diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/clamsmtpd.c | 489 |
1 files changed, 290 insertions, 199 deletions
diff --git a/src/clamsmtpd.c b/src/clamsmtpd.c index 5cc9c7f..ef4b4b3 100644 --- a/src/clamsmtpd.c +++ b/src/clamsmtpd.c @@ -58,7 +58,7 @@ #include "util.h" /* ----------------------------------------------------------------------- - * Structures + * STRUCTURES */ typedef struct clamsmtp_thread @@ -72,7 +72,7 @@ clamsmtp_thread_t; #define RETURN(x) { ret = x; goto cleanup; } /* ----------------------------------------------------------------------- - * Strings + * STRINGS */ #define KL(s) ((sizeof(s) - 1) / sizeof(char)) @@ -117,17 +117,18 @@ clamsmtp_thread_t; #define CLAM_DISCONNECT "END\n" /* ----------------------------------------------------------------------- - * Default Settings + * DEFAULT SETTINGS */ #define DEFAULT_SOCKET "10025" +#define DEFAULT_PORT 10025 #define DEFAULT_CLAMAV "/var/run/clamav/clamd" #define DEFAULT_MAXTHREADS 64 #define DEFAULT_TIMEOUT 180 #define DEFAULT_HEADER "X-AV-Checked: ClamAV using ClamSMTP\r\n" /* ----------------------------------------------------------------------- - * Globals + * GLOBALS */ int g_daemonized = 0; /* Currently running as a daemon */ @@ -155,7 +156,7 @@ pthread_mutexattr_t g_mutexattr; /* ----------------------------------------------------------------------- - * Forward Declarations + * FORWARD DECLARATIONS */ static usage(); @@ -174,12 +175,17 @@ static int transfer_to_file(clamsmtp_context_t* ctx, char* tempname); static int transfer_from_file(clamsmtp_context_t* ctx, const char* filename); static int clam_scan_file(clamsmtp_context_t* ctx, const char* tempname, char* logline); static int read_server_response(clamsmtp_context_t* ctx); +static int connect_socket(clamsmtp_context_t* ctx, struct sockaddr_any* sany, const char* addrname); static void read_junk(clamsmtp_context_t* ctx, int fd); static int read_line(clamsmtp_context_t* ctx, int* fd, int trim); static int write_data(clamsmtp_context_t* ctx, int* fd, unsigned char* buf); static int write_data_raw(clamsmtp_context_t* ctx, int* fd, unsigned char* buf, int len); +/* ---------------------------------------------------------------------------------- + * STARTUP ETC... + */ + int main(int argc, char* argv[]) { const char* listensock = DEFAULT_SOCKET; @@ -277,7 +283,7 @@ int main(int argc, char* argv[]) messagex(NULL, LOG_DEBUG, "starting up..."); /* Parse all the addresses */ - if(sock_any_pton(listensock, &addr, SANY_OPT_DEFANY) == -1) + if(sock_any_pton(listensock, &addr, SANY_OPT_DEFANY | SANY_OPT_DEFPORT(DEFAULT_PORT)) == -1) errx(1, "invalid listen socket name or ip: %s", listensock); if(sock_any_pton(g_outname, &g_outaddr, SANY_OPT_DEFPORT(25)) == -1) errx(1, "invalid connect socket name or ip: %s", g_outname); @@ -344,6 +350,54 @@ int main(int argc, char* argv[]) return 0; } +static void on_quit(int signal) +{ + g_quit = 1; + + /* fprintf(stderr, "clamsmtpd: got signal to quit\n"); */ +} + +static int usage() +{ + fprintf(stderr, "clamsmtpd [-bq] [-c clamaddr] [-d debuglevel] [-D tmpdir] [-h header] " + "[-l listenaddr] [-m maxconn] [-p pidfile] [-t timeout] serveraddr\n"); + exit(2); +} + +static void pid_file(const char* pidfile, int write) +{ + if(write) + { + FILE* f = fopen(pidfile, "w"); + if(f == NULL) + { + message(NULL, LOG_ERR, "couldn't open pid file: %s", pidfile); + } + else + { + fprintf(f, "%d\n", (int)getpid()); + + if(ferror(f)) + message(NULL, LOG_ERR, "couldn't write to pid file: %s", pidfile); + + fclose(f); + } + + messagex(NULL, LOG_DEBUG, "wrote pid file: %s", pidfile); + } + + else + { + unlink(pidfile); + messagex(NULL, LOG_DEBUG, "removed pid file: %s", pidfile); + } +} + + +/* ---------------------------------------------------------------------------------- + * CONNECTION HANDLING + */ + static void connection_loop(int sock) { clamsmtp_thread_t* threads = NULL; @@ -389,6 +443,11 @@ static void connection_loop(int sock) continue; } + /* Set timeouts on client */ + if(setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &g_timeout, sizeof(g_timeout)) < 0 || + setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &g_timeout, sizeof(g_timeout)) < 0) + message(NULL, LOG_WARNING, "couldn't set timeouts on incoming connection"); + /* Look for thread and also clean up others */ for(i = 0; i < g_maxthreads; i++) { @@ -458,49 +517,6 @@ static void connection_loop(int sock) pthread_mutexattr_destroy(&g_mutexattr); } -static void on_quit(int signal) -{ - g_quit = 1; - - /* fprintf(stderr, "clamsmtpd: got signal to quit\n"); */ -} - -static int usage() -{ - fprintf(stderr, "clamsmtpd [-bq] [-c clamaddr] [-d debuglevel] [-D tmpdir] [-h header] " - "[-l listenaddr] [-m maxconn] [-p pidfile] [-t timeout] serveraddr\n"); - exit(2); -} - -static void pid_file(const char* pidfile, int write) -{ - if(write) - { - FILE* f = fopen(pidfile, "w"); - if(f == NULL) - { - message(NULL, LOG_ERR, "couldn't open pid file: %s", pidfile); - } - else - { - fprintf(f, "%d\n", (int)getpid()); - - if(ferror(f)) - message(NULL, LOG_ERR, "couldn't write to pid file: %s", pidfile); - - fclose(f); - } - - messagex(NULL, LOG_DEBUG, "wrote pid file: %s", pidfile); - } - - else - { - unlink(pidfile); - messagex(NULL, LOG_DEBUG, "removed pid file: %s", pidfile); - } -} - static void* thread_main(void* arg) { clamsmtp_thread_t* thread = (clamsmtp_thread_t*)arg; @@ -509,6 +525,7 @@ static void* thread_main(void* arg) const char* outname; char buf[MAXPATHLEN]; clamsmtp_context_t ctx; + int processing = 0; int ret = 0; ASSERT(thread); @@ -561,21 +578,16 @@ static void* thread_main(void* arg) /* Connect to the server */ - if((ctx.server = socket(SANY_TYPE(*outaddr), SOCK_STREAM, 0)) < 0 || - connect(ctx.server, &SANY_ADDR(*outaddr), SANY_LEN(*outaddr)) < 0) - { - message(&ctx, LOG_ERR, "couldn't connect to %s", outname); + if((ctx.server = connect_socket(&ctx, outaddr, outname)) == -1) RETURN(-1); - } - - messagex(&ctx, LOG_DEBUG, "connected to server: %s", outname); - + /* ... and to the AV daemon */ if(connect_clam(&ctx) == -1) RETURN(-1); /* call the processor */ + processing = 1; ret = smtp_passthru(&ctx); cleanup: @@ -583,7 +595,7 @@ cleanup: disconnect_clam(&ctx); /* Let the client know about fatal errors */ - if(ret == -1 && ctx.client != -1) + if(!processing && ret == -1 && ctx.client != -1) write_data(&ctx, &(ctx.client), SMTP_STARTFAILED); if(ctx.client != -1) @@ -606,12 +618,18 @@ cleanup: return (void*)(ret == 0 ? 