Add global error handling

Makefile

@@ -63,7 +63,7 @@ bin/sesimos: bin/server.o bin/logger.o bin/cache_handler.o bin/async.o bin/worke
              bin/lib/http_static.o bin/res/default.o bin/res/proxy.o bin/res/style.o \
              bin/res/icon_error.o bin/res/icon_info.o bin/res/icon_success.o bin/res/icon_warning.o \
              bin/res/globe.o \
-             bin/lib/compress.o bin/lib/config.o bin/lib/fastcgi.o bin/lib/geoip.o \
+             bin/lib/compress.o bin/lib/config.o bin/lib/fastcgi.o bin/lib/geoip.o bin/lib/error.o \
              bin/lib/http.o  bin/lib/proxy.o bin/lib/sock.o bin/lib/uri.o \
              bin/lib/utils.o bin/lib/websocket.o bin/lib/mpmc.o bin/lib/list.o
 	$(CC) -o $@ $^ $(CFLAGS) $(LDFLAGS)
@@ -99,6 +99,8 @@ bin/lib/config.o: src/lib/config.h src/lib/utils.h src/lib/uri.h src/logger.h
 bin/lib/fastcgi.o: src/lib/fastcgi.h src/server.h src/lib/utils.h src/lib/compress.h src/lib/http.h \
                    src/lib/uri.h src/lib/include/fastcgi.h src/logger.h
 
+bin/lib/error.o: src/lib/error.h
+
 bin/lib/geoip.o: src/lib/geoip.h
 
 bin/lib/http.o: src/lib/http.h src/lib/utils.h src/lib/compress.h src/lib/sock.h src/logger.h

src/lib/error.c

@@ -0,0 +1,103 @@
+/**
+ * sesimos - secure, simple, modern web server
+ * @brief Error interface
+ * @file src/lib/error.c
+ * @author Lorenz Stechauner
+ * @date 2023-01-08
+ */
+
+#include "error.h"
+#include "http.h"
+
+#include <errno.h>
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include <maxminddb.h>
+
+static const char *error_ssl_strerror(int err) {
+    switch (err) {
+        case SSL_ERROR_ZERO_RETURN:
+            return "closed";
+        case SSL_ERROR_WANT_READ:
+            return "want read";
+        case SSL_ERROR_WANT_WRITE:
+            return "want write";
+        case SSL_ERROR_WANT_CONNECT:
+            return "want connect";
+        case SSL_ERROR_WANT_ACCEPT:
+            return "want accept";
+        case SSL_ERROR_WANT_X509_LOOKUP:
+            return "want x509 lookup";
+        case SSL_ERROR_WANT_ASYNC:
+            return "want async";
+        case SSL_ERROR_WANT_ASYNC_JOB:
+            return "want async job";
+        case SSL_ERROR_WANT_CLIENT_HELLO_CB:
+            return "want client hello callback";
+        case SSL_ERROR_WANT_RETRY_VERIFY:
+            return "want retry verify";
+        case SSL_ERROR_SSL:
+            return ERR_reason_error_string(ERR_get_error());
+        default:
+            return "unknown error";
+    }
+}
+
+static const char *error_http_strerror(int err) {
+    switch (err) {
+        default:
+            return "unknown error";
+    }
+}
+
+const char *error_str(int err_no, char *buf, int buf_len) {
+    buf[0] = 0;
+    unsigned char mode = (unsigned char) (err_no >> 24);
+    int e = err_no & 0x00FFFFFF;
+    if (mode == 0x00) {
+        // normal
+        strerror_r(e, buf, buf_len);
+        return buf;
+    } else if (mode == 0x01) {
+        // ssl
+        return error_ssl_strerror(e);
+    } else if (mode == 0x02) {
+        // mmdb
+        return MMDB_strerror(e);
+    } else if (mode == 0x03) {
+        // http
+        return error_http_strerror(e);
+    }
+    return buf;
+}
+
+void error_ssl(int err) {
+    if (err == SSL_ERROR_NONE) {
+        errno = 0;
+    } else if (err == SSL_ERROR_SYSCALL) {
+        // errno already set
+    } else {
+        errno = 0x01000000 | err;
+    }
+}
+
+void error_mmdb(int err) {
+    if (err == MMDB_SUCCESS) {
+        errno = 0;
+    } else if (err == MMDB_IO_ERROR) {
+        // errno already set
+    } else {
+        errno = 0x02000000 | err;
+    }
+}
+
+int error_http(int err) {
+    if (err == 0) {
+        errno = 0;
+    } else if (err == HTTP_ERROR_SYSCALL) {
+        // errno already set
+    } else {
+        errno = 0x03000000 | err;
+    }
+    return -1;
+}

