1 files changed, 152 insertions, 0 deletions
diff --git a/com32/lib/sys/module/shallow_module.c b/com32/lib/sys/module/shallow_module.c
new file mode 100644
index 00000000..c4a9ff15
--- /dev/null
+++ b/com32/lib/sys/module/shallow_module.c
@@ -0,0 +1,152 @@
+/*
+ * shallow_module.c
+ *
+ *  Created on: Aug 11, 2008
+ *      Author: Stefan Bucur <stefanb[at]zytor.com>
+ */
+
+#include "common.h"
+
+#include <sys/module.h>
+#include <sys/elfutils.h>
+
+
+static int check_header_shallow(Elf32_Ehdr *elf_hdr) {
+	int res;
+
+	res = check_header_common(elf_hdr);
+
+	if (res != 0)
+		return res;
+
+	if (elf_hdr->e_shoff == 0x00000000) {
+		DBG_PRINT("SHT missing\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int load_shallow_sections(struct elf_module *module, Elf32_Ehdr *elf_hdr) {
+	int i;
+	int res = 0;
+	void *sht = NULL;
+	void *buffer = NULL;
+	Elf32_Shdr *crt_sht;
+	Elf32_Off buff_offset;
+
+	Elf32_Off min_offset = 0xFFFFFFFF;
+	Elf32_Off max_offset = 0x00000000;
+	Elf32_Word max_align = 0x1;
+
+	Elf32_Off sym_offset = 0xFFFFFFFF;
+	Elf32_Off str_offset = 0xFFFFFFFF;
+
+
+	char *sh_strtable;
+
+	// We buffer the data up to the SHT
+	buff_offset = module->_cr_offset;
+
+	buffer = malloc(elf_hdr->e_shoff - buff_offset);
+	// Get to the SHT
+	image_read(buffer, elf_hdr->e_shoff - buff_offset, module);
+
+	// Load the SHT
+	sht = malloc(elf_hdr->e_shnum * elf_hdr->e_shentsize);
+	image_read(sht, elf_hdr->e_shnum * elf_hdr->e_shentsize, module);
+
+	// Get the string table of the section names
+	crt_sht = (Elf32_Shdr*)(sht + elf_hdr->e_shstrndx * elf_hdr->e_shentsize);
+	sh_strtable = (char*)(buffer + (crt_sht->sh_offset - buff_offset));
+
+	for (i = 0; i < elf_hdr->e_shnum; i++) {
+		crt_sht = (Elf32_Shdr*)(sht + i*elf_hdr->e_shentsize);
+
+		if (strcmp(".symtab", sh_strtable + crt_sht->sh_name) == 0) {
+			// We found the symbol table
+			min_offset = MIN(min_offset, crt_sht->sh_offset);
+			max_offset = MAX(max_offset, crt_sht->sh_offset + crt_sht->sh_size);
+			max_align = MAX(max_align, crt_sht->sh_addralign);
+
+			sym_offset = crt_sht->sh_offset;
+
+			module->syment_size = crt_sht->sh_entsize;
+			module->symtable_size = crt_sht->sh_size / crt_sht->sh_entsize;
+		}
+		if (strcmp(".strtab", sh_strtable + crt_sht->sh_name) == 0) {
+			// We found the string table
+			min_offset = MIN(min_offset, crt_sht->sh_offset);
+			max_offset = MAX(max_offset, crt_sht->sh_offset + crt_sht->sh_size);
+			max_align = MAX(max_align, crt_sht->sh_addralign);
+
+			str_offset = crt_sht->sh_offset;
+
+			module->strtable_size = crt_sht->sh_size;
+		}
+	}
+
+	if (elf_malloc(&module->module_addr, max_align,
+			max_offset - min_offset) != 0) {
+		DBG_PRINT("Could not allocate sections\n");
+		goto out;
+	}
+
+	// Copy the data
+	image_seek(min_offset, module);
+	image_read(module->module_addr, max_offset - min_offset, module);
+
+	// Setup module information
+	module->module_size = max_offset - min_offset;
+	module->str_table = (char*)(module->module_addr + (str_offset - min_offset));
+	module->sym_table = module->module_addr + (sym_offset - min_offset);
+
+out:
+	// Release the SHT
+	if (sht != NULL)
+		free(sht);
+
+	// Release the buffer
+	if (buffer != NULL)
+		free(buffer);
+
+	return res;
+}
+
+
+int module_load_shallow(struct elf_module *module) {
+	int res;
+	Elf32_Ehdr elf_hdr;
+
+	res = image_load(module);
+
+	if (res < 0)
+		return res;
+
+	module->shallow = 1;
+
+	CHECKED(res, image_read(&elf_hdr, sizeof(Elf32_Ehdr), module), error);
+
+	// Checking the header signature and members
+	CHECKED(res, check_header_shallow(&elf_hdr), error);
+
+	CHECKED(res, load_shallow_sections(module, &elf_hdr), error);
+
+	// Check the symbols for duplicates / missing definitions
+	CHECKED(res, check_symbols(module), error);
+
+	// Add the module at the beginning of the module list
+	list_add(&module->list, &modules);
+
+	// The file image is no longer needed
+	image_unload(module);
+
+	DBG_PRINT("SHALLOW MODULE %s LOADED SUCCESSFULLY\n", module->name);
+
+	return 0;
+
+error:
+	image_unload(module);
+
+	return res;
+}