* message integrity and endpoint authentication.
*
*
- * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.100 2007/11/15 21:14:46 momjian Exp $
+ * $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.129 2009/12/09 06:37:06 mha Exp $
*
* NOTES
- * [ Most of these notes are wrong/obsolete, but perhaps not all ]
- *
- * The client *requires* a valid server certificate. Since
- * SSH tunnels provide anonymous confidentiality, the presumption
- * is that sites that want endpoint authentication will use the
- * direct SSL support, while sites that are comfortable with
- * anonymous connections will use SSH tunnels.
- *
- * This code verifies the server certificate, to detect simple
- * "man-in-the-middle" and "impersonation" attacks. The
- * server certificate, or better yet the CA certificate used
- * to sign the server certificate, should be present in the
- * "~/.postgresql/root.crt" file. If this file isn't
- * readable, or the server certificate can't be validated,
- * pqsecure_open_client() will return an error code.
- *
- * Additionally, the server certificate's "common name" must
- * resolve to the other end of the socket. This makes it
- * substantially harder to pull off a "man-in-the-middle" or
- * "impersonation" attack even if the server's private key
- * has been stolen. This check limits acceptable network
- * layers to Unix sockets (weird, but legal), TCPv4 and TCPv6.
- *
- * Unfortunately neither the current front- or back-end handle
- * failure gracefully, resulting in the backend hiccupping.
- * This points out problems in each (the frontend shouldn't even
- * try to do SSL if pqsecure_initialize() fails, and the backend
- * shouldn't crash/recover if an SSH negotiation fails. The
- * backend definitely needs to be fixed, to prevent a "denial
- * of service" attack, but I don't know enough about how the
- * backend works (especially that pre-SSL negotiation) to identify
- * a fix.
- *
- * ...
- *
- * Unlike the server's static private key, the client's
- * static private key (~/.postgresql/postgresql.key)
- * should normally be stored encrypted. However we still
- * support EPH since it's useful for other reasons.
- *
- * ...
- *
- * Client certificates are supported, if the server requests
- * or requires them. Client certificates can be used for
- * authentication, to prevent sessions from being hijacked,
- * or to allow "road warriors" to access the database while
- * keeping it closed to everyone else.
- *
- * The user's certificate and private key are located in
- * ~/.postgresql/postgresql.crt
- * and
- * ~/.postgresql/postgresql.key
- * respectively.
- *
- * ...
*
* We don't provide informational callbacks here (like
* info_cb() in be-secure.c), since there's mechanism to
#include "libpq-fe.h"
#include "fe-auth.h"
#include "pqsignal.h"
+#include "libpq-int.h"
#ifdef WIN32
#include "win32.h"
#endif
#include <arpa/inet.h>
#endif
+
#include <sys/stat.h>
#ifdef ENABLE_THREAD_SAFETY
#endif
#ifdef USE_SSL
+
#include <openssl/ssl.h>
#include <openssl/bio.h>
#if (SSLEAY_VERSION_NUMBER >= 0x00907000L)
#include <openssl/conf.h>
#endif
-#if (SSLEAY_VERSION_NUMBER >= 0x00907000L) && !defined(OPENSSL_NO_ENGINE)
+#ifdef USE_SSL_ENGINE
#include <openssl/engine.h>
#endif
-#endif /* USE_SSL */
-
-#ifdef USE_SSL
#ifndef WIN32
#define USER_CERT_FILE ".postgresql/postgresql.crt"
#define ERR_pop_to_mark() ((void) 0)
#endif
-#ifdef NOT_USED
-static int verify_peer(PGconn *);
-#endif
+static bool verify_peer_name_matches_certificate(PGconn *);
static int verify_cb(int ok, X509_STORE_CTX *ctx);
static int client_cert_cb(SSL *, X509 **, EVP_PKEY **);
static int init_ssl_system(PGconn *conn);
+static void destroy_ssl_system(void);
static int initialize_SSL(PGconn *);
-static void destroy_SSL(void);
+static void destroySSL(void);
static PostgresPollingStatusType open_client_SSL(PGconn *);
static void close_SSL(PGconn *);
static char *SSLerrmessage(void);
static void SSLerrfree(char *buf);
-#endif
-
-#ifdef USE_SSL
-static bool pq_initssllib = true;
+static bool pq_init_ssl_lib = true;
+static bool pq_init_crypto_lib = true;
static SSL_CTX *SSL_context = NULL;
+
+#ifdef ENABLE_THREAD_SAFETY
+static long ssl_open_connections = 0;
+
+#ifndef WIN32
+static pthread_mutex_t ssl_config_mutex = PTHREAD_MUTEX_INITIALIZER;
+#else
+static pthread_mutex_t ssl_config_mutex = NULL;
+static long win32_ssl_create_mutex = 0;
#endif
+#endif /* ENABLE_THREAD_SAFETY */
+#endif /* SSL */
+
+
+/*
+ * Macros to handle disabling and then restoring the state of SIGPIPE handling.
