diff options
Diffstat (limited to 'contrib/bind/lib/dst/cylink_link.c')
| -rw-r--r-- | contrib/bind/lib/dst/cylink_link.c | 676 |
1 files changed, 676 insertions, 0 deletions
diff --git a/contrib/bind/lib/dst/cylink_link.c b/contrib/bind/lib/dst/cylink_link.c new file mode 100644 index 000000000000..c7cb2767410b --- /dev/null +++ b/contrib/bind/lib/dst/cylink_link.c @@ -0,0 +1,676 @@ +#ifdef CYLINK_DSS +static const char rcsid[] = "$Header: /proj/cvs/isc/bind/src/lib/dst/cylink_link.c,v 1.7 1999/10/13 16:39:22 vixie Exp $"; + +/* + * Portions Copyright (c) 1995-1998 by Trusted Information Systems, Inc. + * + * Permission to use, copy modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND TRUSTED INFORMATION SYSTEMS + * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * TRUSTED INFORMATION SYSTEMS BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING + * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, + * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION + * WITH THE USE OR PERFORMANCE OF THE SOFTWARE. + */ +/* + * This file contains two components + * 1. Interface to the CYLINK library to allow compilation of Bind + * with TIS/DNSSEC when CYLINK is not available + * all calls to CYLINK are contained inside this file. + * 2. The glue to connvert DSA KEYS to and from external formats + */ +#include "port_before.h" + +#include <stdio.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <memory.h> +#include <sys/param.h> +#include <sys/time.h> +#include <netinet/in.h> + +#include "dst_internal.h" +#include <toolkit.h> + +#include "port_after.h" + +typedef struct cylinkkey { + char *dk_signer; + uchar *dk_p; + uchar *dk_q; + uchar *dk_g; + uchar *dk_x; + uchar *dk_y; + ushort dk_p_bytes; +} DSA_Key; + +#define NULL_PRIV_KEY(k)(k == NULL || k->dk_p == NULL || k->dk_q == NULL || \ + k->dk_g == NULL || k->dk_x == NULL) +#define NULL_PUB_KEY(k)(k == NULL || k->dk_p == NULL || k->dk_q == NULL || \ + k->dk_g == NULL || k->dk_y == NULL) + +static int dst_cylink_sign(const int mode, DST_KEY *dkey, void **context, + const u_char *data, const int len, + u_char *signature, const int sig_len); + +static int dst_cylink_verify(const int mode, DST_KEY *dkey, void **context, + const u_char *data, const int len, + const u_char *signature, const int sig_len); + +static int dst_cylink_to_dns_key(const DST_KEY *in_key, u_char *out_str, + const int out_len); +static int dst_cylink_from_dns_key(DST_KEY *s_key, const u_char *key, + const int len); +static int dst_cylink_key_to_file_format(const DST_KEY *key, char *buff, + const int buff_len); +static int dst_cylink_key_from_file_format(DST_KEY *d_key, + const char *buff, + const int buff_len); +static void *dst_cylink_free_key_structure(void *key); + +static int dst_cylink_generate_keypair(DST_KEY *key, int exp); +static int dst_cylink_compare_keys(const DST_KEY *key1, const DST_KEY *key2); + +static void *memcpyend(void *dest, const void *src, size_t n, size_t size); + +/* + * dst_cylink_init() Function to answer set up function pointers for + * CYLINK related functions + */ +int +dst_cylink_init() +{ + if (dst_t_func[KEY_DSA] != NULL) + return (1); + dst_t_func[KEY_DSA] = malloc(sizeof(struct dst_func)); + if (dst_t_func[KEY_DSA] == NULL) + return (0); + memset(dst_t_func[KEY_DSA], 0, sizeof(struct dst_func)); + dst_t_func[KEY_DSA]->sign = dst_cylink_sign; + dst_t_func[KEY_DSA]->verify = dst_cylink_verify; + dst_t_func[KEY_DSA]->compare = dst_cylink_compare_keys; + dst_t_func[KEY_DSA]->generate = dst_cylink_generate_keypair; + dst_t_func[KEY_DSA]->destroy = dst_cylink_free_key_structure; + dst_t_func[KEY_DSA]->from_dns_key = dst_cylink_from_dns_key; + dst_t_func[KEY_DSA]->to_dns_key = dst_cylink_to_dns_key; + dst_t_func[KEY_DSA]->from_file_fmt = dst_cylink_key_from_file_format; + dst_t_func[KEY_DSA]->to_file_fmt = dst_cylink_key_to_file_format; + SetDataOrder(1); + return (1); +} + +/* + * dst_cylink_sign + * Call CYLINK signing functions to sign a block of data. + * There are three steps to signing, INIT (initialize structures), + * UPDATE (hash (more) data), FINAL (generate a signature). This + * routine performs one or more of these steps. + * Parameters + * mode SIG_MODE_INIT, SIG_MODE_UPDATE and/or SIG_MODE_FINAL. + * algobj structure holds context for a sign done in multiple calls. + * context the context to use for this computation + * data data to be signed. + * len length in bytes of data. + * priv_key key to use for signing. + * signature location to store signature. + * sig_len size in bytes of signature field. + * returns + * N Success on SIG_MODE_FINAL = returns signature length in bytes + * N is 41 for DNS + * 0 Success on SIG_MODE_INIT and UPDATE + * <0 Failure + */ + +static int +dst_cylink_sign(const int mode, DST_KEY *dkey, void **context, + const u_char *data, const int len, + u_char *signature, const int sig_len) +{ + int sign_len = 0; + int status; + SHA_context *ctx = NULL; + + if (mode & SIG_MODE_INIT) + ctx = (SHA_context *) malloc(sizeof(SHA_context)); + else if (context) + ctx = (SHA_context *) *context; + if (ctx == NULL) + return (-1); + + if (mode & SIG_MODE_INIT) + SHAInit(ctx); + + if ((mode & SIG_MODE_UPDATE) && (data && len > 0)) { + status = SHAUpdate(ctx, (u_char *) data, len); + if (status != SUCCESS) + return (SIGN_UPDATE_FAILURE); + } + if (mode & SIG_MODE_FINAL) { + DSA_Key *key; + uchar digest[SHA_LENGTH]; + uchar rand[SHA_LENGTH]; + uchar r[SHA_LENGTH], s[SHA_LENGTH]; + + if (signature == NULL || sig_len < 2 * SHA_LENGTH) + return (SIGN_FINAL_FAILURE); + if ((status = SHAFinal(ctx, digest)) != SUCCESS) + return (SIGN_FINAL_FAILURE); + SAFE_FREE(ctx); + if (dkey == NULL || dkey->dk_KEY_struct == NULL) + return (-1); + key = (DSA_Key *) dkey->dk_KEY_struct; + if (NULL_PRIV_KEY(key)) + return (-2); + dst_random(DST_RAND_STD, sizeof(rand), rand); + status = GenDSSSignature(key->dk_p_bytes, key->dk_p, + key->dk_q, key->dk_g, key->dk_x, + rand, r, s, digest); + if (status != SUCCESS) + return (SIGN_FINAL_FAILURE); + *signature = (dkey->dk_key_size - 512)/64; + sign_len = 1; + memcpy(signature + sign_len, r, SHA_LENGTH); + sign_len += SHA_LENGTH; + memcpy(signature + sign_len, s, SHA_LENGTH); + sign_len += SHA_LENGTH; + } + else { + if (context == NULL) + return (-1); + *context = (void *) ctx; + } + return (sign_len); +} + + +/* + * Dst_cylink_verify + * Calls CYLINK verification routines. There are three steps to + * verification, INIT (initialize structures), UPDATE (hash (more) data), + * FINAL (generate a signature). This routine