/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * GXSNMP -- An snmp mangament application * * This code implements the MD2 message-digest algorithm. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include "gxsnmp_hash.h" #include "gxsnmp_md2.h" /* Permutation of 0..255 constructed from the digits of pi. It gives a "random" nonlinear byte substitution operation. */ static guchar PI_SUBST[256] = { 41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6, 19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188, 76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24, 138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251, 245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63, 148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50, 39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165, 181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210, 150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157, 112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27, 96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15, 85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197, 234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65, 129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123, 8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233, 203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228, 166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237, 31, 26, 219, 153, 141, 51, 159, 17, 131, 20 }; static guchar *PADDING[] = { (guchar *)"", (guchar *)"\001", (guchar *)"\002\002", (guchar *)"\003\003\003", (guchar *)"\004\004\004\004", (guchar *)"\005\005\005\005\005", (guchar *)"\006\006\006\006\006\006", (guchar *)"\007\007\007\007\007\007\007", (guchar *)"\010\010\010\010\010\010\010\010", (guchar *)"\011\011\011\011\011\011\011\011\011", (guchar *)"\012\012\012\012\012\012\012\012\012\012", (guchar *)"\013\013\013\013\013\013\013\013\013\013\013", (guchar *)"\014\014\014\014\014\014\014\014\014\014\014\014", (guchar *)"\015\015\015\015\015\015\015\015\015\015\015\015\015", (guchar *)"\016\016\016\016\016\016\016\016\016\016\016\016\016\016", (guchar *)"\017\017\017\017\017\017\017\017\017\017\017\017\017\017\017", (guchar *)"\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020" }; static void MD2Init(GxsnmpMd2 *md2); static void MD2Transform(guchar state[16], guchar checksum[16], guchar block[16]); static void gxsnmp_md2_init (GxsnmpMd2 *md2); static void gxsnmp_md2_class_init (GxsnmpMd2Class *klass); static void gxsnmp_md2_finalize (GObject *object); static void gxsnmp_md2_update (GxsnmpHash *hash, guchar const *buf, guint len); static void gxsnmp_md2_final (GxsnmpHash *hash, guchar *buf); static void gxsnmp_md2_reset (GxsnmpHash *hash); static gpointer parent_class = NULL; GType gxsnmp_md2_get_type (void) { static GType object_type = 0; if (!object_type) { static const GTypeInfo object_info = { sizeof (GxsnmpMd2Class), (GBaseInitFunc) NULL, (GBaseFinalizeFunc) NULL, (GClassInitFunc) gxsnmp_md2_class_init, NULL, /* class_finalize */ NULL, /* class_data */ sizeof (GxsnmpMd2), 0, /* n_preallocs */ (GInstanceInitFunc) gxsnmp_md2_init, }; object_type = g_type_register_static (gxsnmp_hash_get_type(), "GxsnmpMd2", &object_info, 0); } return object_type; } static void gxsnmp_md2_init (GxsnmpMd2 *object) { GxsnmpHash *hash = GXSNMP_HASH(object); hash->result = g_malloc(16); hash->hashlen = 16; hash->hashname = "MD2"; if (hash->result) MD2Init(object); } static void gxsnmp_md2_class_init (GxsnmpMd2Class *klass) { GObjectClass *object_class = G_OBJECT_CLASS (klass); GxsnmpHashClass *hash_class = GXSNMP_HASH_CLASS (klass); parent_class = g_type_class_peek_parent (klass); hash_class->update = gxsnmp_md2_update; hash_class->final = gxsnmp_md2_final; hash_class->reset = gxsnmp_md2_reset; object_class->finalize = gxsnmp_md2_finalize; } static void gxsnmp_md2_finalize (GObject *object) { G_OBJECT_CLASS (parent_class)->finalize (object); } static void gxsnmp_md2_reset (GxsnmpHash *hash) { GxsnmpMd2 *md2; md2 = GXSNMP_MD2(hash); if (hash->result) MD2Init(md2); } static void gxsnmp_md2_update (GxsnmpHash *hash, guchar const *buf, guint len) { GxsnmpMd2 *md2; guint i, index, partLen; md2 = GXSNMP_MD2(hash); /* Update number of bytes mod 16 */ index = md2->count; md2->count = (index + len) & 0xf; partLen = 16 - index; /* Transform as many times as possible. */ if (len >= partLen) { g_memmove (&md2->data[index], buf, partLen); MD2Transform ((guchar *)hash->result, md2->checksum, md2->data); for (i = partLen; i + 15 < len; i += 16) MD2Transform ((guchar *)hash->result, md2->checksum, (guchar *)&buf[i]); index = 0; } else i = 0; /* Buffer remaining input */ g_memmove (&md2->data[index], &buf[i], len-i); } static void gxsnmp_md2_final (GxsnmpHash *hash, guchar *buf) { guint index, padLen; GxsnmpMd2 *md2; md2 = GXSNMP_MD2(hash); /* Pad out to multiple of 16. */ index = md2->count; padLen = 16 - index; gxsnmp_md2_update (hash, PADDING[padLen], padLen); /* Extend with checksum */ gxsnmp_md2_update (hash, md2->checksum, 16); /* Store state in digest */ g_memmove (buf, hash->result, 16); /* Zeroize sensitive information. */ memset (hash->result, 0, hash->hashlen); memset (md2->checksum, 0, 16); memset (md2->data, 0, 16); } /* * Start MD2 accumulation. Set bit count to 0 and buffer to mysterious * initialization constants. */ static void MD2Init(GxsnmpMd2 *object) { GxsnmpHash *hash = GXSNMP_HASH(object); object->count = 0; memset(object->checksum, 0, 16); memset(hash->result, 0, 16); } static void MD2Transform(guchar state[16], guchar checksum[16], guchar block[16]) { guint i, j, t; guchar x[48]; /* Form encryption block from state, block, state ^ block. */ g_memmove(x, state, 16); g_memmove(x+16, block, 16); for (i = 0; i < 16; i++) x[i+32] = state[i] ^ block[i]; /* Encrypt block (18 rounds). */ t = 0; for (i = 0; i < 18; i++) { for (j = 0; j < 48; j++) t = x[j] ^= PI_SUBST[t]; t = (t + i) & 0xff; } /* Save new state */ g_memmove(state, x, 16); /* Update checksum. */ t = checksum[15]; for (i = 0; i < 16; i++) t = checksum[i] ^= PI_SUBST[block[i] ^ t]; /* Zeroize sensitive information. */ memset(x, 0, sizeof (x)); } GxsnmpMd2* gxsnmp_md2_new() { GxsnmpMd2* md2; md2 = g_object_new (gxsnmp_md2_get_type (), NULL); return md2; }