5e70acb9a6c8bd60be59854598bb9f1fb60fb643
1#include "cache.h"
2#include "quote.h"
3#include "exec_cmd.h"
4#include "strbuf.h"
5#include "run-command.h"
6
7#define COMMAND_DIR "git-shell-commands"
8#define HELP_COMMAND COMMAND_DIR "/help"
9#define NOLOGIN_COMMAND COMMAND_DIR "/no-interactive-login"
10
11static int do_generic_cmd(const char *me, char *arg)
12{
13 const char *my_argv[4];
14
15 setup_path();
16 if (!arg || !(arg = sq_dequote(arg)))
17 die("bad argument");
18 if (!starts_with(me, "git-"))
19 die("bad command");
20
21 my_argv[0] = me + 4;
22 my_argv[1] = arg;
23 my_argv[2] = NULL;
24
25 return execv_git_cmd(my_argv);
26}
27
28static int do_cvs_cmd(const char *me, char *arg)
29{
30 const char *cvsserver_argv[3] = {
31 "cvsserver", "server", NULL
32 };
33
34 if (!arg || strcmp(arg, "server"))
35 die("git-cvsserver only handles server: %s", arg);
36
37 setup_path();
38 return execv_git_cmd(cvsserver_argv);
39}
40
41static int is_valid_cmd_name(const char *cmd)
42{
43 /* Test command contains no . or / characters */
44 return cmd[strcspn(cmd, "./")] == '\0';
45}
46
47static char *make_cmd(const char *prog)
48{
49 return xstrfmt("%s/%s", COMMAND_DIR, prog);
50}
51
52static void cd_to_homedir(void)
53{
54 const char *home = getenv("HOME");
55 if (!home)
56 die("could not determine user's home directory; HOME is unset");
57 if (chdir(home) == -1)
58 die("could not chdir to user's home directory");
59}
60
61static void run_shell(void)
62{
63 int done = 0;
64 static const char *help_argv[] = { HELP_COMMAND, NULL };
65
66 if (!access(NOLOGIN_COMMAND, F_OK)) {
67 /* Interactive login disabled. */
68 const char *argv[] = { NOLOGIN_COMMAND, NULL };
69 int status;
70
71 status = run_command_v_opt(argv, 0);
72 if (status < 0)
73 exit(127);
74 exit(status);
75 }
76
77 /* Print help if enabled */
78 run_command_v_opt(help_argv, RUN_SILENT_EXEC_FAILURE);
79
80 do {
81 struct strbuf line = STRBUF_INIT;
82 const char *prog;
83 char *full_cmd;
84 char *rawargs;
85 char *split_args;
86 const char **argv;
87 int code;
88 int count;
89
90 fprintf(stderr, "git> ");
91 if (strbuf_getline_lf(&line, stdin) == EOF) {
92 fprintf(stderr, "\n");
93 strbuf_release(&line);
94 break;
95 }
96 strbuf_trim(&line);
97 rawargs = strbuf_detach(&line, NULL);
98 split_args = xstrdup(rawargs);
99 count = split_cmdline(split_args, &argv);
100 if (count < 0) {
101 fprintf(stderr, "invalid command format '%s': %s\n", rawargs,
102 split_cmdline_strerror(count));
103 free(split_args);
104 free(rawargs);
105 continue;
106 }
107
108 prog = argv[0];
109 if (!strcmp(prog, "")) {
110 } else if (!strcmp(prog, "quit") || !strcmp(prog, "logout") ||
111 !strcmp(prog, "exit") || !strcmp(prog, "bye")) {
112 done = 1;
113 } else if (is_valid_cmd_name(prog)) {
114 full_cmd = make_cmd(prog);
115 argv[0] = full_cmd;
116 code = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE);
117 if (code == -1 && errno == ENOENT) {
118 fprintf(stderr, "unrecognized command '%s'\n", prog);
119 }
120 free(full_cmd);
121 } else {
122 fprintf(stderr, "invalid command format '%s'\n", prog);
123 }
124
125 free(argv);
126 free(rawargs);
127 } while (!done);
128}
129
130static struct commands {
131 const char *name;
132 int (*exec)(const char *me, char *arg);
133} cmd_list[] = {
134 { "git-receive-pack", do_generic_cmd },
135 { "git-upload-pack", do_generic_cmd },
136 { "git-upload-archive", do_generic_cmd },
137 { "cvs", do_cvs_cmd },
138 { NULL },
139};
140
141int cmd_main(int argc, const char **argv)
142{
143 char *prog;
144 const char **user_argv;
145 struct commands *cmd;
146 int count;
147
148 git_setup_gettext();
149
150 /*
151 * Special hack to pretend to be a CVS server
152 */
153 if (argc == 2 && !strcmp(argv[1], "cvs server")) {
154 argv--;
155 } else if (argc == 1) {
156 /* Allow the user to run an interactive shell */
157 cd_to_homedir();
158 if (access(COMMAND_DIR, R_OK | X_OK) == -1) {
159 die("Interactive git shell is not enabled.\n"
160 "hint: ~/" COMMAND_DIR " should exist "
161 "and have read and execute access.");
162 }
163 run_shell();
164 exit(0);
165 } else if (argc != 3 || strcmp(argv[1], "-c")) {
166 /*
167 * We do not accept any other modes except "-c" followed by
168 * "cmd arg", where "cmd" is a very limited subset of git
169 * commands or a command in the COMMAND_DIR
170 */
171 die("Run with no arguments or with -c cmd");
172 }
173
174 prog = xstrdup(argv[2]);
175 if (!strncmp(prog, "git", 3) && isspace(prog[3]))
176 /* Accept "git foo" as if the caller said "git-foo". */
177 prog[3] = '-';
178
179 for (cmd = cmd_list ; cmd->name ; cmd++) {
180 int len = strlen(cmd->name);
181 char *arg;
182 if (strncmp(cmd->name, prog, len))
183 continue;
184 arg = NULL;
185 switch (prog[len]) {
186 case '\0':
187 arg = NULL;
188 break;
189 case ' ':
190 arg = prog + len + 1;
191 break;
192 default:
193 continue;
194 }
195 exit(cmd->exec(cmd->name, arg));
196 }
197
198 cd_to_homedir();
199 count = split_cmdline(prog, &user_argv);
200 if (count >= 0) {
201 if (is_valid_cmd_name(user_argv[0])) {
202 prog = make_cmd(user_argv[0]);
203 user_argv[0] = prog;
204 execv(user_argv[0], (char *const *) user_argv);
205 }
206 free(prog);
207 free(user_argv);
208 die("unrecognized command '%s'", argv[2]);
209 } else {
210 free(prog);
211 die("invalid command format '%s': %s", argv[2],
212 split_cmdline_strerror(count));
213 }
214}