X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/c3caa2face1cda7002eb58245ad75865bf437455..e74e12bc7c899a47d3f0e28420f6502b8f70a5a9:/buf.c diff --git a/buf.c b/buf.c index 5e0a069..0cf2cf0 100644 --- a/buf.c +++ b/buf.c @@ -1,13 +1,13 @@ /* -*-c-*- * - * $Id: buf.c,v 1.2 2003/11/10 22:18:30 mdw Exp $ + * $Id$ * * Buffer handling * * (c) 2001 Straylight/Edgeware */ -/*----- Licensing notice --------------------------------------------------* +/*----- Licensing notice --------------------------------------------------* * * This file is part of Catacomb. * @@ -15,301 +15,114 @@ * 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. - * + * * Catacomb 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 Catacomb; if not, write to the Free * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, * MA 02111-1307, USA. */ -/*----- Revision history --------------------------------------------------* - * - * $Log: buf.c,v $ - * Revision 1.2 2003/11/10 22:18:30 mdw - * Build fixes. - * - * Revision 1.1 2003/10/11 21:02:33 mdw - * Import buf stuff from tripe. - * - * Revision 1.4 2001/06/19 22:09:54 mdw - * Expose interface, for use in the proxy. - * - * Revision 1.3 2001/03/03 12:06:48 mdw - * Use 16-bit lengths on MPs, since there's a packet limit of 64K anyway. - * - * Revision 1.2 2001/02/16 21:23:20 mdw - * Various minor changes. Check that MPs are in canonical form when - * loading. - * - * Revision 1.1 2001/02/03 20:26:37 mdw - * Initial checkin. - * - */ - /*----- Header files ------------------------------------------------------*/ #include #include "mp.h" +#include "ec.h" #include "buf.h" /*----- Main code ---------------------------------------------------------*/ -/* --- @buf_init@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @void *p@ = pointer to a buffer - * @size_t sz@ = size of the buffer - * - * Returns: --- - * - * Use: Initializes the buffer block appropriately. - */ - -void buf_init(buf *b, void *p, size_t sz) -{ - b->base = b->p = p; - b->limit = b->p + sz; - b->f = 0; -} - -/* --- @buf_break@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * - * Returns: Some negative value. - * - * Use: Marks a buffer as broken. - */ - -int buf_break(buf *b) { b->f |= BF_BROKEN; return (-1); } - -/* --- @buf_flip@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * - * Returns: --- - * - * Use: Flips a buffer so that if you've just been writing to it, - * you can now read from the bit you've written. - */ - -void buf_flip(buf *b) -{ - b->limit = b->p; - b->p = b->base; -} - -/* --- @buf_ensure@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @size_t sz@ = size of data wanted - * - * Returns: Zero if it worked, nonzero if there wasn't enough space. - * - * Use: Ensures that there are @sz@ bytes still in the buffer. - */ - -int buf_ensure(buf *b, size_t sz) { return (BENSURE(b, sz)); } - -/* --- @buf_get@ --- * +/* --- @buf_getmp@ --- * * * Arguments: @buf *b@ = pointer to a buffer block - * @size_t sz@ = size of the buffer * - * Returns: Pointer to the place in the buffer. + * Returns: A multiprecision integer, or null if there wasn't one there. * - * Use: Reserves a space in the buffer of the requested size, and - * returns its start address. + * Use: Gets a multiprecision integer from a buffer. */ -void *buf_get(buf *b, size_t sz) +mp *buf_getmp(buf *b) { - void *p; - if (BENSURE(b, sz)) + uint16 sz; + size_t n; + mp *m; + if (buf_getu16(b, &sz) || buf_ensure(b, sz)) + return (0); + m = mp_loadb(MP_NEW, BCUR(b), sz); + n = mp_octets(m); + if (n != sz && n != 0 && sz != 1) { + mp_drop(m); return (0); - p = BCUR(b); + } BSTEP(b, sz); - return (p); + return (m); } -/* --- @buf_put@ --- * +/* --- @buf_putmp@ --- * * * Arguments: @buf *b@ = pointer to a buffer block - * @const void *p@ = pointer to a buffer - * @size_t sz@ = size of the buffer + * @mp *m@ = a multiprecision integer * * Returns: Zero if it worked, nonzero if there wasn't enough space. * - * Use: Fetches data from some place and puts it in the buffer + * Use: Puts a multiprecision integer to a