Adding upstream version 1:9.16.44.upstream/1%9.16.44

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

1 files changed, 270 insertions, 0 deletions

diff --git a/lib/isc/base64.c b/lib/isc/base64.c
new file mode 100644
index 0000000..958ef4f
--- /dev/null
+++ b/lib/isc/base64.c
@@ -0,0 +1,270 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+
+#include <stdbool.h>
+
+#include <isc/base64.h>
+#include <isc/buffer.h>
+#include <isc/lex.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#define RETERR(x)                        \
+	do {                             \
+		isc_result_t _r = (x);   \
+		if (_r != ISC_R_SUCCESS) \
+			return ((_r));   \
+	} while (0)
+
+/*@{*/
+/*!
+ * These static functions are also present in lib/dns/rdata.c.  I'm not
+ * sure where they should go. -- bwelling
+ */
+static isc_result_t
+str_totext(const char *source, isc_buffer_t *target);
+
+static isc_result_t
+mem_tobuffer(isc_buffer_t *target, void *base, unsigned int length);
+
+static const char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvw"
+			     "xyz0123456789+/=";
+/*@}*/
+
+isc_result_t
+isc_base64_totext(isc_region_t *source, int wordlength, const char *wordbreak,
+		  isc_buffer_t *target) {
+	char buf[5];
+	unsigned int loops = 0;
+
+	if (wordlength < 4) {
+		wordlength = 4;
+	}
+
+	memset(buf, 0, sizeof(buf));
+	while (source->length > 2) {
+		buf[0] = base64[(source->base[0] >> 2) & 0x3f];
+		buf[1] = base64[((source->base[0] << 4) & 0x30) |
+				((source->base[1] >> 4) & 0x0f)];
+		buf[2] = base64[((source->base[1] << 2) & 0x3c) |
+				((source->base[2] >> 6) & 0x03)];
+		buf[3] = base64[source->base[2] & 0x3f];
+		RETERR(str_totext(buf, target));
+		isc_region_consume(source, 3);
+
+		loops++;
+		if (source->length != 0 && (int)((loops + 1) * 4) >= wordlength)
+		{
+			loops = 0;
+			RETERR(str_totext(wordbreak, target));
+		}
+	}
+	if (source->length == 2) {
+		buf[0] = base64[(source->base[0] >> 2) & 0x3f];
+		buf[1] = base64[((source->base[0] << 4) & 0x30) |
+				((source->base[1] >> 4) & 0x0f)];
+		buf[2] = base64[((source->base[1] << 2) & 0x3c)];
+		buf[3] = '=';
+		RETERR(str_totext(buf, target));
+		isc_region_consume(source, 2);
+	} else if (source->length == 1) {
+		buf[0] = base64[(source->base[0] >> 2) & 0x3f];
+		buf[1] = base64[((source->base[0] << 4) & 0x30)];
+		buf[2] = buf[3] = '=';
+		RETERR(str_totext(buf, target));
+		isc_region_consume(source, 1);
+	}
+	return (ISC_R_SUCCESS);
+}
+
+/*%
+ * State of a base64 decoding process in progress.
+ */
+typedef struct {
+	int length;	      /*%< Desired length of binary data or -1 */
+	isc_buffer_t *target; /*%< Buffer for resulting binary data */
+	int digits;	      /*%< Number of buffered base64 digits */
+	bool seen_end;	      /*%< True if "=" end marker seen */
+	int val[4];
+} base64_decode_ctx_t;
+
+static void
+base64_decode_init(base64_decode_ctx_t *ctx, int length, isc_buffer_t *target) {
+	ctx->digits = 0;
+	ctx->seen_end = false;
+	ctx->length = length;
+	ctx->target = target;
+}
+
+static isc_result_t
+base64_decode_char(base64_decode_ctx_t *ctx, int c) {
+	const char *s;
+
+	if (ctx->seen_end) {
+		return (ISC_R_BADBASE64);
+	}
+	if ((s = strchr(base64, c)) == NULL) {
+		return (ISC_R_BADBASE64);
+	}
+	ctx->val[ctx->digits++] = (int)(s - base64);
+	if (ctx->digits == 4) {
+		int n;
+		unsigned char buf[3];
+		if (ctx->val[0] == 64 || ctx->val[1] == 64) {
