| /* This source code was modified by Martin Hedenfalk <mhe@stacken.kth.se> for |
| * use in Curl. Martin's latest changes were done 2000-09-18. |
| * |
| * It has since been patched away like a madman by Daniel Stenberg to make it |
| * better applied to curl conditions, and to make it not use globals, pollute |
| * name space and more. |
| * |
| * Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska Högskolan |
| * (Royal Institute of Technology, Stockholm, Sweden). |
| * Copyright (c) 2004 - 2011 Daniel Stenberg |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * 3. Neither the name of the Institute nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| */ |
| |
| #include "setup.h" |
| |
| #ifndef CURL_DISABLE_FTP |
| #ifdef HAVE_KRB4 |
| |
| #ifdef HAVE_NETDB_H |
| #include <netdb.h> |
| #endif |
| #include <krb.h> |
| #include <des.h> |
| |
| #ifdef HAVE_UNISTD_H |
| #include <unistd.h> /* for getpid() */ |
| #endif |
| |
| #include "urldata.h" |
| #include "curl_base64.h" |
| #include "ftp.h" |
| #include "sendf.h" |
| #include "krb4.h" |
| #include "inet_ntop.h" |
| #include "curl_memory.h" |
| |
| /* The last #include file should be: */ |
| #include "memdebug.h" |
| |
| #define LOCAL_ADDR (&conn->local_addr) |
| #define REMOTE_ADDR conn->ip_addr->ai_addr |
| #define myctladdr LOCAL_ADDR |
| #define hisctladdr REMOTE_ADDR |
| |
| struct krb4_data { |
| des_cblock key; |
| des_key_schedule schedule; |
| char name[ANAME_SZ]; |
| char instance[INST_SZ]; |
| char realm[REALM_SZ]; |
| }; |
| |
| #ifndef HAVE_STRLCPY |
| /* if it ever goes non-static, make it Curl_ prefixed! */ |
| static size_t |
| strlcpy (char *dst, const char *src, size_t dst_sz) |
| { |
| size_t n; |
| char *p; |
| |
| for(p = dst, n = 0; |
| n + 1 < dst_sz && *src != '\0'; |
| ++p, ++src, ++n) |
| *p = *src; |
| *p = '\0'; |
| if(*src == '\0') |
| return n; |
| else |
| return n + strlen (src); |
| } |
| #else |
| size_t strlcpy (char *dst, const char *src, size_t dst_sz); |
| #endif |
| |
| static int |
| krb4_check_prot(void *app_data, int level) |
| { |
| app_data = NULL; /* prevent compiler warning */ |
| if(level == PROT_CONFIDENTIAL) |
| return -1; |
| return 0; |
| } |
| |
| static int |
| krb4_decode(void *app_data, void *buf, int len, int level, |
| struct connectdata *conn) |
| { |
| MSG_DAT m; |
| int e; |
| struct krb4_data *d = app_data; |
| |
| if(level == PROT_SAFE) |
| e = krb_rd_safe(buf, len, &d->key, |
| (struct sockaddr_in *)REMOTE_ADDR, |
| (struct sockaddr_in *)LOCAL_ADDR, &m); |
| else |
| e = krb_rd_priv(buf, len, d->schedule, &d->key, |
| (struct sockaddr_in *)REMOTE_ADDR, |
| (struct sockaddr_in *)LOCAL_ADDR, &m); |
| if(e) { |
| struct SessionHandle *data = conn->data; |
| infof(data, "krb4_decode: %s\n", krb_get_err_text(e)); |
| return -1; |
| } |
| memmove(buf, m.app_data, m.app_length); |
| return m.app_length; |
| } |
| |
| static int |
| krb4_overhead(void *app_data, int level, int len) |
| { |
| /* no arguments are used, just init them to prevent compiler warnings */ |
| app_data = NULL; |
| level = 0; |
| len = 0; |
| return 31; |
| } |
| |
| static int |
| krb4_encode(void *app_data, const void *from, int length, int level, void **to, |
| struct connectdata *conn) |
| { |
| struct krb4_data *d = app_data; |
| *to = malloc(length + 31); |
| if(!*to) |
| return -1; |
| if(level == PROT_SAFE) |
| /* NOTE that the void* cast is safe, krb_mk_safe/priv don't modify the |
| * input buffer |
| */ |
| return krb_mk_safe((void*)from, *to, length, &d->key, |
| (struct sockaddr_in *)LOCAL_ADDR, |
| (struct sockaddr_in *)REMOTE_ADDR); |
| else if(level == PROT_PRIVATE) |
| return krb_mk_priv((void*)from, *to, length, d->schedule, &d->key, |
