version 1.53, 2003/04/08 20:21:29 |
version 1.54, 2003/07/22 13:35:22 |
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#include <openssl/bn.h> |
#include <openssl/bn.h> |
#include <openssl/md5.h> |
#include <openssl/md5.h> |
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#ifdef KRB4 |
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#include <krb.h> |
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#endif |
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#ifdef KRB5 |
#ifdef KRB5 |
#include <krb5.h> |
#include <krb5.h> |
#endif |
#endif |
#ifdef AFS |
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#include <kafs.h> |
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#include "radix.h" |
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#endif |
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#include "ssh.h" |
#include "ssh.h" |
#include "ssh1.h" |
#include "ssh1.h" |
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return 0; |
return 0; |
} |
} |
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#ifdef KRB4 |
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static int |
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try_krb4_authentication(void) |
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{ |
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KTEXT_ST auth; /* Kerberos data */ |
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char *reply; |
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char inst[INST_SZ]; |
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char *realm; |
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CREDENTIALS cred; |
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int r, type; |
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socklen_t slen; |
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Key_schedule schedule; |
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u_long checksum, cksum; |
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MSG_DAT msg_data; |
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struct sockaddr_in local, foreign; |
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struct stat st; |
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/* Don't do anything if we don't have any tickets. */ |
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if (stat(tkt_string(), &st) < 0) |
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return 0; |
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strlcpy(inst, (char *)krb_get_phost(get_canonical_hostname(1)), |
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INST_SZ); |
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realm = (char *)krb_realmofhost(get_canonical_hostname(1)); |
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if (!realm) { |
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debug("Kerberos v4: no realm for %s", get_canonical_hostname(1)); |
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return 0; |
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} |
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/* This can really be anything. */ |
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checksum = (u_long)getpid(); |
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r = krb_mk_req(&auth, KRB4_SERVICE_NAME, inst, realm, checksum); |
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if (r != KSUCCESS) { |
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debug("Kerberos v4 krb_mk_req failed: %s", krb_err_txt[r]); |
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return 0; |
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} |
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/* Get session key to decrypt the server's reply with. */ |
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r = krb_get_cred(KRB4_SERVICE_NAME, inst, realm, &cred); |
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if (r != KSUCCESS) { |
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debug("get_cred failed: %s", krb_err_txt[r]); |
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return 0; |
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} |
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des_key_sched((des_cblock *) cred.session, schedule); |
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/* Send authentication info to server. */ |
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packet_start(SSH_CMSG_AUTH_KERBEROS); |
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packet_put_string((char *) auth.dat, auth.length); |
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packet_send(); |
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packet_write_wait(); |
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/* Zero the buffer. */ |
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(void) memset(auth.dat, 0, MAX_KTXT_LEN); |
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slen = sizeof(local); |
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memset(&local, 0, sizeof(local)); |
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if (getsockname(packet_get_connection_in(), |
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(struct sockaddr *)&local, &slen) < 0) |
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debug("getsockname failed: %s", strerror(errno)); |
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slen = sizeof(foreign); |
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memset(&foreign, 0, sizeof(foreign)); |
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if (getpeername(packet_get_connection_in(), |
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(struct sockaddr *)&foreign, &slen) < 0) { |
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debug("getpeername failed: %s", strerror(errno)); |
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fatal_cleanup(); |
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} |
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/* Get server reply. */ |
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type = packet_read(); |
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switch (type) { |
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case SSH_SMSG_FAILURE: |
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/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */ |
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debug("Kerberos v4 authentication failed."); |
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return 0; |
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break; |
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case SSH_SMSG_AUTH_KERBEROS_RESPONSE: |
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/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */ |
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debug("Kerberos v4 authentication accepted."); |
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/* Get server's response. */ |
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reply = packet_get_string((u_int *) &auth.length); |
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if (auth.length >= MAX_KTXT_LEN) |
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fatal("Kerberos v4: Malformed response from server"); |
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memcpy(auth.dat, reply, auth.length); |
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xfree(reply); |
