diff options
| -rw-r--r-- | ChangeLog | 33 | ||||
| -rw-r--r-- | PROTOCOL | 23 | ||||
| -rw-r--r-- | PROTOCOL.agent | 24 | ||||
| -rw-r--r-- | PROTOCOL.certkeys | 191 | ||||
| -rw-r--r-- | addrmatch.c | 78 | ||||
| -rw-r--r-- | auth-options.c | 150 | ||||
| -rw-r--r-- | auth-options.h | 4 | ||||
| -rw-r--r-- | auth.h | 5 | ||||
| -rw-r--r-- | auth2-pubkey.c | 37 | ||||
| -rw-r--r-- | authfd.c | 24 | ||||
| -rw-r--r-- | dns.c | 8 | ||||
| -rw-r--r-- | dns.h | 6 | ||||
| -rw-r--r-- | hostfile.c | 31 | ||||
| -rw-r--r-- | hostfile.h | 4 | ||||
| -rw-r--r-- | kex.h | 5 | ||||
| -rw-r--r-- | kexdhs.c | 19 | ||||
| -rw-r--r-- | kexgexs.c | 20 | ||||
| -rw-r--r-- | key.c | 595 | ||||
| -rw-r--r-- | key.h | 32 | ||||
| -rw-r--r-- | match.h | 4 | ||||
| -rw-r--r-- | monitor.c | 5 | ||||
| -rw-r--r-- | myproposal.h | 6 | ||||
| -rw-r--r-- | servconf.c | 19 | ||||
| -rw-r--r-- | servconf.h | 5 | ||||
| -rw-r--r-- | ssh-add.c | 34 | ||||
| -rw-r--r-- | ssh-agent.c | 24 | ||||
| -rw-r--r-- | ssh-dss.c | 10 | ||||
| -rw-r--r-- | ssh-keygen.1 | 178 | ||||
| -rw-r--r-- | ssh-keygen.c | 433 | ||||
| -rw-r--r-- | ssh-rsa.c | 10 | ||||
| -rw-r--r-- | ssh.1 | 23 | ||||
| -rw-r--r-- | ssh.c | 71 | ||||
| -rw-r--r-- | ssh2.h | 5 | ||||
| -rw-r--r-- | sshconnect.c | 78 | ||||
| -rw-r--r-- | sshconnect2.c | 4 | ||||
| -rw-r--r-- | sshd.8 | 25 | ||||
| -rw-r--r-- | sshd.c | 117 | ||||
| -rw-r--r-- | sshd_config.5 | 12 |
38 files changed, 2164 insertions, 188 deletions
@@ -1,3 +1,36 @@ +20100226 + - OpenBSD CVS Sync + - djm@cvs.openbsd.org 2010/02/26 20:29:54 + [PROTOCOL PROTOCOL.agent PROTOCOL.certkeys addrmatch.c auth-options.c] + [auth-options.h auth.h auth2-pubkey.c authfd.c dns.c dns.h hostfile.c] + [hostfile.h kex.h kexdhs.c kexgexs.c key.c key.h match.h monitor.c] + [myproposal.h servconf.c servconf.h ssh-add.c ssh-agent.c ssh-dss.c] + [ssh-keygen.1 ssh-keygen.c ssh-rsa.c ssh.1 ssh.c ssh2.h sshconnect.c] + [sshconnect2.c sshd.8 sshd.c sshd_config.5] + Add support for certificate key types for users and hosts. + + OpenSSH certificate key types are not X.509 certificates, but a much + simpler format that encodes a public key, identity information and + some validity constraints and signs it with a CA key. CA keys are + regular SSH keys. This certificate style avoids the attack surface + of X.509 certificates and is very easy to deploy. + + Certified host keys allow automatic acceptance of new host keys + when a CA certificate is marked as trusted in ~/.ssh/known_hosts. + see VERIFYING HOST KEYS in ssh(1) for details. + + Certified user keys allow authentication of users when the signing + CA key is marked as trusted in authorized_keys. See "AUTHORIZED_KEYS + FILE FORMAT" in sshd(8) for details. + + Certificates are minted using ssh-keygen(1), documentation is in + the "CERTIFICATES" section of that manpage. + + Documentation on the format of certificates is in the file + PROTOCOL.certkeys + + feedback and ok markus@ + 20100224 - (djm) [pkcs11.h ssh-pkcs11-client.c ssh-pkcs11-helper.c ssh-pkcs11.c] [ssh-pkcs11.h] Add $OpenBSD$ RCS idents so we can sync portable @@ -31,7 +31,14 @@ The method is documented in: http://www.openssh.com/txt/draft-miller-secsh-compression-delayed-00.txt -3. connection: Channel write close extension "eow@openssh.com" +3. transport: New public key algorithms "ssh-rsa-cert-v00@openssh.com" and + "ssh-dsa-cert-v00@openssh.com" + +OpenSSH introduces two new public key algorithms to support certificate +authentication for users and hostkeys. These methods are documented in +the file PROTOCOL.certkeys + +4. connection: Channel write close extension "eow@openssh.com" The SSH connection protocol (rfc4254) provides the SSH_MSG_CHANNEL_EOF message to allow an endpoint to signal its peer that it will send no @@ -70,7 +77,7 @@ message is only sent to OpenSSH peers (identified by banner). Other SSH implementations may be whitelisted to receive this message upon request. -4. connection: disallow additional sessions extension +5. connection: disallow additional sessions extension "no-more-sessions@openssh.com" Most SSH connections will only ever request a single session, but a @@ -98,7 +105,7 @@ of this message, the no-more-sessions request is only sent to OpenSSH servers (identified by banner). Other SSH implementations may be whitelisted to receive this message upon request. -5. connection: Tunnel forward extension "tun@openssh.com" +6. connection: Tunnel forward extension "tun@openssh.com" OpenSSH supports layer 2 and layer 3 tunnelling via the "tun@openssh.com" channel type. This channel type supports forwarding of network packets @@ -159,7 +166,7 @@ The contents of the "data" field for layer 2 packets is: The "frame" field contains an IEEE 802.3 Ethernet frame, including header. -6. sftp: Reversal of arguments to SSH_FXP_SYMLINK +7. sftp: Reversal of arguments to SSH_FXP_SYMLINK When OpenSSH's sftp-server was implemented, the order of the arguments to the SSH_FXP_SYMLINK method was inadvertently reversed. Unfortunately, @@ -172,7 +179,7 @@ SSH_FXP_SYMLINK as follows: string targetpath string linkpath -7. sftp: Server extension announcement in SSH_FXP_VERSION +8. sftp: Server extension announcement in SSH_FXP_VERSION OpenSSH's sftp-server lists the extensions it supports using the standard extension announcement mechanism in the SSH_FXP_VERSION server @@ -193,7 +200,7 @@ ever changed in an incompatible way. The server MAY advertise the same extension with multiple versions (though this is unlikely). Clients MUST check the version number before attempting to use the extension. -8. sftp: Extension request "posix-rename@openssh.com" +9. sftp: Extension request "posix-rename@openssh.com" This operation provides a rename operation with POSIX semantics, which are different to those provided by the standard SSH_FXP_RENAME in @@ -210,7 +217,7 @@ rename(oldpath, newpath) and will respond with a SSH_FXP_STATUS message. This extension is advertised in the SSH_FXP_VERSION hello with version "1". -9. sftp: Extension requests "statvfs@openssh.com" and +10. sftp: Extension requests "statvfs@openssh.com" and "fstatvfs@openssh.com" These requests correspond to the statvfs and fstatvfs POSIX system @@ -251,4 +258,4 @@ The values of the f_flag bitmask are as follows: Both the "statvfs@openssh.com" and "fstatvfs@openssh.com" extensions are advertised in the SSH_FXP_VERSION hello with version "2". -$OpenBSD: PROTOCOL,v 1.14 2010/01/09 00:57:10 djm Exp $ +$OpenBSD: PROTOCOL,v 1.15 2010/02/26 20:29:54 djm Exp $ diff --git a/PROTOCOL.agent b/PROTOCOL.agent index 49adbdd5..b34fcd31 100644 --- a/PROTOCOL.agent +++ b/PROTOCOL.agent @@ -173,6 +173,15 @@ be added using the following request string key_comment constraint[] key_constraints +DSA certificates may be added with: + byte SSH2_AGENTC_ADD_IDENTITY or + SSH2_AGENTC_ADD_ID_CONSTRAINED + string "ssh-dss-cert-v00@openssh.com" + string certificate + mpint dsa_private_key + string key_comment + constraint[] key_constraints + RSA keys may be added with this request: byte SSH2_AGENTC_ADD_IDENTITY or @@ -187,6 +196,19 @@ RSA keys may be added with this request: string key_comment constraint[] key_constraints +RSA certificates may be added with this request: + + byte SSH2_AGENTC_ADD_IDENTITY or + SSH2_AGENTC_ADD_ID_CONSTRAINED + string "ssh-rsa-cert-v00@openssh.com" + string