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Modify libpq's string-escaping routines to be aware of encoding considerations

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and standard_conforming_strings.  The encoding changes are needed for proper
escaping in multibyte encodings, as per the SQL-injection vulnerabilities
noted in CVE-2006-2313 and CVE-2006-2314.  Concurrent fixes are being applied
to the server to ensure that it rejects queries that may have been corrupted
by attempted SQL injection, but this merely guarantees that unpatched clients
will fail rather than allow injection.  An actual fix requires changing the
client-side code.  While at it we have also fixed these routines to understand
about standard_conforming_strings, so that the upcoming changeover to SQL-spec
string syntax can be somewhat transparent to client code.

Since the existing API of PQescapeString and PQescapeBytea provides no way to
inform them which settings are in use, these functions are now deprecated in
favor of new functions PQescapeStringConn and PQescapeByteaConn.  The new
functions take the PGconn to which the string will be sent as an additional
parameter, and look inside the connection structure to determine what to do.
So as to provide some functionality for clients using the old functions,
libpq stores the latest encoding and standard_conforming_strings values
received from the backend in static variables, and the old functions consult
these variables.  This will work reliably in clients using only one Postgres
connection at a time, or even multiple connections if they all use the same
encoding and string syntax settings; which should cover many practical
scenarios.

Clients that use homebrew escaping methods, such as PHP's addslashes()
function or even hardwired regexp substitution, will require extra effort
to fix :-(.  It is strongly recommended that such code be replaced by use of
PQescapeStringConn/PQescapeByteaConn if at all feasible.
This commit is contained in:
Tom Lane 2006-05-21 20:20:48 +00:00
parent 16e77740ea
commit e6f43f7786
6 changed files with 374 additions and 142 deletions
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263
doc/src/sgml/libpq.sgml
View File

