add -M flag

README.md

@@ -25,6 +25,7 @@ docker run --rm -v $PWD:/workspace liberize/ssc:latest -s test.sh test
 * g++, perl, binutils
 * libc-dev, libstdc++-dev (only required by -s flag)
 * libz-dev (only required by -E flag)
+* libz-dev, libfuse-dev, git, gcc, make, automake, autoconf, pkg-config, libtool, squashfs-tools (only required by -M flag)
 
 </p>
 </details>
@@ -36,6 +37,7 @@ docker run --rm -v $PWD:/workspace liberize/ssc:latest -s test.sh test
 * g++, perl, binutils
 * glibc-static, libstdc++-static (only required by -s flag)
 * zlib-devel (only required by -E flag)
+* zlib-devel, fuse-devel, git, gcc, make, automake, autoconf, pkgconfig, libtool, squashfs-tools (only required by -M flag)
 
 </p>
 </details>
@@ -86,7 +88,7 @@ docker run --rm -v $PWD:/workspace liberize/ssc:latest -s test.sh test
 More options
 
 ```
-Usage: ./ssc [-4] [-u] [-s] [-r] [-e|-E file] [-0] <script> <binary>
+Usage: ./ssc [-4] [-u] [-s] [-r] [-e|-E|-M file] [-0] [-d date] [-m msg] <script> <binary>
   -u, --untraceable        make untraceable binary
                            enable debugger detection, abort program when debugger is found
   -s, --static             make static binary
@@ -99,6 +101,8 @@ Usage: ./ssc [-4] [-u] [-s] [-r] [-e|-E file] [-0] <script> <binary>
                            the interpreter will be used no matter what shebang is
   -E, --embed-archive      embed specified tar.gz archive into binary, require zlib
                            set relative path in shebang to use an interpreter in the archive
+  -M, --mount-squashfs     append specified gzipped squashfs to binary and mount it at runtime
+                           linux only, works like AppImage. may specify a directory
   -0, --fix-argv0          try to fix $0, may not work
                            if it doesn't work or causes problems, use $SSC_ARGV0 instead
   -d, --expire-date        expire date, for example, 11/30/2023
@@ -130,6 +134,7 @@ Usage: ./ssc [-4] [-u] [-s] [-r] [-e|-E file] [-0] <script> <binary>
 3. [Call a bundled interpreter.](https://github.com/liberize/ssc/tree/master/examples/3_bundle_interpreter)
 4. [Embed an interpreter into the binary.](https://github.com/liberize/ssc/tree/master/examples/4_embed_interpreter)
 5. [Embed an archive into the binary.](https://github.com/liberize/ssc/tree/master/examples/5_embed_archive)
+6. [Embed a squashfs file and mount it at runtime.](https://github.com/liberize/ssc/tree/master/examples/6_mount_squashfs)
 
 ## Builtin variables
 
@@ -139,6 +144,7 @@ The following builtin variables are available to the script (including shebang):
 * `SSC_EXECUTABLE_PATH`: current executable path
 * `SSC_ARGV0`: first command line argument (i.e. $0)
 * `SSC_EXTRACT_DIR`: temporary extraction directory for embeded file, if -e or -E flag is used
+* `SSC_MOUNT_DIR`: temporary mount directory for squashfs, if -M flag is used
 
 ## Interpreter selection
 
@@ -154,6 +160,8 @@ If the binary is generated with `-e`, the interpreter is built into the binary.
 
 If the binary is generated with `-E`, the archive is built into the binary. Upon execution, the archive will be decompressed and extracted to /tmp/ssc/XXXXXX/ with permissions perserved. If the script has a relative-path shebang, the interpreter of the path relative to the extraction directory will be used, otherwise, a system intepreter will be used.
 
+If the binary is generated with `-M`, the squashfs file is appended to the binary. Upon execution, the squashfs file will be mounted to /tmp/ssc/XXXXXX/. If the script has a relative-path shebang, the interpreter of the path relative to the mount directory will be used, otherwise, a system intepreter will be used.
+
 ## Cross compiling
 
 Set `CROSS_COMPILE` variable just like using Makefile.

examples/5_embed_archive/README.md

@@ -4,7 +4,7 @@ We can even embed an archive into our binary, and make a self-extracting depende
 
 To embed an archive, use `-E` flag. The archive may or may not contain an interpreter.
 
-The interpreter will be extracted to /tmp/ssc/XXXXXX, and be deleted after script execution. You may delete it like this at beginning of your script to avoid exposure of the interpreter:
+The archive will be extracted to /tmp/ssc/XXXXXX, and be deleted after script execution. You may delete it like this at beginning of your script to avoid exposure of the interpreter:
 
