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Diffstat (limited to '')
| -rw-r--r-- | openbsd-compat/port-aix.c | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/openbsd-compat/port-aix.c b/openbsd-compat/port-aix.c new file mode 100644 index 0000000..2ac9bad --- /dev/null +++ b/openbsd-compat/port-aix.c @@ -0,0 +1,483 @@ +/* + * + * Copyright (c) 2001 Gert Doering. All rights reserved. + * Copyright (c) 2003,2004,2005,2006 Darren Tucker. 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 "includes.h" + +#ifdef _AIX + +#include "xmalloc.h" +#include "sshbuf.h" +#include "ssherr.h" +#include "sshkey.h" +#include "hostfile.h" +#include "auth.h" +#include "ssh.h" +#include "ssh_api.h" +#include "log.h" + +#include <errno.h> +#if defined(HAVE_NETDB_H) +# include <netdb.h> +#endif +#include <uinfo.h> +#include <stdarg.h> +#include <string.h> +#include <unistd.h> +#include <sys/socket.h> + +#ifdef WITH_AIXAUTHENTICATE +# include <login.h> +# include <userpw.h> +# if defined(HAVE_SYS_AUDIT_H) && defined(AIX_LOGINFAILED_4ARG) +# include <sys/audit.h> +# endif +# include <usersec.h> +#endif + +#include "port-aix.h" + +static char *lastlogin_msg = NULL; + +# ifdef HAVE_SETAUTHDB +static char old_registry[REGISTRY_SIZE] = ""; +# endif + +/* + * AIX has a "usrinfo" area where logname and other stuff is stored - + * a few applications actually use this and die if it's not set + * + * NOTE: TTY= should be set, but since no one uses it and it's hard to + * acquire due to privsep code. We will just drop support. + */ +void +aix_usrinfo(struct passwd *pw) +{ + u_int i; + size_t len; + char *cp; + + len = sizeof("LOGNAME= NAME= ") + (2 * strlen(pw->pw_name)); + cp = xmalloc(len); + + i = snprintf(cp, len, "LOGNAME=%s%cNAME=%s%c", pw->pw_name, '\0', + pw->pw_name, '\0'); + if (usrinfo(SETUINFO, cp, i) == -1) + fatal("Couldn't set usrinfo: %s", strerror(errno)); + debug3("AIX/UsrInfo: set len %d", i); + + free(cp); +} + +# ifdef WITH_AIXAUTHENTICATE +/* + * Remove embedded newlines in string (if any). + * Used before logging messages returned by AIX authentication functions + * so the message is logged on one line. + */ +void +aix_remove_embedded_newlines(char *p) +{ + if (p == NULL) + return; + + for (; *p; p++) { + if (*p == '\n') + *p = ' '; + } + /* Remove trailing whitespace */ + if (*--p == ' ') + *p = '\0'; +} + +/* + * Test specifically for the case where SYSTEM == NONE and AUTH1 contains + * anything other than NONE or SYSTEM, which indicates that the admin has + * configured the account for purely AUTH1-type authentication. + * + * Since authenticate() doesn't check AUTH1, and sshd can't sanely support + * AUTH1 itself, in such a case authenticate() will allow access without + * authentation, which is almost certainly not what the admin intends. + * + * (The native tools, eg login, will process the AUTH1 list in addition to + * the SYSTEM list by using ckuserID(), however ckuserID() and AUTH1 methods + * have been deprecated since AIX 4.2.x and would be very difficult for sshd + * to support. + * + * Returns 0 if an unsupportable combination is found, 1 otherwise. + */ +static int +aix_valid_authentications(const char *user) +{ + char *auth1, *sys, *p; + int valid = 1; + + if (getuserattr((char *)user, S_AUTHSYSTEM, &sys, SEC_CHAR) != 0) { + logit("Can't retrieve attribute SYSTEM for %s: %.100s", + user, strerror(errno)); + return 0; + } + + debug3("AIX SYSTEM attribute %s", sys); + if (strcmp(sys, "NONE") != 0) + return 1; /* not "NONE", so is OK */ + + if (getuserattr((char *)user, S_AUTH1, &auth1, SEC_LIST) != 0) { + logit("Can't retrieve attribute auth1 for %s: %.100s", + user, strerror(errno)); + return 0; + } + + p = auth1; + /* A SEC_LIST is concatenated strings, ending with two NULs. */ + while (p[0] != '\0' && p[1] != '\0') { + debug3("AIX auth1 attribute list member %s", p); + if (strcmp(p, "NONE") != 0 && strcmp(p, "SYSTEM")) { + logit("Account %s has unsupported auth1 value '%s'", + user, p); + valid = 0; + } + p += strlen(p) + 1; + } + + return (valid); +} + +/* + * Do authentication via AIX's authenticate