├── .dockerignore
├── .gitmodules
├── docker-compose.yaml
├── .gitignore
├── shell.nix
├── .envrc
├── bin
    └── genkey
├── Dockerfile
├── maple
    ├── gemini.hh
    ├── maple.hh
    ├── titan.hh
    ├── gemini.cc
    ├── titan.cc
    └── maple.cc
├── Tupfile
├── flake.lock
├── flake.nix
├── README.md
└── LICENSE


/.dockerignore:
--------------------------------------------------------------------------------
1 | # Ignore everything
2 | **
3 | 
4 | !maple
5 | !build.ninja
6 | 
7 | 


--------------------------------------------------------------------------------
/.gitmodules:
--------------------------------------------------------------------------------
1 | [submodule ".maple/gmi"]
2 | 	path = .maple/gmi
3 | 	url = https://github.com/gemrest/gem.rest
4 | 


--------------------------------------------------------------------------------
/docker-compose.yaml:
--------------------------------------------------------------------------------
1 | services:
2 |   maple:
3 |     ports:
4 |       - "1965:1965"
5 |     volumes:
6 |       - "./.maple:/maple/.maple"
7 |     image: "fuwn/maple:latest"
8 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
 1 | # Development
 2 | *.pem
 3 | 
 4 | # IDE
 5 | .idea
 6 | .vscode
 7 | 
 8 | # Tup
 9 | .tup
10 | 
11 | # Build Artifacts
12 | build
13 | 
14 | # Ninja
15 | .ninja_log
16 | 
17 | # Nix
18 | result
19 | 


--------------------------------------------------------------------------------
/shell.nix:
--------------------------------------------------------------------------------
 1 | {
 2 |   pkgs ? import <nixpkgs> { },
 3 | }:
 4 | pkgs.mkShell {
 5 |   buildInputs = with pkgs; [
 6 |     libressl_3_9
 7 |     ninja
 8 |     clang_19
 9 |     (llvmPackages_19.clang-tools.override { enableLibcxx = true; })
10 |   ];
11 | }
12 | 


--------------------------------------------------------------------------------
/.envrc:
--------------------------------------------------------------------------------
 1 | #!/usr/bin/env bash
 2 | 
 3 | if type -P lorri &>/dev/null; then
 4 |   eval "$(lorri direnv)"
 5 | else
 6 |   echo 'while direnv evaluated .envrc, could not find the command "lorri" [https://github.com/nix-community/lorri]'
 7 | 
 8 |   use flake
 9 | fi
10 | 


--------------------------------------------------------------------------------
/bin/genkey:
--------------------------------------------------------------------------------
 1 | #!/usr/bin/env bash
 2 | 
 3 | read \
 4 |   -rp \
 5 |   "Which common name (hostname) would you like to use for the generated key? " \
 6 |   common_name
 7 | 
 8 | openssl req \
 9 |   -new \
10 |   -subj "/CN=$common_name" \
11 |   -x509 \
12 |   -newkey ec \
13 |   -pkeyopt ec_paramgen_curve:prime256v1 \
14 |   -days 365 \
15 |   -nodes \
16 |   -out .maple/public.pem \
17 |   -keyout .maple/private.pem \
18 |   -inform pem
19 | 


--------------------------------------------------------------------------------
/Dockerfile:
--------------------------------------------------------------------------------
 1 | FROM alpine:latest as environment
 2 | 
 3 | RUN apk update \
 4 |   && apk upgrade \
 5 |   && apk add --no-cache libstdc++
 6 | 
 7 | FROM environment as build_environment
 8 | 
 9 | RUN apk add --no-cache \
10 |   clang \
11 |   ninja \
12 |   alpine-sdk \
13 |   openssl-dev \
14 |   linux-headers
15 | 
16 | FROM build_environment as builder
17 | 
18 | WORKDIR /maple
19 | 
20 | COPY ./ ./
21 | 
22 | RUN ninja
23 | 
24 | FROM environment
25 | 
26 | WORKDIR /maple
27 | 
28 | COPY --from=builder /maple/build/maple ./
29 | 
30 | EXPOSE 1965
31 | 
32 | ENTRYPOINT ["./maple"]
33 | 


--------------------------------------------------------------------------------
/maple/gemini.hh:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
 3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 4 |  *
 5 |  * This program is free software: you can redistribute it and/or modify
 6 |  * it under the terms of the GNU General Public License as published by
 7 |  * the Free Software Foundation, version 3.
 8 |  *
 9 |  * This program is distributed in the hope that it will be useful, but
10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 |  * General Public License for more details.
13 |  *
14 |  * You should have received a copy of the GNU General Public License
15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 |  *
17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
18 |  * SPDX-License-Identifier: GPL-3.0-only
19 |  */
20 | 
21 | #ifndef GEMINI_HH
22 | #define GEMINI_HH
23 | 
24 | #include <sstream>
25 | #include <vector>
26 | 
27 | namespace maple {
28 | namespace gemini {
29 | auto handle_client(const std::vector<std::string> &, std::string,
30 |                    std::stringstream &) -> void;
31 | }
32 | } // namespace maple
33 | 
34 | #endif // GEMINI_HH
35 | 


