git/connect.c
Ævar Arnfjörð Bjarmason f36d4f8316 ls-remote & transport API: release "struct transport_ls_refs_options"
Fix a memory leak in codepaths that use the "struct
transport_ls_refs_options" API. Since the introduction of the struct
in 39835409d1 (connect, transport: encapsulate arg in struct,
2021-02-05) the caller has been responsible for freeing it.

That commit in turn migrated code originally added in
402c47d939 (clone: send ref-prefixes when using protocol v2,
2018-07-20) and b4be74105f (ls-remote: pass ref prefixes when
requesting a remote's refs, 2018-03-15). Only some of those codepaths
were releasing the allocated resources of the struct, now all of them
will.

Mark the "t/t5511-refspec.sh" test as passing when git is compiled
with SANITIZE=leak. They'll now be listed as running under the
"GIT_TEST_PASSING_SANITIZE_LEAK=true" test mode (the "linux-leaks" CI
target). Previously 24/47 tests would fail.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-02-06 18:02:34 -08:00

1461 lines
36 KiB
C

#include "git-compat-util.h"
#include "cache.h"
#include "config.h"
#include "pkt-line.h"
#include "quote.h"
#include "refs.h"
#include "run-command.h"
#include "remote.h"
#include "connect.h"
#include "url.h"
#include "string-list.h"
#include "oid-array.h"
#include "transport.h"
#include "strbuf.h"
#include "version.h"
#include "protocol.h"
#include "alias.h"
static char *server_capabilities_v1;
static struct strvec server_capabilities_v2 = STRVEC_INIT;
static const char *next_server_feature_value(const char *feature, int *len, int *offset);
static int check_ref(const char *name, unsigned int flags)
{
if (!flags)
return 1;
if (!skip_prefix(name, "refs/", &name))
return 0;
/* REF_NORMAL means that we don't want the magic fake tag refs */
if ((flags & REF_NORMAL) && check_refname_format(name, 0))
return 0;
/* REF_HEADS means that we want regular branch heads */
if ((flags & REF_HEADS) && starts_with(name, "heads/"))
return 1;
/* REF_TAGS means that we want tags */
if ((flags & REF_TAGS) && starts_with(name, "tags/"))
return 1;
/* All type bits clear means that we are ok with anything */
return !(flags & ~REF_NORMAL);
}
int check_ref_type(const struct ref *ref, int flags)
{
return check_ref(ref->name, flags);
}
static NORETURN void die_initial_contact(int unexpected)
{
/*
* A hang-up after seeing some response from the other end
* means that it is unexpected, as we know the other end is
* willing to talk to us. A hang-up before seeing any
* response does not necessarily mean an ACL problem, though.
*/
if (unexpected)
die(_("the remote end hung up upon initial contact"));
else
die(_("Could not read from remote repository.\n\n"
"Please make sure you have the correct access rights\n"
"and the repository exists."));
}
/* Checks if the server supports the capability 'c' */
int server_supports_v2(const char *c, int die_on_error)
{
int i;
for (i = 0; i < server_capabilities_v2.nr; i++) {
const char *out;
if (skip_prefix(server_capabilities_v2.v[i], c, &out) &&
(!*out || *out == '='))
return 1;
}
if (die_on_error)
die(_("server doesn't support '%s'"), c);
return 0;
}
int server_feature_v2(const char *c, const char **v)
{
int i;
for (i = 0; i < server_capabilities_v2.nr; i++) {
const char *out;
if (skip_prefix(server_capabilities_v2.v[i], c, &out) &&
(*out == '=')) {
*v = out + 1;
return 1;
}
}
return 0;
}
int server_supports_feature(const char *c, const char *feature,
int die_on_error)
{
int i;
for (i = 0; i < server_capabilities_v2.nr; i++) {
const char *out;
if (skip_prefix(server_capabilities_v2.v[i], c, &out) &&
(!*out || *(out++) == '=')) {
if (parse_feature_request(out, feature))
return 1;
else
break;
}
}
if (die_on_error)
die(_("server doesn't support feature '%s'"), feature);
return 0;
}
static void process_capabilities_v2(struct packet_reader *reader)
{
while (packet_reader_read(reader) == PACKET_READ_NORMAL)
strvec_push(&server_capabilities_v2, reader->line);
if (reader->status != PACKET_READ_FLUSH)
die(_("expected flush after capabilities"));
}
enum protocol_version discover_version(struct packet_reader *reader)
{
enum protocol_version version = protocol_unknown_version;
/*
* Peek the first line of the server's response to
* determine the protocol version the server is speaking.
