From 3b9b6d0b8e7f798023c9d109c490449d528fde80 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:59:48 +0200 Subject: Adding upstream version 1:9.18.19. Signed-off-by: Daniel Baumann --- lib/isc/base32.c | 443 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 443 insertions(+) create mode 100644 lib/isc/base32.c (limited to 'lib/isc/base32.c') diff --git a/lib/isc/base32.c b/lib/isc/base32.c new file mode 100644 index 0000000..90c37c7 --- /dev/null +++ b/lib/isc/base32.c @@ -0,0 +1,443 @@ +/* + * 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 + +#include +#include +#include +#include +#include +#include + +#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 base32[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567=" + "abcdefghijklmnopqrstuvwxyz234567"; +static const char base32hex[] = "0123456789ABCDEFGHIJKLMNOPQRSTUV=" + "0123456789abcdefghijklmnopqrstuv"; + +static isc_result_t +base32_totext(isc_region_t *source, int wordlength, const char *wordbreak, + isc_buffer_t *target, const char base[], char pad) { + char buf[9]; + unsigned int loops = 0; + + if (wordlength >= 0 && wordlength < 8) { + wordlength = 8; + } + + memset(buf, 0, sizeof(buf)); + while (source->length > 0) { + buf[0] = base[((source->base[0] >> 3) & 0x1f)]; /* 5 + */ + if (source->length == 1) { + buf[1] = base[(source->base[0] << 2) & 0x1c]; + buf[2] = buf[3] = buf[4] = pad; + buf[5] = buf[6] = buf[7] = pad; + RETERR(str_totext(buf, target)); + break; + } + buf[1] = base[((source->base[0] << 2) & 0x1c) | /* 3 = 8 */ + ((source->base[1] >> 6) & 0x03)]; /* 2 + */ + buf[2] = base[((source->base[1] >> 1) & 0x1f)]; /* 5 + */ + if (source->length == 2) { + buf[3] = base[(source->base[1] << 4) & 0x10]; + buf[4] = buf[5] = buf[6] = buf[7] = pad; + RETERR(str_totext(buf, target)); + break; + } + buf[3] = base[((source->base[1] << 4) & 0x10) | /* 1 = 8 */ + ((source->base[2] >> 4) & 0x0f)]; /* 4 + */ + if (source->length == 3) { + buf[4] = base[(source->base[2] << 1) & 0x1e]; + buf[5] = buf[6] = buf[7] = pad; + RETERR(str_totext(buf, target)); + break; + } + buf[4] = base[((source->base[2] << 1) & 0x1e) | /* 4 = 8 */ + ((source->base[3] >> 7) & 0x01)]; /* 1 + */ + buf[5] = base[((source->base[3] >> 2) & 0x1f)]; /* 5 + */ + if (source->length == 4) { + buf[6] = base[(source->base[3] << 3) & 0x18]; + buf[7] = pad; + RETERR(str_totext(buf, target)); + break; + } + buf[6] = base[((source->base[3] << 3) & 0x18) | /* 2 = 8 */ + ((source->base[4] >> 5) & 0x07)]; /* 3 + */ + buf[7] = base[source->base[4] & 0x1f]; /* 5 = 8 */ + RETERR(str_totext(buf, target)); + isc_region_consume(source, 5); + + loops++; + if (source->length != 0 && wordlength >= 0 && + (int)((loops + 1) * 8) >= wordlength) + { + loops = 0; + RETERR(str_totext(wordbreak, target)); + } + } + if (source->length > 0) { + isc_region_consume(source, source->length); + } + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_base32_totext(isc_region_t *source, int wordlength, const char *wordbreak, + isc_buffer_t *target) { + return (base32_totext(source, wordlength, wordbreak, target, base32, + '=')); +} + +isc_result_t +isc_base32hex_totext(isc_region_t *source, int wordlength, + const char *wordbreak, isc_buffer_t *target) { + return (base32_totext(source, wordlength, wordbreak, target, base32hex, + '=')); +} + +isc_result_t +isc_base32hexnp_totext(isc_region_t *source, int wordlength, + const char *wordbreak, isc_buffer_t *target) { + return (base32_totext(source, wordlength, wordbreak, target, base32hex, + 0)); +} + +/*% + * State of a base32 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 base32 digits */ + bool seen_end; /*%< True if "=" end marker seen */ + int val[8]; + const char *base; /*%< Which encoding we are using */ + int seen_32; /*%< Number of significant bytes if non + * zero */ + bool pad; /*%< Expect padding */ +} base32_decode_ctx_t; + +static void +base32_decode_init(base32_decode_ctx_t *ctx, int length, const char base[], + bool pad, isc_buffer_t *target) { + ctx->digits = 0; + ctx->seen_end = false; + ctx->seen_32 = 0; + ctx->length = length; + ctx->target = target; + ctx->base = base; + ctx->pad = pad; +} + +static isc_result_t +base32_decode_char(base32_decode_ctx_t *ctx, int c) { + const char *s; + unsigned int last; + + if (ctx->seen_end) { + return (ISC_R_BADBASE32); + } + if ((s = strchr(ctx->base, c)) == NULL) { + return (ISC_R_BADBASE32); + } + last = (unsigned int)(s - ctx->base); + + /* + * Handle lower case. + */ + if (last > 32) { + last -= 33; + } + + /* + * Check that padding is contiguous. + */ + if (last != 32 && ctx->seen_32 != 0) { + return (ISC_R_BADBASE32); + } + + /* + * If padding is not permitted flag padding as a error. + */ + if (last == 32 && !ctx->pad) { + return (ISC_R_BADBASE32); + } + + /* + * Check that padding starts at the right place and that + * bits that should be zero are. + * Record how many significant bytes in answer (seen_32). + */ + if (last == 32 && ctx->seen_32 == 0) { + switch (ctx->digits) { + case 0: + case 1: + return (ISC_R_BADBASE32); + case 2: + if ((ctx->val[1] & 0x03) != 0) { + return (ISC_R_BADBASE32); + } + ctx->seen_32 = 1; + break; + case 3: + return (ISC_R_BADBASE32); + case 4: + if ((ctx->val[3] & 0x0f) != 0) { + return (ISC_R_BADBASE32); + } + ctx->seen_32 = 2; + break; + case 5: + if ((ctx->val[4] & 0x01) != 0) { + return (ISC_R_BADBASE32); + } + ctx->seen_32 = 3; + break; + case 6: + return (ISC_R_BADBASE32); + case 7: + if ((ctx->val[6] & 0x07) != 0) { + return (ISC_R_BADBASE32); + } + ctx->seen_32 = 4; + break; + } + } + + /* + * Zero fill pad values. + */ + ctx->val[ctx->digits++] = (last == 32) ? 0 : last; + + if (ctx->digits == 8) { + int n = 5; + unsigned char buf[5]; + + if (ctx->seen_32 != 0) { + ctx->seen_end = true; + n = ctx->seen_32; + } + buf[0] = (ctx->val[0] << 3) | (ctx->val[1] >> 2); + buf[1] = (ctx->val[1] << 6) | (ctx->val[2] << 1) | + (ctx->val[3] >> 4); + buf[2] = (ctx->val[3] << 4) | (ctx->val[4] >> 1); + buf[3] = (ctx->val[4] << 7) | (ctx->val[5] << 2) | + (ctx->val[6] >> 3); + buf[4] = (ctx->val[6] << 5) | (ctx->val[7]); + RETERR(mem_tobuffer(ctx->target, buf, n)); + if (ctx->length >= 0) { + if (n > ctx->length) { + return (ISC_R_BADBASE32); + } else { + ctx->length -= n; + } + } + ctx->digits = 0; + } + return (ISC_R_SUCCESS); +} + +static isc_result_t +base32_decode_finish(base32_decode_ctx_t *ctx) { + if (ctx->length > 0) { + return (ISC_R_UNEXPECTEDEND); + } + /* + * Add missing padding if required. + */ + if (!ctx->pad && ctx->digits != 0) { + ctx->pad = true; + do { + RETERR(base32_decode_char(ctx, '=')); + } while (ctx->digits != 0); + } + if (ctx->digits != 0) { + return (ISC_R_BADBASE32); + } + return (ISC_R_SUCCESS); +} + +static isc_result_t +base32_tobuffer(isc_lex_t *lexer, const char base[], bool pad, + isc_buffer_t *target, int length) { + unsigned int before, after; + base32_decode_ctx_t ctx; + isc_textregion_t *tr; + isc_token_t token; + bool eol; + + REQUIRE(length >= -2); + + base32_decode_init(&ctx, length, base, pad, 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(base32_decode_char(&ctx, tr->base[i])); + } + } + after = isc_buffer_usedlength(target); + if (ctx.length < 0 && !ctx.seen_end) { + isc_lex_ungettoken(lexer, &token); + } + RETERR(base32_decode_finish(&ctx)); + if (length == -2 && before == after) { + return (ISC_R_UNEXPECTEDEND); + } + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_base32_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) { + return (base32_tobuffer(lexer, base32, true, target, length)); +} + +isc_result_t +isc_base32hex_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) { + return (base32_tobuffer(lexer, base32hex, true, target, length)); +} + +isc_result_t +isc_base32hexnp_tobuffer(isc_lex_t *lexer, isc_buffer_t *target, int length) { + return (base32_tobuffer(lexer, base32hex, false, target, length)); +} + +static isc_result_t +base32_decodestring(const char *cstr, const char base[], bool pad, + isc_buffer_t *target) { + base32_decode_ctx_t ctx; + + base32_decode_init(&ctx, -1, base, pad, target); + for (;;) { + int c = *cstr++; + if (c == '\0') { + break; + } + if (c == ' ' || c == '\t' || c == '\n' || c == '\r') { + continue; + } + RETERR(base32_decode_char(&ctx, c)); + } + RETERR(base32_decode_finish(&ctx)); + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_base32_decodestring(const char *cstr, isc_buffer_t *target) { + return (base32_decodestring(cstr, base32, true, target)); +} + +isc_result_t +isc_base32hex_decodestring(const char *cstr, isc_buffer_t *target) { + return (base32_decodestring(cstr, base32hex, true, target)); +} + +isc_result_t +isc_base32hexnp_decodestring(const char *cstr, isc_buffer_t *target) { + return (base32_decodestring(cstr, base32hex, false, target)); +} + +static isc_result_t +base32_decoderegion(isc_region_t *source, const char base[], bool pad, + isc_buffer_t *target) { + base32_decode_ctx_t ctx; + + base32_decode_init(&ctx, -1, base, pad, target); + while (source->length != 0) { + int c = *source->base; + RETERR(base32_decode_char(&ctx, c)); + isc_region_consume(source, 1); + } + RETERR(base32_decode_finish(&ctx)); + return (ISC_R_SUCCESS); +} + +isc_result_t +isc_base32_decoderegion(isc_region_t *source, isc_buffer_t *target) { + return (base32_decoderegion(source, base32, true, target)); +} + +isc_result_t +isc_base32hex_decoderegion(isc_region_t *source, isc_buffer_t *target) { + return (base32_decoderegion(source, base32hex, true, target)); +} + +isc_result_t +isc_base32hexnp_decoderegion(isc_region_t *source, isc_buffer_t *target) { + return (base32_decoderegion(source, base32hex, false, target)); +} + +static isc_result_t +str_totext(const char *source, isc_buffer_t *target) { + unsigned int l; + isc_region_t region; + + isc_buffer_availableregion(target, ®ion); + 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); +} -- cgit v1.2.3