kernel
/
git
mirror of https://git.kernel.org/pub/scm/git/git.git
1
0
Fork 0
Code Releases Activity
git/connect.c

812 lines
17 KiB
C
Raw Blame History

#include "git-compat-util.h"
#include "cache.h"
#include "pkt-line.h"
#include "quote.h"
#include "refs.h"
#include <sys/wait.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <signal.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 (!strncmp(line, "ACK ", 4)) {
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;
}
struct refspec {
char *src;
char *dst;
char force;
};
/*
* A:B means fast forward remote B with local A.
* +A:B means overwrite remote B with local A.
* +A is a shorthand for +A:A.
* A is a shorthand for A:A.
* :B means delete remote B.
*/
static struct refspec *parse_ref_spec(int nr_refspec, char **refspec)
{
int i;
struct refspec *rs = xcalloc(sizeof(*rs), (nr_refspec + 1));
for (i = 0; i < nr_refspec; i++) {
char *sp, *dp, *ep;
sp = refspec[i];
if (*sp == '+') {
rs[i].force = 1;
sp++;
}
ep = strchr(sp, ':');
if (ep) {
dp = ep + 1;
*ep = 0;
}
else
dp = sp;
rs[i].src = sp;
rs[i].dst = dp;
}
rs[nr_refspec].src = rs[nr_refspec].dst = NULL;
return rs;
}
static int count_refspec_match(const char *pattern,
struct ref *refs,
struct ref **matched_ref)
{
int patlen = strlen(pattern);
struct ref *matched_weak = NULL;
struct ref *matched = NULL;
int weak_match = 0;
int match = 0;
for (weak_match = match = 0; refs; refs = refs->next) {
char *name = refs->name;
int namelen = strlen(name);
int weak_match;
if (namelen < patlen ||
memcmp(name + namelen - patlen, pattern, patlen))
continue;
if (namelen != patlen && name[namelen - patlen - 1] != '/')
continue;
/* A match is "weak" if it is with refs outside
* heads or tags, and did not specify the pattern
* in full (e.g. "refs/remotes/origin/master") or at
* least from the toplevel (e.g. "remotes/origin/master");
* otherwise "git push $URL master" would result in
* ambiguity between remotes/origin/master and heads/master
* at the remote site.
*/
if (namelen != patlen &&
patlen != namelen - 5 &&
strncmp(name, "refs/heads/", 11) &&
strncmp(name, "refs/tags/", 10)) {
/* We want to catch the case where only weak
* matches are found and there are multiple
* matches, and where more than one strong
* matches are found, as ambiguous. One
* strong match with zero or more weak matches
* are acceptable as a unique match.
*/
matched_weak = refs;
weak_match++;
}
else {
matched = refs;
match++;
}
}
if (!matched) {
*matched_ref = matched_weak;
return weak_match;
}
else {
*matched_ref = matched;
return match;
}
}
static void link_dst_tail(struct ref *ref, struct ref ***tail)
{
**tail = ref;
*tail = &ref->next;
**tail = NULL;
}
static struct ref *try_explicit_object_name(const char *name)
{
unsigned char sha1[20];
struct ref *ref;
int len;
if (!*name) {
ref = xcalloc(1, sizeof(*ref) + 20);
strcpy(ref->name, "(delete)");
hashclr(ref->new_sha1);
return ref;
}
if (get_sha1(name, sha1))
return NULL;
len = strlen(name) + 1;
ref = xcalloc(1, sizeof(*ref) + len);
memcpy(ref->name, name, len);
hashcpy(ref->new_sha1, sha1);
return ref;
}
static int match_explicit_refs(struct ref *src, struct ref *dst,
struct ref ***dst_tail, struct refspec *rs)
{
int i, errs;
for (i = errs = 0; rs[i].src; i++) {
struct ref *matched_src, *matched_dst;
matched_src = matched_dst = NULL;
switch (count_refspec_match(rs[i].src, src, &matched_src)) {
case 1:
break;
case 0:
/* The source could be in the get_sha1() format
* not a reference name. :refs/other is a
* way to delete 'other' ref at the remote end.
