[thirdparty/git.git] / connect.c

#include "git-compat-util.h"
#include "cache.h"
#include "pkt-line.h"
#include "quote.h"
#include "refs.h"
#include "run-command.h"
#include "remote.h"

static char *server_capabilities;

static int check_ref(const char *name, int len, unsigned int flags)
{
	if (!flags)
		return 1;

	if (len < 5 || memcmp(name, "refs/", 5))
		return 0;

	/* Skip the "refs/" part */
	name += 5;
	len -= 5;

	/* REF_NORMAL means that we don't want the magic fake tag refs */
	if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
		return 0;

	/* REF_HEADS means that we want regular branch heads */
	if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
		return 1;

	/* REF_TAGS means that we want tags */
	if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
		return 1;

	/* All type bits clear means that we are ok with anything */
	return !(flags & ~REF_NORMAL);
}

/*
 * Read all the refs from the other end
 */
struct ref **get_remote_heads(int in, struct ref **list,
			      int nr_match, char **match,
			      unsigned int flags)
{
	*list = NULL;
	for (;;) {
		struct ref *ref;
		unsigned char old_sha1[20];
		static char buffer[1000];
		char *name;
		int len, name_len;

		len = packet_read_line(in, buffer, sizeof(buffer));
		if (!len)
			break;
		if (buffer[len-1] == '\n')
			buffer[--len] = 0;

		if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
			die("protocol error: expected sha/ref, got '%s'", buffer);
		name = buffer + 41;

		name_len = strlen(name);
		if (len != name_len + 41) {
			if (server_capabilities)
				free(server_capabilities);
			server_capabilities = xstrdup(name + name_len + 1);
		}

		if (!check_ref(name, name_len, flags))
			continue;
		if (nr_match && !path_match(name, nr_match, match))
			continue;
		ref = xcalloc(1, sizeof(*ref) + len - 40);
		hashcpy(ref->old_sha1, old_sha1);
		memcpy(ref->name, buffer + 41, len - 40);
		*list = ref;
		list = &ref->next;
	}
	return list;
}

int server_supports(const char *feature)
{
	return server_capabilities &&
		strstr(server_capabilities, feature) != NULL;
}

int get_ack(int fd, unsigned char *result_sha1)
{
	static char line[1000];
	int len = packet_read_line(fd, line, sizeof(line));

	if (!len)
		die("git-fetch-pack: expected ACK/NAK, got EOF");
	if (line[len-1] == '\n')
		line[--len] = 0;
	if (!strcmp(line, "NAK"))
		return 0;
	if (!prefixcmp(line, "ACK ")) {
		if (!get_sha1_hex(line+4, result_sha1)) {
			if (strstr(line+45, "continue"))
				return 2;
			return 1;
		}
	}
	die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
}

int path_match(const char *path, int nr, char **match)
{
	int i;
	int pathlen = strlen(path);

	for (i = 0; i < nr; i++) {
		char *s = match[i];
		int len = strlen(s);

		if (!len || len > pathlen)
			continue;
		if (memcmp(path + pathlen - len, s, len))
			continue;
		if (pathlen > len && path[pathlen - len - 1] != '/')
			continue;
		*s = 0;
		return (i + 1);
	}
	return 0;
}

enum protocol {
	PROTO_LOCAL = 1,
	PROTO_SSH,
	PROTO_GIT,
};

static enum protocol get_protocol(const char *name)
{
	if (!strcmp(name, "ssh"))
		return PROTO_SSH;
	if (!strcmp(name, "git"))
		return PROTO_GIT;
	if (!strcmp(name, "git+ssh"))
		return PROTO_SSH;
	if (!strcmp(name, "ssh+git"))
		return PROTO_SSH;
	die("I don't handle protocol '%s'", name);
}

#define STR_(s)	# s
#define STR(s)	STR_(s)

#ifndef NO_IPV6

/*
 * Returns a connected socket() fd, or else die()s.
 */
static int git_tcp_connect_sock(char *host, int flags)
{
	int sockfd = -1, saved_errno = 0;
	char *colon, *end;
	const char *port = STR(DEFAULT_GIT_PORT);
	struct addrinfo hints, *ai0, *ai;
	int gai;

	if (host[0] == '[') {
		end = strchr(host + 1, ']');
		if (end) {
			*end = 0;
			end++;
			host++;
		} else
			end = host;
	} else
		end = host;
	colon = strchr(end, ':');

	if (colon) {
		*colon = 0;
		port = colon + 1;
		if (!*port)
			port = "<none>";
	}

	memset(&hints, 0, sizeof(hints));
	hints.ai_socktype = SOCK_STREAM;
	hints.ai_protocol = IPPROTO_TCP;