certificate + mpint rsa_d + mpint rsa_iqmp + mpint rsa_p + mpint rsa_q + string key_comment + constraint[] key_constraints + Note that the 'rsa_p' and 'rsa_q' parameters are sent in the reverse order to the protocol 1 add keys message. As with the corresponding protocol 1 "add key" request, the private key is overspecified to avoid @@ -513,4 +535,4 @@ Locking and unlocking affects both protocol 1 and protocol 2 keys. SSH_AGENT_CONSTRAIN_LIFETIME 1 SSH_AGENT_CONSTRAIN_CONFIRM 2 -$OpenBSD: PROTOCOL.agent,v 1.4 2008/07/01 23:12:47 stevesk Exp $ +$OpenBSD: PROTOCOL.agent,v 1.5 2010/02/26 20:29:54 djm Exp $ diff --git a/PROTOCOL.certkeys b/PROTOCOL.certkeys new file mode 100644 index 00000000..0b887a24 --- /dev/null +++ b/PROTOCOL.certkeys @@ -0,0 +1,191 @@ +This document describes a simple public-key certificate authentication +system for use by SSH. + +Background +---------- + +The SSH protocol currently supports a simple public key authentication +mechanism. Unlike other public key implementations, SSH eschews the +use of X.509 certificates and uses raw keys. This approach has some +benefits relating to simplicity of configuration and minimisation +of attack surface, but it does not support the important use-cases +of centrally managed, passwordless authentication and centrally +certified host keys. + +These protocol extensions build on the simple public key authentication +system already in SSH to allow certificate-based authentication. +The certificates used are not traditional X.509 certificates, with +numerous options and complex encoding rules, but something rather +more minimal: a key, some identity information and usage constraints +that have been signed with some other trusted key. + +A sshd server may be configured to allow authentication via certified +keys, by extending the existing ~/.ssh/authorized_keys mechanism +to allow specification of certification authority keys in addition +to raw user keys. The ssh client will support automatic verification +of acceptance of certified host keys, by adding a similar ability +to specify CA keys in ~/.ssh/known_hosts. + +Certified keys are represented using two new key types: +ssh-rsa-cert-v00@openssh.com and ssh-dss-cert-v00@openssh.com that +include certification information along with the public key that is used +to sign challenges. ssh-keygen performs the CA signing operation. + +Protocol extensions +------------------- + +The SSH wire protocol includes several extensibility mechanisms. +These modifications shall take advantage of namespaced public key +algorithm names to add support for certificate authentication without +breaking the protocol - implementations that do not support the +extensions will simply ignore them. + +Authentication using the new key formats described below proceeds +using the existing SSH "publickey" authentication method described +in RFC4252 section 7. + +New public key formats +---------------------- + +The ssh-rsa-cert-v00@openssh.com and ssh-dss-cert-v00@openssh.com key +types take a similar same high-level format (note: data types and +encoding are as per RFC4251 section 5). The serialised wire encoding of +these certificates is also used for storing them on disk. + +#define SSH_CERT_TYPE_USER 1 +#define SSH_CERT_TYPE_HOST 2 + +RSA certificate + + string "ssh-rsa-cert-v00@openssh.com" + mpint e + mpint n + uint32 type + string key id + string valid principals + uint64 valid after + uint64 valid before + string constraints + string nonce + string reserved + string signature key + string signature + +DSA certificate + + string "ssh-dss-cert-v00@openssh.com" + mpint p + mpint q + mpint g + mpint y + uint32 type + string key id + string valid principals + uint64 valid after + uint64 valid before + string constraints + string nonce + string reserved + string signature key + string signature + +e and n are the RSA exponent and public modulus respectively. + +p, q, g, y are the DSA parameters as described in FIPS-186-2. + +type specifies whether this certificate is for identification of a user +or a host using a SSH_CERT_TYPE_... value. + +key id is a free-form text field that is filled in by the CA at the time +of signing; the intention is that the contents of this field are used to +identify the identity principal in log messages. + +"valid principals" is a string containing zero or more principals as +strings packed inside it. These principals list the names for which this +certificate is valid; hostnames for SSH_CERT_TYPE_HOST certificates and +usernames for SSH_CERT_TYPE_USER certificates. As a special case, a +zero-length "valid principals" field means the certificate is valid for +any principal of the specified type. XXX DNS wildcards? + +"valid after" and "valid before" specify a validity period for the +certificate. Each represents a time in seconds since 1970-01-01 +00:00:00. A certificate is considered valid if: + valid after <= current time < valid before + +constraints is a set of zero or more key constraints encoded as below. + +The nonce field is a CA-provided random bitstring of arbitrary length +(but typically 16 or 32 bytes) included to make attacks that depend on +inducing collisions in the signature hash infeasible. + +The reserved field is current unused and is ignored in this version of +the protocol. + +signature key contains the CA key used to sign the certificate. +The valid key types for CA keys are ssh-rsa and ssh-dss. "Chained" +certificates, where the signature key type is a certificate type itself +are NOT supported. Note that it is possible for a RSA certificate key to +be signed by a DSS CA key and vice-versa. + +signature is computed over all preceding fields from the initial string +up to, and including the signature key. Signatures are computed and +encoded according to the rules defined for the CA's public key algorithm +(RFC4253 section 6.6 for ssh-rsa and ssh-dss). + +Constraints +----------- + +The constraints section of the certificate specifies zero or more +constraints on the certificates validity. The format of this field +is a sequence of zero or more tuples: + + string name + string data + +The name field identifies the constraint and the data field encodes +constraint-specific information (see below). All constraints are +"critical", if an implementation does not recognise a constraint +then the validating party should refuse to accept the certificate. + +The supported constraints and the contents and structure of their +data fields are: + +Name Format Description +----------------------------------------------------------------------------- +force-command string Specifies a command that is executed + (replacing any the user specified on the + ssh command-line) whenever this key is + used for authentication. + +permit-X11-forwarding empty Flag indicating that X11 forwarding + should be permitted. X11 forwarding will + be refused if this constraint is absent. + +permit-agent-forwarding empty Flag indicating that agent forwarding + should be allowed. Agent forwarding + must not be permitted unless this + constraint is present. + +permit-port-forwarding empty Flag indicating that port-forwarding + should be allowed. If this constraint is + not present then no port forwarding will + be allowed. + +permit-pty empty Flag indicating that PTY allocation + should be