Adding upstream version 14.5.upstream/14.5upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3166 insertions, 0 deletions

diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
new file mode 100644
index 0000000..64e59d4
--- /dev/null
+++ b/src/backend/libpq/hba.c
@@ -0,0 +1,3166 @@
+/*-------------------------------------------------------------------------
+ *
+ * hba.c
+ *	  Routines to handle host based authentication (that's the scheme
+ *	  wherein you authenticate a user by seeing what IP address the system
+ *	  says he comes from and choosing authentication method based on it).
+ *
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/libpq/hba.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include <ctype.h>
+#include <pwd.h>
+#include <fcntl.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+
+#include "access/htup_details.h"
+#include "catalog/pg_collation.h"
+#include "catalog/pg_type.h"
+#include "common/ip.h"
+#include "common/string.h"
+#include "funcapi.h"
+#include "libpq/ifaddr.h"
+#include "libpq/libpq.h"
+#include "miscadmin.h"
+#include "postmaster/postmaster.h"
+#include "regex/regex.h"
+#include "replication/walsender.h"
+#include "storage/fd.h"
+#include "utils/acl.h"
+#include "utils/builtins.h"
+#include "utils/guc.h"
+#include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/varlena.h"
+
+#ifdef USE_LDAP
+#ifdef WIN32
+#include <winldap.h>
+#else
+#include <ldap.h>
+#endif
+#endif
+
+
+#define MAX_TOKEN	256
+
+/* callback data for check_network_callback */
+typedef struct check_network_data
+{
+	IPCompareMethod method;		/* test method */
+	SockAddr   *raddr;			/* client's actual address */
+	bool		result;			/* set to true if match */
+} check_network_data;
+
+
+#define token_is_keyword(t, k)	(!t->quoted && strcmp(t->string, k) == 0)
+#define token_matches(t, k)  (strcmp(t->string, k) == 0)
+
+/*
+ * A single string token lexed from a config file, together with whether
+ * the token had been quoted.
+ */
+typedef struct HbaToken
+{
+	char	   *string;
+	bool		quoted;
+} HbaToken;
+
+/*
+ * TokenizedLine represents one line lexed from a config file.
+ * Each item in the "fields" list is a sub-list of HbaTokens.
+ * We don't emit a TokenizedLine for empty or all-comment lines,
+ * so "fields" is never NIL (nor are any of its sub-lists).
+ * Exception: if an error occurs during tokenization, we might
+ * have fields == NIL, in which case err_msg != NULL.
+ */
+typedef struct TokenizedLine
+{
+	List	   *fields;			/* List of lists of HbaTokens */
+	int			line_num;		/* Line number */
+	char	   *raw_line;		/* Raw line text */
+	char	   *err_msg;		/* Error message if any */
+} TokenizedLine;
+
+/*
+ * pre-parsed content of HBA config file: list of HbaLine structs.
+ * parsed_hba_context is the memory context where it lives.
+ */
+static List *parsed_hba_lines = NIL;
+static MemoryContext parsed_hba_context = NULL;
+
+/*
+ * pre-parsed content of ident mapping file: list of IdentLine structs.
+ * parsed_ident_context is the memory context where it lives.
+ *
+ * NOTE: the IdentLine structs can contain pre-compiled regular expressions
+ * that live outside the memory context. Before destroying or resetting the
+ * memory context, they need to be explicitly free'd.
+ */
+static List *parsed_ident_lines = NIL;
+static MemoryContext parsed_ident_context = NULL;
+
+/*
+ * The following character array represents the names of the authentication
+ * methods that are supported by PostgreSQL.
+ *
+ * Note: keep this in sync with the UserAuth enum in hba.h.
+ */
+static const char *const UserAuthName[] =
+{
+	"reject",
+	"implicit reject",			/* Not a user-visible option */
+	"trust",
+	"ident",
+	"password",
+	"md5",
+	"scram-sha-256",
+	"gss",
+	"sspi",
+	"pam",
+	"bsd",
+	"ldap",
+	"cert",
+	"radius",
+	"peer"
+};
+
+
+static MemoryContext tokenize_file(const char *filename, FILE *file,
+								   List **tok_lines, int elevel);
+static List *tokenize_inc_file(List *tokens, const char *outer_filename,
+							   const char *inc_filename, int elevel, char **err_msg);
+static bool parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline,
+							   int elevel, char **err_msg);
+static ArrayType *gethba_options(HbaLine *hba);
+static void fill_hba_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,
+						  int lineno, HbaLine *hba, const char *err_msg);
+static void fill_hba_view(Tuplestorestate *tuple_store, TupleDesc tupdesc);
+
+
+/*
+ * isblank() exists in the ISO C99 spec, but it's not very portable yet,
+ * so provide our own version.
+ */
+bool
+pg_isblank(const char c)
+{
+	return c == ' ' || c == '\t' || c == '\r';
+}
+
+
+/*
+ * Grab one token out of the string pointed to by *lineptr.
+ *
+ * Tokens are strings of non-blank characters bounded by blank characters,
+ * commas, beginning of line, and end of line.  Blank means space or tab.
+ *
+ * Tokens can be delimited by double quotes (this allows the inclusion of
+ * blanks or '#', but not newlines).  As in SQL, write two double-quotes
+ * to represent a double quote.
+ *
+ * Comments (started by an unquoted '#') are skipped, i.e. the remainder
+ * of the line is ignored.
+ *
+ * (Note that line continuation processing happens before tokenization.
+ * Thus, if a continuation occurs within quoted text or a comment, the
+ * quoted text or comment is considered to continue to the next line.)
+ *
+ * The token, if any, is returned at *buf (a buffer of size bufsz), and
+ * *lineptr is advanced past the token.
+ *
+ * Also, we set *initial_quote to indicate whether there was quoting before
+ * the first character.  (We use that to prevent "@x" from being treated
+ * as a file inclusion request.  Note that @"x" should be so treated;
+ * we want to allow that to support embedded spaces in file paths.)
+ *
+ * We set *terminating_comma to indicate whether the token is terminated by a
+ * comma (which is not returned).
+ *
+ * In event of an error, log a message at ereport level elevel, and also
+ * set *err_msg to a string describing the error.  Currently the only
+ * possible error is token too long for buf.
+ *
+ * If successful: store null-terminated token at *buf and return true.
+ * If no more tokens on line: set *buf = '\0' and return false.
+ * If error: fill buf with truncated or misformatted token and return false.
+ */
+static bool
+next_token(char **lineptr, char *buf, int bufsz,
+		   bool *initial_quote, bool *terminating_comma,
+		   int elevel, char **err_msg)
+{
+	int			c;
+	char	   *start_buf = buf;
+	char	   *end_buf = buf + (bufsz - 1);
+	bool		in_quote = false;
+	bool		was_quote = false;
+	bool		saw_quote = false;
+
+	Assert(end_buf > start_buf);
+
+	*initial_quote = false;
+	*terminating_comma = false;
+
+	/* Move over any whitespace and commas preceding the next token */
+	while ((c = (*(*lineptr)++)) != '\0' && (pg_isblank(c) || c == ','))
+		;
+
+	/*
+	 * Build a token in buf of next characters up to EOL, unquoted comma, or
+	 * unquoted whitespace.
+	 */
+	while (c != '\0' &&
+		   (!pg_isblank(c) || in_quote))
+	{
+		/* skip comments to EOL */
+		if (c == '#' && !in_quote)
+		{
+			while ((c = (*(*lineptr)++)) != '\0')
+				;
+			break;
+		}
+
+		if (buf >= end_buf)
+		{
+			*buf = '\0';
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("authentication file token too long, skipping: \"%s\"",
+							start_buf)));
+			*err_msg = "authentication file token too long";
+			/* Discard remainder of line */
+			while ((c = (*(*lineptr)++)) != '\0')
+				;
+			/* Un-eat the '\0', in case we're called again */
+			(*lineptr)--;
+			return false;
+		}
+
+		/* we do not pass back a terminating comma in the token */
+		if (c == ',' && !in_quote)
+		{
+			*terminating_comma = true;
+			break;
+		}
+
+		if (c != '"' || was_quote)
+			*buf++ = c;
+
+		/* Literal double-quote is two double-quotes */
+		if (in_quote && c == '"')
+			was_quote = !was_quote;
+		else
+			was_quote = false;
+
+		if (c == '"')
+		{
+			in_quote = !in_quote;
+			saw_quote = true;
+			if (buf == start_buf)
+				*initial_quote = true;
+		}
+
+		c = *(*lineptr)++;
+	}
+
+	/*
+	 * Un-eat the char right after the token (critical in case it is '\0',
+	 * else next call will read past end of string).
+	 */
+	(*lineptr)--;
+
+	*buf = '\0';
+
+	return (saw_quote || buf > start_buf);
+}
+
+/*
+ * Construct a palloc'd HbaToken struct, copying the given string.
+ */
+static HbaToken *
+make_hba_token(const char *token, bool quoted)
+{
+	HbaToken   *hbatoken;
+	int			toklen;
+
+	toklen = strlen(token);
+	/* we copy string into same palloc block as the struct */
+	hbatoken = (HbaToken *) palloc(sizeof(HbaToken) + toklen + 1);
+	hbatoken->string = (char *) hbatoken + sizeof(HbaToken);
+	hbatoken->quoted = quoted;
+	memcpy(hbatoken->string, token, toklen + 1);
+
+	return hbatoken;
+}
+
+/*
+ * Copy a HbaToken struct into freshly palloc'd memory.
+ */
+static HbaToken *
+copy_hba_token(HbaToken *in)
+{
+	HbaToken   *out = make_hba_token(in->string, in->quoted);
+
+	return out;
+}
+
+
+/*
+ * Tokenize one HBA field from a line, handling file inclusion and comma lists.
+ *
+ * filename: current file's pathname (needed to resolve relative pathnames)
+ * *lineptr: current line pointer, which will be advanced past field
+ *
+ * In event of an error, log a message at ereport level elevel, and also
+ * set *err_msg to a string describing the error.  Note that the result
+ * may be non-NIL anyway, so *err_msg must be tested to determine whether
+ * there was an error.
+ *
+ * The result is a List of HbaToken structs, one for each token in the field,
+ * or NIL if we reached EOL.
+ */
+static List *
+next_field_expand(const char *filename, char **lineptr,
+				  int elevel, char **err_msg)
+{
+	char		buf[MAX_TOKEN];
+	bool		trailing_comma;
+	bool		initial_quote;
+	List	   *tokens = NIL;
+
+	do
+	{
+		if (!next_token(lineptr, buf, sizeof(buf),
+						&initial_quote, &trailing_comma,
+						elevel, err_msg))
+			break;
+
+		/* Is this referencing a file? */
+		if (!initial_quote && buf[0] == '@' && buf[1] != '\0')
+			tokens = tokenize_inc_file(tokens, filename, buf + 1,
+									   elevel, err_msg);
+		else
+			tokens = lappend(tokens, make_hba_token(buf, initial_quote));
+	} while (trailing_comma && (*err_msg == NULL));
+
+	return tokens;
+}
+
+/*
+ * tokenize_inc_file
+ *		Expand a file included from another file into an hba "field"
+ *
+ * Opens and tokenises a file included from another HBA config file with @,
+ * and returns all values found therein as a flat list of HbaTokens.  If a
+ * @-token is found, recursively expand it.  The newly read tokens are
+ * appended to "tokens" (so that foo,bar,@baz does what you expect).
+ * All new tokens are allocated in caller's memory context.
+ *
+ * In event of an error, log a message at ereport level elevel, and also
+ * set *err_msg to a string describing the error.  Note that the result
+ * may be non-NIL anyway, so *err_msg must be tested to determine whether
+ * there was an error.