--------------------------------------------------------------------------------
/Tupfile:
--------------------------------------------------------------------------------
 1 | NAME = maple
 2 | 
 3 | # Input & Output Directories
 4 | SOURCE_DIRECTORY = $(NAME)
 5 | INCLUDE_DIRECTORY = $(NAME)
 6 | BUILD_DIRECTORY = build
 7 | 
 8 | # Compiler Configuration
 9 | CXX = clang++
10 | CXX_EXTENSION = cc
11 | CXX_FLAGS = -std=c++23 -I $(INCLUDE_DIRECTORY) -Weverything -Wno-padded -Wno-c++98-compat -MMD -Wno-c++98-compat-pedantic
12 | LD_FLAGS = -lssl -lcrypto
13 | 
14 | # Clang-Tidy Configuration
15 | CLANG_TIDY_CHECKS = '-*,bugprone-*,clang-analyzer-*,concurrency-*,cppcoreguildelines-*,llvm-*,misc-*,modernize-*,performance-*,portability-*,readability-*,-readability-function-cognitive-complexity,-bugprone-easily-swappable-parameters,-concurrency-mt-unsafe'
16 | CLANG_TIDY_FLAGS = -checks=$(CLANG_TIDY_CHECKS) -warnings-as-errors=* -quiet
17 | 
18 | # : foreach $(SOURCE_DIRECTORY)/*.$(CXX_EXTENSION) $(INCLUDE_DIRECTORY)/*.hh |> clang-format -i -style=LLVM %f |>
19 | : foreach $(SOURCE_DIRECTORY)/*.$(CXX_EXTENSION) |> clang-tidy $(CLANG_TIDY_FLAGS) %f  -- $(CXX_FLAGS) |>
20 | : foreach $(SOURCE_DIRECTORY)/*.$(CXX_EXTENSION) |> ^j^ $(CXX) $(CXX_FLAGS) -MF $(BUILD_DIRECTORY)/%B.d -c %f -o %o |> $(BUILD_DIRECTORY)/%B.o | $(BUILD_DIRECTORY)/%B.d
21 | : $(BUILD_DIRECTORY)/*.o |> $(CXX) $(LD_FLAGS) %f -o %o |> $(BUILD_DIRECTORY)/$(NAME)
22 | 
23 | 


--------------------------------------------------------------------------------
/maple/maple.hh:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
 3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 4 |  *
 5 |  * This program is free software: you can redistribute it and/or modify
 6 |  * it under the terms of the GNU General Public License as published by
 7 |  * the Free Software Foundation, version 3.
 8 |  *
 9 |  * This program is distributed in the hope that it will be useful, but
10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 |  * General Public License for more details.
13 |  *
14 |  * You should have received a copy of the GNU General Public License
15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 |  *
17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
18 |  * SPDX-License-Identifier: GPL-3.0-only
19 |  */
20 | 
21 | #ifndef MAPLE_HH
22 | #define MAPLE_HH
23 | 
24 | #include <openssl/ssl.h>
25 | #include <string>
26 | 
27 | namespace maple {
28 | static int maple_socket;
29 | static SSL_CTX *ssl_context;
30 | 
31 | auto prepare_exit_with(const char *, bool) -> int;
32 | auto setup_environment(bool &, std::string &, std::size_t &) -> int;
33 | auto setup_ssl() -> int;
34 | } // namespace maple
35 | 
36 | #endif // MAPLE_HH
37 | 


--------------------------------------------------------------------------------
/maple/titan.hh:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
 3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 4 |  *
 5 |  * This program is free software: you can redistribute it and/or modify
 6 |  * it under the terms of the GNU General Public License as published by
 7 |  * the Free Software Foundation, version 3.
 8 |  *
 9 |  * This program is distributed in the hope that it will be useful, but
10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 |  * General Public License for more details.
13 |  *
14 |  * You should have received a copy of the GNU General Public License
15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 |  *
17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
18 |  * SPDX-License-Identifier: GPL-3.0-only
19 |  */
20 | 
21 | #ifndef TITAN_HH
22 | #define TITAN_HH
23 | 
24 | #include <map>
25 | #include <sstream>
26 | #include <vector>
27 | 
28 | namespace maple {
29 | namespace titan {
30 | /// Convert a `std::vector` of Titan parameters into a key/ value `std::map`
31 | auto parameters_to_map(const std::vector<std::string> &)
32 |     -> std::map<std::string, std::string>;
33 | 
34 | auto handle_client(std::stringstream &, std::string, const std::string &,
35 |                    std::size_t) -> void;
36 | } // namespace titan
37 | } // namespace maple
38 | 
39 | #endif // TITAN_HH
40 | 


--------------------------------------------------------------------------------
/maple/gemini.cc:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
 3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 4 |  *
 5 |  * This program is free software: you can redistribute it and/or modify
 6 |  * it under the terms of the GNU General Public License as published by
 7 |  * the Free Software Foundation, version 3.
 8 |  *
 9 |  * This program is distributed in the hope that it will be useful, but
10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 |  * General Public License for more details.
13 |  *
14 |  * You should have received a copy of the GNU General Public License
15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 |  *
17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
18 |  * SPDX-License-Identifier: GPL-3.0-only
19 |  */
20 | 
21 | #include <algorithm>
22 | #include <fstream>
23 | #include <iostream>
24 | #include <sstream>
25 | #include <string>
26 | #include <vector>
27 | 
28 | #include "gemini.hh"
29 | 
30 | namespace maple::gemini {
31 | auto handle_client(const std::vector<std::string> &gemini_files,
32 |                    std::string path, std::stringstream &response) -> void {
33 |   // Check if the route is a file being served
34 |   if (std::find(gemini_files.begin(), gemini_files.end(),
35 |                 ".maple/gmi" + path) != gemini_files.end()) {
36 |     // If the route is a file being served; get the file contents
37 |     response << "20 text/gemini\r\n"
38 |              << std::ifstream(".maple/gmi" + path).rdbuf();
39 |   } else {
40 |     if (path.empty() || path.at(path.length() - 1) == '/') {
41 |       response << "20 text/gemini\r\n"
42 |                << std::ifstream(".maple/gmi" + path + "index.gmi").rdbuf();
43 |     } else {
44 |       response
45 |           << "51 The server (Maple) could not find the specified file.\r\n";
46 |     }
47 |   }
48 | 
49 |   std::cout << "requested " << path << '\n';
50 | }
51 | } // namespace maple::gemini
52 | 


