--- /dev/null
+/* -*-c-*-
+ *
+ * Binary base-conversion encoding and decoding (base64, base32, etc.)
+ *
+ * (c) 1997 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the mLib utilities library.
+ *
+ * mLib is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * mLib is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with mLib; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "alloc.h"
+#include "codec.h"
+#include "dstr.h"
+#include "sub.h"
+
+#include "base64.h"
+#include "base32.h"
+#include "hex.h"
+
+/*----- Important tables --------------------------------------------------*/
+
+/* --- Magic constants --- */
+
+#define NV -1 /* Not valid */
+#define PC -2 /* Padding character */
+#define NL -3 /* Newline character */
+
+/* --- Base64 --- */
+
+static const char
+ encodemap_base64[] = { "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+/" },
+ encodemap_file64[] = { "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789+%" },
+ encodemap_base64url[] = { "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "abcdefghijklmnopqrstuvwxyz"
+ "0123456789-_" };
+
+static const signed char decodemap_base64[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, 62, NV, NV, NV, 63, /* 2x */
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, NV, NV, NV, PC, NV, NV, /* 3x */
+ NV, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 4x */
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, NV, NV, NV, NV, NV, /* 5x */
+ NV, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36 ,37, 38, 39, 40, /* 6x */
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, NV, NV, NV, NV, NV /* 7x */
+}, decodemap_file64[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, 63, NV, NV, NV, NV, NV, 62, NV, NV, NV, NV, /* 2x */
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, NV, NV, NV, PC, NV, NV, /* 3x */
+ NV, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 4x */
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, NV, NV, NV, NV, NV, /* 5x */
+ NV, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36 ,37, 38, 39, 40, /* 6x */
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, NV, NV, NV, NV, NV /* 7x */
+}, decodemap_base64url[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, 62, NV, NV, /* 2x */
+ 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, NV, NV, NV, PC, NV, NV, /* 3x */
+ NV, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 4x */
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, NV, NV, NV, NV, 63, /* 5x */
+ NV, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36 ,37, 38, 39, 40, /* 6x */
+ 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, NV, NV, NV, NV, NV /* 7x */
+};
+
+/* --- Base32 --- */
+
+static const char
+ encodemap_base32[] = { "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567" },
+ encodemap_base32hex[] = { "0123456789ABCDEFGHIJKLMNOPQRSTUV" };
+
+static const signed char decodemap_base32[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 2x */
+ NV, NV, 26, 27, 28, 29, 30, 31, NV, NV, NV, NV, NV, PC, NV, NV, /* 3x */
+ NV, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 4x */
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, NV, NV, NV, NV, NV, /* 5x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 6x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 7x */
+}, decodemap_base32hex[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 2x */
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, NV, NV, NV, PC, NV, NV, /* 3x */
+ NV, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, /* 4x */
+ 25, 26, 27, 28, 29, 30, 31, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 5x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 6x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 7x */
+};
+
+/* --- Hex --- */
+
+static const char
+ encodemap_hex[] = { "0123456789ABCDEF" };
+
+static const signed char decodemap_hex[] = {
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NL, NV, NV, NL, NV, NV, /* 0x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 1x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 2x */
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, NV, NV, NV, NV, NV, NV, /* 3x */
+ NV, 10, 11, 12, 13, 14, 15, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 4x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 5x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 6x */
+ NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, NV, /* 7x */
+};
+
+/*----- Base conversion macros --------------------------------------------*/
+
+/* --- @BASECONV@ --- *
+ *
+ * Arguments: @x@ = an input digit of width @IWD@ bits
+ * @iwd@ = input digit width in bits
+ * @owd@ = output digit width in bits
+ * @put@ = function or macro to output a digit
+ *
+ * Use: Inserts the bits of @x@ into an accumulator. As digits @y@
+ * of with @owd@ become ready, @put(y)@ is invoked to emit them.
+ */
+
+#define BASECONV(x, iwd, owd, put) do { \
+ a = (a << iwd) | x; \
+ nb += iwd; \
+ while (nb >= owd) { \
+ nb -= owd; \
+ put((a >> nb) & ((1 << owd) - 1)); \
+ } \
+} while (0)
+
+/* --- @BASECONV_FLUSH@ --- *
+ *
+ * Arguments: @iwd@ = input digit width in bits
+ * @owd@ = output digit width in bits
+ * @put@ = function or macro to output a digit
+ *
+ * Use: Flushes remaining digits from the base-conversion shift
+ * register. The bits in the shift register are padded on the
+ * right with zeros. Digits of width @owd@ are emitted by
+ * invoking @put@.