+			return (ISC_R_BADBASE64);
+		}
+		if (ctx->val[2] == 64 && ctx->val[3] != 64) {
+			return (ISC_R_BADBASE64);
+		}
+		/*
+		 * Check that bits that should be zero are.
+		 */
+		if (ctx->val[2] == 64 && (ctx->val[1] & 0xf) != 0) {
+			return (ISC_R_BADBASE64);
+		}
+		/*
+		 * We don't need to test for ctx->val[2] != 64 as
+		 * the bottom two bits of 64 are zero.
+		 */
+		if (ctx->val[3] == 64 && (ctx->val[2] & 0x3) != 0) {
+			return (ISC_R_BADBASE64);
+		}
+		n = (ctx->val[2] == 64) ? 1 : (ctx->val[3] == 64) ? 2 : 3;
+		if (n != 3) {
+			ctx->seen_end = true;
+			if (ctx->val[2] == 64) {
+				ctx->val[2] = 0;
+			}
+			if (ctx->val[3] == 64) {
+				ctx->val[3] = 0;
+			}
+		}
+		buf[0] = (ctx->val[0] << 2) | (ctx->val[1] >> 4);
+		buf[1] = (ctx->val[1] << 4) | (ctx->val[2] >> 2);
+		buf[2] = (ctx->val[2] << 6) | (ctx->val[3]);
+		RETERR(mem_tobuffer(ctx->target, buf, n));
+		if (ctx->length >= 0) {
+			if (n > ctx->length) {
+				return (ISC_R_BADBASE64);
+			} else {
+				ctx->length -= n;
+			}
+		}
+		ctx->digits = 0;
+	}
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+base64_decode_finish(base64_decode_ctx_t *ctx) {
+	if (ctx->length > 0) {
+		return (ISC_R_UNEXPECTEDEND);
+	}
+	if (ctx->digits != 0) {
+		return (ISC_R_BADBASE64);
+	}
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_base64_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) {
+	unsigned int before, after;
+	base64_decode_ctx_t ctx;
+	isc_textregion_t *tr;
+	isc_token_t token;
+	bool eol;
+
+	REQUIRE(length >= -2);
+
+	base64_decode_init(&ctx, length, target);
+
+	before = isc_buffer_usedlength(target);
+	while (!ctx.seen_end && (ctx.length != 0)) {
+		unsigned int i;
+
+		if (length > 0) {
+			eol = false;
+		} else {
+			eol = true;
+		}
+		RETERR(isc_lex_getmastertoken(lexer, &token,
+					      isc_tokentype_string, eol));
+		if (token.type != isc_tokentype_string) {
+			break;
+		}
+		tr = &token.value.as_textregion;
+		for (i = 0; i < tr->length; i++) {
+			RETERR(base64_decode_char(&ctx, tr->base[i]));
+		}
+	}
+	after = isc_buffer_usedlength(target);
+	if (ctx.length < 0 && !ctx.seen_end) {
+		isc_lex_ungettoken(lexer, &token);
+	}
+	RETERR(base64_decode_finish(&ctx));
+	if (length == -2 && before == after) {
+		return (ISC_R_UNEXPECTEDEND);
+	}
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_base64_decodestring(const char *cstr, isc_buffer_t *target) {
+	base64_decode_ctx_t ctx;
+
+	base64_decode_init(&ctx, -1, target);
+	for (;;) {
+		int c = *cstr++;
+		if (c == '\0') {
+			break;
+		}
+		if (c == ' ' || c == '\t' || c == '\n' || c == '\r') {
+			continue;
+		}
+		RETERR(base64_decode_char(&ctx, c));
+	}
+	RETERR(base64_decode_finish(&ctx));
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+str_totext(const char *source, isc_buffer_t *target) {
+	unsigned int l;
+	isc_region_t region;
+
+	isc_buffer_availableregion(target, &region);
+	l = strlen(source);
+
+	if (l > region.length) {
+		return (ISC_R_NOSPACE);
+	}
+
+	memmove(region.base, source, l);
+	isc_buffer_add(target, l);
+	return (ISC_R_SUCCESS);
+}
+
+static isc_result_t
+mem_tobuffer(isc_buffer_t *target, void *base, unsigned int length) {
+	isc_region_t tr;
+
+	isc_buffer_availableregion(target, &tr);
+	if (length > tr.length) {
+		return (ISC_R_NOSPACE);
+	}
+	memmove(tr.base, base, length);
+	isc_buffer_add(target, length);
+	return (ISC_R_SUCCESS);
+}