diff options
Diffstat (limited to 'lib/bind/nameser/ns_sign.c')
| -rw-r--r-- | lib/bind/nameser/ns_sign.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/lib/bind/nameser/ns_sign.c b/lib/bind/nameser/ns_sign.c new file mode 100644 index 0000000..ab4b0ef --- /dev/null +++ b/lib/bind/nameser/ns_sign.c @@ -0,0 +1,387 @@ +/* + * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") + * Copyright (c) 1999 by Internet Software Consortium, 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 ISC DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC 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 THIS SOFTWARE. + */ + +#ifndef lint +static const char rcsid[] = "$Id: ns_sign.c,v 1.4.18.2 2006/03/10 00:20:08 marka Exp $"; +#endif + +/* Import. */ + +#include "port_before.h" +#include "fd_setsize.h" + +#include <sys/types.h> +#include <sys/param.h> + +#include <netinet/in.h> +#include <arpa/nameser.h> +#include <arpa/inet.h> + +#include <errno.h> +#include <netdb.h> +#include <resolv.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <unistd.h> + +#include <isc/dst.h> +#include <isc/assertions.h> + +#include "port_after.h" + +#define BOUNDS_CHECK(ptr, count) \ + do { \ + if ((ptr) + (count) > eob) { \ + errno = EMSGSIZE; \ + return(NS_TSIG_ERROR_NO_SPACE); \ + } \ + } while (0) + +/*% + * ns_sign + * + * Parameters: + *\li msg message to be sent + *\li msglen input - length of message + * output - length of signed message + *\li msgsize length of buffer containing message + *\li error value to put in the error field + *\li key tsig key used for signing + *\li querysig (response), the signature in the query + *\li querysiglen (response), the length of the signature in the query + *\li sig a buffer to hold the generated signature + *\li siglen input - length of signature buffer + * output - length of signature + * + * Errors: + *\li - bad input data (-1) + *\li - bad key / sign failed (-BADKEY) + *\li - not enough space (NS_TSIG_ERROR_NO_SPACE) + */ +int +ns_sign(u_char *msg, int *msglen, int msgsize, int error, void *k, + const u_char *querysig, int querysiglen, u_char *sig, int *siglen, + time_t in_timesigned) +{ + return(ns_sign2(msg, msglen, msgsize, error, k, + querysig, querysiglen, sig, siglen, + in_timesigned, NULL, NULL)); +} + +int +ns_sign2(u_char *msg, int *msglen, int msgsize, int error, void *k, + const u_char *querysig, int querysiglen, u_char *sig, int *siglen, + time_t in_timesigned, u_char **dnptrs, u_char **lastdnptr) +{ + HEADER *hp = (HEADER *)msg; + DST_KEY *key = (DST_KEY *)k; + u_char *cp, *eob; + u_char *lenp; + u_char *alg; + int n; + time_t timesigned; + u_char name[NS_MAXCDNAME]; + + dst_init(); + if (msg == NULL || msglen == NULL || sig == NULL || siglen == NULL) + return (-1); + + cp = msg + *msglen; + eob = msg + msgsize; + + /* Name. */ + if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) { + n = ns_name_pton(key->dk_key_name, name, sizeof name); + if (n != -1) + n = ns_name_pack(name, cp, eob - cp, + (const u_char **)dnptrs, + (const u_char **)lastdnptr); + + } else { + n = ns_name_pton("", name, sizeof name); + if (n != -1) + n = ns_name_pack(name, cp, eob - cp, NULL, NULL); + } + if (n < 0) + return (NS_TSIG_ERROR_NO_SPACE); + cp += n; + + /* Type, class, ttl, length (not filled in yet). */ + BOUNDS_CHECK(cp, INT16SZ + INT16SZ + INT32SZ + INT16SZ); + PUTSHORT(ns_t_tsig, cp); + PUTSHORT(ns_c_any, cp); + PUTLONG(0, cp); /*%< TTL */ + lenp = cp; + cp += 2; + + /* Alg. */ + if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) { + if (key->dk_alg != KEY_HMAC_MD5) + return (-ns_r_badkey); + n = dn_comp(NS_TSIG_ALG_HMAC_MD5, cp, eob - cp, NULL, NULL); + } + else + n = dn_comp("", cp, eob - cp, NULL, NULL); + if (n < 0) + return (NS_TSIG_ERROR_NO_SPACE); + alg = cp; + cp += n; + + /* Time. */ + BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ); + PUTSHORT(0, cp); + timesigned = time(NULL); + if (error != ns_r_badtime) + PUTLONG(timesigned, cp); + else + PUTLONG(in_timesigned, cp); + PUTSHORT(NS_TSIG_FUDGE, cp); + + /* Compute the signature. */ + if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) { + void *ctx; + u_char buf[NS_MAXCDNAME], *cp2; + int n; + + dst_sign_data(SIG_MODE_INIT, key, &ctx, NULL, 0, NULL, 0); + + /* Digest the query signature, if this is a response. */ + if (querysiglen > 0 && querysig != NULL) { + u_int16_t len_n = htons(querysiglen); + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, + (u_char *)&len_n, INT16SZ, NULL, 0); + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, + querysig, querysiglen, NULL, 0); + } + + /* Digest the message. */ + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, msg, *msglen, + NULL, 0); + + /* Digest the key name. */ + n = ns_name_ntol(name, buf, sizeof(buf)); + INSIST(n > 0); + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0); + + /* Digest the class and TTL. */ + cp2 = buf; + PUTSHORT(ns_c_any, cp2); + PUTLONG(0, cp2); + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, cp2-buf, + NULL, 0); + + /* Digest the algorithm. */ + n = ns_name_ntol(alg, buf, sizeof(buf)); + INSIST(n > 0); + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, n, NULL, 0); + + /* Digest the time signed, fudge, error, and other data */ + cp2 = buf; + PUTSHORT(0, cp2); /*%< Top 16 bits of time */ + if (error != ns_r_badtime) + PUTLONG(timesigned, cp2); + else + PUTLONG(in_timesigned, cp2); + PUTSHORT(NS_TSIG_FUDGE, cp2); + PUTSHORT(error, cp2); /*%< Error */ + if (error != ns_r_badtime) + PUTSHORT(0, cp2); /*%< Other data length */ + else { + PUTSHORT(INT16SZ+INT32SZ, cp2); /*%< Other data length */ + PUTSHORT(0, cp2); /*%< Top 16 bits of time */ + PUTLONG(timesigned, cp2); + } + dst_sign_data(SIG_MODE_UPDATE, key, &ctx, buf, cp2-buf, + NULL, 0); + + n = dst_sign_data(SIG_MODE_FINAL, key, &ctx, NULL, 0, + sig, *siglen); + if (n < 0) + return (-ns_r_badkey); + *siglen = n; + } else + *siglen = 0; + + /* Add the signature. */ + BOUNDS_CHECK(cp, INT16SZ + (*siglen)); + PUTSHORT(*siglen, cp); + memcpy(cp, sig, *siglen); + cp += (*siglen); + + /* The original message ID & error. */ + BOUNDS_CHECK(cp, INT16SZ + INT16SZ); + PUTSHORT(ntohs(hp->id), cp); /*%< already in network order */ + PUTSHORT(error, cp); + + /* Other data. */ + BOUNDS_CHECK(cp, INT16SZ); + if (error != ns_r_badtime) + PUTSHORT(0, cp); /*%< Other data length */ + else { + PUTSHORT(INT16SZ+INT32SZ, cp); /*%< Other data length */ + BOUNDS_CHECK(cp, INT32SZ+INT16SZ); + PUTSHORT(0, cp); /*%< Top 16 bits of time */ + PUTLONG(timesigned, cp); + } + + /* Go back and fill in the length. */ + PUTSHORT(cp - lenp - INT16SZ, lenp); + + hp->arcount = htons(ntohs(hp->arcount) + 1); + *msglen = (cp - msg); + return (0); +} + +int +ns_sign_tcp_init(void *k, const u_char *querysig, int querysiglen, + ns_tcp_tsig_state *state) +{ + dst_init(); + if (state == NULL || k == NULL || querysig == NULL || querysiglen < 0) + return (-1); + state->counter = -1; + state->key = k; + if (state->key->dk_alg != KEY_HMAC_MD5) + return (-ns_r_badkey); + if (querysiglen > (int)sizeof(state->sig)) + return (-1); + memcpy(state->sig, querysig, querysiglen); + state->siglen = querysiglen; + return (0); +} + +int +ns_sign_tcp(u_char *msg, int *msglen, int msgsize, int error, + ns_tcp_tsig_state *state, int done) +{ + return (ns_sign_tcp2(msg, msglen, msgsize, error, state, + done, NULL, NULL)); +} + +int +ns_sign_tcp2(u_char *msg, int *msglen, int msgsize, int error, + ns_tcp_tsig_state *state, int done, + u_char **dnptrs, u_char **lastdnptr) +{ + u_char *cp, *eob, *lenp; + u_char buf[MAXDNAME], *cp2; + HEADER *hp = (HEADER *)msg; + time_t timesigned; + int n; + + if (msg == NULL || msglen == NULL || state == NULL) + return (-1); + + state->counter++; + if (state->counter == 0) + return (ns_sign2(msg, msglen, msgsize, error, state->key, + state->sig, state->siglen, + state->sig, &state->siglen, 0, + dnptrs, lastdnptr)); + + if (state->siglen > 0) { + u_int16_t siglen_n = htons(state->siglen); + dst_sign_data(SIG_MODE_INIT, state->key, &state->ctx, + NULL, 0, NULL, 0); + dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx, + (u_char *)&siglen_n, INT16SZ, NULL, 0); + dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx, + state->sig, state->siglen, NULL, 0); + state->siglen = 0; + } + + dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx, msg, *msglen, + NULL, 0); + + if (done == 0 && (state->counter % 100 != 0)) + return (0); + + cp = msg + *msglen; + eob = msg + msgsize; + + /* Name. */ + n = dn_comp(state->key->dk_key_name, cp, eob - cp, dnptrs, lastdnptr); + if (n < 0) + return (NS_TSIG_ERROR_NO_SPACE); + cp += n; + + /* Type, class, ttl, length (not filled in yet). */ + BOUNDS_CHECK(cp, INT16SZ + INT16SZ + INT32SZ + INT16SZ); + PUTSHORT(ns_t_tsig, cp); + PUTSHORT(ns_c_any, cp); + PUTLONG(0, cp); /*%< TTL */ + lenp = cp; + cp += 2; + + /* Alg. */ + n = dn_comp(NS_TSIG_ALG_HMAC_MD5, cp, eob - cp, NULL, NULL); + if (n < 0) + return (NS_TSIG_ERROR_NO_SPACE); + cp += n; + + /* Time. */ + BOUNDS_CHECK(cp, INT16SZ + INT32SZ + INT16SZ); + PUTSHORT(0, cp); + timesigned = time(NULL); + PUTLONG(timesigned, cp); + PUTSHORT(NS_TSIG_FUDGE, cp); + + /* + * Compute the signature. + */ + + /* Digest the time signed and fudge. */ + cp2 = buf; + PUTSHORT(0, cp2); /*%< Top 16 bits of time */ + PUTLONG(timesigned, cp2); + PUTSHORT(NS_TSIG_FUDGE, cp2); + + dst_sign_data(SIG_MODE_UPDATE, state->key, &state->ctx, + buf, cp2 - buf, NULL, 0); + + n = dst_sign_data(SIG_MODE_FINAL, state->key, &state->ctx, NULL, 0, + state->sig, sizeof(state->sig)); + if (n < 0) + return (-ns_r_badkey); + state->siglen = n; + + /* Add the signature. */ + BOUNDS_CHECK(cp, INT16SZ + state->siglen); + PUTSHORT(state->siglen, cp); + memcpy(cp, state->sig, state->siglen); + cp += state->siglen; + + /* The original message ID & error. */ + BOUNDS_CHECK(cp, INT16SZ + INT16SZ); + PUTSHORT(ntohs(hp->id), cp); /*%< already in network order */ + PUTSHORT(error, cp); + + /* Other data. */ + BOUNDS_CHECK(cp, INT16SZ); + PUTSHORT(0, cp); + + /* Go back and fill in the length. */ + PUTSHORT(cp - lenp - INT16SZ, lenp); + + hp->arcount = htons(ntohs(hp->arcount) + 1); + *msglen = (cp - msg); + return (0); +} + +/*! \file */ |
