From d17ce41e29018176ad43f5228f17ba93cab4a346 Mon Sep 17 00:00:00 2001 From: Julius Werner Date: Thu, 1 Oct 2020 18:25:49 -0700 Subject: cbfs: Port cbfs_load() and cbfs_map() to new API This patch adapts cbfs_load() and cbfs_map() to use the new CBFS API directly, rather than through cbfs_boot_locate(). For cbfs_load() this means that attribute metadata does not need to be read twice. Change-Id: I754cc34b1c1471129e15475aa0f1891e02439a02 Signed-off-by: Julius Werner Reviewed-on: https://review.coreboot.org/c/coreboot/+/39305 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin --- src/commonlib/bsd/cbfs_private.c | 32 ++++++++++++++++++++++ .../bsd/include/commonlib/bsd/cbfs_private.h | 5 ++++ 2 files changed, 37 insertions(+) (limited to 'src/commonlib') diff --git a/src/commonlib/bsd/cbfs_private.c b/src/commonlib/bsd/cbfs_private.c index 035684b91e..7814c4a727 100644 --- a/src/commonlib/bsd/cbfs_private.c +++ b/src/commonlib/bsd/cbfs_private.c @@ -159,3 +159,35 @@ cb_err_t cbfs_lookup(cbfs_dev_t dev, const char *name, union cbfs_mdata *mdata_o }; return cbfs_walk(dev, lookup_walker, &args, metadata_hash, 0); } + +const void *cbfs_find_attr(const union cbfs_mdata *mdata, uint32_t attr_tag, size_t size_check) +{ + uint32_t offset = be32toh(mdata->h.attributes_offset); + uint32_t end = be32toh(mdata->h.offset); + + if (!offset) + return NULL; + + while (offset + sizeof(struct cbfs_file_attribute) <= end) { + const struct cbfs_file_attribute *attr = (const void *)mdata->raw + offset; + const uint32_t tag = be32toh(attr->tag); + const uint32_t len = be32toh(attr->len); + + if (offset + len > end) { + ERROR("Attribute %s[%u] overflows end of metadata\n", + mdata->filename, tag); + return NULL; + } + if (tag == attr_tag) { + if (size_check && len != size_check) { + ERROR("Attribute %s[%u] size mismatch: %u != %zu\n", + mdata->filename, tag, len, size_check); + return NULL; + } + return attr; + } + offset += len; + } + + return NULL; +} diff --git a/src/commonlib/bsd/include/commonlib/bsd/cbfs_private.h b/src/commonlib/bsd/include/commonlib/bsd/cbfs_private.h index 64dcf9f5ba..b72463aba3 100644 --- a/src/commonlib/bsd/include/commonlib/bsd/cbfs_private.h +++ b/src/commonlib/bsd/include/commonlib/bsd/cbfs_private.h @@ -134,4 +134,9 @@ cb_err_t cbfs_mcache_lookup(const void *mcache, size_t mcache_size, const char * /* Returns the amount of bytes actually used by the CBFS metadata cache in |mcache|. */ size_t cbfs_mcache_real_size(const void *mcache, size_t mcache_size); +/* Finds a CBFS attribute in a metadata block. Attribute returned as-is (still big-endian). + If |size| is not 0, will check that it matches the length of the attribute (if found)... + else caller is responsible for checking the |len| field to avoid reading out-of-bounds. */ +const void *cbfs_find_attr(const union cbfs_mdata *mdata, uint32_t attr_tag, size_t size_check); + #endif /* _COMMONLIB_BSD_CBFS_PRIVATE_H_ */ -- cgit v1.2.3