@ -1,5 +1,5 @@
<!-- <!--
$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.98.2.5 2003/01/30 19:50:07 tgl Exp $ $Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.98.2.6 2006/05/21 20:20:48 tgl Exp $
--> -->
<chapter id="libpq"> <chapter id="libpq">
@ -880,114 +880,233 @@ as with a <structname>PGresult</structname> returned by <application>libpq</appl
</sect2> </sect2>
<sect2 id="libpq-exec-escape-string"> <sect2 id="libpq-exec-escape-string">
<title>Escaping strings for inclusion in SQL queries</title> <title>Escaping Strings for Inclusion in SQL Commands</title>
<indexterm zone="libpq-exec-escape-string"><primary>PQescapeStringConn</></>
<indexterm zone="libpq-exec-escape-string"><primary>PQescapeString</></>
<indexterm zone="libpq-exec-escape-string"><primary>escaping strings</></> <indexterm zone="libpq-exec-escape-string"><primary>escaping strings</></>
<para> <para>
<function>PQescapeString</function> <function>PQescapeStringConn</function> escapes a string for use within an SQL
Escapes a string for use within an SQL query. command. This is useful when inserting data values as literal constants
in SQL commands. Certain characters (such as quotes and backslashes) must
be escaped to prevent them from being interpreted specially by the SQL parser.
<function>PQescapeStringConn</> performs this operation.
</para>
<tip>
<para>
It is especially important to do proper escaping when handling strings that
were received from an untrustworthy source. Otherwise there is a security
risk: you are vulnerable to <quote>SQL injection</> attacks wherein unwanted
SQL commands are fed to your database.
</para>
</tip>
<para>
<synopsis>
size_t PQescapeStringConn (PGconn *conn,
char *to, const char *from, size_t length,
int *error);
</synopsis>
</para>
<para>
<function>PQescapeStringConn</> writes an escaped
version of the <parameter>from</> string to the <parameter>to</>
buffer, escaping special characters so that they cannot cause any
harm, and adding a terminating zero byte. The single quotes that
must surround <productname>PostgreSQL</> string literals are not
included in the result string; they should be provided in the SQL
command that the result is inserted into.
The parameter <parameter>from</> points to the first character of the string
that is to be escaped, and the <parameter>length</> parameter gives the
number of bytes in this string. A terminating zero byte is not
required, and should not be counted in <parameter>length</>. (If
a terminating zero byte is found before <parameter>length</> bytes are
processed, <function>PQescapeStringConn</> stops at the zero; the behavior
is thus rather like <function>strncpy</>.)
<parameter>to</> shall point to a
buffer that is able to hold at least one more byte than twice
the value of <parameter>length</>, otherwise the behavior is
undefined.
Behavior is likewise undefined if the <parameter>to</> and <parameter>from</>
strings overlap.
</para>
<para>
If the <parameter>error</> parameter is not NULL, then <literal>*error</>
is set to zero on success, nonzero on error. Presently the only possible
error conditions involve invalid multibyte encoding in the source string.
The output string is still generated on error, but it can be expected that
the server will reject it as malformed. On error, a suitable message is
stored in the <parameter>conn</> object, whether or not <parameter>error</>
is NULL.
</para>
<para>
<function>PQescapeStringConn</> returns the number of bytes written
to <parameter>to</>, not including the terminating zero byte.
</para>
<para>
<synopsis> <synopsis>
size_t PQescapeString (char *to, const char *from, size_t length); size_t PQescapeString (char *to, const char *from, size_t length);
</synopsis> </synopsis>
If you want to include strings that have been received </para>
from a source that is not trustworthy (for example, because a random user
entered them), you cannot directly include them in SQL <para>
queries for security reasons. Instead, you have to quote special <function>PQescapeString</> is an older, deprecated version of
characters that are otherwise interpreted by the SQL parser. <function>PQescapeStringConn</>; the difference is that it does not
take <parameter>conn</> or <parameter>error</> parameters. Because of this,
it cannot adjust its behavior depending on the connection properties (such as
character encoding) and therefore <emphasis>it may give the wrong results</>.
Also, it has no way to report error conditions.
</para> </para>
<para> <para>
<function>PQescapeString</> performs this operation. The <function>PQescapeString</> can be used safely in single-threaded client
<parameter>from</> points to the first character of the string that programs that work with only one <productname>PostgreSQL</> connection at
is to be escaped, and the <parameter>length</> parameter counts the a time (in this case it can find out what it needs to know <quote>behind the
number of characters in this string (a terminating zero byte is scenes</>). In other contexts it is a security hazard and should be avoided
neither necessary nor counted). <parameter>to</> shall point to a in favor of <function>PQescapeStringConn</>.
buffer that is able to hold at least one more character than twice
the value of <parameter>length</>, otherwise the behavior is
undefined. A call to <function>PQescapeString</> writes an escaped
version of the <parameter>from</> string to the <parameter>to</>
buffer, replacing special characters so that they cannot cause any
harm, and adding a terminating zero byte. The single quotes that
must surround <productname>PostgreSQL</> string literals are not part of the result
string.
</para>
<para>
<function>PQescapeString</> returns the number of characters written
to <parameter>to</>, not including the terminating zero byte.
Behavior is undefined when the <parameter>to</> and <parameter>from</>
strings overlap.
</para> </para>
</sect2> </sect2>
<sect2 id="libpq-exec-escape-bytea"> <sect2 id="libpq-exec-escape-bytea">
<title>Escaping binary strings for inclusion in SQL queries</title> <title>Escaping Binary Strings for Inclusion in SQL Commands</title>
<indexterm zone="libpq-exec-escape-bytea"> <indexterm zone="libpq-exec-escape-bytea">
<primary>escaping binary strings</primary> <primary>bytea</>
<secondary sortas="libpq">in libpq</>
</indexterm> </indexterm>
<variablelist>
<varlistentry>
<term><function>PQescapeByteaConn</function><indexterm><primary>PQescapeByteaConn</></></term>
<listitem>
<para> <para>
<function>PQescapeBytea</function> Escapes binary data for use within an SQL command with the type
Escapes a binary string (<type>bytea</type> type) for use within an SQL query. <type>bytea</type>.
<synopsis>
unsigned char *PQescapeByteaConn(PGconn *conn,
const unsigned char *from,
size_t from_length,
size_t *to_length);
</synopsis>
</para>
<para>
Certain byte values <emphasis>must</emphasis> be escaped (but all
byte values <emphasis>can</emphasis> be escaped) when used as part