+ * On Windows, these are all no-ops since there's no SIGPIPEs.
+ */
+
+#ifndef WIN32
+
+#define SIGPIPE_MASKED(conn) ((conn)->sigpipe_so || (conn)->sigpipe_flag)
+
+#ifdef ENABLE_THREAD_SAFETY
+
+struct sigpipe_info
+{
+ sigset_t oldsigmask;
+ bool sigpipe_pending;
+ bool got_epipe;
+};
+
+#define DECLARE_SIGPIPE_INFO(spinfo) struct sigpipe_info spinfo
+
+#define DISABLE_SIGPIPE(conn, spinfo, failaction) \
+ do { \
+ (spinfo).got_epipe = false; \
+ if (!SIGPIPE_MASKED(conn)) \
+ { \
+ if (pq_block_sigpipe(&(spinfo).oldsigmask, \
+ &(spinfo).sigpipe_pending) < 0) \
+ failaction; \
+ } \
+ } while (0)
+
+#define REMEMBER_EPIPE(spinfo, cond) \
+ do { \
+ if (cond) \
+ (spinfo).got_epipe = true; \
+ } while (0)
+
+#define RESTORE_SIGPIPE(conn, spinfo) \
+ do { \
+ if (!SIGPIPE_MASKED(conn)) \
+ pq_reset_sigpipe(&(spinfo).oldsigmask, (spinfo).sigpipe_pending, \
+ (spinfo).got_epipe); \
+ } while (0)
+
+#else /* !ENABLE_THREAD_SAFETY */
+
+#define DECLARE_SIGPIPE_INFO(spinfo) pqsigfunc spinfo = NULL
+
+#define DISABLE_SIGPIPE(conn, spinfo, failaction) \
+ do { \
+ if (!SIGPIPE_MASKED(conn)) \
+ spinfo = pqsignal(SIGPIPE, SIG_IGN); \
+ } while (0)
+
+#define REMEMBER_EPIPE(spinfo, cond)
+
+#define RESTORE_SIGPIPE(conn, spinfo) \
+ do { \
+ if (!SIGPIPE_MASKED(conn)) \
+ pqsignal(SIGPIPE, spinfo); \
+ } while (0)
+
+#endif /* ENABLE_THREAD_SAFETY */
+
+#else /* WIN32 */
+
+#define DECLARE_SIGPIPE_INFO(spinfo)
+#define DISABLE_SIGPIPE(conn, spinfo, failaction)
+#define REMEMBER_EPIPE(spinfo, cond)
+#define RESTORE_SIGPIPE(conn, spinfo)
+
+#endif /* WIN32 */
/* ------------------------------------------------------------ */
/* Procedures common to all secure sessions */
*/
void
PQinitSSL(int do_init)
+{
+ PQinitOpenSSL(do_init, do_init);
+}
+
+/*
+ * Exported function to allow application to tell us it's already
+ * initialized OpenSSL and/or libcrypto.
+ */
+void
+PQinitOpenSSL(int do_ssl, int do_crypto)
{
#ifdef USE_SSL
- pq_initssllib = do_init;
+#ifdef ENABLE_THREAD_SAFETY
+
+ /*
+ * Disallow changing the flags while we have open connections, else we'd
+ * get completely confused.