+ */
+
+#define BASECONV_FLUSH(iwd, owd, put) do { \
+ if (nb) { \
+ while (nb < owd) { a <<= iwd; nb += iwd; } \
+ nb -= owd; \
+ put((a >> nb) & ((1 << owd) - 1)); \
+ } \
+} while (0)
+
+/* --- @BASECONV_PAD@ --- *
+ *
+ * Arguments: @iwd@ = input digit width in bits
+ * @owd@ = output digit width in bits
+ * @pad@ = function or macro to output padding
+ *
+ * Use: Invokes @pad@ sufficiently often to realign the shift
+ * register.
+ */
+
+#define BASECONV_PAD(iwd, owd, pad) do { \
+ for (;;) { \
+ while (nb >= owd) { pad; nb -= owd; } \
+ if (!nb) break; \
+ nb += iwd; \
+ } \
+} while (0)
+
+#define NULL_PAD(iwd, owd, pad) do ; while (0)
+
+/*----- Lists of things to make -------------------------------------------*/
+
+#define CODECS(_) \
+ /* NAME, CTXN, ACC */ \
+ _(base64, base64, acc) \
+ _(file64, base64, acc) \
+ _(base64url, base64, acc) \
+ _(base32, base32, accl) \
+ _(base32hex, base32, accl) \
+ _(hex, hex, acc)
+
+#define CTXS(_) \
+ /* CTXN, WD, ACC */ \
+ _(base64, 6, acc) \
+ _(base32, 5, accl) \
+ _(hex, 4, acc)
+
+#define base64_PADDING BASECONV_PAD
+#define base64_FLAGMASK ~(CDCF_LOWERC | CDCF_IGNCASE)
+#define base64_FLAGXOR 0
+#define base64_OLDFLAGS CDCF_IGNJUNK
+
+#define base32_PADDING BASECONV_PAD
+#define base32_FLAGMASK ~0
+#define base32_FLAGXOR 0
+#define base32_OLDFLAGS CDCF_IGNJUNK
+
+#define hex_PADDING NULL_PAD
+#define hex_FLAGMASK ~0
+#define hex_FLAGXOR 0
+#define hex_OLDFLAGS (CDCF_IGNJUNK | CDCF_LOWERC)
+
+/*----- Data structures ---------------------------------------------------*/
+
+#define OBJ(ctxn, wd, acc) \
+ \
+typedef struct ctxn##_codec { \
+ codec c; \
+ ctxn##_ctx ctx; \
+ const char *encodemap; \
+ const signed char *decodemap; \
+} ctxn##_codec;
+
+CTXS(OBJ)
+
+/*----- State packing -----------------------------------------------------*
+ *
+ * These macros convert between the state required by the new encoding and
+ * decoding core and the old externally-visible context structures. It's
+ * unpleasant, I know; maybe we can drop the old interface later.
