From 31f5b24e4b336ed37eba108423576cbbf3c4098c Mon Sep 17 00:00:00 2001
From: Magnus Hagander <magnus@hagander.net>
Date: Tue, 28 Oct 2008 12:10:44 +0000
Subject: [PATCH] Remove support for (insecure) crypt authentication.

This breaks compatibility with pre-7.2 versions.
---
 doc/src/sgml/client-auth.sgml       | 35 ++-------------
 doc/src/sgml/protocol.sgml          | 68 -----------------------------
 doc/src/sgml/user-manag.sgml        |  4 +-
 src/backend/libpq/auth.c            |  8 ----
 src/backend/libpq/crypt.c           | 16 -------
 src/backend/libpq/hba.c             |  2 -
 src/backend/postmaster/postmaster.c | 39 +++--------------
 src/include/libpq/hba.h             |  1 -
 src/include/libpq/libpq-be.h        |  1 -
 src/include/libpq/pqcomm.h          |  2 +-
 src/interfaces/libpq/fe-auth.c      | 18 +++-----
 src/interfaces/libpq/fe-connect.c   |  9 ----
 src/interfaces/libpq/libpq-int.h    |  1 -
 13 files changed, 17 insertions(+), 187 deletions(-)

diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml
index 50bf1ce42b..733b6bafd8 100644
--- a/doc/src/sgml/client-auth.sgml
+++ b/doc/src/sgml/client-auth.sgml
@@ -315,24 +315,6 @@ hostnossl  <replaceable>database</replaceable>  <replaceable>user</replaceable>
         </listitem>
        </varlistentry>
 
-       <varlistentry>
-        <term><literal>crypt</></term>
-        <listitem>
-         <note>
-         <para>
-          This option is recommended only for communicating with pre-7.2
-          clients.
-         </para>
-         </note>
-         <para>
-          Require the client to supply a <function>crypt()</>-encrypted
-          password for authentication.
-          <literal>md5</literal> is now recommended over <literal>crypt</>.
-          See <xref linkend="auth-password"> for details.
-         </para>
-        </listitem>
-       </varlistentry>
-
        <varlistentry>
         <term><literal>password</></term>
         <listitem>
@@ -704,9 +686,6 @@ omicron       bryanh            guest1
    <indexterm>
     <primary>MD5</>
    </indexterm>
-   <indexterm>
-    <primary>crypt</>
-   </indexterm>
    <indexterm>
     <primary>password</primary>
     <secondary>authentication</secondary>
@@ -714,21 +693,15 @@ omicron       bryanh            guest1
 
    <para>
     The password-based authentication methods are <literal>md5</>,
-    <literal>crypt</>, and <literal>password</>. These methods operate
+    and <literal>password</>. These methods operate
     similarly except for the way that the password is sent across the
-    connection: respectively, MD5-hashed, crypt-encrypted, and clear-text.
-    A limitation is that the <literal>crypt</> method does not work with
-    passwords that have been encrypted in <structname>pg_authid</structname>.
+    connection: respectively, MD5-hashed and clear-text.
    </para>
 
    <para>
     If you are at all concerned about password
-    <quote>sniffing</> attacks then <literal>md5</> is preferred, with
-    <literal>crypt</> to be used only if you must support pre-7.2
-    clients. Plain <literal>password</> should be avoided especially for
-    connections over the open Internet (unless you use <acronym>SSL</acronym>,
-    <acronym>SSH</>, or another
-    communications security wrapper around the connection).
+    <quote>sniffing</> attacks then <literal>md5</> is preferred.
+    Plain <literal>password</> should always be avoided if possible.
    </para>
 
    <para>
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index 14b5e9ac19..342be652ce 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -295,19 +295,6 @@
       </listitem>
      </varlistentry>
 