of a <type>bytea</type> literal in an <acronym>SQL</acronym>
statement. In general, to escape a byte, it is converted into the
three digit octal number equal to the octet value, and preceded by
one or two backslashes. The single quote (<literal>'</>) and backslash
(<literal>\</>) characters have special alternative escape
sequences. <function>PQescapeByteaConn</function> performs this
operation, escaping only the minimally required bytes.
</para>
<para>
The <parameter>from</parameter> parameter points to the first
byte of the string that is to be escaped, and the
<parameter>from_length</parameter> parameter gives the number of
bytes in this binary string. (A terminating zero byte is
neither necessary nor counted.) The <parameter>to_length</parameter>
parameter points to a variable that will hold the resultant
escaped string length. This result string length includes the terminating
zero byte of the result.
</para>
<para>
<function>PQescapeByteaConn</> returns an escaped version of the
<parameter>from</parameter> parameter binary string in memory
allocated with <function>malloc()</>. This memory must be freed using
<function>free()</> when the result is no longer needed. The
return string has all special characters replaced so that they can
be properly processed by the <productname>PostgreSQL</productname>
string literal parser, and the <type>bytea</type> input function. A
terminating zero byte is also added. The single quotes that must
surround <productname>PostgreSQL</productname> string literals are
not part of the result string.
</para>
<para>
On error, a NULL pointer is returned, and a suitable error message
is stored in the <parameter>conn</> object. Currently, the only
possible error is insufficient memory for the result string.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><function>PQescapeBytea</function><indexterm><primary>PQescapeBytea</></></term>
<listitem>
<para>
<function>PQescapeBytea</> is an older, deprecated version of
<function>PQescapeByteaConn</>.
<synopsis> <synopsis>
unsigned char *PQescapeBytea(unsigned char *from, unsigned char *PQescapeBytea(unsigned char *from,
size_t from_length, size_t from_length,
size_t *to_length); size_t *to_length);
</synopsis> </synopsis>
Certain <acronym>ASCII</acronym> characters <emphasis>must</emphasis>
be escaped (but all characters <emphasis>may</emphasis> be escaped)
when used as part of a <type>bytea</type>
string literal in an <acronym>SQL</acronym> statement. In general, to
escape a character, it is converted into the three digit octal number
equal to the decimal <acronym>ASCII</acronym> value, and preceded by
two backslashes. The single quote (') and backslash (\) characters have
special alternate escape sequences. See the <citetitle>User's Guide</citetitle>
for more information. <function>PQescapeBytea
</function> performs this operation, escaping only the minimally
required characters.
</para> </para>
<para> <para>
The <parameter>from</parameter> parameter points to the first The only difference from <function>PQescapeByteaConn</> is that
character of the string that is to be escaped, and the <function>PQescapeBytea</> does not
<parameter>from_length</parameter> parameter reflects the number of take a <structname>PGconn</> parameter. Because of this, it cannot adjust
characters in this binary string (a terminating zero byte is its behavior depending on the connection properties
neither necessary nor counted). The <parameter>to_length</parameter> and therefore <emphasis>it may give the wrong results</>. Also, it
parameter shall point to a buffer suitable to hold the resultant has no way to return an error message on failure.
escaped string length. The result string length includes the terminating
zero byte of the result.
</para> </para>
<para> <para>
<function>PQescapeBytea</> returns an escaped version of the <function>PQescapeBytea</> can be used safely in single-threaded client
<parameter>from</parameter> parameter binary string, to a caller-provided programs that work with only one <productname>PostgreSQL</> connection at
buffer. The return string has all special characters replaced a time (in this case it can find out what it needs to know <quote>behind the
so that they can be properly processed by the PostgreSQL string literal scenes</>). In other contexts it is a security hazard and should be
parser, and the <type>bytea</type> input function. A terminating zero avoided in favor of <function>PQescapeByteaConn</>.
byte is also added. The single quotes that must surround
PostgreSQL string literals are not part of the result string.
</para> </para>
</listitem>
</varlistentry>
<varlistentry>
<term><function>PQunescapeBytea</function><indexterm><primary>PQunescapeBytea</></></term>
<listitem>
<para> <para>
<function>PQunescapeBytea</function> Converts a string representation of binary data into binary
Converts an escaped string representation of binary data into binary data --- the reverse of <function>PQescapeBytea</function>.
data - the reverse of <function>PQescapeBytea</function>. This is needed when retrieving <type>bytea</type> data in text format,
but not when retrieving it in binary format.
<synopsis> <synopsis>
unsigned char *PQunescapeBytea(unsigned char *from, size_t *to_length); unsigned char *PQunescapeBytea(unsigned char *from, size_t *to_length);
</synopsis> </synopsis>
The <parameter>from</parameter> parameter points to an escaped string
such as might be returned by <function>PQgetvalue</function> of a
<type>BYTEA</type> column. <function>PQunescapeBytea</function> converts
this string representation into its binary representation, filling the supplied buffer.
It returns a pointer to the buffer which is NULL on error, and the size
of the buffer in <parameter>to_length</parameter>. The pointer may
subsequently be used as an argument to the function
<function>free(3)</function>.
</para> </para>
</sect2> <para>
The <parameter>from</parameter> parameter points to a string
such as might be returned by <function>PQgetvalue</function> when applied
to a <type>bytea</type> column. <function>PQunescapeBytea</function>
converts this string representation into its binary representation.
It returns a pointer to a buffer allocated with
<function>malloc()</function>, or null on error, and puts the size of
the buffer in <parameter>to_length</parameter>. The result must be
freed using <function>free()</> when it is no longer needed.
</para>
<para>
This conversion is not exactly the inverse of
<function>PQescapeBytea</function>, because the string is not expected
to be <quote>escaped</> when received from <function>PQgetvalue</function>.
In particular this means there is no need for string quoting considerations,
and so no need for a <structname>PGconn</> parameter.
</para>
</listitem>
</varlistentry>
</variablelist>
</sect2>
<sect2 id="libpq-exec-select-info"> <sect2 id="libpq-exec-select-info">
<title>Retrieving SELECT Result Information</title> <title>Retrieving SELECT Result Information</title>

