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/*
* Copyright (C) 2009-2012 the libgit2 contributors
*
* 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 <arpa/inet.h>
#else
# include <ws2tcpip.h>
# ifdef _MSC_VER
# pragma comment(lib, "ws2_32.lib")
# endif
#endif
#ifdef GIT_SSL
# include <openssl/ssl.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 "transport.h"
#ifdef GIT_WIN32
static void net_set_error(const char *str)
{
int size, error = WSAGetLastError();
LPSTR err_str = NULL;
size = FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
0, error, 0, (LPSTR)&err_str, 0, 0);
giterr_set(GITERR_NET, "%s: %s", str, err_str);
LocalFree(err_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;
err = SSL_get_error(ssl->ssl, error);
giterr_set(GITERR_NET, "SSL error: %s", ERR_error_string(err, NULL));
return -1;
}
#endif
void gitno_buffer_setup_callback(git_transport *t, gitno_buffer *buf, char *data, unsigned int len, int (*recv)(gitno_buffer *buf), void *cb_data)
{
memset(buf, 0x0, sizeof(gitno_buffer));
memset(data, 0x0, len);
buf->data = data;
buf->len = len;
buf->offset = 0;
buf->fd = t->socket;
#ifdef GIT_SSL
if (t->encrypt)
buf->ssl = &t->ssl;
#endif
buf->recv = recv;
buf->cb_data = cb_data;
}
void gitno_buffer_setup(git_transport *t, gitno_buffer *buf, char *data, unsigned int len)
{
gitno_buffer_setup_callback(t, buf, data, len, gitno__recv, NULL);
}
int gitno_recv(gitno_buffer *buf)
{
return buf->recv(buf);
}
#ifdef GIT_SSL
static int ssl_recv(gitno_ssl *ssl, void *data, size_t len)
{
int ret;
do {
ret = SSL_read(ssl->ssl, data, len);
} while (SSL_get_error(ssl->ssl, ret) == SSL_ERROR_WANT_READ);
if (ret < 0)
return ssl_set_error(ssl, ret);
return ret;
}
#endif
int gitno__recv(gitno_buffer *buf)
{
int ret;
#ifdef GIT_SSL
if (buf->ssl != NULL) {
if ((ret = ssl_recv(buf->ssl, buf->data + buf->offset, buf->len - buf->offset)) < 0)
return -1;
} else {
ret = p_recv(buf->fd, buf->data + buf->offset, buf->len - buf->offset, 0);
if (ret < 0) {
net_set_error("Error receiving socket data");
return -1;
}
}
#else
ret = p_recv(buf->fd, buf->data + buf->offset, buf->len - buf->offset, 0);
if (ret < 0) {
net_set_error("Error receiving socket data");
return -1;
}
#endif
buf->offset += ret;
return ret;
}
/* 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;
}
int gitno_ssl_teardown(git_transport *t)
{
#ifdef GIT_SSL
int ret;
#endif
if (!t->encrypt)
return 0;
#ifdef GIT_SSL
do {
ret = SSL_shutdown(t->ssl.ssl);
} while (ret == 0);
if (ret < 0)
return ssl_set_error(&t->ssl, ret);
SSL_free(t->ssl.ssl);
SSL_CTX_free(t->ssl.ctx);
#endif
return 0;
}
#ifdef GIT_SSL
/* 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(git_transport *t, 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;
/* Try to parse the host as an IP address to see if it is */
if (inet_pton(AF_INET, host, &addr4)) {
type = GEN_IPADD;
addr = &addr4;
} else {
if(inet_pton(AF_INET6, host, &addr6)) {
type = GEN_IPADD;
addr = &addr6;
}
}
cert = SSL_get_peer_certificate(t->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 on_error;
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(&t->ssl, 0);
cert_fail:
OPENSSL_free(peer_cn);
giterr_set(GITERR_SSL, "Certificate host name check failed");
return -1;
}
static int ssl_setup(git_transport *t, const char *host)
{
int ret;
SSL_library_init();
SSL_load_error_strings();
t->ssl.ctx = SSL_CTX_new(SSLv23_method());
if (t->ssl.ctx == NULL)
return ssl_set_error(&t->ssl, 0);
SSL_CTX_set_mode(t->ssl.ctx, SSL_MODE_AUTO_RETRY);
SSL_CTX_set_verify(t->ssl.ctx, SSL_VERIFY_PEER, NULL);
if (!SSL_CTX_set_default_verify_paths(t->ssl.ctx))
return ssl_set_error(&t->ssl, 0);
t->ssl.ssl = SSL_new(t->ssl.ctx);
if (t->ssl.ssl == NULL)
return ssl_set_error(&t->ssl, 0);
if((ret = SSL_set_fd(t->ssl.ssl, t->socket)) == 0)
return ssl_set_error(&t->ssl, ret);
if ((ret = SSL_connect(t->ssl.ssl)) <= 0)
return ssl_set_error(&t->ssl, ret);
if (t->check_cert && verify_server_cert(t, host) < 0)
return -1;
return 0;
}
#else
static int ssl_setup(git_transport *t, const char *host)
{
GIT_UNUSED(t);
GIT_UNUSED(host);
return 0;
}
#endif
int gitno_connect(git_transport *t, const char *host, const char *port)
{
struct addrinfo *info = NULL, *p;
struct addrinfo hints;
int ret;
GIT_SOCKET s = INVALID_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);
return -1;
}
t->socket = s;
p_freeaddrinfo(info);
if (t->encrypt && ssl_setup(t, host) < 0)
return -1;
return 0;
}
#ifdef GIT_SSL
static int send_ssl(gitno_ssl *ssl, const char *msg, size_t len)
{
int ret;
size_t off = 0;
while (off < len) {
ret = SSL_write(ssl->ssl, msg + off, len - off);
if (ret <= 0)
return ssl_set_error(ssl, ret);
off += ret;
}
return off;
}
#endif
int gitno_send(git_transport *t, const char *msg, size_t len, int flags)
{
int ret;
size_t off = 0;
#ifdef GIT_SSL
if (t->encrypt)
return send_ssl(&t->ssl, msg, len);
#endif
while (off < len) {
errno = 0;
ret = p_send(t->socket, msg + off, len - off, flags);
if (ret < 0) {
net_set_error("Error sending data");
return -1;
}
off += ret;
}
return (int)off;
}
#ifdef GIT_WIN32
int gitno_close(GIT_SOCKET s)
{
return closesocket(s) == SOCKET_ERROR ? -1 : 0;
}
#else
int gitno_close(GIT_SOCKET s)
{
return close(s);
}
#endif
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->fd, &fds);
/* The select(2) interface is silly */
return select((int)buf->fd + 1, &fds, NULL, NULL, &tv);
}
int gitno_extract_host_and_port(char **host, char **port, const char *url, const char *default_port)
{
char *colon, *slash, *delim;
colon = strchr(url, ':');
slash = strchr(url, '/');
if (slash == NULL) {
giterr_set(GITERR_NET, "Malformed URL: missing /");
return -1;
}
if (colon == NULL) {
*port = git__strdup(default_port);
} else {
*port = git__strndup(colon + 1, slash - colon - 1);
}
GITERR_CHECK_ALLOC(*port);
delim = colon == NULL ? slash : colon;
*host = git__strndup(url, delim - url);
GITERR_CHECK_ALLOC(*host);
return 0;
}
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