dynamic linking effectively working, no dependency loading

Makefile

@@ -65,7 +65,7 @@ image:	all
 	@ cp bin/* boot/bin
 	@ cp lib/dl.so boot/lib
 	@ cp lib/libc.so boot/lib
-	@ cp lib/libtest.so boot/lib
+	@ cp lib/librdi.so boot/lib
 	@ cp sbin/* boot/sbin
 #	@ cp -r etc/* boot/etc
 

daemon/init/Makefile

@@ -4,7 +4,7 @@ SOURCES += $(BUILDDIR)/lib/c0.o
 SUBDIR	:= daemon/init
 TARGET	:= init
 CFLAGS  += -I$(BUILDDIR)/$(SUBDIR)/inc
-LDFLAGS += -lrdi -lc -static
+LDFLAGS += -static -lrdi -lc
 ASFLAGS := -felf
 
 all: $(TARGET)

daemon/init/main.c

@@ -59,6 +59,12 @@ int main() {
 	/* Boot Image */
 	boot_image = tar_parse((void*) BOOT_IMAGE);
 
+	/* Load shared libraries for drivers */
+	file = tar_find(boot_image, "lib/libc.so");
+	dlload(file->start, file->size, 0);
+	file = tar_find(boot_image, "lib/librdi.so");
+	dlload(file->start, file->size, 0);
+
 	/* Initial Root Filesystem / Device Filesystem / System Filesystem (tmpfs) */
 	argv[0] = "tmpfs";
 	argv[1] = NULL;

dl/Makefile

@@ -3,7 +3,7 @@ SOURCES += $(patsubst %.s,%.o,$(shell find . -name "*.s"))
 SUBDIR	:= dl
 HEADERS := $(shell find . -name "*.h")
 TARGET	:= dl.so
-LDFLAGS	:= -T$(BUILDDIR)/$(SUBDIR)/link.ld
+LDFLAGS	:= -T$(BUILDDIR)/$(SUBDIR)/link.ld -static
 ASFLAGS := -felf
 
 all: $(TARGET)

dl/dl.h

@@ -70,12 +70,14 @@ struct elf_cache {
 	const uint32_t          *pltgot;
 };
 
-void elf_gencache(struct elf_cache *cache, const struct elf32_ehdr *image);
-
-uint32_t elfc_resolve      (struct elf_cache *cache, const char *symbol);
-uint32_t elfc_relocate     (struct elf_cache *cache, const struct elf32_rel *rel);
-void     elfc_relocate_all (struct elf_cache *cache);
-void     elfc_relocate_exec(struct elf_cache *cache);
+void elf_gencache     (struct elf_cache *cache, const struct elf32_ehdr *image);
+void elf_gencache_exec(struct elf_cache *cache, const struct elf32_ehdr *image);
+
+uint32_t elfc_resolve          (struct elf_cache *cache, const char *symbol);
+uint32_t elfc_relocate         (struct elf_cache *cache, const struct elf32_rel *rel);
+void     elfc_relocate_all     (struct elf_cache *cache);
+uint32_t elfc_relocate_exec    (struct elf_cache *cache, const struct elf32_rel *rel);
+void     elfc_relocate_all_exec(struct elf_cache *cache);
 
 int dl_enter(void *entry_ptr);
 

dl/elf.c

@@ -55,8 +55,24 @@ static void _elf_load_phdr(const struct elf32_ehdr *file, uintptr_t base, const
 		else {
 			/* is a read-only data/code segment */
 
-			/* move memory */
-			page_self((void*) seg_base, dst, phdr->p_filesz);
+			if ((uint32_t) seg_base % PAGESZ) {
+				/* image not page-aligned; copy */
+
+				/* allocate memory */
+				page_anon(dst, phdr->p_memsz, PROT_READ | PROT_WRITE);
+
+				/* copy data */
+				memcpy(dst, seg_base, phdr->p_filesz);
+
+				/* clear rest of segment */
+				memclr(&dst[phdr->p_filesz], phdr->p_memsz - phdr->p_filesz);
+			}
+			else {
+				/* image page-aligned; page flip */
+
+				/* move memory */
+				page_self((void*) seg_base, dst, phdr->p_filesz);
+			}
 		}
 