 ```bash
 rm -rf "$SSC_EXTRACT_DIR"
@@ -25,7 +25,7 @@ rm -rf python/lib/{*tcl*,thread*,Tix*,tk*}
 tar -zcvf cpython.tar.gz python
 rm -rf python
 
-# use -s flag to make our binary static too
+# use -s flag to make our binary static
 ../../ssc ./test_python.sh binary -s -E cpython.tar.gz
 
 # test it

examples/6_mount_squashfs/README.md

@@ -0,0 +1,27 @@
+# Embed a squashfs file and mount it at runtime
+
+Another way to pack some data into the binary and make a dependency-free executable. Same method is used by AppImage. Currently only availble on Linux.
+
+To embed a squashfs file, use `-M` flag.
+
+The squashfs file is directly appended to the binary, upon execution it will be mounted to /tmp/ssc/XXXXXX. This method doesn't extract files, so it should be faster than `-E` flag.
+
+## Example: python
+
+We can embed a whole python package to our binary.
+
+```bash
+# download standalone python
+wget https://github.com/indygreg/python-build-standalone/releases/download/20240814/cpython-3.10.14+20240814-x86_64-unknown-linux-gnu-install_only_stripped.tar.gz -O cpython.tar.gz
+
+# delete redundant files in the archive to make extraction faster
+tar -zxvf cpython.tar.gz
+rm -rf python/include python/share python/lib/pkgconfig python/bin/{2to3*,idle*,pip*,pydoc*,*-config}
+rm -rf python/lib/{*tcl*,thread*,Tix*,tk*}
+
+# use -s flag to make our binary static
+../../ssc ./test_python.sh binary -s -M python
+
+# test it
+./binary
+```

examples/6_mount_squashfs/test_python.sh

@@ -0,0 +1,9 @@
+#! PYTHONHOME=$SSC_MOUNT_DIR ./bin/python3
+# use environment variables just like in shell
+
+import os
+import sys
+import shutil
+
+print(os.environ)
+print(sys.argv)

