2 * Common routines for ASN.1
5 * Wireshark - Network traffic analyzer
6 * By Gerald Combs <gerald@wireshark.org>
7 * Copyright 1998 Gerald Combs
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version 2
12 * of the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
35 #include <epan/packet.h>
39 void asn1_ctx_init(asn1_ctx_t *actx, asn1_enc_e encoding, gboolean aligned, packet_info *pinfo) {
40 memset(actx, '\0', sizeof(*actx));
41 actx->signature = ASN1_CTX_SIGNATURE;
42 actx->encoding = encoding;
43 actx->aligned = aligned;
47 gboolean asn1_ctx_check_signature(asn1_ctx_t *actx) {
48 return actx && (actx->signature == ASN1_CTX_SIGNATURE);
51 void asn1_ctx_clean_external(asn1_ctx_t *actx) {
52 memset(&actx->external, '\0', sizeof(actx->external));
53 actx->external.hf_index = -1;
54 actx->external.encoding = -1;
57 void asn1_ctx_clean_epdv(asn1_ctx_t *actx) {
58 memset(&actx->embedded_pdv, '\0', sizeof(actx->embedded_pdv));
59 actx->embedded_pdv.hf_index = -1;
60 actx->embedded_pdv.identification = -1;
64 /*--- stack/parameters ---*/
66 void asn1_stack_frame_push(asn1_ctx_t *actx, const gchar *name) {
67 asn1_stack_frame_t *frame;
69 frame = wmem_new0(wmem_packet_scope(), asn1_stack_frame_t);
71 frame->next = actx->stack;
75 void asn1_stack_frame_pop(asn1_ctx_t *actx, const gchar *name) {
76 DISSECTOR_ASSERT(actx->stack);
77 DISSECTOR_ASSERT(!strcmp(actx->stack->name, name));
78 actx->stack = actx->stack->next;
81 void asn1_stack_frame_check(asn1_ctx_t *actx, const gchar *name, const asn1_par_def_t *par_def) {
82 const asn1_par_def_t *pd = par_def;
85 DISSECTOR_ASSERT(actx->stack);
86 DISSECTOR_ASSERT(!strcmp(actx->stack->name, name));
88 par = actx->stack->par;
90 DISSECTOR_ASSERT(par);
91 DISSECTOR_ASSERT((pd->ptype == ASN1_PAR_IRR) || (par->ptype == pd->ptype));
96 DISSECTOR_ASSERT(!par);
99 static asn1_par_t *get_par_by_name(asn1_ctx_t *actx, const gchar *name) {
100 asn1_par_t *par = NULL;
102 DISSECTOR_ASSERT(actx->stack);
103 par = actx->stack->par;
105 if (!strcmp(par->name, name))
112 static asn1_par_t *push_new_par(asn1_ctx_t *actx) {
113 asn1_par_t *par, **pp;
115 DISSECTOR_ASSERT(actx->stack);
117 par = wmem_new0(wmem_packet_scope(), asn1_par_t);
119 pp = &(actx->stack->par);
127 void asn1_param_push_boolean(asn1_ctx_t *actx, gboolean value) {
130 par = push_new_par(actx);
131 par->ptype = ASN1_PAR_BOOLEAN;
132 par->value.v_boolean = value;
135 void asn1_param_push_integer(asn1_ctx_t *actx, gint32 value) {
138 par = push_new_par(actx);
139 par->ptype = ASN1_PAR_INTEGER;
140 par->value.v_integer = value;
143 gboolean asn1_param_get_boolean(asn1_ctx_t *actx, const gchar *name) {
144 asn1_par_t *par = NULL;
146 par = get_par_by_name(actx, name);
147 DISSECTOR_ASSERT(par);
148 return par->value.v_boolean;
151 gint32 asn1_param_get_integer(asn1_ctx_t *actx, const gchar *name) {
152 asn1_par_t *par = NULL;
154 par = get_par_by_name(actx, name);
155 DISSECTOR_ASSERT(par);
156 return par->value.v_integer;
162 void rose_ctx_init(rose_ctx_t *rctx) {
163 memset(rctx, '\0', sizeof(*rctx));
164 rctx->signature = ROSE_CTX_SIGNATURE;
167 gboolean rose_ctx_check_signature(rose_ctx_t *rctx) {
168 return rctx && (rctx->signature == ROSE_CTX_SIGNATURE);
171 void rose_ctx_clean_data(rose_ctx_t *rctx) {
172 memset(&rctx->d, '\0', sizeof(rctx->d));
176 asn1_ctx_t *get_asn1_ctx(void *ptr) {
177 asn1_ctx_t *actx = (asn1_ctx_t*)ptr;
179 if (!asn1_ctx_check_signature(actx))
185 rose_ctx_t *get_rose_ctx(void *ptr) {
186 rose_ctx_t *rctx = (rose_ctx_t*)ptr;
187 asn1_ctx_t *actx = (asn1_ctx_t*)ptr;
189 if (!asn1_ctx_check_signature(actx))
193 rctx = actx->rose_ctx;
195 if (!rose_ctx_check_signature(rctx))
201 /** Only tested for BER */
202 double asn1_get_real(const guint8 *real_ptr, gint len) {
208 /* 8.5.2 If the real value is the value zero,
209 * there shall be no contents octets in the encoding.
211 if (len < 1) return val;
216 if (octet & 0x80) { /* binary encoding */
221 guint8 F; /* scaling Factor */
222 gint32 E = 0; /* Exponent (supported max 3 octets/24 bit) */
223 guint64 N = 0; /* N (supported max 8 octets/64 bit) */
227 if(octet & 0x40) S = -1; else S = 1;
228 switch(octet & 0x30) {
229 case 0x00: B = 2; break;
230 case 0x10: B = 8; break;
231 case 0x20: B = 16; break;
232 case 0x30: /* Reserved */
234 /* TODO Add some warning in tree about reserved value for Base */
237 F = (octet & 0x0c) >> 2;
239 /* 8.5.6.4 Exponent length */
240 lenE = (octet & 0x3) + 1;
243 /* we can't handle exponents > 24 bits */
244 /* TODO Next octet(s) define length of exponent */
245 DISSECTOR_ASSERT_NOT_REACHED();
248 Eneg = (*p) & 0x80 ? TRUE : FALSE;
249 for (i = 0; i < lenE; i++) {
251 /* 2's complement: inverse bits */
252 E = (E<<8) | ((guint8) ~(*p));
259 /* 2's complement: ... and add 1 (and make negative of course) */
266 /* we can't handle integers > 64 bits */
267 DISSECTOR_ASSERT_NOT_REACHED();
269 for (i=0; i<lenN; i++) {
273 val = (double) S * N * pow(2, F) * pow(B, E);
275 printf("S = %d, N = %lu, F = %u, B = %u, E = %d -> %f\n", S, N, F, B, E, val);
277 } else if (octet & 0x40) { /* SpecialRealValue */
278 switch (octet & 0x3F) {
279 case 0x00: val = HUGE_VAL; break;
280 case 0x01: val = -HUGE_VAL; break;
282 } else { /* decimal encoding */
283 buf = g_strndup(p, len);
284 val = g_ascii_strtod(buf, NULL);
292 * Editor modelines - http://www.wireshark.org/tools/modelines.html
297 * indent-tabs-mode: nil
300 * ex: set shiftwidth=2 tabstop=8 expandtab:
301 * :indentSize=2:tabSize=8:noTabs=true: