X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/0d4a06cd790bcad456592d60cb4b40981fa2429a..3563e36580c7dad68cd6d3f7eb82eef570fc0c76:/key-binary.c diff --git a/key-binary.c b/key-binary.c index 79712e1..82a1ecb 100644 --- a/key-binary.c +++ b/key-binary.c @@ -1,6 +1,6 @@ /* -*-c-*- * - * $Id: key-binary.c,v 1.3 2001/02/03 11:57:00 mdw Exp $ + * $Id: key-binary.c,v 1.5 2004/04/01 12:50:09 mdw Exp $ * * Key binary encoding * @@ -30,6 +30,16 @@ /*----- Revision history --------------------------------------------------* * * $Log: key-binary.c,v $ + * Revision 1.5 2004/04/01 12:50:09 mdw + * Add cyclic group abstraction, with test code. Separate off exponentation + * functions for better static linking. Fix a buttload of bugs on the way. + * Generally ensure that negative exponents do inversion correctly. Add + * table of standard prime-field subgroups. (Binary field subgroups are + * currently unimplemented but easy to add if anyone ever finds a good one.) + * + * Revision 1.4 2004/03/28 01:58:47 mdw + * Generate, store and retreive elliptic curve keys. + * * Revision 1.3 2001/02/03 11:57:00 mdw * Track mLib change: symbols no longer need to include a terminating * null. @@ -107,6 +117,29 @@ int key_decode(const void *p, size_t sz, key_data *k) k->u.m = mp_loadb(k->e & KF_BURN ? MP_NEWSEC : MP_NEW, q + 4, psz); break; + /* --- String data --- */ + + case KENC_STRING: + k->u.p = xmalloc(sz + 1); + memcpy(k->u.p, q + 4, sz); + k->u.p[sz] = 0; + break; + + /* --- Elliptic curve point data --- */ + + case KENC_EC: { + size_t xsz, ysz; + EC_CREATE(&k->u.e); + if (!sz) break; + if (sz < 2) return (-1); + xsz = LOAD16(q + 4); + if (sz < xsz + 4) return (-1); + ysz = LOAD16(q + 6 + xsz); + if (sz < xsz + ysz + 4) return (-1); + k->u.e.x = mp_loadb(MP_NEW, q + 6, xsz); + k->u.e.y = mp_loadb(MP_NEW, q + 6 + xsz, ysz); + } break; + /* --- Structured key data --- */ case KENC_STRUCT: { @@ -216,6 +249,45 @@ int key_encode(key_data *k, dstr *d, const key_filter *kf) rc = 1; } break; + case KENC_STRING: { + char *p; + size_t sz = strlen(k->u.p); + + DENSURE(d, (sz + 7) & ~3); + p = d->buf + d->len; + STORE16(p, k->e); + STORE16(p + 2, sz); + memcpy(p + 4, k->u.p, sz); + d->len += sz + 4; + rc = 1; + } break; + + case KENC_EC: { + char *p; + size_t xsz, ysz; + size_t sz; + + if (EC_ATINF(&k->u.e)) + sz = 0; + else { + xsz = mp_octets(k->u.e.x); + ysz = mp_octets(k->u.e.y); + sz = xsz + ysz + 4; + } + DENSURE(d, (sz + 7) & ~3); + p = d->buf + d->len; + STORE16(p, k->e); + STORE16(p + 2, sz); + if (!EC_ATINF(&k->u.e)) { + STORE16(p + 4, xsz); + mp_storeb(k->u.e.x, p + 6, xsz); + STORE16(p + 6 + xsz, ysz); + mp_storeb(k->u.e.y, p + 8 + xsz, ysz); + } + d->len += sz + 4; + rc = 1; + } break; + case KENC_STRUCT: { size_t n; char *p;