diff options
Diffstat (limited to 'sshd.c')
| -rw-r--r-- | sshd.c | 499 |
1 files changed, 286 insertions, 213 deletions
@@ -11,7 +11,7 @@ */ #include "includes.h" -RCSID("$Id: sshd.c,v 1.31 1999/11/24 23:42:08 damien Exp $"); +RCSID("$Id: sshd.c,v 1.32 1999/11/25 00:54:59 damien Exp $"); #include "xmalloc.h" #include "rsa.h" @@ -65,12 +65,16 @@ char *av0; /* Saved arguments to main(). */ char **saved_argv; -/* This is set to the socket that the server is listening; this is used in - the SIGHUP signal handler. */ +/* + * This is set to the socket that the server is listening; this is used in + * the SIGHUP signal handler. + */ int listen_sock; -/* the client's version string, passed by sshd2 in compat mode. - if != NULL, sshd will skip the version-number exchange */ +/* + * the client's version string, passed by sshd2 in compat mode. if != NULL, + * sshd will skip the version-number exchange + */ char *client_version_string = NULL; /* Flags set in auth-rsa from authorized_keys flags. These are set in auth-rsa.c. */ @@ -88,19 +92,23 @@ struct envstring *custom_environment = NULL; /* Session id for the current session. */ unsigned char session_id[16]; -/* Any really sensitive data in the application is contained in this structure. - The idea is that this structure could be locked into memory so that the - pages do not get written into swap. However, there are some problems. - The private key contains BIGNUMs, and we do not (in principle) have - access to the internals of them, and locking just the structure is not - very useful. Currently, memory locking is not implemented. */ +/* + * Any really sensitive data in the application is contained in this + * structure. The idea is that this structure could be locked into memory so + * that the pages do not get written into swap. However, there are some + * problems. The private key contains BIGNUMs, and we do not (in principle) + * have access to the internals of them, and locking just the structure is + * not very useful. Currently, memory locking is not implemented. + */ struct { RSA *private_key; /* Private part of server key. */ RSA *host_key; /* Private part of host key. */ } sensitive_data; -/* Flag indicating whether the current session key has been used. This flag - is set whenever the key is used, and cleared when the key is regenerated. */ +/* + * Flag indicating whether the current session key has been used. This flag + * is set whenever the key is used, and cleared when the key is regenerated. + */ int key_used = 0; /* This is set to true when SIGHUP is received. */ @@ -466,7 +474,7 @@ main(int ac, char **av) fprintf(stderr, "sshd version %s\n", SSH_VERSION); fprintf(stderr, "Usage: %s [options]\n", av0); fprintf(stderr, "Options:\n"); - fprintf(stderr, " -f file Configuration file (default %s/sshd_config)\n", ETCDIR); + fprintf(stderr, " -f file Configuration file (default %s)\n", SERVER_CONFIG_FILE); fprintf(stderr, " -d Debugging mode\n"); fprintf(stderr, " -i Started from inetd\n"); fprintf(stderr, " -q Quiet (no logging)\n"); @@ -614,13 +622,11 @@ main(int ac, char **av) setsockopt(listen_sock, SOL_SOCKET, SO_LINGER, (void *) &linger, sizeof(linger)); - /* Initialize the socket address. */ memset(&sin, 0, sizeof(sin)); sin.sin_family = AF_INET; sin.sin_addr = options.listen_addr; sin.sin_port = htons(options.port); - /* Bind the socket to the desired port. */ if (bind(listen_sock, (struct sockaddr *) & sin, sizeof(sin)) < 0) { error("bind: %.100s", strerror(errno)); shutdown(listen_sock, SHUT_RDWR); @@ -628,12 +634,13 @@ main(int ac, char **av) fatal("Bind to port %d failed.", options.port); } if (!debug_flag) { - /* Record our pid in /etc/sshd_pid to make it - easier to kill the correct sshd. We don\'t - want to do this before the bind above because - the bind will fail if there already is a - daemon, and this will overwrite any old pid in - the file. */ + /* + * Record our pid in /etc/sshd_pid to make it easier + * to kill the correct sshd. We don\'t want to do + * this before the bind above because the bind will + * fail if there already is a daemon, and this will + * overwrite any old pid in the file. + */ f = fopen(SSH_DAEMON_PID_FILE, "w"); if (f) { fprintf(f, "%u\n", (unsigned int) getpid()); @@ -666,8 +673,10 @@ main(int ac, char **av) /* Arrange SIGCHLD to be caught. */ signal(SIGCHLD, main_sigchld_handler); - /* Stay listening for connections until the system crashes - or the daemon is killed with a signal. */ + /* + * Stay listening for connections until the system crashes or + * the daemon is killed with a signal. + */ for (;;) { if (received_sighup) sighup_restart(); @@ -682,12 +691,16 @@ main(int ac, char **av) error("accept: %.100s", strerror(errno)); continue; } - /* Got connection. Fork a child to handle it, - unless we are in debugging mode. */ + /* + * Got connection. Fork a child to handle it, unless + * we are in debugging mode. + */ if (debug_flag) { - /* In debugging mode. Close the listening - socket, and start processing the - connection without forking. */ + /* + * In debugging mode. Close the listening + * socket, and start processing the + * connection without forking. + */ debug("Server will not fork when running in debugging mode."); close(listen_sock); sock_in = newsock; @@ -695,16 +708,17 @@ main(int ac, char **av) pid = getpid(); break; } else { - /* Normal production daemon. Fork, and - have the child process the connection. - The parent continues listening. */ + /* + * Normal production daemon. Fork, and have + * the child process the connection. The + * parent continues listening. + */ if ((pid = fork()) == 0) { - /* Child. Close the listening - socket, and start using the - accepted socket. Reinitialize - logging (since our pid has - changed). We break out of the - loop to handle the connection. */ + /* + * Child. Close the listening socket, and start using the + * accepted socket. Reinitialize logging (since our pid has + * changed). We break out of the loop to handle the connection. + */ close(listen_sock); sock_in = newsock; sock_out = newsock; @@ -731,9 +745,11 @@ main(int ac, char **av) /* This is the child processing a new connection. */ - /* Disable the key regeneration alarm. We will not regenerate the - key since we are no longer in a position to give it to anyone. - We will not restart on SIGHUP since it no longer makes sense. */ + /* + * Disable the key regeneration alarm. We will not regenerate the + * key since we are no longer in a position to give it to anyone. We + * will not restart on SIGHUP since it no longer makes sense. + */ alarm(0); signal(SIGALRM, SIG_DFL); signal(SIGHUP, SIG_DFL); @@ -741,17 +757,20 @@ main(int ac, char **av) signal(SIGQUIT, SIG_DFL); signal(SIGCHLD, SIG_DFL); - /* Set socket options for the connection. We want the socket to - close as fast as possible without waiting for anything. If the - connection is not a socket, these will do nothing. */ - /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on, - sizeof(on)); */ + /* + * Set socket options for the connection. We want the socket to + * close as fast as possible without waiting for anything. If the + * connection is not a socket, these will do nothing. + */ + /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); */ linger.l_onoff = 1; linger.l_linger = 5; setsockopt(sock_in, SOL_SOCKET, SO_LINGER, (void *) &linger, sizeof(linger)); - /* Register our connection. This turns encryption off because we - do not have a key. */ + /* + * Register our connection. This turns encryption off because we do + * not have a key. + */ packet_set_connection(sock_in, sock_out); remote_port = get_remote_port(); @@ -777,12 +796,14 @@ main(int ac, char **av) verbose("Connection from %.500s port %d", remote_ip, remote_port); #endif /* LIBWRAP */ - /* We don\'t want to listen forever unless the other side - successfully authenticates itself. So we set up an alarm which - is cleared after successful authentication. A limit of zero - indicates no limit. Note that we don\'t set the alarm in - debugging mode; it is just annoying to have the server exit - just when you are about to discover the bug. */ + /* + * We don\'t want to listen forever unless the other side + * successfully authenticates itself. So we set up an alarm which is + * cleared after successful authentication. A limit of zero + * indicates no limit. Note that we don\'t set the alarm in debugging + * mode; it