--------------------------------------------------------------------------------
/flake.lock:
--------------------------------------------------------------------------------
 1 | {
 2 |   "nodes": {
 3 |     "flake-compat": {
 4 |       "flake": false,
 5 |       "locked": {
 6 |         "lastModified": 1696426674,
 7 |         "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
 8 |         "owner": "edolstra",
 9 |         "repo": "flake-compat",
10 |         "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
11 |         "type": "github"
12 |       },
13 |       "original": {
14 |         "owner": "edolstra",
15 |         "repo": "flake-compat",
16 |         "type": "github"
17 |       }
18 |     },
19 |     "flake-utils": {
20 |       "inputs": {
21 |         "systems": [
22 |           "systems"
23 |         ]
24 |       },
25 |       "locked": {
26 |         "lastModified": 1726560853,
27 |         "narHash": "sha256-X6rJYSESBVr3hBoH0WbKE5KvhPU5bloyZ2L4K60/fPQ=",
28 |         "owner": "numtide",
29 |         "repo": "flake-utils",
30 |         "rev": "c1dfcf08411b08f6b8615f7d8971a2bfa81d5e8a",
31 |         "type": "github"
32 |       },
33 |       "original": {
34 |         "owner": "numtide",
35 |         "repo": "flake-utils",
36 |         "type": "github"
37 |       }
38 |     },
39 |     "nixpkgs": {
40 |       "locked": {
41 |         "lastModified": 1727653192,
42 |         "narHash": "sha256-YBIXvJOLKU1FIQM0fB5lBLT1CoPpMCn03vHyNsVFXZ4=",
43 |         "owner": "NixOS",
44 |         "repo": "nixpkgs",
45 |         "rev": "c6f2346239c6f6abdc8befcb2a10759083c85f5d",
46 |         "type": "github"
47 |       },
48 |       "original": {
49 |         "owner": "NixOS",
50 |         "repo": "nixpkgs",
51 |         "type": "github"
52 |       }
53 |     },
54 |     "root": {
55 |       "inputs": {
56 |         "flake-compat": "flake-compat",
57 |         "flake-utils": "flake-utils",
58 |         "nixpkgs": "nixpkgs",
59 |         "systems": "systems"
60 |       }
61 |     },
62 |     "systems": {
63 |       "locked": {
64 |         "lastModified": 1681028828,
65 |         "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
66 |         "owner": "nix-systems",
67 |         "repo": "default",
68 |         "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
69 |         "type": "github"
70 |       },
71 |       "original": {
72 |         "owner": "nix-systems",
73 |         "repo": "default",
74 |         "type": "github"
75 |       }
76 |     }
77 |   },
78 |   "root": "root",
79 |   "version": 7
80 | }
81 | 


--------------------------------------------------------------------------------
/flake.nix:
--------------------------------------------------------------------------------
 1 | {
 2 |   description = "A very simple static Gemini server, now with Titan support!";
 3 | 
 4 |   inputs = {
 5 |     nixpkgs.url = "github:NixOS/nixpkgs";
 6 |     systems.url = "github:nix-systems/default";
 7 | 
 8 |     flake-compat = {
 9 |       url = "github:edolstra/flake-compat";
10 |       flake = false;
11 |     };
12 | 
13 |     flake-utils = {
14 |       url = "github:numtide/flake-utils";
15 |       inputs.systems.follows = "systems";
16 |     };
17 |   };
18 | 
19 |   outputs =
20 |     {
21 |       nixpkgs,
22 |       flake-utils,
23 |       self,
24 |       ...
25 |     }:
26 |     flake-utils.lib.eachDefaultSystem (
27 |       system:
28 |       let
29 |         pkgs = import nixpkgs { inherit system; };
30 | 
31 |         meta = with pkgs.lib; {
32 |           description = "A very simple static Gemini server, now with Titan support!";
33 |           homepage = "https://github.com/gemrest/maple";
34 |           license = licenses.gpl3Only;
35 |           maintainers = [ maintainers.Fuwn ];
36 |           mainPackage = "maple";
37 |           platforms = platforms.unix;
38 |         };
39 | 
40 |         maple =
41 |           with pkgs;
42 |           (
43 |             if pkgs.stdenv.isDarwin then
44 |               pkgs.clangStdenvNoLibs
45 |             else
46 |               pkgs.stdenvAdapters.useMoldLinker pkgs.clangStdenvNoLibs
47 |           ).mkDerivation
48 |             {
49 |               inherit meta;
50 | 
51 |               name = "maple";
52 |               version = "0.1.6";
53 |               src = lib.cleanSource ./.;
54 | 
55 |               nativeBuildInputs = [
56 |                 ninja
57 |                 clang
58 |               ];
59 | 
