diff options
Diffstat (limited to 'libs/libcurl/src/krb4.c')
-rw-r--r-- | libs/libcurl/src/krb4.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/libs/libcurl/src/krb4.c b/libs/libcurl/src/krb4.c new file mode 100644 index 0000000000..3d789621d8 --- /dev/null +++ b/libs/libcurl/src/krb4.c @@ -0,0 +1,440 @@ +/* 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 "curl_setup.h" + +#ifndef CURL_DISABLE_FTP +#ifdef HAVE_KRB4 + +#ifdef HAVE_NETDB_H +#include <netdb.h> +#endif +#include <krb.h> +#include <des.h> + +#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 = 0; + 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; + size_t base64_sz = 0; + + 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 + + result = Curl_base64_encode(conn->data, (char *)adat.dat, adat.length, + &p, &base64_sz); + if(result) { + Curl_failf(data, "base64-encoding: %s", curl_easy_strerror(result)); + 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; + result = Curl_base64_decode(p, &ptr, &len); + if(result) { + Curl_failf(data, "base64-decoding: %s", curl_easy_strerror(result)); + return AUTH_ERROR; + } + if(len > sizeof(adat.dat)-1) { + free(ptr); + ptr = NULL; + 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 = 0; + ssize_t nread; + enum protection_level save; + CURLcode result; + unsigned char *ptr; + size_t base64_sz = 0; + + 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; + result = Curl_base64_decode(p, &ptr, &tmp); + if(result) { + Curl_failf(conn->data, "base64-decoding: %s", curl_easy_strerror(result)); + return result; + } + if(tmp >= sizeof(tkt.dat)) { + free(ptr); + ptr = NULL; + 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)); + result = Curl_base64_encode(conn->data, (char *)tktcopy.dat, tktcopy.length, + &p, &base64_sz); + if(result) { + Curl_failf(conn->data, "base64-encoding: %s", curl_easy_strerror(result)); + krb4_set_command_prot(conn, save); + return result; + } + 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 */ |