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|
/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#ifndef _WIN32
# include <sys/types.h>
# include <sys/socket.h>
# include <sys/select.h>
# include <sys/time.h>
# include <netdb.h>
# include <netinet/in.h>
# include <arpa/inet.h>
#else
# include <ws2tcpip.h>
# ifdef _MSC_VER
# pragma comment(lib, "ws2_32")
# endif
#endif
#ifdef GIT_SSL
# include <openssl/ssl.h>
# include <openssl/err.h>
# include <openssl/x509v3.h>
#endif
#include <ctype.h>
#include "git2/errors.h"
#include "common.h"
#include "netops.h"
#include "posix.h"
#include "buffer.h"
#include "http_parser.h"
#ifdef GIT_WIN32
static void net_set_error(const char *str)
{
int error = WSAGetLastError();
char * win32_error = git_win32_get_error_message(error);
if (win32_error) {
giterr_set(GITERR_NET, "%s: %s", str, win32_error);
git__free(win32_error);
} else {
giterr_set(GITERR_NET, str);
}
}
#else
static void net_set_error(const char *str)
{
giterr_set(GITERR_NET, "%s: %s", str, strerror(errno));
}
#endif
#ifdef GIT_SSL
static int ssl_set_error(gitno_ssl *ssl, int error)
{
int err;
unsigned long e;
err = SSL_get_error(ssl->ssl, error);
assert(err != SSL_ERROR_WANT_READ);
assert(err != SSL_ERROR_WANT_WRITE);
switch (err) {
case SSL_ERROR_WANT_CONNECT:
case SSL_ERROR_WANT_ACCEPT:
giterr_set(GITERR_NET, "SSL error: connection failure\n");
break;
case SSL_ERROR_WANT_X509_LOOKUP:
giterr_set(GITERR_NET, "SSL error: x509 error\n");
break;
case SSL_ERROR_SYSCALL:
e = ERR_get_error();
if (e > 0) {
giterr_set(GITERR_NET, "SSL error: %s",
ERR_error_string(e, NULL));
break;
} else if (error < 0) {
giterr_set(GITERR_OS, "SSL error: syscall failure");
break;
}
giterr_set(GITERR_NET, "SSL error: received early EOF");
break;
case SSL_ERROR_SSL:
e = ERR_get_error();
giterr_set(GITERR_NET, "SSL error: %s",
ERR_error_string(e, NULL));
break;
case SSL_ERROR_NONE:
case SSL_ERROR_ZERO_RETURN:
default:
giterr_set(GITERR_NET, "SSL error: unknown error");
break;
}
return -1;
}
#endif
int gitno_recv(gitno_buffer *buf)
{
return buf->recv(buf);
}
#ifdef GIT_SSL
static int gitno__recv_ssl(gitno_buffer *buf)
{
int ret;
do {
ret = SSL_read(buf->socket->ssl.ssl, buf->data + buf->offset, buf->len - buf->offset);
} while (SSL_get_error(buf->socket->ssl.ssl, ret) == SSL_ERROR_WANT_READ);
if (ret < 0) {
net_set_error("Error receiving socket data");
return -1;
}
buf->offset += ret;
return ret;
}
#endif
static int gitno__recv(gitno_buffer *buf)
{
int ret;
ret = p_recv(buf->socket->socket, buf->data + buf->offset, buf->len - buf->offset, 0);
if (ret < 0) {
net_set_error("Error receiving socket data");
return -1;
}
buf->offset += ret;
return ret;
}
void gitno_buffer_setup_callback(
gitno_socket *socket,
gitno_buffer *buf,
char *data,
size_t len,
int (*recv)(gitno_buffer *buf), void *cb_data)
{
memset(data, 0x0, len);
buf->data = data;
buf->len = len;
buf->offset = 0;
buf->socket = socket;
buf->recv = recv;
buf->cb_data = cb_data;
}
void gitno_buffer_setup(gitno_socket *socket, gitno_buffer *buf, char *data, size_t len)
{
#ifdef GIT_SSL
if (socket->ssl.ctx) {
