Mercurial > urweb
diff src/c/request.c @ 853:19fdeef40ada
Factor out common request functionality, in preparation for supporting different protocols
author | Adam Chlipala <adamc@hcoop.net> |
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date | Tue, 23 Jun 2009 14:05:12 -0400 |
parents | |
children | 158d980889ac |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/c/request.c Tue Jun 23 14:05:12 2009 -0400 @@ -0,0 +1,467 @@ +#define _GNU_SOURCE + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <unistd.h> +#include <signal.h> + +#include <pthread.h> + +#include <mhash.h> + +#include "urweb.h" + +#define MAX_RETRIES 5 + +static int try_rollback(uw_context ctx) { + int r = uw_rollback(ctx); + + if (r) { + printf("Error running SQL ROLLBACK\n"); + uw_reset(ctx); + uw_write(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + uw_write(ctx, "Content-type: text/plain\r\n\r\n"); + uw_write(ctx, "Error running SQL ROLLBACK\n"); + } + + return r; +} + +uw_context uw_request_new_context() { + uw_context ctx = uw_init(); + int retries_left = MAX_RETRIES; + + while (1) { + failure_kind fk = uw_begin_init(ctx); + + if (fk == SUCCESS) { + printf("Database connection initialized.\n"); + break; + } else if (fk == BOUNDED_RETRY) { + if (retries_left) { + printf("Initialization error triggers bounded retry: %s\n", uw_error_message(ctx)); + --retries_left; + } else { + printf("Fatal initialization error (out of retries): %s\n", uw_error_message(ctx)); + uw_free(ctx); + return NULL; + } + } else if (fk == UNLIMITED_RETRY) + printf("Initialization error triggers unlimited retry: %s\n", uw_error_message(ctx)); + else if (fk == FATAL) { + printf("Fatal initialization error: %s\n", uw_error_message(ctx)); + uw_free(ctx); + return NULL; + } else { + printf("Unknown uw_begin_init return code!\n"); + uw_free(ctx); + return NULL; + } + } + + return ctx; +} + +#define KEYSIZE 16 +#define PASSSIZE 4 + +#define HASH_ALGORITHM MHASH_SHA256 +#define HASH_BLOCKSIZE 32 +#define KEYGEN_ALGORITHM KEYGEN_MCRYPT + +int uw_hash_blocksize = HASH_BLOCKSIZE; + +static int password[PASSSIZE]; +static unsigned char private_key[KEYSIZE]; + +static void init_crypto() { + KEYGEN kg = {{HASH_ALGORITHM, HASH_ALGORITHM}}; + int i; + + assert(mhash_get_block_size(HASH_ALGORITHM) == HASH_BLOCKSIZE); + + for (i = 0; i < PASSSIZE; ++i) + password[i] = rand(); + + if (mhash_keygen_ext(KEYGEN_ALGORITHM, kg, + private_key, sizeof(private_key), + (unsigned char*)password, sizeof(password)) < 0) { + printf("Key generation failed\n"); + exit(1); + } +} + +void uw_request_init() { + uw_context ctx; + failure_kind fk; + + uw_global_init(); + + ctx = uw_request_new_context(); + + if (!ctx) + exit(1); + + for (fk = uw_initialize(ctx); fk == UNLIMITED_RETRY; fk = uw_initialize(ctx)) { + printf("Unlimited retry during init: %s\n", uw_error_message(ctx)); + uw_db_rollback(ctx); + uw_reset(ctx); + } + + if (fk != SUCCESS) { + printf("Failed to initialize database! %s\n", uw_error_message(ctx)); + uw_db_rollback(ctx); + exit(1); + } + + uw_free(ctx); + + init_crypto(); +} + +void uw_sign(const char *in, char *out) { + MHASH td; + + td = mhash_hmac_init(HASH_ALGORITHM, private_key, sizeof(private_key), + mhash_get_hash_pblock(HASH_ALGORITHM)); + + mhash(td, in, strlen(in)); + if (mhash_hmac_deinit(td, out) < 0) + printf("Signing failed"); +} + +typedef struct uw_rc { + size_t path_copy_size; + char *path_copy; +} *uw_request_context; + +uw_request_context uw_new_request_context(void) { + uw_request_context r = malloc(sizeof(struct uw_rc)); + r->path_copy_size = 0; + r->path_copy = malloc(0); + return r; +} + +void uw_free_request_context(uw_request_context r) { + free(r->path_copy); + free(r); +} + +request_result uw_request(uw_request_context rc, uw_context ctx, char *request, size_t request_len, int sock) { + int retries_left = MAX_RETRIES; + char *s; + failure_kind fk; + int is_post = 0, do_normal_send = 1; + char *boundary = NULL; + size_t boundary_len; + char *cmd, *path, *headers, *inputs, *after_headers; + + if (!