+ */
+static List *
+tokenize_inc_file(List *tokens,
+				  const char *outer_filename,
+				  const char *inc_filename,
+				  int elevel,
+				  char **err_msg)
+{
+	char	   *inc_fullname;
+	FILE	   *inc_file;
+	List	   *inc_lines;
+	ListCell   *inc_line;
+	MemoryContext linecxt;
+
+	if (is_absolute_path(inc_filename))
+	{
+		/* absolute path is taken as-is */
+		inc_fullname = pstrdup(inc_filename);
+	}
+	else
+	{
+		/* relative path is relative to dir of calling file */
+		inc_fullname = (char *) palloc(strlen(outer_filename) + 1 +
+									   strlen(inc_filename) + 1);
+		strcpy(inc_fullname, outer_filename);
+		get_parent_directory(inc_fullname);
+		join_path_components(inc_fullname, inc_fullname, inc_filename);
+		canonicalize_path(inc_fullname);
+	}
+
+	inc_file = AllocateFile(inc_fullname, "r");
+	if (inc_file == NULL)
+	{
+		int			save_errno = errno;
+
+		ereport(elevel,
+				(errcode_for_file_access(),
+				 errmsg("could not open secondary authentication file \"@%s\" as \"%s\": %m",
+						inc_filename, inc_fullname)));
+		*err_msg = psprintf("could not open secondary authentication file \"@%s\" as \"%s\": %s",
+							inc_filename, inc_fullname, strerror(save_errno));
+		pfree(inc_fullname);
+		return tokens;
+	}
+
+	/* There is possible recursion here if the file contains @ */
+	linecxt = tokenize_file(inc_fullname, inc_file, &inc_lines, elevel);
+
+	FreeFile(inc_file);
+	pfree(inc_fullname);
+
+	/* Copy all tokens found in the file and append to the tokens list */
+	foreach(inc_line, inc_lines)
+	{
+		TokenizedLine *tok_line = (TokenizedLine *) lfirst(inc_line);
+		ListCell   *inc_field;
+
+		/* If any line has an error, propagate that up to caller */
+		if (tok_line->err_msg)
+		{
+			*err_msg = pstrdup(tok_line->err_msg);
+			break;
+		}
+
+		foreach(inc_field, tok_line->fields)
+		{
+			List	   *inc_tokens = lfirst(inc_field);
+			ListCell   *inc_token;
+
+			foreach(inc_token, inc_tokens)
+			{
+				HbaToken   *token = lfirst(inc_token);
+
+				tokens = lappend(tokens, copy_hba_token(token));
+			}
+		}
+	}
+
+	MemoryContextDelete(linecxt);
+	return tokens;
+}
+
+/*
+ * Tokenize the given file.
+ *
+ * The output is a list of TokenizedLine structs; see struct definition above.
+ *
+ * filename: the absolute path to the target file
+ * file: the already-opened target file
+ * tok_lines: receives output list
+ * elevel: message logging level
+ *
+ * Errors are reported by logging messages at ereport level elevel and by
+ * adding TokenizedLine structs containing non-null err_msg fields to the
+ * output list.
+ *
+ * Return value is a memory context which contains all memory allocated by
+ * this function (it's a child of caller's context).
+ */
+static MemoryContext
+tokenize_file(const char *filename, FILE *file, List **tok_lines, int elevel)
+{
+	int			line_number = 1;
+	StringInfoData buf;
+	MemoryContext linecxt;
+	MemoryContext oldcxt;
+
+	linecxt = AllocSetContextCreate(CurrentMemoryContext,
+									"tokenize_file",
+									ALLOCSET_SMALL_SIZES);
+	oldcxt = MemoryContextSwitchTo(linecxt);
+
+	initStringInfo(&buf);
+
+	*tok_lines = NIL;
+
+	while (!feof(file) && !ferror(file))
+	{
+		char	   *lineptr;
+		List	   *current_line = NIL;
+		char	   *err_msg = NULL;
+		int			last_backslash_buflen = 0;
+		int			continuations = 0;
+
+		/* Collect the next input line, handling backslash continuations */
+		resetStringInfo(&buf);
+
+		while (pg_get_line_append(file, &buf))
+		{
+			/* Strip trailing newline, including \r in case we're on Windows */
+			buf.len = pg_strip_crlf(buf.data);
+
+			/*
+			 * Check for backslash continuation.  The backslash must be after
+			 * the last place we found a continuation, else two backslashes
+			 * followed by two \n's would behave surprisingly.
+			 */
+			if (buf.len > last_backslash_buflen &&
+				buf.data[buf.len - 1] == '\\')
+			{
+				/* Continuation, so strip it and keep reading */
+				buf.data[--buf.len] = '\0';
+				last_backslash_buflen = buf.len;
+				continuations++;
+				continue;
+			}
+
+			/* Nope, so we have the whole line */
+			break;
+		}
+
+		if (ferror(file))
+		{
+			/* I/O error! */
+			int			save_errno = errno;
+
+			ereport(elevel,
+					(errcode_for_file_access(),
+					 errmsg("could not read file \"%s\": %m", filename)));
+			err_msg = psprintf("could not read file \"%s\": %s",
+							   filename, strerror(save_errno));
+			break;
+		}
+
+		/* Parse fields */
+		lineptr = buf.data;
+		while (*lineptr && err_msg == NULL)
+		{
+			List	   *current_field;
+
+			current_field = next_field_expand(filename, &lineptr,
+											  elevel, &err_msg);
+			/* add field to line, unless we are at EOL or comment start */
+			if (current_field != NIL)
+				current_line = lappend(current_line, current_field);
+		}
+
+		/* Reached EOL; emit line to TokenizedLine list unless it's boring */
+		if (current_line != NIL || err_msg != NULL)
+		{
+			TokenizedLine *tok_line;
+
+			tok_line = (TokenizedLine *) palloc(sizeof(TokenizedLine));
+			tok_line->fields = current_line;
+			tok_line->line_num = line_number;
+			tok_line->raw_line = pstrdup(buf.data);
+			tok_line->err_msg = err_msg;
+			*tok_lines = lappend(*tok_lines, tok_line);
+		}
+
+		line_number += continuations + 1;
+	}
+
+	MemoryContextSwitchTo(oldcxt);
+
+	return linecxt;
+}
+
+
+/*
+ * Does user belong to role?
+ *
+ * userid is the OID of the role given as the attempted login identifier.
+ * We check to see if it is a member of the specified role name.
+ */
+static bool
+is_member(Oid userid, const char *role)
+{
+	Oid			roleid;
+
+	if (!OidIsValid(userid))
+		return false;			/* if user not exist, say "no" */
+
+	roleid = get_role_oid(role, true);
+
+	if (!OidIsValid(roleid))
+		return false;			/* if target role not exist, say "no" */
+
+	/*
+	 * See if user is directly or indirectly a member of role. For this
+	 * purpose, a superuser is not considered to be automatically a member of
+	 * the role, so group auth only applies to explicit membership.
+	 */
+	return is_member_of_role_nosuper(userid, roleid);
+}
+
+/*
+ * Check HbaToken list for a match to role, allowing group names.
+ */
+static bool
+check_role(const char *role, Oid roleid, List *tokens)
+{
+	ListCell   *cell;
+	HbaToken   *tok;
+
+	foreach(cell, tokens)
+	{
+		tok = lfirst(cell);
+		if (!tok->quoted && tok->string[0] == '+')
+		{
+			if (is_member(roleid, tok->string + 1))
+				return true;
+		}
+		else if (token_matches(tok, role) ||
+				 token_is_keyword(tok, "all"))
+			return true;
+	}
+	return false;
+}
+
+/*
+ * Check to see if db/role combination matches HbaToken list.
+ */
+static bool
+check_db(const char *dbname, const char *role, Oid roleid, List *tokens)
+{
+	ListCell   *cell;
+	HbaToken   *tok;
+
+	foreach(cell, tokens)
+	{
+		tok = lfirst(cell);
+		if (am_walsender && !am_db_walsender)
+		{
+			/*
+			 * physical replication walsender connections can only match
+			 * replication keyword
+			 */
+			if (token_is_keyword(tok, "replication"))
+				return true;
+		}
+		else if (token_is_keyword(tok, "all"))
+			return true;
+		else if (token_is_keyword(tok, "sameuser"))
+		{
+			if (strcmp(dbname, role) == 0)
+				return true;
+		}
+		else if (token_is_keyword(tok, "samegroup") ||
+				 token_is_keyword(tok, "samerole"))
+		{
+			if (is_member(roleid, dbname))
+				return true;
+		}
+		else if (token_is_keyword(tok, "replication"))
+			continue;			/* never match this if not walsender */
+		else if (token_matches(tok, dbname))
+			return true;
+	}
+	return false;
+}
+
+static bool
+ipv4eq(struct sockaddr_in *a, struct sockaddr_in *b)
+{
+	return (a->sin_addr.s_addr == b->sin_addr.s_addr);
+}
+
+#ifdef HAVE_IPV6
+
+static bool
+ipv6eq(struct sockaddr_in6 *a, struct sockaddr_in6 *b)
+{
+	int			i;
+
+	for (i = 0; i < 16; i++)
+		if (a->sin6_addr.s6_addr[i] != b->sin6_addr.s6_addr[i])
+			return false;
+
+	return true;
+}
+#endif							/* HAVE_IPV6 */
+
+/*
+ * Check whether host name matches pattern.
+ */
+static bool
+hostname_match(const char *pattern, const char *actual_hostname)
+{
+	if (pattern[0] == '.')		/* suffix match */
+	{
+		size_t		plen = strlen(pattern);
+		size_t		hlen = strlen(actual_hostname);
+
+		if (hlen < plen)
+			return false;
+
+		return (pg_strcasecmp(pattern, actual_hostname + (hlen - plen)) == 0);
+	}
+	else
+		return (pg_strcasecmp(pattern, actual_hostname) == 0);
+}
+
+/*
+ * Check to see if a connecting IP matches a given host name.
+ */
+static bool
+check_hostname(hbaPort *port, const char *hostname)
+{
+	struct addrinfo *gai_result,
+			   *gai;
+	int			ret;
+	bool		found;
+
+	/* Quick out if remote host name already known bad */
+	if (port->remote_hostname_resolv < 0)
+		return false;
+
+	/* Lookup remote host name if not already done */
+	if (!port->remote_hostname)
+	{
+		char		remote_hostname[NI_MAXHOST];
+
+		ret = pg_getnameinfo_all(&port->raddr.addr, port->raddr.salen,
+								 remote_hostname, sizeof(remote_hostname),
+								 NULL, 0,
+								 NI_NAMEREQD);
+		if (ret != 0)
+		{
+			/* remember failure; don't complain in the postmaster log yet */
+			port->remote_hostname_resolv = -2;
+			port->remote_hostname_errcode = ret;
+			return false;
+		}
+
+		port->remote_hostname = pstrdup(remote_hostname);
+	}
+
+	/* Now see if remote host name matches this pg_hba line */
+	if (!hostname_match(hostname, port->remote_hostname))
+		return false;
+
+	/* If we already verified the forward lookup, we're done */
+	if (port->remote_hostname_resolv == +1)
+		return true;
+
+	/* Lookup IP from host name and check against original IP */
+	ret = getaddrinfo(port->remote_hostname, NULL, NULL, &gai_result);
+	if (ret != 0)
+	{
+		/* remember failure; don't complain in the postmaster log yet */
+		port->remote_hostname_resolv = -2;
+		port->remote_hostname_errcode = ret;
+		return false;
+	}
+
+	found = false;
+	for (gai = gai_result; gai; gai = gai->ai_next)
+	{
+		if (gai->ai_addr->sa_family == port->raddr.addr.ss_family)
+		{
+			if (gai->ai_addr->sa_family == AF_INET)
+			{
+				if (ipv4eq((struct sockaddr_in *) gai->ai_addr,
+						   (struct sockaddr_in *) &port->raddr.addr))
+				{
+					found = true;
+					break;
+				}
+			}
+#ifdef HAVE_IPV6
+			else if (gai->ai_addr->sa_family == AF_INET6)
+			{
+				if (ipv6eq((struct sockaddr_in6 *) gai->ai_addr,
+						   (struct sockaddr_in6 *) &port->raddr.addr))
+				{
+					found = true;
+					break;
+				}
+			}
+#endif
+		}
+	}
+
+	if (gai_result)
+		freeaddrinfo(gai_result);
+
+	if (!found)
+		elog(DEBUG2, "pg_hba.conf host name \"%s\" rejected because address resolution did not return a match with IP address of client",
+			 hostname);
+
+	port->remote_hostname_resolv = found ? +1 : -1;
+
+	return found;
+}
+
+/*
+ * Check to see if a connecting IP matches the given address and netmask.
