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-rw-r--r--src/common/Makefile10
-rw-r--r--src/common/ip.c260
-rw-r--r--src/common/md5.c348
3 files changed, 615 insertions, 3 deletions
diff --git a/src/common/Makefile b/src/common/Makefile
index 72b73697a8..a5fa649766 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -6,11 +6,15 @@
# This makefile generates two outputs:
#
# libpgcommon.a - contains object files with FRONTEND defined,
-# for use by client application and libraries
+# for use by client applications
#
# libpgcommon_srv.a - contains object files without FRONTEND defined,
# for use only by the backend binaries
#
+# You can also symlink/copy individual source files from this directory,
+# to compile with different options. (libpq does that, because it needs
+# to use -fPIC on some platforms.)
+#
# IDENTIFICATION
# src/common/Makefile
#
@@ -36,8 +40,8 @@ override CPPFLAGS += -DVAL_LDFLAGS_EX="\"$(LDFLAGS_EX)\""
override CPPFLAGS += -DVAL_LDFLAGS_SL="\"$(LDFLAGS_SL)\""
override CPPFLAGS += -DVAL_LIBS="\"$(LIBS)\""
-OBJS_COMMON = config_info.o controldata_utils.o exec.o keywords.o \
- pg_lzcompress.o pgfnames.o psprintf.o relpath.o rmtree.o \
+OBJS_COMMON = config_info.o controldata_utils.o exec.o ip.o keywords.o \
+ md5.o pg_lzcompress.o pgfnames.o psprintf.o relpath.o rmtree.o \
string.o username.o wait_error.o
OBJS_FRONTEND = $(OBJS_COMMON) fe_memutils.o restricted_token.o
diff --git a/src/common/ip.c b/src/common/ip.c
new file mode 100644
index 0000000000..797d9109ab
--- /dev/null
+++ b/src/common/ip.c
@@ -0,0 +1,260 @@
+/*-------------------------------------------------------------------------
+ *
+ * ip.c
+ * IPv6-aware network access.
+ *
+ * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * src/common/ip.c
+ *
+ * This file and the IPV6 implementation were initially provided by
+ * Nigel Kukard <nkukard@lbsd.net>, Linux Based Systems Design
+ * http://www.lbsd.net.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef FRONTEND
+#include "postgres.h"
+#else
+#include "postgres_fe.h"
+#endif
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#ifdef HAVE_NETINET_TCP_H
+#include <netinet/tcp.h>
+#endif
+#include <arpa/inet.h>
+#include <sys/file.h>
+
+#include "common/ip.h"
+
+
+
+#ifdef HAVE_UNIX_SOCKETS
+static int getaddrinfo_unix(const char *path,
+ const struct addrinfo * hintsp,
+ struct addrinfo ** result);
+
+static int getnameinfo_unix(const struct sockaddr_un * sa, int salen,
+ char *node, int nodelen,
+ char *service, int servicelen,
+ int flags);
+#endif
+
+
+/*
+ * pg_getaddrinfo_all - get address info for Unix, IPv4 and IPv6 sockets
+ */
+int
+pg_getaddrinfo_all(const char *hostname, const char *servname,
+ const struct addrinfo * hintp, struct addrinfo ** result)
+{
+ int rc;
+
+ /* not all versions of getaddrinfo() zero *result on failure */
+ *result = NULL;
+
+#ifdef HAVE_UNIX_SOCKETS
+ if (hintp->ai_family == AF_UNIX)
+ return getaddrinfo_unix(servname, hintp, result);
+#endif
+
+ /* NULL has special meaning to getaddrinfo(). */
+ rc = getaddrinfo((!hostname || hostname[0] == '\0') ? NULL : hostname,
+ servname, hintp, result);
+
+ return rc;
+}
+
+
+/*
+ * pg_freeaddrinfo_all - free addrinfo structures for IPv4, IPv6, or Unix
+ *
+ * Note: the ai_family field of the original hint structure must be passed
+ * so that we can tell whether the addrinfo struct was built by the system's
+ * getaddrinfo() routine or our own getaddrinfo_unix() routine. Some versions
+ * of getaddrinfo() might be willing to return AF_UNIX addresses, so it's
+ * not safe to look at ai_family in the addrinfo itself.