*/
switch (packet_reader_peek(reader)) {
case PACKET_READ_EOF:
die_initial_contact(0);
case PACKET_READ_FLUSH:
case PACKET_READ_DELIM:
case PACKET_READ_RESPONSE_END:
version = protocol_v0;
break;
case PACKET_READ_NORMAL:
version = determine_protocol_version_client(reader->line);
break;
}
switch (version) {
case protocol_v2:
process_capabilities_v2(reader);
break;
case protocol_v1:
/* Read the peeked version line */
packet_reader_read(reader);
break;
case protocol_v0:
break;
case protocol_unknown_version:
BUG("unknown protocol version");
}
trace2_data_intmax("transfer", NULL, "negotiated-version", version);
return version;
}
static void parse_one_symref_info(struct string_list *symref, const char *val, int len)
{
char *sym, *target;
struct string_list_item *item;
if (!len)
return; /* just "symref" */
/* e.g. "symref=HEAD:refs/heads/master" */
sym = xmemdupz(val, len);
target = strchr(sym, ':');
if (!target)
/* just "symref=something" */
goto reject;
*(target++) = '\0';
if (check_refname_format(sym, REFNAME_ALLOW_ONELEVEL) ||
check_refname_format(target, REFNAME_ALLOW_ONELEVEL))
/* "symref=bogus:pair */
goto reject;
item = string_list_append_nodup(symref, sym);
item->util = target;
return;
reject:
free(sym);
return;
}
static void annotate_refs_with_symref_info(struct ref *ref)
{
struct string_list symref = STRING_LIST_INIT_DUP;
int offset = 0;
while (1) {
int len;
const char *val;
val = next_server_feature_value("symref", &len, &offset);
if (!val)
break;
parse_one_symref_info(&symref, val, len);
}
string_list_sort(&symref);
for (; ref; ref = ref->next) {
struct string_list_item *item;
item = string_list_lookup(&symref, ref->name);
if (!item)
continue;
ref->symref = xstrdup((char *)item->util);
}
string_list_clear(&symref, 0);
}
static void process_capabilities(struct packet_reader *reader, int *linelen)
{
const char *feat_val;
int feat_len;
const char *line = reader->line;
int nul_location = strlen(line);
if (nul_location == *linelen)
return;
server_capabilities_v1 = xstrdup(line + nul_location + 1);
*linelen = nul_location;
feat_val = server_feature_value("object-format", &feat_len);
if (feat_val) {
char *hash_name = xstrndup(feat_val, feat_len);
int hash_algo = hash_algo_by_name(hash_name);
if (hash_algo != GIT_HASH_UNKNOWN)
reader->hash_algo = &hash_algos[hash_algo];
free(hash_name);
} else {
reader->hash_algo = &hash_algos[GIT_HASH_SHA1];
}
}
static int process_dummy_ref(const struct packet_reader *reader)
{
const char *line = reader->line;
struct object_id oid;
const char *name;
if (parse_oid_hex_algop(line, &oid, &name, reader->hash_algo))
return 0;
if (*name != ' ')
return 0;
name++;
return oideq(null_oid(), &oid) && !strcmp(name, "capabilities^{}");
}
static void check_no_capabilities(const char *line, int len)
{
if (strlen(line) != len)
warning(_("ignoring capabilities after first line '%s'"),
line + strlen(line));
}
static int process_ref(const struct packet_reader *reader, int len,
struct ref ***list, unsigned int flags,
struct oid_array *extra_have)
{
const char *line = reader->line;
struct object_id old_oid;
const char *name;
if (parse_oid_hex_algop(line, &old_oid, &name, reader->hash_algo))
return 0;
if (*name != ' ')
return 0;
name++;
if (extra_have && !strcmp(name, ".have")) {
oid_array_append(extra_have, &old_oid);
} else if (!strcmp(name, "capabilities^{}")) {
die(_("protocol error: unexpected capabilities^{}"));
} else if (check_ref(name, flags)) {
struct ref *ref = alloc_ref(name);
oidcpy(&ref->old_oid, &old_oid);
**list = ref;
*list = &ref->next;
}
check_no_capabilities(line, len);
return 1;
}
static int process_shallow(const struct packet_reader *reader, int len,
struct oid_array *shallow_points)
{
const char *line = reader->line;
const char *arg;
struct object_id old_oid;
if (!skip_prefix(line, "shallow ", &arg))
return 0;
if (get_oid_hex_algop(arg, &old_oid, reader->hash_algo))
die(_("protocol error: expected shallow sha-1, got '%s'"), arg);
if (!shallow_points)
die(_("repository on the other end cannot be shallow"));
