usermode capable kernel with logging syscall

1 files changed, 47 insertions, 0 deletions

diff --git a/arch/x86_64/elf.c b/arch/x86_64/elf.c
new file mode 100644
index 0000000..60b8f13
--- /dev/null
+++ b/arch/x86_64/elf.c
@@ -0,0 +1,47 @@
+#include "elf.h"
+#include "lib/string.h"
+#include "usr/elf.h"
+#include "io/log.h"
+#include "mem/memory.h"
+
+void*
+elf_load(const void *data, size_t len)
+{
+    if(data == NULL) return NULL;
+    if(len < 4) return NULL;
+
+    struct ELF_header *ehdr = (struct ELF_header*)data;
+    if(ehdr->e_ident[EI_MAG0] != E_IDENT_MAG0 &&
+            ehdr->e_ident[EI_MAG1] != E_IDENT_MAG1 &&
+            ehdr->e_ident[EI_MAG2] != E_IDENT_MAG2 &&
+            ehdr->e_ident[EI_MAG3] != E_IDENT_MAG3)
+        return NULL;
+
+    if(ehdr->e_ident[EI_CLASS] != E_IDENT_CLASS64) {
+        klogf("Jove does not support ELF files of class CLASS32\n");
+        return NULL;
+    }
+
+    if(ehdr->e_type != ET_EXEC) {
+        klogf("Jove does not support ELF files other than ET_EXEC\n");
+        return NULL;
+    }
+
+    uint64_t entry = ehdr->e_entry;
+    
+    size_t phdrc = ehdr->e_phnum;
+    struct ELF_phdr *phdrs = (struct ELF_phdr*)((uintptr_t)data + ehdr->e_phoff);
+    
+    for(size_t phdri = 0; phdri < phdrc; phdri++)
+    {
+        struct ELF_phdr *phdr = &phdrs[phdri];
+        void *pdata = (void*)phdr->p_vaddr;
+            
+        mem_ensure_range(phdr->p_vaddr, phdr->p_vaddr + phdr->p_memsz, true, true);
+        if(phdr->p_type == PT_LOAD)
+        {
+            memcpy(pdata, (void*)((uintptr_t)data + phdr->p_offset), phdr->p_filesz);
+        }
+    }
+    return (void*)entry;
+}