routine. We loop until the + * reenter parameter is 0, but normally authenticate is called only once. + * + * Note: this function returns 1 on success, whereas AIX's authenticate() + * returns 0. + */ +int +sys_auth_passwd(struct ssh *ssh, const char *password) +{ + Authctxt *ctxt = ssh->authctxt; + char *authmsg = NULL, *msg = NULL, *name = ctxt->pw->pw_name; + int r, authsuccess = 0, expired, reenter, result; + + do { + result = authenticate((char *)name, (char *)password, &reenter, + &authmsg); + aix_remove_embedded_newlines(authmsg); + debug3("AIX/authenticate result %d, authmsg %.100s", result, + authmsg); + } while (reenter); + + if (!aix_valid_authentications(name)) + result = -1; + + if (result == 0) { + authsuccess = 1; + + /* + * Record successful login. We don't have a pty yet, so just + * label the line as "ssh" + */ + aix_setauthdb(name); + + /* + * Check if the user's password is expired. + */ + expired = passwdexpired(name, &msg); + if (msg && *msg) { + if ((r = sshbuf_put(ctxt->loginmsg, + msg, strlen(msg))) != 0) + fatal("%s: buffer error: %s", + __func__, ssh_err(r)); + aix_remove_embedded_newlines(msg); + } + debug3("AIX/passwdexpired returned %d msg %.100s", expired, msg); + + switch (expired) { + case 0: /* password not expired */ + break; + case 1: /* expired, password change required */ + ctxt->force_pwchange = 1; + break; + default: /* user can't change(2) or other error (-1) */ + logit("Password can't be changed for user %s: %.100s", + name, msg); + free(msg); + authsuccess = 0; + } + + aix_restoreauthdb(); + } + + free(authmsg); + + return authsuccess; +} + +/* + * Check if specified account is permitted to log in. + * Returns 1 if login is allowed, 0 if not allowed. + */ +int +sys_auth_allowed_user(struct passwd *pw, struct sshbuf *loginmsg) +{ + char *msg = NULL; + int r, result, permitted = 0; + struct stat st; + + /* + * Don't perform checks for root account (PermitRootLogin controls + * logins via ssh) or if running as non-root user (since + * loginrestrictions will always fail due to insufficient privilege). + */ + if (pw->pw_uid == 0 || geteuid() != 0) { + debug3("%s: not checking", __func__); + return 1; + } + + result = loginrestrictions(pw->pw_name, S_RLOGIN, NULL, &msg); + if (result == 0) + permitted = 1; + /* + * If restricted because /etc/nologin exists, the login will be denied + * in session.c after the nologin message is sent, so allow for now + * and do not append the returned message. + */ + if (result == -1 && errno == EPERM && stat(_PATH_NOLOGIN, &st) == 0) + permitted = 1; + else if (msg != NULL) { + if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0) + fatal("%s: buffer error: %s", __func__, ssh_err(r)); + } + if (msg == NULL) + msg = xstrdup("(none)"); + aix_remove_embedded_newlines(msg); + debug3("AIX/loginrestrictions returned %d msg %.100s", result, msg); + + if (!permitted) + logit("Login restricted for %s: %.100s", pw->pw_name, msg); + free(msg); + return permitted; +} + +int +sys_auth_record_login(const char *user, const char *host, const char *ttynm, + struct sshbuf *loginmsg) +{ + char *msg = NULL; + int success = 0; + + aix_setauthdb(user); + if (loginsuccess((char *)user, (char *)host, (char *)ttynm, &msg) == 0) { + success = 1; + if (msg != NULL) { + debug("AIX/loginsuccess: msg %s", msg); + if (lastlogin_msg == NULL) + lastlogin_msg = msg; + } + } + aix_restoreauthdb(); + return (success); +} + +char * +sys_auth_get_lastlogin_msg(const char *user, uid_t uid) +{ + char *msg = lastlogin_msg; + + lastlogin_msg = NULL; + return msg; +} + +# ifdef CUSTOM_FAILED_LOGIN +/* + * record_failed_login: generic "login failed" interface function + */ +void +record_failed_login(struct ssh *ssh, const char *user, const char *hostname, + const char *ttyname) +{ + if (geteuid() != 0) + return; + + aix_setauthdb(user); +# ifdef AIX_LOGINFAILED_4ARG + loginfailed((char *)user, (char *)hostname, (char *)ttyname, + AUDIT_FAIL_AUTH); +# else + loginfailed((char *)user, (char *)hostname, (char *)ttyname); +# endif + aix_restoreauthdb(); +} +# endif /* CUSTOM_FAILED_LOGIN */ + +/* + * If