diff --git a/docs/tools/qemu-nbd.rst b/docs/tools/qemu-nbd.rst index 6031f96893..2b8c90c354 100644 --- a/docs/tools/qemu-nbd.rst +++ b/docs/tools/qemu-nbd.rst @@ -169,6 +169,19 @@ driver options if ``--image-opts`` is specified. option; or provide the credentials needed for connecting as a client in list mode. +.. option:: --tls-hostname=hostname + + When validating an x509 certificate received over a TLS connection, + the hostname that the NBD client used to connect will be checked + against information in the server provided certificate. Sometimes + it might be required to override the hostname used to perform this + check. For example, if the NBD client is using a tunnel from localhost + to connect to the remote server, the `--tls-hostname` option should + be used to set the officially expected hostname of the remote NBD + server. This can also be used if accessing NBD over a UNIX socket + where there is no inherent hostname available. This is only permitted + when acting as a NBD client with the `--list` option. + .. option:: --fork Fork off the server process and exit the parent once the server is running. diff --git a/qemu-nbd.c b/qemu-nbd.c index c6c20df68a..18d281aba3 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -69,6 +69,7 @@ #define QEMU_NBD_OPT_TLSAUTHZ 264 #define QEMU_NBD_OPT_PID_FILE 265 #define QEMU_NBD_OPT_SELINUX_LABEL 266 +#define QEMU_NBD_OPT_TLSHOSTNAME 267 #define MBR_SIZE 512 @@ -542,6 +543,7 @@ int main(int argc, char **argv) { "export-name", required_argument, NULL, 'x' }, { "description", required_argument, NULL, 'D' }, { "tls-creds", required_argument, NULL, QEMU_NBD_OPT_TLSCREDS }, + { "tls-hostname", required_argument, NULL, QEMU_NBD_OPT_TLSHOSTNAME }, { "tls-authz", required_argument, NULL, QEMU_NBD_OPT_TLSAUTHZ }, { "image-opts", no_argument, NULL, QEMU_NBD_OPT_IMAGE_OPTS }, { "trace", required_argument, NULL, 'T' }, @@ -568,6 +570,7 @@ int main(int argc, char **argv) strList *bitmaps = NULL; bool alloc_depth = false; const char *tlscredsid = NULL; + const char *tlshostname = NULL; bool imageOpts = false; bool writethrough = false; /* Client will flush as needed. */ bool fork_process = false; @@ -747,6 +750,9 @@ int main(int argc, char **argv) case QEMU_NBD_OPT_TLSCREDS: tlscredsid = optarg; break; + case QEMU_NBD_OPT_TLSHOSTNAME: + tlshostname = optarg; + break; case QEMU_NBD_OPT_IMAGE_OPTS: imageOpts = true; break; @@ -835,6 +841,10 @@ int main(int argc, char **argv) error_report("TLS authorization is incompatible with export list"); exit(EXIT_FAILURE); } + if (tlshostname && !list) { + error_report("TLS hostname is only supported with export list"); + exit(EXIT_FAILURE); + } tlscreds = nbd_get_tls_creds(tlscredsid, list, &local_err); if (local_err) { error_reportf_err(local_err, "Failed to get TLS creds: "); @@ -845,6 +855,10 @@ int main(int argc, char **argv) error_report("--tls-authz is not permitted without --tls-creds"); exit(EXIT_FAILURE); } + if (tlshostname) { + error_report("--tls-hostname is not permitted without --tls-creds"); + exit(EXIT_FAILURE); + } } if (selinux_label) { @@ -861,7 +875,8 @@ int main(int argc, char **argv) if (list) { saddr = nbd_build_socket_address(sockpath, bindto, port); - return qemu_nbd_client_list(saddr, tlscreds, bindto); + return qemu_nbd_client_list(saddr, tlscreds, + tlshostname ? tlshostname : bindto); } #if !HAVE_NBD_DEVICE