diff options
Diffstat (limited to 'src/resolve/resolved-dns-domain.c')
-rw-r--r-- | src/resolve/resolved-dns-domain.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/src/resolve/resolved-dns-domain.c b/src/resolve/resolved-dns-domain.c new file mode 100644 index 0000000000..94ffc0fac4 --- /dev/null +++ b/src/resolve/resolved-dns-domain.c @@ -0,0 +1,381 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + 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/>. + ***/ + +#include "resolved-dns-domain.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); + assert(dest); + + n = *name; + d = dest; + + for (;;) { + if (*n == '.') { + n++; + break; + } + + if (*n == 0) + break; + + if (sz <= 0) + return -ENOSPC; + + if (*n == '\\') { + /* Escaped character */ + + n++; + + if (*n == 0) + /* Ending NUL */ + return -EINVAL; + + else if (*n == '\\' || *n == '.') { + /* Escaped backslash or dot */ + *(d++) = *(n++); + sz--; + r++; + + } 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 CC characters or anything that doesn't fit in 8bit */ + if (k < ' ' || k > 255 || k == 127) + return -EINVAL; + + *(d++) = (char) k; + sz--; + r++; + + n += 3; + } else + return -EINVAL; + + } else if (*n >= ' ' && *n != 127) { + + /* Normal character */ + *(d++) = *(n++); + sz--; + r++; + } else + return -EINVAL; + } + + /* Empty label that is not at the end? */ + if (r == 0 && *n) + return -EINVAL; + + if (sz >= 1) + *d = 0; + + *name = n; + return r; +} + +int dns_label_escape(const char *p, size_t l, char **ret) { + _cleanup_free_ char *s = NULL; + char *q; + int r; + + assert(p); + assert(ret); + + s = malloc(l * 4 + 1); + if (!s) + return -ENOMEM; + + q = s; + while (l > 0) { + + if (*p == '.' || *p == '\\') { + + /* Dot or backslash */ + *(q++) = '\\'; + *(q++) = *p; + + } else if (*p == '_' || + *p == '-' || + (*p >= '0' && *p <= '9') || + (*p >= 'a' && *p <= 'z') || + (*p >= 'A' && *p <= 'Z')) { + + /* Proper character */ + *(q++) = *p; + } else if (*p >= ' ' && *p != 127) { + + /* Everything else */ + *(q++) = '\\'; + *(q++) = '0' + (char) ((unsigned) *p / 100); + *(q++) = '0' + (char) (((unsigned) *p / 10) % 10); + *(q++) = '0' + (char) ((unsigned) *p % 10); + + } else + return -EINVAL; + + p++; + l--; + } + + *q = 0; + *ret = s; + r = q - s; + s = NULL; + + return r; +} + +int dns_name_normalize(const char *s, char **_ret) { + _cleanup_free_ char *ret = NULL; + size_t n = 0, allocated = 0; + const char *p = s; + bool first = true; + int r; + + assert(s); + assert(_ret); + + for (;;) { + _cleanup_free_ char *t = NULL; + 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; + break; + } + + r = dns_label_escape(label, r, &t); + if (r < 0) + return r; + + if (!GREEDY_REALLOC(ret, allocated, n + !first + strlen(t) + 1)) + return -ENOMEM; + + if (!first) + ret[n++] = '.'; + else + first = false; + + memcpy(ret + n, t, r); + n += r; + } + + if (!GREEDY_REALLOC(ret, allocated, n + 1)) + return -ENOMEM; + + ret[n] = 0; + *_ret = ret; + ret = NULL; + + return 0; +} + +unsigned long dns_name_hash_func(const void *s, const uint8_t hash_key[HASH_KEY_SIZE]) { + const char *p = s; + unsigned long ul = 0; + int r; + + assert(p); + + while (*p) { + char label[DNS_LABEL_MAX+1]; + + r = dns_label_unescape(&p, label, sizeof(label)); + if (r < 0) + break; + + label[r] = 0; + ascii_strlower(label); + + ul = hash_key[0] * ul + ul + string_hash_func(label, hash_key); + } + + return ul; +} + +int dns_name_compare_func(const void *a, const void *b) { + const char *x = a, *y = b; + int r, q; + + assert(a); + assert(b); + + for (;;) { + char la[DNS_LABEL_MAX+1], lb[DNS_LABEL_MAX+1]; + + if (*x == 0 && *y == 0) + return 0; + + r = dns_label_unescape(&x, la, sizeof(la)); + q = dns_label_unescape(&y, lb, sizeof(lb)); + if (r < 0 || q < 0) + return r - q; + + la[r] = lb[q] = 0; + r = strcasecmp(la, lb); + if (r != 0) + return r; + } +} + +int dns_name_equal(const char *x, const char *y) { + int r, q; + + assert(x); + assert(y); + + for (;;) { + char la[DNS_LABEL_MAX+1], lb[DNS_LABEL_MAX+1]; + + if (*x == 0 && *y == 0) + return true; + + 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; + + la[r] = lb[q] = 0; + if (strcasecmp(la, lb)) + 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+1], ls[DNS_LABEL_MAX+1]; + + 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 (r < 0) + return r; + + if (r == 0 && q == 0) + return true; + if (r == 0 && saved_n == n) + return false; + + ln[r] = ls[q] = 0; + + if (r != q || strcasecmp(ln, ls)) { + + /* 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_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.ip6.arpa", + hexchar(p[15]), hexchar(p[14]), hexchar(p[13]), hexchar(p[12]), + hexchar(p[11]), hexchar(p[10]), hexchar(p[ 9]), hexchar(p[ 8]), + hexchar(p[ 7]), hexchar(p[ 6]), hexchar(p[ 5]), hexchar(p[ 4]), + hexchar(p[ 3]), hexchar(p[ 2]), hexchar(p[ 1]), hexchar(p[ 0])); + else + return -EAFNOSUPPORT; + if (r < 0) + return -ENOMEM; + + return 0; +} + +int dns_name_root(const char *name) { + char label[DNS_LABEL_MAX+1]; + int r; + + assert(name); + + r = dns_label_unescape(&name, label, sizeof(label)); + if (r < 0) + return r; + + return r == 0 && *name == 0; +} + +int dns_name_single_label(const char *name) { + char label[DNS_LABEL_MAX+1]; + int r; + + assert(name); + + r = dns_label_unescape(&name, label, sizeof(label)); + if (r < 0) + return r; + + if (r == 0) + return 0; + + r = dns_label_unescape(&name, label, sizeof(label)); + if (r < 0) + return r; + + return r == 0 && *name == 0; +} |