+ */
+static bool
+check_ip(SockAddr *raddr, struct sockaddr *addr, struct sockaddr *mask)
+{
+	if (raddr->addr.ss_family == addr->sa_family &&
+		pg_range_sockaddr(&raddr->addr,
+						  (struct sockaddr_storage *) addr,
+						  (struct sockaddr_storage *) mask))
+		return true;
+	return false;
+}
+
+/*
+ * pg_foreach_ifaddr callback: does client addr match this machine interface?
+ */
+static void
+check_network_callback(struct sockaddr *addr, struct sockaddr *netmask,
+					   void *cb_data)
+{
+	check_network_data *cn = (check_network_data *) cb_data;
+	struct sockaddr_storage mask;
+
+	/* Already found a match? */
+	if (cn->result)
+		return;
+
+	if (cn->method == ipCmpSameHost)
+	{
+		/* Make an all-ones netmask of appropriate length for family */
+		pg_sockaddr_cidr_mask(&mask, NULL, addr->sa_family);
+		cn->result = check_ip(cn->raddr, addr, (struct sockaddr *) &mask);
+	}
+	else
+	{
+		/* Use the netmask of the interface itself */
+		cn->result = check_ip(cn->raddr, addr, netmask);
+	}
+}
+
+/*
+ * Use pg_foreach_ifaddr to check a samehost or samenet match
+ */
+static bool
+check_same_host_or_net(SockAddr *raddr, IPCompareMethod method)
+{
+	check_network_data cn;
+
+	cn.method = method;
+	cn.raddr = raddr;
+	cn.result = false;
+
+	errno = 0;
+	if (pg_foreach_ifaddr(check_network_callback, &cn) < 0)
+	{
+		ereport(LOG,
+				(errmsg("error enumerating network interfaces: %m")));
+		return false;
+	}
+
+	return cn.result;
+}
+
+
+/*
+ * Macros used to check and report on invalid configuration options.
+ * On error: log a message at level elevel, set *err_msg, and exit the function.
+ * These macros are not as general-purpose as they look, because they know
+ * what the calling function's error-exit value is.
+ *
+ * INVALID_AUTH_OPTION = reports when an option is specified for a method where it's
+ *						 not supported.
+ * REQUIRE_AUTH_OPTION = same as INVALID_AUTH_OPTION, except it also checks if the
+ *						 method is actually the one specified. Used as a shortcut when
+ *						 the option is only valid for one authentication method.
+ * MANDATORY_AUTH_ARG  = check if a required option is set for an authentication method,
+ *						 reporting error if it's not.
+ */
+#define INVALID_AUTH_OPTION(optname, validmethods) \
+do { \
+	ereport(elevel, \
+			(errcode(ERRCODE_CONFIG_FILE_ERROR), \
+			 /* translator: the second %s is a list of auth methods */ \
+			 errmsg("authentication option \"%s\" is only valid for authentication methods %s", \
+					optname, _(validmethods)), \
+			 errcontext("line %d of configuration file \"%s\"", \
+					line_num, HbaFileName))); \
+	*err_msg = psprintf("authentication option \"%s\" is only valid for authentication methods %s", \
+						optname, validmethods); \
+	return false; \
+} while (0)
+
+#define REQUIRE_AUTH_OPTION(methodval, optname, validmethods) \
+do { \
+	if (hbaline->auth_method != methodval) \
+		INVALID_AUTH_OPTION(optname, validmethods); \
+} while (0)
+
+#define MANDATORY_AUTH_ARG(argvar, argname, authname) \
+do { \
+	if (argvar == NULL) { \
+		ereport(elevel, \
+				(errcode(ERRCODE_CONFIG_FILE_ERROR), \
+				 errmsg("authentication method \"%s\" requires argument \"%s\" to be set", \
+						authname, argname), \
+				 errcontext("line %d of configuration file \"%s\"", \
+						line_num, HbaFileName))); \
+		*err_msg = psprintf("authentication method \"%s\" requires argument \"%s\" to be set", \
+							authname, argname); \
+		return NULL; \
+	} \
+} while (0)
+
+/*
+ * Macros for handling pg_ident problems.
+ * Much as above, but currently the message level is hardwired as LOG
+ * and there is no provision for an err_msg string.
+ *
+ * IDENT_FIELD_ABSENT:
+ * Log a message and exit the function if the given ident field ListCell is
+ * not populated.
+ *
+ * IDENT_MULTI_VALUE:
+ * Log a message and exit the function if the given ident token List has more
+ * than one element.
+ */
+#define IDENT_FIELD_ABSENT(field) \
+do { \
+	if (!field) { \
+		ereport(LOG, \
+				(errcode(ERRCODE_CONFIG_FILE_ERROR), \
+				 errmsg("missing entry in file \"%s\" at end of line %d", \
+						IdentFileName, line_num))); \
+		return NULL; \
+	} \
+} while (0)
+
+#define IDENT_MULTI_VALUE(tokens) \
+do { \
+	if (tokens->length > 1) { \
+		ereport(LOG, \
+				(errcode(ERRCODE_CONFIG_FILE_ERROR), \
+				 errmsg("multiple values in ident field"), \
+				 errcontext("line %d of configuration file \"%s\"", \
+							line_num, IdentFileName))); \
+		return NULL; \
+	} \
+} while (0)
+
+
+/*
+ * Parse one tokenised line from the hba config file and store the result in a
+ * HbaLine structure.
+ *
+ * If parsing fails, log a message at ereport level elevel, store an error
+ * string in tok_line->err_msg, and return NULL.  (Some non-error conditions
+ * can also result in such messages.)
+ *
+ * Note: this function leaks memory when an error occurs.  Caller is expected
+ * to have set a memory context that will be reset if this function returns
+ * NULL.
+ */
+static HbaLine *
+parse_hba_line(TokenizedLine *tok_line, int elevel)
+{
+	int			line_num = tok_line->line_num;
+	char	  **err_msg = &tok_line->err_msg;
+	char	   *str;
+	struct addrinfo *gai_result;
+	struct addrinfo hints;
+	int			ret;
+	char	   *cidr_slash;
+	char	   *unsupauth;
+	ListCell   *field;
+	List	   *tokens;
+	ListCell   *tokencell;
+	HbaToken   *token;
+	HbaLine    *parsedline;
+
+	parsedline = palloc0(sizeof(HbaLine));
+	parsedline->linenumber = line_num;
+	parsedline->rawline = pstrdup(tok_line->raw_line);
+
+	/* Check the record type. */
+	Assert(tok_line->fields != NIL);
+	field = list_head(tok_line->fields);
+	tokens = lfirst(field);
+	if (tokens->length > 1)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("multiple values specified for connection type"),
+				 errhint("Specify exactly one connection type per line."),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "multiple values specified for connection type";
+		return NULL;
+	}
+	token = linitial(tokens);
+	if (strcmp(token->string, "local") == 0)
+	{
+#ifdef HAVE_UNIX_SOCKETS
+		parsedline->conntype = ctLocal;
+#else
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("local connections are not supported by this build"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "local connections are not supported by this build";
+		return NULL;
+#endif
+	}
+	else if (strcmp(token->string, "host") == 0 ||
+			 strcmp(token->string, "hostssl") == 0 ||
+			 strcmp(token->string, "hostnossl") == 0 ||
+			 strcmp(token->string, "hostgssenc") == 0 ||
+			 strcmp(token->string, "hostnogssenc") == 0)
+	{
+
+		if (token->string[4] == 's')	/* "hostssl" */
+		{
+			parsedline->conntype = ctHostSSL;
+			/* Log a warning if SSL support is not active */
+#ifdef USE_SSL
+			if (!EnableSSL)
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("hostssl record cannot match because SSL is disabled"),
+						 errhint("Set ssl = on in postgresql.conf."),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				*err_msg = "hostssl record cannot match because SSL is disabled";
+			}
+#else
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("hostssl record cannot match because SSL is not supported by this build"),
+					 errhint("Compile with --with-ssl to use SSL connections."),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "hostssl record cannot match because SSL is not supported by this build";
+#endif
+		}
+		else if (token->string[4] == 'g')	/* "hostgssenc" */
+		{
+			parsedline->conntype = ctHostGSS;
+#ifndef ENABLE_GSS
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("hostgssenc record cannot match because GSSAPI is not supported by this build"),
+					 errhint("Compile with --with-gssapi to use GSSAPI connections."),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "hostgssenc record cannot match because GSSAPI is not supported by this build";
+#endif
+		}
+		else if (token->string[4] == 'n' && token->string[6] == 's')
+			parsedline->conntype = ctHostNoSSL;
+		else if (token->string[4] == 'n' && token->string[6] == 'g')
+			parsedline->conntype = ctHostNoGSS;
+		else
+		{
+			/* "host" */
+			parsedline->conntype = ctHost;
+		}
+	}							/* record type */
+	else
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("invalid connection type \"%s\"",
+						token->string),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid connection type \"%s\"", token->string);
+		return NULL;
+	}
+
+	/* Get the databases. */
+	field = lnext(tok_line->fields, field);
+	if (!field)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("end-of-line before database specification"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "end-of-line before database specification";
+		return NULL;
+	}
+	parsedline->databases = NIL;
+	tokens = lfirst(field);
+	foreach(tokencell, tokens)
+	{
+		parsedline->databases = lappend(parsedline->databases,
+										copy_hba_token(lfirst(tokencell)));
+	}
+
+	/* Get the roles. */
+	field = lnext(tok_line->fields, field);
+	if (!field)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("end-of-line before role specification"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "end-of-line before role specification";
+		return NULL;
+	}
+	parsedline->roles = NIL;
+	tokens = lfirst(field);
+	foreach(tokencell, tokens)
+	{
+		parsedline->roles = lappend(parsedline->roles,
+									copy_hba_token(lfirst(tokencell)));
+	}
+
+	if (parsedline->conntype != ctLocal)
+	{
+		/* Read the IP address field. (with or without CIDR netmask) */
+		field = lnext(tok_line->fields, field);
+		if (!field)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("end-of-line before IP address specification"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "end-of-line before IP address specification";
+			return NULL;
+		}
+		tokens = lfirst(field);
+		if (tokens->length > 1)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("multiple values specified for host address"),
+					 errhint("Specify one address range per line."),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "multiple values specified for host address";
+			return NULL;
+		}
+		token = linitial(tokens);
+
+		if (token_is_keyword(token, "all"))
+		{
+			parsedline->ip_cmp_method = ipCmpAll;
+		}
+		else if (token_is_keyword(token, "samehost"))
+		{
+			/* Any IP on this host is allowed to connect */
+			parsedline->ip_cmp_method = ipCmpSameHost;
+		}
+		else if (token_is_keyword(token, "samenet"))
+		{
+			/* Any IP on the host's subnets is allowed to connect */
+			parsedline->ip_cmp_method = ipCmpSameNet;
+		}
+		else
+		{
+			/* IP and netmask are specified */
+			parsedline->ip_cmp_method = ipCmpMask;
+
+			/* need a modifiable copy of token */
+			str = pstrdup(token->string);
+
+			/* Check if it has a CIDR suffix and if so isolate it */
+			cidr_slash = strchr(str, '/');
+			if (cidr_slash)
+				*cidr_slash = '\0';
+
+			/* Get the IP address either way */
+			hints.ai_flags = AI_NUMERICHOST;
+			hints.ai_family = AF_UNSPEC;
+			hints.ai_socktype = 0;
+			hints.ai_protocol = 0;
+			hints.ai_addrlen = 0;
+			hints.ai_canonname = NULL;
+			hints.ai_addr = NULL;
+			hints.ai_next = NULL;
+
+			ret = pg_getaddrinfo_all(str, NULL, &hints, &gai_result);
+			if (ret == 0 && gai_result)
+			{
+				memcpy(&parsedline->addr, gai_result->ai_addr,
+					   gai_result->ai_addrlen);
+				parsedline->addrlen = gai_result->ai_addrlen;
+			}
+			else if (ret == EAI_NONAME)
