Elfparse

include/libc/stubinfo.h

@@ -29,7 +29,9 @@
 #define STUBINFO_FLAGS 0x8C
 #define STUBINFO_UENTRY 0x90
 #define STUBINFO_CPL_FD 0x94
-#define STUBINFO_END 0x98
+#define STUBINFO_UPL_BASE 0x98
+#define STUBINFO_UPL_SIZE 0x9C
+#define STUBINFO_END 0xA0
 #ifndef __ASSEMBLER__
 #include <stdint.h>
 typedef struct {
@@ -61,6 +63,8 @@ typedef struct {
   uint32_t flags;
   uint32_t uentry;
   int32_t cpl_fd;
+  uint32_t upl_base;
+  uint32_t upl_size;
 } _GO32_StubInfo;
 
 _Static_assert(sizeof(_GO32_StubInfo) == STUBINFO_END, "size mismatch");

src/djdev64/djdev64.c

@@ -183,7 +183,10 @@ static int _djdev64_open(const char *path, const struct dj64_api *api,
 #endif
 #else
 #ifdef RTLD_DEEPBIND
-        dlh = emu_dlmopen(handles, path, RTLD_LOCAL | RTLD_NOW | RTLD_DEEPBIND,
+        if (flags & DJ64F_NOMANGLE)
+            dlh = dlopen(path, RTLD_LOCAL | RTLD_NOW | RTLD_DEEPBIND);
+        else
+            dlh = emu_dlmopen(handles, path, RTLD_LOCAL | RTLD_NOW | RTLD_DEEPBIND,
                 &path2);
 #else
         fprintf(stderr, "RTLD_DEEPBIND not supported, use static linking\n");

src/djdev64/elf.c

@@ -26,6 +26,7 @@
 #include <libelf.h>
 #include <gelf.h>
 #include <assert.h>
+#include "djdev64/djdev64.h"
 #include "elf_priv.h"
 
 struct elfstate {
@@ -34,6 +35,7 @@ struct elfstate {
     Elf_Scn *symtab_scn;
     GElf_Shdr symtab_shdr;
     char *addr;
+    int need_unmap;
 };
 
 static int do_getsym(struct elfstate *state, const char *name, GElf_Sym *r_sym)
@@ -87,6 +89,7 @@ static int do_elf_open(char *addr, uint32_t size, struct elfstate *ret)
     ret->elf = elf;
     ret->symtab_scn = scn;
     ret->symtab_shdr = shdr;
+    ret->addr = addr;
     return 0;
 
 err:
@@ -125,7 +128,7 @@ void *djelf_open_dyn(int fd)
         return NULL;
     ret = (struct elfstate *)malloc(sizeof(*ret));
     *ret = es;
-    ret->addr = addr;
+    ret->need_unmap = 1;
     return ret;
 }
 
@@ -134,7 +137,7 @@ void djelf_close(void *arg)
     struct elfstate *state = (struct elfstate *)arg;
 
     elf_end(state->elf);
-    if (state->addr)
+    if (state->need_unmap)
         munmap(state->addr, state->mapsize);
     free(state);
 }
@@ -152,3 +155,29 @@ uint32_t djelf_getsymoff(void *arg, const char *name)
     struct elfstate *state = (struct elfstate *)arg;
     return do_getsymoff(state, name);
 }
+
+int djelf_reloc(void *arg, char *addr, uint32_t size, uint32_t va,
+        uint32_t *r_entry)
+{
+    struct elfstate *state = (struct elfstate *)arg;
+    GElf_Ehdr ehdr;
+    GElf_Phdr phdr;
+    int offs;
+    int i;
+
+    gelf_getehdr(state->elf, &ehdr);
+    for (i = 0; i < ehdr.e_phnum; i++) {
+        gelf_getphdr(state->elf, i, &phdr);
+        if (phdr.p_type != PT_LOAD)
+            continue;
+        offs = phdr.p_vaddr - va;
+        if (offs < 0 || offs + phdr.p_memsz > size)
+            return -1;
+        memcpy(addr + offs, state->addr + phdr.p_offset, phdr.p_filesz);
+        if (phdr.p_memsz > phdr.p_filesz)
+            memset(addr + offs + phdr.p_filesz, 0, phdr.p_memsz -
+                    phdr.p_filesz);
+    }
+    *r_entry = ehdr.e_entry;
+    return 0;
+}