gitno_buffer_setup_callback(socket, buf, data, len, gitno__recv_ssl, NULL);
return;
}
#endif
gitno_buffer_setup_callback(socket, buf, data, len, gitno__recv, NULL);
}
/* Consume up to ptr and move the rest of the buffer to the beginning */
void gitno_consume(gitno_buffer *buf, const char *ptr)
{
size_t consumed;
assert(ptr - buf->data >= 0);
assert(ptr - buf->data <= (int) buf->len);
consumed = ptr - buf->data;
memmove(buf->data, ptr, buf->offset - consumed);
memset(buf->data + buf->offset, 0x0, buf->len - buf->offset);
buf->offset -= consumed;
}
/* Consume const bytes and move the rest of the buffer to the beginning */
void gitno_consume_n(gitno_buffer *buf, size_t cons)
{
memmove(buf->data, buf->data + cons, buf->len - buf->offset);
memset(buf->data + cons, 0x0, buf->len - buf->offset);
buf->offset -= cons;
}
#ifdef GIT_SSL
static int gitno_ssl_teardown(gitno_ssl *ssl)
{
int ret;
ret = SSL_shutdown(ssl->ssl);
if (ret < 0)
ret = ssl_set_error(ssl, ret);
else
ret = 0;
SSL_free(ssl->ssl);
SSL_CTX_free(ssl->ctx);
return ret;
}
/* Match host names according to RFC 2818 rules */
static int match_host(const char *pattern, const char *host)
{
for (;;) {
char c = tolower(*pattern++);
if (c == '\0')
return *host ? -1 : 0;
if (c == '*') {
c = *pattern;
/* '*' at the end matches everything left */
if (c == '\0')
return 0;
/*
* We've found a pattern, so move towards the next matching
* char. The '.' is handled specially because wildcards aren't
* allowed to cross subdomains.
*/
while(*host) {
char h = tolower(*host);
if (c == h)
return match_host(pattern, host++);
if (h == '.')
return match_host(pattern, host);
host++;
}
return -1;
}
if (c != tolower(*host++))
return -1;
}
return -1;
}
static int check_host_name(const char *name, const char *host)
{
if (!strcasecmp(name, host))
return 0;
if (match_host(name, host) < 0)
return -1;
return 0;
}
static int verify_server_cert(gitno_ssl *ssl, const char *host)
{
X509 *cert;
X509_NAME *peer_name;
ASN1_STRING *str;
unsigned char *peer_cn = NULL;
int matched = -1, type = GEN_DNS;
GENERAL_NAMES *alts;
struct in6_addr addr6;
struct in_addr addr4;
void *addr;
int i = -1,j;
if (SSL_get_verify_result(ssl->ssl) != X509_V_OK) {
giterr_set(GITERR_SSL, "The SSL certificate is invalid");
return -1;
}
/* Try to parse the host as an IP address to see if it is */
if (p_inet_pton(AF_INET, host, &addr4)) {
type = GEN_IPADD;
addr = &addr4;
} else {
if(p_inet_pton(AF_INET6, host, &addr6)) {
type = GEN_IPADD;
addr = &addr6;
}
}
cert = SSL_get_peer_certificate(ssl->ssl);
/* Check the alternative names */
alts = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
if (alts) {
int num;
num = sk_GENERAL_NAME_num(alts);
for (i = 0; i < num && matched != 1; i++) {
const GENERAL_NAME *gn = sk_GENERAL_NAME_value(alts, i);
const char *name = (char *) ASN1_STRING_data(gn->d.ia5);
size_t namelen = (size_t) ASN1_STRING_length(gn->d.ia5);
/* Skip any names of a type we're not looking for */
if (gn->type != type)
continue;
if (type == GEN_DNS) {
/* If it contains embedded NULs, don't even try */
if (memchr(name, '\0', namelen))
continue;
if (check_host_name(name, host) < 0)