+				parsedline->hostname = str;
+			else
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("invalid IP address \"%s\": %s",
+								str, gai_strerror(ret)),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				*err_msg = psprintf("invalid IP address \"%s\": %s",
+									str, gai_strerror(ret));
+				if (gai_result)
+					pg_freeaddrinfo_all(hints.ai_family, gai_result);
+				return NULL;
+			}
+
+			pg_freeaddrinfo_all(hints.ai_family, gai_result);
+
+			/* Get the netmask */
+			if (cidr_slash)
+			{
+				if (parsedline->hostname)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("specifying both host name and CIDR mask is invalid: \"%s\"",
+									token->string),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = psprintf("specifying both host name and CIDR mask is invalid: \"%s\"",
+										token->string);
+					return NULL;
+				}
+
+				if (pg_sockaddr_cidr_mask(&parsedline->mask, cidr_slash + 1,
+										  parsedline->addr.ss_family) < 0)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("invalid CIDR mask in address \"%s\"",
+									token->string),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = psprintf("invalid CIDR mask in address \"%s\"",
+										token->string);
+					return NULL;
+				}
+				parsedline->masklen = parsedline->addrlen;
+				pfree(str);
+			}
+			else if (!parsedline->hostname)
+			{
+				/* Read the mask field. */
+				pfree(str);
+				field = lnext(tok_line->fields, field);
+				if (!field)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("end-of-line before netmask specification"),
+							 errhint("Specify an address range in CIDR notation, or provide a separate netmask."),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = "end-of-line before netmask specification";
+					return NULL;
+				}
+				tokens = lfirst(field);
+				if (tokens->length > 1)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("multiple values specified for netmask"),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = "multiple values specified for netmask";
+					return NULL;
+				}
+				token = linitial(tokens);
+
+				ret = pg_getaddrinfo_all(token->string, NULL,
+										 &hints, &gai_result);
+				if (ret || !gai_result)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("invalid IP mask \"%s\": %s",
+									token->string, gai_strerror(ret)),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = psprintf("invalid IP mask \"%s\": %s",
+										token->string, gai_strerror(ret));
+					if (gai_result)
+						pg_freeaddrinfo_all(hints.ai_family, gai_result);
+					return NULL;
+				}
+
+				memcpy(&parsedline->mask, gai_result->ai_addr,
+					   gai_result->ai_addrlen);
+				parsedline->masklen = gai_result->ai_addrlen;
+				pg_freeaddrinfo_all(hints.ai_family, gai_result);
+
+				if (parsedline->addr.ss_family != parsedline->mask.ss_family)
+				{
+					ereport(elevel,
+							(errcode(ERRCODE_CONFIG_FILE_ERROR),
+							 errmsg("IP address and mask do not match"),
+							 errcontext("line %d of configuration file \"%s\"",
+										line_num, HbaFileName)));
+					*err_msg = "IP address and mask do not match";
+					return NULL;
+				}
+			}
+		}
+	}							/* != ctLocal */
+
+	/* Get the authentication method */
+	field = lnext(tok_line->fields, field);
+	if (!field)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("end-of-line before authentication method"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "end-of-line before authentication method";
+		return NULL;
+	}
+	tokens = lfirst(field);
+	if (tokens->length > 1)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("multiple values specified for authentication type"),
+				 errhint("Specify exactly one authentication type per line."),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "multiple values specified for authentication type";
+		return NULL;
+	}
+	token = linitial(tokens);
+
+	unsupauth = NULL;
+	if (strcmp(token->string, "trust") == 0)
+		parsedline->auth_method = uaTrust;
+	else if (strcmp(token->string, "ident") == 0)
+		parsedline->auth_method = uaIdent;
+	else if (strcmp(token->string, "peer") == 0)
+		parsedline->auth_method = uaPeer;
+	else if (strcmp(token->string, "password") == 0)
+		parsedline->auth_method = uaPassword;
+	else if (strcmp(token->string, "gss") == 0)
+#ifdef ENABLE_GSS
+		parsedline->auth_method = uaGSS;
+#else
+		unsupauth = "gss";
+#endif
+	else if (strcmp(token->string, "sspi") == 0)
+#ifdef ENABLE_SSPI
+		parsedline->auth_method = uaSSPI;
+#else
+		unsupauth = "sspi";
+#endif
+	else if (strcmp(token->string, "reject") == 0)
+		parsedline->auth_method = uaReject;
+	else if (strcmp(token->string, "md5") == 0)
+	{
+		if (Db_user_namespace)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("MD5 authentication is not supported when \"db_user_namespace\" is enabled"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "MD5 authentication is not supported when \"db_user_namespace\" is enabled";
+			return NULL;
+		}
+		parsedline->auth_method = uaMD5;
+	}
+	else if (strcmp(token->string, "scram-sha-256") == 0)
+		parsedline->auth_method = uaSCRAM;
+	else if (strcmp(token->string, "pam") == 0)
+#ifdef USE_PAM
+		parsedline->auth_method = uaPAM;
+#else
+		unsupauth = "pam";
+#endif
+	else if (strcmp(token->string, "bsd") == 0)
+#ifdef USE_BSD_AUTH
+		parsedline->auth_method = uaBSD;
+#else
+		unsupauth = "bsd";
+#endif
+	else if (strcmp(token->string, "ldap") == 0)
+#ifdef USE_LDAP
+		parsedline->auth_method = uaLDAP;
+#else
+		unsupauth = "ldap";
+#endif
+	else if (strcmp(token->string, "cert") == 0)
+#ifdef USE_SSL
+		parsedline->auth_method = uaCert;
+#else
+		unsupauth = "cert";
+#endif
+	else if (strcmp(token->string, "radius") == 0)
+		parsedline->auth_method = uaRADIUS;
+	else
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("invalid authentication method \"%s\"",
+						token->string),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid authentication method \"%s\"",
+							token->string);
+		return NULL;
+	}
+
+	if (unsupauth)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("invalid authentication method \"%s\": not supported by this build",
+						token->string),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = psprintf("invalid authentication method \"%s\": not supported by this build",
+							token->string);
+		return NULL;
+	}
+
+	/*
+	 * XXX: When using ident on local connections, change it to peer, for
+	 * backwards compatibility.
+	 */
+	if (parsedline->conntype == ctLocal &&
+		parsedline->auth_method == uaIdent)
+		parsedline->auth_method = uaPeer;
+
+	/* Invalid authentication combinations */
+	if (parsedline->conntype == ctLocal &&
+		parsedline->auth_method == uaGSS)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("gssapi authentication is not supported on local sockets"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "gssapi authentication is not supported on local sockets";
+		return NULL;
+	}
+
+	if (parsedline->conntype != ctLocal &&
+		parsedline->auth_method == uaPeer)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("peer authentication is only supported on local sockets"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "peer authentication is only supported on local sockets";
+		return NULL;
+	}
+
+	/*
+	 * SSPI authentication can never be enabled on ctLocal connections,
+	 * because it's only supported on Windows, where ctLocal isn't supported.
+	 */
+
+
+	if (parsedline->conntype != ctHostSSL &&
+		parsedline->auth_method == uaCert)
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("cert authentication is only supported on hostssl connections"),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = "cert authentication is only supported on hostssl connections";
+		return NULL;
+	}
+
+	/*
+	 * For GSS and SSPI, set the default value of include_realm to true.
+	 * Having include_realm set to false is dangerous in multi-realm
+	 * situations and is generally considered bad practice.  We keep the
+	 * capability around for backwards compatibility, but we might want to
+	 * remove it at some point in the future.  Users who still need to strip
+	 * the realm off would be better served by using an appropriate regex in a
+	 * pg_ident.conf mapping.
+	 */
+	if (parsedline->auth_method == uaGSS ||
+		parsedline->auth_method == uaSSPI)
+		parsedline->include_realm = true;
+
+	/*
+	 * For SSPI, include_realm defaults to the SAM-compatible domain (aka
+	 * NetBIOS name) and user names instead of the Kerberos principal name for
+	 * compatibility.
+	 */
+	if (parsedline->auth_method == uaSSPI)
+	{
+		parsedline->compat_realm = true;
+		parsedline->upn_username = false;
+	}
+
+	/* Parse remaining arguments */
+	while ((field = lnext(tok_line->fields, field)) != NULL)
+	{
+		tokens = lfirst(field);
+		foreach(tokencell, tokens)
+		{
+			char	   *val;
+
+			token = lfirst(tokencell);
+
+			str = pstrdup(token->string);
+			val = strchr(str, '=');
+			if (val == NULL)
+			{
+				/*
+				 * Got something that's not a name=value pair.
+				 */
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("authentication option not in name=value format: %s", token->string),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				*err_msg = psprintf("authentication option not in name=value format: %s",
+									token->string);
+				return NULL;
+			}
+
+			*val++ = '\0';		/* str now holds "name", val holds "value" */
+			if (!parse_hba_auth_opt(str, val, parsedline, elevel, err_msg))
+				/* parse_hba_auth_opt already logged the error message */
+				return NULL;
+			pfree(str);
+		}
+	}
+
+	/*
+	 * Check if the selected authentication method has any mandatory arguments
+	 * that are not set.
+	 */
+	if (parsedline->auth_method == uaLDAP)
+	{
+#ifndef HAVE_LDAP_INITIALIZE
+		/* Not mandatory for OpenLDAP, because it can use DNS SRV records */
+		MANDATORY_AUTH_ARG(parsedline->ldapserver, "ldapserver", "ldap");
+#endif
+
+		/*
+		 * LDAP can operate in two modes: either with a direct bind, using
+		 * ldapprefix and ldapsuffix, or using a search+bind, using
+		 * ldapbasedn, ldapbinddn, ldapbindpasswd and one of
+		 * ldapsearchattribute or ldapsearchfilter.  Disallow mixing these
+		 * parameters.
+		 */
+		if (parsedline->ldapprefix || parsedline->ldapsuffix)
+		{
+			if (parsedline->ldapbasedn ||
+				parsedline->ldapbinddn ||
+				parsedline->ldapbindpasswd ||
+				parsedline->ldapsearchattribute ||
+				parsedline->ldapsearchfilter)
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("cannot use ldapbasedn, ldapbinddn, ldapbindpasswd, ldapsearchattribute, ldapsearchfilter, or ldapurl together with ldapprefix"),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				*err_msg = "cannot use ldapbasedn, ldapbinddn, ldapbindpasswd, ldapsearchattribute, ldapsearchfilter, or ldapurl together with ldapprefix";
+				return NULL;
+			}
+		}
+		else if (!parsedline->ldapbasedn)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("authentication method \"ldap\" requires argument \"ldapbasedn\", \"ldapprefix\", or \"ldapsuffix\" to be set"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "authentication method \"ldap\" requires argument \"ldapbasedn\", \"ldapprefix\", or \"ldapsuffix\" to be set";
+			return NULL;
+		}
+
+		/*
+		 * When using search+bind, you can either use a simple attribute
+		 * (defaulting to "uid") or a fully custom search filter.  You can't
+		 * do both.
