external/bsd/ntp/dist/libntp/a_md5encrypt.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  *      digest support for NTP, MD5 and with OpenSSL more
   5  */
   6 #ifdef HAVE_CONFIG_H
   7 #include <config.h>
   8 #endif
   9
  10 #include "ntp_fp.h"
  11 #include "ntp_string.h"
  12 #include "ntp_stdlib.h"
  13 #include "ntp.h"
  14 #ifdef OPENSSL
  15 #include "openssl/evp.h"
  16 #else
  17 #include "ntp_md5.h"
  18 #endif /* OPENSSSL */
  19
  20 /*
  21  * MD5authencrypt - generate message digest
  22  *
  23  * Returns length of MAC including key ID and digest.
  24  */
  25 int
  26 MD5authencrypt(
  27         int     type,           /* hash algorithm */
  28         u_char  *key,           /* key pointer */
  29         u_int32 *pkt,           /* packet pointer */
  30         int     length          /* packet length */
  31         )
  32 {
  33         u_char  digest[EVP_MAX_MD_SIZE];
  34         u_int   len;
  35 #ifdef OPENSSL
  36         EVP_MD_CTX ctx;
  37 #else
  38         MD5_CTX md5;
  39 #endif /* OPENSSL */
  40
  41         /*
  42          * Compute digest of key concatenated with packet. Note: the
  43          * key type and digest type have been verified when the key
  44          * was creaded.
  45          */
  46 #ifdef OPENSSL
  47         INIT_SSL();
  48         EVP_DigestInit(&ctx, EVP_get_digestbynid(type));
  49         EVP_DigestUpdate(&ctx, key, (u_int)cache_keylen);
  50         EVP_DigestUpdate(&ctx, (u_char *)pkt, (u_int)length);
  51         EVP_DigestFinal(&ctx, digest, &len);
  52 #else /* OPENSSL */
  53         MD5Init(&md5);
  54         MD5Update(&md5, key, (u_int)cache_keylen);
  55         MD5Update(&md5, (u_char *)pkt, (u_int)length);
  56         MD5Final(digest, &md5);
  57         len = 16;
  58 #endif /* OPENSSL */
  59         memmove((u_char *)pkt + length + 4, digest, len);
  60         return (len + 4);
  61 }
  62
  63
  64 /*
  65  * MD5authdecrypt - verify MD5 message authenticator
  66  *
  67  * Returns one if digest valid, zero if invalid.
  68  */
  69 int
  70 MD5authdecrypt(
  71         int     type,           /* hash algorithm */
  72         u_char  *key,           /* key pointer */
  73         u_int32 *pkt,           /* packet pointer */
  74         int     length,         /* packet length */
  75         int     size            /* MAC size */
  76         )
  77 {
  78         u_char  digest[EVP_MAX_MD_SIZE];
  79         u_int   len;
  80 #ifdef OPENSSL
  81         EVP_MD_CTX ctx;
  82 #else
  83         MD5_CTX md5;
  84 #endif /* OPENSSL */
  85
  86         /*
  87          * Compute digest of key concatenated with packet. Note: the
  88          * key type and digest type have been verified when the key
  89          * was created.
  90          */
  91 #ifdef OPENSSL
  92         INIT_SSL();
  93         EVP_DigestInit(&ctx, EVP_get_digestbynid(type));
  94         EVP_DigestUpdate(&ctx, key, (u_int)cache_keylen);
  95         EVP_DigestUpdate(&ctx, (u_char *)pkt, (u_int)length);
  96         EVP_DigestFinal(&ctx, digest, &len);
  97 #else /* OPENSSL */
  98         MD5Init(&md5);
  99         MD5Update(&md5, key, (u_int)cache_keylen);
 100         MD5Update(&md5, (u_char *)pkt, (u_int)length);
 101         MD5Final(digest, &md5);
 102         len = 16;
 103 #endif /* OPENSSL */
 104         if ((u_int)size != len + 4) {
 105                 msyslog(LOG_ERR,
 106                     "MAC decrypt: MAC length error");
 107                 return (0);
 108         }
 109         return (!memcmp(digest, (char *)pkt + length + 4, len));
 110 }
 111
 112 /*
 113  * Calculate the reference id from the address. If it is an IPv4
 114  * address, use it as is. If it is an IPv6 address, do a md5 on
 115  * it and use the bottom 4 bytes.
 116  */
 117 u_int32
 118 addr2refid(sockaddr_u *addr)
 119 {
 120         u_char          digest[20];
 121         u_int32         addr_refid;
 122 #ifdef OPENSSL
 123         EVP_MD_CTX      ctx;
 124         u_int           len;
 125 #else
 126         MD5_CTX md5;
 127 #endif /* OPENSSL */
 128
 129         if (IS_IPV4(addr))
 130                 return (NSRCADR(addr));
 131
 132 #ifdef OPENSSL
 133         INIT_SSL();
 134         EVP_DigestInit(&ctx, EVP_get_digestbynid(NID_md5));
 135         EVP_DigestUpdate(&ctx, (u_char *)PSOCK_ADDR6(addr),
 136             sizeof(struct in6_addr));
 137         EVP_DigestFinal(&ctx, digest, &len);
 138 #else
 139         MD5Init(&md5);
 140         MD5Update(&md5, (u_char *)PSOCK_ADDR6(addr),
 141             sizeof(struct in6_addr));
 142         MD5Final(digest, &md5);
 143 #endif /* OPENSSL */
 144         memcpy(&addr_refid, digest, 4);
 145         return (addr_refid);
 146 }