Philippe Mathieu-Daudé <phi...@redhat.com> writes:
> The Edk2Crypto object is used to hold configuration values specific
> to EDK2.
>
> The edk2_add_host_crypto_policy() function loads crypto policies
> from the host, and register them as fw_cfg named file items.
> So far only the 'https' policy is supported.
>
> A usercase example is the 'HTTPS Boof' feature of OVMF [*].
>
> Usage example:
>
> $ qemu-system-x86_64 \
> --object edk2_crypto,id=https,\
> ciphers=/etc/crypto-policies/back-ends/openssl.config,\
> cacerts=/etc/pki/ca-trust/extracted/edk2/cacerts.bin
>
> (On Fedora these files are provided by the ca-certificates and
> crypto-policies packages).
>
> [*]: https://github.com/tianocore/edk2/blob/master/OvmfPkg/README
>
> Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com>
> ---
> v3:
> - '-object' -> '--object' in commit description (Eric)
> - reworded the 'TODO: g_free' comment
> ---
> MAINTAINERS | 8 ++
> hw/Makefile.objs | 1 +
> hw/firmware/Makefile.objs | 1 +
> hw/firmware/uefi_edk2_crypto_policies.c | 177 ++++++++++++++++++++++++
> include/hw/firmware/uefi_edk2.h | 28 ++++
> 5 files changed, 215 insertions(+)
> create mode 100644 hw/firmware/Makefile.objs
> create mode 100644 hw/firmware/uefi_edk2_crypto_policies.c
> create mode 100644 include/hw/firmware/uefi_edk2.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index cf09a4c127..70122b3d0d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2206,6 +2206,14 @@ F: include/hw/i2c/smbus_master.h
> F: include/hw/i2c/smbus_slave.h
> F: include/hw/i2c/smbus_eeprom.h
>
> +EDK2 Firmware
> +M: Laszlo Ersek <ler...@redhat.com>
> +M: Philippe Mathieu-Daudé <phi...@redhat.com>
> +S: Maintained
> +F: docs/interop/firmware.json
> +F: hw/firmware/uefi_edk2_crypto_policies.c
> +F: include/hw/firmware/uefi_edk2.h
> +
> Usermode Emulation
> ------------------
> Overall
> diff --git a/hw/Makefile.objs b/hw/Makefile.objs
> index 82aa7fab8e..2b075aa1e0 100644
> --- a/hw/Makefile.objs
> +++ b/hw/Makefile.objs
> @@ -8,6 +8,7 @@ devices-dirs-$(CONFIG_SOFTMMU) += char/
> devices-dirs-$(CONFIG_SOFTMMU) += cpu/
> devices-dirs-$(CONFIG_SOFTMMU) += display/
> devices-dirs-$(CONFIG_SOFTMMU) += dma/
> +devices-dirs-$(CONFIG_SOFTMMU) += firmware/
> devices-dirs-$(CONFIG_SOFTMMU) += gpio/
> devices-dirs-$(CONFIG_HYPERV) += hyperv/
> devices-dirs-$(CONFIG_I2C) += i2c/
> diff --git a/hw/firmware/Makefile.objs b/hw/firmware/Makefile.objs
> new file mode 100644
> index 0000000000..ea1f6d44df
> --- /dev/null
> +++ b/hw/firmware/Makefile.objs
> @@ -0,0 +1 @@
> +common-obj-y += uefi_edk2_crypto_policies.o
> diff --git a/hw/firmware/uefi_edk2_crypto_policies.c
> b/hw/firmware/uefi_edk2_crypto_policies.c
> new file mode 100644
> index 0000000000..5f88819a50
> --- /dev/null
> +++ b/hw/firmware/uefi_edk2_crypto_policies.c
> @@ -0,0 +1,177 @@
> +/*
> + * UEFI EDK2 Support
> + *
> + * Copyright (c) 2019 Red Hat Inc.
> + *
> + * Author:
> + * Philippe Mathieu-Daudé <phi...@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "qom/object_interfaces.h"
> +#include "hw/firmware/uefi_edk2.h"
> +
> +
> +#define TYPE_EDK2_CRYPTO "edk2_crypto"
> +
> +#define EDK2_CRYPTO_CLASS(klass) \
> + OBJECT_CLASS_CHECK(Edk2CryptoClass, (klass), \
> + TYPE_EDK2_CRYPTO)
> +#define EDK2_CRYPTO_GET_CLASS(obj) \
> + OBJECT_GET_CLASS(Edk2CryptoClass, (obj), \
> + TYPE_EDK2_CRYPTO)
> +#define EDK2_CRYPTO(obj) \
> + INTERFACE_CHECK(Edk2Crypto, (obj), \
> + TYPE_EDK2_CRYPTO)
Uh, should this be OBJECT_CLASS_CHECK()? TYPE_EDK2_CRYPTO is a
TYPE_OBJECT, not a TYPE_INTERFACE...
> +
> +typedef struct Edk2Crypto {
> + Object parent_obj;
> +
> + /*
> + * Path to the acceptable ciphersuites and the preferred order from
> + * the host-side crypto policy.
> + */
> + char *ciphers_path;
> +
> + /* Path to the trusted CA certificates configured on the host side. */
> + char *cacerts_path;
> +} Edk2Crypto;
Bike-shedding: I prefer to call file names file names, and reserve
"path" for search paths. But it's your shed, not mine.
