lib-ssl-iostream: Support IP address SANs

diff --git a/src/lib-ssl-iostream/iostream-openssl-common.c b/src/lib-ssl-iostream/iostream-openssl-common.c
index d88b2ad4e48316021cafb2770ce598814b724580..bc0180367e17c94aa30062329131f1249e9331c8 100644 (file)
--- a/src/lib-ssl-iostream/iostream-openssl-common.c
+++ b/src/lib-ssl-iostream/iostream-openssl-common.c
@@ -1,11 +1,13 @@
 /* Copyright (c) 2009-2017 Dovecot authors, see the included COPYING file */
 
 #include "lib.h"
+#include "net.h"
 #include "str.h"
 #include "iostream-openssl.h"
 
 #include <openssl/x509v3.h>
 #include <openssl/err.h>
+#include <arpa/inet.h>
 
 enum {
        DOVECOT_SSL_PROTO_SSLv2         = 0x01,
@@ -101,6 +103,23 @@ static const char *get_general_dns_name(const GENERAL_NAME *name)
        return asn1_string_to_c(name->d.ia5);
 }
 
+static int get_general_ip_addr(const GENERAL_NAME *name, struct ip_addr *ip_r)
+{
+       if (ASN1_STRING_type(name->d.ip) != V_ASN1_OCTET_STRING)
+               return 0;
+       const unsigned char *data = ASN1_STRING_get0_data(name->d.ip);
+
+       if (name->d.ip->length == sizeof(ip_r->u.ip4.s_addr)) {
+               ip_r->family = AF_INET;
+               memcpy(&ip_r->u.ip4.s_addr, data, sizeof(ip_r->u.ip4.s_addr));
+       } else if (name->d.ip->length == sizeof(ip_r->u.ip6.s6_addr)) {
+               ip_r->family = AF_INET6;
+               memcpy(ip_r->u.ip6.s6_addr, data, sizeof(ip_r->u.ip6.s6_addr));
+       } else
+               return -1;
+       return 0;
+}
+
 static const char *get_cname(X509 *cert)
 {
        X509_NAME *name;
@@ -140,6 +159,7 @@ int openssl_cert_match_name(SSL *ssl, const char *verify_name)
        X509 *cert;
        STACK_OF(GENERAL_NAME) *gnames;
        const GENERAL_NAME *gn;
+       struct ip_addr ip;
        const char *dnsname;
        bool dns_names = FALSE;
        unsigned int i, count;
@@ -151,13 +171,31 @@ int openssl_cert_match_name(SSL *ssl, const char *verify_name)
        /* verify against SubjectAltNames */
        gnames = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
        count = gnames == NULL ? 0 : sk_GENERAL_NAME_num(gnames);
+
+       i_zero(&ip);
+       /* try to convert verify_name to IP */
+       if (inet_pton(AF_INET6, verify_name, &ip.u.ip6) == 1)
+               ip.family = AF_INET6;
+       else if (inet_pton(AF_INET, verify_name, &ip.u.ip4) == 1)
+               ip.family = AF_INET;
+       else
+               i_zero(&ip);
+
        for (i = 0; i < count; i++) {
                gn = sk_GENERAL_NAME_value(gnames, i);
+
                if (gn->type == GEN_DNS) {
                        dns_names = TRUE;
                        dnsname = get_general_dns_name(gn);
                        if (openssl_hostname_equals(dnsname, verify_name))
                                break;
+               } else if (gn->type == GEN_IPADD) {
+                       struct ip_addr ip_2;
+                       i_zero(&ip_2);
+                       dns_names = TRUE;
+                       if (get_general_ip_addr(gn, &ip_2) == 0 &&
+                           net_ip_compare(&ip, &ip_2))
+                               break;
                }
        }
        sk_GENERAL_NAME_pop_free(gnames, GENERAL_NAME_free);