oid_array_append(shallow_points, &old_oid);
check_no_capabilities(line, len);
return 1;
}
enum get_remote_heads_state {
EXPECTING_FIRST_REF = 0,
EXPECTING_REF,
EXPECTING_SHALLOW,
EXPECTING_DONE,
};
/*
* Read all the refs from the other end
*/
struct ref **get_remote_heads(struct packet_reader *reader,
struct ref **list, unsigned int flags,
struct oid_array *extra_have,
struct oid_array *shallow_points)
{
struct ref **orig_list = list;
int len = 0;
enum get_remote_heads_state state = EXPECTING_FIRST_REF;
*list = NULL;
while (state != EXPECTING_DONE) {
switch (packet_reader_read(reader)) {
case PACKET_READ_EOF:
die_initial_contact(1);
case PACKET_READ_NORMAL:
len = reader->pktlen;
break;
case PACKET_READ_FLUSH:
state = EXPECTING_DONE;
break;
case PACKET_READ_DELIM:
case PACKET_READ_RESPONSE_END:
die(_("invalid packet"));
}
switch (state) {
case EXPECTING_FIRST_REF:
process_capabilities(reader, &len);
if (process_dummy_ref(reader)) {
state = EXPECTING_SHALLOW;
break;
}
state = EXPECTING_REF;
/* fallthrough */
case EXPECTING_REF:
if (process_ref(reader, len, &list, flags, extra_have))
break;
state = EXPECTING_SHALLOW;
/* fallthrough */
case EXPECTING_SHALLOW:
if (process_shallow(reader, len, shallow_points))
break;
die(_("protocol error: unexpected '%s'"), reader->line);
case EXPECTING_DONE:
break;
}
}
annotate_refs_with_symref_info(*orig_list);
return list;
}
/* Returns 1 when a valid ref has been added to `list`, 0 otherwise */
static int process_ref_v2(struct packet_reader *reader, struct ref ***list,
const char **unborn_head_target)
{
int ret = 1;
int i = 0;
struct object_id old_oid;
struct ref *ref;
struct string_list line_sections = STRING_LIST_INIT_DUP;
const char *end;
const char *line = reader->line;
/*
* Ref lines have a number of fields which are space deliminated. The
* first field is the OID of the ref. The second field is the ref
* name. Subsequent fields (symref-target and peeled) are optional and
* don't have a particular order.
*/
if (string_list_split(&line_sections, line, ' ', -1) < 2) {
ret = 0;
goto out;
}
if (!strcmp("unborn", line_sections.items[i].string)) {
i++;
if (unborn_head_target &&
!strcmp("HEAD", line_sections.items[i++].string)) {
/*
* Look for the symref target (if any). If found,
* return it to the caller.
*/
for (; i < line_sections.nr; i++) {
const char *arg = line_sections.items[i].string;
if (skip_prefix(arg, "symref-target:", &arg)) {
*unborn_head_target = xstrdup(arg);
break;
}
}
}
goto out;
}
if (parse_oid_hex_algop(line_sections.items[i++].string, &old_oid, &end, reader->hash_algo) ||
*end) {
ret = 0;
goto out;
}
ref = alloc_ref(line_sections.items[i++].string);
memcpy(ref->old_oid.hash, old_oid.hash, reader->hash_algo->rawsz);
**list = ref;
*list = &ref->next;
for (; i < line_sections.nr; i++) {
const char *arg = line_sections.items[i].string;
if (skip_prefix(arg, "symref-target:", &arg))
ref->symref = xstrdup(arg);
if (skip_prefix(arg, "peeled:", &arg)) {
struct object_id peeled_oid;
char *peeled_name;
struct ref *peeled;
if (parse_oid_hex_algop(arg, &peeled_oid, &end,
reader->hash_algo) || *end) {
ret = 0;
goto out;
}
peeled_name = xstrfmt("%s^{}", ref->name);
peeled = alloc_ref(peeled_name);
memcpy(peeled->old_oid.hash, peeled_oid.hash,
reader->hash_algo->rawsz);
**list = peeled;
*list = &peeled->next;
free(peeled_name);
}
}
out:
string_list_clear(&line_sections, 0);
return ret;
}
void check_stateless_delimiter(int stateless_rpc,
struct packet_reader *reader,
const char *error)
{
if (!stateless_rpc)
return; /* not in stateless mode, no delimiter expected */
if (packet_reader_read(reader) != PACKET_READ_RESPONSE_END)
die("%s", error);
}
struct ref **get_remote_refs(int fd_out, struct packet_reader *reader,
struct ref **list, int for_push,
struct transport_ls_refs_options *transport_options,
const struct string_list *server_options,
int stateless_rpc)
{
int i;
const char *hash_name;
struct strvec *ref_prefixes = transport_options ?
&transport_options->ref_prefixes : NULL;
const char **unborn_head_target = transport_options ?
