diff options
Diffstat (limited to 'pk/elf.c')
-rw-r--r-- | pk/elf.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/pk/elf.c b/pk/elf.c new file mode 100644 index 0000000..51debb3 --- /dev/null +++ b/pk/elf.c @@ -0,0 +1,57 @@ +#include <sys/stat.h> +#include <fcntl.h> +#include <elf.h> +#include <string.h> +#include "file.h" +#include "pk.h" + +long load_elf(const char* fn, int* user64) +{ + sysret_t ret = file_open(fn, strlen(fn)+1, O_RDONLY, 0); + file_t* file = (file_t*)ret.result; + if(file == NULL) + panic("couldn't open %s!", fn); + + char buf[2048]; // XXX + int header_size = file_read(file, buf, sizeof(buf)).result; + kassert(header_size >= (int)sizeof(Elf64_Ehdr)); + + const Elf64_Ehdr* eh64 = (const Elf64_Ehdr*)buf; + kassert(eh64->e_ident[0] == '\177' && eh64->e_ident[1] == 'E' && + eh64->e_ident[2] == 'L' && eh64->e_ident[3] == 'F'); + + #define LOAD_ELF do { \ + eh = (typeof(eh))buf; \ + kassert(header_size >= eh->e_phoff + eh->e_phnum*sizeof(*ph)); \ + ph = (typeof(ph))(buf+eh->e_phoff); \ + for(int i = 0; i < eh->e_phnum; i++, ph++) { \ + if(ph->p_type == SHT_PROGBITS && ph->p_memsz) { \ + kassert(file_pread(file, (char*)(long)ph->p_vaddr, ph->p_filesz, ph->p_offset).result == ph->p_filesz); \ + memset((char*)(long)ph->p_vaddr+ph->p_filesz, 0, ph->p_memsz-ph->p_filesz); \ + } \ + } \ + } while(0) + + long entry; + if(eh64->e_ident[EI_CLASS] == ELFCLASS32) + { + Elf32_Ehdr* eh; + Elf32_Phdr* ph; + LOAD_ELF; + entry = eh->e_entry; + } + else + { + kassert(eh64->e_ident[EI_CLASS] == ELFCLASS64); + Elf64_Ehdr* eh; + Elf64_Phdr* ph; + LOAD_ELF; + entry = eh->e_entry; + } + + *user64 = eh64->e_ident[EI_CLASS] == ELFCLASS64; + + file_decref(file); + + return entry; +} |