performs one or more of + * these steps. + * Parameters + * mode SIG_MODE_INIT, SIG_MODE_UPDATE and/or SIG_MODE_FINAL. + * dkey structure holds context for a verify done in multiple calls. + * context algorithm specific context for the current context processing + * data data signed. + * len length in bytes of data. + * pub_key key to use for verify. + * signature signature. + * sig_len length in bytes of signature. + * returns + * 0 Success + * <0 Failure + */ + +static int +dst_cylink_verify(const int mode, DST_KEY *dkey, void **context, + const u_char *data, const int len, + const u_char *signature, const int sig_len) +{ + int status; + SHA_context *ctx = NULL; + + if (mode & SIG_MODE_INIT) + ctx = (SHA_context *) malloc(sizeof(SHA_context)); + else if (context) + ctx = (SHA_context *) *context; + if (ctx == NULL) + return (-1); + + if (mode & SIG_MODE_INIT) + SHAInit(ctx); + + if ((mode & SIG_MODE_UPDATE) && (data && len > 0)) { + status = SHAUpdate(ctx, (u_char *) data, len); + if (status != SUCCESS) + return (VERIFY_UPDATE_FAILURE); + } + if (mode & SIG_MODE_FINAL) { + DSA_Key *key; + uchar digest[SHA_LENGTH]; + uchar r[SHA_LENGTH], s[SHA_LENGTH]; + + if (dkey == NULL || dkey->dk_KEY_struct == NULL) + return (-1); + key = (DSA_Key *) dkey->dk_KEY_struct; + if (NULL_PUB_KEY(key)) + return (-2); + if (signature == NULL || sig_len != (2 * SHA_LENGTH +1)) + return (SIGN_FINAL_FAILURE); + status = SHAFinal(ctx, digest); + SAFE_FREE(ctx); + if (status != SUCCESS) + return (SIGN_FINAL_FAILURE); + if (((int)*signature) != ((key->dk_p_bytes -64)/8)) + return(VERIFY_FINAL_FAILURE); + + memcpy(r, signature +1, SHA_LENGTH); + memcpy(s, signature + SHA_LENGTH +1, SHA_LENGTH); + status = VerDSSSignature(key->dk_p_bytes, key->dk_p, + key->dk_q, key->dk_g, key->dk_y, + r, s, digest); + if (status != SUCCESS) + return (VERIFY_FINAL_FAILURE); + } + else { + if (context == NULL) + return (-1); + *context = (void *) ctx; + } + return (0); +} + + +/* + * dst_cylink_to_dns_key + * Converts key from DSA to DNS distribution format + * This function gets in a pointer to the public key and a work area + * to write the key into. + * Parameters + * public KEY structure + * out_str buffer to write encoded key into + * out_len size of out_str + * Return + * N >= 0 length of encoded key + * n < 0 error + */ + +static int +dst_cylink_to_dns_key(const DST_KEY *in_key, u_char *out_str, + const int out_len) +{ + u_char *op = out_str; + int t; + DSA_Key *key; + + if (in_key == NULL || in_key->dk_KEY_struct == NULL || + out_len <= 0 || out_str == NULL) + return (-1); + key = (DSA_Key *) in_key->dk_KEY_struct; + + t = (key->dk_p_bytes - 64) / 8; + + *op++ = t; + memcpy(op, key->dk_q, SHA_LENGTH); + op += SHA_LENGTH; + memcpy(op, key->dk_p, key->dk_p_bytes); + op += key->dk_p_bytes; + memcpy(op, key->dk_g, key->dk_p_bytes); + op += key->dk_p_bytes; + memcpy(op, key->dk_y, key->dk_p_bytes); + op += key->dk_p_bytes; + + return (op - out_str); +} + + +/* + * dst_cylink_from_dns_key + * Converts from a DNS KEY RR format to an RSA KEY. + * Parameters + * len Length in bytes of DNS key + * key DNS key + * name Key name + * s_key DST structure that will point to the RSA key this routine + * will build. + * Return + * 0 The input key, s_key or name was