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packet_check_eom(); |
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/* |
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* If his response isn't properly encrypted with the session |
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* key, and the decrypted checksum fails to match, he's |
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* bogus. Bail out. |
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*/ |
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r = krb_rd_priv(auth.dat, auth.length, schedule, &cred.session, |
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&foreign, &local, &msg_data); |
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if (r != KSUCCESS) { |
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debug("Kerberos v4 krb_rd_priv failed: %s", |
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krb_err_txt[r]); |
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packet_disconnect("Kerberos v4 challenge failed!"); |
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} |
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/* Fetch the (incremented) checksum that we supplied in the request. */ |
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memcpy((char *)&cksum, (char *)msg_data.app_data, |
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sizeof(cksum)); |
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cksum = ntohl(cksum); |
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/* If it matches, we're golden. */ |
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if (cksum == checksum + 1) { |
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debug("Kerberos v4 challenge successful."); |
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return 1; |
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} else |
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packet_disconnect("Kerberos v4 challenge failed!"); |
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break; |
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default: |
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packet_disconnect("Protocol error on Kerberos v4 response: %d", type); |
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} |
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return 0; |
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} |
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#endif /* KRB4 */ |
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#ifdef KRB5 |
#ifdef KRB5 |
static int |
static int |
try_krb5_authentication(krb5_context *context, krb5_auth_context *auth_context) |
try_krb5_authentication(krb5_context *context, krb5_auth_context *auth_context) |
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} |
} |
#endif /* KRB5 */ |
#endif /* KRB5 */ |
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#ifdef AFS |
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static void |
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send_krb4_tgt(void) |
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{ |
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CREDENTIALS *creds; |
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struct stat st; |
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char buffer[4096], pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ]; |
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int problem, type; |
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/* Don't do anything if we don't have any tickets. */ |
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if (stat(tkt_string(), &st) < 0) |
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return; |
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creds = xmalloc(sizeof(*creds)); |
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problem = krb_get_tf_fullname(TKT_FILE, pname, pinst, prealm); |
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if (problem) |
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goto out; |
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problem = krb_get_cred("krbtgt", prealm, prealm, creds); |
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if (problem) |
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goto out; |
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if (time(0) > krb_life_to_time(creds->issue_date, creds->lifetime)) { |
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problem = RD_AP_EXP; |
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goto out; |
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} |
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creds_to_radix(creds, (u_char *)buffer, sizeof(buffer)); |
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packet_start(SSH_CMSG_HAVE_KERBEROS_TGT); |
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packet_put_cstring(buffer); |
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packet_send(); |
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packet_write_wait(); |
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type = packet_read(); |
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if (type == SSH_SMSG_SUCCESS) |
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debug("Kerberos v4 TGT forwarded (%s%s%s@%s).", |
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creds->pname, creds->pinst[0] ? "." : "", |
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creds->pinst, creds->realm); |
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else |
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debug("Kerberos v4 TGT rejected."); |
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xfree(creds); |
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return; |
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out: |
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debug("Kerberos v4 TGT passing failed: %s", krb_err_txt[problem]); |
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xfree(creds); |
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} |
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static void |
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send_afs_tokens(void) |
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{ |
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CREDENTIALS creds; |
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struct ViceIoctl parms; |
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struct ClearToken ct; |
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int i, type, len; |
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char buf[2048], *p, *server_cell; |
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char buffer[8192]; |
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/* Move over ktc_GetToken, here's something leaner. */ |
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for (i = 0; i < 100; i++) { /* just in case */ |
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parms.in = (char *) &i; |
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parms.in_size = sizeof(i); |
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parms.out = buf; |
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parms.out_size = sizeof(buf); |
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if (k_pioctl(0, VIOCGETTOK, &parms, 0) != 0) |
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break; |
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p = buf; |
