From f6d9e2218998559cb67aad55d3f4a0bf53600c41 Mon Sep 17 00:00:00 2001 From: Damien Miller Date: Sun, 18 Jun 2000 14:50:44 +1000 Subject: - OpenBSD CVS updates: - deraadt@cvs.openbsd.org 2000/06/17 09:58:46 [channels.c] everyone says "nix it" (remove protocol 2 debugging message) - markus@cvs.openbsd.org 2000/06/17 13:24:34 [sshconnect.c] allow extended server banners - markus@cvs.openbsd.org 2000/06/17 14:30:10 [sshconnect.c] missing atomicio, typo - jakob@cvs.openbsd.org 2000/06/17 16:52:34 [servconf.c servconf.h session.c sshd.8 sshd_config] add support for ssh v2 subsystems. ok markus@. - deraadt@cvs.openbsd.org 2000/06/17 18:57:48 [readconf.c servconf.c] include = in WHITESPACE; markus ok - markus@cvs.openbsd.org 2000/06/17 19:09:10 [auth2.c] implement bug compatibility with ssh-2.0.13 pubkey, server side - markus@cvs.openbsd.org 2000/06/17 21:00:28 [compat.c] initial support for ssh.com's 2.2.0 - markus@cvs.openbsd.org 2000/06/17 21:16:09 [scp.c] typo - markus@cvs.openbsd.org 2000/06/17 22:05:02 [auth-rsa.c auth2.c serverloop.c session.c auth-options.c auth-options.h] split auth-rsa option parsing into auth-options add options support to authorized_keys2 - markus@cvs.openbsd.org 2000/06/17 22:42:54 [session.c] typo --- auth-options.c | 208 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 208 insertions(+) create mode 100644 auth-options.c (limited to 'auth-options.c') diff --git a/auth-options.c b/auth-options.c new file mode 100644 index 000000000..7ebbb7661 --- /dev/null +++ b/auth-options.c @@ -0,0 +1,208 @@ +#include "includes.h" +RCSID("$Id: auth-options.c,v 1.1 2000/06/18 04:50:44 djm Exp $"); + +#include "ssh.h" +#include "packet.h" +#include "xmalloc.h" +#include "match.h" + +/* Flags set authorized_keys flags */ +int no_port_forwarding_flag = 0; +int no_agent_forwarding_flag = 0; +int no_x11_forwarding_flag = 0; +int no_pty_flag = 0; + +/* "command=" option. */ +char *forced_command = NULL; + +/* "environment=" options. */ +struct envstring *custom_environment = NULL; + +/* return 1 if access is granted, 0 if not. side effect: sets key option flags */ +int +auth_parse_options(struct passwd *pw, char *options, unsigned long linenum) +{ + const char *cp; + if (!options) + return 1; + while (*options && *options != ' ' && *options != '\t') { + cp = "no-port-forwarding"; + if (strncmp(options, cp, strlen(cp)) == 0) { + packet_send_debug("Port forwarding disabled."); + no_port_forwarding_flag = 1; + options += strlen(cp); + goto next_option; + } + cp = "no-agent-forwarding"; + if (strncmp(options, cp, strlen(cp)) == 0) { + packet_send_debug("Agent forwarding disabled."); + no_agent_forwarding_flag = 1; + options += strlen(cp); + goto next_option; + } + cp = "no-X11-forwarding"; + if (strncmp(options, cp, strlen(cp)) == 0) { + packet_send_debug("X11 forwarding disabled."); + no_x11_forwarding_flag = 1; + options += strlen(cp); + goto next_option; + } + cp = "no-pty"; + if (strncmp(options, cp, strlen(cp)) == 0) { + packet_send_debug("Pty allocation disabled."); + no_pty_flag = 1; + options += strlen(cp); + goto next_option; + } + cp = "command=\""; + if (strncmp(options, cp, strlen(cp)) == 0) { + int i; + options += strlen(cp); + forced_command = xmalloc(strlen(options) + 1); + i = 0; + while (*options) { + if (*options == '"') + break; + if (*options == '\\' && options[1] == '"') { + options += 2; + forced_command[i++] = '"'; + continue; + } + forced_command[i++] = *options++; + } + if (!*options) { + debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + packet_send_debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + continue; + } + forced_command[i] = 0; + packet_send_debug("Forced command: %.900s", forced_command); + options++; + goto next_option; + } + cp = "environment=\""; + if (strncmp(options, cp, strlen(cp)) == 0) { + int i; + char *s; + struct envstring *new_envstring; + options += strlen(cp); + s = xmalloc(strlen(options) + 1); + i = 0; + while (*options) { + if (*options == '"') + break; + if (*options == '\\' && options[1] == '"') { + options += 2; + s[i++] = '"'; + continue; + } + s[i++] = *options++; + } + if (!*options) { + debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + packet_send_debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + continue; + } + s[i] = 0; + packet_send_debug("Adding to environment: %.900s", s); + debug("Adding to environment: %.900s", s); + options++; + new_envstring = xmalloc(sizeof(struct envstring)); + new_envstring->s = s; + new_envstring->next = custom_environment; + custom_environment = new_envstring; + goto next_option; + } + cp = "from=\""; + if (strncmp(options, cp, strlen(cp)) == 0) { + int mname, mip; + char *patterns = xmalloc(strlen(options) + 1); + int i; + options += strlen(cp); + i = 0; + while (*options) { + if (*options == '"') + break; + if (*options == '\\' && options[1] == '"') { + options += 2; + patterns[i++] = '"'; + continue; + } + patterns[i++] = *options++; + } + if (!*options) { + debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + packet_send_debug("%.100s, line %lu: missing end quote", + SSH_USER_PERMITTED_KEYS, linenum); + continue; + } + patterns[i] = 0; + options++; + /* + * Deny access if we get a negative + * match for the hostname or the ip + * or if we get not match at all + */ + mname = match_hostname(get_canonical_hostname(), + patterns, strlen(patterns)); + mip = match_hostname(get_remote_ipaddr(), + patterns, strlen(patterns)); + xfree(patterns); + if (mname == -1 || mip == -1 || + (mname != 1 && mip != 1)) { + log("Authentication tried for %.100s with correct key but not from a permitted host (host=%.200s, ip=%.200s).", + pw->pw_name, get_canonical_hostname(), + get_remote_ipaddr()); + packet_send_debug("Your host '%.200s' is not permitted to use this key for login.", + get_canonical_hostname()); + /* key invalid for this host, reset flags */ + no_agent_forwarding_flag = 0; + no_port_forwarding_flag = 0; + no_pty_flag = 0; + no_x11_forwarding_flag = 0; + while (custom_environment) { + struct envstring *ce = custom_environment; + custom_environment = ce->next; + xfree(ce->s); + xfree(ce); + } + if (forced_command) { + xfree(forced_command); + forced_command = NULL; + } + /* deny access */ + return 0; + } + /* Host name matches. */ + goto next_option; + } +next_option: + /* + * Skip the comma, and move to the next option + * (or break out if there are no more). + */ + if (!*options) + fatal("Bugs in auth-options.c option processing."); + if (*options == ' ' || *options == '\t') + break; /* End of options. */ + if (*options != ',') + goto bad_option; + options++; + /* Process the next option. */ + } + /* grant access */ + return 1; + +bad_option: + log("Bad options in %.100s file, line %lu: %.50s", + SSH_USER_PERMITTED_KEYS, linenum, options); + packet_send_debug("Bad options in %.100s file, line %lu: %.50s", + SSH_USER_PERMITTED_KEYS, linenum, options); + /* deny access */ + return 0; +} -- cgit v1.2.3