&transport_options->unborn_head_target : NULL;
*list = NULL;
if (server_supports_v2("ls-refs", 1))
packet_write_fmt(fd_out, "command=ls-refs\n");
if (server_supports_v2("agent", 0))
packet_write_fmt(fd_out, "agent=%s", git_user_agent_sanitized());
if (server_feature_v2("object-format", &hash_name)) {
int hash_algo = hash_algo_by_name(hash_name);
if (hash_algo == GIT_HASH_UNKNOWN)
die(_("unknown object format '%s' specified by server"), hash_name);
reader->hash_algo = &hash_algos[hash_algo];
packet_write_fmt(fd_out, "object-format=%s", reader->hash_algo->name);
} else {
reader->hash_algo = &hash_algos[GIT_HASH_SHA1];
}
if (server_options && server_options->nr &&
server_supports_v2("server-option", 1))
for (i = 0; i < server_options->nr; i++)
packet_write_fmt(fd_out, "server-option=%s",
server_options->items[i].string);
packet_delim(fd_out);
/* When pushing we don't want to request the peeled tags */
if (!for_push)
packet_write_fmt(fd_out, "peel\n");
packet_write_fmt(fd_out, "symrefs\n");
if (server_supports_feature("ls-refs", "unborn", 0))
packet_write_fmt(fd_out, "unborn\n");
for (i = 0; ref_prefixes && i < ref_prefixes->nr; i++) {
packet_write_fmt(fd_out, "ref-prefix %s\n",
ref_prefixes->v[i]);
}
packet_flush(fd_out);
/* Process response from server */
while (packet_reader_read(reader) == PACKET_READ_NORMAL) {
if (!process_ref_v2(reader, &list, unborn_head_target))
die(_("invalid ls-refs response: %s"), reader->line);
}
if (reader->status != PACKET_READ_FLUSH)
die(_("expected flush after ref listing"));
check_stateless_delimiter(stateless_rpc, reader,
_("expected response end packet after ref listing"));
return list;
}
const char *parse_feature_value(const char *feature_list, const char *feature, int *lenp, int *offset)
{
int len;
if (!feature_list)
return NULL;
len = strlen(feature);
if (offset)
feature_list += *offset;
while (*feature_list) {
const char *found = strstr(feature_list, feature);
if (!found)
return NULL;
if (feature_list == found || isspace(found[-1])) {
const char *value = found + len;
/* feature with no value (e.g., "thin-pack") */
if (!*value || isspace(*value)) {
if (lenp)
*lenp = 0;
if (offset)
*offset = found + len - feature_list;
return value;
}
/* feature with a value (e.g., "agent=git/1.2.3") */
else if (*value == '=') {
int end;
value++;
end = strcspn(value, " \t\n");
if (lenp)
*lenp = end;
if (offset)
*offset = value + end - feature_list;
return value;
}
/*
* otherwise we matched a substring of another feature;
* keep looking
*/
}
feature_list = found + 1;
}
return NULL;
}
int server_supports_hash(const char *desired, int *feature_supported)
{
int offset = 0;
int len;
const char *hash;
hash = next_server_feature_value("object-format", &len, &offset);
if (feature_supported)
*feature_supported = !!hash;
if (!hash) {
hash = hash_algos[GIT_HASH_SHA1].name;
len = strlen(hash);
}
while (hash) {
if (!xstrncmpz(desired, hash, len))
return 1;
hash = next_server_feature_value("object-format", &len, &offset);
}
return 0;
}
int parse_feature_request(const char *feature_list, const char *feature)
{
return !!parse_feature_value(feature_list, feature, NULL, NULL);
}
static const char *next_server_feature_value(const char *feature, int *len, int *offset)
{
return parse_feature_value(server_capabilities_v1, feature, len, offset);
}
const char *server_feature_value(const char *feature, int *len)
{
return parse_feature_value(server_capabilities_v1, feature, len, NULL);
}
int server_supports(const char *feature)
{
return !!server_feature_value(feature, NULL);
}
enum protocol {
PROTO_LOCAL = 1,
PROTO_FILE,
PROTO_SSH,
PROTO_GIT
};
int url_is_local_not_ssh(const char *url)
{
const char *colon = strchr(url, ':');
const char *slash = strchr(url, '/');
return !colon || (slash && slash < colon) ||
(has_dos_drive_prefix(url) && is_valid_path(url));
}
static const char *prot_name(enum protocol protocol)
{
switch (protocol) {
case PROTO_LOCAL:
case PROTO_FILE:
return "file";
case PROTO_SSH:
return "ssh";
case PROTO_GIT:
return "git";
default:
return "unknown protocol";
}
}
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")) /* deprecated - do not use */
return PROTO_SSH;
if (!strcmp(name, "ssh+git")) /* deprecated - do not use */
return PROTO_SSH;
if (!strcmp(name, "file"))
return PROTO_FILE;
die(_("protocol '%s' is not supported"), name);
}
static char *host_end(char **hoststart, int removebrackets)
{
char *host = *hoststart;
char *end;
char *start = strstr(host, "@[");
if (start)
start++; /* Jump over '@' */
else
start = host;
if (start[0] == '[') {
end = strchr(start + 1, ']');
if (end) {
if (removebrackets) {
*end = 0;
memmove(start, start + 1, end - start);
end++;
}
} else
end = host;
} else
end = host;
return end;
}
#define STR_(s) # s
#define STR(s) STR_(s)
static void get_host_and_port(char **host, const char **port)
{
char *colon, *end;
end = host_end(host, 1);
colon = strchr(end, ':');
if (colon) {
long portnr = strtol(colon + 1, &end, 10);
if (end != colon + 1 && *end == '\0' && 0 <= portnr && portnr < 65536) {
*colon = 0;
*port = colon + 1;
} else if (!colon[1]) {
*colon = 0;
}
}
}
static void enable_keepalive(int sockfd)
{
int ka = 1;
if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &ka, sizeof(ka)) < 0)
error_errno(_("unable to set SO_KEEPALIVE on socket"));
}
#ifndef NO_IPV6
static const char *ai_name(const struct addrinfo *ai)
{
static char addr[NI_MAXHOST];
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, addr, sizeof(addr), NULL, 0,
NI_NUMERICHOST) != 0)
xsnprintf(addr, sizeof(addr), "(unknown)");
return addr;
}
/*
* Returns a connected socket() fd, or else die()s.
