Initial version.

1 files changed, 478 insertions, 0 deletions

diff --git a/httpserve.c b/httpserve.c
new file mode 100644
index 0000000..946f4ae
--- /dev/null
+++ b/httpserve.c
@@ -0,0 +1,478 @@
+/*
+
+    httpserve - Serve a directory over HTTP
+
+    Copyright (C) 2024  Ian Cowburn (ianc@noddybox.co.uk)
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+#include <stdlib.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdarg.h>
+
+#include <magic.h>
+
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <netdb.h>
+#include <libgen.h>
+#include <glob.h>
+#include <fcntl.h>
+
+/* ---------------------------------------------------------------------------
+   TYPES AND GLOBALS
+   ---------------------------------------------------------------------------
+*/
+typedef struct
+{
+    int         fd;
+    magic_t     magic;
+} thread_arg_t;
+
+
+/* ---------------------------------------------------------------------------
+   BASE ROUTINES
+   ---------------------------------------------------------------------------
+*/
+static char *Strdup(const char *p)
+{
+    char *ret = strdup(p);
+
+    if (!ret)
+    {
+        perror("strdup");
+        exit(EXIT_FAILURE);
+    }
+
+    return ret;
+}
+
+static void *Malloc(size_t s)
+{
+    void *ret = malloc(s);
+
+    if (!ret)
+    {
+        perror("malloc");
+        exit(EXIT_FAILURE);
+    }
+
+    return ret;
+}
+
+static void *Realloc(void *p, size_t s)
+{
+    void *ret = realloc(p, s);
+
+    if (!ret)
+    {
+        perror("realloc");
+        exit(EXIT_FAILURE);
+    }
+
+    return ret;
+}
+
+static char *PrintStream(char *stream, const char *format, ...)
+{
+    char buff[4096];
+    va_list va;
+    size_t stream_len;
+    size_t buff_len;
+
+    va_start(va, format);
+    vsnprintf(buff, sizeof buff, format, va);
+    va_end(va);
+
+    buff_len = strlen(buff);
+
+    if (stream)
+    {
+        stream_len = strlen(stream);
+    }
+    else
+    {
+        stream_len = 0;
+    }
+
+    stream = Realloc(stream, stream_len + buff_len + 1);
+
+    strcpy(stream + stream_len, buff);
+
+    return stream;
+}
+
+
+/* ---------------------------------------------------------------------------
+   SOCKET ROUTINES
+   ---------------------------------------------------------------------------
+*/
+static int Listen(int port)
+{
+    struct sockaddr_in addr;
+    int fd;
+
+    if ((fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+    {
+	perror("socket");
+        return -1;
+    }
+
+    addr.sin_family = AF_INET;
+    addr.sin_addr.s_addr = INADDR_ANY;
+    addr.sin_port = htons(port);
+
+    if (bind(fd, (void*)&addr, sizeof(addr)) == -1)
+    {
+        perror("bind");
+	return -1;
+    }
+
+    if (listen(fd, 5) == -1)
+    {
+	perror("listen");
+	return -1;
+    }
+
+    return fd;
+}
+
+static int Read(int fd, char *buff, size_t max)
+{
+    int rd;
+    size_t tot = 0;
+
+    while(tot < max)
+    {
+        rd = read(fd, buff + tot, max - tot);
+
+        if (rd < 1)
+        {
+            return 0;
+        }
+
+        tot += rd;
+
+        if (tot < max)
+        {
+            buff[tot] = 0;
+
+            if (tot > 4 && buff[tot - 4] == '\r' && buff[tot - 3] == '\n' &&
+                buff[tot - 2] == '\r' && buff[tot - 1] == '\n')
+            {
+                return 1;
+            }
+        }
+    }
+
+    fprintf(stderr, "HTTP request too big\n");
+    return 0;
+}
+
+
+/* ---------------------------------------------------------------------------
+   HTML ROUTINES
+   ---------------------------------------------------------------------------
+*/
+static void GenerateListing(int fd, const char *protocol)
+{
+    glob_t gl;
+    char *stream = NULL;
+    int f;
+
+    glob("*", 0, NULL, &gl);
+
+    stream = PrintStream(stream, "<!DOCTYPE html>\n<html><head></head><body>");
+
+    for(f = 0; f < gl.gl_pathc; f++)
+    {
+        stream = PrintStream(stream, "<a href=\"%s\">%s</a><br>",
+                                        gl.gl_pathv[f], gl.gl_pathv[f]);
+    }
+
+    stream = PrintStream(stream, "</body></html>");
+
+    dprintf(fd, "%s 200 OK\r\n"
+                "Content-Type: text/html\r\n"
+                "Content-Length: %lu\r\n"
+                "\r\n"
+                "%s", protocol, strlen(stream), stream);
+
+    globfree(&gl);
+    free(stream);
+}
+
+static void GenerateStatus(int fd,
+                           int status,
+                           const char *status_text,
+                           const char *protocol)
+{
+    dprintf(fd, "%s %d %s\r\nContent-Length: 0\r\n\r\n",
+                        protocol, status, status_text);
+}
+
+static void GenerateFile(int fd,
+                         magic_t magic,
+                         const char *path,
+                         const char *protocol)
+{
+    char buff[4096];
+    int file;
+    off_t size;
+    ssize_t len;
+
+    file = open(path, O_RDONLY);
+
+    if (file == -1)
+    {
+        perror("open");
+        GenerateStatus(fd, 404, "Not found", protocol);
+        return;
+    }
+
+    size = lseek(file, 0, SEEK_END);
+    lseek(file, 0, SEEK_SET);
+
+    dprintf(fd, "%s 200 OK\r\n"
+                "Content-Type: %s\r\n"
+                "Content-Length: %lu\r\n"
+                "\r\n", protocol, magic_file(magic, path), (unsigned long)size);
+
