diff options
Diffstat (limited to 'contrib/bind/lib/nameser/ns_sign.c')
-rw-r--r-- | contrib/bind/lib/nameser/ns_sign.c | 348 |
1 files changed, 348 insertions, 0 deletions
diff --git a/contrib/bind/lib/nameser/ns_sign.c b/contrib/bind/lib/nameser/ns_sign.c new file mode 100644 index 0000000000000..75af894695282 --- /dev/null +++ b/contrib/bind/lib/nameser/ns_sign.c @@ -0,0 +1,348 @@ +/* + * 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS + * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE + * CONSORTIUM 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 8.8 1999/10/13 16:39:36 vixie 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 <unistd.h> + +#include <isc/dst.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: + * msg message to be sent + * msglen input - length of message + * output - length of signed message + * msgsize length of buffer containing message + * error value to put in the error field + * key tsig key used for signing + * querysig (response), the signature in the query + * querysiglen (response), the length of the signature in the query + * sig a buffer to hold the generated signature + * siglen input - length of signature buffer + * output - length of signature + * + * Errors: + * - bad input data (-1) + * - bad key / sign failed (-BADKEY) + * - 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) +{ + HEADER *hp = (HEADER *)msg; + DST_KEY *key = (DST_KEY *)k; + u_char *cp = msg + *msglen, *eob = msg + msgsize; + u_char *lenp; + u_char *name, *alg; + int n; + time_t timesigned; + + dst_init(); + if (msg == NULL || msglen == NULL || sig == NULL || siglen == NULL) + return (-1); + + /* Name. */ + if (key != NULL && error != ns_r_badsig && error != ns_r_badkey) + n = dn_comp(key->dk_key_name, cp, eob - cp, NULL, NULL); + else + n = dn_comp("", cp, eob - cp, NULL, NULL); + if (n < 0) + return (NS_TSIG_ERROR_NO_SPACE); + name = cp; + 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[MAXDNAME], *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)); + 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)); + 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 > 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) +{ + 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_sign(msg, msglen, msgsize, error, state->key, + state->sig, state->siglen, + state->sig, &state->siglen, 0)); + + 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, 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. */ + 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); +} |