60 |               buildInputs = [
61 |                 libressl.dev
62 |               ];
63 | 
64 |               buildPhase = ''
65 |                 mkdir -p $out/bin
66 |                 ninja
67 |               '';
68 | 
69 |               installPhase = ''
70 |                 cp build/maple $out/bin/maple
71 |               '';
72 |             };
73 |       in
74 |       {
75 |         packages = {
76 |           inherit maple;
77 | 
78 |           default = maple;
79 |         };
80 | 
81 |         apps = {
82 |           maple = {
83 |             inherit meta;
84 | 
85 |             type = "app";
86 |             program = "${maple}/bin/maple";
87 |           };
88 | 
89 |           default = self.apps.${system}.maple;
90 |         };
91 | 
92 |         devShells.default = import ./shell.nix {
93 |           inherit pkgs;
94 |         };
95 |       }
96 |     );
97 | }
98 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
  1 | # Maple
  2 | 
  3 | A very simple static Gemini server, now with Titan support!
  4 | 
  5 | ### Lines-of-code
  6 | 
  7 | This codebase is now 351 lines of lines-of-code!
  8 | 
  9 | The statement "... written within a single file and liberally
 10 | spanning 159 lines-of-code." has been removed.
 11 | 
 12 | If you would still like the minimal 159-LOC experience, checkout
 13 | [49ce0f8](https://github.com/gemrest/maple/tree/49ce0f83b8abd1af4760e56c1673c6997ef8a2c4)!
 14 | (Docker tag `0.1.4`) Do note, that version of this project is outdated and only
 15 | has Gemini support.
 16 | 
 17 | ## Usage
 18 | 
 19 | ### Docker Compose
 20 | 
 21 | A Docker Compose file is already setup [here](./docker-compose.yaml). The only
 22 | field which should be modified is the `ports`, if need be.
 23 | 
 24 | ```shell
 25 | docker-compose up -d
 26 | ```
 27 | 
 28 | ### Docker
 29 | 
 30 | ```shell
 31 | docker run -p 1965:1965 -v ./your_capsules_directory:/maple/.maple fuwn/maple:latest
 32 | ```
 33 | 
 34 | ### Executable
 35 | 
 36 | 1. Build: `tup` (requires [Tup](https://gittup.org/tup/index.html))
 37 | 2. Run: `build/maple`, or
 38 |    `TITAN=1 TITAN_TOKEN=secret TITAN_MAX_SIZE=2048 build/maple`
 39 | 
 40 | ### Certificates
 41 | 
 42 | Before any possible method of usage; you must generate or use a preexisting
 43 | server certificate.
 44 | 
 45 | If you do not have an existing certificate, generate one using the provided
 46 | certificate generations script: [`bin/genkey`](bin/genkey) (requires
 47 | [OpenSSL](https://www.openssl.org/)).
 48 | 
 49 | The server certificate must be placed in a directory -- directly adjacent to the
 50 | Docker Compose file or executable -- named [`.maple`](.maple). The public and
 51 | private keys must be named `public.pem` and `private.pem`, respectively.
 52 | 
 53 | ### Gemini Content
 54 | 
 55 | Gemini content must be placed in a directory -- directly adjacent to the
 56 | Docker Compose file or executable -- named [`.maple/gmi`](.maple/gmi) and
 57 | ending with the file extension `.gmi`.
 58 | 
 59 | ### Environment Variables
 60 | 
 61 | Maple can be configured with three optional environment variables:
 62 | 
 63 | #### `TITAN`
 64 | 
 65 | Enable Titan support.
 66 | 
 67 | Takes a value of either `true` or `1`, case-insensitive.
 68 | 
 69 | Defaults to off.
 70 | 
 71 | #### `TITAN_TOKEN`
 72 | 
 73 | Set a token to restrict Titan access.
 74 | 
 75 | Takes a string value, case-sensitive.
 76 | 
 77 | Defaults to no token, **anyone can upload!**
 78 | 
 79 | #### `TITAN_MAX_SIZE`
 80 | 
 81 | The maximum size in bytes which a Titan upload is permitted to perform.
 82 | 
 83 | Takes an integer.
 84 | 
 85 | Default to `1024`.
 86 | 
 87 | ### Hacking
 88 | 
 89 | If you decide to tamper with Maple, you should give your commits a test. As
 90 | there isn't a test suite yet, feel free to use any of these examples:
 91 | 
 92 | ```bash
 93 | # Using OpenSSL directly to debug different requests:
 94 | $ openssl s_client -ign_eof -quiet -connect localhost:1965 <<< \
 95 | > "gemini://localhost:1965"
 96 | 
 97 | # Using Bollux to debug proper requests... or any client!
 98 | $ bollux localhost
 99 | ```
100 | 
101 | ## Capsules using Maple
102 | 
103 | [Add yours!](https://github.com/gemrest/maple/edit/main/README.md)
104 | 
105 | - <gemini://gem.rest/> (<https://gem.rest/>)
106 | 
107 | ## License
108 | 
109 | This project is licensed with the [GNU General Public License v3.0](./LICENSE).
110 | 