+		 */
+		if (parsedline->ldapsearchattribute && parsedline->ldapsearchfilter)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("cannot use ldapsearchattribute together with ldapsearchfilter"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "cannot use ldapsearchattribute together with ldapsearchfilter";
+			return NULL;
+		}
+	}
+
+	if (parsedline->auth_method == uaRADIUS)
+	{
+		MANDATORY_AUTH_ARG(parsedline->radiusservers, "radiusservers", "radius");
+		MANDATORY_AUTH_ARG(parsedline->radiussecrets, "radiussecrets", "radius");
+
+		if (list_length(parsedline->radiusservers) < 1)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("list of RADIUS servers cannot be empty"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "list of RADIUS servers cannot be empty";
+			return NULL;
+		}
+
+		if (list_length(parsedline->radiussecrets) < 1)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("list of RADIUS secrets cannot be empty"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "list of RADIUS secrets cannot be empty";
+			return NULL;
+		}
+
+		/*
+		 * Verify length of option lists - each can be 0 (except for secrets,
+		 * but that's already checked above), 1 (use the same value
+		 * everywhere) or the same as the number of servers.
+		 */
+		if (!(list_length(parsedline->radiussecrets) == 1 ||
+			  list_length(parsedline->radiussecrets) == list_length(parsedline->radiusservers)))
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("the number of RADIUS secrets (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+							list_length(parsedline->radiussecrets),
+							list_length(parsedline->radiusservers)),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = psprintf("the number of RADIUS secrets (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+								list_length(parsedline->radiussecrets),
+								list_length(parsedline->radiusservers));
+			return NULL;
+		}
+		if (!(list_length(parsedline->radiusports) == 0 ||
+			  list_length(parsedline->radiusports) == 1 ||
+			  list_length(parsedline->radiusports) == list_length(parsedline->radiusservers)))
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("the number of RADIUS ports (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+							list_length(parsedline->radiusports),
+							list_length(parsedline->radiusservers)),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = psprintf("the number of RADIUS ports (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+								list_length(parsedline->radiusports),
+								list_length(parsedline->radiusservers));
+			return NULL;
+		}
+		if (!(list_length(parsedline->radiusidentifiers) == 0 ||
+			  list_length(parsedline->radiusidentifiers) == 1 ||
+			  list_length(parsedline->radiusidentifiers) == list_length(parsedline->radiusservers)))
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("the number of RADIUS identifiers (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+							list_length(parsedline->radiusidentifiers),
+							list_length(parsedline->radiusservers)),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = psprintf("the number of RADIUS identifiers (%d) must be 1 or the same as the number of RADIUS servers (%d)",
+								list_length(parsedline->radiusidentifiers),
+								list_length(parsedline->radiusservers));
+			return NULL;
+		}
+	}
+
+	/*
+	 * Enforce any parameters implied by other settings.
+	 */
+	if (parsedline->auth_method == uaCert)
+	{
+		/*
+		 * For auth method cert, client certificate validation is mandatory, and it implies
+		 * the level of verify-full.
+		 */
+		parsedline->clientcert = clientCertFull;
+	}
+
+	return parsedline;
+}
+
+
+/*
+ * Parse one name-value pair as an authentication option into the given
+ * HbaLine.  Return true if we successfully parse the option, false if we
+ * encounter an error.  In the event of an error, also log a message at
+ * ereport level elevel, and store a message string into *err_msg.
+ */
+static bool
+parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline,
+				   int elevel, char **err_msg)
+{
+	int			line_num = hbaline->linenumber;
+
+#ifdef USE_LDAP
+	hbaline->ldapscope = LDAP_SCOPE_SUBTREE;
+#endif
+
+	if (strcmp(name, "map") == 0)
+	{
+		if (hbaline->auth_method != uaIdent &&
+			hbaline->auth_method != uaPeer &&
+			hbaline->auth_method != uaGSS &&
+			hbaline->auth_method != uaSSPI &&
+			hbaline->auth_method != uaCert)
+			INVALID_AUTH_OPTION("map", gettext_noop("ident, peer, gssapi, sspi, and cert"));
+		hbaline->usermap = pstrdup(val);
+	}
+	else if (strcmp(name, "clientcert") == 0)
+	{
+		if (hbaline->conntype != ctHostSSL)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("clientcert can only be configured for \"hostssl\" rows"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "clientcert can only be configured for \"hostssl\" rows";
+			return false;
+		}
+
+		if (strcmp(val, "verify-full") == 0)
+		{
+			hbaline->clientcert = clientCertFull;
+		}
+		else if (strcmp(val, "verify-ca") == 0)
+		{
+			if (hbaline->auth_method == uaCert)
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("clientcert only accepts \"verify-full\" when using \"cert\" authentication"),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				*err_msg = "clientcert can only be set to \"verify-full\" when using \"cert\" authentication";
+				return false;
+			}
+
+			hbaline->clientcert = clientCertCA;
+		}
+		else
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("invalid value for clientcert: \"%s\"", val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			return false;
+		}
+	}
+	else if (strcmp(name, "clientname") == 0)
+	{
+		if (hbaline->conntype != ctHostSSL)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("clientname can only be configured for \"hostssl\" rows"),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = "clientname can only be configured for \"hostssl\" rows";
+			return false;
+		}
+
+		if (strcmp(val, "CN") == 0)
+		{
+			hbaline->clientcertname = clientCertCN;
+		}
+		else if (strcmp(val, "DN") == 0)
+		{
+			hbaline->clientcertname = clientCertDN;
+		}
+		else
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("invalid value for clientname: \"%s\"", val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			return false;
+		}
+	}
+	else if (strcmp(name, "pamservice") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaPAM, "pamservice", "pam");
+		hbaline->pamservice = pstrdup(val);
+	}
+	else if (strcmp(name, "pam_use_hostname") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaPAM, "pam_use_hostname", "pam");
+		if (strcmp(val, "1") == 0)
+			hbaline->pam_use_hostname = true;
+		else
+			hbaline->pam_use_hostname = false;
+
+	}
+	else if (strcmp(name, "ldapurl") == 0)
+	{
+#ifdef LDAP_API_FEATURE_X_OPENLDAP
+		LDAPURLDesc *urldata;
+		int			rc;
+#endif
+
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapurl", "ldap");
+#ifdef LDAP_API_FEATURE_X_OPENLDAP
+		rc = ldap_url_parse(val, &urldata);
+		if (rc != LDAP_SUCCESS)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("could not parse LDAP URL \"%s\": %s", val, ldap_err2string(rc))));
+			*err_msg = psprintf("could not parse LDAP URL \"%s\": %s",
+								val, ldap_err2string(rc));
+			return false;
+		}
+
+		if (strcmp(urldata->lud_scheme, "ldap") != 0 &&
+			strcmp(urldata->lud_scheme, "ldaps") != 0)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("unsupported LDAP URL scheme: %s", urldata->lud_scheme)));
+			*err_msg = psprintf("unsupported LDAP URL scheme: %s",
+								urldata->lud_scheme);
+			ldap_free_urldesc(urldata);
+			return false;
+		}
+
+		if (urldata->lud_scheme)
+			hbaline->ldapscheme = pstrdup(urldata->lud_scheme);
+		if (urldata->lud_host)
+			hbaline->ldapserver = pstrdup(urldata->lud_host);
+		hbaline->ldapport = urldata->lud_port;
+		if (urldata->lud_dn)
+			hbaline->ldapbasedn = pstrdup(urldata->lud_dn);
+
+		if (urldata->lud_attrs)
+			hbaline->ldapsearchattribute = pstrdup(urldata->lud_attrs[0]);	/* only use first one */
+		hbaline->ldapscope = urldata->lud_scope;
+		if (urldata->lud_filter)
+			hbaline->ldapsearchfilter = pstrdup(urldata->lud_filter);
+		ldap_free_urldesc(urldata);
+#else							/* not OpenLDAP */
+		ereport(elevel,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("LDAP URLs not supported on this platform")));
+		*err_msg = "LDAP URLs not supported on this platform";
+#endif							/* not OpenLDAP */
+	}
+	else if (strcmp(name, "ldaptls") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldaptls", "ldap");
+		if (strcmp(val, "1") == 0)
+			hbaline->ldaptls = true;
+		else
+			hbaline->ldaptls = false;
+	}
+	else if (strcmp(name, "ldapscheme") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapscheme", "ldap");
+		if (strcmp(val, "ldap") != 0 && strcmp(val, "ldaps") != 0)
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("invalid ldapscheme value: \"%s\"", val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+		hbaline->ldapscheme = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapserver") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapserver", "ldap");
+		hbaline->ldapserver = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapport") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapport", "ldap");
+		hbaline->ldapport = atoi(val);
+		if (hbaline->ldapport == 0)
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("invalid LDAP port number: \"%s\"", val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = psprintf("invalid LDAP port number: \"%s\"", val);
+			return false;
+		}
+	}
+	else if (strcmp(name, "ldapbinddn") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapbinddn", "ldap");
+		hbaline->ldapbinddn = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapbindpasswd") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapbindpasswd", "ldap");
+		hbaline->ldapbindpasswd = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapsearchattribute") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapsearchattribute", "ldap");
+		hbaline->ldapsearchattribute = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapsearchfilter") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapsearchfilter", "ldap");
+		hbaline->ldapsearchfilter = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapbasedn") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapbasedn", "ldap");
+		hbaline->ldapbasedn = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapprefix") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapprefix", "ldap");
+		hbaline->ldapprefix = pstrdup(val);
+	}
+	else if (strcmp(name, "ldapsuffix") == 0)
+	{
+		REQUIRE_AUTH_OPTION(uaLDAP, "ldapsuffix", "ldap");
+		hbaline->ldapsuffix = pstrdup(val);
+	}
+	else if (strcmp(name, "krb_realm") == 0)
+	{
+		if (hbaline->auth_method != uaGSS &&
+			hbaline->auth_method != uaSSPI)
+			INVALID_AUTH_OPTION("krb_realm", gettext_noop("gssapi and sspi"));
+		hbaline->krb_realm = pstrdup(val);
+	}
+	else if (strcmp(name, "include_realm") == 0)
+	{
+		if (hbaline->auth_method != uaGSS &&
+			hbaline->auth_method != uaSSPI)
+			INVALID_AUTH_OPTION("include_realm", gettext_noop("gssapi and sspi"));
+		if (strcmp(val, "1") == 0)
+			hbaline->include_realm = true;
+		else
+			hbaline->include_realm = false;
+	}
+	else if (strcmp(name, "compat_realm") == 0)
+	{
+		if (hbaline->auth_method != uaSSPI)
+			INVALID_AUTH_OPTION("compat_realm", gettext_noop("sspi"));
+		if (strcmp(val, "1") == 0)
+			hbaline->compat_realm = true;
+		else
+			hbaline->compat_realm = false;
+	}
+	else if (strcmp(name, "upn_username") == 0)
+	{
+		if (hbaline->auth_method != uaSSPI)
+			INVALID_AUTH_OPTION("upn_username", gettext_noop("sspi"));
+		if (strcmp(val, "1") == 0)
+			hbaline->upn_username = true;
+		else
+			hbaline->upn_username = false;
+	}
+	else if (strcmp(name, "radiusservers") == 0)
+	{
+		struct addrinfo *gai_result;
+		struct addrinfo hints;
+		int			ret;
+		List	   *parsed_servers;
+		ListCell   *l;
+		char	   *dupval = pstrdup(val);
+
+		REQUIRE_AUTH_OPTION(uaRADIUS, "radiusservers", "radius");
+
+		if (!SplitGUCList(dupval, ',', &parsed_servers))
+		{
+			/* syntax error in list */
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("could not parse RADIUS server list \"%s\"",
+							val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			return false;
+		}
+
+		/* For each entry in the list, translate it */
+		foreach(l, parsed_servers)
+		{
+			MemSet(&hints, 0, sizeof(hints));
+			hints.ai_socktype = SOCK_DGRAM;
+			hints.ai_family = AF_UNSPEC;
+
+			ret = pg_getaddrinfo_all((char *) lfirst(l), NULL, &hints, &gai_result);
+			if (ret || !gai_result)
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("could not translate RADIUS server name \"%s\" to address: %s",
+								(char *) lfirst(l), gai_strerror(ret)),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+				if (gai_result)
+					pg_freeaddrinfo_all(hints.ai_family, gai_result);
+
+				list_free(parsed_servers);
+				return false;
+			}
+			pg_freeaddrinfo_all(hints.ai_family, gai_result);
+		}
+
+		/* All entries are OK, so store them */
+		hbaline->radiusservers = parsed_servers;
+		hbaline->radiusservers_s = pstrdup(val);
+	}
+	else if (strcmp(name, "radiusports") == 0)
+	{
+		List	   *parsed_ports;
+		ListCell   *l;
+		char	   *dupval = pstrdup(val);
+
+		REQUIRE_AUTH_OPTION(uaRADIUS, "radiusports", "radius");
+
+		if (!SplitGUCList(dupval, ',', &parsed_ports))
+		{
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("could not parse RADIUS port list \"%s\"",
+							val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			*err_msg = psprintf("invalid RADIUS port number: \"%s\"", val);
+			return false;
+		}
+
+		foreach(l, parsed_ports)
+		{
+			if (atoi(lfirst(l)) == 0)
+			{
+				ereport(elevel,
+						(errcode(ERRCODE_CONFIG_FILE_ERROR),
+						 errmsg("invalid RADIUS port number: \"%s\"", val),
+						 errcontext("line %d of configuration file \"%s\"",
+									line_num, HbaFileName)));
+
+				return false;
+			}
+		}
+		hbaline->radiusports = parsed_ports;
+		hbaline->radiusports_s = pstrdup(val);
+	}
+	else if (strcmp(name, "radiussecrets") == 0)
+	{
+		List	   *parsed_secrets;
+		char	   *dupval = pstrdup(val);
+
+		REQUIRE_AUTH_OPTION(uaRADIUS, "radiussecrets", "radius");
+
+		if (!SplitGUCList(dupval, ',', &parsed_secrets))
+		{
+			/* syntax error in list */
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("could not parse RADIUS secret list \"%s\"",
+							val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			return false;
+		}
+
+		hbaline->radiussecrets = parsed_secrets;
+		hbaline->radiussecrets_s = pstrdup(val);
+	}
+	else if (strcmp(name, "radiusidentifiers") == 0)
+	{
+		List	   *parsed_identifiers;
+		char	   *dupval = pstrdup(val);
+
+		REQUIRE_AUTH_OPTION(uaRADIUS, "radiusidentifiers", "radius");
+
+		if (!SplitGUCList(dupval, ',', &parsed_identifiers))
+		{
+			/* syntax error in list */
+			ereport(elevel,
+					(errcode(ERRCODE_CONFIG_FILE_ERROR),
+					 errmsg("could not parse RADIUS identifiers list \"%s\"",
+							val),
+					 errcontext("line %d of configuration file \"%s\"",
+								line_num, HbaFileName)));
+			return false;
+		}
+
+		hbaline->radiusidentifiers = parsed_identifiers;
+		hbaline->radiusidentifiers_s = pstrdup(val);
+	}
+	else
+	{
+		ereport(elevel,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("unrecognized authentication option name: \"%s\"",
+						name),
+				 errcontext("line %d of configuration file \"%s\"",
+							line_num, HbaFileName)));
+		*err_msg = psprintf("unrecognized authentication option name: \"%s\"",
+							name);
+		return false;
+	}
+	return true;
+}
+
+/*
+ *	Scan the pre-parsed hba file, looking for a match to the port's connection
+ *	request.