permitted. In the absence of + this constraint PTY allocation will be + disabled. + +permit-user-rc empty Flag indicating that execution of + ~/.ssh/rc should be permitted. Execution + of this script will not be permitted if + this constraint is not present. + +source-address string Comma-separated list of source addresses + from which this certificate is accepted + for authentication. Addresses are + specified in CIDR format (nn.nn.nn.nn/nn + or hhhh::hhhh/nn). + If this constraint is not present then + certificates may be presented from any + source address. diff --git a/addrmatch.c b/addrmatch.c index d39885b7..5b6773cc 100644 --- a/addrmatch.c +++ b/addrmatch.c @@ -1,4 +1,4 @@ -/* $OpenBSD: addrmatch.c,v 1.4 2008/12/10 03:55:20 stevesk Exp $ */ +/* $OpenBSD: addrmatch.c,v 1.5 2010/02/26 20:29:54 djm Exp $ */ /* * Copyright (c) 2004-2008 Damien Miller <djm@mindrot.org> @@ -126,6 +126,8 @@ addr_netmask(int af, u_int l, struct xaddr *n) switch (af) { case AF_INET: n->af = AF_INET; + if (l == 0) + return 0; n->v4.s_addr = htonl((0xffffffff << (32 - l)) & 0xffffffff); return 0; case AF_INET6: @@ -422,3 +424,77 @@ addr_match_list(const char *addr, const char *_list) return ret; } + +/* + * Match "addr" against list CIDR list "_list". Lexical wildcards and + * negation are not supported. If "addr" == NULL, will verify structure + * of "_list". + * + * Returns 1 on match found (never returned when addr == NULL). + * Returns 0 on if no match found, or no errors found when addr == NULL. + * Returns -1 on error + */ +int +addr_match_cidr_list(const char *addr, const char *_list) +{ + char *list, *cp, *o; + struct xaddr try_addr, match_addr; + u_int masklen; + int ret = 0, r; + + if (addr != NULL && addr_pton(addr, &try_addr) != 0) { + debug2("%s: couldn't parse address %.100s", __func__, addr); + return 0; + } + if ((o = list = strdup(_list)) == NULL) + return -1; + while ((cp = strsep(&list, ",")) != NULL) { + if (*cp == '\0') { + error("%s: empty entry in list \"%.100s\"", + __func__, o); + ret = -1; + break; + } + + /* + * NB. This function is called in pre-auth with untrusted data, + * so be extra paranoid about junk reaching getaddrino (via + * addr_pton_cidr). + */ + + /* Stop junk from reaching getaddrinfo. +3 is for masklen */ + if (strlen(cp) > INET6_ADDRSTRLEN + 3) { + error("%s: list entry \"%.100s\" too long", + __func__, cp); + ret = -1; + break; + } +#define VALID_CIDR_CHARS "0123456789abcdefABCDEF.:/" + if (strspn(cp, VALID_CIDR_CHARS) != strlen(cp)) { + error("%s: list entry \"%.100s\" contains invalid " + "characters", __func__, cp); + ret = -1; + } + + /* Prefer CIDR address matching */ + r = addr_pton_cidr(cp, &match_addr, &masklen); + if (r == -1) { + error("Invalid network entry \"%.100s\"", cp); + ret = -1; + break; + } else if (r == -2) { + error("Inconsistent mask length for " + "network \"%.100s\"", cp); + ret = -1; + break; + } else if (r == 0 && addr != NULL) { + if (addr_netmatch(&try_addr, &match_addr, + masklen) == 0) + ret = 1; + continue; + } + } + xfree(o); + + return ret; +} diff --git a/auth-options.c b/auth-options.c index ab085c23..396bda62 100644 --- a/auth-options.c +++ b/auth-options.c @@ -1,4 +1,4 @@ -/* $OpenBSD: auth-options.c,v 1.44 2009/01/22 10:09:16 djm Exp $ */ +/* $OpenBSD: auth-options.c,v 1.45 2010/02/26 20:29:54 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -44,6 +44,7 @@ int no_agent_forwarding_flag = 0; int no_x11_forwarding_flag = 0; int no_pty_flag = 0; int no_user_rc = 0; +int key_is_cert_authority = 0; /* "command=" option. */ char *forced_command = NULL; @@ -64,6 +65,7 @@ auth_clear_options(void) no_pty_flag = 0; no_x11_forwarding_flag = 