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "Looking up %s ... ", host);

	gai = getaddrinfo(host, port, &hints, &ai);
	if (gai)
		die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);

	for (ai0 = ai; ai; ai = ai->ai_next) {
		sockfd = socket(ai->ai_family,
				ai->ai_socktype, ai->ai_protocol);
		if (sockfd < 0) {
			saved_errno = errno;
			continue;
		}
		if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
			saved_errno = errno;
			close(sockfd);
			sockfd = -1;
			continue;
		}
		break;
	}

	freeaddrinfo(ai0);

	if (sockfd < 0)
		die("unable to connect a socket (%s)", strerror(saved_errno));

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "done.\n");

	return sockfd;
}

#else /* NO_IPV6 */

/*
 * Returns a connected socket() fd, or else die()s.
 */
static int git_tcp_connect_sock(char *host, int flags)
{
	int sockfd = -1, saved_errno = 0;
	char *colon, *end;
	char *port = STR(DEFAULT_GIT_PORT), *ep;
	struct hostent *he;
	struct sockaddr_in sa;
	char **ap;
	unsigned int nport;

	if (host[0] == '[') {
		end = strchr(host + 1, ']');
		if (end) {
			*end = 0;
			end++;
			host++;
		} else
			end = host;
	} else
		end = host;
	colon = strchr(end, ':');

	if (colon) {
		*colon = 0;
		port = colon + 1;
	}

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "Looking up %s ... ", host);

	he = gethostbyname(host);
	if (!he)
		die("Unable to look up %s (%s)", host, hstrerror(h_errno));
	nport = strtoul(port, &ep, 10);
	if ( ep == port || *ep ) {
		/* Not numeric */
		struct servent *se = getservbyname(port,"tcp");
		if ( !se )
			die("Unknown port %s\n", port);
		nport = se->s_port;
	}

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);

	for (ap = he->h_addr_list; *ap; ap++) {
		sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
		if (sockfd < 0) {
			saved_errno = errno;
			continue;
		}

		memset(&sa, 0, sizeof sa);
		sa.sin_family = he->h_addrtype;
		sa.sin_port = htons(nport);
		memcpy(&sa.sin_addr, *ap, he->h_length);

		if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
			saved_errno = errno;
			close(sockfd);
			sockfd = -1;
			continue;
		}
		break;
	}

	if (sockfd < 0)
		die("unable to connect a socket (%s)", strerror(saved_errno));

	if (flags & CONNECT_VERBOSE)
		fprintf(stderr, "done.\n");

	return sockfd;
}

#endif /* NO_IPV6 */


static void git_tcp_connect(int fd[2], char *host, int flags)
{
	int sockfd = git_tcp_connect_sock(host, flags);

	fd[0] = sockfd;
	fd[1] = dup(sockfd);
}


static char *git_proxy_command;
static const char *rhost_name;
static int rhost_len;

static int git_proxy_command_options(const char *var, const char *value)
{
	if (!strcmp(var, "core.gitproxy")) {
		const char *for_pos;
		int matchlen = -1;
		int hostlen;

		if (git_proxy_command)
			return 0;
		/* [core]
		 * ;# matches www.kernel.org as well
		 * gitproxy = netcatter-1 for kernel.org
		 * gitproxy = netcatter-2 for sample.xz
		 * gitproxy = netcatter-default
		 */
		for_pos = strstr(value, " for ");
		if (!for_pos)
			/* matches everybody */
			matchlen = strlen(value);
		else {
			hostlen = strlen(for_pos + 5);
			if (rhost_len < hostlen)
				matchlen = -1;
			else if (!strncmp(for_pos + 5,
					  rhost_name + rhost_len - hostlen,
					  hostlen) &&
				 ((rhost_len == hostlen) ||
				  rhost_name[rhost_len - hostlen -1] == '.'))
				matchlen = for_pos - value;
			else
				matchlen = -1;
		}
		if (0 <= matchlen) {
			/* core.gitproxy = none for kernel.org */
			if (matchlen == 4 && 
			    !memcmp(value, "none", 4))
				matchlen = 0;
			git_proxy_command = xmalloc(matchlen + 1);
			memcpy(git_proxy_command, value, matchlen);
			git_proxy_command[matchlen] = 0;
		}
		return 0;
	}

	return git_default_config(var, value);
}

static int git_use_proxy(const char *host)
{
	rhost_name = host;
	rhost_len = strlen(host);
	git_proxy_command = getenv("GIT_PROXY_COMMAND");
	git_config(git_proxy_command_options);
	rhost_name = NULL;
	return (git_proxy_command && *git_proxy_command);
}