-     <varlistentry>
-      <term>AuthenticationCryptPassword</term>
-      <listitem>
-       <para>
-        The frontend must now send a PasswordMessage containing the
-        password encrypted via crypt(3), using the 2-character salt
-        specified in the AuthenticationCryptPassword message.  If
-        this is the correct password, the server responds with an
-        AuthenticationOk, otherwise it responds with an ErrorResponse.
-       </para>
-      </listitem>
-     </varlistentry>
-
      <varlistentry>
       <term>AuthenticationMD5Password</term>
       <listitem>
@@ -1531,61 +1518,6 @@ AuthenticationCleartextPassword (B)
 </varlistentry>
 
 
-<varlistentry>
-<term>
-AuthenticationCryptPassword (B)
-</term>
-<listitem>
-<para>
-
-<variablelist>
-<varlistentry>
-<term>
-        Byte1('R')
-</term>
-<listitem>
-<para>
-                Identifies the message as an authentication request.
-</para>
-</listitem>
-</varlistentry>
-<varlistentry>
-<term>
-        Int32(10)
-</term>
-<listitem>
-<para>
-                Length of message contents in bytes, including self.
-</para>
-</listitem>
-</varlistentry>
-<varlistentry>
-<term>
-        Int32(4)
-</term>
-<listitem>
-<para>
-                Specifies that a crypt()-encrypted password is required.
-</para>
-</listitem>
-</varlistentry>
-<varlistentry>
-<term>
-        Byte2
-</term>
-<listitem>
-<para>
-                The salt to use when encrypting the password.
-</para>
-</listitem>
-</varlistentry>
-</variablelist>
-
-</para>
-</listitem>
-</varlistentry>
-
-
 <varlistentry>
 <term>
 AuthenticationMD5Password (B)
diff --git a/doc/src/sgml/user-manag.sgml b/doc/src/sgml/user-manag.sgml
index 357e00c352..594e574a05 100644
--- a/doc/src/sgml/user-manag.sgml
+++ b/doc/src/sgml/user-manag.sgml
@@ -215,8 +215,8 @@ CREATE USER <replaceable>name</replaceable>;
        <para>
         A password is only significant if the client authentication
         method requires the user to supply a password when connecting
-        to the database. The <option>password</>,
-        <option>md5</>, and <option>crypt</> authentication methods
+        to the database. The <option>password</> and
+        <option>md5</> authentication methods
         make use of passwords. Database passwords are separate from
         operating system passwords. Specify a password upon role
         creation with <literal>CREATE ROLE
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 85c16781eb..3e21a11c8f 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -230,7 +230,6 @@ auth_failed(Port *port, int status)
 			errstr = gettext_noop("Ident authentication failed for user \"%s\"");
 			break;
 		case uaMD5:
-		case uaCrypt:
 		case uaPassword:
 			errstr = gettext_noop("password authentication failed for user \"%s\"");
 			break;
@@ -373,11 +372,6 @@ ClientAuthentication(Port *port)
 			status = recv_and_check_password_packet(port);
 			break;
 
-		case uaCrypt:
-			sendAuthRequest(port, AUTH_REQ_CRYPT);
-			status = recv_and_check_password_packet(port);
-			break;
-
 		case uaPassword:
 			sendAuthRequest(port, AUTH_REQ_PASSWORD);
 			status = recv_and_check_password_packet(port);
@@ -426,8 +420,6 @@ sendAuthRequest(Port *port, AuthRequest areq)
 	/* Add the salt for encrypted passwords. */
 	if (areq == AUTH_REQ_MD5)
 		pq_sendbytes(&buf, port->md5Salt, 4);
-	else if (areq == AUTH_REQ_CRYPT)
-		pq_sendbytes(&buf, port->cryptSalt, 2);
 
 #if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
 
diff --git a/src/backend/libpq/crypt.c b/src/backend/libpq/crypt.c
index 48b39ddd03..9f0e911e44 100644
--- a/src/backend/libpq/crypt.c
+++ b/src/backend/libpq/crypt.c
@@ -53,14 +53,6 @@ md5_crypt_verify(const Port *port, const char *role, char *client_pass)
 	if (shadow_pass == NULL || *shadow_pass == '\0')
 		return STATUS_ERROR;
 
