1 files changed, 265 insertions, 0 deletions
diff --git a/contrib/pgcrypto/pgp-cfb.c b/contrib/pgcrypto/pgp-cfb.c
new file mode 100644
index 0000000..de41e82
--- /dev/null
+++ b/contrib/pgcrypto/pgp-cfb.c
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+/*
+ * pgp-cfb.c
+ *	  Implements both normal and PGP-specific CFB mode.
+ *
+ * Copyright (c) 2005 Marko Kreen
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *	  notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *	  notice, this list of conditions and the following disclaimer in the
+ *	  documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * contrib/pgcrypto/pgp-cfb.c
+ */
+
+#include "postgres.h"
+
+#include "pgp.h"
+#include "px.h"
+
+typedef int (*mix_data_t) (PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst);
+
+struct PGP_CFB
+{
+	PX_Cipher  *ciph;
+	int			block_size;
+	int			pos;
+	int			block_no;
+	int			resync;
+	uint8		fr[PGP_MAX_BLOCK];
+	uint8		fre[PGP_MAX_BLOCK];
+	uint8		encbuf[PGP_MAX_BLOCK];
+};
+
+int
+pgp_cfb_create(PGP_CFB **ctx_p, int algo, const uint8 *key, int key_len,
+			   int resync, uint8 *iv)
+{
+	int			res;
+	PX_Cipher  *ciph;
+	PGP_CFB    *ctx;
+
+	res = pgp_load_cipher(algo, &ciph);
+	if (res < 0)
+		return res;
+
+	res = px_cipher_init(ciph, key, key_len, NULL);
+	if (res < 0)
+	{
+		px_cipher_free(ciph);
+		return res;
+	}
+
+	ctx = palloc0(sizeof(*ctx));
+	ctx->ciph = ciph;
+	ctx->block_size = px_cipher_block_size(ciph);
+	ctx->resync = resync;
+
+	if (iv)
+		memcpy(ctx->fr, iv, ctx->block_size);
+
+	*ctx_p = ctx;
+	return 0;
+}
+
+void
+pgp_cfb_free(PGP_CFB *ctx)
+{
+	px_cipher_free(ctx->ciph);
+	px_memset(ctx, 0, sizeof(*ctx));
+	pfree(ctx);
+}
+
+/*
+ * Data processing for normal CFB.  (PGP_PKT_SYMENCRYPTED_DATA_MDC)
+ */
+static int
+mix_encrypt_normal(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	int			i;
+
+	for (i = ctx->pos; i < ctx->pos + len; i++)
+		*dst++ = ctx->encbuf[i] = ctx->fre[i] ^ (*data++);
+	ctx->pos += len;
+	return len;
+}
+
+static int
+mix_decrypt_normal(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	int			i;
+
+	for (i = ctx->pos; i < ctx->pos + len; i++)
+	{
+		ctx->encbuf[i] = *data++;
+		*dst++ = ctx->fre[i] ^ ctx->encbuf[i];
+	}
+	ctx->pos += len;
+	return len;
+}
+
+/*
+ * Data processing for old PGP CFB mode. (PGP_PKT_SYMENCRYPTED_DATA)
+ *
+ * The goal is to hide the horror from the rest of the code,
+ * thus its all concentrated here.
+ */
+static int
+mix_encrypt_resync(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	int			i,
+				n;
+
+	/* block #2 is 2 bytes long */
+	if (ctx->block_no == 2)
+	{
+		n = 2 - ctx->pos;
+		if (len < n)
+			n = len;
+		for (i = ctx->pos; i < ctx->pos + n; i++)
+			*dst++ = ctx->encbuf[i] = ctx->fre[i] ^ (*data++);
+
+		ctx->pos += n;
+		len -= n;
+
+		if (ctx->pos == 2)
+		{
+			memcpy(ctx->fr, ctx->encbuf + 2, ctx->block_size - 2);
+			memcpy(ctx->fr + ctx->block_size - 2, ctx->encbuf, 2);
+			ctx->pos = 0;
+			return n;
+		}
+	}
+	for (i = ctx->pos; i < ctx->pos + len; i++)
+		*dst++ = ctx->encbuf[i] = ctx->fre[i] ^ (*data++);
+	ctx->pos += len;
+	return len;
+}
+
+static int
+mix_decrypt_resync(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	int			i,
+				n;
+
+	/* block #2 is 2 bytes long */
+	if (ctx->block_no == 2)
+	{
+		n = 2 - ctx->pos;
+		if (len < n)
+			n = len;
+		for (i = ctx->pos; i < ctx->pos + n; i++)
+		{
+			ctx->encbuf[i] = *data++;
+			*dst++ = ctx->fre[i] ^ ctx->encbuf[i];
+		}
+		ctx->pos += n;
+		len -= n;
+
+		if (ctx->pos == 2)
+		{
+			memcpy(ctx->fr, ctx->encbuf + 2, ctx->block_size - 2);
+			memcpy(ctx->fr + ctx->block_size - 2, ctx->encbuf, 2);
+			ctx->pos = 0;
+			return n;
+		}
+	}
+	for (i = ctx->pos; i < ctx->pos + len; i++)
+	{
+		ctx->encbuf[i] = *data++;
+		*dst++ = ctx->fre[i] ^ ctx->encbuf[i];
+	}
+	ctx->pos += len;
+	return len;
+}
+
+/*
+ * common code for both encrypt and decrypt.
+ */
+static int
+cfb_process(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst,
+			mix_data_t mix_data)
+{
+	int			n;
+	int			res;
+
+	while (len > 0 && ctx->pos > 0)
+	{
+		n = ctx->block_size - ctx->pos;
+		if (len < n)
+			n = len;
+
+		n = mix_data(ctx, data, n, dst);
+		data += n;
+		dst += n;
+		len -= n;
+
+		if (ctx->pos == ctx->block_size)
+		{
+			memcpy(ctx->fr, ctx->encbuf, ctx->block_size);
+			ctx->pos = 0;
+		}
+	}
+
+	while (len > 0)
+	{
+		unsigned	rlen;
+
+		px_cipher_encrypt(ctx->ciph, 0, ctx->fr, ctx->block_size, ctx->fre, &rlen);
+		if (ctx->block_no < 5)
+			ctx->block_no++;
+
+		n = ctx->block_size;
+		if (len < n)
+			n = len;
+
+		res = mix_data(ctx, data, n, dst);
+		data += res;
+		dst += res;
+		len -= res;
+
+		if (ctx->pos == ctx->block_size)
+		{
+			memcpy(ctx->fr, ctx->encbuf, ctx->block_size);
+			ctx->pos = 0;
+		}
+	}
+	return 0;
+}
+
+/*
+ * public interface
+ */
+
+int
+pgp_cfb_encrypt(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	mix_data_t	mix = ctx->resync ? mix_encrypt_resync : mix_encrypt_normal;
+
+	return cfb_process(ctx, data, len, dst, mix);
+}
+
+int
+pgp_cfb_decrypt(PGP_CFB *ctx, const uint8 *data, int len, uint8 *dst)
+{
+	mix_data_t	mix = ctx->resync ? mix_decrypt_resync : mix_decrypt_normal;
+
+	return cfb_process(ctx, data, len, dst, mix);
+}