On 11/26/22 11:59, Safae Ouajih wrote:
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>
> This adds support for libxbc used to support Bootconfig feature.
> Bootconfig documentation : [1]
> This was imported from [2], commit [3]
This should be written something like
This was adapted from downstream [2] commit 7af0a0506d4 ("shortlog
summary").
>
> [1]
> https://source.android.com/docs/core/architecture/bootloader/implementing-bootconfig
> [2] https://android.googlesource.com/platform/external/u-boot/
> [3] `7af0a0506d4de6f5ea147d10fb0664a8af07d326`
>
> Signed-off-by: Safae Ouajih <soua...@baylibre.com>
> ---
> include/xbc.h | 1 +
> lib/Kconfig | 12 +++++
> lib/Makefile | 1 +
> lib/libxbc/Makefile | 1 +
> lib/libxbc/libxbc.c | 112 ++++++++++++++++++++++++++++++++++++++++++++
> lib/libxbc/libxbc.h | 54 +++++++++++++++++++++
> 6 files changed, 181 insertions(+)
> create mode 100644 include/xbc.h
> create mode 100644 lib/libxbc/Makefile
> create mode 100644 lib/libxbc/libxbc.c
> create mode 100644 lib/libxbc/libxbc.h
I understand that you may want to import this "library" directly, but it
is really so short that I question the virtue of this. I think it would
be better to convert this to U-Boot style.
--Sean
> diff --git a/include/xbc.h b/include/xbc.h
> new file mode 100644
> index 000000000000..725e65ff6ad8
> --- /dev/null
> +++ b/include/xbc.h
> @@ -0,0 +1 @@
> +#include <../lib/libxbc/libxbc.h>
> diff --git a/lib/Kconfig b/lib/Kconfig
> index 6abe1d0a863b..eca752b7db79 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -417,6 +417,18 @@ config LIBAVB
>
> endmenu
>
> +menu "Android Boot Configuration"
> +config LIBXBC
> + bool "Android Boot Configuration support"
> + depends on ANDROID_BOOT_IMAGE
> + default n
> + help
> + This enables support of Boot Configuration which can be used
> + to pass boot configuration parameters to user space. These
> + parameters will show up in /proc/bootconfig similar to the kernel
> + parameters that show up in /proc/cmdline
> +endmenu
> +
> menu "Hashing Support"
>
> config BLAKE2
> diff --git a/lib/Makefile b/lib/Makefile
> index f2cfd1e42892..b0ad522ac116 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -87,6 +87,7 @@ obj-$(CONFIG_$(SPL_)LZ4) += lz4_wrapper.o
> obj-$(CONFIG_$(SPL_)LIB_RATIONAL) += rational.o
>
> obj-$(CONFIG_LIBAVB) += libavb/
> +obj-$(CONFIG_LIBXBC) += libxbc/
>
> obj-$(CONFIG_$(SPL_TPL_)OF_LIBFDT) += libfdt/
> obj-$(CONFIG_$(SPL_TPL_)OF_REAL) += fdtdec_common.o fdtdec.o
> diff --git a/lib/libxbc/Makefile b/lib/libxbc/Makefile
> new file mode 100644
> index 000000000000..7ac4cde05666
> --- /dev/null
> +++ b/lib/libxbc/Makefile
> @@ -0,0 +1 @@
> +obj-$(CONFIG_LIBXBC) += libxbc.o
> diff --git a/lib/libxbc/libxbc.c b/lib/libxbc/libxbc.c
> new file mode 100644
> index 000000000000..129bffc7c628
> --- /dev/null
> +++ b/lib/libxbc/libxbc.c
> @@ -0,0 +1,112 @@
> +/*
> + * Copyright (C) 2021 The Android Open Source Project
> + *
> + * Licensed under the Apache License, Version 2.0 (the "License");
> + * you may not use this file except in compliance with the License.
> + * You may obtain a copy of the License at
> + *
> + * http://www.apache.org/licenses/LICENSE-2.0
> + *
> + * Unless required by applicable law or agreed to in writing, software
> + * distributed under the License is distributed on an "AS IS" BASIS,
> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
> + * See the License for the specific language governing permissions and
> + * limitations under the License.
> + */
> +#include "libxbc.h"
> +#define BOOTCONFIG_MAGIC "#BOOTCONFIG\n"
> +#define BOOTCONFIG_MAGIC_SIZE 12
> +#define BOOTCONFIG_SIZE_SIZE 4
> +#define BOOTCONFIG_CHECKSUM_SIZE 4
> +#define BOOTCONFIG_TRAILER_SIZE BOOTCONFIG_MAGIC_SIZE + \
> + BOOTCONFIG_SIZE_SIZE + \
> + BOOTCONFIG_CHECKSUM_SIZE
> +
> +/*
> + * Simple checksum for a buffer.
> + *
> + * @param addr pointer to the start of the buffer.
> + * @param size size of the buffer in bytes.
> + * @return check sum result.
> + */
> +static uint32_t checksum(const unsigned char* const buffer, uint32_t size) {
> + uint32_t sum = 0;
> + for (uint32_t i = 0; i < size; i++) {
> + sum += buffer[i];
> + }
> + return sum;
> +}
> +
> +/*
> + * Check if the bootconfig trailer is present within the bootconfig section.
> + *
> + * @param bootconfig_end_addr address of the end of the bootconfig section.