| (struct sockaddr_in *)LOCAL_ADDR, |
| (struct sockaddr_in *)REMOTE_ADDR); |
| else |
| return -1; |
| } |
| |
| static int |
| mk_auth(struct krb4_data *d, KTEXT adat, |
| const char *service, char *host, int checksum) |
| { |
| int ret; |
| CREDENTIALS cred; |
| char sname[SNAME_SZ], inst[INST_SZ], realm[REALM_SZ]; |
| |
| strlcpy(sname, service, sizeof(sname)); |
| strlcpy(inst, krb_get_phost(host), sizeof(inst)); |
| strlcpy(realm, krb_realmofhost(host), sizeof(realm)); |
| ret = krb_mk_req(adat, sname, inst, realm, checksum); |
| if(ret) |
| return ret; |
| strlcpy(sname, service, sizeof(sname)); |
| strlcpy(inst, krb_get_phost(host), sizeof(inst)); |
| strlcpy(realm, krb_realmofhost(host), sizeof(realm)); |
| ret = krb_get_cred(sname, inst, realm, &cred); |
| memmove(&d->key, &cred.session, sizeof(des_cblock)); |
| des_key_sched(&d->key, d->schedule); |
| memset(&cred, 0, sizeof(cred)); |
| return ret; |
| } |
| |
| #ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM |
| int krb_get_our_ip_for_realm(char *, struct in_addr *); |
| #endif |
| |
| static int |
| krb4_auth(void *app_data, struct connectdata *conn) |
| { |
| int ret; |
| char *p; |
| unsigned char *ptr; |
| size_t len; |
| KTEXT_ST adat; |
| MSG_DAT msg_data; |
| int checksum; |
| u_int32_t cs; |
| struct krb4_data *d = app_data; |
| char *host = conn->host.name; |
| ssize_t nread; |
| int l = sizeof(conn->local_addr); |
| struct SessionHandle *data = conn->data; |
| CURLcode result; |
| |
| if(getsockname(conn->sock[FIRSTSOCKET], |
| (struct sockaddr *)LOCAL_ADDR, &l) < 0) |
| perror("getsockname()"); |
| |
| checksum = getpid(); |
| ret = mk_auth(d, &adat, "ftp", host, checksum); |
| if(ret == KDC_PR_UNKNOWN) |
| ret = mk_auth(d, &adat, "rcmd", host, checksum); |
| if(ret) { |
| infof(data, "%s\n", krb_get_err_text(ret)); |
| return AUTH_CONTINUE; |
| } |
| |
| #ifdef HAVE_KRB_GET_OUR_IP_FOR_REALM |
| if(krb_get_config_bool("nat_in_use")) { |
| struct sockaddr_in *localaddr = (struct sockaddr_in *)LOCAL_ADDR; |
| struct in_addr natAddr; |
| |
| if(krb_get_our_ip_for_realm(krb_realmofhost(host), |
| &natAddr) != KSUCCESS |
| && krb_get_our_ip_for_realm(NULL, &natAddr) != KSUCCESS) |
| infof(data, "Can't get address for realm %s\n", |
| krb_realmofhost(host)); |
| else { |
| if(natAddr.s_addr != localaddr->sin_addr.s_addr) { |
| char addr_buf[128]; |
| if(Curl_inet_ntop(AF_INET, natAddr, addr_buf, sizeof(addr_buf))) |
| infof(data, "Using NAT IP address (%s) for kerberos 4\n", addr_buf); |
| localaddr->sin_addr = natAddr; |
| } |
| } |
| } |
| #endif |
| |
| if(Curl_base64_encode(conn->data, (char *)adat.dat, adat.length, &p) < 1) { |
| Curl_failf(data, "Out of memory base64-encoding"); |
| return AUTH_CONTINUE; |
| } |
| |
| result = Curl_ftpsendf(conn, "ADAT %s", p); |
| |
| free(p); |
| |
| if(result) |
| return -2; |
| |
| if(Curl_GetFTPResponse(&nread, conn, NULL)) |
| return -1; |
| |
| if(data->state.buffer[0] != '2') { |
| Curl_failf(data, "Server didn't accept auth data"); |
| return AUTH_ERROR; |
| } |
| |
| p = strstr(data->state.buffer, "ADAT="); |
| if(!p) { |
| Curl_failf(data, "Remote host didn't send adat reply"); |
| return AUTH_ERROR; |
| } |
| p += 5; |
| len = Curl_base64_decode(p, &ptr); |
| if(len > sizeof(adat.dat)-1) { |
| free(ptr); |
| len=0; |
| } |
| if(!len || !ptr) { |
| Curl_failf(data, "Failed to decode base64 from server"); |
| return AUTH_ERROR; |
| } |
| memcpy((char *)adat.dat, ptr, len); |
| free(ptr); |
| adat.length = len; |
| ret = krb_rd_safe(adat.dat, adat.length, &d->key, |
| (struct sockaddr_in *)hisctladdr, |
| (struct sockaddr_in *)myctladdr, &msg_data); |