we have setauthdb, retrieve the password registry for the user's + * account then feed it to setauthdb. This will mean that subsequent AIX auth + * functions will only use the specified loadable module. If we don't have + * setauthdb this is a no-op. + */ +void +aix_setauthdb(const char *user) +{ +# ifdef HAVE_SETAUTHDB + char *registry; + + if (setuserdb(S_READ) == -1) { + debug3("%s: Could not open userdb to read", __func__); + return; + } + + if (getuserattr((char *)user, S_REGISTRY, ®istry, SEC_CHAR) == 0) { + if (setauthdb(registry, old_registry) == 0) + debug3("AIX/setauthdb set registry '%s'", registry); + else + debug3("AIX/setauthdb set registry '%s' failed: %s", + registry, strerror(errno)); + } else + debug3("%s: Could not read S_REGISTRY for user: %s", __func__, + strerror(errno)); + enduserdb(); +# endif /* HAVE_SETAUTHDB */ +} + +/* + * Restore the user's registry settings from old_registry. + * Note that if the first aix_setauthdb fails, setauthdb("") is still safe + * (it restores the system default behaviour). If we don't have setauthdb, + * this is a no-op. + */ +void +aix_restoreauthdb(void) +{ +# ifdef HAVE_SETAUTHDB + if (setauthdb(old_registry, NULL) == 0) + debug3("%s: restoring old registry '%s'", __func__, + old_registry); + else + debug3("%s: failed to restore old registry %s", __func__, + old_registry); +# endif /* HAVE_SETAUTHDB */ +} + +# endif /* WITH_AIXAUTHENTICATE */ + +# ifdef USE_AIX_KRB_NAME +/* + * aix_krb5_get_principal_name: returns the user's kerberos client principal + * name if configured, otherwise NULL. Caller must free returned string. + */ +char * +aix_krb5_get_principal_name(const char *const_pw_name) +{ + char *pw_name = (char *)const_pw_name; + char *authname = NULL, *authdomain = NULL, *principal = NULL; + + setuserdb(S_READ); + if (getuserattr(pw_name, S_AUTHDOMAIN, &authdomain, SEC_CHAR) != 0) + debug("AIX getuserattr S_AUTHDOMAIN: %s", strerror(errno)); + if (getuserattr(pw_name, S_AUTHNAME, &authname, SEC_CHAR) != 0) + debug("AIX getuserattr S_AUTHNAME: %s", strerror(errno)); + + if (authdomain != NULL) + xasprintf(&principal, "%s@%s", authname ? authname : pw_name, + authdomain); + else if (authname != NULL) + principal = xstrdup(authname); + enduserdb(); + return principal; +} +# endif /* USE_AIX_KRB_NAME */ + +# if defined(AIX_GETNAMEINFO_HACK) && !defined(BROKEN_ADDRINFO) +# undef getnameinfo +/* + * For some reason, AIX's getnameinfo will refuse to resolve the all-zeros + * IPv6 address into its textual representation ("::"), so we wrap it + * with a function that will. + */ +int +sshaix_getnameinfo(const struct sockaddr *sa, size_t salen, char *host, + size_t hostlen, char *serv, size_t servlen, int flags) +{ + struct sockaddr_in6 *sa6; + u_int32_t *a6; + + if (flags & (NI_NUMERICHOST|NI_NUMERICSERV) && + sa->sa_family == AF_INET6) { + sa6 = (struct sockaddr_in6 *)sa; + a6 = sa6->sin6_addr.u6_addr.u6_addr32; + + if (a6[0] == 0 && a6[1] == 0 && a6[2] == 0 && a6[3] == 0) { + strlcpy(host, "::", hostlen); + snprintf(serv, servlen, "%d", sa6->sin6_port); + return 0; + } + } + return getnameinfo(sa, salen, host, hostlen, serv, servlen, flags); +} +# endif /* AIX_GETNAMEINFO_HACK */ + +# if defined(USE_GETGRSET) +# include <stdlib.h> +int +getgrouplist(const char *user, gid_t pgid, gid_t *groups, int *grpcnt) +{ + char *cp, *grplist, *grp; + gid_t gid; + int ret = 0, ngroups = 0, maxgroups; + long long ll; + + maxgroups = *grpcnt; + + if ((cp = grplist = getgrset(user)) == NULL) + return -1; + + /* handle zero-length case */ + if (maxgroups <= 0) { + *grpcnt = 0; + return -1; + } + + /* copy primary group */ + groups[ngroups++] = pgid; + + /* copy each entry from getgrset into group list */ + while ((grp = strsep(&grplist, ",")) != NULL) { + ll = strtoll(grp, NULL, 10); + if (ngroups >= maxgroups || ll < 0 || ll > UID_MAX) { + ret = -1; + goto out; + } + gid = (gid_t)ll; + if (gid == pgid) + continue; /* we have already added primary gid */ + groups[ngroups++] = gid; + } +out: + free(cp); + *grpcnt = ngroups; + return ret; +} +# endif /* USE_GETGRSET */ + +#endif /* _AIX */ |