+ */
+static void
+check_hba(hbaPort *port)
+{
+	Oid			roleid;
+	ListCell   *line;
+	HbaLine    *hba;
+
+	/* Get the target role's OID.  Note we do not error out for bad role. */
+	roleid = get_role_oid(port->user_name, true);
+
+	foreach(line, parsed_hba_lines)
+	{
+		hba = (HbaLine *) lfirst(line);
+
+		/* Check connection type */
+		if (hba->conntype == ctLocal)
+		{
+			if (!IS_AF_UNIX(port->raddr.addr.ss_family))
+				continue;
+		}
+		else
+		{
+			if (IS_AF_UNIX(port->raddr.addr.ss_family))
+				continue;
+
+			/* Check SSL state */
+			if (port->ssl_in_use)
+			{
+				/* Connection is SSL, match both "host" and "hostssl" */
+				if (hba->conntype == ctHostNoSSL)
+					continue;
+			}
+			else
+			{
+				/* Connection is not SSL, match both "host" and "hostnossl" */
+				if (hba->conntype == ctHostSSL)
+					continue;
+			}
+
+			/* Check GSSAPI state */
+#ifdef ENABLE_GSS
+			if (port->gss && port->gss->enc &&
+				hba->conntype == ctHostNoGSS)
+				continue;
+			else if (!(port->gss && port->gss->enc) &&
+					 hba->conntype == ctHostGSS)
+				continue;
+#else
+			if (hba->conntype == ctHostGSS)
+				continue;
+#endif
+
+			/* Check IP address */
+			switch (hba->ip_cmp_method)
+			{
+				case ipCmpMask:
+					if (hba->hostname)
+					{
+						if (!check_hostname(port,
+											hba->hostname))
+							continue;
+					}
+					else
+					{
+						if (!check_ip(&port->raddr,
+									  (struct sockaddr *) &hba->addr,
+									  (struct sockaddr *) &hba->mask))
+							continue;
+					}
+					break;
+				case ipCmpAll:
+					break;
+				case ipCmpSameHost:
+				case ipCmpSameNet:
+					if (!check_same_host_or_net(&port->raddr,
+												hba->ip_cmp_method))
+						continue;
+					break;
+				default:
+					/* shouldn't get here, but deem it no-match if so */
+					continue;
+			}
+		}						/* != ctLocal */
+
+		/* Check database and role */
+		if (!check_db(port->database_name, port->user_name, roleid,
+					  hba->databases))
+			continue;
+
+		if (!check_role(port->user_name, roleid, hba->roles))
+			continue;
+
+		/* Found a record that matched! */
+		port->hba = hba;
+		return;
+	}
+
+	/* If no matching entry was found, then implicitly reject. */
+	hba = palloc0(sizeof(HbaLine));
+	hba->auth_method = uaImplicitReject;
+	port->hba = hba;
+}
+
+/*
+ * Read the config file and create a List of HbaLine records for the contents.
+ *
+ * The configuration is read into a temporary list, and if any parse error
+ * occurs the old list is kept in place and false is returned.  Only if the
+ * whole file parses OK is the list replaced, and the function returns true.
+ *
+ * On a false result, caller will take care of reporting a FATAL error in case
+ * this is the initial startup.  If it happens on reload, we just keep running
+ * with the old data.
+ */
+bool
+load_hba(void)
+{
+	FILE	   *file;
+	List	   *hba_lines = NIL;
+	ListCell   *line;
+	List	   *new_parsed_lines = NIL;
+	bool		ok = true;
+	MemoryContext linecxt;
+	MemoryContext oldcxt;
+	MemoryContext hbacxt;
+
+	file = AllocateFile(HbaFileName, "r");
+	if (file == NULL)
+	{
+		ereport(LOG,
+				(errcode_for_file_access(),
+				 errmsg("could not open configuration file \"%s\": %m",
+						HbaFileName)));
+		return false;
+	}
+
+	linecxt = tokenize_file(HbaFileName, file, &hba_lines, LOG);
+	FreeFile(file);
+
+	/* Now parse all the lines */
+	Assert(PostmasterContext);
+	hbacxt = AllocSetContextCreate(PostmasterContext,
+								   "hba parser context",
+								   ALLOCSET_SMALL_SIZES);
+	oldcxt = MemoryContextSwitchTo(hbacxt);
+	foreach(line, hba_lines)
+	{
+		TokenizedLine *tok_line = (TokenizedLine *) lfirst(line);
+		HbaLine    *newline;
+
+		/* don't parse lines that already have errors */
+		if (tok_line->err_msg != NULL)
+		{
+			ok = false;
+			continue;
+		}
+
+		if ((newline = parse_hba_line(tok_line, LOG)) == NULL)
+		{
+			/* Parse error; remember there's trouble */
+			ok = false;
+
+			/*
+			 * Keep parsing the rest of the file so we can report errors on
+			 * more than the first line.  Error has already been logged, no
+			 * need for more chatter here.
+			 */
+			continue;
+		}
+
+		new_parsed_lines = lappend(new_parsed_lines, newline);
+	}
+
+	/*
+	 * A valid HBA file must have at least one entry; else there's no way to
+	 * connect to the postmaster.  But only complain about this if we didn't
+	 * already have parsing errors.
+	 */
+	if (ok && new_parsed_lines == NIL)
+	{
+		ereport(LOG,
+				(errcode(ERRCODE_CONFIG_FILE_ERROR),
+				 errmsg("configuration file \"%s\" contains no entries",
+						HbaFileName)));
+		ok = false;
+	}
+
+	/* Free tokenizer memory */
+	MemoryContextDelete(linecxt);
+	MemoryContextSwitchTo(oldcxt);
+
+	if (!ok)
+	{
+		/* File contained one or more errors, so bail out */
+		MemoryContextDelete(hbacxt);
+		return false;
+	}
+
+	/* Loaded new file successfully, replace the one we use */
+	if (parsed_hba_context != NULL)
+		MemoryContextDelete(parsed_hba_context);
+	parsed_hba_context = hbacxt;
+	parsed_hba_lines = new_parsed_lines;
+
+	return true;
+}
+
+/*
+ * This macro specifies the maximum number of authentication options
+ * that are possible with any given authentication method that is supported.
+ * Currently LDAP supports 11, and there are 3 that are not dependent on
+ * the auth method here.  It may not actually be possible to set all of them
+ * at the same time, but we'll set the macro value high enough to be
+ * conservative and avoid warnings from static analysis tools.
+ */
+#define MAX_HBA_OPTIONS 14
+
+/*
+ * Create a text array listing the options specified in the HBA line.
+ * Return NULL if no options are specified.
+ */
+static ArrayType *
+gethba_options(HbaLine *hba)
+{
+	int			noptions;
+	Datum		options[MAX_HBA_OPTIONS];
+
+	noptions = 0;
+
+	if (hba->auth_method == uaGSS || hba->auth_method == uaSSPI)
+	{
+		if (hba->include_realm)
+			options[noptions++] =
+				CStringGetTextDatum("include_realm=true");
+
+		if (hba->krb_realm)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("krb_realm=%s", hba->krb_realm));
+	}
+
+	if (hba->usermap)
+		options[noptions++] =
+			CStringGetTextDatum(psprintf("map=%s", hba->usermap));
+
+	if (hba->clientcert != clientCertOff)
+		options[noptions++] =
+			CStringGetTextDatum(psprintf("clientcert=%s", (hba->clientcert == clientCertCA) ? "verify-ca" : "verify-full"));
+
+	if (hba->pamservice)
+		options[noptions++] =
+			CStringGetTextDatum(psprintf("pamservice=%s", hba->pamservice));
+
+	if (hba->auth_method == uaLDAP)
+	{
+		if (hba->ldapserver)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapserver=%s", hba->ldapserver));
+
+		if (hba->ldapport)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapport=%d", hba->ldapport));
+
+		if (hba->ldaptls)
+			options[noptions++] =
+				CStringGetTextDatum("ldaptls=true");
+
+		if (hba->ldapprefix)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapprefix=%s", hba->ldapprefix));
+
+		if (hba->ldapsuffix)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapsuffix=%s", hba->ldapsuffix));
+
+		if (hba->ldapbasedn)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapbasedn=%s", hba->ldapbasedn));
+
+		if (hba->ldapbinddn)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapbinddn=%s", hba->ldapbinddn));
+
+		if (hba->ldapbindpasswd)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapbindpasswd=%s",
+											 hba->ldapbindpasswd));
+
+		if (hba->ldapsearchattribute)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapsearchattribute=%s",
+											 hba->ldapsearchattribute));
+
+		if (hba->ldapsearchfilter)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapsearchfilter=%s",
+											 hba->ldapsearchfilter));
+
+		if (hba->ldapscope)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("ldapscope=%d", hba->ldapscope));
+	}
+
+	if (hba->auth_method == uaRADIUS)
+	{
+		if (hba->radiusservers_s)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("radiusservers=%s", hba->radiusservers_s));
+
+		if (hba->radiussecrets_s)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("radiussecrets=%s", hba->radiussecrets_s));
+
+		if (hba->radiusidentifiers_s)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("radiusidentifiers=%s", hba->radiusidentifiers_s));
+
+		if (hba->radiusports_s)
+			options[noptions++] =
+				CStringGetTextDatum(psprintf("radiusports=%s", hba->radiusports_s));
+	}
+
+	/* If you add more options, consider increasing MAX_HBA_OPTIONS. */
+	Assert(noptions <= MAX_HBA_OPTIONS);
+
+	if (noptions > 0)
+		return construct_array(options, noptions, TEXTOID, -1, false, TYPALIGN_INT);
+	else
+		return NULL;
+}
+
+/* Number of columns in pg_hba_file_rules view */
+#define NUM_PG_HBA_FILE_RULES_ATTS	 9
+
+/*
+ * fill_hba_line: build one row of pg_hba_file_rules view, add it to tuplestore
+ *
+ * tuple_store: where to store data
+ * tupdesc: tuple descriptor for the view
+ * lineno: pg_hba.conf line number (must always be valid)
+ * hba: parsed line data (can be NULL, in which case err_msg should be set)
+ * err_msg: error message (NULL if none)
+ *
+ * Note: leaks memory, but we don't care since this is run in a short-lived
+ * memory context.