0; no_user_rc = 0; + key_is_cert_authority = 0; while (custom_environment) { struct envstring *ce = custom_environment; custom_environment = ce->next; @@ -96,6 +98,12 @@ auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum) return 1; while (*opts && *opts != ' ' && *opts != '\t') { + cp = "cert-authority"; + if (strncasecmp(opts, cp, strlen(cp)) == 0) { + key_is_cert_authority = 1; + opts += strlen(cp); + goto next_option; + } cp = "no-port-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Port forwarding disabled."); @@ -374,3 +382,143 @@ bad_option: /* deny access */ return 0; } + +/* + * Set options from certificate constraints. These supersede user key options + * so this must be called after auth_parse_options(). + */ +int +auth_cert_constraints(Buffer *c_orig, struct passwd *pw) +{ + u_char *name = NULL, *data_blob = NULL; + u_int len; + Buffer c, data; + int ret = -1; + + int cert_no_port_forwarding_flag = 1; + int cert_no_agent_forwarding_flag = 1; + int cert_no_x11_forwarding_flag = 1; + int cert_no_pty_flag = 1; + int cert_no_user_rc = 1; + char *cert_forced_command = NULL; + int cert_source_address_done = 0; + + buffer_init(&data); + + /* Make copy to avoid altering original */ + buffer_init(&c); + buffer_append(&c, buffer_ptr(c_orig), buffer_len(c_orig)); + + while (buffer_len(&c) > 0) { + if ((name = buffer_get_string_ret(&c, NULL)) == NULL || + (data_blob = buffer_get_string_ret(&c, &len)) == NULL) { + error("Certificate constraints corrupt"); + goto out; + } + buffer_append(&data, data_blob, len); + debug3("found certificate constraint \"%.100s\" len %u", + name, len); + if (strcmp(name, "permit-X11-forwarding") == 0) + cert_no_x11_forwarding_flag = 0; + else if (strcmp(name, "permit-agent-forwarding") == 0) + cert_no_agent_forwarding_flag = 0; + else if (strcmp(name, "permit-port-forwarding") == 0) + cert_no_port_forwarding_flag = 0; + else if (strcmp(name, "permit-pty") == 0) + cert_no_pty_flag = 0; + else if (strcmp(name, "permit-user-rc") == 0) + cert_no_user_rc = 0; + else if (strcmp(name, "force-command") == 0) { + char *command = buffer_get_string_ret(&data, NULL); + + if (command == NULL) { + error("Certificate constraint \"%s\" corrupt", + name); + goto out; + } + if (cert_forced_command != NULL) { + error("Certificate has multiple " + "forced-command constraints"); + xfree(command); + goto out; + } + cert_forced_command = command; + } else if (strcmp(name, "source-address") == 0) { + char *allowed = buffer_get_string_ret(&data, NULL); + const char *remote_ip = get_remote_ipaddr(); + + if (allowed == NULL) { + error("Certificate constraint \"%s\" corrupt", + name); + goto out; + } + if (cert_source_address_done++) { + error("Certificate has multiple " + "source-address constraints"); + xfree(allowed); + goto out; + } + switch (addr_match_cidr_list(remote_ip, allowed)) { + case 1: + /* accepted */ + xfree(allowed); + break; + case 0: + /* no match */ + logit("Authentication tried for %.100s with " + "valid certificate but not from a " + "permitted host (ip=%.200s).", + pw->pw_name, remote_ip); + auth_debug_add("Your address '%.200s' is not " + "permitted to use this certificate for " + "login.", remote_ip); + xfree(allowed); + goto out; + case -1: + error("Certificate source-address contents " + "invalid"); + xfree(allowed); + goto out; + } + } else { + error("Certificate constraint \"%s\" is not supported", + name); + goto out; + } + + if (buffer_len(&data) != 0) { + error("Certificate constraint \"%s\" corrupt " + "(extra data)", name); + goto out; + } + buffer_clear(&data); + xfree(name); + xfree(data_blob); + name = data_blob = NULL; + } + + /* successfully parsed all