null. + * 1 Success + */ +static int +dst_cylink_from_dns_key(DST_KEY *s_key, const u_char *key, const int len) +{ + int t; + const u_char *key_ptr = key; + DSA_Key *d_key; + + if (s_key == NULL || len < 0 || key == NULL) + return (0); + + if (len == 0) /* process null key */ + return (1); + + if (key_ptr == NULL) + return (0); + t = (int) *key_ptr++; /* length of exponent in bytes */ + + if ((3 * (t * 8 + 64) + SHA_LENGTH + 1) != len) + return (0); + + if ((d_key = (DSA_Key *) malloc(sizeof(DSA_Key))) == NULL) { + EREPORT(("dst_cylink_from_dns_key(): Memory allocation error 1")); + return (0); + } + memset(d_key, 0, sizeof(DSA_Key)); + s_key->dk_KEY_struct = (void *) d_key; + d_key->dk_signer = strdup(s_key->dk_key_name); + d_key->dk_p_bytes = 64 + 8 * t; + + if ((d_key->dk_q = (uchar *) malloc(SHA_LENGTH)) == NULL) + return (0); + memcpy(d_key->dk_q, key_ptr, SHA_LENGTH); + key_ptr += SHA_LENGTH; + + if ((d_key->dk_p = (uchar *) malloc(d_key->dk_p_bytes)) == NULL) + return (0); + memcpy(d_key->dk_p, key_ptr, d_key->dk_p_bytes); + key_ptr += d_key->dk_p_bytes; + + if ((d_key->dk_g = (uchar *) malloc(d_key->dk_p_bytes)) == NULL) + return (0); + memcpy(d_key->dk_g, key_ptr, d_key->dk_p_bytes); + key_ptr += d_key->dk_p_bytes; + + if ((d_key->dk_y = (uchar *) malloc(d_key->dk_p_bytes)) == NULL) + return (0); + memcpy(d_key->dk_y, key_ptr, d_key->dk_p_bytes); + key_ptr += d_key->dk_p_bytes; + + s_key->dk_id = dst_s_id_calc(key, len); + s_key->dk_key_size = d_key->dk_p_bytes * 8; + return (1); +} + + +/************************************************************************** + * dst_cylink_key_to_file_format + * Encodes an DSA Key into the portable file format. + * Parameters + * key DSA KEY structure + * buff output buffer + * buff_len size of output buffer + * Return + * 0 Failure - null input rkey + * -1 Failure - not enough space in output area + * N Success - Length of data returned in buff + */ + +static int +dst_cylink_key_to_file_format(const DST_KEY *key, char *buff, + const int buff_len) +{ + char *bp; + int len, b_len; + DSA_Key *dkey; + u_char num[256]; /* More than long enough for DSA keys */ + + if (key == NULL || key->dk_KEY_struct == NULL) /* no output */ + return (0); + if (buff == NULL || buff_len <= (int) strlen(key_file_fmt_str)) + return (-1); /* no OR not enough space in output area */ + + dkey = (DSA_Key *) key->dk_KEY_struct; + + memset(buff, 0, buff_len); /* just in case */ + /* write file header */ + sprintf(buff, key_file_fmt_str, KEY_FILE_FORMAT, KEY_DSA, "DSA"); + + bp = (char *) strchr(buff, '\0'); + b_len = buff_len - (bp - buff); + memcpy(num, dkey->dk_p, dkey->dk_p_bytes); + if ((len = dst_s_conv_bignum_u8_to_b64(bp, b_len, "Prime(p): ", + num, dkey->dk_p_bytes)) <= 0) + return (-1); + + bp = (char *) strchr(buff, '\0'); + b_len = buff_len - (bp - buff); + memcpy(num, dkey->dk_q, dkey->dk_p_bytes); + if ((len = dst_s_conv_bignum_u8_to_b64(bp, b_len, "Subprime(q): ", + num, SHA_LENGTH)) <= 0) + return (-2); + + bp = (char *) strchr(buff, '\0'); + b_len = buff_len - (bp - buff); + memcpy(num, dkey->dk_g, dkey->dk_p_bytes); + if ((len = dst_s_conv_bignum_u8_to_b64(bp, b_len, "Base(g): ", + num, dkey->dk_p_bytes)) <= 0) + return (-3); + + bp = (char *) strchr(buff, '\0'); + b_len = buff_len - (bp - buff); + memcpy(num, dkey->dk_x, dkey->dk_p_bytes); + if ((len = dst_s_conv_bignum_u8_to_b64(bp, b_len, "Private_value(x): ", + num, SHA_LENGTH)) <= 0) + return (-4); + + bp = (char *) strchr(buff, '\0'); + b_len = buff_len - (bp - buff); + memcpy(num, dkey->dk_y, dkey->dk_p_bytes); + if ((len = dst_s_conv_bignum_u8_to_b64(bp, b_len, "Public_value(y): ", + num, dkey->dk_p_bytes)) <= 0) + return (-4); + + bp += len; + b_len -= len; + return (buff_len - b_len); +} + + +/************************************************************************** + * dst_cylink_key_from_file_format + * Converts contents of a private key file into a private DSA key. + * Parameters + * DSA_Key structure to put key into + * buff buffer containing the encoded key + * buff_len the length of the buffer + * Return + * n >= 0 Foot print of the key converted + * n < 0 Error in conversion + */ + +static int +dst_cylink_key_from_file_format(DST_KEY *d_key, const char *buff, + const int buff_len) +{ + u_char s[DSS_LENGTH_MAX]; + u_char dns[1024]; + int len, s_len = sizeof(s); + int foot = -1, dnslen; + const char *p = buff; + DSA_Key *dsa_key; + + if (d_key == NULL || buff == NULL || buff_len <= 0) + return (-1); + + dsa_key = (DSA_Key *) malloc(sizeof(DSA_Key)); + if (dsa_key == NULL) { + return (-2); + } + memset(dsa_key, 0, sizeof(*dsa_key)); + d_key->dk_KEY_struct = (void *) dsa_key; + + if (!dst_s_verify_str(&p, "Prime(p): ")) + return (-3); + memset(s, 0, s_len); + if ((len = dst_s_conv_bignum_b64_to_u8(&p, s, s_len)) == 0) + return (-4); + dsa_key->dk_p_bytes = len; + if ((dsa_key->dk_p = malloc(len)) == NULL) + return (-5); + memcpy(dsa_key->dk_p, s + s_len - len, len); + + while (*++p && p < (const char *) &buff[buff_len]) { + if (dst_s_verify_str(&p, "Subprime(q): ")) { + if (!(len = dst_s_conv_bignum_b64_to_u8(&p, s, s_len))) + return (-6); + if ((dsa_key->dk_q = malloc(SHA_LENGTH)) == NULL) + return (-7); + memcpyend(dsa_key->dk_q, s + s_len - len, len, + SHA_LENGTH); + } else if (dst_s_verify_str(&p, "Base(g): ")) { + if (!(len = dst_s_conv_bignum_b64_to_u8(&p, s, s_len))) + return (-8); + if ((dsa_key->dk_g = malloc(dsa_key->dk_p_bytes)) + == NULL) + return (-9); + memcpyend(dsa_key->dk_g, s + s_len - len, len, + dsa_key->dk_p_bytes); + } else if (dst_s_verify_str(&p, "Private_value(x): ")) { + if (!(len = dst_s_conv_bignum_b64_to_u8(&p, s, s_len))) + return (-10); + if ((dsa_key->dk_x = malloc(SHA_LENGTH)) == NULL) + return (-11); + memcpyend(dsa_key->dk_x, s + s_len - len, len, + SHA_LENGTH); + } else if (dst_s_verify_str(&p, "Public_value(y): ")) { + if (!(len = dst_s_conv_bignum_b64_to_u8(&p, s, s_len))) + return (-10); + if ((dsa_key->dk_y = malloc(dsa_key->dk_p_bytes)) + == NULL) + return (-11); + memcpyend(dsa_key->dk_y, s + s_len - len, len, + dsa_key->dk_p_bytes); + } else { + EREPORT(("Decode_DSAKey(): Bad keyword %s\n", p)); + return (-12); + } + } /* while p */ + + d_key->dk_key_size = dsa_key->dk_p_bytes * 8; + dnslen = d_key->dk_func->to_dns_key(d_key, dns, sizeof(dns)); + foot = dst_s_id_calc(dns, dnslen); + + return (foot); +} + + +/************************************************************************** + * dst_cylink_free_key_structure + * Frees all dynamicly allocated structures in DSA_Key. + */ + +static