1 /* Copyright (c) 2006-2010, UNINETT AS
2 * Copyright (c) 2010-2012, NORDUnet A/S */
3 /* See LICENSE for licensing information. */
6 #include <sys/inttypes.h>
12 #include <arpa/inet.h>
18 #include <openssl/hmac.h>
19 #include <openssl/rand.h>
21 #define RADLEN(x) ntohs(((uint16_t *)(x))[1])
23 void radmsg_free(struct radmsg *msg) {
25 freetlvlist(msg->attrs);
30 struct radmsg *radmsg_init(uint8_t code, uint8_t id, uint8_t *auth) {
33 msg = malloc(sizeof(struct radmsg));
36 memset(msg, 0, sizeof(struct radmsg));
37 msg->attrs = list_create();
45 memcpy(msg->auth, auth, 16);
46 else if (!RAND_bytes(msg->auth, 16)) {
53 int radmsg_add(struct radmsg *msg, struct tlv *attr) {
54 if (!msg || !msg->attrs)
58 return list_push(msg->attrs, attr);
61 /* returns first tlv of the given type */
62 struct tlv *radmsg_gettype(struct radmsg *msg, uint8_t type) {
63 struct list_node *node;
68 for (node = list_first(msg->attrs); node; node = list_next(node)) {
69 tlv = (struct tlv *)node->data;
76 int _checkmsgauth(unsigned char *rad, uint8_t *authattr, uint8_t *secret) {
77 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
78 static unsigned char first = 1;
79 static HMAC_CTX hmacctx;
81 uint8_t auth[16], hash[EVP_MAX_MD_SIZE];
83 pthread_mutex_lock(&lock);
85 HMAC_CTX_init(&hmacctx);
89 memcpy(auth, authattr, 16);
90 memset(authattr, 0, 16);
92 HMAC_Init_ex(&hmacctx, secret, strlen((char *)secret), EVP_md5(), NULL);
93 HMAC_Update(&hmacctx, rad, RADLEN(rad));
94 HMAC_Final(&hmacctx, hash, &md_len);
95 memcpy(authattr, auth, 16);
97 debug(DBG_WARN, "message auth computation failed");
98 pthread_mutex_unlock(&lock);
102 if (memcmp(auth, hash, 16)) {
103 debug(DBG_WARN, "message authenticator, wrong value");
104 pthread_mutex_unlock(&lock);
108 pthread_mutex_unlock(&lock);
112 int _validauth(unsigned char *rad, unsigned char *reqauth, unsigned char *sec) {
113 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
114 static unsigned char first = 1;
115 static EVP_MD_CTX mdctx;
116 unsigned char hash[EVP_MAX_MD_SIZE];
120 pthread_mutex_lock(&lock);
122 EVP_MD_CTX_init(&mdctx);
128 result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
129 EVP_DigestUpdate(&mdctx, rad, 4) &&
130 EVP_DigestUpdate(&mdctx, reqauth, 16) &&
131 (len <= 20 || EVP_DigestUpdate(&mdctx, rad + 20, len - 20)) &&
132 EVP_DigestUpdate(&mdctx, sec, strlen((char *)sec)) &&
133 EVP_DigestFinal_ex(&mdctx, hash, &len) &&
135 !memcmp(hash, rad + 4, 16));
136 pthread_mutex_unlock(&lock);
140 int _createmessageauth(unsigned char *rad, unsigned char *authattrval, uint8_t *secret) {
141 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
142 static unsigned char first = 1;
143 static HMAC_CTX hmacctx;
149 pthread_mutex_lock(&lock);
151 HMAC_CTX_init(&hmacctx);
155 memset(authattrval, 0, 16);
157 HMAC_Init_ex(&hmacctx, secret, strlen((char *)secret), EVP_md5(), NULL);
158 HMAC_Update(&hmacctx, rad, RADLEN(rad));
159 HMAC_Final(&hmacctx, authattrval, &md_len);
161 debug(DBG_WARN, "message auth computation failed");
162 pthread_mutex_unlock(&lock);
165 pthread_mutex_unlock(&lock);
169 int _radsign(unsigned char *rad, unsigned char *sec) {
170 static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
171 static unsigned char first = 1;
172 static EVP_MD_CTX mdctx;
176 pthread_mutex_lock(&lock);
178 EVP_MD_CTX_init(&mdctx);
182 result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
183 EVP_DigestUpdate(&mdctx, rad, RADLEN(rad)) &&
184 EVP_DigestUpdate(&mdctx, sec, strlen((char *)sec)) &&
185 EVP_DigestFinal_ex(&mdctx, rad + 4, &md_len) &&
187 pthread_mutex_unlock(&lock);
191 uint8_t *radmsg2buf(struct radmsg *msg, uint8_t *secret) {
192 struct list_node *node;
195 uint8_t *buf, *p, *msgauth = NULL;
197 if (!msg || !msg->attrs)
200 for (node = list_first(msg->attrs); node; node = list_next(node))
201 size += 2 + ((struct tlv *)node->data)->l;
211 *(uint16_t *)p = htons(size);
213 memcpy(p, msg->auth, 16);
216 for (node = list_first(msg->attrs); node; node = list_next(node)) {
217 tlv = (struct tlv *)node->data;
220 if (tlv->t == RAD_Attr_Message_Authenticator && secret)
224 if (msgauth && !_createmessageauth(buf, msgauth, secret)) {
229 if ((msg->code == RAD_Access_Accept || msg->code == RAD_Access_Reject || msg->code == RAD_Access_Challenge || msg->code == RAD_Accounting_Response || msg->code == RAD_Accounting_Request) && !_radsign(buf, secret)) {
233 if (msg->code == RAD_Accounting_Request)
234 memcpy(msg->auth, buf + 4, 16);
239 /* if secret set we also validate message authenticator if present */
240 struct radmsg *buf2radmsg(uint8_t *buf, uint8_t *secret, uint8_t *rqauth) {
242 uint8_t t, l, *v = NULL, *p, auth[16];
250 if (secret && buf[0] == RAD_Accounting_Request) {
252 if (!_validauth(buf, auth, secret)) {
253 debug(DBG_WARN, "buf2radmsg: Accounting-Request message authentication failed");
258 if (rqauth && !_validauth(buf, rqauth, secret)) {
259 debug(DBG_WARN, "buf2radmsg: Invalid auth, ignoring reply");
263 msg = radmsg_init(buf[0], buf[1], (uint8_t *)buf + 4);
268 while (p - buf + 2 <= len) {
272 debug(DBG_WARN, "buf2radmsg: invalid attribute length %d", l);
278 if (p - buf + l > len) {
279 debug(DBG_WARN, "buf2radmsg: attribute length %d exceeds packet length", l + 2);
287 if (t == RAD_Attr_Message_Authenticator && secret) {
289 memcpy(buf + 4, rqauth, 16);
290 if (l != 16 || !_checkmsgauth(buf, v, secret)) {
291 debug(DBG_WARN, "buf2radmsg: message authentication failed");
293 memcpy(buf + 4, msg->auth, 16);
298 memcpy(buf + 4, msg->auth, 16);
299 debug(DBG_DBG, "buf2radmsg: message auth ok");
302 attr = maketlv(t, l, v);
303 if (!attr || !radmsg_add(msg, attr)) {
312 /* Local Variables: */
313 /* c-file-style: "stroustrup" */