+ */
+
+enum {
+ ST_MAIN, /* Main decoding state */
+ ST_PAD, /* Decoding trailing padding */
+ ST_END /* Finished decoding */
+};
+
+#define STATE_UNPACK(acc) \
+ unsigned long a = (ctx->acc >> 0) & 0xffff; \
+ unsigned nb = (ctx->acc >> 16) & 0xff; \
+ unsigned st = (ctx->acc >> 24) & 0xff; \
+ unsigned f = ctx->qsz;
+
+#define STATE_PACK(acc) do { \
+ ctx->acc = (((a & 0xffff) << 0) | \
+ (((unsigned long)nb & 0xff) << 16) | \
+ (((unsigned long)st & 0xff) << 24)); \
+} while (0)
+
+/*----- Main encoder and decoder ------------------------------------------*/
+
+#define WRAP(stuff) do { \
+ if (maxln && lnlen >= maxln) { \
+ dstr_puts(d, ctx->indent); \
+ lnlen = 0; \
+ } \
+ stuff \
+ lnlen++; \
+} while (0)
+
+#define PUTWRAP(x) WRAP({ \
+ char ch = encodemap[x]; \
+ if (f & CDCF_LOWERC) ch = tolower((unsigned char)ch); \
+ DPUTC(d, ch); \
+})
+
+#define PADWRAP WRAP({ DPUTC(d, '='); })
+
+#define PUTRAW(x) DPUTC(d, x)
+
+#define ENCODER(ctxn, wd, acc) \
+ \
+/* --- @CTXN_doencode@ --- * \
+ * \
+ * Arguments: @CTXN_ctx *ctx@ = pointer to a context block \
+ * @const char *encodemap@ = pointer to encoding map \
+ * @const unsigned char *p@ = pointer to a source buffer \
+ * @size_t sz@ = size of the source buffer \
+ * @dstr *d@ = pointer to destination string \
+ * \
+ * Returns: Zero on success, or @CDCERR_@ error code. \
+ * \
+ * Use: Main encoder function. \
+ */ \
+ \
+static int ctxn##_doencode(ctxn##_ctx *ctx, const char *encodemap, \
+ const unsigned char *p, size_t sz, dstr *d) \
+{ \
+ STATE_UNPACK(acc); \
+ const unsigned char *l = p + sz; \
+ unsigned lnlen = ctx->lnlen, maxln = ctx->maxline; \
+ \
+ if (p) { \
+ while (p < l) BASECONV(*p++, 8, wd, PUTWRAP); \
+ } else { \
+ BASECONV_FLUSH(8, wd, PUTWRAP); \
+ if (!(f & CDCF_NOEQPAD)) ctxn##_PADDING(8, wd, PADWRAP); \
+ } \
+ \
+ STATE_PACK(acc); \
+ ctx->lnlen = lnlen; \
+ return (0); \
+} \
+ \
+/* --- @CTXN_dodecode@ --- * \
+ * \
+ * Arguments: @CTXN_ctx *ctx@ = pointer to a context block \
+ * @const signed char *decodemap@ = pointer to decode map \
+ * @const char *p@ = pointer to a source buffer \
+ * @size_t sz@ = size of the source buffer \
+ * @dstr *d@ = pointer to destination string \
+ * \
+ * Returns: Zero on success, or @CDCERR_@ error code. \
+ * \
+ * Use: Main decoder function. \
+ */ \
+ \
+static int ctxn##_dodecode(ctxn##_ctx *ctx, \
+ const signed char *decodemap, \
+ const unsigned char *p, size_t sz, dstr *d) \
+{ \
+ STATE_UNPACK(acc); \
+ const unsigned char *l = p + sz; \
+ int ch; \
+ int x; \
+ \
+ if (p) { \
+ while (p < l) { \
+ ch = *p++; \
+ switch (f & (CDCF_LOWERC | CDCF_IGNCASE)) { \
+ case 0: \
+ break; \
+ case CDCF_LOWERC: \
+ if (isupper(ch)) goto badch; \
+ default: \
+ ch = toupper(ch); \
+ } \
+ x = decodemap[ch]; \
+ switch (x) { \
+ case NV: \
+ badch: \
+ if (!(f & CDCF_IGNINVCH)) return (CDCERR_INVCH); \
+ break; \
+ case PC: \
+ if (f & CDCF_IGNEQMID) break; \
+ if (f & CDCF_NOEQPAD) goto badch; \
+ if (st == ST_MAIN && \
+ !(f & CDCF_IGNZPAD) && (a & ((1 << nb) - 1))) \
+ return (CDCERR_INVZPAD); \
+ st = ST_PAD; \
+ if (!(f & CDCF_IGNEQPAD)) { \
+ if (!nb) return (CDCERR_INVEQPAD); \
