git ssb

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#define _GNU_SOURCE
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#include <sys/types.h>
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#include <fcntl.h>
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#include <errno.h>
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#include <string.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <signal.h>
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#include <sys/socket.h>
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#include <sys/wait.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <netdb.h>
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#include <pwd.h>
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#include <syslog.h>
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#include <libgen.h>
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#include <time.h>
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#include <getopt.h>
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#ifndef VERSION
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#define VERSION "v?"
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#endif
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#define CHECK_RES_DIE(res, str) \
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    if (res == -1) {    \
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       perror(str);     \
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       exit(1);         \
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    }
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#define CHECK_RES_RETURN(res, str) \
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    if (res == -1) {                                    \
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        log_message(LOG_CRIT, "%s: %d\n", str, errno);  \
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        return res;                                     \
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    } 
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#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
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#if 1
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#define TRACE fprintf(stderr, "%s:%d\n", __FILE__, __LINE__);
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#else
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#define TRACE
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#endif
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enum connection_state {
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    ST_PROBING=1,    /* Waiting for timeout to find where to forward */
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    ST_SHOVELING   /* Connexion is established */
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};
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typedef int T_PROTO_ID; /* Index into protocols[] array */
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/* For each protocol we need: */
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struct proto {
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    int affected;       /* are we actually using it? */
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    char* description;  /* a string that says what it is (for logging and command-line parsing) */
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    char* service;      /* service name to do libwrap checks */
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    struct addrinfo saddr; /* where to switch that protocol */
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    int (*probe)(const char*, int); /* function to probe that protocol */
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};
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/* A table in common.c contains all the known protocols */
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extern struct proto protocols[];
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extern int num_known_protocols;
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/* this is used to pass protocols through the command-line parameter parsing */
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#define PROT_SHIFT 1000  /* protocol options will be 1000, 1001, etc */
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/* A 'queue' is composed of a file descriptor (which can be read from or
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 * written to), and a queue for defered write data */
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struct queue {
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    int fd;
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    void *begin_defered_data;
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    void *defered_data;
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    int defered_data_size;
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};
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struct connection {
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    enum connection_state state;
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    time_t probe_timeout;
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    /* q[0]: queue for external connection (client);
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     * q[1]: queue for internal connection (httpd or sshd);
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     * */
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    struct queue q[2];
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};
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#define FD_CNXCLOSED    0
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#define FD_NODATA       -1
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#define FD_STALLED      -2
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/* common.c */
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void init_cnx(struct connection *cnx);
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int connect_addr(struct addrinfo *addr, char* cnx_name);
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int fd2fd(struct queue *target, struct queue *from);
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char* sprintaddr(char* buf, size_t size, struct addrinfo *a);
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void resolve_name(struct addrinfo **out, char* fullname);
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T_PROTO_ID probe_client_protocol(struct connection *cnx);
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void log_connection(struct connection *cnx);
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int check_access_rights(int in_socket, char* service);
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void setup_signals(void);
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void setup_syslog(char* bin_name);
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void drop_privileges(char* user_name);
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void write_pid_file(char* pidfile);
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void printsettings(void);
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void parse_cmdline(int argc, char* argv[]);
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void log_message(int type, char* msg, ...);
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void dump_connection(struct connection *cnx);
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void append_protocols(struct option *options, int n_opts, struct proto *prot, int n_prots);
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int start_listen_sockets(int *sockfd[], struct addrinfo *addr_list);
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int defer_write(struct queue *q, void* data, int data_size);
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int flush_defered(struct queue *q);
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extern int probing_timeout, verbose, inetd, foreground, numeric;
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extern struct sockaddr_storage addr_ssl, addr_ssh, addr_openvpn;
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extern struct addrinfo *addr_listen;
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extern const char* USAGE_STRING;
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extern char* user_name, *pid_file;
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extern const char* server_type;
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/* sslh-fork.c */
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void start_shoveler(int);
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void main_loop(int *listen_sockets, int num_addr_listen);
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