a single dot. */ - - return STR_IN_SET(name, "", "."); -} - -bool dns_name_is_single_label(const char *name) { - int r; - - assert(name); - - r = dns_name_parent(&name); - if (r <= 0) - return false; - - return dns_name_is_root(name); -} - -/* Encode a domain name according to RFC 1035 Section 3.1, without compression */ -int dns_name_to_wire_format(const char *domain, uint8_t *buffer, size_t len, bool canonical) { - uint8_t *label_length, *out; - int r; - - assert(domain); - assert(buffer); - - out = buffer; - - do { - /* Reserve a byte for label length */ - if (len <= 0) - return -ENOBUFS; - len--; - label_length = out; - out++; - - /* Convert and copy a single label. Note that - * dns_label_unescape() returns 0 when it hits the end - * of the domain name, which we rely on here to encode - * the trailing NUL byte. */ - r = dns_label_unescape(&domain, (char *) out, len); - if (r < 0) - return r; - - /* Optionally, output the name in DNSSEC canonical - * format, as described in RFC 4034, section 6.2. Or - * in other words: in lower-case. */ - if (canonical) - ascii_strlower_n((char*) out, (size_t) r); - - /* Fill label length, move forward */ - *label_length = r; - out += r; - len -= r; - - } while (r != 0); - - /* Verify the maximum size of the encoded name. The trailing - * dot + NUL byte account are included this time, hence - * compare against DNS_HOSTNAME_MAX + 2 (which is 255) this - * time. */ - if (out - buffer > DNS_HOSTNAME_MAX + 2) - return -EINVAL; - - return out - buffer; -} - -static bool srv_type_label_is_valid(const char *label, size_t n) { - size_t k; - - assert(label); - - if (n < 2) /* Label needs to be at least 2 chars long */ - return false; - - if (label[0] != '_') /* First label char needs to be underscore */ - return false; - - /* Second char must be a letter */ - if (!(label[1] >= 'A' && label[1] <= 'Z') && - !(label[1] >= 'a' && label[1] <= 'z')) - return false; - - /* Third and further chars must be alphanumeric or a hyphen */ - for (k = 2; k < n; k++) { - if (!(label[k] >= 'A' && label[k] <= 'Z') && - !(label[k] >= 'a' && label[k] <= 'z') && - !(label[k] >= '0' && label[k] <= '9') && - label[k] != '-') - return false; - } - - return true; -} - -bool dns_srv_type_is_valid(const char *name) { - unsigned c = 0; - int r; - - if (!name) - return false; - - for (;;) { - char label[DNS_LABEL_MAX]; - - /* This more or less implements RFC 6335, Section 5.1 */ - - r = dns_label_unescape(&name, label, sizeof(label)); - if (r < 0) - return false; - if (r == 0) - break; - - if (c >= 2) - return false; - - if (!srv_type_label_is_valid(label, r)) - return false; - - c++; - } - - return c == 2; /* exactly two labels */ -} - -bool dns_service_name_is_valid(const char *name) { - size_t l; - - /* This more or less implements RFC 6763, Section 4.1.1 */ - - if (!name) - return false; - - if (!utf8_is_valid(name)) - return false; - - if (string_has_cc(name, NULL)) - return false; - - l = strlen(name); - if (l <= 0) - return false; - if (l > 63) - return false; - - return true; -} - -int dns_service_join(const char *name, const char *type, const char *domain, char **ret) { - char escaped[DNS_LABEL_ESCAPED_MAX]; - _cleanup_free_ char *n = NULL; - int r; - - assert(type); - assert(domain); - assert(ret); - - if (!dns_srv_type_is_valid(type)) - return -EINVAL; - - if (!name) - return dns_name_concat(type, domain, ret); - - if (!dns_service_name_is_valid(name)) - return -EINVAL; - - r = dns_label_escape(name, strlen(name), escaped, sizeof(escaped)); - if (r < 0) - return r; - - r = dns_name_concat(type, domain, &n); - if (r < 0) - return r; - - return dns_name_concat(escaped, n, ret); -} - -static bool dns_service_name_label_is_valid(const char *label, size_t n) { - char *s; - - assert(label); - - if (memchr(label, 0, n)) - return false; - - s = strndupa(label, n); - return dns_service_name_is_valid(s); -} - -int dns_service_split(const char *joined, char **_name, char **_type, char **_domain) { - _cleanup_free_ char *name = NULL, *type = NULL, *domain = NULL; - const char *p = joined, *q = NULL, *d = NULL; - char a[DNS_LABEL_MAX], b[DNS_LABEL_MAX], c[DNS_LABEL_MAX]; - int an, bn, cn, r; - unsigned x = 0; - - assert(joined); - - /* Get first label from the full name */ - an = dns_label_unescape(&p, a, sizeof(a)); - if (an < 0) - return an; - - if (an > 0) { - x++; - - /* If there was a first label, try to get the second one */ - bn = dns_label_unescape(&p, b, sizeof(b)); - if (bn < 0) - return bn; - - if (bn > 0) { - x++; - - /* If there was a second label, try to get the third one */ - q = p; - cn = dns_label_unescape(&p, c, sizeof(c)); - if (cn < 0) - return cn; - - if (cn > 0) - x++; - } else - cn = 0; - } else - an = 0; - - if (x >= 2 && srv_type_label_is_valid(b, bn)) { - - if (x >= 3 && srv_type_label_is_valid(c, cn)) { - - if (dns_service_name_label_is_valid(a, an)) { - /* OK, got <name> . <type> . <type2> . <domain> */ - - name = strndup(a, an); - if (!name) - return -ENOMEM; - - type = strjoin(b, ".", c, NULL); - if (!type) - return -ENOMEM; - - d = p; - goto finish; - } - - } else if (srv_type_label_is_valid(a, an)) { - - /* OK, got <type> . <type2> . <domain> */ - - name = NULL; - - type = strjoin(a, ".", b, NULL); - if (!type) - return -ENOMEM; - - d = q; - goto finish; - } - } - - name = NULL; - type = NULL; - d = joined; - -finish: - r = dns_name_normalize(d, &domain); - if (r < 0) - return r; - - if (_domain) { - *_domain = domain; - domain = NULL; - } - - if (_type) { - *_type = type; - type = NULL; - } - - if (_name) { - *_name = name; - name = NULL; - } - - return 0; -} - -static int dns_name_build_suffix_table(const char *name, const char*table[]) { - const char *p; - unsigned n = 0; - int r; - - assert(name); - assert(table); - - p = name; - for (;;) { - if (n > DNS_N_LABELS_MAX) - return -EINVAL; - - table[n] = p; - r = dns_name_parent(&p); - if (r < 0) - return r; - if (r == 0) - break; - - n++; - } - - return (int) n; -} - -int dns_name_suffix(const char *name, unsigned n_labels, const char **ret) { - const char* labels[DNS_N_LABELS_MAX+1]; - int n; - - assert(name); - assert(ret); - - n = dns_name_build_suffix_table(name, labels); - if (n < 0) - return n; - - if ((unsigned) n < n_labels) - return -EINVAL; - - *ret = labels[n - n_labels]; - return (int) (n - n_labels); -} - -int dns_name_skip(const char *a, unsigned n_labels, const char **ret) { - int r; - - assert(a); - assert(ret); - - for (; n_labels > 0; n_labels --) { - r = dns_name_parent(&a); - if (r < 0) - return r; - if (r == 0) { - *ret = ""; - return 0; - } - } - - *ret = a; - return 1; -} - -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); - - r = dns_name_skip(a, n_labels, &a); - if (r <= 0) - return r; - - return dns_name_equal(a, b); -} - -int dns_name_common_suffix(const char *a, const char *b, const char **ret) { - const char *a_labels[DNS_N_LABELS_MAX+1], *b_labels[DNS_N_LABELS_MAX+1]; - int n = 0, m = 0, k = 0, r, q; - - assert(a); - assert(b); - assert(ret); - - /* Determines the common suffix of domain names a and b */ - - n = dns_name_build_suffix_table(a, a_labels); - if (n < 0) - return n; - - m = dns_name_build_suffix_table(b, b_labels); - if (m < 0) - return m; - - for (;;) { - char la[DNS_LABEL_MAX], lb[DNS_LABEL_MAX]; - const char *x, *y; - - if (k >= n || k >= m) { - *ret = a_labels[n - k]; - return 0; - } - - x = a_labels[n - 1 - k]; - r = dns_label_unescape(&x, la, sizeof(la)); - if (r < 0) - return r; - - y = b_labels[m - 1 - k]; - q = dns_label_unescape(&y, lb, sizeof(lb)); - if (q < 0) - return q; - - if (r != q || ascii_strcasecmp_n(la, lb, r) != 0) { - *ret = a_labels[n - k]; - return 0; - } - - k++; - } -} - -int dns_name_apply_idna(const char *name, char **ret) { - _cleanup_free_ char *buf = NULL; - size_t n = 0, allocated = 0; - bool first = true; - int r, q; - - assert(name); - assert(ret); - - for (;;) { - char label[DNS_LABEL_MAX]; - - r = dns_label_unescape(&name, label, sizeof(label)); - if (r < 0) - return r; - if (r == 0) - break; - - q = dns_label_apply_idna(label, r, label, sizeof(label)); - if (q < 0) - return q; - if (q > 0) - r = q; - - if (!GREEDY_REALLOC(buf, allocated, n + !first + DNS_LABEL_ESCAPED_MAX)) - return -ENOMEM; - - r = dns_label_escape(label, r, buf + n + !first, DNS_LABEL_ESCAPED_MAX); - if (r < 0) - return r; - - if (first) - first = false; - else - buf[n++] = '.'; - - n +=r; - } - - if (n > DNS_HOSTNAME_MAX) - return -EINVAL; - - if (!GREEDY_REALLOC(buf, allocated, n + 1)) - return -ENOMEM; - - buf[n] = 0; - *ret = buf; - buf = NULL; - - return (int) n; -} |