--- /dev/null
+/*
+ * Copyright (c) 2018, JANET(UK)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of JANET(UK) nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <tr_name_internal.h>
+#include <arpa/inet.h>
+#include <stdlib.h>
+#include <string.h>
+#include <talloc.h>
+
+#include <tr_inet_util.h>
+#include <errno.h>
+
+/**
+ * Determine whether a string is a valid address of a given family
+ *
+ * @param s string to check
+ * @param af address family (probably AF_INET or AF_INET6)
+ * @return 1 if string is a valid address in the given family, 0 if not, -1 on error (errno set)
+ */
+static int is_valid_address(int af, const char *s)
+{
+ unsigned char buf[sizeof(struct in6_addr)];
+
+ if (s == NULL)
+ return 0;
+ return inet_pton(af, s, buf);
+}
+
+/**
+ * Determine whether a string is a valid IPv6 address reference
+ *
+ * I.e., an IPv6 address in brackets
+ *
+ * @param s string to validate
+ * @return 1 if a valid reference, 0 otherwise
+ */
+static int tr_valid_ipv6_reference(const char *s)
+{
+ char *cpy;
+ size_t len;
+ int valid_ipv6;
+
+ /* check that it starts with an open bracket */
+ if (*s != '[')
+ return 0;
+
+ /* check that it ends with a close bracket */
+ len = strlen(s);
+ if (*(s+len-1) != ']')
+ return 0;
+
+ /* make a null-terminated copy of the string omitting the brackets */
+ cpy = talloc_strndup(NULL, s+1, len-2);
+ if (cpy == NULL)
+ return 0; /* an error occurred - fail safe */
+
+ valid_ipv6 = is_valid_address(AF_INET6, cpy);
+ talloc_free(cpy);
+
+ return valid_ipv6;
+}
+
+/**
+ * Validate a host string
+ *
+ * The intention is to reject strings that may appear to contain a ':port' spec.
+ * Takes a permissive view of valid: a hostname is valid if either it is a
+ * bracketed IPv6 address reference ([address]) or has no brackets or colons.
+ * This accepts all valid DNS names and IPv4 addresses, as well as many invalid
+ * hostnames. This is ok for accepting a hostname that will later be resolved
+ * because invalid names will fail to resolve. It should *not* be used to ensure
+ * a hostname is compliant with RFC!
+ *
+ * Ignores a trailing colon followed by decimal digits.
+ *
+ * @param s string to validate
+ * @return 1 if a valid host specification, 0 otherwise
+ */
+static int tr_valid_host(const char *s)
+{
+ if (strchr(s, '[') || strchr(s, ']') || strchr(s, ':'))
+ return tr_valid_ipv6_reference(s);
+
+ return 1;
+}
+
+/**
+ * Check that all characters are decimal digits
+ *
+ * @param s
+ * @return 1 if all digits, 0 otherwise
+ */
+static int tr_str_all_digits(const char *s)
+{
+ if (s == NULL)
+ return 0;
+
+ for( ; *s; s++) {
+ if ( (*s < '0') || (*s > '9'))
+ return 0;
+ }
+
+ return 1;
+}
+
+/**
+ * Validate and parse a hostname or hostname/port
+ *
+ * If port_out is not null, accepts a port as well. This is
+ * stored in *port_out. If no port is given, a 0 is stored.
+ * If an invalid port is given, -1 is stored.
+ *
+ * If the hostname is invalid, null is returned and no value
+ * is written to *port_out.
+ *
+ * If port_out is null, null will be returned if the string
+ * contains a port.
+ *
+ * The return value must be freed with talloc_free unless
+ * it is null.
+ *
+ * @param mem_ctx talloc context for hostname result
+ * @param s string to parse
+ * @param port_out pointer to an allocated integer, or NULL
+ * @return pointer to the hostname or null on error
+ */
+char *tr_parse_host(TALLOC_CTX *mem_ctx, const char *s, int *port_out)
+{
+ const char *colon;
+ char *hostname;
+ int port;
+
+ if (s == NULL)
+ return NULL;
+
+ /* If we are accepting a port, find the last colon. */
+ if (port_out == NULL)
+ colon = NULL;
+ else
+ colon = strrchr(s, ':');
+
+ /* Get a copy of the hostname portion, which may be the entire string. */
+ if (colon == NULL)
+ hostname = talloc_strdup(NULL, s);
+ else
+ hostname = talloc_strndup(NULL, s, colon-s);
+
+ if (hostname == NULL)
+ return NULL; /* failed to dup the hostname */
+
+ /* Check that the hostname is valid; if not, return null and ignore the port. */
+ if (! tr_valid_host(hostname)) {
+ talloc_free(hostname);
+ return NULL;
+ }
+
+ /* If we are accepting a port, parse and validate it. */
+ if (port_out != NULL) {
+ if (colon == NULL) {
+ *port_out = 0;
+ } else {
+ port = tr_parse_port(colon+1);
+ if ((port > 0) && tr_str_all_digits(colon+1))
+ *port_out = port;
+ else
+ *port_out = -1;
+ }
+ }
+
+ return hostname;
+}
+
+TR_NAME *tr_hostname_and_port_to_name(TR_NAME *hn, int port)
+{
+ TR_NAME *retval = NULL;
+ char *s = NULL;
+ char *hn_s = tr_name_strdup(hn);
+
+ if (!hn_s)
+ return NULL;
+
+ s = talloc_asprintf(NULL, "%s:%d", hn_s, port);
+ free(hn_s);
+
+ if (s) {
+ retval = tr_new_name(s);
+ talloc_free(s);
+ }
+
+ return retval;
+}
+
+/**
+ * Parse a string containing a port
+ *
+ * Returns the port number, which is always in the range 1-65535.
+ * On error, returns < 0. The absolute value is an error code from errno.h
+ *
+ * @param s
+ * @return port number or < 0 on error
+ */
+int tr_parse_port(const char *s)
+{
+ long port;
+ char *end;
+
+ errno = 0; /* strtol sets this, make sure it's zero to avoid false positives */
+ port = strtol(s, &end, 10);
+ if (errno) {
+ return -errno;
+ }
+
+ if (*end != '\0') {
+ return -EINVAL;
+ }
+
+ if ((port <= 0) || (port > 65535)) {
+ return -ERANGE;
+ }
+
+ return (int) port;
+}
\ No newline at end of file
projects / trust_router.git / blobdiff