下载的文件约有800KB，但是单片机内存没有那么大，
程序用的是示例程序
webclient_file.c
MBEDTLS的内存最大增到过最大限制长度16384，但是还是原因mbedtls的大小，小于下载文件大小导致失败
//#define MBEDTLS_SSL_MAX_CONTENT_LEN 16384
#define MBEDTLS_AES_ROM_TABLES#define MBEDTLS_ECP_WINDOW_SIZE 2#define MBEDTLS_SSL_MAX_CONTENT_LEN 3584*2
每次读文件的大小都限制了2048字节
#define WEBCLIENT_HEADER_BUFSZ 2048#define WEBCLIENT_RESPONSE_BUFSZ 2048
下载失败日志如下:
下载失败日志如下:
[D/mbedtls.clnt] Set debug level (1)[D/mbedtls.clnt] mbedtls client struct init success...[D/web] host address: unilink-uat.crland.com.cn , port: 443[D/mbedtls.clnt] mbedtls client context init success...[D/mbedtls.clnt] Connected unilink-uat.crland.com.cn:443 success...[D/mbedtls.clnt] Certificate verified success...[D/web] request header:[D/web] GET /uat-api/file/I5MaXMTfXiI2M-JhmfNFz4_LPSeuvsvh?accessKey=I5MaXMV7JBd2Nr2wmoy_ysqmVJn1u9_t HTTP/1.1[D/web] Host: unilink-uat.crland.com.cn[D/web] User-Agent: RT-Thread HTTP Agent[D/web] response header:[D/web] HTTP/1.1 200 OK[D/web] Date: Thu, 14 Nov 2024 12:00:51 GMT[D/web] Content-Type: application/octet-stream[D/web] Content-Length: 738482[D/web] Connection: keep-alive[D/web] traceparent: 00-932a8c34cba8dcb89c2e97c565f81768-70bc13c3e3b97d2d-01[D/web] Vary: Origin[D/web] Vary: Access-Control-Request-Method[D/web] Vary: Access-Control-Request-Headers[D/web] traceparent: 00-932a8c34cba8dcb89c2e97c565f81768-0f4e5e5146cc9664-01[D/web] Vary: Origin[D/web] Vary: Access-Control-Request-Method[D/web] Vary: Access-Control-Request-Headers[D/web] Accept-Ranges: bytes[D/web] Content-MD5: 288bbbefb2e7adba49bee0408df74757[D/web] Digest: sha-256=459e9106a46221589d5ceb6eac43920f08ccefb3c9d080c74d7cb189261a8c97[D/web] Content-Disposition: attachment; filename*=UTF-8''EACSS_HD_HR_4.0.0.4.bin[D/web] get position handle response(200).[D/web.file] len:2048>[D/web.file] len:4096>[D/web.file] len:6144>[D/web.file] len:8192>[D/web.file] len:10240>[D/web.file] len:12288>[D/web.file] len:14336>[D/web.file] len:16384>[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:1897: requesting more data than fits[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:4719: mbedtls_ssl_fetch_input() returned -28928 (-0x7100)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:3974: ssl_get_next_record() returned -28928 (-0x7100)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:5464: mbedtls_ssl_read_record() returned -28928 (-0x7100)[E/mbedtls.clnt] mbedtls_client_read data error, return -0x7100[D/web] receive data error(-28928).[D/web.file] len:16942>[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:1897: requesting more data than fits[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:4719: mbedtls_ssl_fetch_input() returned -28928 (-0x7100)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:3974: ssl_get_next_record() returned -28928 (-0x7100)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:5464: mbedtls_ssl_read_record() returned -28928 (-0x7100)[E/mbedtls.clnt] mbedtls_client_read data error, return -0x7100[D/web] receive data error(-28928).[D/web.file] read err[D/web.file] save 16942 bytes.[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:2866: mbedtls_ssl_flush_output() returned -26752 (-0x6880)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:5000: mbedtls_ssl_write_record() returned -26752 (-0x6880)[D/mbedtls.clnt] ../packages/mbedtls-latest/mbedtls/library/ssl_msg.c:5871: mbedtls_ssl_send_alert_message() returned -26752 (-0x6880)
下面是mbedtls源码，nb_want的值是一直增加的是随着webclient_read一直增加的，这样子内存一直不够。
int mbedtls_ssl_fetch_input( mbedtls_ssl_context *ssl, size_t nb_want ){ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; size_t len;#if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) size_t in_buf_len = ssl->in_buf_len;#else size_t in_buf_len = MBEDTLS_SSL_IN_BUFFER_LEN;#endif MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> fetch input" ) ); if( ssl->f_recv == NULL && ssl->f_recv_timeout == NULL ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "Bad usage of mbedtls_ssl_set_bio() " "or mbedtls_ssl_set_bio()" ) ); return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); } if( nb_want > in_buf_len - (size_t)( ssl->in_hdr - ssl->in_buf ) ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "requesting more data than fits" ) ); return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA ); }#if defined(MBEDTLS_SSL_PROTO_DTLS) if( ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM ) { uint32_t timeout; /* * The point is, we need to always read a full datagram at once, so we * sometimes read more then requested, and