+ */
+ if (ssl_open_connections != 0)
+ return;
+#endif
+
+ pq_init_ssl_lib = do_ssl;
+ pq_init_crypto_lib = do_crypto;
#endif
}
pqsecure_destroy(void)
{
#ifdef USE_SSL
- destroy_SSL();
+ destroySSL();
#endif
}
/* First time through? */
if (conn->ssl == NULL)
{
+ /* We cannot use MSG_NOSIGNAL to block SIGPIPE when using SSL */
+ conn->sigpipe_flag = false;
+
if (!(conn->ssl = SSL_new(SSL_context)) ||
!SSL_set_app_data(conn->ssl, conn) ||
!SSL_set_fd(conn->ssl, conn->sock))
if (conn->ssl)
{
int err;
+ DECLARE_SIGPIPE_INFO(spinfo);
+
+ /* SSL_read can write to the socket, so we need to disable SIGPIPE */
+ DISABLE_SIGPIPE(conn, spinfo, return -1);
rloop:
n = SSL_read(conn->ssl, ptr, len);
char sebuf[256];
if (n == -1)
+ {
+ REMEMBER_EPIPE(spinfo, SOCK_ERRNO == EPIPE);
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("SSL SYSCALL error: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
+ }
else
{
printfPQExpBuffer(&conn->errorMessage,
n = -1;
break;
}
+
+ RESTORE_SIGPIPE(conn, spinfo);
}
else
#endif
pqsecure_write(PGconn *conn, const void *ptr, size_t len)
{
ssize_t n;
-
-#ifndef WIN32
-#ifdef ENABLE_THREAD_SAFETY
- sigset_t osigmask;
- bool sigpipe_pending;
- bool got_epipe = false;
-
-
- if (pq_block_sigpipe(&osigmask, &sigpipe_pending) < 0)
- return -1;
-#else
- pqsigfunc oldsighandler = pqsignal(SIGPIPE, SIG_IGN);
-#endif /* ENABLE_THREAD_SAFETY */
-#endif /* WIN32 */
+ DECLARE_SIGPIPE_INFO(spinfo);
#ifdef USE_SSL
if (conn->ssl)
{
int err;
+ DISABLE_SIGPIPE(conn, spinfo, return -1);
+
n = SSL_write(conn->ssl, ptr, len);
err = SSL_get_error(conn->ssl, n);
switch (err)
if (n == -1)
{
-#if defined(ENABLE_THREAD_SAFETY) && !defined(WIN32)
- if (SOCK_ERRNO == EPIPE)
- got_epipe = true;
-#endif
+ REMEMBER_EPIPE(spinfo, SOCK_ERRNO == EPIPE);
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("SSL SYSCALL error: %s\n"),
SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
else
#endif
{
- n = send(conn->sock, ptr, len, 0);
-#if defined(ENABLE_THREAD_SAFETY) && !defined(WIN32)
- if (n < 0 && SOCK_ERRNO == EPIPE)
- got_epipe = true;
-#endif
+ int flags = 0;
+
+#ifdef MSG_NOSIGNAL
+ if (conn->sigpipe_flag)
+ flags |= MSG_NOSIGNAL;
+
+retry_masked:
+
+#endif /* MSG_NOSIGNAL */
+
+ DISABLE_SIGPIPE(conn, spinfo, return -1);
+
+ n = send(conn->sock, ptr, len, flags);
+
+ if (n < 0)
+ {
+ /*
+ * If we see an EINVAL, it may be because MSG_NOSIGNAL isn't
+ * available on this machine. So, clear sigpipe_flag so we don't
+ * try the flag again, and retry the send().
+ */
+#ifdef MSG_NOSIGNAL
+ if (flags != 0 && SOCK_ERRNO == EINVAL)
+ {
+ conn->sigpipe_flag = false;
+ flags = 0;
+ goto retry_masked;
+ }
+#endif /* MSG_NOSIGNAL */
+
+ REMEMBER_EPIPE(spinfo, SOCK_ERRNO == EPIPE);
+ }
}
-#ifndef WIN32
-#ifdef ENABLE_THREAD_SAFETY
- pq_reset_sigpipe(&osigmask, sigpipe_pending, got_epipe);
-#else
- pqsignal(SIGPIPE, oldsighandler);
-#endif /* ENABLE_THREAD_SAFETY */
-#endif /* WIN32 */
+ RESTORE_SIGPIPE(conn, spinfo);
return n;
}
return ok;
}
-#ifdef NOT_USED
+
/*
- * Verify that common name resolves to peer.
+ * Check if a wildcard certificate matches the server hostname.
+ *
+ * The rule for this is:
+ * 1. We only match the '*' character as wildcard
+ * 2. We match only wildcards at the start of the string
+ * 3. The '*' character does *not* match '.', meaning that we match only
+ * a single pathname component.
+ * 4. We don't support more than one '*' in a single pattern.
+ *
+ * This is roughly in line with RFC2818, but contrary to what most browsers
+ * appear to be implementing (point 3 being the difference)
+ *
+ * Matching is always cone case-insensitive, since DNS is case insensitive.
*/
static int
-verify_peer(PGconn *conn)
+wildcard_certificate_match(const char *pattern, const char *string)
{
- struct hostent *h = NULL;
- struct sockaddr addr;
- struct sockaddr_in *sin;
- ACCEPT_TYPE_ARG3 len;
- char **s;
- unsigned long l;
-
- /* get the address on the other side of the socket */
- len = sizeof(addr);
- if (getpeername(conn->sock, &addr, &len) == -1)
- {
- char sebuf[256];
+ int lenpat = strlen(pattern);
+ int lenstr = strlen(string);
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("error querying socket: %s\n"),
- SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
- return -1;
- }
+ /* If we don't start with a wildcard, it's not a match (rule 1 & 2) */
+ if (lenpat < 3 ||
+ pattern[0] != '*' ||
+ pattern[1] != '.')