src/lib/error.h

@@ -0,0 +1,20 @@
+/**
+ * sesimos - secure, simple, modern web server
+ * @brief Error interface (header fie)
+ * @file src/lib/error.h
+ * @author Lorenz Stechauner
+ * @date 2023-01-08
+ */
+
+#ifndef SESIMOS_ERROR_H
+#define SESIMOS_ERROR_H
+
+const char *error_str(int err_no, char *buf, int buf_len);
+
+void error_ssl(int err);
+
+void error_mmdb(int err);
+
+int error_http(int err);
+
+#endif //SESIMOS_ERROR_H

src/lib/fastcgi.c

@@ -593,7 +593,7 @@ int fastcgi_receive(fastcgi_cnx_t *conn, sock *client, unsigned long len) {
     while (rcv_len < len) {
         ret = sock_recv(client, buf, sizeof(buf), 0);
         if (ret <= 0) {
-            error("Unable to receive: %s", sock_strerror(client));
+            error("Unable to receive");
             return -1;
         }
 

src/lib/geoip.c

@@ -8,6 +8,7 @@
 
 #include "geoip.h"
 #include "../logger.h"
+#include "error.h"
 #include <memory.h>
 #include <dirent.h>
 
@@ -101,7 +102,8 @@ int geoip_init(const char *directory) {
 
         sprintf(buf, "%s/%s", directory, entry->d_name);
         if ((status = MMDB_open(buf, 0, &mmdbs[i])) != MMDB_SUCCESS) {
-            critical("Unable to initialize geoip: Unable to open .mmdb file: %s", MMDB_strerror(status));
+            error_mmdb(status);
+            critical("Unable to initialize geoip: Unable to open .mmdb file");
             closedir(geoip_dir);
             return 1;
         }
@@ -164,7 +166,8 @@ int geoip_lookup_json(struct sockaddr *addr, char *json, long len) {
         int mmdb_res;
         MMDB_lookup_result_s result = MMDB_lookup_sockaddr(&mmdbs[i], addr, &mmdb_res);
         if (mmdb_res != MMDB_SUCCESS) {
-            error("Unable to lookup geoip info: %s", MMDB_strerror(mmdb_res));
+            error_mmdb(mmdb_res);
+            error("Unable to lookup geoip info");
             continue;
         } else if (!result.found_entry) {
             continue;
@@ -172,7 +175,8 @@ int geoip_lookup_json(struct sockaddr *addr, char *json, long len) {
 
         MMDB_entry_data_list_s *list;
         if ((mmdb_res = MMDB_get_entry_data_list(&result.entry, &list)) != MMDB_SUCCESS) {
-            error("Unable to lookup geoip info: %s", MMDB_strerror(mmdb_res));
+            error_mmdb(mmdb_res);
+            error("Unable to lookup geoip info");
             continue;
         }
 

src/lib/http.c

@@ -227,7 +227,7 @@ int http_receive_request(sock *client, http_req *req) {
 
     rcv_len = sock_recv(client, buf, CLIENT_MAX_HEADER_SIZE - 1, MSG_PEEK);
     if (rcv_len <= 0) {
-        error("Unable to receive http header: %s", sock_strerror(client));
+        error("Unable to receive http header");
         return -1;
     }
     buf[rcv_len] = 0;

src/lib/http.h

@@ -45,6 +45,10 @@
 #define HTTP_TYPE_CLIENT_ERROR  4
 #define HTTP_TYPE_SERVER_ERROR  5
 
+#define HTTP_ERROR_GENERAL 1
+#define HTTP_ERROR_SYSCALL 2
+#define HTTP_ERROR_TOO_MANY_HEADER_FIELDS 3
+
 #ifndef SERVER_STR
 #   define SERVER_STR "sesimos"
 #endif

src/lib/proxy.c

@@ -13,6 +13,7 @@
 #include "utils.h"
 #include "compress.h"
 #include "config.h"
+#include "error.h"
 
 #include <openssl/ssl.h>
 #include <string.h>
@@ -293,7 +294,7 @@ int proxy_response_header(http_req *req, http_res *res, host_config_t *conf) {
 }
 
 int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_status_ctx *ctx, host_config_t *conf, sock *client, http_status *custom_status, char *err_msg) {
-    char buffer[CHUNK_SIZE];
+    char buffer[CHUNK_SIZE], err_buf[256];
     const char *connection, *upgrade, *ws_version;
     long ret;
     int tries = 0, retry = 0;
@@ -360,8 +361,8 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
             res->status = http_get_status(500);
             ctx->origin = INTERNAL;
         }
-        error("Unable to connect to [%s]:%i: %s", buffer, conf->proxy.port, strerror(errno));
+        error("Unable to connect to [%s]:%i", buffer, conf->proxy.port);
-        sprintf(err_msg, "Unable to connect to server: %s.", strerror(errno));
+        sprintf(err_msg, "Unable to connect to server: %s.", error_str(errno, err_buf, sizeof(err_buf)));
         goto proxy_err;
     }
 
@@ -370,7 +371,7 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
         res->status = http_get_status(500);
         ctx->origin = INTERNAL;
         error("Unable to set timeout for reverse proxy socket");
-        sprintf(err_msg, "Unable to set timeout for reverse proxy socket: %s", strerror(errno));
+        sprintf(err_msg, "Unable to set timeout for reverse proxy socket: %s", error_str(errno, err_buf, sizeof(err_buf)));
         goto proxy_err;
     }
 
@@ -380,17 +381,15 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
         SSL_set_connect_state(proxy->proxy.ssl);
 
         ret = SSL_do_handshake(proxy->proxy.ssl);
-        proxy->proxy._last_ret = ret;
+        if (ret != 1) {
-        proxy->proxy._errno = errno;
+            error_ssl(SSL_get_error(proxy->proxy.ssl, (int) ret));
-        proxy->proxy._ssl_error = ERR_get_error();
-        proxy->proxy.enc = 1;
-        if (ret < 0) {
             res->status = http_get_status(502);
             ctx->origin = SERVER_REQ;
-            error("Unable to perform handshake: %s", sock_strerror(&proxy->proxy));
+            error("Unable to perform handshake");
-            sprintf(err_msg, "Unable to perform handshake: %s.", sock_strerror(&proxy->proxy));
+            sprintf(err_msg, "Unable to perform handshake: %s.", error_str(errno, err_buf, sizeof(err_buf)));
             goto proxy_err;
         }
+        proxy->proxy.enc = 1;
     }
 
     proxy->initialized = 1;
@@ -425,8 +424,8 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
     if (ret < 0) {
         res->status = http_get_status(502);
         ctx->origin = SERVER_REQ;
-        error("Unable to send request to server (1): %s", sock_strerror(&proxy->proxy));
+        error("Unable to send request to server (1)");
-        sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&proxy->proxy));
+        sprintf(err_msg, "Unable to send request to server: %s.", error_str(errno, err_buf, sizeof(err_buf)));
         retry = tries < 4;
         goto proxy_err;
     }
@@ -446,15 +445,15 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
         if (ret == -1) {
             res->status = http_get_status(502);
             ctx->origin = SERVER_REQ;
-            error("Unable to send request to server (2): %s", sock_strerror(&proxy->proxy));
+            error("Unable to send request to server (2)");
-            sprintf(err_msg, "Unable to send request to server: %s.", sock_strerror(&proxy->proxy));
+            sprintf(err_msg, "Unable to send request to server: %s.", error_str(errno, err_buf, sizeof(err_buf)));
             retry = tries < 4;
             goto proxy_err;
         } else if (ret == -2) {
             res->status = http_get_status(400);
             ctx->origin = CLIENT_REQ;
-            error("Unable to receive request from client: %s", sock_strerror(client));
+            error("Unable to receive request from client");
-            sprintf(err_msg, "Unable to receive request from client: %s.", sock_strerror(client));
+            sprintf(err_msg, "Unable to receive request from client: %s.", error_str(errno, err_buf, sizeof(err_buf)));
             return -1;
         }
         res->status = http_get_status(500);
@@ -465,18 +464,16 @@ int proxy_init(proxy_ctx_t **proxy_ptr, http_req *req, http_res *res, http_statu
 