 		/* set proper permissions */

dl/elfc.c

@@ -70,6 +70,49 @@ uint32_t elfc_relocate(struct elf_cache *cache, const struct elf32_rel *rel) {
 	return symbol_value;
 }
 
+uint32_t elfc_relocate_exec(struct elf_cache *cache, const struct elf32_rel *rel) {
+	const struct elf32_sym *symbol = NULL;
+	uint32_t *image32 = (void*) 0;
+	uint32_t symbol_value;
+
+	/* compute symbol value if needed */
+	switch (ELF32_R_TYPE(rel->r_info)) {
+	case R_386_GLOB_DAT:
+	case R_386_JMP_SLOT:
+	case R_386_32:
+		symbol = &cache->symtab[ELF32_R_SYM(rel->r_info)];
+
+		if (symbol->st_value) {
+			symbol_value = symbol->st_value;
+		}
+		else {
+			symbol_value = elfc_resolve(cache, &cache->strtab[symbol->st_name]);
+		}
+		break;
+	default:
+		symbol_value = 0;
+	}
+
+	/* perform relocation */
+	switch (ELF32_R_TYPE(rel->r_info)) {
+	case R_386_NONE:
+	case R_386_RELATIVE:
+		break;
+		break;
+	case R_386_GLOB_DAT:
+	case R_386_JMP_SLOT:
+		image32[rel->r_offset / 4] = symbol_value;
+		break;
+	case R_386_32:
+		image32[rel->r_offset / 4] += symbol_value;
+		break;
+	default:
+		break;
+	}
+
+	return symbol_value;
+}
+
 /*****************************************************************************
  * elfc_relocate_all
  *
@@ -85,8 +128,10 @@ void elfc_relocate_all(struct elf_cache *cache) {
 	}
 
 	/* add special entries to GOT for PLT resolution */
-	((uint32_t*) cache->pltgot)[1] = (uint32_t) cache->image;
-	((uint32_t*) cache->pltgot)[2] = (uint32_t) __plt_resolve;
+	if (cache->pltgot) {
+		((uint32_t*) cache->pltgot)[1] = (uint32_t) cache->image;
+		((uint32_t*) cache->pltgot)[2] = (uint32_t) __plt_resolve;
+	}
 
 	/* perform normal relocations (data) */
 	if (cache->reltab) {
@@ -103,7 +148,7 @@ void elfc_relocate_all(struct elf_cache *cache) {
 	}
 }
 
-void elfc_relocate_exec(struct elf_cache *cache) {
+void elfc_relocate_all_exec(struct elf_cache *cache) {
 	size_t i;
 
 	/* only relocate dynamic objects */
@@ -112,13 +157,15 @@ void elfc_relocate_exec(struct elf_cache *cache) {
 	}
 
 	/* add special entries to GOT for PLT resolution */
-	((uint32_t*) cache->pltgot)[1] = (uint32_t) cache->image;
-	((uint32_t*) cache->pltgot)[2] = (uint32_t) __plt_resolve;
+	if (cache->pltgot) {
+		((uint32_t*) cache->pltgot)[1] = (uint32_t) cache->image;
+		((uint32_t*) cache->pltgot)[2] = (uint32_t) __plt_resolve;
+	}
 
 	/* perform normal relocations (data) */
 	if (cache->reltab) {
 		for (i = 0; i < cache->reltabn; i++) {
-			elfc_relocate(cache, &cache->reltab[i]);
+			elfc_relocate_exec(cache, &cache->reltab[i]);
 		}
 	}
 }
@@ -317,7 +364,7 @@ void elf_gencache(struct elf_cache *cache, const struct elf32_ehdr *image) {
 
 	/* calulate image size */
 	for (i = 0; cache->segtab[i].p_type == PT_LOAD || cache->segtab[i].p_type == PT_DYNAMIC; i++);
-	if (i) cache->vsize = cache->segtab[i - 1].p_vaddr + cache->segtab[i - 1].p_memsz;
+	if (i) cache->vsize = cache->segtab[i - 1].p_vaddr + cache->segtab[i - 1].p_memsz + 0x1000;
 
