2 d65a88a2 2021-09-05 stsp * Copyright (c) 2018, 2019 Ori Bernstein <ori@openbsd.org>
3 d65a88a2 2021-09-05 stsp * Copyright (c) 2021 Stefan Sperling <stsp@openbsd.org>
5 d65a88a2 2021-09-05 stsp * Permission to use, copy, modify, and distribute this software for any
6 d65a88a2 2021-09-05 stsp * purpose with or without fee is hereby granted, provided that the above
7 d65a88a2 2021-09-05 stsp * copyright notice and this permission notice appear in all copies.
9 d65a88a2 2021-09-05 stsp * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 d65a88a2 2021-09-05 stsp * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 d65a88a2 2021-09-05 stsp * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 d65a88a2 2021-09-05 stsp * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 d65a88a2 2021-09-05 stsp * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 d65a88a2 2021-09-05 stsp * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 d65a88a2 2021-09-05 stsp * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 5e5da8c4 2021-09-05 stsp #include <sys/queue.h>
19 d65a88a2 2021-09-05 stsp #include <sys/types.h>
20 d65a88a2 2021-09-05 stsp #include <sys/socket.h>
21 d65a88a2 2021-09-05 stsp #include <netdb.h>
23 c10270f6 2021-09-06 naddy #include <assert.h>
24 d65a88a2 2021-09-05 stsp #include <err.h>
25 6cc8a118 2023-03-10 op #include <limits.h>
26 d65a88a2 2021-09-05 stsp #include <stdio.h>
27 d65a88a2 2021-09-05 stsp #include <stdlib.h>
28 d65a88a2 2021-09-05 stsp #include <string.h>
29 d65a88a2 2021-09-05 stsp #include <unistd.h>
31 d65a88a2 2021-09-05 stsp #include "got_error.h"
32 5e5da8c4 2021-09-05 stsp #include "got_path.h"
34 d65a88a2 2021-09-05 stsp #include "got_lib_dial.h"
35 336075a4 2022-06-25 op #include "got_dial.h"
37 c10270f6 2021-09-06 naddy #ifndef nitems
38 c10270f6 2021-09-06 naddy #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
41 d65a88a2 2021-09-05 stsp #ifndef ssizeof
42 d65a88a2 2021-09-05 stsp #define ssizeof(_x) ((ssize_t)(sizeof(_x)))
46 d65a88a2 2021-09-05 stsp #define MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
49 d65a88a2 2021-09-05 stsp #ifndef GOT_DIAL_PATH_SSH
50 d65a88a2 2021-09-05 stsp #define GOT_DIAL_PATH_SSH "/usr/bin/ssh"
53 d65a88a2 2021-09-05 stsp /* IANA assigned */
54 d65a88a2 2021-09-05 stsp #define GOT_DEFAULT_GIT_PORT 9418
55 d65a88a2 2021-09-05 stsp #define GOT_DEFAULT_GIT_PORT_STR "9418"
57 d65a88a2 2021-09-05 stsp const struct got_error *
58 d65a88a2 2021-09-05 stsp got_dial_apply_unveil(const char *proto)
60 d65a88a2 2021-09-05 stsp if (strcmp(proto, "git+ssh") == 0 || strcmp(proto, "ssh") == 0) {
61 d65a88a2 2021-09-05 stsp if (unveil(GOT_DIAL_PATH_SSH, "x") != 0) {
62 d65a88a2 2021-09-05 stsp return got_error_from_errno2("unveil",
63 d65a88a2 2021-09-05 stsp GOT_DIAL_PATH_SSH);
67 d65a88a2 2021-09-05 stsp return NULL;
71 58e31a80 2022-06-27 op hassuffix(const char *base, const char *suf)
75 5e5da8c4 2021-09-05 stsp nb = strlen(base);
76 5e5da8c4 2021-09-05 stsp ns = strlen(suf);
77 5e5da8c4 2021-09-05 stsp if (ns <= nb && strcmp(base + (nb - ns), suf) == 0)
82 d65a88a2 2021-09-05 stsp const struct got_error *
83 5e5da8c4 2021-09-05 stsp got_dial_parse_uri(char **proto, char **host, char **port,
84 5e5da8c4 2021-09-05 stsp char **server_path, char **repo_name, const char *uri)
86 5e5da8c4 2021-09-05 stsp const struct got_error *err = NULL;
87 5e5da8c4 2021-09-05 stsp char *s, *p, *q;
89 5e5da8c4 2021-09-05 stsp *proto = *host = *port = *server_path = *repo_name = NULL;
91 5e5da8c4 2021-09-05 stsp p = strstr(uri, "://");
93 5e5da8c4 2021-09-05 stsp /* Try parsing Git's "scp" style URL syntax. */