*/
static int git_tcp_connect_sock(char *host, int flags)
{
struct strbuf error_message = STRBUF_INIT;
int sockfd = -1;
const char *port = STR(DEFAULT_GIT_PORT);
struct addrinfo hints, *ai0, *ai;
int gai;
int cnt = 0;
get_host_and_port(&host, &port);
if (!*port)
port = "<none>";
memset(&hints, 0, sizeof(hints));
if (flags & CONNECT_IPV4)
hints.ai_family = AF_INET;
else if (flags & CONNECT_IPV6)
hints.ai_family = AF_INET6;
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)
/* TRANSLATORS: this is the end of "Looking up %s ... " */
fprintf(stderr, _("done.\nConnecting to %s (port %s) ... "), host, port);
for (ai0 = ai; ai; ai = ai->ai_next, cnt++) {
sockfd = socket(ai->ai_family,
ai->ai_socktype, ai->ai_protocol);
if ((sockfd < 0) ||
(connect(sockfd, ai->ai_addr, ai->ai_addrlen) < 0)) {
strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
host, cnt, ai_name(ai), strerror(errno));
if (0 <= sockfd)
close(sockfd);
sockfd = -1;
continue;
}
if (flags & CONNECT_VERBOSE)
fprintf(stderr, "%s ", ai_name(ai));
break;
}
freeaddrinfo(ai0);
if (sockfd < 0)
die(_("unable to connect to %s:\n%s"), host, error_message.buf);
enable_keepalive(sockfd);
if (flags & CONNECT_VERBOSE)
/* TRANSLATORS: this is the end of "Connecting to %s (port %s) ... " */
fprintf_ln(stderr, _("done."));
strbuf_release(&error_message);
return sockfd;
}
#else /* NO_IPV6 */
/*
* Returns a connected socket() fd, or else die()s.
*/
static int git_tcp_connect_sock(char *host, int flags)
{
struct strbuf error_message = STRBUF_INIT;
int sockfd = -1;
const char *port = STR(DEFAULT_GIT_PORT);
char *ep;
struct hostent *he;
struct sockaddr_in sa;
char **ap;
unsigned int nport;
int cnt;
get_host_and_port(&host, &port);
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"), port);
nport = se->s_port;
}
if (flags & CONNECT_VERBOSE)
/* TRANSLATORS: this is the end of "Looking up %s ... " */
fprintf(stderr, _("done.\nConnecting to %s (port %s) ... "), host, port);
for (cnt = 0, ap = he->h_addr_list; *ap; ap++, cnt++) {
memset(&sa, 0, sizeof sa);
sa.sin_family = he->h_addrtype;
sa.sin_port = htons(nport);
memcpy(&sa.sin_addr, *ap, he->h_length);
sockfd = socket(he->h_addrtype, SOCK_STREAM, 0);
if ((sockfd < 0) ||
connect(sockfd, (struct sockaddr *)&sa, sizeof sa) < 0) {
strbuf_addf(&error_message, "%s[%d: %s]: errno=%s\n",
host,
cnt,
inet_ntoa(*(struct in_addr *)&sa.sin_addr),
strerror(errno));
if (0 <= sockfd)
close(sockfd);
sockfd = -1;
continue;
}
if (flags & CONNECT_VERBOSE)
fprintf(stderr, "%s ",
inet_ntoa(*(struct in_addr *)&sa.sin_addr));
break;
}
if (sockfd < 0)
die(_("unable to connect to %s:\n%s"), host, error_message.buf);
enable_keepalive(sockfd);
if (flags & CONNECT_VERBOSE)
/* TRANSLATORS: this is the end of "Connecting to %s (port %s) ... " */
fprintf_ln(stderr, _("done."));
return sockfd;
}
#endif /* NO_IPV6 */
/*
* Dummy child_process returned by git_connect() if the transport protocol
* does not need fork(2).