 	/* get DYNAMIC segment */
 	cache->dynamic = NULL;
@@ -339,6 +386,7 @@ void elf_gencache(struct elf_cache *cache, const struct elf32_ehdr *image) {
 	cache->strtab = NULL;
 	cache->pltgot = NULL;
 	cache->hash   = NULL;
+	cache->soname = NULL;
 	for (i = 0; cache->dynamic[i].tag != DT_NULL; i++) {
 		switch (cache->dynamic[i].tag) {
 		case DT_SYMTAB:   cache->symtab  = (const struct elf32_sym*) (base + cache->dynamic[i].val); break;
@@ -355,3 +403,60 @@ void elf_gencache(struct elf_cache *cache, const struct elf32_ehdr *image) {
 
 	cache->soname = (cache->soname) ? &cache->strtab[(uintptr_t) cache->soname] : NULL;
 }
+
+/*****************************************************************************
+ * elf_gencache_exec
+ *
+ * Generate an ELF cached image from an ELF image, storing the cache data in
+ * <cache>. This cache data is used to make lookups of various information
+ * about the image much faster.
+ */
+
+void elf_gencache_exec(struct elf_cache *cache, const struct elf32_ehdr *image) {
+	size_t i;
+
+	cache->image = image;
+
+	/* get segment table */
+	cache->segtab = (const struct elf32_phdr*) (image->e_phoff + (uintptr_t) image);
+
+	/* calulate image size */
+	cache->vsize = 0;
+
+	/* get DYNAMIC segment */
+	cache->dynamic = NULL;
+	for (i = 0; cache->segtab[i].p_type != PT_NULL; i++) {
+		if (cache->segtab[i].p_type == PT_DYNAMIC) {
+			cache->dynamic = (const struct elf32_dyn*) cache->segtab[i].p_vaddr;
+			break;
+		}
+	}
+
+	if (!cache->dynamic) {
+		return;
+	}
+
+	/* get various DYNAMIC values */
+	cache->symtab = NULL;
+	cache->reltab = NULL;
+	cache->jmprel = NULL;
+	cache->strtab = NULL;
+	cache->pltgot = NULL;
+	cache->hash   = NULL;
+	cache->soname = NULL;
+	for (i = 0; cache->dynamic[i].tag != DT_NULL; i++) {
+		switch (cache->dynamic[i].tag) {
+		case DT_SYMTAB:   cache->symtab  = (const struct elf32_sym*) cache->dynamic[i].val; break;
+		case DT_REL:      cache->reltab  = (const struct elf32_rel*) cache->dynamic[i].val; break;
+		case DT_RELSZ:    cache->reltabn = cache->dynamic[i].val / 8; break;
+		case DT_JMPREL:   cache->jmprel  = (const struct elf32_rel*) cache->dynamic[i].val; break;
+		case DT_PLTRELSZ: cache->jmpreln = cache->dynamic[i].val / 8; break;
+		case DT_STRTAB:   cache->strtab  = (const char*) cache->dynamic[i].val; break;
+		case DT_PLTGOT:   cache->pltgot  = (const uint32_t*) cache->dynamic[i].val; break;
+		case DT_HASH:     cache->hash    = (const uint32_t*) cache->dynamic[i].val; break;
+		case DT_SONAME:   cache->soname  = (const char*) cache->dynamic[i].val; break;
+		}
+	}
+
+	cache->soname = (cache->soname) ? &cache->strtab[(uintptr_t) cache->soname] : NULL;
+}

dl/exec.c

@@ -65,18 +65,12 @@ int _exec(void *image, size_t size, int flags) {
 	}
 
 	/* load executable */
-	if (exec->e_type == ET_EXEC) {
-		elf_load(exec, 0);
-		exec  = (void*) 0x100000;
-		entry = (void*) exec->e_entry;
-	}
-	else {
-		elf_load(exec, 0x100000);
-		entry = (void*) (exec->e_entry + 0x100000);
+	elf_load(exec, 0);
+	exec  = (void*) 0x100000;
+	entry = (void*) exec->e_entry;
 
-		elf_gencache(&cache, exec);
-		elfc_relocate_all(&cache);
-	}
+	elf_gencache_exec(&cache, exec);
+	elfc_relocate_all_exec(&cache);
 
 	/* remove executable image */
 	page_free(temp, size);

dl/plt_resolve.c

@@ -19,6 +19,11 @@
 uint32_t _plt_resolve(struct elf32_ehdr *image, uint32_t index) {
 	struct elf_cache cache;
 