     ret = sock_recv(&proxy->proxy, buffer, sizeof(buffer), MSG_PEEK);
     if (ret <= 0) {
-        int enc_err = sock_enc_error(&proxy->proxy);
+        int enc_err = errno & 0x00FFFFFFFF;
-        if (errno == EAGAIN || errno == EINPROGRESS || enc_err == SSL_ERROR_WANT_READ ||
+        if (errno == EAGAIN || errno == EINPROGRESS || enc_err == SSL_ERROR_WANT_READ || enc_err == SSL_ERROR_WANT_WRITE) {
-            enc_err == SSL_ERROR_WANT_WRITE)
-        {
             res->status = http_get_status(504);
             ctx->origin = SERVER_RES;
         } else {
             res->status = http_get_status(502);
             ctx->origin = SERVER_RES;
         }
-        error("Unable to receive response from server: %s", sock_strerror(&proxy->proxy));
+        error("Unable to receive response from server");
-        sprintf(err_msg, "Unable to receive response from server: %s.", sock_strerror(&proxy->proxy));
+        sprintf(err_msg, "Unable to receive response from server: %s.", error_str(errno, err_buf, sizeof(err_buf)));
         retry = tries < 4;
         goto proxy_err;
     }
@@ -595,7 +592,7 @@ int proxy_send(proxy_ctx_t *proxy, sock *client, unsigned long len_to_send, int
                 if (ret == -1) {
                     error("Unable to receive from server: Malformed chunk header");
                 } else {
-                    error("Unable to receive from server: %s", sock_strerror(&proxy->proxy));
+                    error("Unable to receive from server");
                 }
                 break;
             }
@@ -615,7 +612,7 @@ int proxy_send(proxy_ctx_t *proxy, sock *client, unsigned long len_to_send, int
             unsigned long avail_in, avail_out;
             ret = sock_recv(&proxy->proxy, buffer, CHUNK_SIZE < (len_to_send - snd_len) ? CHUNK_SIZE : len_to_send - snd_len, 0);
             if (ret <= 0) {
-                error("Unable to receive from server: %s", sock_strerror(&proxy->proxy));
+                error("Unable to receive from server");
                 break;
             }
             len = ret;
@@ -646,7 +643,7 @@ int proxy_send(proxy_ctx_t *proxy, sock *client, unsigned long len_to_send, int
                     if (flags & PROXY_CHUNKED) ret = sock_send(client, "\r\n", 2, 0);
                     if (ret <= 0) {
                         err:
-                        error("Unable to send: %s", sock_strerror(client));
+                        error("Unable to send");
                         break;
                     }
                 }
@@ -663,7 +660,7 @@ int proxy_send(proxy_ctx_t *proxy, sock *client, unsigned long len_to_send, int
     if (flags & PROXY_CHUNKED) {
         ret = sock_send(client, "0\r\n\r\n", 5, 0);
         if (ret <= 0) {
-            error("Unable to send: %s", sock_strerror(client));
+            error("Unable to send");
             return -1;
         }
     }

src/lib/sock.c

@@ -8,57 +8,14 @@
 
 #include "sock.h"
 #include "utils.h"
+#include "error.h"
 
-#include <openssl/err.h>
+#include <errno.h>
 #include <openssl/ssl.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <unistd.h>
 