0 : 1); } + +/* ---------------------------------------------------------------------------------- + * SMTP HANDLING + */ + static int smtp_passthru(clamsmtp_context_t* ctx) { char logline[LINE_LENGTH]; int r, ret = 0; int first_rsp = 1; fd_set mask; + int neterror = 0; ASSERT(ctx->clam != -1 && ctx->server != -1); logline[0] = 0; @@ -627,9 +645,11 @@ static int smtp_passthru(clamsmtp_context_t* ctx) { case 0: messagex(ctx, LOG_ERR, "network operation timed out"); + neterror = 1; RETURN(-1); case -1: message(ctx, LOG_ERR, "couldn't select on sockets"); + neterror = 1; RETURN(-1); }; @@ -764,7 +784,7 @@ static int smtp_passthru(clamsmtp_context_t* ctx) cleanup: - if(ret == -1 && ctx->client != -1) + if(!neterror && ret == -1 && ctx->client != -1) write_data(ctx, &(ctx->client), SMTP_FAILED); return ret; @@ -798,120 +818,6 @@ static void add_to_logline(char* logline, char* prefix, char* line) *(--t) = 0; } -static int connect_clam(clamsmtp_context_t* ctx) -{ - int r, len = -1; - int ret = 0; - - ASSERT(ctx); - ASSERT(ctx->clam == -1); - - if((ctx->clam = socket(SANY_TYPE(g_clamaddr), SOCK_STREAM, 0)) < 0 || - connect(ctx->clam, &SANY_ADDR(g_clamaddr), SANY_LEN(g_clamaddr)) < 0) - { - message(ctx, LOG_ERR, "couldn't connect to clamd at %s", g_clamname); - RETURN(-1); - } - - read_junk(ctx, ctx->clam); - - /* Send a session and a check header to ClamAV */ - - if(write_data(ctx, &(ctx->clam), "SESSION\n") == -1) - RETURN(-1); - - read_junk(ctx, ctx->clam); -/* - if(write_data(ctx, &(ctx->clam), "PING\n") == -1 || - read_line(ctx, &(ctx->clam), 1) == -1) - RETURN(-1); - - if(strcmp(ctx->line, CONNECT_RESPONSE) != 0) - { - message(ctx, LOG_ERR, "clamd sent an unexpected response: %s", ctx->line); - RETURN(-1); - } -*/ - messagex(ctx, LOG_DEBUG, "connected to clamd: %s", g_clamname); - -cleanup: - - if(ret < 0) - { - if(ctx->clam != -1) - { - shutdown(ctx->clam, SHUT_RDWR); - ctx->clam = -1; - } - } - - return ret; -} - -static int disconnect_clam(clamsmtp_context_t* ctx) -{ - if(ctx->clam == -1) - return 0; - - if(write_data(ctx, &(ctx->clam), CLAM_DISCONNECT) != -1) - read_junk(ctx, ctx->clam); - - shutdown(ctx->clam, SHUT_RDWR); - messagex(ctx, LOG_DEBUG, "disconnected from clamd"); - ctx->clam = -1; - return 0; -} - -static int clam_scan_file(clamsmtp_context_t* ctx, const char* tempname, char* logline) -{ - int len; - - ASSERT(LINE_LENGTH > MAXPATHLEN + 32); - - strcpy(ctx->line, CLAM_SCAN); - strcat(ctx->line, tempname); - strcat(ctx->line, "\n"); - - if(write_data(ctx, &(ctx->clam), ctx->line) == -1) - return -1; - - len = read_line(ctx, &(ctx->clam), 1); - if(len == 0) - { - messagex(ctx, LOG_ERR, "clamd disconnected unexpectedly"); - return -1; - } - - if(is_last_word(ctx->line, CLAM_OK, KL(CLAM_OK))) - { - add_to_logline(logline, "status=", "CLEAN"); - messagex(ctx, LOG_DEBUG, "no virus"); - return 0; - } - - if(is_last_word(ctx->line, CLAM_FOUND, KL(CLAM_FOUND))) - { - len = strlen(tempname); - - if(ctx->linelen > len) - add_to_logline(logline, "status=VIRUS:", ctx->line + len + 1); - else - add_to_logline(logline, "status=", "VIRUS"); - - messagex(ctx, LOG_DEBUG, "found virus"); - return 1; - } - - if(is_last_word(ctx->line, CLAM_ERROR, KL(CLAM_ERROR))) - { - messagex(ctx, LOG_ERR, "clamav error: %s", ctx->line); - return -1; - } - - messagex(ctx, LOG_ERR, "unexepected response from clamd: %s", ctx->line); - return -1; -} - static int avcheck_data(clamsmtp_context_t* ctx, char* logline) { /* @@ -1028,6 +934,147 @@ static int complete_data_transfer(clamsmtp_context_t* ctx, const char* tempname) return 0; } +static int read_server_response(clamsmtp_context_t* ctx) +{ + /* Read response line from the server */ + if(read_line(ctx, &(ctx->server), 0) == -1) + return -1; + + if(ctx->linelen == 0) + { + messagex(ctx, LOG_ERR, "server disconnected unexpectedly"); + + /* Tell the client it went wrong */ + write_data(ctx, &(ctx->client), SMTP_FAILED); + return 0; + } + + if(LINE_TOO_LONG(ctx)) + messagex(ctx, LOG_WARNING, "SMTP response line too long. discarded extra"); + + return 0; +} + + +/* ---------------------------------------------------------------------------------- + * CLAM AV + */ + +static int connect_clam(clamsmtp_context_t* ctx) +{ + int r, len = -1; + int ret = 0; + + ASSERT(ctx); + ASSERT(ctx->clam == -1); + + if((ctx->clam = connect_socket(ctx, &g_clamaddr, g_clamname)) == -1) + RETURN(-1); + + read_junk(ctx, ctx->clam); + + /* Send a session and a check header to ClamAV */ + + if(write_data(ctx, &(ctx->clam), "SESSION\n") == -1) + RETURN(-1); + + read_junk(ctx, ctx->clam); +/* + if(write_data(ctx, &(ctx->clam), "PING\n") == -1 || + read_line(ctx, &(ctx->clam), 1) == -1) + RETURN(-1); + + if(strcmp(ctx->line, CONNECT_RESPONSE) != 0) + { + message(ctx, LOG_ERR, "clamd sent an unexpected response: %s", ctx->line); + RETURN(-1); + } +*/ + messagex(ctx, LOG_DEBUG, "connected to clamd: %s", g_clamname); + +cleanup: + + if(ret < 0) + { + if(ctx->clam != -1) + { + shutdown(ctx->clam, SHUT_RDWR); + ctx->clam = -1; + } + } + + return ret; +} + +static int disconnect_clam(clamsmtp_context_t* ctx) +{ + if(ctx->clam == -1) + return 0; + + if(write_data(ctx, &(ctx->clam), CLAM_DISCONNECT) != -1) + read_junk(ctx, ctx->clam); + + shutdown(ctx->clam, SHUT_RDWR); + messagex(ctx, LOG_DEBUG, "disconnected from clamd"); + ctx->clam = -1; + return 0; +} + +static int clam_scan_file(clamsmtp_context_t* ctx, const char* tempname, char* logline) +{ + int len; + + ASSERT(LINE_LENGTH > MAXPATHLEN + 32); + + strcpy(ctx->line, CLAM_SCAN); + strcat(ctx->line, tempname); + strcat(ctx->line, "\n"); + + if(write_data(ctx, &(ctx->clam), ctx->line) == -1) + return -1; + + len = read_line(ctx, &(ctx->clam), 1); + if(len == 0) + { + messagex(ctx, LOG_ERR, "clamd disconnected unexpectedly"); + return -1; + } + + if(is_last_word(ctx->line, CLAM_OK, KL(CLAM_OK))) + { + add_to_logline(logline, "status=", "CLEAN"); + messagex(ctx, LOG_DEBUG, "no virus"); + return 0; + } + + if(is_last_word(ctx->line, CLAM_FOUND, KL(CLAM_FOUND))) + { + len = strlen(tempname); + + if(ctx->linelen > len) + add_to_logline(logline, "status=VIRUS:", ctx->line + len + 1); + else + add_to_logline(logline, "status=", "VIRUS"); + + messagex(ctx, LOG_DEBUG, "found virus"); + return 1; + } + + if(is_last_word(ctx->line, CLAM_ERROR, KL(CLAM_ERROR))) + { + messagex(ctx, LOG_ERR, "clamav error: %s", ctx->line); + return -1; + } + + messagex(ctx, LOG_ERR, "unexepected response from clamd: %s", ctx->line); + return -1; +} + + +/* ---------------------------------------------------------------------------------- + * TEMP