6
src/interfaces/libpq/fe-connect.c
View File

@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.213.2.5 2005/07/14 14:07:50 tgl Exp $ * $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.213.2.6 2006/05/21 20:20:48 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -1642,6 +1642,7 @@ PQsetenvPoll(PGconn *conn)
goto error_return; goto error_return;
} }
conn->client_encoding = encoding; conn->client_encoding = encoding;
PQ_static_client_encoding = conn->client_encoding;
/* Move on to setting the environment options */ /* Move on to setting the environment options */
conn->setenv_state = SETENV_STATE_OPTION_SEND; conn->setenv_state = SETENV_STATE_OPTION_SEND;
@ -1668,6 +1669,7 @@ PQsetenvPoll(PGconn *conn)
conn->client_encoding = PG_SQL_ASCII; conn->client_encoding = PG_SQL_ASCII;
else else
conn->client_encoding = pg_char_to_encoding(encoding); conn->client_encoding = pg_char_to_encoding(encoding);
PQ_static_client_encoding = conn->client_encoding;
} }
else if (PQresultStatus(res) != PGRES_COMMAND_OK) else if (PQresultStatus(res) != PGRES_COMMAND_OK)
{ {
@ -1857,6 +1859,7 @@ makeEmptyPGconn(void)
conn->status = CONNECTION_BAD; conn->status = CONNECTION_BAD;
conn->asyncStatus = PGASYNC_IDLE; conn->asyncStatus = PGASYNC_IDLE;
conn->setenv_state = SETENV_STATE_IDLE; conn->setenv_state = SETENV_STATE_IDLE;
conn->client_encoding = PG_SQL_ASCII;
conn->notifyList = DLNewList(); conn->notifyList = DLNewList();
conn->sock = -1; conn->sock = -1;
#ifdef USE_SSL #ifdef USE_SSL
@ -2763,6 +2766,7 @@ PQsetClientEncoding(PGconn *conn, const char *encoding)
{ {
/* change libpq internal encoding */ /* change libpq internal encoding */
conn->client_encoding = pg_char_to_encoding(encoding); conn->client_encoding = pg_char_to_encoding(encoding);
PQ_static_client_encoding = conn->client_encoding;
status = 0; /* everything is ok */ status = 0; /* everything is ok */
} }
PQclear(res); PQclear(res);