*/
static struct child_process no_fork = CHILD_PROCESS_INIT;
int git_connection_is_socket(struct child_process *conn)
{
return conn == &no_fork;
}
static struct child_process *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);
return &no_fork;
}
static char *git_proxy_command;
static int git_proxy_command_options(const char *var, const char *value,
void *cb)
{
if (!strcmp(var, "core.gitproxy")) {
const char *for_pos;
int matchlen = -1;
int hostlen;
const char *rhost_name = cb;
int rhost_len = strlen(rhost_name);
if (git_proxy_command)
return 0;
if (!value)
return config_error_nonbool(var);
/* [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 = xmemdupz(value, matchlen);
}
return 0;
}
return git_default_config(var, value, cb);
}
static int git_use_proxy(const char *host)
{
git_proxy_command = getenv("GIT_PROXY_COMMAND");
git_config(git_proxy_command_options, (void*)host);
return (git_proxy_command && *git_proxy_command);
}
static struct child_process *git_proxy_connect(int fd[2], char *host)
{
const char *port = STR(DEFAULT_GIT_PORT);
struct child_process *proxy;
get_host_and_port(&host, &port);
if (looks_like_command_line_option(host))
die(_("strange hostname '%s' blocked"), host);
if (looks_like_command_line_option(port))
die(_("strange port '%s' blocked"), port);
proxy = xmalloc(sizeof(*proxy));
child_process_init(proxy);
strvec_push(&proxy->args, git_proxy_command);
strvec_push(&proxy->args, host);
strvec_push(&proxy->args, port);
proxy->in = -1;
proxy->out = -1;
if (start_command(proxy))
die(_("cannot start proxy %s"), git_proxy_command);
fd[0] = proxy->out; /* read from proxy stdout */
fd[1] = proxy->in; /* write to proxy stdin */
return proxy;
}
static char *get_port(char *host)
{
char *end;
char *p = strchr(host, ':');
if (p) {
long port = strtol(p + 1, &end, 10);
if (end != p + 1 && *end == '\0' && 0 <= port && port < 65536) {
*p = '\0';
return p+1;
}
}
return NULL;
}
/*
* Extract protocol and relevant parts from the specified connection URL.
* The caller must free() the returned strings.
*/
static enum protocol parse_connect_url(const char *url_orig, char **ret_host,
char **ret_path)
{
char *url;
char *host, *path;
char *end;
int separator = '/';
enum protocol protocol = PROTO_LOCAL;
if (is_url(url_orig))
url = url_decode(url_orig);
else
url = xstrdup(url_orig);
host = strstr(url, "://");
if (host) {
*host = '\0';
protocol = get_protocol(url);
host += 3;
} else {
host = url;
if (!url_is_local_not_ssh(url)) {
protocol = PROTO_SSH;
separator = ':';
}
}
/*
* Don't do destructive transforms as protocol code does
* '[]' unwrapping in get_host_and_port()
*/
end = host_end(&host, 0);
if (protocol == PROTO_LOCAL)
path = end;
else if (protocol == PROTO_FILE && *host != '/' &&
!has_dos_drive_prefix(host) &&
offset_1st_component(host - 2) > 1)
path = host - 2; /* include the leading "//" */
else if (protocol == PROTO_FILE && has_dos_drive_prefix(end))
path = end; /* "file://$(pwd)" may be "file://C:/projects/repo" */
else
path = strchr(end, separator);
if (!path || !*path)
die(_("no path specified; see 'git help pull' for valid url syntax"));
/*
* null-terminate hostname and point path to ~ for URL's like this:
* ssh://host.xz/~user/repo
*/
end = path; /* Need to \0 terminate host here */
if (separator == ':')
path++; /* path starts after ':' */
if (protocol == PROTO_GIT || protocol == PROTO_SSH) {
if (path[1] == '~')
path++;
}
path = xstrdup(path);
*end = '\0';
*ret_host = xstrdup(host);
*ret_path = path;
free(url);
return protocol;
}
static const char *get_ssh_command(void)
{
const char *ssh;
if ((ssh = getenv("GIT_SSH_COMMAND")))
return ssh;
if (!git_config_get_string_tmp("core.sshcommand", &ssh))
return ssh;
return NULL;
}
enum ssh_variant {
VARIANT_AUTO,
VARIANT_SIMPLE,
VARIANT_SSH,
VARIANT_PLINK,
VARIANT_PUTTY,
VARIANT_TORTOISEPLINK,
};
static void override_ssh_variant(enum ssh_variant *ssh_variant)
{
const char *variant = getenv("GIT_SSH_VARIANT");
if (!variant && git_config_get_string_tmp("ssh.variant", &variant))
return;
if (!strcmp(variant, "auto"))
*ssh_variant = VARIANT_AUTO;
else if (!strcmp(variant, "plink"))
*ssh_variant = VARIANT_PLINK;
else if (!strcmp(variant, "putty"))
*ssh_variant = VARIANT_PUTTY;
else if (!strcmp(variant, "tortoiseplink"))
*ssh_variant = VARIANT_TORTOISEPLINK;
else if (!strcmp(variant, "simple"))
*ssh_variant = VARIANT_SIMPLE;
else
*ssh_variant = VARIANT_SSH;
}
static enum ssh_variant determine_ssh_variant(const char *ssh_command,
int is_cmdline)
{
enum ssh_variant ssh_variant = VARIANT_AUTO;
const char *variant;
char *p = NULL;
override_ssh_variant(&ssh_variant);
if (ssh_variant != VARIANT_AUTO)
return ssh_variant;
if (!is_cmdline) {
p = xstrdup(ssh_command);
variant = basename(p);
} else {
const char **ssh_argv;
p = xstrdup(ssh_command);
if (split_cmdline(p, &ssh_argv) > 0) {
variant = basename((char *)ssh_argv[0]);
/*
* At this point, variant points into the buffer
* referenced by p, hence we do not need ssh_argv
* any longer.
