Build posix-runner at the end of stage0-uefi.

Some stage0 applications, e.g. M0 assume that newly allocated memory
is empty.

We also need to do that for forked processes but it's not part of this commit.

M2-Planet

@@ -1 +1 @@
-Subproject commit e6447d98cf4b2f41e816d8fd336f7251d21d15b2
+Subproject commit 0479606ed5131a64cd1dd2dd3f257e73cd9dce68

M2libc

@@ -1 +1 @@
-Subproject commit ff47b1cca5fc6f7591b8572710eabf73198e2de2
+Subproject commit c103ee8d5699c5313335d5798b63a8421fd62faa

after.kaem

@@ -0,0 +1,5 @@
+cd /posix-runner
+M2LIBC_PATH=${M2LIBC}
+PATH=${BINDIR}
+${BINDIR}/M2-Mesoplanet.efi --os UEFI --architecture ${ARCH} --file posix-runner.c --output ${BINDIR}/posix-runner.efi
+cd ..

amd64.answers

@@ -1,18 +1,19 @@
-559629a1660cfd18c2399efa641489303f8384af8ba215f3670473d7e1b95553  amd64/bin/blood-elf.efi
-eed56eb5f2d2310de367765588eea56d8b538d83312fae09effb42fd4e1c1e6d  amd64/bin/catm.efi
-8ef921e260361b59a4f6d1a89f1507f272f45f36a8c47549ff305f874e202db2  amd64/bin/chmod.efi
-71e52f6e5e115cffdf8873a7bce3aef6fb91edd3cb6ed71eaec38a338982e095  amd64/bin/cp.efi
-584ff2bbe12bf842e643c27cd23d9af877f7e9539101b39fc21f08131bc25b58  amd64/bin/get_machine.efi
-1cc45ff9c4fd1bd1f3ad01eb4a336d15c66bfbbaa23efb402a9d302f2c90dc60  amd64/bin/hex2.efi
-13e54d0ca87e30903058f4f2034dea4f8fce173b06e397866f8a9927bae192b3  amd64/bin/kaem.efi
-d55697f2df4546dbcc188df30d2c12943f28f26c07bbe3b9db3d9ef7d496b1da  amd64/bin/M1.efi
-d5acba35bffddd577c4766be78c97c5537625e70f3ed5e073ccb3182acc9602f  amd64/bin/M2-Mesoplanet.efi
-a2d929b28f98c249a1b52880c57b670b659f405d5b13f444da2118d6feb7f5d9  amd64/bin/M2-Planet.efi
-bdf18f12fe339491ab3570e9c73b44b2b812af9b778dd0eaf6eb11e4722aa0bc  amd64/bin/match.efi
-aa30d3a3cbaca514661fbd866402218628df7f733ddebf939337953eed5422c7  amd64/bin/mkdir.efi
-3ffb47b2ce3efc7e455e9d64e7087e2c5582cda71f99171775c43515dfd365ba  amd64/bin/replace.efi
-65c6605828d91d5cc14c361634470f9fdc5c10ad9a60d4e74ae240eea2c1f095  amd64/bin/rm.efi
-9146cb3a686d24650d8e1bff07599baecee1c3c3633451a0e6648cee305bb5f5  amd64/bin/sha256sum.efi
-3312998cab45a4baa9946c68d09d9c2df0043ad579fd329532fa60671c6e6d6e  amd64/bin/unbz2.efi
-f3ed1e47c4bcf3f244d9d17a28dc98e526ce5744ce50286b9b6817408f626935  amd64/bin/ungz.efi
-6dca66a518bba1ad484757fe728aad03e7e6000f9741f94d3896bf8ca3aed265  amd64/bin/untar.efi
+f55f51d25cb520adcc811c98284d01af1fa19e96b4034b24af96c796791886ec  amd64/bin/blood-elf.efi
+8a7e900730aa29f186993d181fc4ac42d56914b2c7138f4dd441acf22622b97d  amd64/bin/catm.efi
+fe8a9f95d32aa48e48732e1076e7af06ab6ec9a7186f928c5141643264ec1f64  amd64/bin/chmod.efi
+64df4d8a355ea6d96eadb6b2dcdbd1bd7d0b33f380fa13d218f19eb69200196a  amd64/bin/cp.efi
+45bfdaf8354b99017ce914fbf6a0b435c0baa7baa8e056fd84ed465e77f3cc07  amd64/bin/get_machine.efi
+191946531f7e0ce33a633e997b2600cae32f386de469e33ecab799f250abb5e6  amd64/bin/hex2.efi
+30452e0094ac95a20553776930bca825852612bba9bb0fa710a402702c66050a  amd64/bin/kaem.efi
+1407fb16c11bc621a03775ef2d8540d77853f1d5d5c245045d7e6e7394695158  amd64/bin/M1.efi
+e7559c5aaf546acccf739d2d41f07185c3a6b07bb4b2602ce4621c4f2a254225  amd64/bin/M2-Mesoplanet.efi
+c97c3d117a23e0c1b5916e2e1f0b08f1173829afbd0a0cf9d3539031d6c409a8  amd64/bin/M2-Planet.efi
+b120fecb59025a3fe472cdf1b7b3ca7c6a234c12c5b1ce134dd159431076f1ef  amd64/bin/match.efi
+0efba4291b071c04086abd9ee4fa86ced33640341c7c0684323e77016f035ee9  amd64/bin/mkdir.efi
+e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  amd64/bin/placeholder
+d0361b7f5b6554bd7c0352a0669f7311c4156c695410b1c098850157e256d0ee  amd64/bin/replace.efi
+f50990d93cdd8a58a50d1a94ee3e2156a174ea79f64cb788b03a69e429e6d3a6  amd64/bin/rm.efi
+7af6cab98031a0fdc08c00732ca361dd35dff9aa67ca5b94bcfd9b3a09842362  amd64/bin/sha256sum.efi
+fe7835923398f65b337c3966a98162f11bd9c7f55ea125b1e9fd55f7e00e7da1  amd64/bin/unbz2.efi
+59e7e92605e808d1cce30554027dad5265bc7a72b9d19af28bda3b8daec97c4f  amd64/bin/ungz.efi
+53eaed2a1518b252996208eec9f42737971152b978ef91038e48490f4a74a566  amd64/bin/untar.efi