204
src/interfaces/libpq/fe-exec.c
View File

@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-exec.c,v 1.122.2.2 2006/05/21 19:56:41 momjian Exp $ * $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-exec.c,v 1.122.2.3 2006/05/21 20:20:48 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -20,6 +20,7 @@
#include "libpq-fe.h" #include "libpq-fe.h"
#include "libpq-int.h" #include "libpq-int.h"
#include "mb/pg_wchar.h"
#ifdef WIN32 #ifdef WIN32
#include "win32.h" #include "win32.h"
@ -39,6 +40,12 @@ char *const pgresStatus[] = {
"PGRES_FATAL_ERROR" "PGRES_FATAL_ERROR"
}; };
/*
* static state needed by PQescapeString and PQescapeBytea; initialize to
* values that result in backward-compatible behavior
*/
int PQ_static_client_encoding = PG_SQL_ASCII;
static bool static_std_strings = false;
/* Note: DONOTICE macro will work if applied to either PGconn or PGresult */ /* Note: DONOTICE macro will work if applied to either PGconn or PGresult */
#define DONOTICE(conn,message) \ #define DONOTICE(conn,message) \
@ -59,45 +66,80 @@ static int getNotice(PGconn *conn);
/* --------------- /* ---------------
* Escaping arbitrary strings to get valid SQL strings/identifiers. * Escaping arbitrary strings to get valid SQL strings/identifiers.
* *
* Replaces "\\" with "\\\\" and "'" with "''". * Replaces "'" with "''", and if not std_strings, replaces "\" with "\\".
* length is the length of the buffer pointed to by * length is the length of the buffer pointed to by
* from. The buffer at to must be at least 2*length + 1 characters * from. The buffer at to must be at least 2*length + 1 characters
* long. A terminating NUL character is written. * long. A terminating NUL character is written.
* --------------- * ---------------
*/ */
static size_t
size_t PQescapeStringInternal(PGconn *conn,
PQescapeString(char *to, const char *from, size_t length) char *to, const char *from, size_t length,
int *error,
int encoding, bool std_strings)
{ {
const char *source = from; const char *source = from;
char *target = to; char *target = to;
unsigned int remaining = length; size_t remaining = length;
while (remaining > 0) if (error)
*error = 0;
while (remaining > 0 && *source != '\0')
{ {
switch (*source) char c = *source;
int len;
int i;
/* Fast path for plain ASCII */
if (!IS_HIGHBIT_SET(c))
{ {
case '\\': /* Apply quoting if needed */
*target = '\\'; if (c == '\'' ||
target++; (c == '\\' && !std_strings))
*target = '\\'; *target++ = c;
/* target and remaining are updated below. */ /* Copy the character */
break; *target++ = c;
case '\'':
*target = '\'';
target++;
*target = '\'';
/* target and remaining are updated below. */
break;
default:
*target = *source;
/* target and remaining are updated below. */
}
source++; source++;
target++;
remaining--; remaining--;
continue;
}
/* Slow path for possible multibyte characters */
len = pg_encoding_mblen(encoding, source);
/* Copy the character */
for (i = 0; i < len; i++)
{
if (remaining == 0 || *source == '\0')
break;
*target++ = *source++;
remaining--;
}
/*
* If we hit premature end of string (ie, incomplete multibyte
* character), try to pad out to the correct length with spaces.
* We may not be able to pad completely, but we will always be able
* to insert at least one pad space (since we'd not have quoted a
* multibyte character). This should be enough to make a string that
* the server will error out on.
*/
if (i < len)
{
if (error)
*error = 1;
if (conn)
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("incomplete multibyte character\n"));
for (; i < len; i++)
{
if (((size_t) (target - to)) / 2 >= length)
break;
*target++ = ' ';
}
break;
}
} }
/* Write the terminating NUL character. */ /* Write the terminating NUL character. */
@ -106,72 +148,109 @@ PQescapeString(char *to, const char *from, size_t length)
return target - to; return target - to;
} }
size_t
PQescapeStringConn(PGconn *conn,
char *to, const char *from, size_t length,
int *error)
{
if (!conn)
{
/* force empty-string result */
*to = '\0';
if (error)
*error = 1;
return 0;
}
return PQescapeStringInternal(conn, to, from, length, error,
conn->client_encoding,
static_std_strings);
}
size_t