*/
free(ssh_argv);
} else {
free(p);
return ssh_variant;
}
}
if (!strcasecmp(variant, "ssh") ||
!strcasecmp(variant, "ssh.exe"))
ssh_variant = VARIANT_SSH;
else if (!strcasecmp(variant, "plink") ||
!strcasecmp(variant, "plink.exe"))
ssh_variant = VARIANT_PLINK;
else if (!strcasecmp(variant, "tortoiseplink") ||
!strcasecmp(variant, "tortoiseplink.exe"))
ssh_variant = VARIANT_TORTOISEPLINK;
free(p);
return ssh_variant;
}
/*
* Open a connection using Git's native protocol.
*
* The caller is responsible for freeing hostandport, but this function may
* modify it (for example, to truncate it to remove the port part).
*/
static struct child_process *git_connect_git(int fd[2], char *hostandport,
const char *path, const char *prog,
enum protocol_version version,
int flags)
{
struct child_process *conn;
struct strbuf request = STRBUF_INIT;
/*
* Set up virtual host information based on where we will
* connect, unless the user has overridden us in
* the environment.
*/
char *target_host = getenv("GIT_OVERRIDE_VIRTUAL_HOST");
if (target_host)
target_host = xstrdup(target_host);
else
target_host = xstrdup(hostandport);
transport_check_allowed("git");
if (strchr(target_host, '\n') || strchr(path, '\n'))
die(_("newline is forbidden in git:// hosts and repo paths"));
/*
* These underlying connection commands die() if they
* cannot connect.
*/
if (git_use_proxy(hostandport))
conn = git_proxy_connect(fd, hostandport);
else
conn = git_tcp_connect(fd, hostandport, flags);
/*
* Separate original protocol components prog and path
* from extended host header with a NUL byte.
*
* Note: Do not add any other headers here! Doing so
* will cause older git-daemon servers to crash.
*/
strbuf_addf(&request,
"%s %s%chost=%s%c",
prog, path, 0,
target_host, 0);
/* If using a new version put that stuff here after a second null byte */
if (version > 0) {
strbuf_addch(&request, '\0');
strbuf_addf(&request, "version=%d%c",
version, '\0');
}
packet_write(fd[1], request.buf, request.len);
free(target_host);
strbuf_release(&request);
return conn;
}
/*
* Append the appropriate environment variables to `env` and options to
* `args` for running ssh in Git's SSH-tunneled transport.
*/
static void push_ssh_options(struct strvec *args, struct strvec *env,
enum ssh_variant variant, const char *port,
enum protocol_version version, int flags)
{
if (variant == VARIANT_SSH &&
version > 0) {
strvec_push(args, "-o");
strvec_push(args, "SendEnv=" GIT_PROTOCOL_ENVIRONMENT);
strvec_pushf(env, GIT_PROTOCOL_ENVIRONMENT "=version=%d",
version);
}
if (flags & CONNECT_IPV4) {
switch (variant) {
case VARIANT_AUTO:
BUG("VARIANT_AUTO passed to push_ssh_options");
case VARIANT_SIMPLE:
die(_("ssh variant 'simple' does not support -4"));
case VARIANT_SSH:
case VARIANT_PLINK:
case VARIANT_PUTTY:
case VARIANT_TORTOISEPLINK:
strvec_push(args, "-4");
}
} else if (flags & CONNECT_IPV6) {
switch (variant) {
case VARIANT_AUTO:
BUG("VARIANT_AUTO passed to push_ssh_options");
case VARIANT_SIMPLE:
die(_("ssh variant 'simple' does not support -6"));
case VARIANT_SSH:
case VARIANT_PLINK:
case VARIANT_PUTTY:
case VARIANT_TORTOISEPLINK:
strvec_push(args, "-6");
}
}
if (variant == VARIANT_TORTOISEPLINK)
strvec_push(args, "-batch");
if (port) {
switch (variant) {
case VARIANT_AUTO:
BUG("VARIANT_AUTO passed to push_ssh_options");
case VARIANT_SIMPLE:
die(_("ssh variant 'simple' does not support setting port"));
case VARIANT_SSH:
strvec_push(args, "-p");
break;
case VARIANT_PLINK:
case VARIANT_PUTTY:
case VARIANT_TORTOISEPLINK:
strvec_push(args, "-P");
}
strvec_push(args, port);
}
}
/* Prepare a child_process for use by Git's SSH-tunneled transport. */
static void fill_ssh_args(struct child_process *conn, const char *ssh_host,
const char *port, enum protocol_version version,
int flags)
{
const char *ssh;
enum ssh_variant variant;
if (looks_like_command_line_option(ssh_host))
die(_("strange hostname '%s' blocked"), ssh_host);
ssh = get_ssh_command();
if (ssh) {
variant = determine_ssh_variant(ssh, 1);
} else {
/*
* GIT_SSH is the no-shell version of
* GIT_SSH_COMMAND (and must remain so for
* historical compatibility).