-
-int sock_enc_error(sock *s) {
-    return (int) s->enc ? SSL_get_error(s->ssl, (int) s->_last_ret) : 0;
-}
-
-const char *sock_strerror(sock *s) {
-    // FIXME sock_strerror not Thread Safe!
-    //       (and ugly)
-    errno = 0;
-    if (s->_last_ret == 0) {
-        return "closed";
-    } else if (s->enc) {
-        if (s->_last_ret > 0) {
-            return NULL;
-        }
-        const char *err1 = ERR_reason_error_string(s->_ssl_error);
-        const char *err2 = strerror(s->_errno);
-        switch (sock_enc_error(s)) {
-            case SSL_ERROR_NONE:
-                return NULL;
-            case SSL_ERROR_ZERO_RETURN:
-                return "closed";
-            case SSL_ERROR_WANT_READ:
-                return "want read";
-            case SSL_ERROR_WANT_WRITE:
-                return "want write";
-            case SSL_ERROR_WANT_CONNECT:
-                return "want connect";
-            case SSL_ERROR_WANT_ACCEPT:
-                return "want accept";
-            case SSL_ERROR_WANT_X509_LOOKUP:
-                return "want x509 lookup";
-            case SSL_ERROR_SYSCALL:
-                return ((s->_ssl_error == 0) ? ((s->_last_ret == 0) ? "protocol violation" : err2) : err1);
-            case SSL_ERROR_SSL:
-                return err1;
-            default:
-                return "unknown error";
-        }
-    } else {
-        return strerror(s->_errno);
-    }
-}
-
 int sock_set_socket_timeout_micros(sock *s, long recv_micros, long send_micros) {
     struct timeval recv_to = {.tv_sec = recv_micros / 1000000, .tv_usec = recv_micros % 1000000},
                    send_to = {.tv_sec = send_micros / 1000000, .tv_usec = send_micros % 1000000};
@@ -92,12 +49,11 @@ long sock_send(sock *s, void *buf, unsigned long len, int flags) {
     long ret;
     if (s->enc) {
         ret = SSL_write(s->ssl, buf, (int) len);
-        s->_ssl_error = ERR_get_error();
+        if (ret <= 0) error_ssl(SSL_get_error(s->ssl, (int) ret));
     } else {
         ret = send(s->socket, buf, len, flags);
     }
-    s->_last_ret = ret;
+
-    s->_errno = errno;
     if (ret >= 0) {
         s->ts_last = clock_micros();
         return ret;
@@ -111,12 +67,11 @@ long sock_recv(sock *s, void *buf, unsigned long len, int flags) {
     if (s->enc) {
         int (*func)(SSL*, void*, int) = (flags & MSG_PEEK) ? SSL_peek : SSL_read;
         ret = func(s->ssl, buf, (int) len);
-        s->_ssl_error = ERR_get_error();
+        if (ret <= 0) error_ssl(SSL_get_error(s->ssl, (int) ret));
     } else {
         ret = recv(s->socket, buf, len, flags);
     }
-    s->_last_ret = ret;
+
-    s->_errno = errno;
     if (ret >= 0) {
         s->ts_last = clock_micros();
         return ret;
@@ -164,7 +119,7 @@ long sock_splice_chunked(sock *dst, sock *src, void *buf, unsigned long buf_len)
 int sock_close(sock *s) {
     int e = errno;
     if (s->enc && s->ssl != NULL) {
-        if (s->_last_ret >= 0) SSL_shutdown(s->ssl);
+        SSL_shutdown(s->ssl);
         SSL_free(s->ssl);
         s->ssl = NULL;
     }

src/lib/sock.h

@@ -24,15 +24,8 @@ typedef struct {
     SSL_CTX *ctx;
     SSL *ssl;
     long ts_start, ts_last, timeout_us;
-    long _last_ret;
-    int _errno;
-    unsigned long _ssl_error;
 } sock;
 
-int sock_enc_error(sock *s);
-
-const char *sock_strerror(sock *s);
-
 int sock_set_socket_timeout_micros(sock *s, long recv_micros, long send_micros);
 
 int sock_set_socket_timeout(sock *s, double sec);

src/logger.c

@@ -8,6 +8,7 @@
 
 #include "logger.h"
 #include "lib/utils.h"
+#include "lib/error.h"
 