buffer. */ -int buf_put(buf *b, const void *p, size_t sz) +int buf_putmp(buf *b, mp *m) { - if (BENSURE(b, sz)) + size_t sz = mp_octets(m); + assert(sz < MASK16); + if (!sz) sz = 1; + if (buf_putu16(b, sz) || buf_ensure(b, sz)) return (-1); - memcpy(BCUR(b), p, sz); + mp_storeb(m, BCUR(b), sz); BSTEP(b, sz); return (0); } -/* --- @buf_getbyte@ --- * +/* --- @buf_getec@ --- * * * Arguments: @buf *b@ = pointer to a buffer block + * @ec *p@ = where to put the point * - * Returns: A byte, or less than zero if there wasn't a byte there. + * Returns: Zero if it worked, nonzero if it failed. * - * Use: Gets a single byte from a buffer. + * Use: Gets a multiprecision integer from a buffer. The point must + * be initialized. */ -int buf_getbyte(buf *b) +int buf_getec(buf *b, ec *p) { - if (BENSURE(b, 1)) - return (-1); - return (*b->p++); -} - -/* --- @buf_putbyte@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @int ch@ = byte to write - * - * Returns: Zero if OK, nonzero if there wasn't enough space. - * - * Use: Puts a single byte in a buffer. - */ - -int buf_putbyte(buf *b, int ch) -{ - if (BENSURE(b, 1)) - return (-1); - *b->p++ = ch; - return (0); -} - -/* --- @buf_getu16@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @uint16 *w@ = where to put the word - * - * Returns: Zero if OK, or nonzero if there wasn't a word there. - * - * Use: Gets a 16-bit word from a buffer. - */ - -int buf_getu16(buf *b, uint16 *w) -{ - if (BENSURE(b, 2)) - return (-1); - *w = LOAD16(b->p); - BSTEP(b, 2); - return (0); -} - -/* --- @buf_putu16@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @uint16 w@ = word to write - * - * Returns: Zero if OK, nonzero if there wasn't enough space. - * - * Use: Puts a 16-but word in a buffer. - */ - -int buf_putu16(buf *b, uint16 w) -{ - if (BENSURE(b, 2)) - return (-1); - STORE16(b->p, w); - BSTEP(b, 2); - return (0); -} - -/* --- @buf_getu32@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @uint32 *w@ = where to put the word - * - * Returns: Zero if OK, or nonzero if there wasn't a word there. - * - * Use: Gets a 32-bit word from a buffer. - */ - -int buf_getu32(buf *b, uint32 *w) -{ - if (BENSURE(b, 4)) - return (-1); - *w = LOAD32(b->p); - BSTEP(b, 4); - return (0); -} - -/* --- @buf_putu32@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * @uint32 w@ = word to write - * - * Returns: Zero if OK, nonzero if there wasn't enough space. - * - * Use: Puts a 32-but word in a buffer. - */ - -int buf_putu32(buf *b, uint32 w) -{ - if (BENSURE(b, 4)) - return (-1); - STORE32(b->p, w); - BSTEP(b, 4); - return (0); -} - -/* --- @buf_getmp@ --- * - * - * Arguments: @buf *b@ = pointer to a buffer block - * - * Returns: A multiprecision integer, or null if there wasn't one there. - * - * Use: Gets a multiprecision integer from a buffer. - */ - -mp *buf_getmp(buf *b) -{ - uint16 sz; - mp *m; - if (buf_getu16(b, &sz) || buf_ensure(b, sz)) - return (0); - m = mp_loadb(MP_NEW, BCUR(b), sz); - if (mp_octets(m) != sz) { - mp_drop(m); - return (0); + mp *x = 0, *y = 0; + uint16 n; + if (buf_ensure(b, 2)) return (-1); + n = LOAD16(BCUR(b)); if (!n) { BSTEP(b, 2); EC_SETINF(p); return (0); } + if ((x = buf_getmp(b)) == 0 || (y = buf_getmp(b)) == 0) { + mp_drop(x); mp_drop(y); return (-1); } - BSTEP(b, sz); - return (m); + EC_DESTROY(p); p->x = x; p->y = y; p->z = 0; + return (0); } -/* --- @buf_putmp@ --- * +/* --- @buf_putec@ --- * * * Arguments: @buf *b@ = pointer to a buffer block - * @mp *m@ = a multiprecision integer + * @ec *p@ = an elliptic curve point * * Returns: Zero if it worked, nonzero if there wasn't enough space. * - * Use: Puts a multiprecision integer to a buffer. + * Use: Puts an elliptic curve point to a buffer. */ -int buf_putmp(buf *b, mp *m) +int buf_putec(buf *b, ec *p) { - size_t sz = mp_octets(m); - assert(sz < MASK16); - if (buf_putu16(b, sz) || buf_ensure(b, sz)) - return (-1); - mp_storeb(m, BCUR(b), sz); - BSTEP(b, sz); + if (EC_ATINF(p)) return (buf_putu16(b, 0)); + if (buf_putmp(b, p->x) || buf_putmp(b, p->y)) return (-1); return (0); }