+ */
+static void
+fill_hba_line(Tuplestorestate *tuple_store, TupleDesc tupdesc,
+			  int lineno, HbaLine *hba, const char *err_msg)
+{
+	Datum		values[NUM_PG_HBA_FILE_RULES_ATTS];
+	bool		nulls[NUM_PG_HBA_FILE_RULES_ATTS];
+	char		buffer[NI_MAXHOST];
+	HeapTuple	tuple;
+	int			index;
+	ListCell   *lc;
+	const char *typestr;
+	const char *addrstr;
+	const char *maskstr;
+	ArrayType  *options;
+
+	Assert(tupdesc->natts == NUM_PG_HBA_FILE_RULES_ATTS);
+
+	memset(values, 0, sizeof(values));
+	memset(nulls, 0, sizeof(nulls));
+	index = 0;
+
+	/* line_number */
+	values[index++] = Int32GetDatum(lineno);
+
+	if (hba != NULL)
+	{
+		/* type */
+		/* Avoid a default: case so compiler will warn about missing cases */
+		typestr = NULL;
+		switch (hba->conntype)
+		{
+			case ctLocal:
+				typestr = "local";
+				break;
+			case ctHost:
+				typestr = "host";
+				break;
+			case ctHostSSL:
+				typestr = "hostssl";
+				break;
+			case ctHostNoSSL:
+				typestr = "hostnossl";
+				break;
+			case ctHostGSS:
+				typestr = "hostgssenc";
+				break;
+			case ctHostNoGSS:
+				typestr = "hostnogssenc";
+				break;
+		}
+		if (typestr)
+			values[index++] = CStringGetTextDatum(typestr);
+		else
+			nulls[index++] = true;
+
+		/* database */
+		if (hba->databases)
+		{
+			/*
+			 * Flatten HbaToken list to string list.  It might seem that we
+			 * should re-quote any quoted tokens, but that has been rejected
+			 * on the grounds that it makes it harder to compare the array
+			 * elements to other system catalogs.  That makes entries like
+			 * "all" or "samerole" formally ambiguous ... but users who name
+			 * databases/roles that way are inflicting their own pain.
+			 */
+			List	   *names = NIL;
+
+			foreach(lc, hba->databases)
+			{
+				HbaToken   *tok = lfirst(lc);
+
+				names = lappend(names, tok->string);
+			}
+			values[index++] = PointerGetDatum(strlist_to_textarray(names));
+		}
+		else
+			nulls[index++] = true;
+
+		/* user */
+		if (hba->roles)
+		{
+			/* Flatten HbaToken list to string list; see comment above */
+			List	   *roles = NIL;
+
+			foreach(lc, hba->roles)
+			{
+				HbaToken   *tok = lfirst(lc);
+
+				roles = lappend(roles, tok->string);
+			}
+			values[index++] = PointerGetDatum(strlist_to_textarray(roles));
+		}
+		else
+			nulls[index++] = true;
+
+		/* address and netmask */
+		/* Avoid a default: case so compiler will warn about missing cases */
+		addrstr = maskstr = NULL;
+		switch (hba->ip_cmp_method)
+		{
+			case ipCmpMask:
+				if (hba->hostname)
+				{
+					addrstr = hba->hostname;
+				}
+				else
+				{
+					/*
+					 * Note: if pg_getnameinfo_all fails, it'll set buffer to
+					 * "???", which we want to return.
+					 */
+					if (hba->addrlen > 0)
+					{
+						if (pg_getnameinfo_all(&hba->addr, hba->addrlen,
+											   buffer, sizeof(buffer),
+											   NULL, 0,
+											   NI_NUMERICHOST) == 0)
+							clean_ipv6_addr(hba->addr.ss_family, buffer);
+						addrstr = pstrdup(buffer);
+					}
+					if (hba->masklen > 0)
+					{
+						if (pg_getnameinfo_all(&hba->mask, hba->masklen,
+											   buffer, sizeof(buffer),
+											   NULL, 0,
+											   NI_NUMERICHOST) == 0)
+							clean_ipv6_addr(hba->mask.ss_family, buffer);
+						maskstr = pstrdup(buffer);
+					}
+				}
+				break;
+			case ipCmpAll:
+				addrstr = "all";
+				break;
+			case ipCmpSameHost:
+				addrstr = "samehost";
+				break;
+			case ipCmpSameNet:
+				addrstr = "samenet";
+				break;
+		}
+		if (addrstr)
+			values[index++] = CStringGetTextDatum(addrstr);
+		else
+			nulls[index++] = true;
+		if (maskstr)
+			values[index++] = CStringGetTextDatum(maskstr);
+		else
+			nulls[index++] = true;
+
+		/* auth_method */
+		values[index++] = CStringGetTextDatum(hba_authname(hba->auth_method));
+
+		/* options */
+		options = gethba_options(hba);
+		if (options)
+			values[index++] = PointerGetDatum(options);
+		else
+			nulls[index++] = true;
+	}
+	else
+	{
+		/* no parsing result, so set relevant fields to nulls */
+		memset(&nulls[1], true, (NUM_PG_HBA_FILE_RULES_ATTS - 2) * sizeof(bool));
+	}
+
+	/* error */
+	if (err_msg)
+		values[NUM_PG_HBA_FILE_RULES_ATTS - 1] = CStringGetTextDatum(err_msg);
+	else
+		nulls[NUM_PG_HBA_FILE_RULES_ATTS - 1] = true;
+
+	tuple = heap_form_tuple(tupdesc, values, nulls);
+	tuplestore_puttuple(tuple_store, tuple);
+}
+
+/*
+ * Read the pg_hba.conf file and fill the tuplestore with view records.
+ */
+static void
+fill_hba_view(Tuplestorestate *tuple_store, TupleDesc tupdesc)
+{
+	FILE	   *file;
+	List	   *hba_lines = NIL;
+	ListCell   *line;
+	MemoryContext linecxt;
+	MemoryContext hbacxt;
+	MemoryContext oldcxt;
+
+	/*
+	 * In the unlikely event that we can't open pg_hba.conf, we throw an
+	 * error, rather than trying to report it via some sort of view entry.
+	 * (Most other error conditions should result in a message in a view
+	 * entry.)
+	 */
+	file = AllocateFile(HbaFileName, "r");
+	if (file == NULL)
+		ereport(ERROR,
+				(errcode_for_file_access(),
+				 errmsg("could not open configuration file \"%s\": %m",
+						HbaFileName)));
+
+	linecxt = tokenize_file(HbaFileName, file, &hba_lines, DEBUG3);
+	FreeFile(file);
+
+	/* Now parse all the lines */
+	hbacxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "hba parser context",
+								   ALLOCSET_SMALL_SIZES);
+	oldcxt = MemoryContextSwitchTo(hbacxt);
+	foreach(line, hba_lines)
+	{
+		TokenizedLine *tok_line = (TokenizedLine *) lfirst(line);
+		HbaLine    *hbaline = NULL;
+
+		/* don't parse lines that already have errors */
+		if (tok_line->err_msg == NULL)
+			hbaline = parse_hba_line(tok_line, DEBUG3);
+
+		fill_hba_line(tuple_store, tupdesc, tok_line->line_num,
+					  hbaline, tok_line->err_msg);
+	}
+
+	/* Free tokenizer memory */
+	MemoryContextDelete(linecxt);
+	/* Free parse_hba_line memory */
+	MemoryContextSwitchTo(oldcxt);
+	MemoryContextDelete(hbacxt);
+}
+
+/*
+ * SQL-accessible SRF to return all the entries in the pg_hba.conf file.
+ */
+Datum
+pg_hba_file_rules(PG_FUNCTION_ARGS)
+{
+	Tuplestorestate *tuple_store;
+	TupleDesc	tupdesc;
+	MemoryContext old_cxt;
+	ReturnSetInfo *rsi;
+
+	/*
+	 * We must use the Materialize mode to be safe against HBA file changes
+	 * while the cursor is open. It's also more efficient than having to look
+	 * up our current position in the parsed list every time.
+	 */
+	rsi = (ReturnSetInfo *) fcinfo->resultinfo;
+
+	/* Check to see if caller supports us returning a tuplestore */
+	if (rsi == NULL || !IsA(rsi, ReturnSetInfo))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("set-valued function called in context that cannot accept a set")));
+	if (!(rsi->allowedModes & SFRM_Materialize))
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("materialize mode required, but it is not allowed in this context")));
+
+	rsi->returnMode = SFRM_Materialize;
+
+	/* Build a tuple descriptor for our result type */
+	if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
+		elog(ERROR, "return type must be a row type");
+
+	/* Build tuplestore to hold the result rows */
+	old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
+
+	tuple_store =
+		tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
+							  false, work_mem);
+	rsi->setDesc = tupdesc;
+	rsi->setResult = tuple_store;
+
+	MemoryContextSwitchTo(old_cxt);
+
+	/* Fill the tuplestore */
+	fill_hba_view(tuple_store, tupdesc);
+
+	PG_RETURN_NULL();
+}
+
+
+/*
+ * Parse one tokenised line from the ident config file and store the result in
+ * an IdentLine structure.
+ *
+ * If parsing fails, log a message and return NULL.
+ *
+ * If ident_user is a regular expression (ie. begins with a slash), it is
+ * compiled and stored in IdentLine structure.
+ *
+ * Note: this function leaks memory when an error occurs.  Caller is expected
+ * to have set a memory context that will be reset if this function returns
+ * NULL.
+ */
+static IdentLine *
+parse_ident_line(TokenizedLine *tok_line)
+{
+	int			line_num = tok_line->line_num;
+	ListCell   *field;
+	List	   *tokens;
+	HbaToken   *token;
+	IdentLine  *parsedline;
+
+	Assert(tok_line->fields != NIL);
+	field = list_head(tok_line->fields);
+
+	parsedline = palloc0(sizeof(IdentLine));
+	parsedline->linenumber = line_num;
+
+	/* Get the map token (must exist) */
+	tokens = lfirst(field);
+	IDENT_MULTI_VALUE(tokens);
+	token = linitial(tokens);
+	parsedline->usermap = pstrdup(token->string);
+
+	/* Get the ident user token */
+	field = lnext(tok_line->fields, field);
+	IDENT_FIELD_ABSENT(field);
+	tokens = lfirst(field);
+	IDENT_MULTI_VALUE(tokens);
+	token = linitial(tokens);
+	parsedline->ident_user = pstrdup(token->string);
+
+	/* Get the PG rolename token */
+	field = lnext(tok_line->fields, field);
+	IDENT_FIELD_ABSENT(field);
+	tokens = lfirst(field);
+	IDENT_MULTI_VALUE(tokens);
+	token = linitial(tokens);
+	parsedline->pg_role = pstrdup(token->string);
+
+	if (parsedline->ident_user[0] == '/')
+	{
+		/*
+		 * When system username starts with a slash, treat it as a regular
+		 * expression. Pre-compile it.