static void git_proxy_connect(int fd[2], char *host)
{
	const char *port = STR(DEFAULT_GIT_PORT);
	char *colon, *end;
	const char *argv[4];
	struct child_process proxy;

	if (host[0] == '[') {
		end = strchr(host + 1, ']');
		if (end) {
			*end = 0;
			end++;
			host++;
		} else
			end = host;
	} else
		end = host;
	colon = strchr(end, ':');

	if (colon) {
		*colon = 0;
		port = colon + 1;
	}

	argv[0] = git_proxy_command;
	argv[1] = host;
	argv[2] = port;
	argv[3] = NULL;
	memset(&proxy, 0, sizeof(proxy));
	proxy.argv = argv;
	proxy.in = -1;
	proxy.out = -1;
	if (start_command(&proxy))
		die("cannot start proxy %s", argv[0]);
	fd[0] = proxy.out; /* read from proxy stdout */
	fd[1] = proxy.in;  /* write to proxy stdin */
}

#define MAX_CMD_LEN 1024

/*
 * This returns 0 if the transport protocol does not need fork(2),
 * or a process id if it does.  Once done, finish the connection
 * with finish_connect() with the value returned from this function
 * (it is safe to call finish_connect() with 0 to support the former
 * case).
 *
 * Does not return a negative value on error; it just dies.
 */
pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
{
	char *host, *path = url;
	char *end;
	int c;
	int pipefd[2][2];
	pid_t pid;
	enum protocol protocol = PROTO_LOCAL;
	int free_path = 0;

	/* Without this we cannot rely on waitpid() to tell
	 * what happened to our children.
	 */
	signal(SIGCHLD, SIG_DFL);

	host = strstr(url, "://");
	if(host) {
		*host = '\0';
		protocol = get_protocol(url);
		host += 3;
		c = '/';
	} else {
		host = url;
		c = ':';
	}

	if (host[0] == '[') {
		end = strchr(host + 1, ']');
		if (end) {
			*end = 0;
			end++;
			host++;
		} else
			end = host;
	} else
		end = host;

	path = strchr(end, c);
	if (c == ':') {
		if (path) {
			protocol = PROTO_SSH;
			*path++ = '\0';
		} else
			path = host;
	}

	if (!path || !*path)
		die("No path specified. See 'man git-pull' for valid url syntax");

	/*
	 * null-terminate hostname and point path to ~ for URL's like this:
	 *    ssh://host.xz/~user/repo
	 */
	if (protocol != PROTO_LOCAL && host != url) {
		char *ptr = path;
		if (path[1] == '~')
			path++;
		else {
			path = xstrdup(ptr);
			free_path = 1;
		}

		*ptr = '\0';
	}

	if (protocol == PROTO_GIT) {
		/* These underlying connection commands die() if they
		 * cannot connect.
		 */
		char *target_host = xstrdup(host);
		if (git_use_proxy(host))
			git_proxy_connect(fd, host);
		else
			git_tcp_connect(fd, host, flags);
		/*
		 * Separate original protocol components prog and path
		 * from extended components with a NUL byte.
		 */
		packet_write(fd[1],
			     "%s %s%chost=%s%c",
			     prog, path, 0,
			     target_host, 0);
		free(target_host);
		if (free_path)
			free(path);
		return 0;
	}

	if (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
		die("unable to create pipe pair for communication");
	pid = fork();
	if (pid < 0)
		die("unable to fork");
	if (!pid) {
		char command[MAX_CMD_LEN];
		char *posn = command;
		int size = MAX_CMD_LEN;
		int of = 0;

		of |= add_to_string(&posn, &size, prog, 0);
		of |= add_to_string(&posn, &size, " ", 0);
		of |= add_to_string(&posn, &size, path, 1);

		if (of)
			die("command line too long");

		dup2(pipefd[1][0], 0);
		dup2(pipefd[0][1], 1);
		close(pipefd[0][0]);
		close(pipefd[0][1]);
		close(pipefd[1][0]);
		close(pipefd[1][1]);
		if (protocol == PROTO_SSH) {
			const char *ssh, *ssh_basename;
			ssh = getenv("GIT_SSH");
			if (!ssh) ssh = "ssh";
			ssh_basename = strrchr(ssh, '/');
			if (!ssh_basename)
				ssh_basename = ssh;
			else
				ssh_basename++;
			execlp(ssh, ssh_basename, host, command, NULL);
		}
		else {
			unsetenv(ALTERNATE_DB_ENVIRONMENT);
			unsetenv(DB_ENVIRONMENT);
			unsetenv(GIT_DIR_ENVIRONMENT);
			unsetenv(GRAFT_ENVIRONMENT);
			unsetenv(INDEX_ENVIRONMENT);
			execlp("sh", "sh", "-c", command, NULL);
		}
		die("exec failed");
	}
	fd[0] = pipefd[0][0];
	fd[1] = pipefd[1][1];
	close(pipefd[0][1]);
	close(pipefd[1][0]);
	if (free_path)
		free(path);
	return pid;
}