> If
> + * the trailer is present, it will be directly preceding this address.
> + * @return true if the trailer is present, false if not.
> + */
> +static bool isTrailerPresent(uint64_t bootconfig_end_addr) {
> + return !strncmp((char*)(bootconfig_end_addr - BOOTCONFIG_MAGIC_SIZE),
> + BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_SIZE);
> +}
> +
> +/*
> + * Add a string of boot config parameters to memory appended by the trailer.
> + */
> +int32_t addBootConfigParameters(char* params, uint32_t params_size,
> + uint64_t bootconfig_start_addr, uint32_t bootconfig_size) {
> + if (!params || !bootconfig_start_addr) {
> + return -1;
> + }
> + if (params_size == 0) {
> + return 0;
> + }
> + int32_t applied_bytes = 0;
> + int32_t new_size = 0;
> + uint64_t end = bootconfig_start_addr + bootconfig_size;
> + if (isTrailerPresent(end)) {
> + end -= BOOTCONFIG_TRAILER_SIZE;
> + applied_bytes -= BOOTCONFIG_TRAILER_SIZE;
> + memcpy(&new_size, (void *)end, BOOTCONFIG_SIZE_SIZE);
> + } else {
> + new_size = bootconfig_size;
> + }
> + // params
> + memcpy((void*)end, params, params_size);
> + applied_bytes += params_size;
> + applied_bytes += addBootConfigTrailer(bootconfig_start_addr,
> + bootconfig_size + applied_bytes);
> + return applied_bytes;
> +}
> +
> +/*
> + * Add boot config trailer.
> + */
> +
> +int32_t addBootConfigTrailer(uint64_t bootconfig_start_addr,
> + uint32_t bootconfig_size) {
> + if (!bootconfig_start_addr) {
> + return -1;
> + }
> +
> + if (bootconfig_size == 0) {
> + return 0;
> + }
> +
> + uint64_t end = bootconfig_start_addr + bootconfig_size;
> + if (isTrailerPresent(end)) {
> + return 0;
> + }
> +
> + // size
> + memcpy((void *)(end), &bootconfig_size, BOOTCONFIG_SIZE_SIZE);
> +
> + // checksum
> + uint32_t sum = checksum((unsigned char*)bootconfig_start_addr,
> bootconfig_size);
> + memcpy((void *)(end + BOOTCONFIG_SIZE_SIZE), &sum,
> BOOTCONFIG_CHECKSUM_SIZE);
> +
> + // magic
> + memcpy((void *)(end + BOOTCONFIG_SIZE_SIZE + BOOTCONFIG_CHECKSUM_SIZE),
> + BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_SIZE);
> +
> + return BOOTCONFIG_TRAILER_SIZE;
> +}
> diff --git a/lib/libxbc/libxbc.h b/lib/libxbc/libxbc.h
> new file mode 100644
> index 000000000000..0b6ba4960905
> --- /dev/null
> +++ b/lib/libxbc/libxbc.h
> @@ -0,0 +1,54 @@
> +/*
> + * Copyright (C) 2021 The Android Open Source Project
> + *
> + * Licensed under the Apache License, Version 2.0 (the "License");
> + * you may not use this file except in compliance with the License.
> + * You may obtain a copy of the License at
> + *
> + * http://www.apache.org/licenses/LICENSE-2.0
> + *
> + * Unless required by applicable law or agreed to in writing, software
> + * distributed under the License is distributed on an "AS IS" BASIS,
> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
> + * See the License for the specific language governing permissions and
> + * limitations under the License.
> + */
> +#ifndef LIBXBC_H_
> +#define LIBXBC_H_
> +
> +#include <common.h>
> +/*
> + * Add a string of boot config parameters to memory appended by the trailer.
> + * This memory needs to be immediately following the end of the ramdisks.
> + * The new boot config trailer will be written to the end of the entire
> + * parameter section(previous + new). The trailer contains a 4 byte size of
> the
> + * parameters, followed by a 4 byte checksum of the parameters, followed by
> a 12
> + * byte magic string.
> + *
> + * @param params pointer to string of boot config parameters
> + * @param params_size size of params string in bytes
> + * @param bootconfig_start_addr address that the boot config section is
> starting
> + * at in memory.
> + * @param bootconfig_size size of the current bootconfig section in bytes.
> + * @return number of bytes added to the boot config section. -1 for error.
> + */
> +int addBootConfigParameters(char *params, uint32_t params_size,
> + uint64_t bootconfig_start_addr,
> + uint32_t bootconfig_size);
> +/*
> + * Add the boot config trailer to the end of the boot config parameter
> section.
> + * This can be used after the vendor bootconfig section has been placed into
> + * memory if there are no additional parameters that need to be added.
> + * The new boot config trailer will be written to the end of the entire
> + * parameter section at (bootconfig_start_addr + bootconfig_size).
> + * The trailer contains a 4 byte size of the parameters, followed by a 4 byte
> + * checksum of the parameters, followed by a 12 byte magic string.
> + *
> + * @param bootconfig_start_addr address that the boot config section is
> starting
> + * at in memory.
> + * @param bootconfig_size size of the current bootconfig section in bytes.
> + * @return number of bytes added to the boot config section. -1 for error.
> + */
> +int addBootConfigTrailer(uint64_t bootconfig_start_addr,
> + uint32_t bootconfig_size);
> +#endif /* LIBXBC_H_ */
> --
> 2.25.1
>
