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-rw-r--r--connect.c801
1 files changed, 801 insertions, 0 deletions
diff --git a/connect.c b/connect.c
new file mode 100644
index 0000000..da89c9c
--- /dev/null
+++ b/connect.c
@@ -0,0 +1,801 @@
+#include "git-compat-util.h"
+#include "cache.h"
+#include "pkt-line.h"
+#include "quote.h"
+#include "refs.h"
+#include "run-command.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;
+}
+
+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 &&
+ prefixcmp(name, "refs/heads/") &&
+ prefixcmp(name, "refs/tags/")) {
+ /* 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;
+ if (!*port)
+ port = "<none>";
+ }
+
+ 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 (port %s) (%s)", host, port, 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] = 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)
+{
+ 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;
+}
generated by cgit v0.10.2-6-g49f6 at 2024-04-26 01:05:01 (GMT)