+ return 0;
- /* weird, but legal case */
- if (addr.sa_family == AF_UNIX)
+ if (lenpat > lenstr)
+ /* If pattern is longer than the string, we can never match */
return 0;
- {
- struct hostent hpstr;
- char buf[BUFSIZ];
- int herrno = 0;
+ if (pg_strcasecmp(pattern + 1, string + lenstr - lenpat + 1) != 0)
/*
- * Currently, pqGethostbyname() is used only on platforms that don't
- * have getaddrinfo(). If you enable this function, you should
- * convert the pqGethostbyname() function call to use getaddrinfo().
+ * If string does not end in pattern (minus the wildcard), we don't
+ * match
*/
- pqGethostbyname(conn->peer_cn, &hpstr, buf, sizeof(buf),
- &h, &herrno);
- }
+ return 0;
- /* what do we know about the peer's common name? */
- if (h == NULL)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("could not get information about host \"%s\": %s\n"),
- conn->peer_cn, hstrerror(h_errno));
- return -1;
- }
+ if (strchr(string, '.') < string + lenstr - lenpat)
- /* does the address match? */
- switch (addr.sa_family)
- {
- case AF_INET:
- sin = (struct sockaddr_in *) & addr;
- for (s = h->h_addr_list; *s != NULL; s++)
- {
- if (!memcmp(&sin->sin_addr.s_addr, *s, h->h_length))
- return 0;
- }
- break;
+ /*
+ * If there is a dot left of where the pattern started to match, we
+ * don't match (rule 3)
+ */
+ return 0;
+
+ /* String ended with pattern, and didn't have a dot before, so we match */
+ return 1;
+}
- default:
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("unsupported protocol\n"));
- return -1;
- }
+/*
+ * Verify that common name resolves to peer.
+ */
+static bool
+verify_peer_name_matches_certificate(PGconn *conn)
+{
/*
- * the prior test should be definitive, but in practice it sometimes
- * fails. So we also check the aliases.
+ * If told not to verify the peer name, don't do it. Return 0 indicating
+ * that the verification was successful.
*/
- for (s = h->h_aliases; *s != NULL; s++)
+ if (strcmp(conn->sslmode, "verify-full") != 0)
+ return true;
+
+ if (conn->pghostaddr)
{
- if (pg_strcasecmp(conn->peer_cn, *s) == 0)
- return 0;
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("verified SSL connections are only supported when connecting to a host name"));
+ return false;
}
-
- /* generate protocol-aware error message */
- switch (addr.sa_family)
+ else
{
- case AF_INET:
- sin = (struct sockaddr_in *) & addr;
- l = ntohl(sin->sin_addr.s_addr);
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext(
- "server common name \"%s\" does not resolve to %ld.%ld.%ld.%ld\n"),
- conn->peer_cn, (l >> 24) % 0x100, (l >> 16) % 0x100,
- (l >> 8) % 0x100, l % 0x100);
- break;
- default:
+ /*
+ * Connect by hostname.
+ *
+ * XXX: Should support alternate names here
+ */
+ if (pg_strcasecmp(conn->peer_cn, conn->pghost) == 0)
+ /* Exact name match */
+ return true;
+ else if (wildcard_certificate_match(conn->peer_cn, conn->pghost))
+ /* Matched wildcard certificate */
+ return true;
+ else
+ {
printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext(
- "server common name \"%s\" does not resolve to peer address\n"),
- conn->peer_cn);
+ libpq_gettext("server common name \"%s\" does not match host name \"%s\""),
+ conn->peer_cn, conn->pghost);
+ return false;
+ }
}
-
- return -1;
}
-#endif /* NOT_USED */
/*
* Callback used by SSL to load client cert and key.
PGconn *conn = (PGconn *) SSL_get_app_data(ssl);
char sebuf[256];
- if (!pqGetHomeDirectory(homedir, sizeof(homedir)))
+ /*
+ * If conn->sslcert or conn->sslkey is not set, we don't need the home
+ * directory to find the required files.
+ */
+ if (!conn->sslcert || !conn->sslkey)
{
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("could not get user information\n"));
- return 0;
+ if (!pqGetHomeDirectory(homedir, sizeof(homedir)))
+ {
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("could not get home directory to locate client certificate files"));
+ return 0;
+ }
}
/* read the user certificate */
- snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, USER_CERT_FILE);
+ if (conn->sslcert)
+ strncpy(fnbuf, conn->sslcert, sizeof(fnbuf));
+ else
+ snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, USER_CERT_FILE);
/*
* OpenSSL <= 0.9.8 lacks error stack handling, which means it's likely to
BIO_free(bio);
-#if (SSLEAY_VERSION_NUMBER >= 0x00907000L) && !defined(OPENSSL_NO_ENGINE)
- if (getenv("PGSSLKEY"))
+ /*
+ * Read the SSL key. If a key is specified, treat it as an engine:key
+ * combination if there is colon present - we don't support files with
+ * colon in the name. The exception is if the second character is a colon,
+ * in which case it can be a Windows filename with drive specification.
