1 /*-------------------------------------------------------------------------
2  *
3  * libpq_be.h
4  *	  This file contains definitions for structures and externs used
5  *	  by the postmaster during client authentication.
6  *
7  *	  Note that this is backend-internal and is NOT exported to clients.
8  *	  Structs that need to be client-visible are in pqcomm.h.
9  *
10  *
11  * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
12  * Portions Copyright (c) 1994, Regents of the University of California
13  *
14  * src/include/libpq/libpq-be.h
15  *
16  *-------------------------------------------------------------------------
17  */
18 #ifndef LIBPQ_BE_H
19 #define LIBPQ_BE_H
20 
21 #ifdef HAVE_SYS_TIME_H
22 #include <sys/time.h>
23 #endif
24 #ifdef USE_OPENSSL
25 #include <openssl/ssl.h>
26 #include <openssl/err.h>
27 #endif
28 #ifdef HAVE_NETINET_TCP_H
29 #include <netinet/tcp.h>
30 #endif
31 
32 #ifdef ENABLE_GSS
33 #if defined(HAVE_GSSAPI_H)
34 #include <gssapi.h>
35 #else
36 #include <gssapi/gssapi.h>
37 #endif   /* HAVE_GSSAPI_H */
38 /*
39  * GSSAPI brings in headers that set a lot of things in the global namespace on win32,
40  * that doesn't match the msvc build. It gives a bunch of compiler warnings that we ignore,
41  * but also defines a symbol that simply does not exist. Undefine it again.
42  */
43 #ifdef WIN32_ONLY_COMPILER
44 #undef HAVE_GETADDRINFO
45 #endif
46 #endif   /* ENABLE_GSS */
47 
48 #ifdef ENABLE_SSPI
49 #define SECURITY_WIN32
50 #if defined(WIN32) && !defined(WIN32_ONLY_COMPILER)
51 #include <ntsecapi.h>
52 #endif
53 #include <security.h>
54 #undef SECURITY_WIN32
55 
56 #ifndef ENABLE_GSS
57 /*
58  * Define a fake structure compatible with GSSAPI on Unix.
59  */
60 typedef struct
61 {
62 	void	   *value;
63 	int			length;
64 } gss_buffer_desc;
65 #endif
66 #endif   /* ENABLE_SSPI */
67 
68 #include "datatype/timestamp.h"
69 #include "libpq/hba.h"
70 #include "libpq/pqcomm.h"
71 
72 
73 typedef enum CAC_state
74 {
75 	CAC_OK, CAC_STARTUP, CAC_SHUTDOWN, CAC_RECOVERY, CAC_TOOMANY,
76 	CAC_SUPERUSER
77 } CAC_state;
78 
79 
80 /*
81  * GSSAPI specific state information
82  */
83 #if defined(ENABLE_GSS) | defined(ENABLE_SSPI)
84 typedef struct
85 {
86 	gss_buffer_desc outbuf;		/* GSSAPI output token buffer */
87 #ifdef ENABLE_GSS
88 	gss_cred_id_t cred;			/* GSSAPI connection cred's */
89 	gss_ctx_id_t ctx;			/* GSSAPI connection context */
90 	gss_name_t	name;			/* GSSAPI client name */
91 #endif
92 } pg_gssinfo;
93 #endif
94 
95 /*
96  * This is used by the postmaster in its communication with frontends.  It
97  * contains all state information needed during this communication before the
98  * backend is run.  The Port structure is kept in malloc'd memory and is
99  * still available when a backend is running (see MyProcPort).  The data
100  * it points to must also be malloc'd, or else palloc'd in TopMemoryContext,
101  * so that it survives into PostgresMain execution!
102  *
103  * remote_hostname is set if we did a successful reverse lookup of the
104  * client's IP address during connection setup.
105  * remote_hostname_resolv tracks the state of hostname verification:
106  *	+1 = remote_hostname is known to resolve to client's IP address
107  *	-1 = remote_hostname is known NOT to resolve to client's IP address
108  *	 0 = we have not done the forward DNS lookup yet
109  *	-2 = there was an error in name resolution
110  * If reverse lookup of the client IP address fails, remote_hostname will be
111  * left NULL while remote_hostname_resolv is set to -2.  If reverse lookup
112  * succeeds but forward lookup fails, remote_hostname_resolv is also set to -2
113  * (the case is distinguishable because remote_hostname isn't NULL).  In
114  * either of the -2 cases, remote_hostname_errcode saves the lookup return
115  * code for possible later use with gai_strerror.