+ */
+void
+pg_freeaddrinfo_all(int hint_ai_family, struct addrinfo * ai)
+{
+#ifdef HAVE_UNIX_SOCKETS
+ if (hint_ai_family == AF_UNIX)
+ {
+ /* struct was built by getaddrinfo_unix (see pg_getaddrinfo_all) */
+ while (ai != NULL)
+ {
+ struct addrinfo *p = ai;
+
+ ai = ai->ai_next;
+ free(p->ai_addr);
+ free(p);
+ }
+ }
+ else
+#endif /* HAVE_UNIX_SOCKETS */
+ {
+ /* struct was built by getaddrinfo() */
+ if (ai != NULL)
+ freeaddrinfo(ai);
+ }
+}
+
+
+/*
+ * pg_getnameinfo_all - get name info for Unix, IPv4 and IPv6 sockets
+ *
+ * The API of this routine differs from the standard getnameinfo() definition
+ * in two ways: first, the addr parameter is declared as sockaddr_storage
+ * rather than struct sockaddr, and second, the node and service fields are
+ * guaranteed to be filled with something even on failure return.
+ */
+int
+pg_getnameinfo_all(const struct sockaddr_storage * addr, int salen,
+ char *node, int nodelen,
+ char *service, int servicelen,
+ int flags)
+{
+ int rc;
+
+#ifdef HAVE_UNIX_SOCKETS
+ if (addr && addr->ss_family == AF_UNIX)
+ rc = getnameinfo_unix((const struct sockaddr_un *) addr, salen,
+ node, nodelen,
+ service, servicelen,
+ flags);
+ else
+#endif
+ rc = getnameinfo((const struct sockaddr *) addr, salen,
+ node, nodelen,
+ service, servicelen,
+ flags);
+
+ if (rc != 0)
+ {
+ if (node)
+ strlcpy(node, "???", nodelen);
+ if (service)
+ strlcpy(service, "???", servicelen);
+ }
+
+ return rc;
+}
+
+
+#if defined(HAVE_UNIX_SOCKETS)
+
+/* -------
+ * getaddrinfo_unix - get unix socket info using IPv6-compatible API
+ *
+ * Bugs: only one addrinfo is set even though hintsp is NULL or
+ * ai_socktype is 0
+ * AI_CANONNAME is not supported.
+ * -------
+ */
+static int
+getaddrinfo_unix(const char *path, const struct addrinfo * hintsp,
+ struct addrinfo ** result)
+{
+ struct addrinfo hints;
+ struct addrinfo *aip;
+ struct sockaddr_un *unp;
+
+ *result = NULL;
+
+ MemSet(&hints, 0, sizeof(hints));
+
+ if (strlen(path) >= sizeof(unp->sun_path))
+ return EAI_FAIL;
+
+ if (hintsp == NULL)
+ {
+ hints.ai_family = AF_UNIX;
+ hints.ai_socktype = SOCK_STREAM;
+ }
+ else
+ memcpy(&hints, hintsp, sizeof(hints));
+
+ if (hints.ai_socktype == 0)
+ hints.ai_socktype = SOCK_STREAM;
+
+ if (hints.ai_family != AF_UNIX)
+ {
+ /* shouldn't have been called */
+ return EAI_FAIL;
+ }
+
+ aip = calloc(1, sizeof(struct addrinfo));
+ if (aip == NULL)
+ return EAI_MEMORY;
+
+ unp = calloc(1, sizeof(struct sockaddr_un));
+ if (unp == NULL)
+ {
+ free(aip);
+ return EAI_MEMORY;
+ }
+
+ aip->ai_family = AF_UNIX;
+ aip->ai_socktype = hints.ai_socktype;
+ aip->ai_protocol = hints.ai_protocol;
+ aip->ai_next = NULL;
+ aip->ai_canonname = NULL;
+ *result = aip;
+
+ unp->sun_family = AF_UNIX;
+ aip->ai_addr = (struct sockaddr *) unp;
+ aip->ai_addrlen = sizeof(struct sockaddr_un);
+
+ strcpy(unp->sun_path, path);
+
+#ifdef HAVE_STRUCT_SOCKADDR_STORAGE_SS_LEN
+ unp->sun_len = sizeof(struct sockaddr_un);
+#endif
+
+ return 0;
+}
+
+/*
+ * Convert an address to a hostname.