-	/* We can't do crypt with MD5 passwords */
-	if (isMD5(shadow_pass) && port->hba->auth_method == uaCrypt)
-	{
-		ereport(LOG,
-				(errmsg("cannot use authentication method \"crypt\" because password is MD5-encrypted")));
-		return STATUS_ERROR;
-	}
-
 	/*
 	 * Compare with the encrypted or plain password depending on the
 	 * authentication method being used for this connection.
@@ -106,14 +98,6 @@ md5_crypt_verify(const Port *port, const char *role, char *client_pass)
 				pfree(crypt_pwd2);
 			}
 			break;
-		case uaCrypt:
-			{
-				char		salt[3];
-
-				strlcpy(salt, port->cryptSalt, sizeof(salt));
-				crypt_pwd = crypt(shadow_pass, salt);
-				break;
-			}
 		default:
 			if (isMD5(shadow_pass))
 			{
diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index 85b3f77de5..bf12e21ab7 100644
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -847,8 +847,6 @@ parse_hba_line(List *line, int line_num, HbaLine *parsedline)
 		parsedline->auth_method = uaReject;
 	else if (strcmp(token, "md5") == 0)
 		parsedline->auth_method = uaMD5;
-	else if (strcmp(token, "crypt") == 0)
-		parsedline->auth_method = uaCrypt;
 	else if (strcmp(token, "pam") == 0)
 #ifdef USE_PAM
 		parsedline->auth_method = uaPAM;
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index aaaab64a86..6dcc964712 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -323,7 +323,7 @@ static int	initMasks(fd_set *rmask);
 static void report_fork_failure_to_client(Port *port, int errnum);
 static enum CAC_state canAcceptConnections(void);
 static long PostmasterRandom(void);
-static void RandomSalt(char *cryptSalt, char *md5Salt);
+static void RandomSalt(char *md5Salt);
 static void signal_child(pid_t pid, int signal);
 static void SignalSomeChildren(int signal, bool only_autovac);
 
@@ -1808,7 +1808,7 @@ ConnCreate(int serverFd)
 		 * fork, not after.  Else the postmaster's random sequence won't get
 		 * advanced, and all backends would end up using the same salt...
 		 */
-		RandomSalt(port->cryptSalt, port->md5Salt);
+		RandomSalt(port->md5Salt);
 	}
 
 	/*
@@ -3910,49 +3910,20 @@ dummy_handler(SIGNAL_ARGS)
 {
 }
 
-
-/*
- * CharRemap: given an int in range 0..61, produce textual encoding of it
- * per crypt(3) conventions.
- */
-static char
-CharRemap(long ch)
-{
-	if (ch < 0)
-		ch = -ch;
-	ch = ch % 62;
-
-	if (ch < 26)
-		return 'A' + ch;
-
-	ch -= 26;
-	if (ch < 26)
-		return 'a' + ch;
-
-	ch -= 26;
-	return '0' + ch;
-}
-
 /*
  * RandomSalt
  */
 static void
-RandomSalt(char *cryptSalt, char *md5Salt)
+RandomSalt(char *md5Salt)
 {
-	long		rand = PostmasterRandom();
-
-	cryptSalt[0] = CharRemap(rand % 62);
-	cryptSalt[1] = CharRemap(rand / 62);
+	long		rand;
 