+ nb = (nb + wd)%8; \
+ st = ST_PAD; \
+ } \
+ break; \
+ case NL: \
+ if (f & CDCF_IGNNEWL) break; \
+ return (CDCERR_INVCH); \
+ default: \
+ if (st != ST_MAIN) \
+ return (CDCERR_INVEQPAD); \
+ BASECONV(x, wd, 8, PUTRAW); \
+ break; \
+ } \
+ } \
+ } else { \
+ if (st == ST_MAIN && \
+ !(f & CDCF_IGNZPAD) && (a & ((1 << nb) - 1))) \
+ return (CDCERR_INVZPAD); \
+ if (!(f & (CDCF_IGNEQPAD | CDCF_IGNEQMID | CDCF_NOEQPAD)) && nb) \
+ return (CDCERR_INVEQPAD); \
+ } \
+ \
+ STATE_PACK(acc); \
+ return (0); \
+}
+
+CTXS(ENCODER)
+
+/*----- Codec implementation ----------------------------------------------*/
+
+#define OPS(ctxn, wd, acc) \
+ \
+static int ctxn##_enc(codec *c, const void *p, size_t sz, dstr *d) \
+{ \
+ ctxn##_codec *bc = (ctxn##_codec *)c; \
+ return (ctxn##_doencode(&bc->ctx, bc->encodemap, p, sz, d)); \
+} \
+ \
+static int ctxn##_dec(codec *c, const void *p, size_t sz, dstr *d) \
+{ \
+ ctxn##_codec *bc = (ctxn##_codec *)c; \
+ return (ctxn##_dodecode(&bc->ctx, bc->decodemap, p, sz, d)); \
+} \
+ \
+static void ctxn##_destroy(codec *c) \
+{ \
+ ctxn##_codec *bc = (ctxn##_codec *)c; \
+ if (bc->ctx.indent) xfree((/*unconst*/ char *)bc->ctx.indent); \
+ DESTROY(bc); \
+} \
+ \
+static codec *ctxn##_docreate(unsigned flags, \
+ const char *indent, unsigned maxline, \
+ const codec_ops *ops, \
+ const char *encodemap, \
+ const signed char *decodemap) \
+{ \
+ ctxn##_codec *bc = CREATE(ctxn##_codec); \
+ bc->c.ops = ops; \
+ bc->ctx.acc = 0; \
+ bc->ctx.qsz = (flags & ctxn##_FLAGMASK) ^ ctxn##_FLAGXOR; \
+ bc->ctx.lnlen = 0; \
+ bc->ctx.indent = indent ? xstrdup(indent) : 0; \
+ bc->ctx.maxline = maxline; \
+ bc->encodemap = encodemap; \
+ bc->decodemap = decodemap; \
+ return (&bc->c); \
+}
+
+CTXS(OPS)
+
+#define CLASS(name, ctxn, acc) \
+ \
+static const codec_ops \
+ name##_encode_ops = { &name##_class, ctxn##_enc, ctxn##_destroy }, \
+ name##_decode_ops = { &name##_class, ctxn##_dec, ctxn##_destroy }; \
+ \
+static codec *name##_encoder(unsigned flags, \
+ const char *indent, unsigned maxline) \
+{ \
+ return ctxn##_docreate(flags, indent, maxline, \
+ &name##_encode_ops, \
+ encodemap_##name, \
+ decodemap_##name); \
+} \
+ \
+static codec *name##_decoder(unsigned flags) \
+{ \
+ return ctxn##_docreate(flags, 0, 0, \
+ &name##_decode_ops, \
+ encodemap_##name, \
+ decodemap_##name); \
+} \
+ \
+const codec_class name##_class = \
+ { #name, name##_encoder, name##_decoder };
+
+CODECS(CLASS)
+
+/*----- Compatibility veneers ---------------------------------------------*/
+
+#define COMPAT(ctxn, wd, acc) \
+ \
+void ctxn##_encode(ctxn##_ctx *ctx, const void *p, size_t sz, dstr *d) \
+ { ctxn##_doencode(ctx, encodemap_##ctxn, p, sz, d); } \
+ \
+void ctxn##_decode(ctxn##_ctx *ctx, const void *p, size_t sz, dstr *d) \
+ { ctxn##_dodecode(ctx, decodemap_##ctxn, p, sz, d); } \
+ \
+void ctxn##_init(ctxn##_ctx *ctx) \
+{ \
+ ctx->acc = 0; \
+ ctx->qsz = (ctxn##_OLDFLAGS & ctxn##_FLAGMASK) ^ ctxn##_FLAGXOR; \
+ ctx->lnlen = 0; \
+ ctx->indent = "\n"; \
+ ctx->maxline = 72; \
+}
+
+CTXS(COMPAT)
+
+/*----- That's all, folks -------------------------------------------------*/
~mdw / mLib / blobdiff