handle the additional data. * It could be the rest of the current record (while fetching the * header) and/or some other records in the same datagram. */ /* * Move to the next record in the already read datagram if applicable */ if( ssl->next_record_offset != 0 ) { if( ssl->in_left < ssl->next_record_offset ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); } ssl->in_left -= ssl->next_record_offset; if( ssl->in_left != 0 ) { MBEDTLS_SSL_DEBUG_MSG( 2, ( "next record in same datagram, offset: %" MBEDTLS_PRINTF_SIZET, ssl->next_record_offset ) ); memmove( ssl->in_hdr, ssl->in_hdr + ssl->next_record_offset, ssl->in_left ); } ssl->next_record_offset = 0; } MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %" MBEDTLS_PRINTF_SIZET ", nb_want: %" MBEDTLS_PRINTF_SIZET, ssl->in_left, nb_want ) ); /* * Done if we already have enough data. */ if( nb_want <= ssl->in_left) { MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= fetch input" ) ); return( 0 ); } /* * A record can't be split across datagrams. If we need to read but * are not at the beginning of a new record, the caller did something * wrong. */ if( ssl->in_left != 0 ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) ); return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); } /* * Don't even try to read if time's out already. * This avoids by-passing the timer when repeatedly receiving messages * that will end up being dropped. */ if( mbedtls_ssl_check_timer( ssl ) != 0 ) { MBEDTLS_SSL_DEBUG_MSG( 2, ( "timer has expired" ) ); ret = MBEDTLS_ERR_SSL_TIMEOUT; } else { len = in_buf_len - ( ssl->in_hdr - ssl->in_buf ); if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER ) timeout = ssl->handshake->retransmit_timeout; else timeout = ssl->conf->read_timeout; MBEDTLS_SSL_DEBUG_MSG( 3, ( "f_recv_timeout: %lu ms", (unsigned long) timeout ) ); if( ssl->f_recv_timeout != NULL ) ret = ssl->f_recv_timeout( ssl->p_bio, ssl->in_hdr, len, timeout ); else ret = ssl->f_recv( ssl->p_bio, ssl->in_hdr, len ); MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_recv(_timeout)", ret ); if( ret == 0 ) return( MBEDTLS_ERR_SSL_CONN_EOF ); } if( ret == MBEDTLS_ERR_SSL_TIMEOUT ) { MBEDTLS_SSL_DEBUG_MSG( 2, ( "timeout" ) ); mbedtls_ssl_set_timer( ssl, 0 ); if( ssl->state != MBEDTLS_SSL_HANDSHAKE_OVER ) { if( ssl_double_retransmit_timeout( ssl ) != 0 ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "handshake timeout" ) ); return( MBEDTLS_ERR_SSL_TIMEOUT ); } if( ( ret = mbedtls_ssl_resend( ssl ) ) != 0 ) { MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_resend", ret ); return( ret ); } return( MBEDTLS_ERR_SSL_WANT_READ ); }#if defined(MBEDTLS_SSL_SRV_C) && defined(MBEDTLS_SSL_RENEGOTIATION) else if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER && ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_PENDING ) { if( ( ret = mbedtls_ssl_resend_hello_request( ssl ) ) != 0 ) { MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_resend_hello_request", ret ); return( ret ); } return( MBEDTLS_ERR_SSL_WANT_READ ); }#endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_RENEGOTIATION */ } if( ret < 0 ) return( ret ); ssl->in_left = ret; } else#endif { MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %" MBEDTLS_PRINTF_SIZET ", nb_want: %" MBEDTLS_PRINTF_SIZET, ssl->in_left, nb_want ) ); while( ssl->in_left < nb_want ) { len = nb_want - ssl->in_left; if( mbedtls_ssl_check_timer( ssl ) != 0 ) ret = MBEDTLS_ERR_SSL_TIMEOUT; else { if( ssl->f_recv_timeout != NULL ) { ret = ssl->f_recv_timeout( ssl->p_bio, ssl->in_hdr + ssl->in_left, len, ssl->conf->read_timeout ); } else { ret = ssl->f_recv( ssl->p_bio, ssl->in_hdr + ssl->in_left, len ); } } MBEDTLS_SSL_DEBUG_MSG( 2, ( "in_left: %" MBEDTLS_PRINTF_SIZET ", nb_want: %" MBEDTLS_PRINTF_SIZET, ssl->in_left, nb_want ) ); MBEDTLS_SSL_DEBUG_RET( 2, "ssl->f_recv(_timeout)", ret ); if( ret == 0 ) return( MBEDTLS_ERR_SSL_CONN_EOF ); if( ret < 0 ) return( ret ); if ( (size_t)ret > len || ( INT_MAX > SIZE_MAX && ret > (int)SIZE_MAX ) ) { MBEDTLS_SSL_DEBUG_MSG( 1, ( "f_recv returned %d bytes but only %" MBEDTLS_PRINTF_SIZET " were requested", ret, len ) ); return( MBEDTLS_ERR_SSL_INTERNAL_ERROR ); } ssl->in_left += ret; } } MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= fetch input" ) ); return( 0 );}
尝试过写个简单的断点续传的程序，还是报同样的错误。
请问各位大佬有什么头绪解决这个问题，或者说mbedtls是不是还有些参数可以配置，
怎么修改webclient_read，让mbedtls_ssl_fetch_input中的nb_want不会一直增加下去？
硬件上有AES和RSA不？看看能不能用起来。
也可以看看服务器上面是否支持对低算力CPU更友好的加密算法，如chacha20这类
另外，使用 http1.1 keepalive 或 http2.0 可以减少握手次数。