--------------------------------------------------------------------------------
/maple/titan.cc:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
  3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
  4 |  *
  5 |  * This program is free software: you can redistribute it and/or modify
  6 |  * it under the terms of the GNU General Public License as published by
  7 |  * the Free Software Foundation, version 3.
  8 |  *
  9 |  * This program is distributed in the hope that it will be useful, but
 10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
 11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 12 |  * General Public License for more details.
 13 |  *
 14 |  * You should have received a copy of the GNU General Public License
 15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
 16 |  *
 17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 18 |  * SPDX-License-Identifier: GPL-3.0-only
 19 |  */
 20 | 
 21 | #include <cstddef>
 22 | #include <fstream>
 23 | #include <map>
 24 | #include <sstream>
 25 | #include <string>
 26 | #include <vector>
 27 | 
 28 | #include "titan.hh"
 29 | 
 30 | namespace maple::titan {
 31 | auto parameters_to_map(const std::vector<std::string> &parameters)
 32 |     -> std::map<std::string, std::string> {
 33 |   std::map<std::string, std::string> parameters_map;
 34 | 
 35 |   for (const auto &parameter : parameters) {
 36 |     // Find the key in `parameter`
 37 |     const std::size_t parameter_delimiter_position = parameter.find('=');
 38 | 
 39 |     if (parameter_delimiter_position == std::string::npos) {
 40 |       continue;
 41 |     }
 42 | 
 43 |     const std::string key = parameter.substr(0, parameter_delimiter_position);
 44 |     const std::string value =
 45 |         parameter.substr(parameter_delimiter_position + 1);
 46 | 
 47 |     // Add the key and value to `parameters_map`
 48 |     parameters_map.emplace(key, value);
 49 |   }
 50 | 
 51 |   return parameters_map;
 52 | }
 53 | 
 54 | auto handle_client(std::stringstream &response, std::string path,
 55 |                    const std::string &titan_token, std::size_t titan_max_size)
 56 |     -> void {
 57 |   std::vector<std::string> parameters;
 58 |   // Find path in `path`
 59 |   std::size_t delimiter_position = path.find(';');
 60 |   std::string update_path = path.substr(0, delimiter_position);
 61 |   const std::string body = path.substr(path.find('\n') + 1, path.length() - 1);
 62 | 
 63 |   path.erase(path.find('\n') - 1, path.length() - 1);
 64 |   // parameters.push_back(update_path);
 65 |   path.erase(0, delimiter_position + 1); // Remove path from `path`
 66 | 
 67 |   // Find mime parameter in `path`
 68 |   delimiter_position = path.find(';');
 69 | 
 70 |   parameters.push_back(path.substr(0, delimiter_position));
 71 |   path.erase(0, delimiter_position + 1); // Remove mime parameter from `path`
 72 | 
 73 |   // Find size parameter in `path`
 74 |   delimiter_position = path.find(';');
 75 | 
 76 |   parameters.push_back(path.substr(0, delimiter_position));
 77 | 
 78 |   // Find token parameter in `path`
 79 |   delimiter_position = path.find(';');
 80 | 
 81 |   // Since the token is optional, only get and assign the token
 82 |   // parameters value if it exists.
 83 |   if (delimiter_position != std::string::npos) {
 84 |     parameters.push_back(
 85 |         path.substr(delimiter_position + 1, path.length() - 1));
 86 |   }
 87 | 
 88 |   /// Check if a parameter exists within a `std::vector` of Titan
 89 |   /// parameters.
 90 |   /* auto parameter_exists = [](
 91 |     const std::vector<std::string> &_parameters,
 92 |     const std::string &parameter
 93 |   ) -> bool {
 94 |     return std::any_of(
 95 |       _parameters.begin(),
 96 |       _parameters.end(),
 97 |       [&](const std::string &s) -> bool {
 98 |         return s.find(parameter) != std::string::npos;
 99 |       }
100 |     );
101 |   }; */
102 | 
103 |   std::map<std::string, std::string> parameters_map =
104 |       maple::titan::parameters_to_map(parameters);
105 | 
106 |   // Make sure all tokens have been supplied
107 |   for (;;) {
108 |     if (parameters_map.find("mime") == parameters_map.end()) {
109 |       response << "20 text/gemini\r\nThe serve (Maple) did not "
110 |                   "receive a mime parameter!";
111 |       break;
112 |     }
113 | 
114 |     if (parameters_map.find("size") == parameters_map.end()) {
115 |       response << "20 text/gemini\r\nThe serve (Maple) did not "
116 |                   "receive a size parameter!";
117 | 
118 |       break;
119 |     }
120 | 
121 |     if (!titan_token.empty() &&
122 |         parameters_map.find("token") == parameters_map.end()) {
123 |       response << "20 text/gemini\r\nThe serve (Maple) did not "
124 |                   "receive a token parameter!";
125 | 
126 |       break;
127 |     }
128 | 
129 |     try {
130 |       const std::size_t body_size =
131 |           static_cast<std::size_t>(std::stoi(parameters_map.at("size")));
132 | 
133 |       if (body_size > titan_max_size) {
134 |         response << "20 text/gemini\r\nThe server (Maple) received a body "
135 |                  << "which is larger than the maximum allowed body size ("
136 |                  << titan_max_size << ").";
137 | 
138 |         break;
139 |       }
140 |     } catch (...) {
141 |       response << "20 text/gemini\r\nThe server (Maple) could not interpret "
142 |                   "the size parameter as an integer!";
143 | 
144 |       break;
145 |     }
146 | 
147 |     if (update_path == "/") {
148 |       update_path = "/index.gmi";
149 |     }
150 | 
151 |     const auto token_iterator = parameters_map.find("token");
152 |     const std::string token =
153 |         token_iterator == parameters_map.end() ? "" : token_iterator->second;
154 | 
155 |     if (token == titan_token) {
156 |       std::ofstream file(".maple/gmi" + update_path);
157 | 
158 |       file << body;
159 | 
160 |       response << "20 text/gemini\r\nSuccessfully wrote " << body.length()
161 |                << " bytes to " << update_path << '!';
162 |     } else {
163 |       response << "20 text/gemini\r\nThe server (Maple) wrote to "
164 |                << update_path;
165 |     }
166 | 
167 |     break;
168 |   }
169 | }
170 | } // namespace maple::titan
171 | 