94 5e5da8c4 2021-09-05 stsp *proto = strdup("ssh");
95 805253d5 2022-03-07 naddy if (*proto == NULL) {
96 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strdup");
99 5e5da8c4 2021-09-05 stsp s = (char *)uri;
100 5e5da8c4 2021-09-05 stsp q = strchr(s, ':');
101 5e5da8c4 2021-09-05 stsp if (q == NULL) {
102 5e5da8c4 2021-09-05 stsp err = got_error(GOT_ERR_PARSE_URI);
105 5e5da8c4 2021-09-05 stsp /* No slashes allowed before first colon. */
106 5e5da8c4 2021-09-05 stsp p = strchr(s, '/');
107 5e5da8c4 2021-09-05 stsp if (p && q > p) {
108 5e5da8c4 2021-09-05 stsp err = got_error(GOT_ERR_PARSE_URI);
111 5e5da8c4 2021-09-05 stsp *host = strndup(s, q - s);
112 5e5da8c4 2021-09-05 stsp if (*host == NULL) {
113 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strndup");
116 3a12860c 2022-03-07 stsp if ((*host)[0] == '\0') {
117 3a12860c 2022-03-07 stsp err = got_error(GOT_ERR_PARSE_URI);
122 5e5da8c4 2021-09-05 stsp *proto = strndup(uri, p - uri);
123 805253d5 2022-03-07 naddy if (*proto == NULL) {
124 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strndup");
129 5e5da8c4 2021-09-05 stsp p = strstr(s, "/");
130 5e5da8c4 2021-09-05 stsp if (p == NULL || strlen(p) == 1) {
131 5e5da8c4 2021-09-05 stsp err = got_error(GOT_ERR_PARSE_URI);
135 5e5da8c4 2021-09-05 stsp q = memchr(s, ':', p - s);
137 5e5da8c4 2021-09-05 stsp *host = strndup(s, q - s);
138 5e5da8c4 2021-09-05 stsp if (*host == NULL) {
139 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strndup");
142 3a12860c 2022-03-07 stsp if ((*host)[0] == '\0') {
143 3a12860c 2022-03-07 stsp err = got_error(GOT_ERR_PARSE_URI);
146 5e5da8c4 2021-09-05 stsp *port = strndup(q + 1, p - (q + 1));
147 5e5da8c4 2021-09-05 stsp if (*port == NULL) {
148 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strndup");
151 3a12860c 2022-03-07 stsp if ((*port)[0] == '\0') {
152 3a12860c 2022-03-07 stsp err = got_error(GOT_ERR_PARSE_URI);
156 5e5da8c4 2021-09-05 stsp *host = strndup(s, p - s);
157 5e5da8c4 2021-09-05 stsp if (*host == NULL) {
158 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strndup");
161 3a12860c 2022-03-07 stsp if ((*host)[0] == '\0') {
162 3a12860c 2022-03-07 stsp err = got_error(GOT_ERR_PARSE_URI);
168 5e5da8c4 2021-09-05 stsp while (p[0] == '/' && p[1] == '/')
170 5e5da8c4 2021-09-05 stsp *server_path = strdup(p);
171 5e5da8c4 2021-09-05 stsp if (*server_path == NULL) {
172 5e5da8c4 2021-09-05 stsp err = got_error_from_errno("strdup");
175 5e5da8c4 2021-09-05 stsp got_path_strip_trailing_slashes(*server_path);
176 3a12860c 2022-03-07 stsp if ((*server_path)[0] == '\0') {
177 5e5da8c4 2021-09-05 stsp err = got_error(GOT_ERR_PARSE_URI);
181 3a12860c 2022-03-07 stsp err = got_path_basename(repo_name, *server_path);
184 3a12860c 2022-03-07 stsp if (hassuffix(*repo_name, ".git"))
185 3a12860c 2022-03-07 stsp (*repo_name)[strlen(*repo_name) - 4] = '\0';
186 3a12860c 2022-03-07 stsp if ((*repo_name)[0] == '\0')
187 3a12860c 2022-03-07 stsp err = got_error(GOT_ERR_PARSE_URI);
190 5e5da8c4 2021-09-05 stsp free(*proto);
191 5e5da8c4 2021-09-05 stsp *proto = NULL;
192 5e5da8c4 2021-09-05 stsp free(*host);
193 5e5da8c4 2021-09-05 stsp *host = NULL;
194 5e5da8c4 2021-09-05 stsp free(*port);
195 5e5da8c4 2021-09-05 stsp *port = NULL;
196 5e5da8c4 2021-09-05 stsp free(*server_path);
197 5e5da8c4 2021-09-05 stsp *server_path = NULL;
198 5e5da8c4 2021-09-05 stsp free(*repo_name);
199 5e5da8c4 2021-09-05 stsp *repo_name = NULL;
201 5e5da8c4 2021-09-05 stsp return err;
205 6cc8a118 2023-03-10 op * Escape a given path for the shell which will be started by sshd.