FILE HANDLING + */ + static int quarantine_virus(clamsmtp_context_t* ctx, char* tempname) { char buf[MAXPATHLEN]; @@ -1238,25 +1285,39 @@ cleanup: return ret; } -static int read_server_response(clamsmtp_context_t* ctx) + +/* ---------------------------------------------------------------------------------- + * NETWORKING + */ + +static int connect_socket(clamsmtp_context_t* ctx, struct sockaddr_any* sany, const char* addrname) { - /* Read response line from the server */ - if(read_line(ctx, &(ctx->server), 0) == -1) - return -1; + int sock = -1; + int ret = 0; - if(ctx->linelen == 0) + if((sock = socket(SANY_TYPE(*sany), SOCK_STREAM, 0)) == -1) + RETURN(-1); + + if(setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &g_timeout, sizeof(g_timeout)) == -1 || + setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, &g_timeout, sizeof(g_timeout)) == -1) + messagex(ctx, LOG_WARNING, "couldn't set timeouts on connection"); + + if(connect(sock, &SANY_ADDR(*sany), SANY_LEN(*sany)) == -1) + RETURN(-1); + +cleanup: + if(ret < 0) { - messagex(ctx, LOG_ERR, "server disconnected unexpectedly"); + if(sock != -1) + shutdown(sock, SHUT_RDWR); - /* Tell the client it went wrong */ - write_data(ctx, &(ctx->client), SMTP_FAILED); - return 0; + message(ctx, LOG_ERR, "couldn't connect to: %s", addrname); + RETURN(-1); } - if(LINE_TOO_LONG(ctx)) - messagex(ctx, LOG_WARNING, "SMTP response line too long. discarded extra"); - - return 0; + ASSERT(sock != -1); + messagex(ctx, LOG_DEBUG, "connected to: %s", addrname); + return sock; } static void read_junk(clamsmtp_context_t* ctx, int fd) @@ -1341,14 +1402,31 @@ static int read_line(clamsmtp_context_t* ctx, int* fd, int trim) break; } - /* Transient errors */ - else if(l == -1 && errno == EAGAIN) - continue; - - /* Fatal errors */ else if(l == -1) { - message(ctx, LOG_ERR, "couldn't read data"); + if(errno == EINTR) + { + /* When the application is quiting */ + if(g_quit) + return -1; + + /* For any other signal we go again */ + continue; + } + + /* + * The basic logic here is that if we've had a fatal error + * reading from the socket once then we shut it down as it's + * no good trying to read from again later. + */ + shutdown(*fd, SHUT_RDWR); + *fd = -1; + + if(errno == EAGAIN) + messagex(ctx, LOG_WARNING, "network read operation timed out"); + else + message(ctx, LOG_ERR, "couldn't read data from socket"); + return -1; } } @@ -1386,16 +1464,29 @@ static int write_data_raw(clamsmtp_context_t* ctx, int* fd, unsigned char* buf, else if(r == -1) { - if(errno == EAGAIN) - continue; - - if(errno == EPIPE) + if(errno == EINTR) { - shutdown(*fd, SHUT_RDWR); - *fd = -1; + /* When the application is quiting */ + if(g_quit) + return -1; + + /* For any other signal we go again */ + continue; } - message(ctx, LOG_ERR, "couldn't write data to socket"); + /* + * The basic logic here is that if we've had a fatal error + * writing to the socket once then we shut it down as it's + * no good trying to write to it again later. + */ + shutdown(*fd, SHUT_RDWR); + *fd = -1; + + if(errno == EAGAIN) + messagex(ctx, LOG_WARNING, "network write operation timed out"); + else + message(ctx, LOG_ERR, "couldn't write data to socket"); + return -1; } } |