--------------------------------------------------------------------------------
/maple/maple.cc:
--------------------------------------------------------------------------------
  1 | /*
  2 |  * This file is part of Maple <https://github.com/gemrest/maple>.
  3 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
  4 |  *
  5 |  * This program is free software: you can redistribute it and/or modify
  6 |  * it under the terms of the GNU General Public License as published by
  7 |  * the Free Software Foundation, version 3.
  8 |  *
  9 |  * This program is distributed in the hope that it will be useful, but
 10 |  * WITHOUT ANY WARRANTY; without even the implied warranty of
 11 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 12 |  * General Public License for more details.
 13 |  *
 14 |  * You should have received a copy of the GNU General Public License
 15 |  * along with this program. If not, see <http://www.gnu.org/licenses/>.
 16 |  *
 17 |  * Copyright (C) 2022-2022 Fuwn <contact@fuwn.me>
 18 |  * SPDX-License-Identifier: GPL-3.0-only
 19 |  */
 20 | 
 21 | #include <algorithm>
 22 | #include <array>
 23 | #include <cctype>
 24 | #include <csignal>
 25 | #include <cstddef>
 26 | #include <cstdio>
 27 | #include <cstdlib>
 28 | #include <filesystem>
 29 | #include <iostream>
 30 | #include <netinet/in.h>
 31 | #include <openssl/err.h>
 32 | #include <openssl/ssl.h>
 33 | #include <sstream>
 34 | #include <string>
 35 | #include <sys/socket.h>
 36 | #include <unistd.h>
 37 | #include <vector>
 38 | 
 39 | #if !defined(__APPLE__)
 40 | #include <asm-generic/socket.h>
 41 | #endif
 42 | 
 43 | #include "gemini.hh"
 44 | #include "maple.hh"
 45 | #include "titan.hh"
 46 | 
 47 | auto main() -> int {
 48 |   std::vector<std::string> gemini_files;
 49 |   bool titan = false;
 50 |   std::string titan_token;
 51 |   std::size_t titan_max_size = 0;
 52 |   const std::string GEMINI_FILE_EXTENSION = "gmi";
 53 | 
 54 |   // Check if the user is want to support Titan and set it up
 55 |   if (maple::setup_environment(titan, titan_token, titan_max_size) == 1) {
 56 |     return EXIT_FAILURE;
 57 |   }
 58 | 
 59 |   // Try a graceful shutdown when a SIGINT is detected
 60 |   signal(SIGINT, [](int _signal) -> void {
 61 |     std::cout << "shutdown(" << _signal << ")\n";
 62 | 
 63 |     close(maple::maple_socket);
 64 |     SSL_CTX_free(maple::ssl_context);
 65 |   });
 66 |   signal(SIGPIPE, SIG_IGN);
 67 | 
 68 |   // Find and keep track of all Gemini files to serve
 69 |   for (const std::filesystem::directory_entry &entry :
 70 |        std::filesystem::recursive_directory_iterator(".maple/gmi")) {
 71 |     std::string file_extension = entry.path().string().substr(
 72 |         entry.path().string().find_last_of('.') + 1);
 73 | 
 74 |     // Only keep track of file if it is a Gemini file
 75 |     if (std::equal(file_extension.begin(), file_extension.end(),
 76 |                    GEMINI_FILE_EXTENSION.begin(), GEMINI_FILE_EXTENSION.end(),
 77 |                    [](char character_a, char character_b) -> bool {
 78 |                      return std::tolower(character_a) ==
 79 |                             std::tolower(character_b);
 80 |                    })) {
 81 |       gemini_files.push_back(entry.path());
 82 |     }
 83 |   }
 84 | 
 85 |   // Inform user of which files will be served
 86 |   for (const std::string &file : gemini_files) {
 87 |     std::cout << "serving " << file << '\n';
 88 |   }
 89 | 
 90 |   // Setup SSL
 91 |   if (maple::setup_ssl() == EXIT_FAILURE) {
 92 |     return EXIT_FAILURE;
 93 |   }
 94 | 
 95 |   // Listen and serve connections
 96 |   for (;;) {
 97 |     sockaddr_in socket_address_{};
 98 |     unsigned int socket_address_length = sizeof(socket_address_);
 99 |     SSL *ssl;
100 |     const int client = accept(maple::maple_socket,
101 |                               reinterpret_cast<sockaddr *>(&socket_address_),
102 |                               &socket_address_length);
103 | 
104 |     if (client < 0) {
105 |       return maple::prepare_exit_with("unable to accept", false);
106 |     }
107 | 
108 |     ssl = SSL_new(maple::ssl_context);
109 | 
110 |     SSL_set_fd(ssl, client);
111 | 
112 |     if (SSL_accept(ssl) <= 0) {
113 |       ERR_print_errors_fp(stderr);
114 |     } else {
115 |       std::stringstream response;
116 |       std::size_t index_of_junk;
117 |       int request_scheme; // Gemini = 1, Titan = 2, Error = 0
118 |       std::size_t bytes_read = 0;
119 |       constexpr std::size_t GEMINI_MAXIMUM_REQUEST_SIZE = 1024;
120 |       std::array<char, GEMINI_MAXIMUM_REQUEST_SIZE> request{};
121 |       const int read_result =
122 |           SSL_read_ex(ssl, request.begin(), request.size(), &bytes_read);
123 | 
124 |       if (read_result > 0 && bytes_read > 0) {
125 |         std::string path(request.data(), bytes_read);
126 | 
127 |         if (path.starts_with("gemini://")) {
128 |           request_scheme = 1;
129 |         } else if (path.starts_with("titan://")) {
130 |           request_scheme = 2;
131 |         } else {
132 |           request_scheme = 0;
133 |         }
134 | 
135 |         if (request_scheme != 0) {
136 |           bool request_valid = true;
137 | 
138 |           // Remove "\r\n" if Gemini
139 |           if (request_scheme == 1) {
140 |             if (path.size() < 2) {
141 |               std::cout << "received malformed gemini request\n";
142 | 
143 |               request_valid = false;
144 |             } else {
145 |               path.resize(path.size() - 2);
146 |             }
147 |           }
148 | 
149 |           if (request_valid) {
150 |             if (request_scheme == 1) {
151 |               constexpr std::size_t GEMINI_PROTOCOL_LENGTH = 9;
152 | 
153 |               path.erase(0, GEMINI_PROTOCOL_LENGTH); // Remove "gemini://"
154 |             } else {
155 |               constexpr std::size_t TITAN_PROTOCOL_LENGTH = 8;
156 | 
157 |               path.erase(0, TITAN_PROTOCOL_LENGTH); // Remove "titan://"
158 |             }
159 | 
160 |             // Try to remove the host, if you cannot; it must be a trailing
161 |             // slash-less hostname, so we will respond with the index.
162 |             const std::size_t found_first = path.find_first_of('/');
163 | 
164 |             if (found_first != std::string::npos) {
165 |               path = path.substr(found_first,
166 |                                  path.size() - 1); // Remove host
167 |             } else {
168 |               path = "/index.gmi";
169 |             }
170 | 
171 |             if (request_scheme == 1) {
172 |               // Remove junk, if any
173 |               index_of_junk = path.find_first_of('\n');
174 | 
175 |               if (index_of_junk != std::string::npos) {
176 |                 path.erase(path.find_first_of('\n') - 1, path.size() - 1);
177 |               }
178 |             }
179 | 
180 |             // Gemini
181 |             if (request_scheme == 1) {
182 |               maple::gemini::handle_client(gemini_files, path, response);
183 |             } else { // Titan
184 |               if (!titan) {
185 |                 response
186 |                     << "20 text/gemini\r\nThe server (Maple) does not have "
187 |                        "Titan support enabled!";
188 |               } else {
189 |                 maple::titan::handle_client(response, path, titan_token,
190 |                                             titan_max_size);
191 |               }
192 |             }
193 | 
194 |             const std::string response_string = response.str();
195 |             const int bytes_written =
196 |                 SSL_write(ssl, response_string.c_str(),
197 |                           static_cast<int>(response_string.size()));
198 | 
199 |             if (bytes_written <= 0) {
200 |               ERR_print_errors_fp(stderr);
201 |             }
202 |           }
203 |         } else {
204 |           std::cout << "received a request with an unsupported url scheme\n";
205 |         }
206 |       } else {
207 |         ERR_print_errors_fp(stderr);
208 |       }
209 |     }
210 | 