206 6cc8a118 2023-03-10 op * In particular, git-shell is known to require single-quote characters
207 6cc8a118 2023-03-10 op * around its repository path argument and will refuse to run otherwise.
209 6cc8a118 2023-03-10 op static const struct got_error *
210 6cc8a118 2023-03-10 op escape_path(char *buf, size_t bufsize, const char *path)
212 6cc8a118 2023-03-10 op const char *p;
218 6cc8a118 2023-03-10 op if (bufsize > 1)
221 6cc8a118 2023-03-10 op while (*p != '\0' && (q - buf < bufsize)) {
222 6cc8a118 2023-03-10 op /* git escapes ! too */
223 6cc8a118 2023-03-10 op if (*p != '\'' && *p != '!') {
228 6cc8a118 2023-03-10 op if (q - buf + 4 >= bufsize)
236 6cc8a118 2023-03-10 op if (*p == '\0' && (q - buf + 1 < bufsize)) {
242 6cc8a118 2023-03-10 op return got_error_fmt(GOT_ERR_NO_SPACE, "overlong path: %s", path);
245 5e5da8c4 2021-09-05 stsp const struct got_error *
246 d65a88a2 2021-09-05 stsp got_dial_ssh(pid_t *newpid, int *newfd, const char *host,
247 d65a88a2 2021-09-05 stsp const char *port, const char *path, const char *direction, int verbosity)
249 d65a88a2 2021-09-05 stsp const struct got_error *error = NULL;
250 d65a88a2 2021-09-05 stsp int pid, pfd[2];
251 d65a88a2 2021-09-05 stsp char cmd[64];
252 6cc8a118 2023-03-10 op char escaped_path[PATH_MAX];
253 58e31a80 2022-06-27 op const char *argv[11];
254 d65a88a2 2021-09-05 stsp int i = 0, j;
256 d65a88a2 2021-09-05 stsp *newpid = -1;
257 d65a88a2 2021-09-05 stsp *newfd = -1;
259 6cc8a118 2023-03-10 op error = escape_path(escaped_path, sizeof(escaped_path), path);
261 6cc8a118 2023-03-10 op return error;
263 d65a88a2 2021-09-05 stsp argv[i++] = GOT_DIAL_PATH_SSH;
264 d65a88a2 2021-09-05 stsp if (port != NULL) {
265 d65a88a2 2021-09-05 stsp argv[i++] = "-p";
266 d65a88a2 2021-09-05 stsp argv[i++] = (char *)port;
268 d65a88a2 2021-09-05 stsp if (verbosity == -1) {
269 d65a88a2 2021-09-05 stsp argv[i++] = "-q";
271 d65a88a2 2021-09-05 stsp /* ssh(1) allows up to 3 "-v" options. */
272 d65a88a2 2021-09-05 stsp for (j = 0; j < MIN(3, verbosity); j++)
273 d65a88a2 2021-09-05 stsp argv[i++] = "-v";
275 d65a88a2 2021-09-05 stsp argv[i++] = "--";
276 d65a88a2 2021-09-05 stsp argv[i++] = (char *)host;
277 d65a88a2 2021-09-05 stsp argv[i++] = (char *)cmd;
278 6cc8a118 2023-03-10 op argv[i++] = (char *)escaped_path;
279 d65a88a2 2021-09-05 stsp argv[i++] = NULL;
280 c10270f6 2021-09-06 naddy assert(i <= nitems(argv));
282 d65a88a2 2021-09-05 stsp if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pfd) == -1)
283 d65a88a2 2021-09-05 stsp return got_error_from_errno("socketpair");
285 d65a88a2 2021-09-05 stsp pid = fork();
286 d65a88a2 2021-09-05 stsp if (pid == -1) {
287 d65a88a2 2021-09-05 stsp error = got_error_from_errno("fork");
288 d65a88a2 2021-09-05 stsp close(pfd[0]);
289 d65a88a2 2021-09-05 stsp close(pfd[1]);
290 d65a88a2 2021-09-05 stsp return error;
291 d65a88a2 2021-09-05 stsp } else if (pid == 0) {
293 d65a88a2 2021-09-05 stsp if (close(pfd[1]) == -1)
294 d65a88a2 2021-09-05 stsp err(1, "close");
