From: Wendy Liang <[email protected]> Add get_chksum() implementation to calculate the checksum of the loadable sections of the firmware.
Signed-off-by: Wendy Liang <[email protected]> Signed-off-by: Michal Simek <[email protected]> --- drivers/remoteproc/Kconfig | 1 + drivers/remoteproc/remoteproc_elf_loader.c | 109 +++++++++++++++++++++++++++++ drivers/remoteproc/remoteproc_internal.h | 3 + 3 files changed, 113 insertions(+) diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig index 65f86bc..d832f3b 100644 --- a/drivers/remoteproc/Kconfig +++ b/drivers/remoteproc/Kconfig @@ -7,6 +7,7 @@ config REMOTEPROC select FW_LOADER select VIRTIO select VIRTUALIZATION + select CRYPTO help Support for remote processors (such as DSP coprocessors). These are mainly used on embedded systems. diff --git a/drivers/remoteproc/remoteproc_elf_loader.c b/drivers/remoteproc/remoteproc_elf_loader.c index c523983..f508083 100644 --- a/drivers/remoteproc/remoteproc_elf_loader.c +++ b/drivers/remoteproc/remoteproc_elf_loader.c @@ -29,6 +29,7 @@ #include <linux/firmware.h> #include <linux/remoteproc.h> #include <linux/elf.h> +#include <crypto/hash.h> #include "remoteproc_internal.h" @@ -328,10 +329,118 @@ u32 rproc_elf_get_boot_addr(struct rproc *rproc, const struct firmware *fw) return rproc_da_to_va(rproc, shdr->sh_addr, shdr->sh_size); } +/** + * rproc_elf_get_chksum() - calcuate checksum of the loadable section + * @rproc: the rproc handle + * @fw: the ELF firmware image + * @algo: name of the checksum algorithm + * @chksum: checksum + * @output_size: size of the checksum + * + * This function calculate the checksum of the loadable secitons + * of the specified firmware. + * + * Returns 0 for success, negative value for failure. + */ +static int +rproc_elf_get_chksum(struct rproc *rproc, const struct firmware *fw, + char *algo, u8 *chksum, int output_size) +{ + int ret, i; + struct device *dev = &rproc->dev; + struct crypto_shash *tfm; + struct shash_desc *desc; + int algo_len = 0; + struct elf32_hdr *ehdr; + struct elf32_phdr *phdr; + const u8 *elf_data = fw->data; + + memset(chksum, 0, output_size); + /* If no algo is specified, default it to "sha256" */ + if (!strlen(algo)) + sprintf(algo, "sha256"); + ret = crypto_has_alg(algo, 0, 0); + if (!ret) { + dev_err(dev, "failed to find crypto algo: %s.\n", algo); + return -EINVAL; + } + dev_dbg(dev, "firmware checksum algo: %s.\n", algo); + tfm = crypto_alloc_shash(algo, 0, 0); + if (!tfm) { + dev_err(dev, "failed to allocate shash.\n"); + return -ENOMEM; + } + algo_len = crypto_shash_digestsize(tfm); + if (algo_len > output_size) { + dev_err(dev, + "algo digest size %d is larger expected %d.\n", + algo_len, output_size); + return -EINVAL; + } + desc = kzalloc(sizeof(*desc) + algo_len, GFP_KERNEL); + if (!desc) + return -ENOMEM; + desc->tfm = tfm; + ret = crypto_shash_init(desc); + if (ret) { + dev_err(dev, "failed crypto %s initialization.\n", algo); + return ret; + } + + ehdr = (struct elf32_hdr *)elf_data; + phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff); + + /* go through the available ELF segments */ + for (i = 0; i < ehdr->e_phnum; i++, phdr++) { + u32 memsz = phdr->p_memsz; + u32 filesz = phdr->p_filesz; + u32 offset = phdr->p_offset; + + if (phdr->p_type != PT_LOAD) + continue; + + if (filesz > memsz) { + dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n", + filesz, memsz); + ret = -EINVAL; + break; + } + + if (offset + filesz > fw->size) { + dev_err(dev, "truncated fw: need 0x%x avail 0x%zx\n", + offset + filesz, fw->size); + ret = -EINVAL; + break; + } + + /* put the segment where the remote processor expects it */ + if (phdr->p_filesz) { + ret = crypto_shash_update(desc, + elf_data + offset, filesz); + if (ret) { + dev_err(dev, + "Failed to update fw crypto digest state at offset 0x%x, size 0x%x.\n", + offset, filesz); + return ret; + } + } + + } + ret = crypto_shash_final(desc, chksum); + crypto_free_shash(tfm); + kfree(desc); + if (ret) { + dev_err(dev, "failed to finalize checksum of firmware.\n"); + return ret; + } + return ret; +} + const struct rproc_fw_ops rproc_elf_fw_ops = { .load = rproc_elf_load_segments, .find_rsc_table = rproc_elf_find_rsc_table, .find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table, .sanity_check = rproc_elf_sanity_check, + .get_chksum = rproc_elf_get_chksum, .get_boot_addr = rproc_elf_get_boot_addr }; diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h index 1e9e5b3..f03e07a 100644 --- a/drivers/remoteproc/remoteproc_internal.h +++ b/drivers/remoteproc/remoteproc_internal.h @@ -33,6 +33,7 @@ * expects to find it * @sanity_check: sanity check the fw image * @get_boot_addr: get boot address to entry point specified in firmware + * @get_chksum: get checksum of the loadable sections of the firmware */ struct rproc_fw_ops { struct resource_table *(*find_rsc_table)(struct rproc *rproc, @@ -43,6 +44,8 @@ struct rproc_fw_ops { int (*load)(struct rproc *rproc, const struct firmware *fw); int (*sanity_check)(struct rproc *rproc, const struct firmware *fw); u32 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw); + int (*get_chksum)(struct rproc *rproc, const struct firmware *fw, + char *algo, u8 *chksum, int output_size); }; /* from remoteproc_core.c */ -- 1.9.1