src/elf.h

@@ -0,0 +1,108 @@
+/* 
+ * 
+ *  Linux kernel
+ *  Copyright (C) 2017 Linus Torvalds
+ *  Modified work Copyright (C) 2017 @teras (https://github.com/teras)
+ *  (Shortened version -- original work found here:
+ *   https://github.com/torvalds/linux/blob/master/include/uapi/linux/elf.h)
+ *
+ *  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 2 of the License.
+ *
+ *  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, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ */
+
+#ifndef LIGHT_ELF_H
+#define LIGHT_ELF_H
+
+#include <inttypes.h>
+
+typedef uint16_t Elf32_Half;
+typedef uint16_t Elf64_Half;
+typedef uint32_t Elf32_Word;
+typedef uint32_t Elf64_Word;
+typedef uint64_t Elf64_Xword;
+typedef uint32_t Elf32_Addr;
+typedef uint64_t Elf64_Addr;
+typedef uint32_t Elf32_Off;
+typedef uint64_t Elf64_Off;
+
+#define EI_NIDENT 16
+
+typedef struct elf32_hdr {
+    unsigned char e_ident[EI_NIDENT];
+    Elf32_Half e_type;
+    Elf32_Half e_machine;
+    Elf32_Word e_version;
+    Elf32_Addr e_entry; /* Entry point */
+    Elf32_Off e_phoff;
+    Elf32_Off e_shoff;
+    Elf32_Word e_flags;
+    Elf32_Half e_ehsize;
+    Elf32_Half e_phentsize;
+    Elf32_Half e_phnum;
+    Elf32_Half e_shentsize;
+    Elf32_Half e_shnum;
+    Elf32_Half e_shstrndx;
+} Elf32_Ehdr;
+
+typedef struct elf64_hdr {
+    unsigned char e_ident[EI_NIDENT]; /* ELF "magic number" */
+    Elf64_Half e_type;
+    Elf64_Half e_machine;
+    Elf64_Word e_version;
+    Elf64_Addr e_entry; /* Entry point virtual address */
+    Elf64_Off e_phoff; /* Program header table file offset */
+    Elf64_Off e_shoff; /* Section header table file offset */
+    Elf64_Word e_flags;
+    Elf64_Half e_ehsize;
+    Elf64_Half e_phentsize;
+    Elf64_Half e_phnum;
+    Elf64_Half e_shentsize;
+    Elf64_Half e_shnum;
+    Elf64_Half e_shstrndx;
+} Elf64_Ehdr;
+
+typedef struct elf32_shdr {
+    Elf32_Word sh_name;
+    Elf32_Word sh_type;
+    Elf32_Word sh_flags;
+    Elf32_Addr sh_addr;
+    Elf32_Off sh_offset;
+    Elf32_Word sh_size;
+    Elf32_Word sh_link;
+    Elf32_Word sh_info;
+    Elf32_Word sh_addralign;
+    Elf32_Word sh_entsize;
+} Elf32_Shdr;
+
+typedef struct elf64_shdr {
+    Elf64_Word sh_name; /* Section name, index in string tbl */
+    Elf64_Word sh_type; /* Type of section */
+    Elf64_Xword sh_flags; /* Miscellaneous section attributes */
+    Elf64_Addr sh_addr; /* Section virtual addr at execution */
+    Elf64_Off sh_offset; /* Section file offset */
+    Elf64_Xword sh_size; /* Size of section in bytes */
+    Elf64_Word sh_link; /* Index of another section */
+    Elf64_Word sh_info; /* Additional section information */
+    Elf64_Xword sh_addralign; /* Section alignment */
+    Elf64_Xword sh_entsize; /* Entry size if section holds table */
+} Elf64_Shdr;
+
+#define ELFCLASS32  1
+#define ELFDATA2LSB 1
+#define ELFDATA2MSB 2
+#define ELFCLASS64  2
+#define EI_CLASS    4
+#define EI_DATA     5
+
+#endif /* elf.h */

src/main.cpp

@@ -25,6 +25,9 @@
 #if defined(EMBED_INTERPRETER_NAME) || defined(EMBED_ARCHIVE) || defined(RC4_KEY)
 #include "embed.h"
 #endif
+#ifdef MOUNT_SQUASHFS
+#include "mount.h"
+#endif
 #ifdef RC4_KEY
 #include "rc4.h"
 #endif
@@ -58,7 +61,7 @@ int main(int argc, char* argv[]) {
 #endif
 
     std::string exe_path = get_exe_path(), base_dir = dir_name(exe_path);
-    std::string interpreter_path, extract_dir;
+    std::string interpreter_path, extract_dir, mount_dir;
 
 #if defined(INTERPRETER)
     interpreter_path = OBF(STR(INTERPRETER));
@@ -70,8 +73,11 @@ int main(int argc, char* argv[]) {
 #elif defined(EMBED_ARCHIVE)
     base_dir = extract_dir = extract_embeded_file();
     atexit(remove_extract_dir);
+#elif defined(MOUNT_SQUASHFS)
+    base_dir = mount_dir = mount_squashfs();
 #endif
     setenv(OBF("SSC_EXTRACT_DIR"), extract_dir.c_str(), 1);
+    setenv(OBF("SSC_MOUNT_DIR"), mount_dir.c_str(), 1);
     setenv(OBF("SSC_EXECUTABLE_PATH"), exe_path.c_str(), 1);
     setenv(OBF("SSC_ARGV0"), argv[0], 1);