+ */
+static int
+getnameinfo_unix(const struct sockaddr_un * sa, int salen,
+ char *node, int nodelen,
+ char *service, int servicelen,
+ int flags)
+{
+ int ret = -1;
+
+ /* Invalid arguments. */
+ if (sa == NULL || sa->sun_family != AF_UNIX ||
+ (node == NULL && service == NULL))
+ return EAI_FAIL;
+
+ if (node)
+ {
+ ret = snprintf(node, nodelen, "%s", "[local]");
+ if (ret == -1 || ret > nodelen)
+ return EAI_MEMORY;
+ }
+
+ if (service)
+ {
+ ret = snprintf(service, servicelen, "%s", sa->sun_path);
+ if (ret == -1 || ret > servicelen)
+ return EAI_MEMORY;
+ }
+
+ return 0;
+}
+#endif /* HAVE_UNIX_SOCKETS */
diff --git a/src/common/md5.c b/src/common/md5.c
new file mode 100644
index 0000000000..6dad16529c
--- /dev/null
+++ b/src/common/md5.c
@@ -0,0 +1,348 @@
+/*
+ * md5.c
+ *
+ * Implements the MD5 Message-Digest Algorithm as specified in
+ * RFC 1321. This implementation is a simple one, in that it
+ * needs every input byte to be buffered before doing any
+ * calculations. I do not expect this file to be used for
+ * general purpose MD5'ing of large amounts of data, only for
+ * generating hashed passwords from limited input.
+ *
+ * Sverre H. Huseby <sverrehu@online.no>
+ *
+ * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ * src/common/md5.c
+ */
+
+#ifndef FRONTEND
+#include "postgres.h"
+#else
+#include "postgres_fe.h"
+#endif
+
+#include "common/md5.h"
+
+
+/*
+ * PRIVATE FUNCTIONS
+ */
+
+
+/*
+ * The returned array is allocated using malloc. the caller should free it
+ * when it is no longer needed.
+ */
+static uint8 *
+createPaddedCopyWithLength(const uint8 *b, uint32 *l)
+{
+ uint8 *ret;
+ uint32 q;
+ uint32 len,
+ newLen448;
+ uint32 len_high,
+ len_low; /* 64-bit value split into 32-bit sections */
+
+ len = ((b == NULL) ? 0 : *l);
+ newLen448 = len + 64 - (len % 64) - 8;
+ if (newLen448 <= len)
+ newLen448 += 64;
+
+ *l = newLen448 + 8;
+ if ((ret = (uint8 *) malloc(sizeof(uint8) * *l)) == NULL)
+ return NULL;
+
+ if (b != NULL)
+ memcpy(ret, b, sizeof(uint8) * len);
+
+ /* pad */
+ ret[len] = 0x80;
+ for (q = len + 1; q < newLen448; q++)
+ ret[q] = 0x00;
+
+ /* append length as a 64 bit bitcount */
+ len_low = len;
+ /* split into two 32-bit values */
+ /* we only look at the bottom 32-bits */
+ len_high = len >> 29;
+ len_low <<= 3;
+ q = newLen448;
+ ret[q++] = (len_low & 0xff);
+ len_low >>= 8;
+ ret[q++] = (len_low & 0xff);
+ len_low >>= 8;
+ ret[q++] = (len_low & 0xff);
+ len_low >>= 8;
+ ret[q++] = (len_low & 0xff);
+ ret[q++] = (len_high & 0xff);
+ len_high >>= 8;
+ ret[q++] = (len_high & 0xff);
+ len_high >>= 8;
+ ret[q++] = (len_high & 0xff);
+ len_high >>= 8;
+ ret[q] = (len_high & 0xff);
+
+ return ret;
+}
+
+#define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