*/
conn->use_shell = 0;
ssh = getenv("GIT_SSH");
if (!ssh)
ssh = "ssh";
variant = determine_ssh_variant(ssh, 0);
}
if (variant == VARIANT_AUTO) {
struct child_process detect = CHILD_PROCESS_INIT;
detect.use_shell = conn->use_shell;
detect.no_stdin = detect.no_stdout = detect.no_stderr = 1;
strvec_push(&detect.args, ssh);
strvec_push(&detect.args, "-G");
push_ssh_options(&detect.args, &detect.env_array,
VARIANT_SSH, port, version, flags);
strvec_push(&detect.args, ssh_host);
variant = run_command(&detect) ? VARIANT_SIMPLE : VARIANT_SSH;
}
strvec_push(&conn->args, ssh);
push_ssh_options(&conn->args, &conn->env_array, variant, port, version, flags);
strvec_push(&conn->args, ssh_host);
}
/*
* This returns the dummy child_process `no_fork` if the transport protocol
* does not need fork(2), or a struct child_process object 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 NULL to
* support the former case).
*
* If it returns, the connect is successful; it just dies on errors (this
* will hopefully be changed in a libification effort, to return NULL when
* the connection failed).
*/
struct child_process *git_connect(int fd[2], const char *url,
const char *prog, int flags)
{
char *hostandport, *path;
struct child_process *conn;
enum protocol protocol;
enum protocol_version version = get_protocol_version_config();
/*
* NEEDSWORK: If we are trying to use protocol v2 and we are planning
* to perform a push, then fallback to v0 since the client doesn't know
* how to push yet using v2.
*/
if (version == protocol_v2 && !strcmp("git-receive-pack", prog))
version = protocol_v0;
/* Without this we cannot rely on waitpid() to tell
* what happened to our children.
*/
signal(SIGCHLD, SIG_DFL);
protocol = parse_connect_url(url, &hostandport, &path);
if ((flags & CONNECT_DIAG_URL) && (protocol != PROTO_SSH)) {
printf("Diag: url=%s\n", url ? url : "NULL");
printf("Diag: protocol=%s\n", prot_name(protocol));
printf("Diag: hostandport=%s\n", hostandport ? hostandport : "NULL");
printf("Diag: path=%s\n", path ? path : "NULL");
conn = NULL;
} else if (protocol == PROTO_GIT) {
conn = git_connect_git(fd, hostandport, path, prog, version, flags);
conn->trace2_child_class = "transport/git";
} else {
struct strbuf cmd = STRBUF_INIT;
const char *const *var;
conn = xmalloc(sizeof(*conn));
child_process_init(conn);
if (looks_like_command_line_option(path))
die(_("strange pathname '%s' blocked"), path);
strbuf_addstr(&cmd, prog);
strbuf_addch(&cmd, ' ');
sq_quote_buf(&cmd, path);
/* remove repo-local variables from the environment */
for (var = local_repo_env; *var; var++)
strvec_push(&conn->env_array, *var);
conn->use_shell = 1;
conn->in = conn->out = -1;
if (protocol == PROTO_SSH) {
char *ssh_host = hostandport;
const char *port = NULL;
transport_check_allowed("ssh");
get_host_and_port(&ssh_host, &port);
if (!port)
port = get_port(ssh_host);
if (flags & CONNECT_DIAG_URL) {
printf("Diag: url=%s\n", url ? url : "NULL");
printf("Diag: protocol=%s\n", prot_name(protocol));
printf("Diag: userandhost=%s\n", ssh_host ? ssh_host : "NULL");
printf("Diag: port=%s\n", port ? port : "NONE");
printf("Diag: path=%s\n", path ? path : "NULL");
free(hostandport);
free(path);
free(conn);
strbuf_release(&cmd);
return NULL;
}
conn->trace2_child_class = "transport/ssh";
fill_ssh_args(conn, ssh_host, port, version, flags);
} else {
transport_check_allowed("file");
conn->trace2_child_class = "transport/file";
if (version > 0) {
strvec_pushf(&conn->env_array,
GIT_PROTOCOL_ENVIRONMENT "=version=%d",
version);
}
}
strvec_push(&conn->args, cmd.buf);
if (start_command(conn))
die(_("unable to fork"));
fd[0] = conn->out; /* read from child's stdout */
fd[1] = conn->in; /* write to child's stdin */
strbuf_release(&cmd);
}
free(hostandport);
free(path);
return conn;
}
int finish_connect(struct child_process *conn)
{
int code;
if (!conn || git_connection_is_socket(conn))
return 0;
code = finish_command(conn);
free(conn);
return code;
}