amd64/mescc-tools-full-kaem.kaem

@@ -36,7 +36,6 @@
 	-f ./M2libc/${ARCH}/${ARCH}_defs.M1 \
 	-f ./M2libc/${ARCH}/uefi/libc-full.M1 \
 	-f ./${ARCH_DIR}/artifact/M2-1.M1 \
-	-f ./${ARCH_DIR}/artifact/M2-1-footer.M1 \
 	-o ./${ARCH_DIR}/artifact/M2-1.hex2
 
 ./${ARCH_DIR}/bin/hex2.efi --architecture ${ARCH} \

posix-runner/posix-runner.c

@@ -0,0 +1,470 @@
+/*
+ * SPDX-FileCopyrightText: 2023 Andrius Štikonas <andrius@stikonas.eu>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <bootstrappable.h>
+
+#define MSR_EFER (0x60000080 + 0x60000000)
+#define MSR_STAR (0x60000081 + 0x60000000)
+#define MSR_LSTAR (0x60000082 + 0x60000000)
+
+void* syscall_table;
+
+#define MAX_MEMORY_PER_PROC (768 * 1024 * 1024)
+#define __FILEDES_MAX 4096
+
+struct mem_block {
+    void* address;
+    int length;
+};
+
+struct process {
+    struct process* parent;
+    void* entry_point;
+    void* brk;
+    void* saved_brk;
+    void* stack;
+    void* saved_stack_pointer;
+    mem_block program;
+    mem_block saved_stack;
+    mem_block saved_memory;
+    int child_exit_code;
+    int forked;
+    int fd_map[__FILEDES_MAX];
+};
+struct process* current_process;
+
+void* _brk;
+
+void* _get_stack()
+{
+    asm("mov_rax,rsp");
+}
+
+void* get_stack()
+{
+    /* Adjust to stack depth of _get_stack function */
+    return _get_stack() + (7 * sizeof(void *));
+}
+
+int extract_field(char* file_data, int position, int length)
+{
+    void* data;
+    memcpy(&data, file_data + position, length);
+    return data;
+}
+
+int load_elf(FILE* file_in, struct process* current)
+{
+    int file_size = fseek(file_in, 0, SEEK_END);
+    char* file_data = calloc(1, file_size + 0x1000); /* Allocate extra space in case application tries to use it */
+    if (file_data == NULL) {
+        fputs("Could not allocate memory to load ELF file.", stderr);
+        exit(1);
+    }
+    rewind(file_in);
+    fread(file_data, 1, file_size, file_in);
+    fclose(file_in);
+
+    if ((file_data[0] != 0x7F) || (file_data[1] != 'E') ||
+        (file_data[2] != 'L') || (file_data[3] != 'F')) {
+        return 1;
+    }
+    current->program.address = file_data;
+    current->program.length = file_size;
+    return 0;
+}
+
+void* entry_point(char* raw_elf)
+{
+    int entry_point = extract_field(raw_elf, 24, 8);
+    int header_table = extract_field(raw_elf, 32, 8);
+    int base_address = extract_field(raw_elf, header_table + 0x10, 8);
+    return entry_point - base_address + raw_elf;
+}
+
+void jump(void* start_address, int argc, int argc0, char** argv, char** envp)
+{
+    int argc_new;
+    current_process->stack = get_stack();
+    char* temp;
+    asm("push !0");
+    for (; *envp != 0; envp += sizeof(char *)) {
+        temp = *envp;
+        asm("push_rax");
+    }
+    int i;
+    for (i = argc; i >= argc0; i -= 1) {
+        temp = argv[i];
+        asm("push_rax");
+    }
+    argc_new = argc - argc0;
+    asm("push_rax");
+
+    asm("lea_rcx,[rbp+DWORD] %-8"
+        "mov_rcx,[rcx]"
+        "jmp_rcx"
+    );
+}
+
+void init_io()
+{
+    current_process->fd_map[STDIN_FILENO] = STDIN_FILENO;
+    current_process->fd_map[STDOUT_FILENO] = STDOUT_FILENO;