+#define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
+#define H(x, y, z) ((x) ^ (y) ^ (z))
+#define I(x, y, z) ((y) ^ ((x) | ~(z)))
+#define ROT_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
+
+static void
+doTheRounds(uint32 X[16], uint32 state[4])
+{
+ uint32 a,
+ b,
+ c,
+ d;
+
+ a = state[0];
+ b = state[1];
+ c = state[2];
+ d = state[3];
+
+ /* round 1 */
+ a = b + ROT_LEFT((a + F(b, c, d) + X[0] + 0xd76aa478), 7); /* 1 */
+ d = a + ROT_LEFT((d + F(a, b, c) + X[1] + 0xe8c7b756), 12); /* 2 */
+ c = d + ROT_LEFT((c + F(d, a, b) + X[2] + 0x242070db), 17); /* 3 */
+ b = c + ROT_LEFT((b + F(c, d, a) + X[3] + 0xc1bdceee), 22); /* 4 */
+ a = b + ROT_LEFT((a + F(b, c, d) + X[4] + 0xf57c0faf), 7); /* 5 */
+ d = a + ROT_LEFT((d + F(a, b, c) + X[5] + 0x4787c62a), 12); /* 6 */
+ c = d + ROT_LEFT((c + F(d, a, b) + X[6] + 0xa8304613), 17); /* 7 */
+ b = c + ROT_LEFT((b + F(c, d, a) + X[7] + 0xfd469501), 22); /* 8 */
+ a = b + ROT_LEFT((a + F(b, c, d) + X[8] + 0x698098d8), 7); /* 9 */
+ d = a + ROT_LEFT((d + F(a, b, c) + X[9] + 0x8b44f7af), 12); /* 10 */
+ c = d + ROT_LEFT((c + F(d, a, b) + X[10] + 0xffff5bb1), 17); /* 11 */
+ b = c + ROT_LEFT((b + F(c, d, a) + X[11] + 0x895cd7be), 22); /* 12 */
+ a = b + ROT_LEFT((a + F(b, c, d) + X[12] + 0x6b901122), 7); /* 13 */
+ d = a + ROT_LEFT((d + F(a, b, c) + X[13] + 0xfd987193), 12); /* 14 */
+ c = d + ROT_LEFT((c + F(d, a, b) + X[14] + 0xa679438e), 17); /* 15 */
+ b = c + ROT_LEFT((b + F(c, d, a) + X[15] + 0x49b40821), 22); /* 16 */
+
+ /* round 2 */
+ a = b + ROT_LEFT((a + G(b, c, d) + X[1] + 0xf61e2562), 5); /* 17 */
+ d = a + ROT_LEFT((d + G(a, b, c) + X[6] + 0xc040b340), 9); /* 18 */
+ c = d + ROT_LEFT((c + G(d, a, b) + X[11] + 0x265e5a51), 14); /* 19 */
+ b = c + ROT_LEFT((b + G(c, d, a) + X[0] + 0xe9b6c7aa), 20); /* 20 */
+ a = b + ROT_LEFT((a + G(b, c, d) + X[5] + 0xd62f105d), 5); /* 21 */
+ d = a + ROT_LEFT((d + G(a, b, c) + X[10] + 0x02441453), 9); /* 22 */
+ c = d + ROT_LEFT((c + G(d, a, b) + X[15] + 0xd8a1e681), 14); /* 23 */
+ b = c + ROT_LEFT((b + G(c, d, a) + X[4] + 0xe7d3fbc8), 20); /* 24 */
+ a = b + ROT_LEFT((a + G(b, c, d) + X[9] + 0x21e1cde6), 5); /* 25 */
+ d = a + ROT_LEFT((d + G(a, b, c) + X[14] + 0xc33707d6), 9); /* 26 */
+ c = d + ROT_LEFT((c + G(d, a, b) + X[3] + 0xf4d50d87), 14); /* 27 */
+ b = c + ROT_LEFT((b + G(c, d, a) + X[8] + 0x455a14ed), 20); /* 28 */
+ a = b + ROT_LEFT((a + G(b, c, d) + X[13] + 0xa9e3e905), 5); /* 29 */
+ d = a + ROT_LEFT((d + G(a, b, c) + X[2] + 0xfcefa3f8), 9); /* 30 */
+ c = d + ROT_LEFT((c + G(d, a, b) + X[7] + 0x676f02d9), 14); /* 31 */
+ b = c + ROT_LEFT((b + G(c, d, a) + X[12] + 0x8d2a4c8a), 20); /* 32 */
+
+ /* round 3 */
+ a = b + ROT_LEFT((a + H(b, c, d) + X[5] + 0xfffa3942), 4); /* 33 */
+ d = a + ROT_LEFT((d + H(a, b, c) + X[8] + 0x8771f681), 11); /* 34 */