116  */
117 
118 typedef struct Port
119 {
120 	pgsocket	sock;			/* File descriptor */
121 	bool		noblock;		/* is the socket in non-blocking mode? */
122 	ProtocolVersion proto;		/* FE/BE protocol version */
123 	SockAddr	laddr;			/* local addr (postmaster) */
124 	SockAddr	raddr;			/* remote addr (client) */
125 	char	   *remote_host;	/* name (or ip addr) of remote host */
126 	char	   *remote_hostname;/* name (not ip addr) of remote host, if
127 								 * available */
128 	int			remote_hostname_resolv; /* see above */
129 	int			remote_hostname_errcode;		/* see above */
130 	char	   *remote_port;	/* text rep of remote port */
131 	CAC_state	canAcceptConnections;	/* postmaster connection status */
132 
133 	/*
134 	 * Information that needs to be saved from the startup packet and passed
135 	 * into backend execution.  "char *" fields are NULL if not set.
136 	 * guc_options points to a List of alternating option names and values.
137 	 */
138 	char	   *database_name;
139 	char	   *user_name;
140 	char	   *cmdline_options;
141 	List	   *guc_options;
142 
143 	/*
144 	 * Information that needs to be held during the authentication cycle.
145 	 */
146 	HbaLine    *hba;
147 	char		md5Salt[4];		/* Password salt */
148 
149 	/*
150 	 * Information that really has no business at all being in struct Port,
151 	 * but since it gets used by elog.c in the same way as database_name and
152 	 * other members of this struct, we may as well keep it here.
153 	 */
154 	TimestampTz SessionStartTime;		/* backend start time */
155 
156 	/*
157 	 * TCP keepalive settings.
158 	 *
159 	 * default values are 0 if AF_UNIX or not yet known; current values are 0
160 	 * if AF_UNIX or using the default. Also, -1 in a default value means we
161 	 * were unable to find out the default (getsockopt failed).
162 	 */
163 	int			default_keepalives_idle;
164 	int			default_keepalives_interval;
165 	int			default_keepalives_count;
166 	int			keepalives_idle;
167 	int			keepalives_interval;
168 	int			keepalives_count;
169 
170 #if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
171 
172 	/*
173 	 * If GSSAPI is supported, store GSSAPI information. Otherwise, store a
174 	 * NULL pointer to make sure offsets in the struct remain the same.
175 	 */
176 	pg_gssinfo *gss;
177 #else
178 	void	   *gss;
179 #endif
180 
181 	/*
182 	 * SSL structures.
183 	 */
184 	bool		ssl_in_use;
185 	char	   *peer_cn;
186 	bool		peer_cert_valid;
187 
188 	/*
189 	 * OpenSSL structures. (Keep these last so that the locations of other
190 	 * fields are the same whether or not you build with OpenSSL.)
191 	 */
192 #ifdef USE_OPENSSL
193 	SSL		   *ssl;
194 	X509	   *peer;
195 	unsigned long count;
196 #endif
197 } Port;
198 
199 #ifdef USE_SSL
200 /*
201  * These functions are implemented by the glue code specific to each
202  * SSL implementation (e.g. be-secure-openssl.c)
203  */
204 extern void be_tls_init(void);
205 extern int	be_tls_open_server(Port *port);
206 extern void be_tls_close(Port *port);
207 extern ssize_t be_tls_read(Port *port, void *ptr, size_t len, int *waitfor);
208 extern ssize_t be_tls_write(Port *port, void *ptr, size_t len, int *waitfor);
209 
210 extern int	be_tls_get_cipher_bits(Port *port);
211 extern bool be_tls_get_compression(Port *port);
212 extern void be_tls_get_version(Port *port, char *ptr, size_t len);
213 extern void be_tls_get_cipher(Port *port, char *ptr, size_t len);
214 extern void be_tls_get_peerdn_name(Port *port, char *ptr, size_t len);
215 #endif
216 
217 extern ProtocolVersion FrontendProtocol;
218 
219 /* TCP keepalives configuration. These are no-ops on an AF_UNIX socket. */
220 
221 extern int	pq_getkeepalivesidle(Port *port);
222 extern int	pq_getkeepalivesinterval(Port *port);
223 extern int	pq_getkeepalivescount(Port *port);
224 
225 extern int	pq_setkeepalivesidle(int idle, Port *port);
226 extern int	pq_setkeepalivesinterval(int interval, Port *port);
227 extern int	pq_setkeepalivescount(int count, Port *port);
228 
229 #endif   /* LIBPQ_BE_H */
230