| if(ret) { |
| Curl_failf(data, "Error reading reply from server: %s", |
| krb_get_err_text(ret)); |
| return AUTH_ERROR; |
| } |
| krb_get_int(msg_data.app_data, &cs, 4, 0); |
| if(cs - checksum != 1) { |
| Curl_failf(data, "Bad checksum returned from server"); |
| return AUTH_ERROR; |
| } |
| return AUTH_OK; |
| } |
| |
| struct Curl_sec_client_mech Curl_krb4_client_mech = { |
| "KERBEROS_V4", |
| sizeof(struct krb4_data), |
| NULL, /* init */ |
| krb4_auth, |
| NULL, /* end */ |
| krb4_check_prot, |
| krb4_overhead, |
| krb4_encode, |
| krb4_decode |
| }; |
| |
| static enum protection_level |
| krb4_set_command_prot(struct connectdata *conn, enum protection_level level) |
| { |
| enum protection_level old = conn->command_prot; |
| DEBUGASSERT(level > PROT_NONE && level < PROT_LAST); |
| conn->command_prot = level; |
| return old; |
| } |
| |
| CURLcode Curl_krb_kauth(struct connectdata *conn) |
| { |
| des_cblock key; |
| des_key_schedule schedule; |
| KTEXT_ST tkt, tktcopy; |
| char *name; |
| char *p; |
| char passwd[100]; |
| size_t tmp; |
| ssize_t nread; |
| enum protection_level save; |
| CURLcode result; |
| unsigned char *ptr; |
| |
| save = krb4_set_command_prot(conn, PROT_PRIVATE); |
| |
| result = Curl_ftpsendf(conn, "SITE KAUTH %s", conn->user); |
| |
| if(result) |
| return result; |
| |
| result = Curl_GetFTPResponse(&nread, conn, NULL); |
| if(result) |
| return result; |
| |
| if(conn->data->state.buffer[0] != '3') { |
| krb4_set_command_prot(conn, save); |
| return CURLE_FTP_WEIRD_SERVER_REPLY; |
| } |
| |
| p = strstr(conn->data->state.buffer, "T="); |
| if(!p) { |
| Curl_failf(conn->data, "Bad reply from server"); |
| krb4_set_command_prot(conn, save); |
| return CURLE_FTP_WEIRD_SERVER_REPLY; |
| } |
| |
| p += 2; |
| tmp = Curl_base64_decode(p, &ptr); |
| if(tmp >= sizeof(tkt.dat)) { |
| free(ptr); |
| tmp=0; |
| } |
| if(!tmp || !ptr) { |
| Curl_failf(conn->data, "Failed to decode base64 in reply"); |
| krb4_set_command_prot(conn, save); |
| return CURLE_FTP_WEIRD_SERVER_REPLY; |
| } |
| memcpy((char *)tkt.dat, ptr, tmp); |
| free(ptr); |
| tkt.length = tmp; |
| tktcopy.length = tkt.length; |
| |
| p = strstr(conn->data->state.buffer, "P="); |
| if(!p) { |
| Curl_failf(conn->data, "Bad reply from server"); |
| krb4_set_command_prot(conn, save); |
| return CURLE_FTP_WEIRD_SERVER_REPLY; |
| } |
| name = p + 2; |
| for(; *p && *p != ' ' && *p != '\r' && *p != '\n'; p++); |
| *p = 0; |
| |
| des_string_to_key (conn->passwd, &key); |
| des_key_sched(&key, schedule); |
| |
| des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat, |
| tkt.length, |
| schedule, &key, DES_DECRYPT); |
| if(strcmp ((char*)tktcopy.dat + 8, |
| KRB_TICKET_GRANTING_TICKET) != 0) { |
| afs_string_to_key(passwd, |
| krb_realmofhost(conn->host.name), |
| &key); |
| des_key_sched(&key, schedule); |
| des_pcbc_encrypt((void *)tkt.dat, (void *)tktcopy.dat, |
| tkt.length, |
| schedule, &key, DES_DECRYPT); |
| } |
| memset(key, 0, sizeof(key)); |
| memset(schedule, 0, sizeof(schedule)); |
| memset(passwd, 0, sizeof(passwd)); |
| if(Curl_base64_encode(conn->data, (char *)tktcopy.dat, tktcopy.length, &p) |
| < 1) { |
| failf(conn->data, "Out of memory base64-encoding."); |
| krb4_set_command_prot(conn, save); |
| return CURLE_OUT_OF_MEMORY; |
| } |
| memset (tktcopy.dat, 0, tktcopy.length); |
| |
| result = Curl_ftpsendf(conn, "SITE KAUTH %s %s", name, p); |
| free(p); |
| if(result) |
| return result; |
| |
| result = Curl_GetFTPResponse(&nread, conn, NULL); |
| if(result) |
| return result; |
| krb4_set_command_prot(conn, save); |
| |
| return CURLE_OK; |
| } |
| |
| #endif /* HAVE_KRB4 */ |
| #endif /* CURL_DISABLE_FTP */ |