src/djdev64/elf64.c

@@ -0,0 +1,82 @@
+/*
+ *  ELF64 parser for dj64dev.
+ *  Copyright (C) 2025  @stsp
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include <libelf.h>
+#include <gelf.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "djdev64/djdev64.h"
+
+static const char *sec_name = ".dj64startup";
+
+char *djelf64_parse(const char *path, uint32_t *r_size)
+{
+    int fd;
+    Elf *e;
+    char *ret;
+    char *name;
+    Elf_Scn *scn;
+    GElf_Shdr shdr;
+    Elf_Data *data;
+    size_t shstrndx;
+
+    if (elf_version(EV_CURRENT) == EV_NONE)
+        return NULL;
+    if ((fd = open(path, O_RDONLY | O_CLOEXEC)) < 0)
+        return NULL;
+    if ((e = elf_begin(fd, ELF_C_READ, NULL)) == NULL)
+        goto err1;
+    if (elf_kind(e) != ELF_K_ELF)
+        goto err2;
+    if (elf_getshdrstrndx(e, &shstrndx) != 0)
+        goto err2;
+    scn = NULL;
+    while ((scn = elf_nextscn(e, scn)) != NULL) {
+        gelf_getshdr(scn, &shdr);
+        if (shdr.sh_type != SHT_PROGBITS)
+            continue;
+        name = elf_strptr(e, shstrndx, shdr.sh_name);
+        if (name && strcmp(name, sec_name) == 0)
+            break;
+    }
+    if (!scn) {
+        fprintf(stderr, "dj64-specific sections not found in %s\n", path);
+        goto err2;
+    }
+    data = elf_getdata(scn, NULL);
+    if (!data) {
+        fprintf(stderr, "failed to get section data for %s\n", path);
+        goto err2;
+    }
+    close(fd);
+    *r_size = data->d_size;
+    ret = malloc(data->d_size);
+    memcpy(ret, data->d_buf, data->d_size);
+    elf_end(e);
+    return ret;
+
+err2:
+    elf_end(e);
+err1:
+    close(fd);
+    return NULL;
+}

src/djdev64/elf_priv.h

@@ -1,6 +1,4 @@
 #include <stdint.h>
 
-void *djelf_open(char *addr, uint32_t size);
 void *djelf_open_dyn(int fd);
-void djelf_close(void *arg);
 uint32_t djelf_getsymoff(void *arg, const char *name);

src/djdev64/include/djdev64/dj64init.h

@@ -25,7 +25,7 @@
 
 typedef int (dj64cdispatch_t)(int handle, int libid, int fn, unsigned esi,
         uint8_t *sp);
-#define DJ64_API_VER 16
+#define DJ64_API_VER 17
 #define DJ64_API_MIN_VER 16
 enum { DJ64_PRINT_LOG, DJ64_PRINT_TERMINAL, DJ64_PRINT_SCREEN };
 
@@ -65,6 +65,8 @@ struct dj64_api {
     void (*free)(void *ptr);
     int (*elfload)(int num);
     int (*uget)(int handle);
+    char *(*elfparse64)(int num, uint32_t addr, uint32_t size,
+            uint32_t mem_base, uint32_t *r_size, uint32_t *r_entry);
 };
 #define DJ64_INIT_ONCE_FN dj64init_once
 typedef int (dj64init_once_t)(const struct dj64_api *api, int api_ver);

src/djdev64/include/djdev64/djdev64.h

@@ -22,7 +22,8 @@
 #include "djdev64/dj64init.h"
 
 /* first 16 bits are for internal use */
-#define DJ64F_DLMOPEN (1 << 16)
+#define DJ64F_DLMOPEN  (1 << 16)
+#define DJ64F_NOMANGLE (1 << 17)
 
 int djdev64_open(const char *path, const struct dj64_api *api, int api_ver,
         unsigned flags);
@@ -34,4 +35,10 @@ void djdev64_close(int handle);
 
 int djdev64_exec(const char *path, unsigned flags, int argc, char **argv);
 
+char *djelf64_parse(const char *path, uint32_t *r_size);
+void *djelf_open(char *addr, uint32_t size);
+void djelf_close(void *arg);
+int djelf_reloc(void *arg, char *addr, uint32_t size, uint32_t va,
+        uint32_t *r_entry);
+
 #endif

src/djdev64/makefile

@@ -1,7 +1,7 @@
 TOP = ../..
 prefix ?= /usr/local
 PKG_CONFIG ?= pkg-config
-SOURCES = djdev64.c elf.c djexec.c
+SOURCES = djdev64.c elf.c djexec.c elf64.c
 OBJECTS = $(SOURCES:.c=.o)
 LIBELF := $(shell $(PKG_CONFIG) --silence-errors --libs libelf)
 ifeq ($(LIBELF),)

src/djdev64/stub/stub.c

@@ -359,10 +359,13 @@ int djstub_main(int argc, char *argv[], char *envp[],
     if (va_size > MB)
         exit(EXIT_FAILURE);
     /* if we load 2 payloads, use larger estimate */
-    if (dyn && (pl32 || BARE_STUB()))
+    if (dyn && (pl32 || BARE_STUB())) {
         stubinfo.initial_size = VA_SZ;
-    else
+        stubinfo.upl_base = va + MB;
+        stubinfo.upl_size = VA_SZ - MB;
+    } else {
         stubinfo.initial_size = max(va_size, 0x10000);
+    }
     info.size = PAGE_ALIGN(stubinfo.initial_size);
     /* allocate mem */
     __dpmi_allocate_memory(&info);