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/* Get secret token. */ |
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memcpy(&creds.ticket_st.length, p, sizeof(u_int)); |
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if (creds.ticket_st.length > MAX_KTXT_LEN) |
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break; |
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p += sizeof(u_int); |
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memcpy(creds.ticket_st.dat, p, creds.ticket_st.length); |
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p += creds.ticket_st.length; |
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/* Get clear token. */ |
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memcpy(&len, p, sizeof(len)); |
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if (len != sizeof(struct ClearToken)) |
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break; |
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p += sizeof(len); |
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memcpy(&ct, p, len); |
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p += len; |
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p += sizeof(len); /* primary flag */ |
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server_cell = p; |
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/* Flesh out our credentials. */ |
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strlcpy(creds.service, "afs", sizeof(creds.service)); |
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creds.instance[0] = '\0'; |
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strlcpy(creds.realm, server_cell, REALM_SZ); |
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memcpy(creds.session, ct.HandShakeKey, DES_KEY_SZ); |
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creds.issue_date = ct.BeginTimestamp; |
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creds.lifetime = krb_time_to_life(creds.issue_date, |
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ct.EndTimestamp); |
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creds.kvno = ct.AuthHandle; |
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snprintf(creds.pname, sizeof(creds.pname), "AFS ID %d", ct.ViceId); |
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creds.pinst[0] = '\0'; |
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/* Encode token, ship it off. */ |
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if (creds_to_radix(&creds, (u_char *)buffer, |
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sizeof(buffer)) <= 0) |
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break; |
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packet_start(SSH_CMSG_HAVE_AFS_TOKEN); |
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packet_put_cstring(buffer); |
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packet_send(); |
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packet_write_wait(); |
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/* Roger, Roger. Clearance, Clarence. What's your vector, |
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Victor? */ |
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type = packet_read(); |
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if (type == SSH_SMSG_FAILURE) |
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debug("AFS token for cell %s rejected.", server_cell); |
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else if (type != SSH_SMSG_SUCCESS) |
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packet_disconnect("Protocol error on AFS token response: %d", type); |
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} |
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} |
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#endif /* AFS */ |
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/* |
/* |
* Tries to authenticate with any string-based challenge/response system. |
* Tries to authenticate with any string-based challenge/response system. |
* Note that the client code is not tied to s/key or TIS. |
* Note that the client code is not tied to s/key or TIS. |
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} |
} |
#endif /* KRB5 */ |
#endif /* KRB5 */ |
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#ifdef KRB4 |
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if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) && |
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options.kerberos_authentication) { |
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debug("Trying Kerberos v4 authentication."); |
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if (try_krb4_authentication()) { |
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type = packet_read(); |
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if (type == SSH_SMSG_SUCCESS) |
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goto success; |
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if (type != SSH_SMSG_FAILURE) |
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packet_disconnect("Protocol error: got %d in response to Kerberos v4 auth", type); |
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} |
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} |
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#endif /* KRB4 */ |
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/* |
/* |
* Use rhosts authentication if running in privileged socket and we |
* Use rhosts authentication if running in privileged socket and we |
* do not wish to remain anonymous. |
* do not wish to remain anonymous. |
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if (context) |
if (context) |
krb5_free_context(context); |
krb5_free_context(context); |
#endif |
#endif |
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#ifdef AFS |
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/* Try Kerberos v4 TGT passing if the server supports it. */ |
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if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) && |
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options.kerberos_tgt_passing) { |
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if (options.cipher == SSH_CIPHER_NONE) |
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logit("WARNING: Encryption is disabled! Ticket will be transmitted in the clear!"); |
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send_krb4_tgt(); |
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} |
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/* Try AFS token passing if the server supports it. */ |
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if ((supported_authentications & (1 << SSH_PASS_AFS_TOKEN)) && |
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options.afs_token_passing && k_hasafs()) { |
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if (options.cipher == SSH_CIPHER_NONE) |
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logit("WARNING: Encryption is disabled! Token will be transmitted in the clear!"); |
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send_afs_tokens(); |
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} |
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#endif /* AFS */ |
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return; /* need statement after label */ |
return; /* need statement after label */ |
} |
} |