+ c = d + ROT_LEFT((c + H(d, a, b) + X[11] + 0x6d9d6122), 16); /* 35 */
+ b = c + ROT_LEFT((b + H(c, d, a) + X[14] + 0xfde5380c), 23); /* 36 */
+ a = b + ROT_LEFT((a + H(b, c, d) + X[1] + 0xa4beea44), 4); /* 37 */
+ d = a + ROT_LEFT((d + H(a, b, c) + X[4] + 0x4bdecfa9), 11); /* 38 */
+ c = d + ROT_LEFT((c + H(d, a, b) + X[7] + 0xf6bb4b60), 16); /* 39 */
+ b = c + ROT_LEFT((b + H(c, d, a) + X[10] + 0xbebfbc70), 23); /* 40 */
+ a = b + ROT_LEFT((a + H(b, c, d) + X[13] + 0x289b7ec6), 4); /* 41 */
+ d = a + ROT_LEFT((d + H(a, b, c) + X[0] + 0xeaa127fa), 11); /* 42 */
+ c = d + ROT_LEFT((c + H(d, a, b) + X[3] + 0xd4ef3085), 16); /* 43 */
+ b = c + ROT_LEFT((b + H(c, d, a) + X[6] + 0x04881d05), 23); /* 44 */
+ a = b + ROT_LEFT((a + H(b, c, d) + X[9] + 0xd9d4d039), 4); /* 45 */
+ d = a + ROT_LEFT((d + H(a, b, c) + X[12] + 0xe6db99e5), 11); /* 46 */
+ c = d + ROT_LEFT((c + H(d, a, b) + X[15] + 0x1fa27cf8), 16); /* 47 */
+ b = c + ROT_LEFT((b + H(c, d, a) + X[2] + 0xc4ac5665), 23); /* 48 */
+
+ /* round 4 */
+ a = b + ROT_LEFT((a + I(b, c, d) + X[0] + 0xf4292244), 6); /* 49 */
+ d = a + ROT_LEFT((d + I(a, b, c) + X[7] + 0x432aff97), 10); /* 50 */
+ c = d + ROT_LEFT((c + I(d, a, b) + X[14] + 0xab9423a7), 15); /* 51 */
+ b = c + ROT_LEFT((b + I(c, d, a) + X[5] + 0xfc93a039), 21); /* 52 */
+ a = b + ROT_LEFT((a + I(b, c, d) + X[12] + 0x655b59c3), 6); /* 53 */
+ d = a + ROT_LEFT((d + I(a, b, c) + X[3] + 0x8f0ccc92), 10); /* 54 */
+ c = d + ROT_LEFT((c + I(d, a, b) + X[10] + 0xffeff47d), 15); /* 55 */
+ b = c + ROT_LEFT((b + I(c, d, a) + X[1] + 0x85845dd1), 21); /* 56 */
+ a = b + ROT_LEFT((a + I(b, c, d) + X[8] + 0x6fa87e4f), 6); /* 57 */
+ d = a + ROT_LEFT((d + I(a, b, c) + X[15] + 0xfe2ce6e0), 10); /* 58 */
+ c = d + ROT_LEFT((c + I(d, a, b) + X[6] + 0xa3014314), 15); /* 59 */
+ b = c + ROT_LEFT((b + I(c, d, a) + X[13] + 0x4e0811a1), 21); /* 60 */
+ a = b + ROT_LEFT((a + I(b, c, d) + X[4] + 0xf7537e82), 6); /* 61 */
+ d = a + ROT_LEFT((d + I(a, b, c) + X[11] + 0xbd3af235), 10); /* 62 */
+ c = d + ROT_LEFT((c + I(d, a, b) + X[2] + 0x2ad7d2bb), 15); /* 63 */
+ b = c + ROT_LEFT((b + I(c, d, a) + X[9] + 0xeb86d391), 21); /* 64 */
+
+ state[0] += a;
+ state[1] += b;
+ state[2] += c;
+ state[3] += d;
+}
+
+static int
+calculateDigestFromBuffer(const uint8 *b, uint32 len, uint8 sum[16])
+{
+ register uint32 i,
+ j,
+ k,
+ newI;
+ uint32 l;
+ uint8 *input;
+ register uint32 *wbp;
+ uint32 workBuff[16],
+ state[4];
+
+ l = len;
+
+ state[0] = 0x67452301;
+ state[1] = 0xEFCDAB89;
+ state[2] = 0x98BADCFE;
+ state[3] = 0x10325476;
+
+ if ((input = createPaddedCopyWithLength(b, &l)) == NULL)
+ return 0;
+
+ for (i = 0;;)
+ {
+ if ((newI = i + 16 * 4) > l)
+ break;
+ k = i + 3;
+ for (j = 0; j < 16; j++)
+ {
+ wbp = (workBuff + j);