PQescapeString(char *to, const char *from, size_t length)
{
return PQescapeStringInternal(NULL, to, from, length, NULL,
PQ_static_client_encoding,
static_std_strings);
}
/* /*
* PQescapeBytea - converts from binary string to the * PQescapeBytea - converts from binary string to the
* minimal encoding necessary to include the string in an SQL * minimal encoding necessary to include the string in an SQL
* INSERT statement with a bytea type column as the target. * INSERT statement with a bytea type column as the target.
* *
* The following transformations are applied * The following transformations are applied
* '\0' == ASCII 0 == \\000 * '\0' == ASCII 0 == \000
* '\'' == ASCII 39 == \' * '\'' == ASCII 39 == ''
* '\\' == ASCII 92 == \\\\ * '\\' == ASCII 92 == \\
* anything < 0x20, or > 0x7e ---> \\ooo * anything < 0x20, or > 0x7e ---> \ooo
* (where ooo is an octal expression) * (where ooo is an octal expression)
* If not std_strings, all backslashes sent to the output are doubled.
*/ */
unsigned char * static unsigned char *
PQescapeBytea(unsigned char *bintext, size_t binlen, size_t *bytealen) PQescapeByteaInternal(PGconn *conn,
const unsigned char *from, size_t from_length,
size_t *to_length, bool std_strings)
{ {
unsigned char *vp; const unsigned char *vp;
unsigned char *rp; unsigned char *rp;
unsigned char *result; unsigned char *result;
size_t i; size_t i;
size_t len; size_t len;
size_t bslash_len = (std_strings ? 1 : 2);
/* /*
* empty string has 1 char ('\0') * empty string has 1 char ('\0')
*/ */
len = 1; len = 1;
vp = bintext; vp = from;
for (i = binlen; i > 0; i--, vp++) for (i = from_length; i > 0; i--, vp++)
{ {
if (*vp < 0x20 || *vp > 0x7e) if (*vp < 0x20 || *vp > 0x7e)
len += 5; /* '5' is for '\\ooo' */ len += bslash_len + 3;
else if (*vp == '\'') else if (*vp == '\'')
len += 2; len += 2;
else if (*vp == '\\') else if (*vp == '\\')
len += 4; len += bslash_len + bslash_len;
else else
len++; len++;
} }
*to_length = len;
rp = result = (unsigned char *) malloc(len); rp = result = (unsigned char *) malloc(len);
if (rp == NULL) if (rp == NULL)
{
if (conn)
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("out of memory\n"));
return NULL; return NULL;
}
vp = bintext; vp = from;
*bytealen = len; for (i = from_length; i > 0; i--, vp++)
for (i = binlen; i > 0; i--, vp++)
{ {
if (*vp < 0x20 || *vp > 0x7e) if (*vp < 0x20 || *vp > 0x7e)
{ {
(void) sprintf(rp, "\\\\%03o", *vp); if (!std_strings)
rp += 5; *rp++ = '\\';
(void) sprintf((char *) rp, "\\%03o", *vp);
rp += 4;
} }
else if (*vp == '\'') else if (*vp == '\'')
{ {
rp[0] = '\''; *rp++ = '\'';
rp[1] = '\''; *rp++ = '\'';
rp += 2;
} }
else if (*vp == '\\') else if (*vp == '\\')
{ {
rp[0] = '\\'; if (!std_strings)
rp[1] = '\\'; {
rp[2] = '\\'; *rp++ = '\\';
rp[3] = '\\'; *rp++ = '\\';
rp += 4; }
*rp++ = '\\';
*rp++ = '\\';
} }
else else
*rp++ = *vp; *rp++ = *vp;
@ -181,12 +260,31 @@ PQescapeBytea(unsigned char *bintext, size_t binlen, size_t *bytealen)
return result; return result;
} }
unsigned char *
PQescapeByteaConn(PGconn *conn,
const unsigned char *from, size_t from_length,
size_t *to_length)
{
if (!conn)
return NULL;
return PQescapeByteaInternal(conn, from, from_length, to_length,
static_std_strings);
}
unsigned char *
PQescapeBytea(unsigned char *from, size_t from_length, size_t *to_length)
{
return PQescapeByteaInternal(NULL, from, from_length, to_length,
static_std_strings);
}
/* /*
* PQunescapeBytea - converts the null terminated string representation * PQunescapeBytea - converts the null terminated string representation
* of a bytea, strtext, into binary, filling a buffer. It returns a * of a bytea, strtext, into binary, filling a buffer. It returns a
* pointer to the buffer which is NULL on error, and the size of the * pointer to the buffer which is NULL on error, and the size of the
* buffer in retbuflen. The pointer may subsequently be used as an * buffer in retbuflen. The pointer may subsequently be used as an
* argument to the function free(3). It is the reverse of PQescapeBytea. * argument to the function PQfreemem.
* *
* The following transformations are reversed: * The following transformations are reversed:
* '\0' == ASCII 0 == \000 * '\0' == ASCII 0 == \000