constraints */ + ret = 0; + + no_port_forwarding_flag |= cert_no_port_forwarding_flag; + no_agent_forwarding_flag |= cert_no_agent_forwarding_flag; + no_x11_forwarding_flag |= cert_no_x11_forwarding_flag; + no_pty_flag |= cert_no_pty_flag; + no_user_rc |= cert_no_user_rc; + /* CA-specified forced command supersedes key option */ + if (cert_forced_command != NULL) { + if (forced_command != NULL) + xfree(forced_command); + forced_command = cert_forced_command; + } + + out: + if (name != NULL) + xfree(name); + if (data_blob != NULL) + xfree(data_blob); + buffer_free(&data); + buffer_free(&c); + return ret; +} + diff --git a/auth-options.h b/auth-options.h index 14488f72..694edc84 100644 --- a/auth-options.h +++ b/auth-options.h @@ -1,4 +1,4 @@ -/* $OpenBSD: auth-options.h,v 1.17 2008/03/26 21:28:14 djm Exp $ */ +/* $OpenBSD: auth-options.h,v 1.18 2010/02/26 20:29:54 djm Exp $ */ /* * Author: Tatu Ylonen <ylo@cs.hut.fi> @@ -30,8 +30,10 @@ extern int no_user_rc; extern char *forced_command; extern struct envstring *custom_environment; extern int forced_tun_device; +extern int key_is_cert_authority; int auth_parse_options(struct passwd *, char *, char *, u_long); void auth_clear_options(void); +int auth_cert_constraints(Buffer *, struct passwd *); #endif @@ -1,4 +1,4 @@ -/* $OpenBSD: auth.h,v 1.63 2009/08/15 18:56:34 fgsch Exp $ */ +/* $OpenBSD: auth.h,v 1.64 2010/02/26 20:29:54 djm Exp $ */ /* * Copyright (c) 2000 Markus Friedl. All rights reserved. @@ -178,7 +178,8 @@ check_key_in_hostfiles(struct passwd *, Key *, const char *, /* hostkey handling */ Key *get_hostkey_by_index(int); -Key *get_hostkey_by_type(int); +Key *get_hostkey_public_by_type(int); +Key *get_hostkey_private_by_type(int); int get_hostkey_index(Key *); int ssh1_session_key(BIGNUM *); diff --git a/auth2-pubkey.c b/auth2-pubkey.c index 2886f127..66ca5266 100644 --- a/auth2-pubkey.c +++ b/auth2-pubkey.c @@ -1,4 +1,4 @@ -/* $OpenBSD: auth2-pubkey.c,v 1.19 2008/07/03 21:46:58 otto Exp $ */ +/* $OpenBSD: auth2-pubkey.c,v 1.20 2010/02/26 20:29:54 djm Exp $ */ /* * Copyright (c) 2000 Markus Friedl. All rights reserved. * @@ -32,6 +32,8 @@ #include <pwd.h> #include <stdio.h> #include <stdarg.h> +#include <string.h> +#include <time.h> #include <unistd.h> #include "xmalloc.h" @@ -178,6 +180,7 @@ static int user_key_allowed2(struct passwd *pw, Key *key, char *file) { char line[SSH_MAX_PUBKEY_BYTES]; + const char *reason; int found_key = 0; FILE *f; u_long linenum = 0; @@ -196,11 +199,13 @@ user_key_allowed2(struct passwd *pw, Key *key, char *file) } found_key = 0; - found = key_new(key->type); + found = key_new(key_is_cert(key) ? KEY_UNSPEC : key->type); while (read_keyfile_line(f, file, line, sizeof(line), &linenum) != -1) { char *cp, *key_options = NULL; + auth_clear_options(); + /* Skip leading whitespace, empty and comment lines. */ for (cp = line; *cp == ' ' || *cp == '\t'; cp++) ; @@ -227,8 +232,32 @@ user_key_allowed2(struct passwd *pw, Key *key, char *file) continue; } } - if (key_equal(found, key) && - auth_parse_options(pw, key_options, file, linenum) == 1) { + if (auth_parse_options(pw, key_options, file, linenum) != 1) + continue; + if (key->type == KEY_RSA_CERT || key->type == KEY_DSA_CERT) { + if (!key_is_cert_authority) + continue; + if (!key_equal(found, key->cert->signature_key)) + continue; + debug("matching CA found: file %s, line %lu", + file, linenum); + fp = key_fingerprint(found, SSH_FP_MD5, + SSH_FP_HEX); + verbose("Found matching %s CA: %s", + key_type(found), fp); + xfree(fp); + if (key_cert_check_authority(key, 0, 0, pw->pw_name, + &reason) != 0) { + error("%s", reason); + auth_debug_add("%s", reason); + continue; |