+	if (image == (void*) 0x100000) {
+		elf_gencache_exec(&cache, image);
+		return elfc_relocate_exec(&cache, &cache.jmprel[index / 8]);
+	}
+
 	elf_gencache(&cache, image);
-	return elfc_relocate(&cache, &cache.jmprel[index]);
+	return elfc_relocate(&cache, &cache.jmprel[index / 8]);
 }

fish/main.c

@@ -136,11 +136,6 @@ int main() {
 	size_t i, n;
 	char *argv[100];
 
-	uint32_t *object;
-
-	object = dlopen("/lib/libc.so", 0);
-	printf("libc.so:\t%p\n", object);
-
 	setenv("PWD", "/");
 
 	while (1) {

kernel/fault/fault_page.c

@@ -60,7 +60,7 @@ struct thread *fault_page(struct thread *image) {
 		debug_printf("user stack: %x - %x\n", image->stack, image->stack + SEGSZ);
 		debug_printf("user stack dump: (ebp = %x)\n", image->ebp);
 		debug_dumpi((void*) image->useresp, 30);
-//		debug_panic("page fault exception");
+		debug_panic("page fault exception");
 
 		process_freeze(image->proc);
 		return thread_send(image, image->proc->pid, PORT_PAGE, NULL);

libc/c0.s

@@ -18,6 +18,18 @@ section .text
 
 global _start
 extern _init
+extern main
+
+extern _GLOBAL_OFFSET_TABLE_
 
 _start:
+
+	call .getgot
+.getgot:
+	pop ebx
+	add ebx, _GLOBAL_OFFSET_TABLE_+$$-.getgot wrt ..gotpc
+
+	mov eax, [ebx+main wrt ..got]
+	push eax
+
 	call _init wrt ..plt; libc initialization, runs main and exits

libc/exec/exec.c

@@ -71,7 +71,6 @@ int execiv(uint8_t *image, size_t size, char const **argv) {
 		free(pack);
 	}
 
-
 	if (dl->exec(image, size, 0)) {
 		errno = ENOEXEC;
 		return -1;

libc/init/init.c

@@ -105,7 +105,7 @@ static char *__type(rp_t source, int argc, char **argv) {
  * library.
  */
 
-void _init() {
+void _init(int (*_main)(int, char**)) {
 	extern int main(int argc, char **argv);
 	extern void _on_event(void);
 	struct slt32_entry *slt;
@@ -189,5 +189,5 @@ void _init() {
 	}
 
 	/* execute main program */
-	exit(main(argc, argv));
+	exit(_main(argc, argv));
 }

libc/ipc/_on_event.s

@@ -19,6 +19,8 @@ global _on_event
 extern on_event
 extern _done
 
+extern _GLOBAL_OFFSET_TABLE_
+
 section .text
 
 _on_event:
@@ -28,6 +30,12 @@ _on_event:
 	push esi
 	push edx
 	push ecx
+
+	call _on_event.getgot
+.getgot:
+	pop ebx
+	add ebx, _GLOBAL_OFFSET_TABLE_+$$-.getgot wrt ..gotpc
+
 	call on_event wrt ..plt
 	add esp, 20
 

librdi/Makefile

@@ -27,7 +27,7 @@ $(STATIC): $(HEADERS) $(SOURCES)
 
 $(SHARED): $(HEADERS) $(SOURCES)
 	@ echo " LD	" $(SUBDIR)/$(SHARED)
-	@ $(LD) $(LDFLAGS) -shared $(SOURCES) -o $(SHARED)
+	@ $(LD) $(LDFLAGS) -shared $(SOURCES) -o $(SHARED) -soname librdi.so.1
 	@ echo " CP	" $(SUBDIR)/$(SHARED) "->" $(BUILDDIR)/lib
 	@ cp $(SHARED) $(BUILDDIR)/lib
 

util/echo/Makefile

@@ -4,7 +4,7 @@ SOURCES += $(BUILDDIR)/lib/c0.o
 SUBDIR	:= util/echo
 TARGET	:= echo
 CFLAGS  += -I$(BUILDDIR)/$(SUBDIR)/inc
-LDFLAGS += -lc -pie
+LDFLAGS += -Bdynamic -lc
 ASFLAGS := -felf
 
 all: $(TARGET)