int finish_connect(pid_t pid)
{
	if (pid == 0)
		return 0;

	while (waitpid(pid, NULL, 0) < 0) {
		if (errno != EINTR)
			return -1;
	}
	return 0;
}
Commit	Line	Data
731043fd	1	#include "git-compat-util.h"
f7192598	2	#include "cache.h"
41cb7488	3	#include "pkt-line.h"
b10d0ec7	4	#include "quote.h"
6abf5c0c	5	#include "refs.h"
15a1c012	6	#include "run-command.h"
6b62816c	7	#include "remote.h"
f7192598	8
96f1e58f	9	static char *server_capabilities;
211b5f9e	10
2718ff09 LT	11	static int check_ref(const char *name, int len, unsigned int flags)
	12	{
	13	if (!flags)
	14	return 1;
	15
c41e20b3	16	if (len < 5 \|\| memcmp(name, "refs/", 5))
2718ff09 LT	17	return 0;
	18
	19	/* Skip the "refs/" part */
	20	name += 5;
	21	len -= 5;
	22
	23	/* REF_NORMAL means that we don't want the magic fake tag refs */
	24	if ((flags & REF_NORMAL) && check_ref_format(name) < 0)
	25	return 0;
	26
	27	/* REF_HEADS means that we want regular branch heads */
	28	if ((flags & REF_HEADS) && !memcmp(name, "heads/", 6))
	29	return 1;
	30
	31	/* REF_TAGS means that we want tags */
	32	if ((flags & REF_TAGS) && !memcmp(name, "tags/", 5))
	33	return 1;
	34
	35	/* All type bits clear means that we are ok with anything */
	36	return !(flags & ~REF_NORMAL);
	37	}
	38
d1c133f5 LT	39	/*
	40	* Read all the refs from the other end
	41	*/
1a7141ff	42	struct ref get_remote_heads(int in, struct ref list,
2718ff09 LT	43	int nr_match, char **match,
2718ff09 LT	44	unsigned int flags)
d1c133f5 LT	45	{
	46	*list = NULL;
	47	for (;;) {
	48	struct ref *ref;
	49	unsigned char old_sha1[20];
	50	static char buffer[1000];
	51	char *name;
211b5f9e	52	int len, name_len;
d1c133f5 LT	53
	54	len = packet_read_line(in, buffer, sizeof(buffer));
	55	if (!len)
	56	break;
	57	if (buffer[len-1] == '\n')
	58	buffer[--len] = 0;
	59
	60	if (len < 42 \|\| get_sha1_hex(buffer, old_sha1) \|\| buffer[40] != ' ')
	61	die("protocol error: expected sha/ref, got '%s'", buffer);
	62	name = buffer + 41;
1a7141ff	63
211b5f9e JS	64	name_len = strlen(name);
	65	if (len != name_len + 41) {
	66	if (server_capabilities)
	67	free(server_capabilities);
9befac47	68	server_capabilities = xstrdup(name + name_len + 1);
211b5f9e JS	69	}
211b5f9e JS	70
2718ff09	71	if (!check_ref(name, name_len, flags))
cfee10a7	72	continue;
d1c133f5 LT	73	if (nr_match && !path_match(name, nr_match, match))
d1c133f5 LT	74	continue;
f88395ac	75	ref = xcalloc(1, sizeof(*ref) + len - 40);
e702496e	76	hashcpy(ref->old_sha1, old_sha1);
d1c133f5	77	memcpy(ref->name, buffer + 41, len - 40);
d1c133f5 LT	78	*list = ref;
	79	list = &ref->next;
	80	}
	81	return list;
	82	}
	83
211b5f9e JS	84	int server_supports(const char *feature)
211b5f9e JS	85	{
1f5881bb JS	86	return server_capabilities &&
1f5881bb JS	87	strstr(server_capabilities, feature) != NULL;
211b5f9e JS	88	}
211b5f9e JS	89
41cb7488 LT	90	int get_ack(int fd, unsigned char *result_sha1)
	91	{
	92	static char line[1000];
	93	int len = packet_read_line(fd, line, sizeof(line));
	94
	95	if (!len)
	96	die("git-fetch-pack: expected ACK/NAK, got EOF");
	97	if (line[len-1] == '\n')
	98	line[--len] = 0;
	99	if (!strcmp(line, "NAK"))
	100	return 0;
cc44c765	101	if (!prefixcmp(line, "ACK ")) {
c4c86f07 JS	102	if (!get_sha1_hex(line+4, result_sha1)) {
	103	if (strstr(line+45, "continue"))
	104	return 2;
41cb7488	105	return 1;