+    while((len = read(file, buff, sizeof buff)) > 0)
+    {
+        write(fd, buff, len);
+    }
+
+    close(file);
+}
+
+/* ---------------------------------------------------------------------------
+   HTTP ROUTINES
+   ---------------------------------------------------------------------------
+*/
+static void DecodeURL(char *dest, const char *url)
+{
+    while(*url)
+    {
+        char num[3]={0};
+
+        switch(*url)
+        {
+            case '%':
+                num[0] = url[1];
+                num[1] = url[2];
+                *dest++ = (char)strtol(num, NULL, 16);
+                url += 3;
+                break;
+
+            case '+':
+                *dest++ = ' ';
+                url++;
+                break;
+
+            default:
+                *dest++ = *url++;
+                break;
+        }
+    }
+
+    *dest = 0;
+}
+
+static int ParseRequest(char *request,
+                        char **method,
+                        char **path,
+                        char **protocol,
+                        int *close)
+{
+    char *tok[3] = {0};
+    char *last;
+    int f;
+
+    *method = NULL;
+    *path = NULL;
+    *protocol = NULL;
+    *close = 0;
+
+    if ((tok[0] = strtok_r(request, " ", &last)) &&
+        (tok[1] = strtok_r(NULL, " ", &last)) &&
+        (tok[2] = strtok_r(NULL, " \r\n", &last)))
+    {
+        char *tmppath;
+
+        *method = tok[0];
+        *path = tok[1];
+        *protocol = tok[2];
+
+        /* This is slightly dodgy as hell, but should work
+        */
+        *close = (strstr(*protocol + strlen(*protocol) + 3,
+                    "Connection: close\r\n") ||
+                  strcmp(*protocol, "HTTP/1.0") == 0);
+
+        tmppath = Strdup(*path);
+        DecodeURL(*path, tmppath);
+        free(tmppath);
+
+        return 1;
+    }
+
+    return 0;
+}
+
+
+/* ---------------------------------------------------------------------------
+   THREAD CODE
+   ---------------------------------------------------------------------------
+*/
+static void *ThreadCode(void *p)
+{
+    char buff[4096];
+    char *method = NULL;
+    char *path = NULL;
+    char *protocol = NULL;
+    int close_connection = 0;
+    thread_arg_t *args = p;
+
+    while (Read(args->fd, buff, sizeof buff) && !close_connection)
+    {
+        if (ParseRequest(buff, &method, &path,
+                            &protocol, &close_connection))
+        {
+            if (strcmp(method, "GET") == 0)
+            {
+                printf("%s %s %s\n", method, path, protocol);
+
+                path = basename(path);
+
+                if (strcmp(path, "/") == 0)
+                {
+                    printf("Generate listing for /\n");
+                    GenerateListing(args->fd, protocol);
+                }
+                else if (access(path, R_OK) == 0)
+                {
+                    printf("Generating download for %s\n", path);
+                    GenerateFile(args->fd, args->magic, path, protocol);
+                }
+                else
+                {
+                    printf("File not found - returning 404\n");
+                    GenerateStatus(args->fd, 404, "Not found", protocol);
+                }
+            }
+            else
+            {
+                printf("Method %s not supported\n", method);
+                GenerateStatus(args->fd, 501, "Not implemented", protocol);
+            }
+        }
+        else
+        {
+            printf("Bad request %s\n", method);
+        }
+    }
+
+    printf("Connection closed on %d\n", args->fd);
+    close(args->fd);
+
+    return NULL;
+}
+
+
+/* ---------------------------------------------------------------------------
+   MAIN
+   ---------------------------------------------------------------------------
+*/
+int main(int argc, char *argv[])
+{
+    magic_t magic;
+    int port = 80;
+    int opt;
+    int sock;
+    const char *dir=".";
+
+    while((opt = getopt(argc, argv, "p:d:")) != -1)
+    {
+        switch(opt)
+        {
+            case 'p':
+                port = atoi(optarg);
+                break;
+
+            case 'd':
+                dir = optarg;
+                break;
+
+            default:
+                fprintf(stderr, "%s: usage %s [-p port] [-d dir]\n",
+                            argv[0], argv[0]);
+                return EXIT_FAILURE;
+        }
+    }
+
+    magic = magic_open(MAGIC_MIME_TYPE);
+
+    if (!magic)
+    {
+        fprintf(stderr, "%s: Failed to open magic library\n", argv[0]);
+    }
+
+    magic_load(magic, NULL);
+
+    if ((sock = Listen(port)) == -1)
+    {
+        return EXIT_FAILURE;
+    }
+
+    chdir(dir);
+
+    printf("Serving up %s on %d\n", dir, port);
+
+    while(1)
+    {
+        pthread_t thread;
+        thread_arg_t *thread_args;
+        int fd;
+
+        if ((fd = accept(sock, NULL, 0)) == -1)
+        {
+            perror("accept");
+            close(sock);
+            return EXIT_FAILURE;
+        }
+
+        printf("Accepted connection on %d\n", fd);
+
+        thread_args = Malloc(sizeof *thread_args);
+        thread_args->fd = fd;
+        thread_args->magic = magic;
+
+        pthread_create(&thread, NULL, ThreadCode, thread_args);
+        pthread_detach(thread);
+    }
+
+    return EXIT_SUCCESS;
+}
+
+/*
+vim: ai sw=4 ts=8 expandtab
+*/