matched = 0;
else
matched = 1;
} else if (type == GEN_IPADD) {
/* Here name isn't so much a name but a binary representation of the IP */
matched = !!memcmp(name, addr, namelen);
}
}
}
GENERAL_NAMES_free(alts);
if (matched == 0)
goto cert_fail;
if (matched == 1)
return 0;
/* If no alternative names are available, check the common name */
peer_name = X509_get_subject_name(cert);
if (peer_name == NULL)
goto on_error;
if (peer_name) {
/* Get the index of the last CN entry */
while ((j = X509_NAME_get_index_by_NID(peer_name, NID_commonName, i)) >= 0)
i = j;
}
if (i < 0)
goto on_error;
str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(peer_name, i));
if (str == NULL)
goto on_error;
/* Work around a bug in OpenSSL whereby ASN1_STRING_to_UTF8 fails if it's already in utf-8 */
if (ASN1_STRING_type(str) == V_ASN1_UTF8STRING) {
int size = ASN1_STRING_length(str);
if (size > 0) {
peer_cn = OPENSSL_malloc(size + 1);
GITERR_CHECK_ALLOC(peer_cn);
memcpy(peer_cn, ASN1_STRING_data(str), size);
peer_cn[size] = '\0';
}
} else {
int size = ASN1_STRING_to_UTF8(&peer_cn, str);
GITERR_CHECK_ALLOC(peer_cn);
if (memchr(peer_cn, '\0', size))
goto cert_fail;
}
if (check_host_name((char *)peer_cn, host) < 0)
goto cert_fail;
OPENSSL_free(peer_cn);
return 0;
on_error:
OPENSSL_free(peer_cn);
return ssl_set_error(ssl, 0);
cert_fail:
OPENSSL_free(peer_cn);
giterr_set(GITERR_SSL, "Certificate host name check failed");
return -1;
}
static int ssl_setup(gitno_socket *socket, const char *host, int flags)
{
int ret;
SSL_library_init();
SSL_load_error_strings();
socket->ssl.ctx = SSL_CTX_new(SSLv23_method());
if (socket->ssl.ctx == NULL)
return ssl_set_error(&socket->ssl, 0);
SSL_CTX_set_mode(socket->ssl.ctx, SSL_MODE_AUTO_RETRY);
SSL_CTX_set_verify(socket->ssl.ctx, SSL_VERIFY_NONE, NULL);
if (!SSL_CTX_set_default_verify_paths(socket->ssl.ctx))
return ssl_set_error(&socket->ssl, 0);
socket->ssl.ssl = SSL_new(socket->ssl.ctx);
if (socket->ssl.ssl == NULL)
return ssl_set_error(&socket->ssl, 0);
if((ret = SSL_set_fd(socket->ssl.ssl, socket->socket)) == 0)
return ssl_set_error(&socket->ssl, ret);
if ((ret = SSL_connect(socket->ssl.ssl)) <= 0)
return ssl_set_error(&socket->ssl, ret);
if (GITNO_CONNECT_SSL_NO_CHECK_CERT & flags)
return 0;
return verify_server_cert(&socket->ssl, host);
}
#endif
static int gitno__close(GIT_SOCKET s)
{
#ifdef GIT_WIN32
if (SOCKET_ERROR == closesocket(s))
return -1;
if (0 != WSACleanup()) {
giterr_set(GITERR_OS, "Winsock cleanup failed");
return -1;
}
return 0;
#else
return close(s);
#endif
}
int gitno_connect(gitno_socket *s_out, const char *host, const char *port, int flags)
{
struct addrinfo *info = NULL, *p;
struct addrinfo hints;
GIT_SOCKET s = INVALID_SOCKET;
int ret;
#ifdef GIT_WIN32
/* on win32, the WSA context needs to be initialized
* before any socket calls can be performed */
WSADATA wsd;
if (WSAStartup(MAKEWORD(2,2), &wsd) != 0) {
giterr_set(GITERR_OS, "Winsock init failed");
return -1;
}
if (LOBYTE(wsd.wVersion) != 2 || HIBYTE(wsd.wVersion) != 2) {
WSACleanup();
giterr_set(GITERR_OS, "Winsock init failed");
return -1;
}
#endif