+ */
+ if (conn->sslkey && strlen(conn->sslkey) > 0)
{
- /* read the user key from engine */
- char *engine_env = getenv("PGSSLKEY");
- char *engine_colon = strchr(engine_env, ':');
- char *engine_str;
- ENGINE *engine_ptr;
-
- if (!engine_colon)
+#ifdef USE_SSL_ENGINE
+ if (strchr(conn->sslkey, ':')
+#ifdef WIN32
+ && conn->sslkey[1] != ':'
+#endif
+ )
{
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("invalid value of PGSSLKEY environment variable\n"));
- ERR_pop_to_mark();
- return 0;
- }
+ /* Colon, but not in second character, treat as engine:key */
+ char *engine_str = strdup(conn->sslkey);
+ char *engine_colon = strchr(engine_str, ':');
- engine_str = malloc(engine_colon - engine_env + 1);
- strlcpy(engine_str, engine_env, engine_colon - engine_env + 1);
- engine_ptr = ENGINE_by_id(engine_str);
- if (engine_ptr == NULL)
- {
- char *err = SSLerrmessage();
+ *engine_colon = '\0'; /* engine_str now has engine name */
+ engine_colon++; /* engine_colon now has key name */
- printfPQExpBuffer(&conn->errorMessage,
+ conn->engine = ENGINE_by_id(engine_str);
+ if (conn->engine == NULL)
+ {
+ char *err = SSLerrmessage();
+
+ printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not load SSL engine \"%s\": %s\n"),
- engine_str, err);
- SSLerrfree(err);
- free(engine_str);
- ERR_pop_to_mark();
- return 0;
- }
+ engine_str, err);
+ SSLerrfree(err);
+ free(engine_str);
+ ERR_pop_to_mark();
+ return 0;
+ }
- *pkey = ENGINE_load_private_key(engine_ptr, engine_colon + 1,
- NULL, NULL);
- if (*pkey == NULL)
- {
- char *err = SSLerrmessage();
+ if (ENGINE_init(conn->engine) == 0)
+ {
+ char *err = SSLerrmessage();
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("could not read private SSL key \"%s\" from engine \"%s\": %s\n"),
- engine_colon + 1, engine_str, err);
- SSLerrfree(err);
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("could not initialize SSL engine \"%s\": %s\n"),
+ engine_str, err);
+ SSLerrfree(err);
+ ENGINE_free(conn->engine);
+ conn->engine = NULL;
+ free(engine_str);
+ ERR_pop_to_mark();
+ return 0;
+ }
+
+ *pkey = ENGINE_load_private_key(conn->engine, engine_colon,
+ NULL, NULL);
+ if (*pkey == NULL)
+ {
+ char *err = SSLerrmessage();
+
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("could not read private SSL key \"%s\" from engine \"%s\": %s\n"),
+ engine_colon, engine_str, err);
+ SSLerrfree(err);
+ ENGINE_finish(conn->engine);
+ ENGINE_free(conn->engine);
+ conn->engine = NULL;
+ free(engine_str);
+ ERR_pop_to_mark();
+ return 0;
+ }
free(engine_str);
- ERR_pop_to_mark();
- return 0;
+
+ fnbuf[0] = '\0'; /* indicate we're not going to load from a
+ * file */
+ }
+ else
+#endif /* support for SSL engines */
+ {
+ /* PGSSLKEY is not an engine, treat it as a filename */
+ strncpy(fnbuf, conn->sslkey, sizeof(fnbuf));
}
- free(engine_str);
}
else
-#endif /* use PGSSLKEY */
{
- /* read the user key from file */
+ /* No PGSSLKEY specified, load default file */
snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, USER_KEY_FILE);
- if (stat(fnbuf, &buf) == -1)
+ }
+
+ if (fnbuf[0] != '\0')
+ {
+ /* read the user key from file */
+
+ if (stat(fnbuf, &buf) != 0)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("certificate present, but not private key file \"%s\"\n"),
return 0;
}
#ifndef WIN32
- if (!S_ISREG(buf.st_mode) || (buf.st_mode & 0077) ||
- buf.st_uid != geteuid())
+ if (!S_ISREG(buf.st_mode) || buf.st_mode & (S_IRWXG | S_IRWXO))
{
printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("private key file \"%s\" has wrong permissions\n"),
+ libpq_gettext("private key file \"%s\" has group or world access; permissions should be u=rw (0600) or less\n"),
fnbuf);
ERR_pop_to_mark();
return 0;
}
/* verify that the cert and key go together */
- if (!X509_check_private_key(*x509, *pkey))
+ if (X509_check_private_key(*x509, *pkey) != 1)
{
char *err = SSLerrmessage();
}
#ifdef ENABLE_THREAD_SAFETY
+/*
+ * Callback functions for OpenSSL internal locking
+ */
static unsigned long
pq_threadidcallback(void)
pq_lockingcallback(int mode, int n, const char *file, int line)
{
if (mode & CRYPTO_LOCK)
- pthread_mutex_lock(&pq_lockarray[n]);
+ {
+ if (pthread_mutex_lock(&pq_lockarray[n]))
+ PGTHREAD_ERROR("failed to lock mutex");
+ }
else
- pthread_mutex_unlock(&pq_lockarray[n]);
+ {
+ if (pthread_mutex_unlock(&pq_lockarray[n]))
+ PGTHREAD_ERROR("failed to unlock mutex");
+ }
}
#endif /* ENABLE_THREAD_SAFETY */
+/*
+ * Initialize SSL system. In threadsafe mode, this includes setting
+ * up libcrypto callback functions to do thread locking.