 	/*
-	 * It's okay to reuse the first random value for one of the MD5 salt
-	 * bytes, since only one of the two salts will be sent to the client.
-	 * After that we need to compute more random bits.
-	 *
 	 * We use % 255, sacrificing one possible byte value, so as to ensure that
 	 * all bits of the random() value participate in the result. While at it,
 	 * add one to avoid generating any null bytes.
 	 */
+	rand = PostmasterRandom();
 	md5Salt[0] = (rand % 255) + 1;
 	rand = PostmasterRandom();
 	md5Salt[1] = (rand % 255) + 1;
diff --git a/src/include/libpq/hba.h b/src/include/libpq/hba.h
index 21467a1cc3..d9d5cd1950 100644
--- a/src/include/libpq/hba.h
+++ b/src/include/libpq/hba.h
@@ -22,7 +22,6 @@ typedef enum UserAuth
 	uaTrust,
 	uaIdent,
 	uaPassword,
-	uaCrypt,
 	uaMD5,
 	uaGSS,
 	uaSSPI,
diff --git a/src/include/libpq/libpq-be.h b/src/include/libpq/libpq-be.h
index 306bc5d6c9..886ce8feaf 100644
--- a/src/include/libpq/libpq-be.h
+++ b/src/include/libpq/libpq-be.h
@@ -123,7 +123,6 @@ typedef struct Port
 	 */
 	HbaLine	   *hba;
 	char		md5Salt[4];		/* Password salt */
-	char		cryptSalt[2];	/* Password salt */
 
 	/*
 	 * Information that really has no business at all being in struct Port,
diff --git a/src/include/libpq/pqcomm.h b/src/include/libpq/pqcomm.h
index 2a0f9339b6..7ba6612235 100644
--- a/src/include/libpq/pqcomm.h
+++ b/src/include/libpq/pqcomm.h
@@ -153,7 +153,7 @@ extern bool Db_user_namespace;
 #define AUTH_REQ_KRB4		1	/* Kerberos V4. Not supported any more. */
 #define AUTH_REQ_KRB5		2	/* Kerberos V5 */
 #define AUTH_REQ_PASSWORD	3	/* Password */
-#define AUTH_REQ_CRYPT		4	/* crypt 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() */
diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index 490ca1bb3b..a2e7f49c61 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -40,10 +40,6 @@
 #include <pwd.h>
 #endif
 
-#ifdef HAVE_CRYPT_H
-#include <crypt.h>
-#endif
-
 #include "libpq-fe.h"
 #include "fe-auth.h"
 #include "libpq/md5.h"
@@ -787,14 +783,6 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 				}
 				break;
 			}
-		case AUTH_REQ_CRYPT:
-			{
-				char		salt[3];
-
-				strlcpy(salt, conn->cryptSalt, sizeof(salt));
-				crypt_pwd = crypt(password, salt);
-				break;
-			}
 		case AUTH_REQ_PASSWORD:
 			/* discard const so we can assign it */
 			crypt_pwd = (char *) password;
@@ -938,8 +926,12 @@ pg_fe_sendauth(AuthRequest areq, PGconn *conn)
 #endif
 
 
-		case AUTH_REQ_MD5:
 		case AUTH_REQ_CRYPT:
+			printfPQExpBuffer(&conn->errorMessage,
+				 libpq_gettext("Crypt authentication not supported\n"));
+			return STATUS_ERROR;
+
+		case AUTH_REQ_MD5:
 		case AUTH_REQ_PASSWORD:
 			conn->password_needed = true;
 			if (conn->pgpass == NULL || conn->pgpass[0] == '\0')
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 17642d8b59..4c4615703a 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -1674,15 +1674,6 @@ keep_going:						/* We will come back to here until there is
 						return PGRES_POLLING_READING;
 					}
 				}
-				if (areq == AUTH_REQ_CRYPT)
-				{
-					if (pqGetnchar(conn->cryptSalt,
-								   sizeof(conn->cryptSalt), conn))
-					{
-						/* We'll come back when there are more data */
-						return PGRES_POLLING_READING;
-					}
-				}
 #if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
 
 				/*
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index 272d3b1dc7..1007849daa 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -340,7 +340,6 @@ struct pg_conn
 	int			be_pid;			/* PID of backend --- needed for cancels */
 	int			be_key;			/* key of backend --- needed for cancels */
 	char		md5Salt[4];		/* password salt received from backend */
-	char		cryptSalt[2];	/* password salt received from backend */
 	pgParameterStatus *pstatus; /* ParameterStatus data */
 	int			client_encoding;	/* encoding id */
 	bool		std_strings;	/* standard_conforming_strings */
-- 
2.39.5