+    current_process->fd_map[STDERR_FILENO] = STDERR_FILENO;
+}
+
+int find_free_fd()
+{
+    int i;
+    for (i = 3; i < __FILEDES_MAX; i += 1) {
+        if (current_process->fd_map[i] == NULL) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+int sys_read(int fd, char* buf, unsigned count, void, void, void)
+{
+    return read(current_process->fd_map[fd], buf, count);
+}
+
+int sys_write(int fd, char* buf, unsigned count, void, void, void)
+{
+    return write(current_process->fd_map[fd], buf, count);
+}
+
+int sys_open(char* name, int flag, int mode, void, void, void)
+{
+    int rval;
+    int fd;
+    rval = open(name, flag, mode);
+    fd = find_free_fd();
+    current_process->fd_map[fd] = rval;
+    return fd;
+}
+
+int sys_close(int fd, void, void, void, void, void)
+{
+    int rval;
+    rval = close(current_process->fd_map[fd]);
+    current_process->fd_map[fd] = NULL;
+    return rval;
+}
+
+int sys_lseek(int fd, int offset, int whence, void, void, void)
+{
+    return lseek(current_process->fd_map[fd], offset, whence);
+}
+
+int sys_brk(void* addr, void, void, void, void, void)
+{
+    if (current_process->brk == NULL) {
+        current_process->brk = _brk;
+    }
+    if (addr == NULL) {
+        return current_process->brk;
+    }
+    else {
+        current_process->brk = addr;
+        return current_process->brk;
+    }
+}
+
+int sys_access(char* pathname, int mode, void, void, void, void)
+{
+    return access(pathname, mode);
+}
+
+int sys_fork(void, void, void, void, void, void)
+{
+    current_process->saved_brk = current_process->brk;
+    current_process->saved_stack_pointer = get_stack();
+    current_process->forked = TRUE;
+    current_process->saved_stack.length = current_process->stack - current_process->saved_stack_pointer;
+    current_process->saved_stack.address = malloc(current_process->saved_stack.length);
+    if (current_process->saved_stack.address == NULL ) {
+        fputs("Could not allocate memory for saved process stack.", stderr);
+        exit(1);
+    }
+    memcpy(current_process->saved_stack.address, current_process->saved_stack_pointer, current_process->saved_stack.length);
+    current_process->saved_memory.length = current_process->brk - _brk;
+    current_process->saved_memory.address = malloc(current_process->saved_memory.length);
+    if (current_process->saved_stack.address == NULL ) {
+        fputs("Could not allocate memory for saved process memory.", stderr);
+        exit(1);
+    }
+    memcpy(current_process->saved_memory.address, _brk, current_process->saved_memory.length);
+
+    return 0; /* return as child */
+}
+
+int sys_execve(char* file_name, char** argv, char** envp, void, void, void)
+{
+    if (current_process->forked) {
+        struct process* new;
+        new = calloc(1, sizeof(struct process));
+        if (new == NULL) {
+            fputs("Could not allocate memory for new process metadata.", stderr);
+            exit(1);
+        }
+        new->parent = current_process;
+        current_process->forked = FALSE; /* fork was handled */
+        current_process = new;
+        init_io();