+		 */
+		int			r;
+		pg_wchar   *wstr;
+		int			wlen;
+
+		wstr = palloc((strlen(parsedline->ident_user + 1) + 1) * sizeof(pg_wchar));
+		wlen = pg_mb2wchar_with_len(parsedline->ident_user + 1,
+									wstr, strlen(parsedline->ident_user + 1));
+
+		r = pg_regcomp(&parsedline->re, wstr, wlen, REG_ADVANCED, C_COLLATION_OID);
+		if (r)
+		{
+			char		errstr[100];
+
+			pg_regerror(r, &parsedline->re, errstr, sizeof(errstr));
+			ereport(LOG,
+					(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
+					 errmsg("invalid regular expression \"%s\": %s",
+							parsedline->ident_user + 1, errstr)));
+
+			pfree(wstr);
+			return NULL;
+		}
+		pfree(wstr);
+	}
+
+	return parsedline;
+}
+
+/*
+ *	Process one line from the parsed ident config lines.
+ *
+ *	Compare input parsed ident line to the needed map, pg_role and ident_user.
+ *	*found_p and *error_p are set according to our results.
+ */
+static void
+check_ident_usermap(IdentLine *identLine, const char *usermap_name,
+					const char *pg_role, const char *ident_user,
+					bool case_insensitive, bool *found_p, bool *error_p)
+{
+	*found_p = false;
+	*error_p = false;
+
+	if (strcmp(identLine->usermap, usermap_name) != 0)
+		/* Line does not match the map name we're looking for, so just abort */
+		return;
+
+	/* Match? */
+	if (identLine->ident_user[0] == '/')
+	{
+		/*
+		 * When system username starts with a slash, treat it as a regular
+		 * expression. In this case, we process the system username as a
+		 * regular expression that returns exactly one match. This is replaced
+		 * for \1 in the database username string, if present.
+		 */
+		int			r;
+		regmatch_t	matches[2];
+		pg_wchar   *wstr;
+		int			wlen;
+		char	   *ofs;
+		char	   *regexp_pgrole;
+
+		wstr = palloc((strlen(ident_user) + 1) * sizeof(pg_wchar));
+		wlen = pg_mb2wchar_with_len(ident_user, wstr, strlen(ident_user));
+
+		r = pg_regexec(&identLine->re, wstr, wlen, 0, NULL, 2, matches, 0);
+		if (r)
+		{
+			char		errstr[100];
+
+			if (r != REG_NOMATCH)
+			{
+				/* REG_NOMATCH is not an error, everything else is */
+				pg_regerror(r, &identLine->re, errstr, sizeof(errstr));
+				ereport(LOG,
+						(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
+						 errmsg("regular expression match for \"%s\" failed: %s",
+								identLine->ident_user + 1, errstr)));
+				*error_p = true;
+			}
+
+			pfree(wstr);
+			return;
+		}
+		pfree(wstr);
+
+		if ((ofs = strstr(identLine->pg_role, "\\1")) != NULL)
+		{
+			int			offset;
+
+			/* substitution of the first argument requested */
+			if (matches[1].rm_so < 0)
+			{
+				ereport(LOG,
+						(errcode(ERRCODE_INVALID_REGULAR_EXPRESSION),
+						 errmsg("regular expression \"%s\" has no subexpressions as requested by backreference in \"%s\"",
+								identLine->ident_user + 1, identLine->pg_role)));
+				*error_p = true;
+				return;
+			}
+
+			/*
+			 * length: original length minus length of \1 plus length of match
+			 * plus null terminator
+			 */
+			regexp_pgrole = palloc0(strlen(identLine->pg_role) - 2 + (matches[1].rm_eo - matches[1].rm_so) + 1);
+			offset = ofs - identLine->pg_role;
+			memcpy(regexp_pgrole, identLine->pg_role, offset);
+			memcpy(regexp_pgrole + offset,
+				   ident_user + matches[1].rm_so,
+				   matches[1].rm_eo - matches[1].rm_so);
+			strcat(regexp_pgrole, ofs + 2);
+		}
+		else
+		{
+			/* no substitution, so copy the match */
+			regexp_pgrole = pstrdup(identLine->pg_role);
+		}
+
+		/*
+		 * now check if the username actually matched what the user is trying
+		 * to connect as
+		 */
+		if (case_insensitive)
+		{
+			if (pg_strcasecmp(regexp_pgrole, pg_role) == 0)
+				*found_p = true;
+		}
+		else
+		{
+			if (strcmp(regexp_pgrole, pg_role) == 0)
+				*found_p = true;
+		}
+		pfree(regexp_pgrole);
+
+		return;
+	}
+	else
+	{
+		/* Not regular expression, so make complete match */
+		if (case_insensitive)
+		{
+			if (pg_strcasecmp(identLine->pg_role, pg_role) == 0 &&
+				pg_strcasecmp(identLine->ident_user, ident_user) == 0)
+				*found_p = true;
+		}
+		else
+		{
+			if (strcmp(identLine->pg_role, pg_role) == 0 &&
+				strcmp(identLine->ident_user, ident_user) == 0)
+				*found_p = true;
+		}
+	}
+}
+
+
+/*
+ *	Scan the (pre-parsed) ident usermap file line by line, looking for a match
+ *
+ *	See if the user with ident username "auth_user" is allowed to act
+ *	as Postgres user "pg_role" according to usermap "usermap_name".
+ *
+ *	Special case: Usermap NULL, equivalent to what was previously called
+ *	"sameuser" or "samerole", means don't look in the usermap file.
+ *	That's an implied map wherein "pg_role" must be identical to
+ *	"auth_user" in order to be authorized.
+ *
+ *	Iff authorized, return STATUS_OK, otherwise return STATUS_ERROR.
+ */
+int
+check_usermap(const char *usermap_name,
+			  const char *pg_role,
+			  const char *auth_user,
+			  bool case_insensitive)
+{
+	bool		found_entry = false,
+				error = false;
+
+	if (usermap_name == NULL || usermap_name[0] == '\0')
+	{
+		if (case_insensitive)
+		{
+			if (pg_strcasecmp(pg_role, auth_user) == 0)
+				return STATUS_OK;
+		}
+		else
+		{
+			if (strcmp(pg_role, auth_user) == 0)
+				return STATUS_OK;
+		}
+		ereport(LOG,
+				(errmsg("provided user name (%s) and authenticated user name (%s) do not match",
+						pg_role, auth_user)));
+		return STATUS_ERROR;
+	}
+	else
+	{
+		ListCell   *line_cell;
+
+		foreach(line_cell, parsed_ident_lines)
+		{
+			check_ident_usermap(lfirst(line_cell), usermap_name,
+								pg_role, auth_user, case_insensitive,
+								&found_entry, &error);
+			if (found_entry || error)
+				break;
+		}
+	}
+	if (!found_entry && !error)
+	{
+		ereport(LOG,
+				(errmsg("no match in usermap \"%s\" for user \"%s\" authenticated as \"%s\"",
+						usermap_name, pg_role, auth_user)));
+	}
+	return found_entry ? STATUS_OK : STATUS_ERROR;
+}
+
+
+/*
+ * Read the ident config file and create a List of IdentLine records for
+ * the contents.
+ *
+ * This works the same as load_hba(), but for the user config file.
+ */
+bool
+load_ident(void)
+{
+	FILE	   *file;
+	List	   *ident_lines = NIL;
+	ListCell   *line_cell,
+			   *parsed_line_cell;
+	List	   *new_parsed_lines = NIL;
+	bool		ok = true;
+	MemoryContext linecxt;
+	MemoryContext oldcxt;
+	MemoryContext ident_context;
+	IdentLine  *newline;
+
+	file = AllocateFile(IdentFileName, "r");
+	if (file == NULL)
+	{
+		/* not fatal ... we just won't do any special ident maps */
+		ereport(LOG,
+				(errcode_for_file_access(),
+				 errmsg("could not open usermap file \"%s\": %m",
+						IdentFileName)));
+		return false;
+	}
+
+	linecxt = tokenize_file(IdentFileName, file, &ident_lines, LOG);
+	FreeFile(file);
+
+	/* Now parse all the lines */
+	Assert(PostmasterContext);
+	ident_context = AllocSetContextCreate(PostmasterContext,
+										  "ident parser context",
+										  ALLOCSET_SMALL_SIZES);
+	oldcxt = MemoryContextSwitchTo(ident_context);
+	foreach(line_cell, ident_lines)
+	{
+		TokenizedLine *tok_line = (TokenizedLine *) lfirst(line_cell);
+
+		/* don't parse lines that already have errors */
+		if (tok_line->err_msg != NULL)
+		{
+			ok = false;
+			continue;
+		}
+
+		if ((newline = parse_ident_line(tok_line)) == NULL)
+		{
+			/* Parse error; remember there's trouble */
+			ok = false;
+
+			/*
+			 * Keep parsing the rest of the file so we can report errors on
+			 * more than the first line.  Error has already been logged, no
+			 * need for more chatter here.
+			 */
+			continue;
+		}
+
+		new_parsed_lines = lappend(new_parsed_lines, newline);
+	}
+
+	/* Free tokenizer memory */
+	MemoryContextDelete(linecxt);
+	MemoryContextSwitchTo(oldcxt);
+
+	if (!ok)
+	{
+		/*
+		 * File contained one or more errors, so bail out, first being careful
+		 * to clean up whatever we allocated.  Most stuff will go away via
+		 * MemoryContextDelete, but we have to clean up regexes explicitly.
+		 */
+		foreach(parsed_line_cell, new_parsed_lines)
+		{
+			newline = (IdentLine *) lfirst(parsed_line_cell);
+			if (newline->ident_user[0] == '/')
+				pg_regfree(&newline->re);
+		}
+		MemoryContextDelete(ident_context);
+		return false;
+	}
+
+	/* Loaded new file successfully, replace the one we use */
+	if (parsed_ident_lines != NIL)
+	{
+		foreach(parsed_line_cell, parsed_ident_lines)
+		{
+			newline = (IdentLine *) lfirst(parsed_line_cell);
+			if (newline->ident_user[0] == '/')
+				pg_regfree(&newline->re);
+		}
+	}
+	if (parsed_ident_context != NULL)
+		MemoryContextDelete(parsed_ident_context);
+
+	parsed_ident_context = ident_context;
+	parsed_ident_lines = new_parsed_lines;
+
+	return true;
+}
+
+
+
+/*
+ *	Determine what authentication method should be used when accessing database
+ *	"database" from frontend "raddr", user "user".  Return the method and
+ *	an optional argument (stored in fields of *port), and STATUS_OK.
+ *
+ *	If the file does not contain any entry matching the request, we return
+ *	method = uaImplicitReject.
+ */
+void
+hba_getauthmethod(hbaPort *port)
+{
+	check_hba(port);
+}
+
+
+/*
+ * Return the name of the auth method in use ("gss", "md5", "trust", etc.).
+ *
+ * The return value is statically allocated (see the UserAuthName array) and
+ * should not be freed.
+ */
+const char *
+hba_authname(UserAuth auth_method)
+{
+	/*
+	 * Make sure UserAuthName[] tracks additions to the UserAuth enum
+	 */
+	StaticAssertStmt(lengthof(UserAuthName) == USER_AUTH_LAST + 1,
+					 "UserAuthName[] must match the UserAuth enum");
+
+	return UserAuthName[auth_method];
+}