[2.7] bpo-32185: Don't send IP in SNI TLS extension (GH-5865) (#5871)

The SSL module no longer sends IP addresses in SNI TLS extension on
platforms with OpenSSL 1.0.2+ or inet_pton.

Signed-off-by: Christian Heimes <christian@python.org>
(cherry picked from commit e9370a4738)

Co-authored-by: Christian Heimes <christian@python.org>
This commit is contained in:
Miss Islington (bot) 2018-02-25 01:16:37 -08:00 committed by Christian Heimes
parent 6e8f395001
commit a5c9112300
2 changed files with 42 additions and 2 deletions

View File

@ -0,0 +1,2 @@
The SSL module no longer sends IP addresses in SNI TLS extension on
platforms with OpenSSL 1.0.2+ or inet_pton.

View File

@ -52,6 +52,11 @@
#include <sys/poll.h>
#endif
#ifndef MS_WINDOWS
/* inet_pton */
#include <arpa/inet.h>
#endif
/* Don't warn about deprecated functions */
#ifdef __GNUC__
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
@ -575,8 +580,41 @@ newPySSLSocket(PySSLContext *sslctx, PySocketSockObject *sock,
SSL_set_mode(self->ssl, mode);
#if HAVE_SNI
if (server_hostname != NULL)
if (server_hostname != NULL) {
/* Don't send SNI for IP addresses. We cannot simply use inet_aton() and
* inet_pton() here. inet_aton() may be linked weakly and inet_pton() isn't
* available on all platforms. Use OpenSSL's IP address parser. It's
* available since 1.0.2 and LibreSSL since at least 2.3.0. */
int send_sni = 1;
#if OPENSSL_VERSION_NUMBER >= 0x10200000L
ASN1_OCTET_STRING *ip = a2i_IPADDRESS(server_hostname);
if (ip == NULL) {
send_sni = 1;
ERR_clear_error();
} else {
send_sni = 0;
ASN1_OCTET_STRING_free(ip);
}
#elif defined(HAVE_INET_PTON)
#ifdef ENABLE_IPV6
char packed[Py_MAX(sizeof(struct in_addr), sizeof(struct in6_addr))];
#else
char packed[sizeof(struct in_addr)];
#endif /* ENABLE_IPV6 */
if (inet_pton(AF_INET, server_hostname, packed)) {
send_sni = 0;
#ifdef ENABLE_IPV6
} else if(inet_pton(AF_INET6, server_hostname, packed)) {
send_sni = 0;
#endif /* ENABLE_IPV6 */
} else {
send_sni = 1;
}
#endif /* HAVE_INET_PTON */
if (send_sni) {
SSL_set_tlsext_host_name(self->ssl, server_hostname);
}
}
#endif
/* If the socket is in non-blocking mode or timeout mode, set the BIO