/* Zero the socket structure provided */
memset(s_out, 0x0, sizeof(gitno_socket));
memset(&hints, 0x0, sizeof(struct addrinfo));
hints.ai_socktype = SOCK_STREAM;
hints.ai_family = AF_UNSPEC;
if ((ret = p_getaddrinfo(host, port, &hints, &info)) < 0) {
giterr_set(GITERR_NET,
"Failed to resolve address for %s: %s", host, p_gai_strerror(ret));
return -1;
}
for (p = info; p != NULL; p = p->ai_next) {
s = socket(p->ai_family, p->ai_socktype, p->ai_protocol);
if (s == INVALID_SOCKET) {
net_set_error("error creating socket");
break;
}
if (connect(s, p->ai_addr, (socklen_t)p->ai_addrlen) == 0)
break;
/* If we can't connect, try the next one */
gitno__close(s);
s = INVALID_SOCKET;
}
/* Oops, we couldn't connect to any address */
if (s == INVALID_SOCKET && p == NULL) {
giterr_set(GITERR_OS, "Failed to connect to %s", host);
p_freeaddrinfo(info);
return -1;
}
s_out->socket = s;
p_freeaddrinfo(info);
#ifdef GIT_SSL
if ((flags & GITNO_CONNECT_SSL) && ssl_setup(s_out, host, flags) < 0)
return -1;
#else
/* SSL is not supported */
if (flags & GITNO_CONNECT_SSL) {
giterr_set(GITERR_OS, "SSL is not supported by this copy of libgit2.");
return -1;
}
#endif
return 0;
}
#ifdef GIT_SSL
static int gitno_send_ssl(gitno_ssl *ssl, const char *msg, size_t len, int flags)
{
int ret;
size_t off = 0;
GIT_UNUSED(flags);
while (off < len) {
ret = SSL_write(ssl->ssl, msg + off, len - off);
if (ret <= 0 && ret != SSL_ERROR_WANT_WRITE)
return ssl_set_error(ssl, ret);
off += ret;
}
return off;
}
#endif
int gitno_send(gitno_socket *socket, const char *msg, size_t len, int flags)
{
int ret;
size_t off = 0;
#ifdef GIT_SSL
if (socket->ssl.ctx)
return gitno_send_ssl(&socket->ssl, msg, len, flags);
#endif
while (off < len) {
errno = 0;
ret = p_send(socket->socket, msg + off, len - off, flags);
if (ret < 0) {
net_set_error("Error sending data");
return -1;
}
off += ret;
}
return (int)off;
}
int gitno_close(gitno_socket *s)
{
#ifdef GIT_SSL
if (s->ssl.ctx &&
gitno_ssl_teardown(&s->ssl) < 0)
return -1;
#endif
return gitno__close(s->socket);
}
int gitno_select_in(gitno_buffer *buf, long int sec, long int usec)
{
fd_set fds;
struct timeval tv;
tv.tv_sec = sec;
tv.tv_usec = usec;
FD_ZERO(&fds);
FD_SET(buf->socket->socket, &fds);
/* The select(2) interface is silly */
return select((int)buf->socket->socket + 1, &fds, NULL, NULL, &tv);
}
static const char *prefix_http = "http://";
static const char *prefix_https = "https://";
int gitno_connection_data_from_url(
gitno_connection_data *data,
const char *url,
const char *service_suffix)
{
int error = -1;
const char *default_port = NULL, *path_search_start = NULL;
char *original_host = NULL;
/* service_suffix is optional */
assert(data && url);
/* Save these for comparison later */
original_host = data->host;
data->host = NULL;
gitno_connection_data_free_ptrs(data);
if (!git__prefixcmp(url, prefix_http)) {
path_search_start = url + strlen(prefix_http);
default_port = "80";
if (data->use_ssl) {
giterr_set(GITERR_NET, "Redirect from HTTPS to HTTP is not allowed");
goto cleanup;
}
} else if (!git__prefixcmp(url, prefix_https)) {
path_search_start = url + strlen(prefix_https);
