diff options
Diffstat (limited to 'libcli')
-rw-r--r-- | libcli/http/http.c | 309 | ||||
-rw-r--r-- | libcli/http/http_internal.h | 4 |
2 files changed, 293 insertions, 20 deletions
diff --git a/libcli/http/http.c b/libcli/http/http.c index 96c573a..6f22214 100644 --- a/libcli/http/http.c +++ b/libcli/http/http.c @@ -28,16 +28,28 @@ #undef strcasecmp +enum http_body_type { + BODY_NONE = 0, + BODY_CONTENT_LENGTH, + BODY_CHUNKED, + BODY_ERROR = -1 +}; + /** * Determines if a response should have a body. - * @return 1 if the response MUST have a body; 0 if the response MUST NOT have - * a body. Returns -1 on error. + * @return 2 if response MUST use chunked encoding, + * 1 if the response MUST have a body; + * 0 if the response MUST NOT have a body. + * Returns -1 on error. */ -static int http_response_needs_body(struct http_request *req) +static enum http_body_type http_response_needs_body( + struct http_request *req) { struct http_header *h = NULL; - if (!req) return -1; + if (!req) { + return BODY_ERROR; + } for (h = req->headers; h != NULL; h = h->next) { int cmp; @@ -45,6 +57,18 @@ static int http_response_needs_body(struct http_request *req) char c; unsigned long long v; + cmp = strcasecmp(h->key, "Transfer-Encoding"); + if (cmp == 0) { + cmp = strcasecmp(h->value, "chunked"); + if (cmp == 0) { + return BODY_CHUNKED; + } + /* unsupported Transfer-Encoding type */ + DBG_ERR("Unsupported transfer encoding type %s\n", + h->value); + return BODY_ERROR; + } + cmp = strcasecmp(h->key, "Content-Length"); if (cmp != 0) { continue; @@ -52,20 +76,25 @@ static int http_response_needs_body(struct http_request *req) n = sscanf(h->value, "%llu%c", &v, &c); if (n != 1) { - return -1; + return BODY_ERROR; } req->remaining_content_length = v; if (v != 0) { - return 1; + return BODY_CONTENT_LENGTH; } - return 0; + return BODY_NONE; } - return 0; + return BODY_NONE; } +struct http_chunk +{ + struct http_chunk *prev, *next; + DATA_BLOB blob; +}; struct http_read_response_state { enum http_parser_state parser_state; @@ -73,6 +102,7 @@ struct http_read_response_state { uint64_t max_content_length; DATA_BLOB buffer; struct http_request *response; + struct http_chunk *chunks; }; /** @@ -86,7 +116,7 @@ static enum http_read_status http_parse_headers(struct http_read_response_state char *key = NULL; char *value = NULL; int n = 0; - int ret; + enum http_body_type ret; /* Sanity checks */ if (!state || !state->response) { @@ -119,19 +149,24 @@ static enum http_read_status http_parse_headers(struct http_read_response_state ret = http_response_needs_body(state->response); switch (ret) { - case 1: + case BODY_CHUNKED: + DEBUG(11, ("%s: need to process chunks... %d\n", __func__, + state->response->response_code)); + state->parser_state = HTTP_READING_CHUNK_SIZE; + break; + case BODY_CONTENT_LENGTH: if (state->response->remaining_content_length <= state->max_content_length) { DEBUG(11, ("%s: Start of read body\n", __func__)); state->parser_state = HTTP_READING_BODY; break; } FALL_THROUGH; - case 0: + case BODY_NONE: DEBUG(11, ("%s: Skipping body for code %d\n", __func__, state->response->response_code)); state->parser_state = HTTP_READING_DONE; break; - case -1: + case BODY_ERROR: DEBUG(0, ("%s_: Error in http_response_needs_body\n", __func__)); TALLOC_FREE(line); return HTTP_DATA_CORRUPTED; @@ -162,6 +197,141 @@ error: return status; } +static bool http_response_process_chunks(struct http_read_response_state *state) +{ + struct http_chunk *chunk = NULL; + struct http_request *resp = state->response; + + for (chunk = state->chunks; chunk; chunk = chunk->next) { + DBG_DEBUG("processing chunk of size %zi\n", + chunk->blob.length); + if (resp->body.data == NULL) { + resp->body = chunk->blob; + chunk->blob = data_blob_null; + talloc_steal(resp, resp->body.data); + continue; + } + + resp->body.data = + talloc_realloc(resp, + resp->body.data, + uint8_t, + resp->body.length + chunk->blob.length); + if (!resp->body.data) { + return false; + } + memcpy(resp->body.data + resp->body.length, + chunk->blob.data, + chunk->blob.length); + + resp->body.length += chunk->blob.length; + + TALLOC_FREE(chunk->blob.data); + chunk->blob = data_blob_null; + } + return true; +} + +static enum http_read_status http_read_chunk_term(struct http_read_response_state *state) +{ + enum http_read_status status = HTTP_ALL_DATA_READ; + char *ptr = NULL; + char *line = NULL; + + /* Sanity checks */ + if (!state || !state->response) { + DBG_ERR("%s: Invalid Parameter\n", __func__); + return HTTP_DATA_CORRUPTED; + } + + line = talloc_strndup(state, (char *)state->buffer.data, state->buffer.length); + if (!line) { + DBG_ERR("%s: Memory error\n", __func__); + return HTTP_DATA_CORRUPTED; + } + ptr = strstr(line, "\r\n"); + if (ptr == NULL) { + TALLOC_FREE(line); + return HTTP_MORE_DATA_EXPECTED; + } + + if (strncmp(line, "\r\n", 2) == 0) { + /* chunk terminator */ + if (state->parser_state == HTTP_READING_FINAL_CHUNK_TERM) { + if (http_response_process_chunks(state) == false) { + status = HTTP_DATA_CORRUPTED; + goto out; + } + state->parser_state = HTTP_READING_DONE; + } else { + state->parser_state = HTTP_READING_CHUNK_SIZE; + } + status = HTTP_ALL_DATA_READ; + goto out; + } + + status = HTTP_DATA_CORRUPTED; +out: + TALLOC_FREE(line); + return status; +} + +static enum http_read_status http_read_chunk_size(struct http_read_response_state *state) +{ + enum http_read_status status = HTTP_ALL_DATA_READ; + char *ptr = NULL; + char *line = NULL; + char *value = NULL; + int n = 0; + unsigned long long v; + + /* Sanity checks */ + if (!state || !state->response) { + DBG_ERR("%s: Invalid Parameter\n", __func__); + return HTTP_DATA_CORRUPTED; + } + + line = talloc_strndup(state, (char *)state->buffer.data, state->buffer.length); + if (!line) { + DBG_ERR("%s: Memory error\n", __func__); + return HTTP_DATA_CORRUPTED; + } + ptr = strstr(line, "\r\n"); + if (ptr == NULL) { + TALLOC_FREE(line); + return HTTP_MORE_DATA_EXPECTED; + } + + n = sscanf(line, "%m[^\r\n]\r\n", &value); + if (n != 1) { + DBG_ERR("%s: Error parsing chunk size '%s'\n", __func__, line); + status = HTTP_DATA_CORRUPTED; + goto out; + } + + DBG_DEBUG("Got chunk size string %s\n", value); + n = sscanf(value, "%llx", &v); + if (n != 1) { + DBG_ERR("%s: Error parsing chunk size '%s'\n", __func__, line); + status = HTTP_DATA_CORRUPTED; + goto out; + } + DBG_DEBUG("Got chunk size %llu 0x%llx\n", v, v); + if (v == 0) { + state->parser_state = HTTP_READING_FINAL_CHUNK_TERM; + } else { + state->parser_state = HTTP_READING_CHUNK; + } + state->response->remaining_content_length = v; + status = HTTP_ALL_DATA_READ; +out: + if (value) { + free(value); + } + TALLOC_FREE(line); + return status; +} + /** * Parses the first line of a HTTP response */ @@ -301,6 +471,55 @@ static enum http_read_status http_read_body(struct http_read_response_state *sta return HTTP_ALL_DATA_READ; } +static enum http_read_status http_read_chunk(struct http_read_response_state *state) +{ + struct http_request *resp = state->response; + struct http_chunk *chunk = NULL; + size_t total = 0; + size_t prev = 0; + + if (state->buffer.length < resp->remaining_content_length) { + return HTTP_MORE_DATA_EXPECTED; + } + + for (chunk = state->chunks; chunk; chunk = chunk->next) { + total += chunk->blob.length; + } + + prev = total; + total = total + state->buffer.length; + if (total < prev) { + DBG_ERR("adding chunklen %zu to buf len %zu " + "will overflow\n", + state->buffer.length, + prev); + return