211 |     SSL_shutdown(ssl);
212 |     SSL_free(ssl);
213 |     close(client);
214 |   }
215 | }
216 | 
217 | namespace maple {
218 | auto prepare_exit_with(const char *message, bool ssl) -> int {
219 |   perror(message);
220 | 
221 |   if (ssl) {
222 |     ERR_print_errors_fp(stderr);
223 |   }
224 | 
225 |   return EXIT_FAILURE;
226 | }
227 | 
228 | auto setup_environment(bool &titan, std::string &titan_token,
229 |                        std::size_t &titan_max_size) -> int {
230 |   char *titan_environment = std::getenv("TITAN");
231 | 
232 |   if (titan_environment == nullptr) {
233 |     titan = false;
234 |   } else {
235 |     std::string valid_titan_environment(titan_environment);
236 | 
237 |     std::transform(
238 |         valid_titan_environment.begin(), valid_titan_environment.end(),
239 |         valid_titan_environment.begin(),
240 |         [](unsigned char character) -> int { return std::tolower(character); });
241 | 
242 |     if (valid_titan_environment == "true" || valid_titan_environment == "1") {
243 |       char *unvalidated_titan_token = std::getenv("TITAN_TOKEN");
244 |       char *unvalidated_titan_max_size = std::getenv("TITAN_MAX_SIZE");
245 | 
246 |       if (unvalidated_titan_token == nullptr) {
247 |         titan_token = "";
248 |       } else {
249 |         titan_token = std::string(unvalidated_titan_token);
250 |       }
251 | 
252 |       if (unvalidated_titan_max_size == nullptr) {
253 |         constexpr std::size_t TITAN_MAX_SIZE = 1024;
254 | 
255 |         titan_max_size = TITAN_MAX_SIZE;
256 | 
257 |         std::cout << "no TITAN_MAX_SIZE set, defaulting to 1024\n";
258 |       } else {
259 |         try {
260 |           titan_max_size =
261 |               static_cast<std::size_t>(std::stoi(unvalidated_titan_max_size));
262 |         } catch (...) {
263 |           return maple::prepare_exit_with(
264 |               "TITAN_MAX_SIZE could not be interpreted as an integer", false);
265 |         }
266 |       }
267 | 
268 |       titan = true;
269 |     }
270 |   }
271 | 
272 |   return 0;
273 | }
274 | 
275 | auto setup_ssl() -> int {
276 |   sockaddr_in socket_address{};
277 | 
278 |   // Setup OpenSSL
279 |   SSL_library_init();
280 |   SSL_load_error_strings();
281 | 
282 |   maple::ssl_context = SSL_CTX_new(TLS_server_method());
283 | 
284 |   if (maple::ssl_context == nullptr) {
285 |     return maple::prepare_exit_with("unable to create ssl context", true);
286 |   }
287 | 
288 |   if (SSL_CTX_use_certificate_file(maple::ssl_context, ".maple/public.pem",
289 |                                    SSL_FILETYPE_PEM) <= 0) {
290 |     return maple::prepare_exit_with("unable to use certificate file", true);
291 |   }
292 | 
293 |   if (SSL_CTX_use_PrivateKey_file(maple::ssl_context, ".maple/private.pem",
294 |                                   SSL_FILETYPE_PEM) <= 0) {
295 |     return maple::prepare_exit_with("unable to use private key file", true);
296 |   }
297 | 
298 |   constexpr std::size_t GEMINI_PORT = 1965;
299 | 
300 |   socket_address.sin_family = AF_INET;
301 |   socket_address.sin_port = htons(GEMINI_PORT);
302 |   socket_address.sin_addr.s_addr = htonl(INADDR_ANY);
303 | 
304 |   maple::maple_socket = socket(AF_INET, SOCK_STREAM, 0);
305 | 
306 |   if (maple::maple_socket < 0) {
307 |     return maple::prepare_exit_with("unable to create socket", false);
308 |   }
309 | 
310 |   // Reuse address. Allows the use of the address instantly after a SIGINT
311 |   // without having to wait for the socket to die.
312 |   int reuse_addr = 1;
313 | 
314 |   if (setsockopt(maple::maple_socket, SOL_SOCKET, SO_REUSEADDR, &reuse_addr,
315 |                  sizeof(int)) < 0) {
316 |     return maple::prepare_exit_with("unable to set socket options (SO_LINGER)",
317 |                                     false);
318 |   }
319 | 
320 |   if (bind(maple::maple_socket, reinterpret_cast<sockaddr *>(&socket_address),
321 |            sizeof(socket_address)) < 0) {
322 |     return maple::prepare_exit_with("unable to bind", false);
323 |   }
324 | 
325 |   if (listen(maple::maple_socket, 1) < 0) {
326 |     return maple::prepare_exit_with("unable to listen", false);
327 |   }
328 | 
329 |   return 0;
330 | }
331 | } // namespace maple
332 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
  1 |                     GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
  3 | 
  4 |  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
  5 |  Everyone is permitted to copy and distribute verbatim copies
  6 |  of this license document, but changing it is not allowed.
  7 | 
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 11 | software and other kinds of works.
 12 | 
 13 |   The licenses for most software and other practical works are designed
 14 | to take away your freedom to share and change the works.  By contrast,
 15 | the GNU General Public License is intended to guarantee your freedom to
 16 | share and change all versions of a program--to make sure it remains free
 17 | software for all its users.  We, the Free Software Foundation, use the
 18 | GNU General Public License for most of our software; it applies also to
 19 | any other work released this way by its authors.  You can apply it to
 20 | your programs, too.
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 23 | price.  Our General Public Licenses are designed to make sure that you
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177 | makes it unnecessary.
178 | 
179 |   3. Protecting Users' Legal Rights From Anti-Circumvention Law.
180 | 
181 |   No covered work shall be deemed part of an effective technological
182 | measure under any applicable law fulfilling obligations under article
183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or
184 | similar laws prohibiting or restricting circumvention of such
185 | measures.
186 | 
187 |   When you convey a covered work, you waive any legal power to forbid
188 | circumvention of technological measures to the extent such circumvention
189 | is effected by exercising rights under this License with respect to
190 | the covered work, and you disclaim any intention to limit operation or
191 | modification of the work as a means of enforcing, against the work's
192 | users, your or third parties' legal rights to forbid circumvention of
193 | technological measures.
194 | 
195 |   4. Conveying Verbatim Copies.
196 | 
197 |   You may convey verbatim copies of the Program's source code as you
198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 | 
205 |   You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 | 
208 |   5. Conveying Modified Source Versions.
209 | 
210 |   You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 | 
214 |     a) The work must carry prominent notices stating that you modified
215 |     it, and giving a relevant date.
216 | 
217 |     b) The work must carry prominent notices stating that it is
218 |     released under this License and any conditions added under section
219 |     7.  This requirement modifies the requirement in section 4 to
220 |     "keep intact all notices".
221 | 
222 |     c) You must license the entire work, as a whole, under this
223 |     License to anyone who comes into possession of a copy.  This
224 |     License will therefore apply, along with any applicable section 7
225 |     additional terms, to the whole of the work, and all its parts,
226 |     regardless of how they are packaged.  This License gives no
227 |     permission to license the work in any other way, but it does not
228 |     invalidate such permission if you have separately received it.
229 | 
230 |     d) If the work has interactive user interfaces, each must display
231 |     Appropriate Legal Notices; however, if the Program has interactive
232 |     interfaces that do not display Appropriate Legal Notices, your
233 |     work need not make them do so.
234 | 
235 |   A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit.  Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 | 
245 |   6. Conveying Non-Source Forms.
246 | 
247 |   You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 | 