> +
> +typedef struct Edk2CryptoClass {
> + ObjectClass parent_class;
> +} Edk2CryptoClass;
> +
> +
> +static void edk2_crypto_prop_set_ciphers(Object *obj, const char *value,
> + Error **errp G_GNUC_UNUSED)
> +{
> + Edk2Crypto *s = EDK2_CRYPTO(obj);
> +
> + g_free(s->ciphers_path);
> + s->ciphers_path = g_strdup(value);
> +}
> +
> +static char *edk2_crypto_prop_get_ciphers(Object *obj,
> + Error **errp G_GNUC_UNUSED)
> +{
> + Edk2Crypto *s = EDK2_CRYPTO(obj);
> +
> + return g_strdup(s->ciphers_path);
> +}
> +
> +static void edk2_crypto_prop_set_cacerts(Object *obj, const char *value,
> + Error **errp G_GNUC_UNUSED)
> +{
> + Edk2Crypto *s = EDK2_CRYPTO(obj);
> +
> + g_free(s->cacerts_path);
> + s->cacerts_path = g_strdup(value);
> +}
> +
> +static char *edk2_crypto_prop_get_cacerts(Object *obj,
> + Error **errp G_GNUC_UNUSED)
> +{
> + Edk2Crypto *s = EDK2_CRYPTO(obj);
> +
> + return g_strdup(s->cacerts_path);
> +}
> +
> +static void edk2_crypto_finalize(Object *obj)
> +{
> + Edk2Crypto *s = EDK2_CRYPTO(obj);
> +
> + g_free(s->ciphers_path);
> + g_free(s->cacerts_path);
> +}
> +
> +static void edk2_crypto_class_init(ObjectClass *oc, void *data)
> +{
> + object_class_property_add_str(oc, "ciphers",
> + edk2_crypto_prop_get_ciphers,
> + edk2_crypto_prop_set_ciphers,
> + NULL);
> + object_class_property_add_str(oc, "cacerts",
> + edk2_crypto_prop_get_cacerts,
> + edk2_crypto_prop_set_cacerts,
> + NULL);
> +}
> +
> +static const TypeInfo edk2_crypto_info = {
> + .parent = TYPE_OBJECT,
> + .name = TYPE_EDK2_CRYPTO,
> + .instance_size = sizeof(Edk2Crypto),
> + .instance_finalize = edk2_crypto_finalize,
> + .class_size = sizeof(Edk2CryptoClass),
> + .class_init = edk2_crypto_class_init,
> + .interfaces = (InterfaceInfo[]) {
> + { TYPE_USER_CREATABLE },
> + { }
> + }
> +};
> +
> +static void edk2_crypto_register_types(void)
> +{
> + type_register_static(&edk2_crypto_info);
> +}
> +
> +type_init(edk2_crypto_register_types);
> +
> +static Edk2Crypto *edk2_crypto_by_id(const char *edk_crypto_id, Error **errp)
> +{
> + Object *obj;
> + Object *container;
> +
> + container = object_get_objects_root();
> + obj = object_resolve_path_component(container,
> + edk_crypto_id);
> + if (!obj) {
> + error_setg(errp, "Cannot find EDK2 crypto object ID %s",
> + edk_crypto_id);
> + return NULL;
> + }
> +
> + if (!object_dynamic_cast(obj, TYPE_EDK2_CRYPTO)) {
> + error_setg(errp, "Object '%s' is not a EDK2 crypto subclass",
> + edk_crypto_id);
> + return NULL;
> + }
> +
> + return EDK2_CRYPTO(obj);
> +}
> +
> +void edk2_add_host_crypto_policy(FWCfgState *fw_cfg)
> +{
> + Edk2Crypto *s;
> +
> + s = edk2_crypto_by_id("https", NULL);
> + if (!s) {
> + return;
> + }
> +
> + if (s->ciphers_path) {
> + /*
> + * Note:
> + * Unlike with fw_cfg_add_file() where the allocated data has
> + * to be valid for the lifetime of the FwCfg object, there is
> + * no such contract interface with fw_cfg_add_file_from_host().
In my review of PATCH 1, I argue there should be.
> + * It would be easier that the FwCfg object keeps reference of
> + * its allocated memory and releases it when destroy, but it
> + * currently doesn't. Meanwhile we simply add this TODO comment.
> + */
> + fw_cfg_add_file_from_host(fw_cfg, "etc/edk2/https/ciphers",
> + s->ciphers_path, NULL);
> + }
> +
> + if (s->cacerts_path) {
> + /*
> + * TODO: g_free the returned pointer
> + * (see previous comment for ciphers_path in this function).
> + */
Is it even possible to reolve this TODO? Is there any point in time
where we can free the returned pointer without leaving a dangling
pointer in @fw_cfg?
> + fw_cfg_add_file_from_host(fw_cfg, "etc/edk2/https/cacerts",
> + s->cacerts_path, NULL);
> + }
> +}
> diff --git a/include/hw/firmware/uefi_edk2.h b/include/hw/firmware/uefi_edk2.h
> new file mode 100644
> index 0000000000..e0b2fb160a
> --- /dev/null
> +++ b/include/hw/firmware/uefi_edk2.h
> @@ -0,0 +1,28 @@
> +/*
> + * UEFI EDK2 Support
> + *
> + * Copyright (c) 2019 Red Hat Inc.
> + *
> + * Author:
> + * Philippe Mathieu-Daudé <phi...@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#ifndef HW_FIRMWARE_UEFI_EDK2_H
> +#define HW_FIRMWARE_UEFI_EDK2_H
> +
> +#include "hw/nvram/fw_cfg.h"
> +
> +/**
> + * edk2_add_host_crypto_policy:
> + * @s: fw_cfg device being modified
> + *
> + * Add a new named file containing the host crypto policy.
> + *
> + * Currently only the 'https' policy is supported.
> + */
> +void edk2_add_host_crypto_policy(FWCfgState *s);
Out of curiosity, what happens if you call this more than once?
> +
> +#endif /* HW_FIRMWARE_UEFI_EDK2_H */