+ *wbp = input[k--];
+ *wbp <<= 8;
+ *wbp |= input[k--];
+ *wbp <<= 8;
+ *wbp |= input[k--];
+ *wbp <<= 8;
+ *wbp |= input[k];
+ k += 7;
+ }
+ doTheRounds(workBuff, state);
+ i = newI;
+ }
+ free(input);
+
+ j = 0;
+ for (i = 0; i < 4; i++)
+ {
+ k = state[i];
+ sum[j++] = (k & 0xff);
+ k >>= 8;
+ sum[j++] = (k & 0xff);
+ k >>= 8;
+ sum[j++] = (k & 0xff);
+ k >>= 8;
+ sum[j++] = (k & 0xff);
+ }
+ return 1;
+}
+
+static void
+bytesToHex(uint8 b[16], char *s)
+{
+ static const char *hex = "0123456789abcdef";
+ int q,
+ w;
+
+ for (q = 0, w = 0; q < 16; q++)
+ {
+ s[w++] = hex[(b[q] >> 4) & 0x0F];
+ s[w++] = hex[b[q] & 0x0F];
+ }
+ s[w] = '\0';
+}
+
+/*
+ * PUBLIC FUNCTIONS
+ */
+
+/*
+ * pg_md5_hash
+ *
+ * Calculates the MD5 sum of the bytes in a buffer.
+ *
+ * SYNOPSIS #include "md5.h"
+ * int pg_md5_hash(const void *buff, size_t len, char *hexsum)
+ *
+ * INPUT buff the buffer containing the bytes that you want
+ * the MD5 sum of.
+ * len number of bytes in the buffer.
+ *
+ * OUTPUT hexsum the MD5 sum as a '\0'-terminated string of
+ * hexadecimal digits. an MD5 sum is 16 bytes long.
+ * each byte is represented by two heaxadecimal
+ * characters. you thus need to provide an array
+ * of 33 characters, including the trailing '\0'.
+ *
+ * RETURNS false on failure (out of memory for internal buffers) or
+ * true on success.
+ *
+ * STANDARDS MD5 is described in RFC 1321.
+ *
+ * AUTHOR Sverre H. Huseby <sverrehu@online.no>
+ *
+ */
+bool
+pg_md5_hash(const void *buff, size_t len, char *hexsum)
+{
+ uint8 sum[16];
+
+ if (!calculateDigestFromBuffer(buff, len, sum))
+ return false;
+
+ bytesToHex(sum, hexsum);
+ return true;
+}
+
+bool
+pg_md5_binary(const void *buff, size_t len, void *outbuf)
+{
+ if (!calculateDigestFromBuffer(buff, len, outbuf))
+ return false;
+ return true;
+}
+
+
+/*
+ * Computes MD5 checksum of "passwd" (a null-terminated string) followed
+ * by "salt" (which need not be null-terminated).
+ *
+ * Output format is "md5" followed by a 32-hex-digit MD5 checksum.
+ * Hence, the output buffer "buf" must be at least 36 bytes long.
+ *
+ * Returns TRUE if okay, FALSE on error (out of memory).
+ */
+bool
+pg_md5_encrypt(const char *passwd, const char *salt, size_t salt_len,
+ char *buf)
+{
+ size_t passwd_len = strlen(passwd);
+
+ /* +1 here is just to avoid risk of unportable malloc(0) */
+ char *crypt_buf = malloc(passwd_len + salt_len + 1);
+ bool ret;
+
+ if (!crypt_buf)
+ return false;
+
+ /*
+ * Place salt at the end because it may be known by users trying to crack
+ * the MD5 output.
+ */
+ memcpy(crypt_buf, passwd, passwd_len);
+ memcpy(crypt_buf + passwd_len, salt, salt_len);
+
+ strcpy(buf, "md5");
+ ret = pg_md5_hash(crypt_buf, passwd_len + salt_len, buf + 3);
+
+ free(crypt_buf);
+
+ return ret;
+}