*/
matched_src = try_explicit_object_name(rs[i].src);
if (matched_src)
break;
errs = 1;
error("src refspec %s does not match any.",
rs[i].src);
break;
default:
errs = 1;
error("src refspec %s matches more than one.",
rs[i].src);
break;
}
switch (count_refspec_match(rs[i].dst, dst, &matched_dst)) {
case 1:
break;
case 0:
if (!memcmp(rs[i].dst, "refs/", 5)) {
int len = strlen(rs[i].dst) + 1;
matched_dst = xcalloc(1, sizeof(*dst) + len);
memcpy(matched_dst->name, rs[i].dst, len);
link_dst_tail(matched_dst, dst_tail);
}
else if (!strcmp(rs[i].src, rs[i].dst) &&
matched_src) {
/* pushing "master:master" when
* remote does not have master yet.
*/
int len = strlen(matched_src->name) + 1;
matched_dst = xcalloc(1, sizeof(*dst) + len);
memcpy(matched_dst->name, matched_src->name,
len);
link_dst_tail(matched_dst, dst_tail);
}
else {
errs = 1;
error("dst refspec %s does not match any "
"existing ref on the remote and does "
"not start with refs/.", rs[i].dst);
}
break;
default:
errs = 1;
error("dst refspec %s matches more than one.",
rs[i].dst);
break;
}
if (errs)
continue;
if (matched_dst->peer_ref) {
errs = 1;
error("dst ref %s receives from more than one src.",
matched_dst->name);
}
else {
matched_dst->peer_ref = matched_src;
matched_dst->force = rs[i].force;
}
}
return -errs;
}
static struct ref *find_ref_by_name(struct ref *list, const char *name)
{
for ( ; list; list = list->next)
if (!strcmp(list->name, name))
return list;
return NULL;
}
int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail,
int nr_refspec, char **refspec, int all)
{
struct refspec *rs = parse_ref_spec(nr_refspec, refspec);
if (nr_refspec)
return match_explicit_refs(src, dst, dst_tail, rs);
/* pick the remainder */
for ( ; src; src = src->next) {
struct ref *dst_peer;
if (src->peer_ref)
continue;
dst_peer = find_ref_by_name(dst, src->name);
if ((dst_peer && dst_peer->peer_ref) || (!dst_peer && !all))
continue;
if (!dst_peer) {
/* Create a new one and link it */
int len = strlen(src->name) + 1;
dst_peer = xcalloc(1, sizeof(*dst_peer) + len);
memcpy(dst_peer->name, src->name, len);
hashcpy(dst_peer->new_sha1, src->new_sha1);
link_dst_tail(dst_peer, dst_tail);
}
dst_peer->peer_ref = src;
}
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 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;
}
memset(&hints, 0, sizeof(hints));
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
gai = getaddrinfo(host, port, &hints, &ai);
if (gai)
die("Unable to look up %s (%s)", host, gai_strerror(gai));
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));
return sockfd;
}
#else /* NO_IPV6 */
/*
* Returns a connected socket() fd, or else die()s.
*/
static int git_tcp_connect_sock(char *host)
{
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;
}
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;
}
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));
return sockfd;
}
#endif /* NO_IPV6 */
static void git_tcp_connect(int fd[2], char *host)
{
int sockfd = git_tcp_connect_sock(host);
fd[0] = sockfd;
fd[1] = 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;
int pipefd[2][2];
pid_t pid;
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 (pipe(pipefd[0]) < 0 || pipe(pipefd[1]) < 0)
die("unable to create pipe pair for communication");
pid = fork();
if (!pid) {
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]);
execlp(git_proxy_command, git_proxy_command, host, port, NULL);
die("exec failed");
}
if (pid < 0)
die("fork failed");
fd[0] = pipefd[0][0];
fd[1] = pipefd[1][1];
close(pipefd[0][1]);
close(pipefd[1][0]);
}
#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)
{
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);
/*
* 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;
}
View Git Blame Copy Permalink