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diff --git a/libsylph/ssl_hostname_validation.c b/libsylph/ssl_hostname_validation.c
new file mode 100644
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+++ b/libsylph/ssl_hostname_validation.c
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+/*
+ * Helper functions to perform basic hostname validation using OpenSSL.
+ *
+ * Copyright (C) 2012, iSEC Partners.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ + use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is furnished to do
+ + so, subject to the following conditions:
+ +
+ + The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Author:  Alban Diquet
+ *
+ * https://github.com/iSECPartners/ssl-conservatory
+ *
+ * Modified naming convention to match LibSylph.
+ *
+ */
+ 
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#if USE_SSL
+
+#include <glib.h>
+
+#include <strings.h>
+#include <openssl/x509v3.h>
+#include <openssl/ssl.h>
+
+#include "utils.h"
+#include "ssl_hostname_validation.h"
+
+
+#define HOSTNAME_MAX_SIZE 255
+
+
+/* The following host_match() function is based on cURL/libcurl code. */
+
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+/***************************************************************************
+ *
+ * COPYRIGHT AND PERMISSION NOTICE
+ *
+ * Copyright (c) 1996 - 2014, Daniel Stenberg, <daniel@haxx.se>.
+ *
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software for any purpose
+ * with or without fee is hereby granted, provided that the above copyright
+ * notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. IN
+ * NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
+ * OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of a copyright holder shall not
+ * be used in advertising or otherwise to promote the sale, use or other dealings
+ * in this Software without prior written authorization of the copyright holder.
+ *
+ ***************************************************************************/
+
+/**
+* Match a hostname against a wildcard pattern.
+* E.g.
+*  "foo.host.com" matches "*.host.com".
+*
+* We use the matching rule described in RFC6125, section 6.4.3.
+* http://tools.ietf.org/html/rfc6125#section-6.4.3
+*/
+
+static int host_match(const char *hostname, const char *pattern)
+{
+        const char *pattern_label_end, *pattern_wildcard, *hostname_label_end;
+        size_t prefixlen, suffixlen;
+
+        if (!pattern || !*pattern || !hostname || !*hostname)
+                return SSL_HOSTNAME_MATCH_NOT_FOUND;
+
+        /* trivial case */
+        if (g_ascii_strcasecmp(pattern, hostname) == 0)
+                return SSL_HOSTNAME_MATCH_FOUND;
+
+        pattern_wildcard = strchr(pattern, '*');
+        if (pattern_wildcard == NULL) {
+                return g_ascii_strcasecmp(pattern, hostname) == 0 ?
+                        SSL_HOSTNAME_MATCH_FOUND : SSL_HOSTNAME_MATCH_NOT_FOUND;
+        }
+
+        /* We require at least 2 dots in pattern to avoid too wide wildcard
+           match. */
+        pattern_label_end = strchr(pattern, '.');
+        if (pattern_label_end == NULL ||
+            strchr(pattern_label_end + 1, '.') == NULL ||
+            pattern_wildcard > pattern_label_end ||
+            g_ascii_strncasecmp(pattern, "xn--", 4) == 0) {
+                return g_ascii_strcasecmp(pattern, hostname) == 0 ?
+                SSL_HOSTNAME_MATCH_FOUND : SSL_HOSTNAME_MATCH_NOT_FOUND;
+        }
+
+        hostname_label_end = strchr(hostname, '.');
+        if (hostname_label_end == NULL ||
+            g_ascii_strcasecmp(pattern_label_end, hostname_label_end) != 0)
+                return SSL_HOSTNAME_MATCH_NOT_FOUND;
+
+        /* The wildcard must match at least one character, so the left-most
+           label of the hostname is at least as large as the left-most label
+           of the pattern. */
+        if (hostname_label_end - hostname < pattern_label_end - pattern)
+                return SSL_HOSTNAME_MATCH_NOT_FOUND;
+
+        prefixlen = pattern_wildcard - pattern;
+        suffixlen = pattern_label_end - (pattern_wildcard + 1);
+        return g_ascii_strncasecmp(pattern, hostname, prefixlen) == 0 &&
+               g_ascii_strncasecmp(pattern_wildcard + 1, hostname_label_end - suffixlen, suffixlen) == 0 ?
+                SSL_HOSTNAME_MATCH_FOUND : SSL_HOSTNAME_MATCH_NOT_FOUND;
+}
+
+
+/**
+* Tries to find a match for hostname in the certificate's Common Name field.
+*
+* Returns MatchFound if a match was found.
+* Returns MatchNotFound if no matches were found.
+* Returns MalformedCertificate if the Common Name had a NUL character embedded in it.
+* Returns Error if the Common Name could not be extracted.