default_port = "443";
data->use_ssl = true;
} else if (url[0] == '/')
default_port = data->use_ssl ? "443" : "80";
if (!default_port) {
giterr_set(GITERR_NET, "Unrecognized URL prefix");
goto cleanup;
}
error = gitno_extract_url_parts(
&data->host, &data->port, &data->path, &data->user, &data->pass,
url, default_port);
if (url[0] == '/') {
/* Relative redirect; reuse original host name and port */
path_search_start = url;
git__free(data->host);
data->host = original_host;
original_host = NULL;
}
if (!error) {
const char *path = strchr(path_search_start, '/');
size_t pathlen = strlen(path);
size_t suffixlen = service_suffix ? strlen(service_suffix) : 0;
if (suffixlen &&
!memcmp(path + pathlen - suffixlen, service_suffix, suffixlen))
data->path = git__strndup(path, pathlen - suffixlen);
else
data->path = git__strdup(path);
/* Check for errors in the resulting data */
if (original_host && url[0] != '/' && strcmp(original_host, data->host)) {
giterr_set(GITERR_NET, "Cross host redirect not allowed");
error = -1;
}
}
cleanup:
if (original_host) git__free(original_host);
return error;
}
void gitno_connection_data_free_ptrs(gitno_connection_data *d)
{
git__free(d->host); d->host = NULL;
git__free(d->port); d->port = NULL;
git__free(d->path); d->path = NULL;
git__free(d->user); d->user = NULL;
git__free(d->pass); d->pass = NULL;
}
#define hex2c(c) ((c | 32) % 39 - 9)
static char* unescape(char *str)
{
int x, y;
size_t len = strlen(str);
for (x=y=0; str[y]; ++x, ++y) {
if ((str[x] = str[y]) == '%') {
if (y < len-2 && isxdigit(str[y+1]) && isxdigit(str[y+2])) {
str[x] = (hex2c(str[y+1]) << 4) + hex2c(str[y+2]);
y += 2;
}
}
}
str[x] = '\0';
return str;
}
int gitno_extract_url_parts(
char **host,
char **port,
char **path,
char **username,
char **password,
const char *url,
const char *default_port)
{
struct http_parser_url u = {0};
const char *_host, *_port, *_path, *_userinfo;
if (http_parser_parse_url(url, strlen(url), false, &u)) {
giterr_set(GITERR_NET, "Malformed URL '%s'", url);
return GIT_EINVALIDSPEC;
}
_host = url+u.field_data[UF_HOST].off;
_port = url+u.field_data[UF_PORT].off;
_path = url+u.field_data[UF_PATH].off;
_userinfo = url+u.field_data[UF_USERINFO].off;
if (u.field_set & (1 << UF_HOST)) {
*host = git__substrdup(_host, u.field_data[UF_HOST].len);
GITERR_CHECK_ALLOC(*host);
}
if (u.field_set & (1 << UF_PORT))
*port = git__substrdup(_port, u.field_data[UF_PORT].len);
else
*port = git__strdup(default_port);
GITERR_CHECK_ALLOC(*port);
if (u.field_set & (1 << UF_PATH)) {
*path = git__substrdup(_path, u.field_data[UF_PATH].len);
GITERR_CHECK_ALLOC(*path);
}
if (u.field_set & (1 << UF_USERINFO)) {
const char *colon = memchr(_userinfo, ':', u.field_data[UF_USERINFO].len);
if (colon) {
*username = unescape(git__substrdup(_userinfo, colon - _userinfo));
*password = unescape(git__substrdup(colon+1, u.field_data[UF_USERINFO].len - (colon+1-_userinfo)));
GITERR_CHECK_ALLOC(*password);
} else {
*username = git__substrdup(_userinfo, u.field_data[UF_USERINFO].len);
}
GITERR_CHECK_ALLOC(*username);
}
return 0;
}
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