252 |     a) Convey the object code in, or embodied in, a physical product
253 |     (including a physical distribution medium), accompanied by the
254 |     Corresponding Source fixed on a durable physical medium
255 |     customarily used for software interchange.
256 | 
257 |     b) Convey the object code in, or embodied in, a physical product
258 |     (including a physical distribution medium), accompanied by a
259 |     written offer, valid for at least three years and valid for as
260 |     long as you offer spare parts or customer support for that product
261 |     model, to give anyone who possesses the object code either (1) a
262 |     copy of the Corresponding Source for all the software in the
263 |     product that is covered by this License, on a durable physical
264 |     medium customarily used for software interchange, for a price no
265 |     more than your reasonable cost of physically performing this
266 |     conveying of source, or (2) access to copy the
267 |     Corresponding Source from a network server at no charge.
268 | 
269 |     c) Convey individual copies of the object code with a copy of the
270 |     written offer to provide the Corresponding Source.  This
271 |     alternative is allowed only occasionally and noncommercially, and
272 |     only if you received the object code with such an offer, in accord
273 |     with subsection 6b.
274 | 
275 |     d) Convey the object code by offering access from a designated
276 |     place (gratis or for a charge), and offer equivalent access to the
277 |     Corresponding Source in the same way through the same place at no
278 |     further charge.  You need not require recipients to copy the
279 |     Corresponding Source along with the object code.  If the place to
280 |     copy the object code is a network server, the Corresponding Source
281 |     may be on a different server (operated by you or a third party)
282 |     that supports equivalent copying facilities, provided you maintain
283 |     clear directions next to the object code saying where to find the
284 |     Corresponding Source.  Regardless of what server hosts the
285 |     Corresponding Source, you remain obligated to ensure that it is
286 |     available for as long as needed to satisfy these requirements.
287 | 
288 |     e) Convey the object code using peer-to-peer transmission, provided
289 |     you inform other peers where the object code and Corresponding
290 |     Source of the work are being offered to the general public at no
291 |     charge under subsection 6d.
292 | 
293 |   A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 | 
297 |   A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
299 | or household purposes, or (2) anything designed or sold for incorporation
300 | into a dwelling.  In determining whether a product is a consumer product,
301 | doubtful cases shall be resolved in favor of coverage.  For a particular
302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product.  A product
306 | is a consumer product regardless of whether the product has substantial
307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 | 
310 |   "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source.  The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 | 
318 |   If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information.  But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 | 
329 |   The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed.  Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 | 
337 |   Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 | 
343 |   7. Additional Terms.
344 | 
345 |   "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law.  If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 | 
354 |   When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it.  (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.)  You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 | 
361 |   Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 | 
365 |     a) Disclaiming warranty or limiting liability differently from the
366 |     terms of sections 15 and 16 of this License; or
367 | 
368 |     b) Requiring preservation of specified reasonable legal notices or
369 |     author attributions in that material or in the Appropriate Legal
370 |     Notices displayed by works containing it; or
371 | 
372 |     c) Prohibiting misrepresentation of the origin of that material, or
373 |     requiring that modified versions of such material be marked in
374 |     reasonable ways as different from the original version; or
375 | 
376 |     d) Limiting the use for publicity purposes of names of licensors or
377 |     authors of the material; or
378 | 
379 |     e) Declining to grant rights under trademark law for use of some
380 |     trade names, trademarks, or service marks; or
381 | 
382 |     f) Requiring indemnification of licensors and authors of that
383 |     material by anyone who conveys the material (or modified versions of
384 |     it) with contractual assumptions of liability to the recipient, for
385 |     any liability that these contractual assumptions directly impose on
386 |     those licensors and authors.
387 | 
388 |   All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10.  If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term.  If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 | 
398 |   If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 | 
403 |   Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 | 
407 |   8. Termination.
408 | 
409 |   You may not propagate or modify a covered work except as expressly
410 | provided under this License.  Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 | 
415 |   However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 | 
422 |   Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 | 
429 |   Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License.  If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 | 
435 |   9. Acceptance Not Required for Having Copies.
436 | 
437 |   You are not required to accept this License in order to receive or
438 | run a copy of the Program.  Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance.  However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work.  These actions infringe copyright if you do
443 | not accept this License.  Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 | 
446 |   10. Automatic Licensing of Downstream Recipients.
447 | 
448 |   Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License.  You are not responsible
451 | for enforcing compliance by third parties with this License.
452 | 
453 |   An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations.  If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 | 
463 |   You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License.  For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 | 
471 |   11. Patents.
472 | 
473 |   A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based.  The
475 | work thus licensed is called the contributor's "contributor version".
476 | 
477 |   A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version.  For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 | 
487 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 | 
492 |   In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement).  To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 | 
499 |   If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients.  "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 | 
513 |   If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 | 
521 |   A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     <one line to give the program's name and a brief idea of what it does.>
635 |     Copyright (C) <year>  <name of author>
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <https://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     <program>  Copyright (C) <year>  <name of author>
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <https://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


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