HTTP_DATA_CORRUPTED; + } + if (total > state->max_content_length) { + DBG_DEBUG("size %zu exceeds " + "max content len %"PRIu64" skipping body\n", + total, + state->max_content_length); + state->parser_state = HTTP_READING_DONE; + goto out; + } + + /* chunk read */ + chunk = talloc_zero(state, struct http_chunk); + if (chunk == NULL) { + DBG_ERR("%s: Memory error\n", __func__); + return HTTP_DATA_CORRUPTED; + } + chunk->blob = state->buffer; + talloc_steal(chunk, chunk->blob.data); + DLIST_ADD_END(state->chunks, chunk); + state->parser_state = HTTP_READING_CHUNK_TERM; +out: + state->buffer = data_blob_null; + resp->remaining_content_length = 0; + return HTTP_ALL_DATA_READ; +} + static enum http_read_status http_read_trailer(struct http_read_response_state *state) { enum http_read_status status = HTTP_DATA_CORRUPTED; @@ -323,6 +542,16 @@ static enum http_read_status http_parse_buffer(struct http_read_response_state * case HTTP_READING_BODY: return http_read_body(state); break; + case HTTP_READING_FINAL_CHUNK_TERM: + case HTTP_READING_CHUNK_TERM: + return http_read_chunk_term(state); + break; + case HTTP_READING_CHUNK_SIZE: + return http_read_chunk_size(state); + break; + case HTTP_READING_CHUNK: + return http_read_chunk(state); + break; case HTTP_READING_TRAILER: return http_read_trailer(state); break; @@ -527,20 +756,60 @@ static int http_read_response_next_vector(struct tstream_context *stream, *_count = 1; } break; - case HTTP_MORE_DATA_EXPECTED: - /* TODO Optimize, allocating byte by byte */ - state->buffer.data = talloc_realloc(state, state->buffer.data, - uint8_t, state->buffer.length + 1); + case HTTP_MORE_DATA_EXPECTED: { + size_t toread = 1; + size_t total; + if (state->parser_state == HTTP_READING_BODY || + state->parser_state == HTTP_READING_CHUNK) { + struct http_request *resp = state->response; + toread = resp->remaining_content_length - + state->buffer.length; + } + + total = toread + state->buffer.length; + + if (total < state->buffer.length) { + DBG_ERR("adding %zu to buf len %zu " + "will overflow\n", + toread, + state->buffer.length); + return -1; + } + + /* + * test if content-length message exceeds the + * specified max_content_length + * Note: This check won't be hit at the moment + * due to an existing check in parse_headers + * which will skip the body. Check is here + * for completeness and to cater for future + * code changes. + */ + if (state->parser_state == HTTP_READING_BODY) { + if (total > state->max_content_length) { + DBG_ERR("content size %zu exceeds " + "max content len %"PRIu64"\n", + total, + state->max_content_length); + return -1; + } + } + + state->buffer.data = + talloc_realloc(state, state->buffer.data, + uint8_t, + state->buffer.length + toread); if (!state->buffer.data) { return -1; } - state->buffer.length++; + state->buffer.length += toread; vector[0].iov_base = (void *)(state->buffer.data + - state->buffer.length - 1); - vector[0].iov_len = 1; + state->buffer.length - toread); + vector[0].iov_len = toread; *_vector = vector; *_count = 1; break; + } case HTTP_DATA_CORRUPTED: case HTTP_REQUEST_CANCELED: case HTTP_DATA_TOO_LONG: @@ -603,7 +872,7 @@ static void http_read_response_done(struct tevent_req *subreq) { NTSTATUS status; struct tevent_req *req; - int ret; + enum http_body_type ret; int sys_errno; if (!subreq) { diff --git a/libcli/http/http_internal.h b/libcli/http/http_internal.h index ec17f7e..786ace6 100644 --- a/libcli/http/http_internal.h +++ b/libcli/http/http_internal.h @@ -28,6 +28,10 @@ enum http_parser_state { HTTP_READING_BODY, HTTP_READING_TRAILER, HTTP_READING_DONE, + HTTP_READING_CHUNK_SIZE, + HTTP_READING_CHUNK, + HTTP_READING_CHUNK_TERM, + HTTP_READING_FINAL_CHUNK_TERM, }; enum http_read_status { |