16
src/interfaces/libpq/libpq-fe.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California * Portions Copyright (c) 1994, Regents of the University of California
* *
* $Id: libpq-fe.h,v 1.86 2002/09/04 20:31:47 momjian Exp $ * $Id: libpq-fe.h,v 1.86.2.1 2006/05/21 20:20:48 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -248,12 +248,18 @@ extern PQnoticeProcessor PQsetNoticeProcessor(PGconn *conn,
/* === in fe-exec.c === */ /* === in fe-exec.c === */
/* Quoting strings before inclusion in queries. */ /* Quoting strings before inclusion in queries. */
extern size_t PQescapeString(char *to, const char *from, size_t length); extern size_t PQescapeStringConn(PGconn *conn,
extern unsigned char *PQescapeBytea(unsigned char *bintext, size_t binlen, char *to, const char *from, size_t length,
size_t *bytealen); int *error);
extern unsigned char *PQescapeByteaConn(PGconn *conn,
const unsigned char *from, size_t from_length,
size_t *to_length);
extern unsigned char *PQunescapeBytea(unsigned char *strtext, extern unsigned char *PQunescapeBytea(unsigned char *strtext,
size_t *retbuflen); size_t *retbuflen);
/* These forms are deprecated! */
extern size_t PQescapeString(char *to, const char *from, size_t length);
extern unsigned char *PQescapeBytea(unsigned char *from, size_t from_length,
size_t *to_length);
/* Simple synchronous query */ /* Simple synchronous query */
extern PGresult *PQexec(PGconn *conn, const char *query); extern PGresult *PQexec(PGconn *conn, const char *query);

5
src/interfaces/libpq/libpq-int.h
View File

@ -12,7 +12,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California * Portions Copyright (c) 1994, Regents of the University of California
* *
* $Id: libpq-int.h,v 1.60 2002/10/16 02:55:30 momjian Exp $ * $Id: libpq-int.h,v 1.60.2.1 2006/05/21 20:20:48 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -301,6 +301,9 @@ struct pg_conn
*/ */
extern char *const pgresStatus[]; extern char *const pgresStatus[];
/* Added for PQescapeString fix */
extern int PQ_static_client_encoding;
/* ---------------- /* ----------------
* Internal functions of libpq * Internal functions of libpq
* Functions declared here need to be visible across files of libpq, * Functions declared here need to be visible across files of libpq,

2
src/interfaces/libpq/libpqdll.def
View File

@ -93,3 +93,5 @@ EXPORTS
appendPQExpBuffer @ 91 appendPQExpBuffer @ 91
pg_encoding_to_char @ 92 pg_encoding_to_char @ 92
pg_utf_mblen @ 93 pg_utf_mblen @ 93
PQescapeStringConn @ 126
PQescapeByteaConn @ 127