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Diffstat (limited to 'src/include/libpq/pqcomm.h')
| -rw-r--r-- | src/include/libpq/pqcomm.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/include/libpq/pqcomm.h b/src/include/libpq/pqcomm.h new file mode 100644 index 0000000..b418283 --- /dev/null +++ b/src/include/libpq/pqcomm.h @@ -0,0 +1,194 @@ +/*------------------------------------------------------------------------- + * + * pqcomm.h + * Definitions common to frontends and backends. + * + * NOTE: for historical reasons, this does not correspond to pqcomm.c. + * pqcomm.c's routines are declared in libpq.h. + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/libpq/pqcomm.h + * + *------------------------------------------------------------------------- + */ +#ifndef PQCOMM_H +#define PQCOMM_H + +#include <sys/socket.h> +#include <netdb.h> +#ifdef HAVE_SYS_UN_H +#include <sys/un.h> +#endif +#include <netinet/in.h> + +#ifdef HAVE_STRUCT_SOCKADDR_STORAGE + +#ifndef HAVE_STRUCT_SOCKADDR_STORAGE_SS_FAMILY +#ifdef HAVE_STRUCT_SOCKADDR_STORAGE___SS_FAMILY +#define ss_family __ss_family +#else +#error struct sockaddr_storage does not provide an ss_family member +#endif +#endif + +#ifdef HAVE_STRUCT_SOCKADDR_STORAGE___SS_LEN +#define ss_len __ss_len +#define HAVE_STRUCT_SOCKADDR_STORAGE_SS_LEN 1 +#endif +#else /* !HAVE_STRUCT_SOCKADDR_STORAGE */ + +/* Define a struct sockaddr_storage if we don't have one. */ + +struct sockaddr_storage +{ + union + { + struct sockaddr sa; /* get the system-dependent fields */ + int64 ss_align; /* ensures struct is properly aligned */ + char ss_pad[128]; /* ensures struct has desired size */ + } ss_stuff; +}; + +#define ss_family ss_stuff.sa.sa_family +/* It should have an ss_len field if sockaddr has sa_len. */ +#ifdef HAVE_STRUCT_SOCKADDR_SA_LEN +#define ss_len ss_stuff.sa.sa_len +#define HAVE_STRUCT_SOCKADDR_STORAGE_SS_LEN 1 +#endif +#endif /* HAVE_STRUCT_SOCKADDR_STORAGE */ + +typedef struct +{ + struct sockaddr_storage addr; + socklen_t salen; +} SockAddr; + +/* Configure the UNIX socket location for the well known port. */ + +#define UNIXSOCK_PATH(path, port, sockdir) \ + (AssertMacro(sockdir), \ + AssertMacro(*(sockdir) != '\0'), \ + snprintf(path, sizeof(path), "%s/.s.PGSQL.%d", \ + (sockdir), (port))) + +/* + * The maximum workable length of a socket path is what will fit into + * struct sockaddr_un. This is usually only 100 or so bytes :-(. + * + * For consistency, always pass a MAXPGPATH-sized buffer to UNIXSOCK_PATH(), + * then complain if the resulting string is >= UNIXSOCK_PATH_BUFLEN bytes. + * (Because the standard API for getaddrinfo doesn't allow it to complain in + * a useful way when the socket pathname is too long, we have to test for + * this explicitly, instead of just letting the subroutine return an error.) + */ +#define UNIXSOCK_PATH_BUFLEN sizeof(((struct sockaddr_un *) NULL)->sun_path) + +/* + * A host that looks either like an absolute path or starts with @ is + * interpreted as a Unix-domain socket address. + */ +static inline bool +is_unixsock_path(const char *path) +{ + return is_absolute_path(path) || path[0] == '@'; +} + +/* + * These manipulate the frontend/backend protocol version number. + * + * The major number should be incremented for incompatible changes. The minor + * number should be incremented for compatible changes (eg. additional + * functionality). + * + * If a backend supports version m.n of the protocol it must actually support + * versions m.[0..n]. Backend support for version m-1 can be dropped after a + * `reasonable' length of time. + * + * A frontend isn't required to support anything other than the current + * version. + */ + +#define PG_PROTOCOL_MAJOR(v) ((v) >> 16) +#define PG_PROTOCOL_MINOR(v) ((v) & 0x0000ffff) +#define PG_PROTOCOL(m,n) (((m) << 16) | (n)) + +/* + * The earliest and latest frontend/backend protocol version supported. + * (Only protocol version 3 is currently supported) + */ + +#define PG_PROTOCOL_EARLIEST PG_PROTOCOL(3,0) +#define PG_PROTOCOL_LATEST PG_PROTOCOL(3,0) + +typedef uint32 ProtocolVersion; /* FE/BE protocol version number */ + +typedef ProtocolVersion MsgType; + + +/* + * Packet lengths are 4 bytes in network byte order. + * + * The initial length is omitted from the packet layouts appearing below. + */ + +typedef uint32 PacketLen; + +extern PGDLLIMPORT bool Db_user_namespace; + +/* + * In protocol 3.0 and later, the startup packet length is not fixed, but + * we set an arbitrary limit on it anyway. This is just to prevent simple + * denial-of-service attacks via sending enough data to run the server + * out of memory. + */ +#define MAX_STARTUP_PACKET_LENGTH 10000 + + +/* These are the authentication request codes sent by the backend. */ + +#define AUTH_REQ_OK 0 /* User is authenticated */ +#define AUTH_REQ_KRB4 1 /* Kerberos V4. Not supported any more. */ +#define AUTH_REQ_KRB5 2 /* Kerberos V5. Not supported any more. */ +#define AUTH_REQ_PASSWORD 3 /* Password */ +#define AUTH_REQ_CRYPT 4 /* crypt password. Not supported any more. */ +#define AUTH_REQ_MD5 5 /* md5 password */ +#define AUTH_REQ_SCM_CREDS 6 /* transfer SCM credentials */ +#define AUTH_REQ_GSS 7 /* GSSAPI without wrap() */ +#define AUTH_REQ_GSS_CONT 8 /* Continue GSS exchanges */ +#define AUTH_REQ_SSPI 9 /* SSPI negotiate without wrap() */ +#define AUTH_REQ_SASL 10 /* Begin SASL authentication */ +#define AUTH_REQ_SASL_CONT 11 /* Continue SASL authentication */ +#define AUTH_REQ_SASL_FIN 12 /* Final SASL message */ + +typedef uint32 AuthRequest; + + +/* + * A client can also send a cancel-current-operation request to the postmaster. + * This is uglier than sending it directly to the client's backend, but it + * avoids depending on out-of-band communication facilities. + * + * The cancel request code must not match any protocol version number + * we're ever likely to use. This random choice should do. + */ +#define CANCEL_REQUEST_CODE PG_PROTOCOL(1234,5678) + +typedef struct CancelRequestPacket +{ + /* Note that each field is stored in network byte order! */ + MsgType cancelRequestCode; /* code to identify a cancel request */ + uint32 backendPID; /* PID of client's backend */ + uint32 cancelAuthCode; /* secret key to authorize cancel */ +} CancelRequestPacket; + + +/* + * A client can also start by sending a SSL or GSSAPI negotiation request to + * get a secure channel. + */ +#define NEGOTIATE_SSL_CODE PG_PROTOCOL(1234,5679) +#define NEGOTIATE_GSS_CODE PG_PROTOCOL(1234,5680) + +#endif /* PQCOMM_H */ |