+ *
+ * If the caller has told us (through PQinitOpenSSL) that he's taking care
+ * of libcrypto, we expect that callbacks are already set, and won't try to
+ * override it.
+ *
+ * The conn parameter is only used to be able to pass back an error
+ * message - no connection local setup is made.
+ */
static int
init_ssl_system(PGconn *conn)
{
#ifdef ENABLE_THREAD_SAFETY
-#ifndef WIN32
- static pthread_mutex_t init_mutex = PTHREAD_MUTEX_INITIALIZER;
-#else
- static pthread_mutex_t init_mutex = NULL;
- static long mutex_initlock = 0;
-
- if (init_mutex == NULL)
+#ifdef WIN32
+ /* Also see similar code in fe-connect.c, default_threadlock() */
+ if (ssl_config_mutex == NULL)
{
- while (InterlockedExchange(&mutex_initlock, 1) == 1)
+ while (InterlockedExchange(&win32_ssl_create_mutex, 1) == 1)
/* loop, another thread own the lock */ ;
- if (init_mutex == NULL)
- pthread_mutex_init(&init_mutex, NULL);
- InterlockedExchange(&mutex_initlock, 0);
+ if (ssl_config_mutex == NULL)
+ {
+ if (pthread_mutex_init(&ssl_config_mutex, NULL))
+ return -1;
+ }
+ InterlockedExchange(&win32_ssl_create_mutex, 0);
}
#endif
- pthread_mutex_lock(&init_mutex);
+ if (pthread_mutex_lock(&ssl_config_mutex))
+ return -1;
- if (pq_initssllib && pq_lockarray == NULL)
+ if (pq_init_crypto_lib)
{
- int i;
+ /*
+ * If necessary, set up an array to hold locks for libcrypto.
+ * libcrypto will tell us how big to make this array.
+ */
+ if (pq_lockarray == NULL)
+ {
+ int i;
- CRYPTO_set_id_callback(pq_threadidcallback);
+ pq_lockarray = malloc(sizeof(pthread_mutex_t) * CRYPTO_num_locks());
+ if (!pq_lockarray)
+ {
+ pthread_mutex_unlock(&ssl_config_mutex);
+ return -1;
+ }
+ for (i = 0; i < CRYPTO_num_locks(); i++)
+ {
+ if (pthread_mutex_init(&pq_lockarray[i], NULL))
+ {
+ free(pq_lockarray);
+ pq_lockarray = NULL;
+ pthread_mutex_unlock(&ssl_config_mutex);
+ return -1;
+ }
+ }
+ }
- pq_lockarray = malloc(sizeof(pthread_mutex_t) * CRYPTO_num_locks());
- if (!pq_lockarray)
+ if (ssl_open_connections++ == 0)
{
- pthread_mutex_unlock(&init_mutex);
- return -1;
+ /* These are only required for threaded libcrypto applications */
+ CRYPTO_set_id_callback(pq_threadidcallback);
+ CRYPTO_set_locking_callback(pq_lockingcallback);
}
- for (i = 0; i < CRYPTO_num_locks(); i++)
- pthread_mutex_init(&pq_lockarray[i], NULL);
-
- CRYPTO_set_locking_callback(pq_lockingcallback);
}
-#endif
+#endif /* ENABLE_THREAD_SAFETY */
+
if (!SSL_context)
{
- if (pq_initssllib)
+ if (pq_init_ssl_lib)
{
#if SSLEAY_VERSION_NUMBER >= 0x00907000L
OPENSSL_config(NULL);
err);
SSLerrfree(err);
#ifdef ENABLE_THREAD_SAFETY
- pthread_mutex_unlock(&init_mutex);
+ pthread_mutex_unlock(&ssl_config_mutex);
#endif
return -1;
}
}
+
#ifdef ENABLE_THREAD_SAFETY
- pthread_mutex_unlock(&init_mutex);
+ pthread_mutex_unlock(&ssl_config_mutex);
#endif
return 0;
}
/*
- * Initialize global SSL context.
