diff options
Diffstat (limited to '')
| -rw-r--r-- | dirmngr/b64enc.c | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/dirmngr/b64enc.c b/dirmngr/b64enc.c new file mode 100644 index 000000000..4429a8e75 --- /dev/null +++ b/dirmngr/b64enc.c @@ -0,0 +1,213 @@ +/* b64enc.c - Simple Base64 encoder. + * Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc. + * + * This file is part of GnuPG. + * + * GnuPG is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * GnuPG 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA + */ + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <assert.h> + +#include "i18n.h" +#include "util.h" + +#define B64ENC_DID_HEADER 1 +#define B64ENC_DID_TRAILER 2 +#define B64ENC_NO_LINEFEEDS 16 + + +/* The base-64 character list */ +static unsigned char bintoasc[64] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "abcdefghijklmnopqrstuvwxyz" + "0123456789+/"; + +/* Prepare for base-64 writing to the stream FP. If TITLE is not NULL + and not an empty string, this string will be used as the title for + the armor lines, with TITLE being an empty string, we don't write + the header lines and furthermore even don't write any linefeeds. + With TITLE beeing NULL, we merely don't write header but make sure + that lines are not too long. Note, that we don't write any output + unless at least one byte get written using b64enc_write. */ +gpg_error_t +b64enc_start (struct b64state *state, FILE *fp, const char *title) +{ + memset (state, 0, sizeof *state); + state->fp = fp; + if (title && !*title) + state->flags |= B64ENC_NO_LINEFEEDS; + else if (title) + { + state->title = strdup (title); + if (!state->title) + return gpg_error_from_errno (errno); + } + return 0; +} + + +/* Write NBYTES from BUFFER to the Base 64 stream identified by + STATE. With BUFFER and NBYTES being 0, merely do a fflush on the + stream. */ +gpg_error_t +b64enc_write (struct b64state *state, const void *buffer, size_t nbytes) +{ + unsigned char radbuf[4]; + int idx, quad_count; + const unsigned char *p; + FILE *fp = state->fp; + + + if (!nbytes) + { + if (buffer && fflush (fp)) + goto write_error; + return 0; + } + + if (!(state->flags & B64ENC_DID_HEADER)) + { + if (state->title) + { + if ( fputs ("-----BEGIN ", fp) == EOF + || fputs (state->title, fp) == EOF + || fputs ("-----\n", fp) == EOF) + goto write_error; + } + state->flags |= B64ENC_DID_HEADER; + } + + idx = state->idx; + quad_count = state->quad_count; + assert (idx < 4); + memcpy (radbuf, state->radbuf, idx); + + for (p=buffer; nbytes; p++, nbytes--) + { + radbuf[idx++] = *p; + if (idx > 2) + { + char tmp[4]; + + tmp[0] = bintoasc[(*radbuf >> 2) & 077]; + tmp[1] = bintoasc[(((*radbuf<<4)&060)|((radbuf[1] >> 4)&017))&077]; + tmp[2] = bintoasc[(((radbuf[1]<<2)&074)|((radbuf[2]>>6)&03))&077]; + tmp[3] = bintoasc[radbuf[2]&077]; + for (idx=0; idx < 4; idx++) + putc (tmp[idx], fp); + idx = 0; + if (ferror (fp)) + goto write_error; + if (++quad_count >= (64/4)) + { + quad_count = 0; + if (!(state->flags & B64ENC_NO_LINEFEEDS) + && fputs ("\n", fp) == EOF) + goto write_error; + } + } + } + memcpy (state->radbuf, radbuf, idx); + state->idx = idx; + state->quad_count = quad_count; + return 0; + + write_error: + return gpg_error_from_errno (errno); +} + +gpg_error_t +b64enc_finish (struct b64state *state) +{ + gpg_error_t err = 0; + unsigned char radbuf[4]; + int idx, quad_count; + FILE *fp; + + if (!(state->flags & B64ENC_DID_HEADER)) + goto cleanup; + + /* Flush the base64 encoding */ + fp = state->fp; + idx = state->idx; + quad_count = state->quad_count; + assert (idx < 4); + memcpy (radbuf, state->radbuf, idx); + + if (idx) + { + char tmp[4]; + + tmp[0] = bintoasc[(*radbuf>>2)&077]; + if (idx == 1) + { + tmp[1] = bintoasc[((*radbuf << 4) & 060) & 077]; + tmp[2] = '='; + tmp[3] = '='; + } + else + { + tmp[1] = bintoasc[(((*radbuf<<4)&060)|((radbuf[1]>>4)&017))&077]; + tmp[2] = bintoasc[((radbuf[1] << 2) & 074) & 077]; + tmp[3] = '='; + } + for (idx=0; idx < 4; idx++) + putc (tmp[idx], fp); + idx = 0; + if (ferror (fp)) + goto write_error; + + if (++quad_count >= (64/4)) + { + quad_count = 0; + if (!(state->flags & B64ENC_NO_LINEFEEDS) + && fputs ("\n", fp) == EOF) + goto write_error; + } + } + + /* Finish the last line and write the trailer. */ + if (quad_count + && !(state->flags & B64ENC_NO_LINEFEEDS) + && fputs ("\n", fp) == EOF) + goto write_error; + + if (state->title) + { + if ( fputs ("-----END ", fp) == EOF + || fputs (state->title, fp) == EOF + || fputs ("-----\n", fp) == EOF) + goto write_error; + } + + goto cleanup; + + write_error: + err = gpg_error_from_errno (errno); + + cleanup: + if (state->title) + { + free (state->title); + state->title = NULL; + } + state->fp = NULL; + return err; +} + |