c4c86f07	106	}
41cb7488 LT	107	}
	108	die("git-fetch_pack: expected ACK/NAK, got '%s'", line);
	109	}
	110
013e7c7f LT	111	int path_match(const char path, int nr, char *match)
	112	{
	113	int i;
	114	int pathlen = strlen(path);
	115
	116	for (i = 0; i < nr; i++) {
	117	char *s = match[i];
	118	int len = strlen(s);
	119
	120	if (!len \|\| len > pathlen)
	121	continue;
	122	if (memcmp(path + pathlen - len, s, len))
	123	continue;
	124	if (pathlen > len && path[pathlen - len - 1] != '/')
	125	continue;
	126	*s = 0;
9546010b	127	return (i + 1);
013e7c7f LT	128	}
	129	return 0;
	130	}
	131
2386d658 LT	132	enum protocol {
	133	PROTO_LOCAL = 1,
	134	PROTO_SSH,
	135	PROTO_GIT,
	136	};
	137
	138	static enum protocol get_protocol(const char *name)
	139	{
	140	if (!strcmp(name, "ssh"))
	141	return PROTO_SSH;
	142	if (!strcmp(name, "git"))
	143	return PROTO_GIT;
c05186cc LT	144	if (!strcmp(name, "git+ssh"))
	145	return PROTO_SSH;
	146	if (!strcmp(name, "ssh+git"))
	147	return PROTO_SSH;
2386d658 LT	148	die("I don't handle protocol '%s'", name);
	149	}
	150
5ba88448 YH	151	#define STR_(s) # s
5ba88448 YH	152	#define STR(s) STR_(s)
2386d658	153
49744d63	154	#ifndef NO_IPV6
4c505f71	155
5ad312be JL	156	/*
	157	* Returns a connected socket() fd, or else die()s.
	158	*/
7841ce79	159	static int git_tcp_connect_sock(char *host, int flags)
2386d658	160	{
ac3bc6c1	161	int sockfd = -1, saved_errno = 0;
5ba88448	162	char colon, end;
554fe20d	163	const char *port = STR(DEFAULT_GIT_PORT);
5ba88448 YH	164	struct addrinfo hints, ai0, ai;
	165	int gai;
	166
	167	if (host[0] == '[') {
	168	end = strchr(host + 1, ']');
	169	if (end) {
	170	*end = 0;
	171	end++;
	172	host++;
	173	} else
	174	end = host;
	175	} else
	176	end = host;
	177	colon = strchr(end, ':');
	178
ce6f8e7e LT	179	if (colon) {
ce6f8e7e LT	180	*colon = 0;
5ba88448	181	port = colon + 1;
608d48b2 LT	182	if (!*port)
608d48b2 LT	183	port = "<none>";
ce6f8e7e	184	}
5ba88448 YH	185
	186	memset(&hints, 0, sizeof(hints));
	187	hints.ai_socktype = SOCK_STREAM;
	188	hints.ai_protocol = IPPROTO_TCP;
	189
7841ce79 MT	190	if (flags & CONNECT_VERBOSE)
	191	fprintf(stderr, "Looking up %s ... ", host);
	192
5ba88448 YH	193	gai = getaddrinfo(host, port, &hints, &ai);
5ba88448 YH	194	if (gai)
608d48b2	195	die("Unable to look up %s (port %s) (%s)", host, port, gai_strerror(gai));
5ba88448	196
7841ce79 MT	197	if (flags & CONNECT_VERBOSE)
	198	fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
	199
5ba88448	200	for (ai0 = ai; ai; ai = ai->ai_next) {
5ad312be JL	201	sockfd = socket(ai->ai_family,
5ad312be JL	202	ai->ai_socktype, ai->ai_protocol);
ac3bc6c1 PB	203	if (sockfd < 0) {
ac3bc6c1 PB	204	saved_errno = errno;
5ba88448	205	continue;
ac3bc6c1	206	}
5ba88448	207	if (connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
ac3bc6c1	208	saved_errno = errno;
5ba88448 YH	209	close(sockfd);
	210	sockfd = -1;
	211	continue;
2386d658	212	}
5ba88448	213	break;
2386d658 LT	214	}
2386d658 LT	215
5ba88448	216	freeaddrinfo(ai0);
2386d658	217
2386d658	218	if (sockfd < 0)
ac3bc6c1	219	die("unable to connect a socket (%s)", strerror(saved_errno));
5ba88448	220
7841ce79 MT	221	if (flags & CONNECT_VERBOSE)
	222	fprintf(stderr, "done.\n");
	223
5ad312be	224	return sockfd;
2386d658 LT	225	}
2386d658 LT	226
49744d63	227	#else /* NO_IPV6 */
4c505f71	228