void * +dst_cylink_free_key_structure(void *key) +{ + DSA_Key *d_key = (DSA_Key *) key; + if (d_key != NULL) { + SAFE_FREE(d_key->dk_signer); + SAFE_FREE(d_key->dk_p); + SAFE_FREE(d_key->dk_q); + SAFE_FREE(d_key->dk_g); + SAFE_FREE(d_key->dk_x); + SAFE_FREE(d_key->dk_y); + SAFE_FREE(d_key); + } + return (NULL); +} + + +/************************************************************************** + * dst_cylink_generate_keypair + * Generates unique keys that are hard to predict. + * Parameters + * key generic Key structure + * exp the public exponent + * Return + * 0 Failure + * 1 Success + */ + +static int +dst_cylink_generate_keypair(DST_KEY *key, int nothing) +{ + int status, dnslen, n; + DSA_Key *dsa; + u_char rand[SHA_LENGTH]; + u_char dns[1024]; + + if (key == NULL || key->dk_alg != KEY_DSA) + return (0); + + if ((dsa = (DSA_Key *) malloc(sizeof(DSA_Key))) == NULL) { + EREPORT(("dst_cylink_generate_keypair: Memory allocation error 3")); + return (0); + } + memset(dsa, 0, sizeof(*dsa)); + + dsa->dk_p_bytes = key->dk_key_size / 8; + dsa->dk_p = (uchar *) malloc(dsa->dk_p_bytes); + dsa->dk_q = (uchar *) malloc(SHA_LENGTH); + dsa->dk_g = (uchar *) malloc(dsa->dk_p_bytes); + dsa->dk_x = (uchar *) malloc(SHA_LENGTH); + dsa->dk_y = (uchar *) malloc(dsa->dk_p_bytes); + if (!dsa->dk_p || !dsa->dk_q || !dsa->dk_g || !dsa->dk_x || !dsa->dk_y) { + EREPORT(("dst_cylink_generate_keypair: Memory allocation error 4")); + return (0); + } + n = dst_random(DST_RAND_KEY, sizeof(rand), rand); + if (n != sizeof(rand)) + return (0); + status = GenDSSParameters(dsa->dk_p_bytes, dsa->dk_p, dsa->dk_q, + dsa->dk_g, rand, NULL); + if (status != SUCCESS) + return (0); + + status = GenDSSKey(dsa->dk_p_bytes, dsa->dk_p, dsa->dk_q, dsa->dk_g, + dsa->dk_x, dsa->dk_y, rand); + if (status != SUCCESS) + return (0); + memset(rand, 0, sizeof(rand)); + key->dk_KEY_struct = (void *) dsa; + dnslen = key->dk_func->to_dns_key(key, dns, sizeof(dns)); + key->dk_id = dst_s_id_calc(dns, dnslen); + return (1); +} + + +/* + * dst_cylink_compare_keys + * Compare two keys for equality. + * Return + * 0 The keys are equal + * NON-ZERO The keys are not equal + */ + +static int +dst_cylink_compare_keys(const DST_KEY *key1, const DST_KEY *key2) +{ + int status; + DSA_Key *dkey1 = (DSA_Key *) key1->dk_KEY_struct; + DSA_Key *dkey2 = (DSA_Key *) key2->dk_KEY_struct; + + if (dkey1 == NULL && dkey2 == NULL) + return (0); + else if (dkey1 == NULL) + return (2); + else if (dkey2 == NULL) + return(1); + + if (dkey1->dk_p_bytes != dkey2->dk_p_bytes) + return (201); + status = memcmp(dkey1->dk_p, dkey2->dk_p, dkey1->dk_p_bytes) || + memcmp(dkey1->dk_q, dkey2->dk_q, SHA_LENGTH) || + memcmp(dkey1->dk_g, dkey2->dk_g, dkey1->dk_p_bytes) || + memcmp(dkey1->dk_y, dkey2->dk_y, dkey1->dk_p_bytes); + if (status) + return (status); + if (dkey1->dk_x || dkey2->dk_x) { + if (dkey1->dk_x == NULL || dkey2->dk_x == NULL) + return (202); + return (memcmp(dkey1->dk_x, dkey2->dk_x, dkey1->dk_p_bytes)); + } else + return (0); +} + +static void * +memcpyend(void *dest, const void *src, size_t n, size_t size) { + if (n < size) + memset(dest, 0, size - n); + memcpy((char *)dest + size - n, src, n); + return dest; +} + +#else +int +dst_cylink_init() +{ + return (0); +} +#endif /* CYLINK */ |