+    }
+    // else {
+        // restore_stack(current_process->saved_stack); // FIXME
+    // }
+    FILE* file_in;
+    file_in = fopen(file_name, "r");
+    if (file_in == NULL) {
+        return -1;
+    }
+    int rval;
+    rval = load_elf(file_in, current_process);
+    if (rval == 1) {
+        return -1;
+    }
+    current_process->entry_point = entry_point(current_process->program.address);
+
+    int argc;
+    for(argc = 0; argv[argc] != 0; argc += 1) {}
+    jump(current_process->entry_point, argc, 0, argv, envp);
+}
+
+void sys_exit(unsigned value, void, void, void, void, void)
+{
+    if (current_process->parent == NULL) {
+        exit(value);
+    }
+    current_process->parent->child_exit_code = value;
+    struct process* child;
+    child = current_process;
+    current_process = current_process->parent;
+    free(child);
+
+    memcpy(current_process->saved_stack_pointer, current_process->saved_stack.address, current_process->saved_stack.length);
+    memcpy(_brk, current_process->saved_memory.address, current_process->saved_memory.length);
+    free(current_process->saved_stack.address);
+    free(current_process->saved_memory.address);
+    current_process->brk = current_process->saved_brk;
+    current_process->saved_stack_pointer;
+    /* Simulate return from sys_fork() */
+    asm("mov_rsp,rax"
+        "mov_rax, %1"
+        "ret"
+    );
+}
+
+int sys_wait4(int pid, int* status_ptr, int options)
+{
+    *status_ptr = current_process->child_exit_code << 8;
+    return 0;
+}
+
+int sys_uname(struct utsname* unameData)
+{
+    return uname(unameData);
+}
+
+int sys_getcwd(char* buf, int size, void, void, void, void)
+{
+    return getcwd(buf, size);
+}
+
+int sys_chdir(char* path, void, void, void, void, void)
+{
+    return chdir(path);
+}
+
+int sys_fchdir(int fd, void, void, void, void, void)
+{
+    return fchdir(current_process->fd_map[fd]);
+}
+
+int sys_mkdir(char const* a, mode_t b, void, void, void, void)
+{
+    return mkdir(a, b);
+}
+
+int sys_unlink(char* filename, void, void, void, void, void)
+{
+    return unlink(filename);
+}
+
+int sys_chroot(char const *path)
+{
+    return chroot(path);
+}
+
+void init_syscalls()
+{
+    syscall_table = calloc(300, sizeof(void *));
+    if (syscall_table == NULL) {
+        fputs("Could not allocate memory for syscall table.", stderr);
+        exit(1);
+    }
+    syscall_table[0] = sys_read;
+    syscall_table[1] = sys_write;
+    syscall_table[2] = sys_open;
+    syscall_table[3] = sys_close;
+    syscall_table[8] = sys_lseek;
+    syscall_table[12] = sys_brk;
+    syscall_table[21] = sys_access;
+    syscall_table[57] = sys_fork;
+    syscall_table[59] = sys_execve;
+    syscall_table[60] = sys_exit;
+    syscall_table[61] = sys_wait4;
+    syscall_table[63] = sys_uname;
+    syscall_table[79] = sys_getcwd;
+    syscall_table[80] = sys_chdir;
+    syscall_table[81] = sys_fchdir;
+    syscall_table[83] = sys_mkdir;
+    syscall_table[87] = sys_unlink;
+    syscall_table[161] = sys_chroot;
+}
+
+void wrmsr(unsigned msr, int low, int high)
+{
+    asm("lea_rcx,[rbp+DWORD] %-8"
+        "mov_rcx,[rcx]"
+        "lea_rax,[rbp+DWORD] %-16"
+        "mov_rax,[rax]"
+        "lea_rdx,[rbp+DWORD] %-24"
+        "mov_rdx,[rdx]"
+        "wrmsr"
+    );
+}
+
+void wrmsrl(unsigned msr, long value)
+{
+    wrmsr(msr, value && 0xFFFFFFFF, value >> 32);
+}
+
+ulong rdmsrl(unsigned msr)
+{
+    asm("lea_rcx,[rbp+DWORD] %-8"
+        "mov_rcx,[rcx]"
+        "rdmsr"
+        "shr_rdx, !20"
+        "add_rax,rdx"
+    );
+}
+
+void _entry_syscall(long syscall, long arg1, long arg2, long arg3, long arg4, long arg5, long arg6)
+{
+    FUNCTION process_syscall = syscall_table[syscall];
+    if (process_syscall != NULL) {
+        return process_syscall(arg1, arg2, arg3, arg4, arg5, arg6);
+    }
+    /* Unsupported syscall */
+    return 0;
+}
+
+void entry_syscall()
+{
+    /* Fix SS register */
+    asm("push_rax"
+        "mov_rax, %0x30"
+        "mov_ss,eax"
+        "pop_rax"
+    );
+    /* Save registers */
+    asm("push_rcx"
+        "push_rbx"
+        "push_rbp"
+        "push_r12"
+        "push_r13"
+        "push_r14"
+        "push_r15"
+    );
+    asm("mov_rbp,rsp"
+        "push_rax"
+        "push_rdi"
+        "push_rsi"
+        "push_rdx"
+        "push_r10"
+        "push_r8"
+        "push_r9"
+        "call %FUNCTION__entry_syscall"
+        "pop_r9"
+        "pop_r8"
+        "pop_r10"
+        "pop_rdx"
+        "pop_rsi"
+        "pop_rdi"
+        "pop_rbx" /* rax is return code, do not overwrite it */
+    );
+    /* Restore registers */
+    asm("pop_r15"
+        "pop_r14"
+        "pop_r13"
+        "pop_r12"
+        "pop_rbp"
+        "pop_rbx"
+        "pop_rcx"
+    );
+    /* Jump back to POSIX program */
+    asm("jmp_rcx");
+}
+
+int main(int argc, char** argv, char** envp)
+{
+    if (argc < 2) {
+        fputs("Usage: ", stderr);
+        fputs(argv[0], stderr);
+        fputs(" <elf file> [arguments]\n", stderr);
+        exit(1);
+    }
+
+    FILE* file_in = fopen(argv[1], "r");
+    if (file_in == NULL) {
+        fputs("Error opening input file.\n", stderr);
+        exit(2);
+    }
+
+    current_process = calloc(1, sizeof(struct process));
+    if (current_process == NULL) {
+        fputs("Could not allocate memory for current process metadata.", stderr);
+        exit(3);
+    }
+    init_io();
+
+    _brk = calloc(1, MAX_MEMORY_PER_PROC);
+    if (_brk == NULL) {
+        fputs("Could not allocate memory for brk area.", stderr);
+        exit(4);
+    }
+
+    /* Load binary into memory */
+    int rval = load_elf(file_in, current_process);
+    if (rval == 1) {
+        fputs("ELF magic header was not found.\n", stderr);
+        exit(5);
+    }
+
+    current_process->entry_point = entry_point(current_process->program.address);
+
+    ulong msr_efer = rdmsrl(MSR_EFER);
+    msr_efer |= 1; /* Enable syscalls */
+
+    ulong msr_star = rdmsrl(MSR_STAR);
+    msr_star |= 0x38 << 32;
+    wrmsrl(MSR_STAR, msr_star);
+    wrmsrl(MSR_EFER, msr_efer);
+    wrmsrl(MSR_LSTAR, entry_syscall);
+
+    init_syscalls();
+    int argc0 = 1; /* skip argv[0] since it contains the name of efi binary */
+    jump(current_process->entry_point, argc, argc0, argv, envp);
+
+    return 1;
+}