is just annoying to have the server exit just when you + * are about to discover the bug. + */ signal(SIGALRM, grace_alarm_handler); if (!debug_flag) alarm(options.login_grace_time); @@ -815,8 +836,10 @@ main(int ac, char **av) buf[sizeof(buf) - 1] = 0; } - /* Check that the versions match. In future this might accept - several versions and set appropriate flags to handle them. */ + /* + * Check that the versions match. In future this might accept + * several versions and set appropriate flags to handle them. + */ if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor, remote_version) != 3) { const char *s = "Protocol mismatch.\n"; @@ -848,11 +871,13 @@ main(int ac, char **av) no_agent_forwarding_flag = 1; } } - /* Check that the connection comes from a privileged port. Rhosts- - and Rhosts-RSA-Authentication only make sense from priviledged - programs. Of course, if the intruder has root access on his - local machine, he can connect from any port. So do not use - these authentication methods from machines that you do not trust. */ + /* + * Check that the connection comes from a privileged port. Rhosts- + * and Rhosts-RSA-Authentication only make sense from priviledged + * programs. Of course, if the intruder has root access on his local + * machine, he can connect from any port. So do not use these + * authentication methods from machines that you do not trust. + */ if (remote_port >= IPPORT_RESERVED || remote_port < IPPORT_RESERVED / 2) { options.rhosts_authentication = 0; @@ -914,13 +939,15 @@ do_connection() int plen, slen; u_int32_t rand = 0; - /* Generate check bytes that the client must send back in the user - packet in order for it to be accepted; this is used to defy ip - spoofing attacks. Note that this only works against somebody - doing IP spoofing from a remote machine; any machine on the - local network can still see outgoing packets and catch the - random cookie. This only affects rhosts authentication, and - this is one of the reasons why it is inherently insecure. */ + /* + * Generate check bytes that the client must send back in the user + * packet in order for it to be accepted; this is used to defy ip + * spoofing attacks. Note that this only works against somebody + * doing IP spoofing from a remote machine; any machine on the local + * network can still see outgoing packets and catch the random + * cookie. This only affects rhosts authentication, and this is one + * of the reasons why it is inherently insecure. + */ for (i = 0; i < 8; i++) { if (i % 4 == 0) rand = arc4random(); @@ -928,9 +955,11 @@ do_connection() rand >>= 8; } - /* Send our public key. We include in the packet 64 bits of - random data that must be matched in the reply in order to - prevent IP spoofing. */ + /* + * Send our public key. We include in the packet 64 bits of random + * data that must be matched in the reply in order to prevent IP + * spoofing. + */ packet_start(SSH_SMSG_PUBLIC_KEY); for (i = 0; i < 8; i++) packet_put_char(check_bytes[i]); @@ -1002,14 +1031,15 @@ do_connection() session_key_int = BN_new(); packet_get_bignum(session_key_int, &slen); - /* Get protocol flags. */ protocol_flags = packet_get_int(); packet_set_protocol_flags(protocol_flags); packet_integrity_check(plen, 1 + 8 + slen + 4, SSH_CMSG_SESSION_KEY); - /* Decrypt it using our private server key and private host key - (key with larger modulus first). */ + /* + * Decrypt it using our private server key and private host key (key + * with larger modulus first). + */ if (BN_cmp(sensitive_data.private_key->n, sensitive_data.host_key->n) > 0) { /* Private key has bigger modulus. */ if (BN_num_bits(sensitive_data.private_key->n) < @@ -1040,14 +1070,15 @@ do_connection() sensitive_data.private_key); } - /* Compute session id for this session. */ compute_session_id(session_id, check_bytes, sensitive_data.host_key->n, sensitive_data.private_key->n); - /* Extract session key from the decrypted integer. The key is in - the least significant 256 bits of the integer; the first byte - of the key is in the highest bits. */ + /* + * Extract session key from the decrypted integer. The key is in the + * least significant 256 bits of the integer; the first byte of the + * key