+*/
+static SSLHostnameValidationResult matches_common_name(const char *hostname, const X509 *server_cert) {
+        int common_name_loc = -1;
+        X509_NAME_ENTRY *common_name_entry = NULL;
+        ASN1_STRING *common_name_asn1 = NULL;
+        char *common_name_str = NULL;
+
+        // Find the position of the CN field in the Subject field of the certificate
+        common_name_loc = X509_NAME_get_index_by_NID(X509_get_subject_name((X509 *) server_cert), NID_commonName, -1);
+        if (common_name_loc < 0) {
+                return SSL_HOSTNAME_ERROR;
+        }
+
+        // Extract the CN field
+        common_name_entry = X509_NAME_get_entry(X509_get_subject_name((X509 *) server_cert), common_name_loc);
+        if (common_name_entry == NULL) {
+                return SSL_HOSTNAME_ERROR;
+        }
+
+        // Convert the CN field to a C string
+        common_name_asn1 = X509_NAME_ENTRY_get_data(common_name_entry);
+        if (common_name_asn1 == NULL) {
+                return SSL_HOSTNAME_ERROR;
+        }                       
+        common_name_str = (char *) ASN1_STRING_data(common_name_asn1);
+
+        debug_print("matches_common_name: %s\n", common_name_str);
+
+        // Make sure there isn't an embedded NUL character in the CN
+        if (ASN1_STRING_length(common_name_asn1) != strlen(common_name_str)) {
+                return SSL_HOSTNAME_MALFORMED_CERTIFICATE;
+        }
+
+        // Compare expected hostname with the CN
+        return host_match(hostname, common_name_str);
+}
+
+
+/**
+* Tries to find a match for hostname in the certificate's Subject Alternative Name extension.
+*
+* Returns MatchFound if a match was found.
+* Returns MatchNotFound if no matches were found.
+* Returns MalformedCertificate if any of the hostnames had a NUL character embedded in it.
+* Returns NoSANPresent if the SAN extension was not present in the certificate.
+*/
+static SSLHostnameValidationResult matches_subject_alternative_name(const char *hostname, const X509 *server_cert) {
+        SSLHostnameValidationResult result = SSL_HOSTNAME_MATCH_NOT_FOUND;
+        int i;
+        int san_names_nb = -1;
+        STACK_OF(GENERAL_NAME) *san_names = NULL;
+
+        // Try to extract the names within the SAN extension from the certificate
+        san_names = X509_get_ext_d2i((X509 *) server_cert, NID_subject_alt_name, NULL, NULL);
+        if (san_names == NULL) {
+                return SSL_HOSTNAME_NO_SAN_PRESENT;
+        }
+        san_names_nb = sk_GENERAL_NAME_num(san_names);
+
+        // Check each name within the extension
+        for (i=0; i<san_names_nb; i++) {
+                const GENERAL_NAME *current_name = sk_GENERAL_NAME_value(san_names, i);
+
+                if (current_name->type == GEN_DNS) {
+                        // Current name is a DNS name, let's check it
+                        char *dns_name = (char *) ASN1_STRING_data(current_name->d.dNSName);
+
+                        debug_print("matches_subject_alternative_name: %s\n", dns_name);
+
+                        // Make sure there isn't an embedded NUL character in the DNS name
+                        if (ASN1_STRING_length(current_name->d.dNSName) != strlen(dns_name)) {
+                                result = SSL_HOSTNAME_MALFORMED_CERTIFICATE;
+                                break;
+                        }
+                        else { // Compare expected hostname with the DNS name
+                                if (host_match(hostname, dns_name) == SSL_HOSTNAME_MATCH_FOUND) {
+                                        result = SSL_HOSTNAME_MATCH_FOUND;
+                                        break;
+                                }
+                        }
+                }
+        }
+        sk_GENERAL_NAME_pop_free(san_names, GENERAL_NAME_free);
+
+        return result;
+}
+
+
+/**
+* Validates the server's identity by looking for the expected hostname in the
+* server's certificate. As described in RFC 6125, it first tries to find a match
+* in the Subject Alternative Name extension. If the extension is not present in
+* the certificate, it checks the Common Name instead.
+*
+* Returns MatchFound if a match was found.
+* Returns MatchNotFound if no matches were found.
+* Returns MalformedCertificate if any of the hostnames had a NUL character embedded in it.
+* Returns Error if there was an error.
+*/
+SSLHostnameValidationResult ssl_validate_hostname(const char *hostname, const X509 *server_cert) {
+        SSLHostnameValidationResult result;
+
+        debug_print("ssl_validate_hostname: validating hostname: %s\n", hostname);
+
+        if((hostname == NULL) || (server_cert == NULL))
+                return SSL_HOSTNAME_ERROR;
+
+        // First try the Subject Alternative Names extension
+        result = matches_subject_alternative_name(hostname, server_cert);
+        if (result == SSL_HOSTNAME_NO_SAN_PRESENT) {
+                // Extension was not found: try the Common Name
+                result = matches_common_name(hostname, server_cert);
+        }
+
+        return result;
+}
+
+#endif /* USE_SSL */