5ad312be JL	229	/*
	230	* Returns a connected socket() fd, or else die()s.
	231	*/
7841ce79	232	static int git_tcp_connect_sock(char *host, int flags)
4c505f71	233	{
ac3bc6c1	234	int sockfd = -1, saved_errno = 0;
4c505f71 PA	235	char colon, end;
	236	char port = STR(DEFAULT_GIT_PORT), ep;
	237	struct hostent *he;
	238	struct sockaddr_in sa;
	239	char **ap;
	240	unsigned int nport;
	241
	242	if (host[0] == '[') {
	243	end = strchr(host + 1, ']');
	244	if (end) {
	245	*end = 0;
	246	end++;
	247	host++;
	248	} else
	249	end = host;
	250	} else
	251	end = host;
	252	colon = strchr(end, ':');
	253
	254	if (colon) {
	255	*colon = 0;
	256	port = colon + 1;
	257	}
	258
7841ce79 MT	259	if (flags & CONNECT_VERBOSE)
	260	fprintf(stderr, "Looking up %s ... ", host);
	261
4c505f71 PA	262	he = gethostbyname(host);
	263	if (!he)
	264	die("Unable to look up %s (%s)", host, hstrerror(h_errno));
	265	nport = strtoul(port, &ep, 10);
	266	if ( ep == port \|\| *ep ) {
	267	/* Not numeric */
	268	struct servent *se = getservbyname(port,"tcp");
	269	if ( !se )
	270	die("Unknown port %s\n", port);
	271	nport = se->s_port;
	272	}
	273
7841ce79 MT	274	if (flags & CONNECT_VERBOSE)
	275	fprintf(stderr, "done.\nConnecting to %s (port %s) ... ", host, port);
	276
4c505f71 PA	277	for (ap = he->h_addr_list; *ap; ap++) {
4c505f71 PA	278	sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
ac3bc6c1 PB	279	if (sockfd < 0) {
ac3bc6c1 PB	280	saved_errno = errno;
4c505f71	281	continue;
ac3bc6c1	282	}
4c505f71 PA	283
	284	memset(&sa, 0, sizeof sa);
	285	sa.sin_family = he->h_addrtype;
6573faff	286	sa.sin_port = htons(nport);
c6164218	287	memcpy(&sa.sin_addr, *ap, he->h_length);
4c505f71 PA	288
4c505f71 PA	289	if (connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
ac3bc6c1	290	saved_errno = errno;
4c505f71 PA	291	close(sockfd);
	292	sockfd = -1;
	293	continue;
	294	}
	295	break;
	296	}
	297
	298	if (sockfd < 0)
ac3bc6c1	299	die("unable to connect a socket (%s)", strerror(saved_errno));
4c505f71	300
7841ce79 MT	301	if (flags & CONNECT_VERBOSE)
	302	fprintf(stderr, "done.\n");
	303
5ad312be JL	304	return sockfd;
	305	}
	306
	307	#endif /* NO_IPV6 */
	308
	309
7841ce79	310	static void git_tcp_connect(int fd[2], char *host, int flags)
5ad312be	311	{
7841ce79	312	int sockfd = git_tcp_connect_sock(host, flags);
5ad312be	313
4c505f71	314	fd[0] = sockfd;
ec587fde	315	fd[1] = dup(sockfd);
4c505f71 PA	316	}
4c505f71 PA	317
4c505f71	318
96f1e58f DR	319	static char *git_proxy_command;
96f1e58f DR	320	static const char *rhost_name;
e814bc4d	321	static int rhost_len;
f8014776 PC	322
	323	static int git_proxy_command_options(const char var, const char value)
	324	{
e814bc4d	325	if (!strcmp(var, "core.gitproxy")) {
c3df8568 YH	326	const char *for_pos;
	327	int matchlen = -1;
	328	int hostlen;
	329
e814bc4d	330	if (git_proxy_command)
f8014776	331	return 0;
e814bc4d JH	332	/* [core]
	333	* ;# matches www.kernel.org as well
	334	* gitproxy = netcatter-1 for kernel.org
	335	* gitproxy = netcatter-2 for sample.xz
	336	* gitproxy = netcatter-default
	337	*/
c3df8568	338	for_pos = strstr(value, " for ");
e814bc4d JH	339	if (!for_pos)
	340	/* matches everybody */
	341	matchlen = strlen(value);
	342	else {
	343	hostlen = strlen(for_pos + 5);
	344	if (rhost_len < hostlen)
	345	matchlen = -1;