+ * This function is needed because if the libpq library is unloaded
+ * from the application, the callback functions will no longer exist when
+ * libcrypto is used by other parts of the system. For this reason,
+ * we unregister the callback functions when the last libpq
+ * connection is closed. (The same would apply for OpenSSL callbacks
+ * if we had any.)
+ *
+ * Callbacks are only set when we're compiled in threadsafe mode, so
+ * we only need to remove them in this case.
+ */
+static void
+destroy_ssl_system(void)
+{
+#ifdef ENABLE_THREAD_SAFETY
+ /* Mutex is created in initialize_ssl_system() */
+ if (pthread_mutex_lock(&ssl_config_mutex))
+ return;
+
+ if (pq_init_crypto_lib && ssl_open_connections > 0)
+ --ssl_open_connections;
+
+ if (pq_init_crypto_lib && ssl_open_connections == 0)
+ {
+ /* No connections left, unregister libcrypto callbacks */
+ CRYPTO_set_locking_callback(NULL);
+ CRYPTO_set_id_callback(NULL);
+
+ /*
+ * We don't free the lock array. If we get another connection in this
+ * process, we will just re-use it with the existing mutexes.
+ *
+ * This means we leak a little memory on repeated load/unload of the
+ * library.
+ */
+ }
+
+ pthread_mutex_unlock(&ssl_config_mutex);
+#endif
+ return;
+}
+
+/*
+ * Initialize SSL context.
*/
static int
initialize_SSL(PGconn *conn)
if (init_ssl_system(conn))
return -1;
- /* Set up to verify server cert, if root.crt is present */
- if (pqGetHomeDirectory(homedir, sizeof(homedir)))
+ /*
+ * If sslmode is set to one of the verify options, perform certificate
+ * verification. If set to "verify-full" we will also do further
+ * verification after the connection has been completed.
+ *
+ * If we are going to look for either root certificate or CRL in the home
+ * directory, we need pqGetHomeDirectory() to succeed. In other cases, we
+ * don't need to get the home directory explicitly.
+ */
+ if (!conn->sslrootcert || !conn->sslcrl)
{
- snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, ROOT_CERT_FILE);
- if (stat(fnbuf, &buf) == 0)
+ if (!pqGetHomeDirectory(homedir, sizeof(homedir)))
{
- X509_STORE *cvstore;
-
- if (!SSL_CTX_load_verify_locations(SSL_context, fnbuf, NULL))
+ if (conn->sslmode[0] == 'v') /* "verify-ca" or
+ * "verify-full" */
{
- char *err = SSLerrmessage();
-
printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("could not read root certificate file \"%s\": %s\n"),
- fnbuf, err);
- SSLerrfree(err);
+ libpq_gettext("could not get home directory to locate root certificate file"));
return -1;
}
+ }
+ }
+ else
+ {
+ homedir[0] = '\0';
+ }
- if ((cvstore = SSL_CTX_get_cert_store(SSL_context)) != NULL)
- {
- /* setting the flags to check against the complete CRL chain */
- if (X509_STORE_load_locations(cvstore, ROOT_CRL_FILE, NULL) != 0)
+ if (conn->sslrootcert)
+ strncpy(fnbuf, conn->sslrootcert, sizeof(fnbuf));
+ else
+ snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, ROOT_CERT_FILE);
+
+ if (stat(fnbuf, &buf) == 0)
+ {
+ X509_STORE *cvstore;
+
+ if (SSL_CTX_load_verify_locations(SSL_context, fnbuf, NULL) != 1)
+ {
+ char *err = SSLerrmessage();
+
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("could not read root certificate file \"%s\": %s\n"),
+ fnbuf, err);
+ SSLerrfree(err);
+ return -1;
+ }
+
+ if ((cvstore = SSL_CTX_get_cert_store(SSL_context)) != NULL)
+ {
+ if (conn->sslcrl)
+ strncpy(fnbuf, conn->sslcrl, sizeof(fnbuf));
+ else
+ snprintf(fnbuf, sizeof(fnbuf), "%s/%s", homedir, ROOT_CRL_FILE);
+
+ /* setting the flags to check against the complete CRL chain */
+ if (X509_STORE_load_locations(cvstore, fnbuf, NULL) == 1)
/* OpenSSL 0.96 does not support X509_V_FLAG_CRL_CHECK */
#ifdef X509_V_FLAG_CRL_CHECK
- X509_STORE_set_flags(cvstore,
+ X509_STORE_set_flags(cvstore,
X509_V_FLAG_CRL_CHECK | X509_V_FLAG_CRL_CHECK_ALL);
- /* if not found, silently ignore; we do not require CRL */
+ /* if not found, silently ignore; we do not require CRL */
#else
- {
- char *err = SSLerrmessage();
+ {
+ char *err = SSLerrmessage();
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("SSL library does not support CRL certificates (file \"%s\")\n"),
- fnbuf);
- SSLerrfree(err);
- return -1;
- }
-#endif
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("SSL library does not support CRL certificates (file \"%s\")\n"),
+ fnbuf);
+ SSLerrfree(err);
+ return -1;
}
+#endif
+ }
- SSL_CTX_set_verify(SSL_context, SSL_VERIFY_PEER, verify_cb);
+ SSL_CTX_set_verify(SSL_context, SSL_VERIFY_PEER, verify_cb);
+ }
+ else
+ {
+ /* stat() failed; assume cert file doesn't exist */
+ if (conn->sslmode[0] == 'v') /* "verify-ca" or "verify-full" */
+ {
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("root certificate file \"%s\" does not exist\n"
+ "Either provide the file or change sslmode to disable server certificate verification.\n"), fnbuf);
+ return -1;
}
}
return 0;
}
-/*
- * Destroy global SSL context.