src/libc/dj64/plt.S

@@ -26,10 +26,13 @@
 __plt_open: .quad 0
 PLT_OPEN_CMD = 0
 PLT_CLOSE_CMD = 1
+PLT_ELOAD_CMD = 4
+PLT_ECLOSE_CMD = 5
 __plt_call: .quad 0
 __plt_ctrl: .quad 0
 .global __plt_handle
 __plt_handle: .long 0
+elfload: .long 0
 
 sel: .word 0
 SHM_REQ_LEN = 0
@@ -184,6 +187,7 @@ plt_init:
     movl %edi, __plt_call
     movl %eax, __plt_ctrl + 4
     movl %esi, __plt_ctrl
+
     movl %fs:STUBINFO_FLAGS, %ecx
     testw $0x4080, %cx
     jnz 111f
@@ -248,8 +252,9 @@ plt_init:
     movl %fs:STUBINFO_SELF_SIZE, %ecx
     movl %fs:STUBINFO_MEM_BASE, %edx
     movl %fs:STUBINFO_CPL_FD, %esi
-    movl $-1, %edi  // user payload in mem buffer
+    pushl $DL_SET_SYMTAB
     call ctrl
+    popl %eax
     jc 2f
     /* free mem */
     movl $0x502, %eax
@@ -264,7 +269,44 @@ plt_init:
     ret
 
 321:
-    // no payload found
+    // no payload found, try dynamic
+    movl $0, %eax
+    movl $PLT_ELOAD_CMD, %ebx
+    movl $0, %ecx  // reserve
+    lcalll *__plt_open
+    jc 222f
+    movl %eax, __plt_handle
+    movl %es, %eax
+    movl %eax, __plt_call + 4
+    movl %edi, __plt_call
+    movl %eax, __plt_ctrl + 4
+    movl %esi, __plt_ctrl
+    /* resolve cpl */
+    movl %fs:STUBINFO_FLAGS, %eax
+    movl $0, %ebx
+    movl $0, %ecx
+    movl %fs:STUBINFO_MEM_BASE, %edx
+    movl %fs:STUBINFO_CPL_FD, %esi
+    pushl $DL_SET_SYMTAB
+    call ctrl
+    popl %eax
+    jc 222f
+    /* resolve upl */
+    movl $0, %eax
+    movl %fs:STUBINFO_UPL_BASE, %ebx
+    movl %fs:STUBINFO_UPL_SIZE, %ecx
+    movl %fs:STUBINFO_MEM_BASE, %edx
+    pushl $DL_ELFLOAD
+    call ctrl
+    popl %ecx
+    // failure is not fatal, just no upl
+    jc 555f
+    movl %eax, %fs:STUBINFO_UENTRY
+    call uplt_init
+555:
+    movl $1, elfload
+    jmp 11b
+222:
     movl $err2_str, %edx
     jmp perr
 
@@ -289,33 +331,40 @@ perr:
     movl $0, %ecx
     movl %fs:STUBINFO_MEM_BASE, %edx
     movl %fs:STUBINFO_CPL_FD, %esi
-    movl $-1, %edi  // no user payload
+    pushl $DL_SET_SYMTAB
     call ctrl
+    popl %eax
     jc 2b
     jmp 11b
 
 ctrl:
+    pushl %ebp
+    movl %esp, %ebp
     pushal
     movl %esp, %edx
     movl __plt_handle, %eax
     movl $0, %ebx
     movb $AUX_CORE, %bl
     movb $DL_API_VER, %bh
-    movl $DL_SET_SYMTAB, %ecx
+    movl 8(%ebp), %ecx
     movl %cs, %esi
     lcalll *__plt_ctrl
     testl %eax, %eax
     jnz 1f
     popal
+    popl %ebp
     clc
     ret
 1:
     popal
+    popl %ebp
     stc
     ret
 
 .global plt_done
 plt_done:
+    cmpl $0, elfload
+    jne 1f
     // close lib
     movl __plt_handle, %eax
     movl $PLT_CLOSE_CMD, %ebx
@@ -333,6 +382,11 @@ plt_done:
     movw shm_block2 + SHM_HANDLE + 2, %si
     int $0x31
     ret
+1:
+    movl __plt_handle, %eax
+    movl $PLT_ECLOSE_CMD, %ebx
+    lcalll *__plt_open
+    ret
 
 .bss
 

src/libc/dj64/plt.h

@@ -1,2 +1,4 @@
 #define DL_SET_SYMTAB 0
+#define DL_ELFLOAD 1
+
 #define DL_API_VER 1