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34 #include <krb5_locl.h>
36 RCSID("$Id: rd_safe.c,v 1.27 2002/09/04 16:26:05 joda Exp $");
38 static krb5_error_code
39 verify_checksum(krb5_context context,
40 krb5_auth_context auth_context,
52 safe->cksum.cksumtype = 0;
53 safe->cksum.checksum.data = NULL;
54 safe->cksum.checksum.length = 0;
56 ASN1_MALLOC_ENCODE(KRB_SAFE, buf, buf_size, safe, &len, ret);
60 krb5_abortx(context, "internal error in ASN.1 encoder");
62 if (auth_context->remote_subkey)
63 key = auth_context->remote_subkey;
64 else if (auth_context->local_subkey)
65 key = auth_context->local_subkey;
67 key = auth_context->keyblock;
69 ret = krb5_crypto_init(context, key, 0, &crypto);
72 ret = krb5_verify_checksum (context,
74 KRB5_KU_KRB_SAFE_CKSUM,
78 krb5_crypto_destroy(context, crypto);
86 krb5_rd_safe(krb5_context context,
87 krb5_auth_context auth_context,
88 const krb5_data *inbuf,
90 /*krb5_replay_data*/ void *outdata)
96 ret = decode_KRB_SAFE (inbuf->data, inbuf->length, &safe, &len);
100 ret = KRB5KRB_AP_ERR_BADVERSION;
101 krb5_clear_error_string (context);
104 if (safe.msg_type != krb_safe) {
105 ret = KRB5KRB_AP_ERR_MSG_TYPE;
106 krb5_clear_error_string (context);
109 if (!krb5_checksum_is_keyed(context, safe.cksum.cksumtype)
110 || !krb5_checksum_is_collision_proof(context, safe.cksum.cksumtype)) {
111 ret = KRB5KRB_AP_ERR_INAPP_CKSUM;
112 krb5_clear_error_string (context);
116 /* check sender address */
118 if (safe.safe_body.s_address
119 && auth_context->remote_address
120 && !krb5_address_compare (context,
121 auth_context->remote_address,
122 safe.safe_body.s_address)) {
123 ret = KRB5KRB_AP_ERR_BADADDR;
124 krb5_clear_error_string (context);
128 /* check receiver address */
130 if (safe.safe_body.r_address
131 && auth_context->local_address
132 && !krb5_address_compare (context,
133 auth_context->local_address,
134 safe.safe_body.r_address)) {
135 ret = KRB5KRB_AP_ERR_BADADDR;
136 krb5_clear_error_string (context);
140 /* check timestamp */
141 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
144 krb5_timeofday (context, &sec);
146 if (safe.safe_body.timestamp == NULL ||
147 safe.safe_body.usec == NULL ||
148 abs(*safe.safe_body.timestamp - sec) > context->max_skew) {
149 ret = KRB5KRB_AP_ERR_SKEW;
150 krb5_clear_error_string (context);
154 /* XXX - check replay cache */
156 /* check sequence number. since MIT krb5 cannot generate a sequence
157 number of zero but instead generates no sequence number, we accept that
160 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
161 if ((safe.safe_body.seq_number == NULL
162 && auth_context->remote_seqnumber != 0)
163 || (safe.safe_body.seq_number != NULL
164 && *safe.safe_body.seq_number !=
165 auth_context->remote_seqnumber)) {
166 ret = KRB5KRB_AP_ERR_BADORDER;
167 krb5_clear_error_string (context);
170 auth_context->remote_seqnumber++;
173 ret = verify_checksum (context, auth_context, &safe);
177 outbuf->length = safe.safe_body.user_data.length;
178 outbuf->data = malloc(outbuf->length);
179 if (outbuf->data == NULL) {
181 krb5_set_error_string (context, "malloc: out of memory");
184 memcpy (outbuf->data, safe.safe_body.user_data.data, outbuf->length);
185 free_KRB_SAFE (&safe);
188 free_KRB_SAFE (&safe);