is in the highest bits. + */ BN_mask_bits(session_key_int, sizeof(session_key) * 8); len = BN_num_bytes(session_key_int); if (len < 0 || len > sizeof(session_key)) @@ -1125,8 +1156,7 @@ allowed_user(struct passwd * pw) if (match_pattern(pw->pw_name, options.deny_users[i])) return 0; } - /* Return false if AllowUsers isn't empty and user isn't listed - there */ + /* Return false if AllowUsers isn't empty and user isn't listed there */ if (options.num_allow_users > 0) { if (!pw->pw_name) return 0; @@ -1151,8 +1181,10 @@ allowed_user(struct passwd * pw) if (match_pattern(grp->gr_name, options.deny_groups[i])) return 0; } - /* Return false if AllowGroups isn't empty and user's - group isn't listed there */ + /* + * Return false if AllowGroups isn't empty and user's group + * isn't listed there + */ if (options.num_allow_groups > 0) { if (!grp->gr_name) return 0; @@ -1216,8 +1248,10 @@ do_authentication(char *user) } #endif - /* If we are not running as root, the user must have the same uid - as the server. */ + /* + * If we are not running as root, the user must have the same uid as + * the server. + */ if (getuid() != 0 && pw->pw_uid != getuid()) packet_disconnect("Cannot change user when server not running as root."); @@ -1357,10 +1391,12 @@ do_authloop(struct passwd * pw) verbose("Rhosts authentication disabled."); break; } - /* Get client user name. Note that we just have - to trust the client; this is one reason why - rhosts authentication is insecure. (Another is - IP-spoofing on a local network.) */ + /* + * Get client user name. Note that we just have to + * trust the client; this is one reason why rhosts + * authentication is insecure. (Another is + * IP-spoofing on a local network.) + */ client_user = packet_get_string(&ulen); packet_integrity_check(plen, 4 + ulen, type); @@ -1379,9 +1415,11 @@ do_authloop(struct passwd * pw) verbose("Rhosts with RSA authentication disabled."); break; } - /* Get client user name. Note that we just have - to trust the client; root on the client machine - can claim to be any user. */ + /* + * Get client user name. Note that we just have to + * trust the client; root on the client machine can + * claim to be any user. + */ client_user = packet_get_string(&ulen); /* Get the client host key. */ @@ -1425,9 +1463,11 @@ do_authloop(struct passwd * pw) verbose("Password authentication disabled."); break; } - /* Read user password. It is in plain text, but - was transmitted over the encrypted channel so - it is not visible to an outside observer. */ + /* + * Read user password. It is in plain text, but was + * transmitted over the encrypted channel so it is + * not visible to an outside observer. + */ password = packet_get_string(&dlen); packet_integrity_check(plen, 4 + dlen, type); @@ -1463,8 +1503,7 @@ do_authloop(struct passwd * pw) skeyinfo = skey_fake_keyinfo(pw->pw_name); } if (skeyinfo != NULL) { - /* we send our s/key- in - tis-challenge messages */ + /* we send our s/key- in tis-challenge messages */ debug("sending challenge '%s'", skeyinfo); packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE); packet_put_string(skeyinfo, strlen(skeyinfo)); @@ -1493,8 +1532,10 @@ do_authloop(struct passwd * pw) #endif default: - /* Any unknown messages will be ignored (and - failure returned) during authentication. */ + /* + * Any unknown messages will be ignored (and failure + * returned) during authentication. + */ log("Unknown message during authentication: type %d", type); break; } @@ -1559,11 +1600,12 @@ do_fake_authloop(char *user) packet_send(); packet_write_wait(); - /* Keep reading packets, and always respond with a failure. This - is to avoid disclosing whether such a user really exists. */ + /* + * Keep reading packets, and always respond with a failure. This is + * to avoid disclosing whether such a user really exists. + */ for (attempt = 1;; attempt++) { - /* Read a packet. This will not return if the client - disconnects. */ + /* Read a packet. This will not return if the client disconnects. */ int plen; int type = packet_read(&plen); #ifdef SKEY @@ -1583,8 +1625,10 @@ do_fake_authloop(char *user) if (attempt > AUTH_FAIL_MAX) packet_disconnect(AUTH_FAIL_MSG, user); - /* Send