 #include <stdio.h>
 #include <pthread.h>
@@ -59,8 +60,8 @@ static const char *level_keywords[] = {
 
 static void err(const char *restrict msg) {
     char err_buf[64];
-    strerror_r(errno, err_buf, sizeof(err_buf));
+    fprintf(stderr, ERR_STR LOG_PREFIX " %s: %s" CLR_STR "\n", "logger",
-    fprintf(stderr, ERR_STR LOG_PREFIX " %s: %s" CLR_STR "\n", "logger", level_keywords[LOG_CRITICAL], msg, err_buf);
+            level_keywords[LOG_CRITICAL], msg, error_str(errno, err_buf, sizeof(err_buf)));
 }
 
 void logmsgf(log_lvl_t level, const char *restrict format, ...) {
@@ -71,8 +72,7 @@ void logmsgf(log_lvl_t level, const char *restrict format, ...) {
 
     const char *color = (level <= LOG_ERROR) ? ERR_STR : ((level <= LOG_WARNING) ? WRN_STR : "");
     if (errno != 0) {
-        strerror_r(errno, err_buf, sizeof(err_buf));
+        snprintf(buf, sizeof(buf), "%s%s: %s" CLR_STR, color, format, error_str(errno, err_buf, sizeof(err_buf)));
-        snprintf(buf, sizeof(buf), "%s%s: %s" CLR_STR, color, format, err_buf);
     } else {
         snprintf(buf, sizeof(buf), "%s%s" CLR_STR, color, format);
     }

src/worker/request_handler.c

@@ -75,7 +75,6 @@ static int request_handler(client_ctx_t *ctx) {
     sock *client = &ctx->socket;
     char *err_msg = ctx->err_msg;
     http_res *res = &ctx->res;
-    http_status_ctx *status = &ctx->status;
 
     long ret;
     char buf0[1024], buf1[1024];
@@ -353,7 +352,7 @@ int respond(client_ctx_t *ctx) {
         if (ctx->msg_buf != NULL) {
             ret = sock_send(client, ctx->msg_buf, ctx->content_length, 0);
             if (ret <= 0) {
-                error("Unable to send: %s", sock_strerror(client));
+                error("Unable to send");
             }
         } else if (ctx->file != NULL) {
             unsigned long len, snd_len = 0;
@@ -364,7 +363,7 @@ int respond(client_ctx_t *ctx) {
                 }
                 ret = sock_send(client, buffer, len, feof(ctx->file) ? 0 : MSG_MORE);
                 if (ret <= 0) {
-                    error("Unable to send: %s", sock_strerror(client));
+                    error("Unable to send");
                     break;
                 }
                 snd_len += ret;

src/worker/tcp_acceptor.c

@@ -12,6 +12,7 @@
 #include "../lib/geoip.h"
 #include "../workers.h"
 #include "../server.h"
+#include "../lib/error.h"
 
 #include <string.h>
 #include <errno.h>
@@ -63,7 +64,7 @@ static int tcp_acceptor(client_ctx_t *ctx) {
         sprintf(buf, "dig @%s +short +time=1 -x %s", config.dns_server, ctx->socket.addr);
         FILE *dig = popen(buf, "r");
         if (dig == NULL) {
-            error("Unable to start dig: %s", strerror(errno));
+            error("Unable to start dig: %s");
             goto dig_err;
         }
         unsigned long read = fread(buf, 1, sizeof(buf), dig);
@@ -101,11 +102,9 @@ static int tcp_acceptor(client_ctx_t *ctx) {
         SSL_set_accept_state(client->ssl);
 
         ret = SSL_accept(client->ssl);
-        client->_last_ret = ret;
+        if (ret != 1) {
-        client->_errno = errno;
+            error_ssl(SSL_get_error(client->ssl, ret));
-        client->_ssl_error = ERR_get_error();
+            info("Unable to perform handshake");
-        if (ret <= 0) {
-            info("Unable to perform handshake: %s", sock_strerror(client));
             return - 1;
         }
         client->ts_last = clock_micros();