- */
static void
-destroy_SSL(void)
+destroySSL(void)
{
- if (SSL_context)
- {
- SSL_CTX_free(SSL_context);
- SSL_context = NULL;
- }
+ destroy_ssl_system();
}
/*
}
}
- /* check the certificate chain of the server */
-
-#ifdef NOT_USED
- /* CLIENT CERTIFICATES NOT REQUIRED bjm 2002-09-26 */
-
/*
- * this eliminates simple man-in-the-middle attacks and simple
- * impersonations
+ * We already checked the server certificate in initialize_SSL() using
+ * SSL_CTX_set_verify() if root.crt exists.
*/
- r = SSL_get_verify_result(conn->ssl);
- if (r != X509_V_OK)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("certificate could not be validated: %s\n"),
- X509_verify_cert_error_string(r));
- close_SSL(conn);
- return PGRES_POLLING_FAILED;
- }
-#endif
/* pull out server distinguished and common names */
conn->peer = SSL_get_peer_certificate(conn->ssl);
conn->peer_dn, sizeof(conn->peer_dn));
conn->peer_dn[sizeof(conn->peer_dn) - 1] = '\0';
- X509_NAME_get_text_by_NID(X509_get_subject_name(conn->peer),
+ r = X509_NAME_get_text_by_NID(X509_get_subject_name(conn->peer),
NID_commonName, conn->peer_cn, SM_USER);
- conn->peer_cn[SM_USER] = '\0';
-
- /* verify that the common name resolves to peer */
-
-#ifdef NOT_USED
- /* CLIENT CERTIFICATES NOT REQUIRED bjm 2002-09-26 */
+ conn->peer_cn[SM_USER] = '\0'; /* buffer is SM_USER+1 chars! */
+ if (r == -1)
+ {
+ /* Unable to get the CN, set it to blank so it can't be used */
+ conn->peer_cn[0] = '\0';
+ }
+ else
+ {
+ /*
+ * Reject embedded NULLs in certificate common name to prevent attacks like
+ * CVE-2009-4034.
+ */
+ if (r != strlen(conn->peer_cn))
+ {
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("SSL certificate's common name contains embedded null\n"));
+ close_SSL(conn);
+ return PGRES_POLLING_FAILED;
+ }
+ }
- /*
- * this is necessary to eliminate man-in-the-middle attacks and
- * impersonations where the attacker somehow learned the server's private
- * key
- */
- if (verify_peer(conn) == -1)
+ if (!verify_peer_name_matches_certificate(conn))
{
close_SSL(conn);
return PGRES_POLLING_FAILED;
}
-#endif
/* SSL handshake is complete */
return PGRES_POLLING_OK;
{
if (conn->ssl)
{
+ DECLARE_SIGPIPE_INFO(spinfo);
+
+ DISABLE_SIGPIPE(conn, spinfo, (void) 0);
SSL_shutdown(conn->ssl);
SSL_free(conn->ssl);
conn->ssl = NULL;
+ pqsecure_destroy();
+ /* We have to assume we got EPIPE */
+ REMEMBER_EPIPE(spinfo, true);
+ RESTORE_SIGPIPE(conn, spinfo);
}
if (conn->peer)
X509_free(conn->peer);
conn->peer = NULL;
}
+
+#ifdef USE_SSL_ENGINE
+ if (conn->engine)
+ {
+ ENGINE_finish(conn->engine);
+ ENGINE_free(conn->engine);
+ conn->engine = NULL;
+ }
+#endif
}
/*
}
#endif /* USE_SSL */
+
#if defined(ENABLE_THREAD_SAFETY) && !defined(WIN32)
/*
SOCK_ERRNO_SET(save_errno);
}
-#endif /* ENABLE_THREAD_SAFETY */
+#endif /* ENABLE_THREAD_SAFETY && !WIN32 */
projects / postgresql / blobdiff