	346	else if (!strncmp(for_pos + 5,
	347	rhost_name + rhost_len - hostlen,
	348	hostlen) &&
	349	((rhost_len == hostlen) \|\|
	350	rhost_name[rhost_len - hostlen -1] == '.'))
	351	matchlen = for_pos - value;
	352	else
	353	matchlen = -1;
	354	}
	355	if (0 <= matchlen) {
	356	/* core.gitproxy = none for kernel.org */
	357	if (matchlen == 4 &&
	358	!memcmp(value, "none", 4))
	359	matchlen = 0;
	360	git_proxy_command = xmalloc(matchlen + 1);
	361	memcpy(git_proxy_command, value, matchlen);
	362	git_proxy_command[matchlen] = 0;
f8014776	363	}
e814bc4d	364	return 0;
f8014776 PC	365	}
	366
	367	return git_default_config(var, value);
	368	}
	369
e814bc4d	370	static int git_use_proxy(const char *host)
f8014776	371	{
e814bc4d JH	372	rhost_name = host;
e814bc4d JH	373	rhost_len = strlen(host);
f8014776 PC	374	git_proxy_command = getenv("GIT_PROXY_COMMAND");
f8014776 PC	375	git_config(git_proxy_command_options);
e814bc4d JH	376	rhost_name = NULL;
e814bc4d JH	377	return (git_proxy_command && *git_proxy_command);
f8014776 PC	378	}
f8014776 PC	379
c78963d2	380	static void git_proxy_connect(int fd[2], char *host)
f8014776	381	{
554fe20d	382	const char *port = STR(DEFAULT_GIT_PORT);
f8014776	383	char colon, end;
15a1c012 SP	384	const char *argv[4];
15a1c012 SP	385	struct child_process proxy;
f8014776 PC	386
	387	if (host[0] == '[') {
	388	end = strchr(host + 1, ']');
	389	if (end) {
	390	*end = 0;
	391	end++;
	392	host++;
	393	} else
	394	end = host;
	395	} else
	396	end = host;
	397	colon = strchr(end, ':');
	398
	399	if (colon) {
	400	*colon = 0;
	401	port = colon + 1;
	402	}
	403
15a1c012 SP	404	argv[0] = git_proxy_command;
	405	argv[1] = host;
	406	argv[2] = port;
	407	argv[3] = NULL;
	408	memset(&proxy, 0, sizeof(proxy));
	409	proxy.argv = argv;
	410	proxy.in = -1;
	411	proxy.out = -1;
	412	if (start_command(&proxy))
	413	die("cannot start proxy %s", argv[0]);
	414	fd[0] = proxy.out; /* read from proxy stdout */
	415	fd[1] = proxy.in; /* write to proxy stdin */
f8014776 PC	416	}
f8014776 PC	417
0f503d77 CC	418	#define MAX_CMD_LEN 1024
0f503d77 CC	419
f7192598	420	/*
f42a5c4e FBH	421	* This returns 0 if the transport protocol does not need fork(2),
	422	* or a process id if it does. Once done, finish the connection
	423	* with finish_connect() with the value returned from this function
	424	* (it is safe to call finish_connect() with 0 to support the former
	425	* case).
	426	*
	427	* Does not return a negative value on error; it just dies.
f7192598	428	*/
7841ce79	429	pid_t git_connect(int fd[2], char url, const char prog, int flags)
f7192598	430	{
faea9ccb	431	char host, path = url;
356bece0 YH	432	char *end;
356bece0 YH	433	int c;
f7192598 LT	434	int pipefd[2][2];
f7192598 LT	435	pid_t pid;
faea9ccb	436	enum protocol protocol = PROTO_LOCAL;
da2a95b2	437	int free_path = 0;
faea9ccb	438
f0b7367c JH	439	/* Without this we cannot rely on waitpid() to tell
	440	* what happened to our children.
	441	*/
	442	signal(SIGCHLD, SIG_DFL);
	443
faea9ccb AE	444	host = strstr(url, "://");
	445	if(host) {
	446	*host = '\0';
	447	protocol = get_protocol(url);
	448	host += 3;
356bece0 YH	449	c = '/';
356bece0 YH	450	} else {
f7192598	451	host = url;
356bece0 YH	452	c = ':';
	453	}
	454
	455	if (host[0] == '[') {
	456	end = strchr(host + 1, ']');
	457	if (end) {
	458	*end = 0;
	459	end++;