295 d65a88a2 2021-09-05 stsp if (dup2(pfd[0], 0) == -1)
296 d65a88a2 2021-09-05 stsp err(1, "dup2");
297 d65a88a2 2021-09-05 stsp if (dup2(pfd[0], 1) == -1)
298 d65a88a2 2021-09-05 stsp err(1, "dup2");
299 d65a88a2 2021-09-05 stsp n = snprintf(cmd, sizeof(cmd), "git-%s-pack", direction);
300 d65a88a2 2021-09-05 stsp if (n < 0 || n >= ssizeof(cmd))
301 d65a88a2 2021-09-05 stsp err(1, "snprintf");
302 58e31a80 2022-06-27 op if (execv(GOT_DIAL_PATH_SSH, (char *const *)argv) == -1)
303 d65a88a2 2021-09-05 stsp err(1, "execv");
304 d65a88a2 2021-09-05 stsp abort(); /* not reached */
306 d65a88a2 2021-09-05 stsp if (close(pfd[0]) == -1)
307 d65a88a2 2021-09-05 stsp return got_error_from_errno("close");
308 d65a88a2 2021-09-05 stsp *newpid = pid;
309 d65a88a2 2021-09-05 stsp *newfd = pfd[1];
310 d65a88a2 2021-09-05 stsp return NULL;
314 d65a88a2 2021-09-05 stsp const struct got_error *
315 d65a88a2 2021-09-05 stsp got_dial_git(int *newfd, const char *host, const char *port,
316 d65a88a2 2021-09-05 stsp const char *path, const char *direction)
318 d65a88a2 2021-09-05 stsp const struct got_error *err = NULL;
319 d65a88a2 2021-09-05 stsp struct addrinfo hints, *servinfo, *p;
320 d65a88a2 2021-09-05 stsp char *cmd = NULL;
321 d65a88a2 2021-09-05 stsp int fd = -1, len, r, eaicode;
323 d65a88a2 2021-09-05 stsp *newfd = -1;
325 d65a88a2 2021-09-05 stsp if (port == NULL)
326 d65a88a2 2021-09-05 stsp port = GOT_DEFAULT_GIT_PORT_STR;
328 d65a88a2 2021-09-05 stsp memset(&hints, 0, sizeof hints);
329 d65a88a2 2021-09-05 stsp hints.ai_family = AF_UNSPEC;
330 d65a88a2 2021-09-05 stsp hints.ai_socktype = SOCK_STREAM;
331 d65a88a2 2021-09-05 stsp eaicode = getaddrinfo(host, port, &hints, &servinfo);
332 d65a88a2 2021-09-05 stsp if (eaicode) {
333 d65a88a2 2021-09-05 stsp char msg[512];
334 d65a88a2 2021-09-05 stsp snprintf(msg, sizeof(msg), "%s: %s", host,
335 d65a88a2 2021-09-05 stsp gai_strerror(eaicode));
336 d65a88a2 2021-09-05 stsp return got_error_msg(GOT_ERR_ADDRINFO, msg);
339 d65a88a2 2021-09-05 stsp for (p = servinfo; p != NULL; p = p->ai_next) {
340 d65a88a2 2021-09-05 stsp if ((fd = socket(p->ai_family, p->ai_socktype,
341 d65a88a2 2021-09-05 stsp p->ai_protocol)) == -1)
343 d65a88a2 2021-09-05 stsp if (connect(fd, p->ai_addr, p->ai_addrlen) == 0) {
344 d65a88a2 2021-09-05 stsp err = NULL;
347 d65a88a2 2021-09-05 stsp err = got_error_from_errno("connect");
350 9ea55f08 2022-09-05 op freeaddrinfo(servinfo);
351 d65a88a2 2021-09-05 stsp if (p == NULL)
354 d65a88a2 2021-09-05 stsp if (asprintf(&cmd, "git-%s-pack %s", direction, path) == -1) {
355 d65a88a2 2021-09-05 stsp err = got_error_from_errno("asprintf");
358 d65a88a2 2021-09-05 stsp len = 4 + strlen(cmd) + 1 + strlen("host=") + strlen(host) + 1;
359 d65a88a2 2021-09-05 stsp r = dprintf(fd, "%04x%s%chost=%s%c", len, cmd, '\0', host, '\0');
361 d65a88a2 2021-09-05 stsp err = got_error_from_errno("dprintf");
365 d65a88a2 2021-09-05 stsp if (fd != -1)
368 d65a88a2 2021-09-05 stsp *newfd = fd;
369 d65a88a2 2021-09-05 stsp return err;