(s = strstr(request, "\r\n\r\n"))) { + fprintf(stderr, "No end of headers found in request\n"); + return FAILED; + } + + s[2] = 0; + after_headers = s + 4; + + if (!(s = strstr(request, "\r\n"))) { + fprintf(stderr, "No newline in request\n"); + return FAILED; + } + + *s = 0; + headers = s + 2; + cmd = s = request; + + if (!strsep(&s, " ")) { + fprintf(stderr, "No first space in HTTP command\n"); + return FAILED; + } + + uw_set_headers(ctx, headers); + + if (!strcmp(cmd, "POST")) { + char *clen_s = uw_Basis_requestHeader(ctx, "Content-length"); + if (!clen_s) { + fprintf(stderr, "No Content-length with POST\n"); + return FAILED; + } + int clen = atoi(clen_s); + if (clen < 0) { + fprintf(stderr, "Negative Content-length with POST\n"); + return FAILED; + } + + if (request + request_len - after_headers < clen) { + fprintf(stderr, "Request doesn't contain all POST data (according to Content-Length)\n"); + return FAILED; + } + + is_post = 1; + + clen_s = uw_Basis_requestHeader(ctx, "Content-type"); + if (clen_s && !strncasecmp(clen_s, "multipart/form-data", 19)) { + if (strncasecmp(clen_s + 19, "; boundary=", 11)) { + fprintf(stderr, "Bad multipart boundary spec"); + return FAILED; + } + + boundary = clen_s + 28; + boundary[0] = '-'; + boundary[1] = '-'; + boundary_len = strlen(boundary); + } + } else if (strcmp(cmd, "GET")) { + fprintf(stderr, "Not ready for non-GET/POST command: %s\n", cmd); + return FAILED; + } + + path = s; + if (!strsep(&s, " ")) { + fprintf(stderr, "No second space in HTTP command\n"); + return FAILED; + } + + if (!strcmp(path, "/.msgs")) { + char *id = uw_Basis_requestHeader(ctx, "UrWeb-Client"); + char *pass = uw_Basis_requestHeader(ctx, "UrWeb-Pass"); + + if (sock < 0) { + fprintf(stderr, ".msgs requested, but not socket supplied\n"); + return FAILED; + } + + if (id && pass) { + unsigned idn = atoi(id); + uw_client_connect(idn, atoi(pass), sock); + fprintf(stderr, "Processed request for messages by client %u\n\n", idn); + return KEEP_OPEN; + } + else { + fprintf(stderr, "Missing fields in .msgs request: %s, %s\n\n", id, pass); + return FAILED; + } + } + + if (boundary) { + char *part = after_headers, *after_sub_headers, *header, *after_header; + size_t part_len; + + part = strstr(part, boundary); + if (!part) { + fprintf(stderr, "Missing first multipart boundary\n"); + return FAILED; + } + part += boundary_len; + + while (1) { + char *name = NULL, *filename = NULL, *type = NULL; + + if (part[0] == '-' && part[1] == '-') + break; + + if (*part != '\r') { + fprintf(stderr, "No \\r after multipart boundary\n"); + return FAILED; + } + ++part; + if (*part != '\n') { + fprintf(stderr, "No \\n after multipart boundary\n"); + return FAILED; + } + ++part; + + if (!(after_sub_headers = strstr(part, "\r\n\r\n"))) { + fprintf(stderr, "Missing end of headers after multipart boundary\n"); + return FAILED; + } + after_sub_headers[2] = 0; + after_sub_headers += 4; + + for (header = part; after_header = strstr(header, "\r\n"); header = after_header + 2) { + char *colon, *after_colon; + + *after_header = 0; + if (!(colon = strchr(header, ':'))) { + fprintf(stderr, "Missing colon in multipart sub-header\n"); + return FAILED; + } + *colon++ = 0; + if (*colon++ != ' ') { + fprintf(stderr, "No space after colon in multipart sub-header\n"); + return FAILED; + } + + if (!strcasecmp(header, "Content-Disposition")) { + if (strncmp(colon, "form-data; ", 11)) { + fprintf(stderr, "Multipart data is not \"form-data\"\n"); + return FAILED; + } + + for (colon += 11; after_colon = strchr(colon, '='); colon = after_colon) { + char *data; + after_colon[0] = 0; + if (after_colon[1] != '"') { + fprintf(stderr, "Disposition setting is missing initial quote\n"); + return FAILED; + } + data = after_colon+2; + if (!