failure. This should be indistinguishable from a - failed authentication. */ + /* + * Send failure. This should be indistinguishable from a + * failed authentication. + */ packet_start(SSH_SMSG_FAILURE); packet_send(); packet_write_wait(); @@ -1630,19 +1674,25 @@ do_authenticated(struct passwd * pw) mode_t tty_mode; int n_bytes; - /* Cancel the alarm we set to limit the time taken for - authentication. */ + /* + * Cancel the alarm we set to limit the time taken for + * authentication. + */ alarm(0); - /* Inform the channel mechanism that we are the server side and - that the client may request to connect to any port at all. - (The user could do it anyway, and we wouldn\'t know what is - permitted except by the client telling us, so we can equally - well trust the client not to request anything bogus.) */ + /* + * Inform the channel mechanism that we are the server side and that + * the client may request to connect to any port at all. (The user + * could do it anyway, and we wouldn\'t know what is permitted except + * by the client telling us, so we can equally well trust the client + * not to request anything bogus.) + */ channel_permit_all_opens(); - /* We stay in this loop until the client requests to execute a - shell or a command. */ + /* + * We stay in this loop until the client requests to execute a shell + * or a command. + */ while (1) { int plen, dlen; @@ -1826,8 +1876,10 @@ do_authenticated(struct passwd * pw) return; default: - /* Any unknown messages in this phase are ignored, - and a failure message is returned. */ + /* + * Any unknown messages in this phase are ignored, + * and a failure message is returned. + */ log("Unknown packet type received after authentication: %d", type); goto fail; } @@ -1852,8 +1904,10 @@ fail: continue; do_forced_command: - /* There is a forced command specified for this login. - Execute it. */ + /* + * There is a forced command specified for this login. + * Execute it. + */ debug("Executing forced command: %.900s", forced_command); if (have_pty) do_exec_pty(forced_command, ptyfd, ttyfd, ttyname, pw, term, display, proto, data); @@ -1897,14 +1951,18 @@ do_exec_no_pty(const char *command, struct passwd * pw, /* Child. Reinitialize the log since the pid has changed. */ log_init(av0, options.log_level, options.log_facility, log_stderr); - /* Create a new session and process group since the 4.4BSD - setlogin() affects the entire process group. */ + /* + * Create a new session and process group since the 4.4BSD + * setlogin() affects the entire process group. + */ if (setsid() < 0) error("setsid failed: %.100s", strerror(errno)); #ifdef USE_PIPES - /* Redirect stdin. We close the parent side of the socket - pair, and make the child side the standard input. */ + /* + * Redirect stdin. We close the parent side of the socket + * pair, and make the child side the standard input. + */ close(pin[1]); if (dup2(pin[0], 0) < 0) perror("dup2 stdin"); @@ -1922,9 +1980,11 @@ do_exec_no_pty(const char *command, struct passwd * pw, perror("dup2 stderr"); close(perr[1]); #else /* USE_PIPES */ - /* Redirect stdin, stdout, and stderr. Stdin and stdout - will use the same socket, as some programs - (particularly rdist) seem to depend on it. */ + /* + * Redirect stdin, stdout, and stderr. Stdin and stdout will + * use the same socket, as some programs (particularly rdist) + * seem to depend on it. + */ close(inout[1]); close(err[1]); if (dup2(inout[0], 0) < 0) /* stdin */ @@ -1955,8 +2015,10 @@ do_exec_no_pty(const char *command, struct passwd * pw, close(inout[0]); close(err[0]); - /* Enter the interactive session. Note: server_loop must be able - to handle the case that fdin and fdout are the same. */ + /* + * Enter the interactive session. Note: server_loop must be able to + * handle the case that fdin and fdout are the same. + */ server_loop(pid, inout[1], inout[1], err[1]); /* server_loop has closed inout[1] and err[1]. */ #endif /* USE_PIPES */ @@ -2012,8 +2074,10 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, /* Get remote host name. */ hostname = get_canonical_hostname(); - /* Get the time when the user last logged in. Buf will be set to - contain the hostname the last login was from. */ + /* + * Get the time when the user last logged in. Buf will be set to + * contain the hostname the last login was from. + */ if (!options.use_login) { last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name, buf, sizeof(buf)); @@ -2049,9 +2113,11 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, /* Close the extra descriptor for the pseudo tty. */ close(ttyfd); - /* Get IP address of client. This is needed because we - want to record where the user logged in from. If the - connection is not a socket, let the ip address be 0.0.0.0. */ + /* + * Get IP address of client. This is needed because we want + * to record where the user logged in from. If the + * connection is not a socket, let the ip address be 0.0.0.0. + */ memset(&from, 0, sizeof(from)); if (packet_get_connection_in() == packet_get_connection_out()) { fromlen = sizeof(from); @@ -2075,12 +2141,14 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, fprintf(stderr, pamconv_msg); #endif - /* If the user has logged in before, display the time of - last login. However, don't display anything extra if a - command has been specified (so that ssh can be used to - execute commands on a remote machine without users - knowing they are going to another machine). Login(1) - will do this for us as well, so check if login(1) is used */ + /* + * If the user has logged in before, display the time of last + * login. However, don't display anything extra if a command + * has been specified (so that ssh can be used to execute + * commands on a remote machine without users knowing they + * are going to another machine). Login(1) will do this for + * us as well, so check if login(1) is used + */ if (command == NULL && last_login_time != 0 && !quiet_login && !options.use_login) { /* Convert the date to a string. */ @@ -2095,10 +2163,12 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, else printf("Last login: %s from %s\r\n", time_string, buf); } - /* Print /etc/motd unless a command was specified or - printing it was disabled in server options or login(1) - will be used. Note that some machines appear to print - it in /etc/profile or similar. */ + /* + * Print /etc/motd unless a command was specified or printing + * it was disabled in server options or login(1) will be + * used. Note that some machines appear to print it in + * /etc/profile or similar. + */ if (command == NULL && options.print_motd && !quiet_login && !options.use_login) { /* Print /etc/motd if it exists. */ @@ -2118,15 +2188,19 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, /* Parent. Close the slave side of the pseudo tty. */ close(ttyfd); - /* Create another descriptor of the pty master side for use as the - standard input. We could use the original descriptor, but this - simplifies code in server_loop. The descriptor is bidirectional. */ + /* + * Create another descriptor of the pty master side for use as the + * standard input. We could use the original descriptor, but this + * simplifies code in server_loop. The descriptor is bidirectional. + */ fdout = dup(ptyfd); if (fdout < 0) packet_disconnect("dup failed: %.100s", strerror(errno)); - /* Add a cleanup function to clear the utmp entry and record logout - time in case we call fatal() (e.g., the connection gets closed). */ + /* + * Add a cleanup function to clear the utmp entry and record logout + * time in case we call fatal() (e.g., the connection gets closed). + */ cleanup_context.pid = pid; cleanup_context.ttyname = ttyname; fatal_add_cleanup(pty_cleanup_proc, (void *) &cleanup_context); @@ -2144,9 +2218,11 @@ do_exec_pty(const char *command, int ptyfd, int ttyfd, /* Release the pseudo-tty. */ pty_release(ttyname); - /* Close the server side of the socket pairs. We must do this - after the pty cleanup, so that another process doesn't get this - pty while we're still cleaning up. */ + /* + * Close the server side of the socket pairs. We must do this after + * the pty cleanup, so that another process doesn't get this pty + * while we're still cleaning up. + */ close(ptyfd); close(fdout); } @@ -2162,19 +2238,21 @@ child_set_env(char ***envp, unsigned int *envsizep, const char *name, unsigned int i, namelen; char **env; - /* Find the slot where