diff --git a/include/libcamera/internal/utils.h b/include/libcamera/internal/utils.h index 742657bebb28..98d5094eb88d 100644 --- a/include/libcamera/internal/utils.h +++ b/include/libcamera/internal/utils.h @@ -8,9 +8,12 @@ #pragma once #include +#include #include #include +#include + namespace libcamera { namespace utils { @@ -21,6 +24,9 @@ void parseDir(const char *libDir, unsigned int maxDepth, unsigned int addDir(const char *libDir, unsigned int maxDepth, std::function func); +int elfVerifyIdent(Span elf); +Span elfLoadSymbol(Span elf, const char *symbol); + } /* namespace utils */ } /* namespace libcamera */ diff --git a/src/libcamera/ipa_module.cpp b/src/libcamera/ipa_module.cpp index e6ea61e44829..c8559ec8b74c 100644 --- a/src/libcamera/ipa_module.cpp +++ b/src/libcamera/ipa_module.cpp @@ -25,6 +25,7 @@ #include #include "libcamera/internal/pipeline_handler.h" +#include "libcamera/internal/utils.h" /** * \file ipa_module.h @@ -40,153 +41,6 @@ namespace libcamera { LOG_DEFINE_CATEGORY(IPAModule) -namespace { - -template -typename std::remove_extent_t *elfPointer(Span elf, - off_t offset, size_t objSize) -{ - size_t size = offset + objSize; - if (size > elf.size() || size < objSize) - return nullptr; - - return reinterpret_cast *>( - reinterpret_cast(elf.data()) + offset); -} - -template -typename std::remove_extent_t *elfPointer(Span elf, - off_t offset) -{ - return elfPointer(elf, offset, sizeof(T)); -} - -int elfVerifyIdent(Span elf) -{ - const char *e_ident = elfPointer(elf, 0); - if (!e_ident) - return -ENOEXEC; - - if (e_ident[EI_MAG0] != ELFMAG0 || - e_ident[EI_MAG1] != ELFMAG1 || - e_ident[EI_MAG2] != ELFMAG2 || - e_ident[EI_MAG3] != ELFMAG3 || - e_ident[EI_VERSION] != EV_CURRENT) - return -ENOEXEC; - - int bitClass = sizeof(unsigned long) == 4 ? ELFCLASS32 : ELFCLASS64; - if (e_ident[EI_CLASS] != bitClass) - return -ENOEXEC; - - int a = 1; - unsigned char endianness = *reinterpret_cast(&a) == 1 - ? ELFDATA2LSB : ELFDATA2MSB; - if (e_ident[EI_DATA] != endianness) - return -ENOEXEC; - - return 0; -} - -const ElfW(Shdr) *elfSection(Span elf, const ElfW(Ehdr) *eHdr, - ElfW(Half) idx) -{ - if (idx >= eHdr->e_shnum) - return nullptr; - - off_t offset = eHdr->e_shoff + idx * - static_cast(eHdr->e_shentsize); - return elfPointer(elf, offset); -} - -/** - * \brief Retrieve address and size of a symbol from an mmap'ed ELF file - * \param[in] elf Address and size of mmap'ed ELF file - * \param[in] symbol Symbol name - * - * \return The memory region storing the symbol on success, or an empty span - * otherwise - */ -Span elfLoadSymbol(Span elf, const char *symbol) -{ - const ElfW(Ehdr) *eHdr = elfPointer(elf, 0); - if (!eHdr) - return {}; - - const ElfW(Shdr) *sHdr = elfSection(elf, eHdr, eHdr->e_shstrndx); - if (!sHdr) - return {}; - off_t shnameoff = sHdr->sh_offset; - - /* Locate .dynsym section header. */ - const ElfW(Shdr) *dynsym = nullptr; - for (unsigned int i = 0; i < eHdr->e_shnum; i++) { - sHdr = elfSection(elf, eHdr, i); - if (!sHdr) - return {}; - - off_t offset = shnameoff + sHdr->sh_name; - const char *name = elfPointer(elf, offset); - if (!name) - return {}; - - if (sHdr->sh_type == SHT_DYNSYM && !strcmp(name, ".dynsym")) { - dynsym = sHdr; - break; - } - } - - if (dynsym == nullptr) { - LOG(IPAModule, Error) << "ELF has no .dynsym section"; - return {}; - } - - sHdr = elfSection(elf, eHdr, dynsym->sh_link); - if (!sHdr) - return {}; - off_t dynsym_nameoff = sHdr->sh_offset; - - /* Locate symbol in the .dynsym section. */ - const ElfW(Sym) *targetSymbol = nullptr; - unsigned int dynsym_num = dynsym->sh_size / dynsym->sh_entsize; - for (unsigned int i = 0; i < dynsym_num; i++) { - off_t offset = dynsym->sh_offset + dynsym->sh_entsize * i; - const ElfW(Sym) *sym = elfPointer(elf, offset); - if (!sym) - return {}; - - offset = dynsym_nameoff + sym->st_name; - const char *name = elfPointer(elf, offset, - strlen(symbol) + 1); - if (!name) - return {}; - - if (!strcmp(name, symbol) && - sym->st_info & STB_GLOBAL) { - targetSymbol = sym; - break; - } - } - - if (targetSymbol == nullptr) { - LOG(IPAModule, Error) << "Symbol " << symbol << " not found"; - return {}; - } - - /* Locate and return data of symbol. */ - sHdr = elfSection(elf, eHdr, targetSymbol->st_shndx); - if (!sHdr) - return {}; - off_t offset = sHdr->sh_offset + (targetSymbol->st_value - sHdr->sh_addr); - const uint8_t *data = elfPointer(elf, offset, - targetSymbol->st_size); - if (!data) - return {}; - - return { data, targetSymbol->st_size }; -} - -} /* namespace */ - /** * \def IPA_MODULE_API_VERSION * \brief The IPA module API version @@ -280,13 +134,13 @@ int IPAModule::loadIPAModuleInfo() } Span data = file.map(); - int ret = elfVerifyIdent(data); + int ret = utils::elfVerifyIdent(data); if (ret) { LOG(IPAModule, Error) << "IPA module is not an ELF file"; return ret; } - Span info = elfLoadSymbol(data, "ipaModuleInfo"); + Span info = utils::elfLoadSymbol(data, "ipaModuleInfo"); if (info.size() < sizeof(info_)) { LOG(IPAModule, Error) << "IPA module has no valid info"; return -EINVAL; diff --git a/src/libcamera/utils.cpp b/src/libcamera/utils.cpp index ef046ac3134e..f7bc5c54ff57 100644 --- a/src/libcamera/utils.cpp +++ b/src/libcamera/utils.cpp @@ -10,20 +10,63 @@ #include #include #include +#include +#include #include #include #include #include +#include + /** * \file internal/utils.h * \brief Miscellaneous utility functions (internal) */ +/* musl doesn't declare _DYNAMIC in link.h, declare it manually. */ +extern ElfW(Dyn) _DYNAMIC[]; + namespace libcamera { +namespace { + +template +typename std::remove_extent_t *elfPointer(Span elf, + off_t offset, size_t objSize) +{ + size_t size = offset + objSize; + if (size > elf.size() || size < objSize) + return nullptr; + + return reinterpret_cast *>( + reinterpret_cast(elf.data()) + offset); +} + +template +typename std::remove_extent_t *elfPointer(Span elf, + off_t offset) +{ + return elfPointer(elf, offset, sizeof(T)); +} + +const ElfW(Shdr) *elfSection(Span elf, const ElfW(Ehdr) *eHdr, + ElfW(Half) idx) +{ + if (idx >= eHdr->e_shnum) + return nullptr; + + off_t offset = eHdr->e_shoff + idx * + static_cast(eHdr->e_shentsize); + return elfPointer(elf, offset); +} + +} /* namespace */ + namespace utils { +LOG_DEFINE_CATEGORY(Utils) + /** * \brief Identify shared library objects within a directory * \param[in] libDir The directory to search for shared objects @@ -102,6 +145,120 @@ unsigned int addDir(const char *libDir, unsigned int maxDepth, return count; } +int elfVerifyIdent(Span elf) +{ + const char *e_ident = elfPointer(elf, 0); + if (!e_ident) + return -ENOEXEC; + + if (e_ident[EI_MAG0] != ELFMAG0 || + e_ident[EI_MAG1] != ELFMAG1 || + e_ident[EI_MAG2] != ELFMAG2 || + e_ident[EI_MAG3] != ELFMAG3 || + e_ident[EI_VERSION] != EV_CURRENT) + return -ENOEXEC; + + int bitClass = sizeof(unsigned long) == 4 ? ELFCLASS32 : ELFCLASS64; + if (e_ident[EI_CLASS] != bitClass) + return -ENOEXEC; + + int a = 1; + unsigned char endianness = *reinterpret_cast(&a) == 1 + ? ELFDATA2LSB : ELFDATA2MSB; + if (e_ident[EI_DATA] != endianness) + return -ENOEXEC; + + return 0; +} + +/** + * \brief Retrieve address and size of a symbol from an mmap'ed ELF file + * \param[in] elf Address and size of mmap'ed ELF file + * \param[in] symbol Symbol name + * + * \return The memory region storing the symbol on success, or an empty span + * otherwise + */ +Span elfLoadSymbol(Span elf, const char *symbol) +{ + const ElfW(Ehdr) *eHdr = elfPointer(elf, 0); + if (!eHdr) + return {}; + + const ElfW(Shdr) *sHdr = elfSection(elf, eHdr, eHdr->e_shstrndx); + if (!sHdr) + return {}; + off_t shnameoff = sHdr->sh_offset; + + /* Locate .dynsym section header. */ + const ElfW(Shdr) *dynsym = nullptr; + for (unsigned int i = 0; i < eHdr->e_shnum; i++) { + sHdr = elfSection(elf, eHdr, i); + if (!sHdr) + return {}; + + off_t offset = shnameoff + sHdr->sh_name; + const char *name = elfPointer(elf, offset); + if (!name) + return {}; + + if (sHdr->sh_type == SHT_DYNSYM && !strcmp(name, ".dynsym")) { + dynsym = sHdr; + break; + } + } + + if (dynsym == nullptr) { + LOG(Utils, Error) << "ELF has no .dynsym section"; + return {}; + } + + sHdr = elfSection(elf, eHdr, dynsym->sh_link); + if (!sHdr) + return {}; + off_t dynsym_nameoff = sHdr->sh_offset; + + /* Locate symbol in the .dynsym section. */ + const ElfW(Sym) *targetSymbol = nullptr; + unsigned int dynsym_num = dynsym->sh_size / dynsym->sh_entsize; + for (unsigned int i = 0; i < dynsym_num; i++) { + off_t offset = dynsym->sh_offset + dynsym->sh_entsize * i; + const ElfW(Sym) *sym = elfPointer(elf, offset); + if (!sym) + return {}; + + offset = dynsym_nameoff + sym->st_name; + const char *name = elfPointer(elf, offset, + strlen(symbol) + 1); + if (!name) + return {}; + + if (!strcmp(name, symbol) && + sym->st_info & STB_GLOBAL) { + targetSymbol = sym; + break; + } + } + + if (targetSymbol == nullptr) { + LOG(Utils, Error) << "Symbol " << symbol << " not found"; + return {}; + } + + /* Locate and return data of symbol. */ + sHdr = elfSection(elf, eHdr, targetSymbol->st_shndx); + if (!sHdr) + return {}; + off_t offset = sHdr->sh_offset + (targetSymbol->st_value - sHdr->sh_addr); + const uint8_t *data = elfPointer(elf, offset, + targetSymbol->st_size); + if (!data) + return {}; + + return { data, targetSymbol->st_size }; +} + + } /* namespace utils */ } /* namespace libcamera */