	460	host++;
	461	} else
	462	end = host;
	463	} else
	464	end = host;
	465
	466	path = strchr(end, c);
	467	if (c == ':') {
	468	if (path) {
faea9ccb	469	protocol = PROTO_SSH;
356bece0 YH	470	*path++ = '\0';
	471	} else
	472	path = host;
f7192598	473	}
2386d658	474
faea9ccb AE	475	if (!path \|\| !*path)
	476	die("No path specified. See 'man git-pull' for valid url syntax");
	477
	478	/*
	479	* null-terminate hostname and point path to ~ for URL's like this:
	480	* ssh://host.xz/~user/repo
	481	*/
	482	if (protocol != PROTO_LOCAL && host != url) {
	483	char *ptr = path;
	484	if (path[1] == '~')
	485	path++;
da2a95b2	486	else {
9befac47	487	path = xstrdup(ptr);
da2a95b2 SH	488	free_path = 1;
da2a95b2 SH	489	}
faea9ccb AE	490
	491	*ptr = '\0';
	492	}
	493
f8014776	494	if (protocol == PROTO_GIT) {
5ad312be JL	495	/* These underlying connection commands die() if they
	496	* cannot connect.
	497	*/
9befac47	498	char *target_host = xstrdup(host);
e814bc4d	499	if (git_use_proxy(host))
c78963d2	500	git_proxy_connect(fd, host);
da2a95b2	501	else
7841ce79	502	git_tcp_connect(fd, host, flags);
5ad312be JL	503	/*
	504	* Separate original protocol components prog and path
	505	* from extended components with a NUL byte.
	506	*/
	507	packet_write(fd[1],
	508	"%s %s%chost=%s%c",
	509	prog, path, 0,
	510	target_host, 0);
	511	free(target_host);
da2a95b2 SH	512	if (free_path)
da2a95b2 SH	513	free(path);
5ad312be	514	return 0;
f8014776	515	}
2386d658	516
f7192598 LT	517	if (pipe(pipefd[0]) < 0 \|\| pipe(pipefd[1]) < 0)
	518	die("unable to create pipe pair for communication");
	519	pid = fork();
c9bc159d PD	520	if (pid < 0)
c9bc159d PD	521	die("unable to fork");
f7192598	522	if (!pid) {
0f503d77 CC	523	char command[MAX_CMD_LEN];
	524	char *posn = command;
	525	int size = MAX_CMD_LEN;
	526	int of = 0;
	527
	528	of \|= add_to_string(&posn, &size, prog, 0);
	529	of \|= add_to_string(&posn, &size, " ", 0);
	530	of \|= add_to_string(&posn, &size, path, 1);
	531
	532	if (of)
	533	die("command line too long");
	534
f7192598 LT	535	dup2(pipefd[1][0], 0);
	536	dup2(pipefd[0][1], 1);
	537	close(pipefd[0][0]);
	538	close(pipefd[0][1]);
	539	close(pipefd[1][0]);
	540	close(pipefd[1][1]);
4852f723	541	if (protocol == PROTO_SSH) {
c7c81b3a JR	542	const char ssh, ssh_basename;
	543	ssh = getenv("GIT_SSH");
	544	if (!ssh) ssh = "ssh";
	545	ssh_basename = strrchr(ssh, '/');
4852f723 MS	546	if (!ssh_basename)
	547	ssh_basename = ssh;
	548	else
	549	ssh_basename++;
	550	execlp(ssh, ssh_basename, host, command, NULL);
	551	}
016fb48b MD	552	else {
	553	unsetenv(ALTERNATE_DB_ENVIRONMENT);
	554	unsetenv(DB_ENVIRONMENT);
	555	unsetenv(GIT_DIR_ENVIRONMENT);
	556	unsetenv(GRAFT_ENVIRONMENT);
	557	unsetenv(INDEX_ENVIRONMENT);
f7192598	558	execlp("sh", "sh", "-c", command, NULL);
016fb48b	559	}
f7192598	560	die("exec failed");
016fb48b	561	}
f7192598 LT	562	fd[0] = pipefd[0][0];
	563	fd[1] = pipefd[1][1];
	564	close(pipefd[0][1]);
	565	close(pipefd[1][0]);
da2a95b2 SH	566	if (free_path)
da2a95b2 SH	567	free(path);
f7192598 LT	568	return pid;
	569	}
	570
	571	int finish_connect(pid_t pid)
	572	{
f42a5c4e FBH	573	if (pid == 0)
	574	return 0;
	575
53e1a761	576	while (waitpid(pid, NULL, 0) < 0) {
f7192598	577	if (errno != EINTR)
53e1a761	578	return -1;
f7192598	579	}
53e1a761	580	return 0;
f7192598	581	}