the value should be stored. If the - variable already exists, we reuse the slot; otherwise we append - a new slot at the end of the array, expanding if necessary. */ + /* + * Find the slot where the value should be stored. If the variable + * already exists, we reuse the slot; otherwise we append a new slot + * at the end of the array, expanding if necessary. + */ env = *envp; namelen = strlen(name); for (i = 0; env[i]; i++) if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') break; if (env[i]) { - /* Name already exists. Reuse the slot. */ + /* Reuse the slot. */ xfree(env[i]); } else { - /* New variable. Expand the array if necessary. */ + /* New variable. Expand if necessary. */ if (i >= (*envsizep) - 1) { (*envsizep) += 50; env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *)); @@ -2202,40 +2280,27 @@ read_environment_file(char ***env, unsigned int *envsize, char buf[4096]; char *cp, *value; - /* Open the environment file. */ f = fopen(filename, "r"); if (!f) return; - /* Process each line. */ while (fgets(buf, sizeof(buf), f)) { - /* Skip leading whitespace. */ - for (cp = buf; *cp == ' ' || *cp == '\t'; cp++); - - /* Ignore empty and comment lines. */ + for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) + ; if (!*cp || *cp == '#' || *cp == '\n') continue; - - /* Remove newline. */ if (strchr(cp, '\n')) *strchr(cp, '\n') = '\0'; - - /* Find the equals sign. Its lack indicates badly - formatted line. */ value = strchr(cp, '='); if (value == NULL) { fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf); continue; } - /* Replace the equals sign by nul, and advance value to - the value string. */ + /* Replace the equals sign by nul, and advance value to the value string. */ *value = '\0'; value++; - - /* Set the value in environment. */ child_set_env(env, envsize, cp, value); } - fclose(f); } @@ -2299,8 +2364,10 @@ do_child(const char *command, struct passwd * pw, const char *term, if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid) fatal("Failed to set uids to %d.", (int) pw->pw_uid); } - /* Get the shell from the password data. An empty shell field is - legal, and means /bin/sh. */ + /* + * Get the shell from the password data. An empty shell field is + * legal, and means /bin/sh. + */ shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell; #ifdef AFS @@ -2315,8 +2382,7 @@ do_child(const char *command, struct passwd * pw, const char *term, } #endif /* AFS */ - /* Initialize the environment. In the first part we allocate - space for all environment variables. */ + /* Initialize the environment. */ envsize = 100; env = xmalloc(envsize * sizeof(char *)); env[0] = NULL; @@ -2335,7 +2401,6 @@ do_child(const char *command, struct passwd * pw, const char *term, /* Normal systems set SHELL by default. */ child_set_env(&env, &envsize, "SHELL", shell); } - /* Let it inherit timezone if we have one. */ if (getenv("TZ")) child_set_env(&env, &envsize, "TZ", getenv("TZ")); @@ -2354,20 +2419,14 @@ do_child(const char *command, struct passwd * pw, const char *term, xfree(ce); } - /* Set SSH_CLIENT. */ snprintf(buf, sizeof buf, "%.50s %d %d", get_remote_ipaddr(), get_remote_port(), options.port); child_set_env(&env, &envsize, "SSH_CLIENT", buf); - /* Set SSH_TTY if we have a pty. */ if (ttyname) child_set_env(&env, &envsize, "SSH_TTY", ttyname); - - /* Set TERM if we have a pty. */ if (term) child_set_env(&env, &envsize, "TERM", term); - - /* Set DISPLAY if we have one. */ if (display) child_set_env(&env, &envsize, "DISPLAY", display); @@ -2400,52 +2459,57 @@ do_child(const char *command, struct passwd * pw, const char *term, } #endif /* HAVE_LIBPAM */ - /* Set XAUTHORITY to always be a local file. */ if (xauthfile) child_set_env(&env, &envsize, "XAUTHORITY", xauthfile); - /* Set variable for forwarded authentication connection, if we - have one. */ if (auth_get_socket_name() != NULL) child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME, auth_get_socket_name()); - /* Read $HOME/.ssh/environment. */ + /* read $HOME/.ssh/environment. */ if (!options.use_login) { snprintf(buf, sizeof buf, "%.200s/.ssh/environment", pw->pw_dir); read_environment_file(&env, &envsize, buf); } - /* If debugging, dump