(after_colon = strchr(data, '"'))) { + fprintf(stderr, "Disposition setting is missing final quote\n"); + return FAILED; + } + after_colon[0] = 0; + ++after_colon; + if (after_colon[0] == ';' && after_colon[1] == ' ') + after_colon += 2; + + if (!strcasecmp(colon, "name")) + name = data; + else if (!strcasecmp(colon, "filename")) + filename = data; + } + } else if (!strcasecmp(header, "Content-Type")) { + type = colon; + } + } + + part = memmem(after_sub_headers, request + request_len - after_sub_headers, boundary, boundary_len); + if (!part) { + fprintf(stderr, "Missing boundary after multipart payload\n"); + return FAILED; + } + part[-2] = 0; + part_len = part - after_sub_headers - 2; + part[0] = 0; + part += boundary_len; + + if (filename) { + uw_Basis_file f = {filename, type, {part_len, after_sub_headers}}; + + if (uw_set_file_input(ctx, name, f)) { + fprintf(stderr, "%s\n", uw_error_message(ctx)); + return FAILED; + } + } else if (uw_set_input(ctx, name, after_sub_headers)) { + fprintf(stderr, "%s\n", uw_error_message(ctx)); + return FAILED; + } + } + } + else { + if (is_post) + inputs = after_headers; + else if (inputs = strchr(path, '?')) + *inputs++ = 0; + + if (inputs) { + char *name, *value; + + while (*inputs) { + name = inputs; + if (inputs = strchr(inputs, '&')) + *inputs++ = 0; + else + inputs = strchr(name, 0); + + if (value = strchr(name, '=')) { + *value++ = 0; + if (uw_set_input(ctx, name, value)) { + fprintf(stderr, "%s\n", uw_error_message(ctx)); + return FAILED; + } + } + else if (uw_set_input(ctx, name, "")) { + fprintf(stderr, "%s\n", uw_error_message(ctx)); + return FAILED; + } + } + } + } + + printf("Serving URI %s....\n", path); + + while (1) { + size_t path_len = strlen(path); + + uw_write_header(ctx, "HTTP/1.1 200 OK\r\n"); + + if (path_len + 1 > rc->path_copy_size) { + rc->path_copy_size = path_len + 1; + rc->path_copy = realloc(rc->path_copy, rc->path_copy_size); + } + strcpy(rc->path_copy, path); + fk = uw_begin(ctx, rc->path_copy); + if (fk == SUCCESS || fk == RETURN_BLOB) { + uw_commit(ctx); + return SERVED; + } else if (fk == BOUNDED_RETRY) { + if (retries_left) { + printf("Error triggers bounded retry: %s\n", uw_error_message(ctx)); + --retries_left; + } + else { + printf("Fatal error (out of retries): %s\n", uw_error_message(ctx)); + + try_rollback(ctx); + + uw_reset_keep_error_message(ctx); + uw_write_header(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + uw_write_header(ctx, "Content-type: text/plain\r\n"); + uw_write(ctx, "Fatal error (out of retries): "); + uw_write(ctx, uw_error_message(ctx)); + uw_write(ctx, "\n"); + + return FAILED; + } + } else if (fk == UNLIMITED_RETRY) + printf("Error triggers unlimited retry: %s\n", uw_error_message(ctx)); + else if (fk == FATAL) { + printf("Fatal error: %s\n", uw_error_message(ctx)); + + try_rollback(ctx); + + uw_reset_keep_error_message(ctx); + uw_write_header(ctx, "HTTP/1.1 500 Internal Server Error\r\n"); + uw_write_header(ctx, "Content-type: text/html\r\n"); + uw_write(ctx, "<html><head><title>Fatal Error</title></head><body>"); + uw_write(ctx, "Fatal error: "); + uw_write(ctx, uw_error_message(ctx)); + uw_write(ctx, "\n</body></html>"); + + return FAILED; + } else { + printf("Unknown uw_handle return code!\n"); + + try_rollback(ctx); + + uw_reset_keep_request(ctx); + uw_write_header(ctx, "HTTP/1.1 500 Internal Server Error\n\r"); + uw_write_header(ctx, "Content-type: text/plain\r\n"); + uw_write(ctx, "Unknown uw_handle return code!\n"); + + return FAILED; + } + + if (try_rollback(ctx)) + return FAILED; + + uw_reset_keep_request(ctx); + } +} + +void *client_pruner(void *data) { + uw_context ctx = uw_request_new_context(); + + if (!ctx) + exit(1); + + while (1) { + uw_prune_clients(ctx); + sleep(5); + } +}