the environment to stderr. */ if (debug_flag) { + /* dump the environment */ fprintf(stderr, "Environment:\n"); for (i = 0; env[i]; i++) fprintf(stderr, " %.200s\n", env[i]); } - /* Close the connection descriptors; note that this is the child, - and the server will still have the socket open, and it is - important that we do not shutdown it. Note that the - descriptors cannot be closed before building the environment, - as we call get_remote_ipaddr there. */ + /* + * Close the connection descriptors; note that this is the child, and + * the server will still have the socket open, and it is important + * that we do not shutdown it. Note that the descriptors cannot be + * closed before building the environment, as we call + * get_remote_ipaddr there. + */ if (packet_get_connection_in() == packet_get_connection_out()) close(packet_get_connection_in()); else { close(packet_get_connection_in()); close(packet_get_connection_out()); } - /* Close all descriptors related to channels. They will still - remain open in the parent. */ + /* + * Close all descriptors related to channels. They will still remain + * open in the parent. + */ + /* XXX better use close-on-exec? -markus */ channel_close_all(); - /* Close any extra file descriptors. Note that there may still be - descriptors left by system functions. They will be closed - later. */ + /* + * Close any extra file descriptors. Note that there may still be + * descriptors left by system functions. They will be closed later. + */ endpwent(); endhostent(); - /* Close any extra open file descriptors so that we don\'t have - them hanging around in clients. Note that we want to do this - after initgroups, because at least on Solaris 2.3 it leaves - file descriptors open. */ + /* + * Close any extra open file descriptors so that we don\'t have them + * hanging around in clients. Note that we want to do this after + * initgroups, because at least on Solaris 2.3 it leaves file + * descriptors open. + */ for (i = 3; i < 64; i++) close(i); @@ -2454,12 +2518,16 @@ do_child(const char *command, struct passwd * pw, const char *term, fprintf(stderr, "Could not chdir to home directory %s: %s\n", pw->pw_dir, strerror(errno)); - /* Must take new environment into use so that .ssh/rc, /etc/sshrc - and xauth are run in the proper environment. */ + /* + * Must take new environment into use so that .ssh/rc, /etc/sshrc and + * xauth are run in the proper environment. + */ environ = env; - /* Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found - first in this order). */ + /* + * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first + * in this order). + */ if (!options.use_login) { if (stat(SSH_USER_RC, &st) >= 0) { if (debug_flag) @@ -2486,8 +2554,7 @@ do_child(const char *command, struct passwd * pw, const char *term, } #ifdef XAUTH_PATH else { - /* Add authority data to .Xauthority if - appropriate. */ + /* Add authority data to .Xauthority if appropriate. */ if (auth_proto != NULL && auth_data != NULL) { if (debug_flag) fprintf(stderr, "Running %.100s add %.100s %.100s %.100s\n", @@ -2510,15 +2577,19 @@ do_child(const char *command, struct passwd * pw, const char *term, else cp = shell; } - /* If we have no command, execute the shell. In this case, the - shell name to be passed in argv[0] is preceded by '-' to - indicate that this is a login shell. */ + /* + * If we have no command, execute the shell. In this case, the shell + * name to be passed in argv[0] is preceded by '-' to indicate that + * this is a login shell. + */ if (!command) { if (!options.use_login) { char buf[256]; - /* Check for mail if we have a tty and it was - enabled in server options. */ + /* + * Check for mail if we have a tty and it was enabled + * in server options. + */ if (ttyname && options.check_mail) { char *mailbox; struct stat mailstat; @@ -2558,8 +2629,10 @@ do_child(const char *command, struct passwd * pw, const char *term, exit(1); } } - /* Execute the command using the user's shell. This uses the -c - option to execute the command. */ + /* + * Execute the command using the user's shell. This uses the -c + * option to execute the command. + */ argv[0] = (char *) cp; argv[1] = "-c"; argv[2] = (char *) command; |