From 7e6d51a73cc3e46699424afb3ac33df1fe6ad539 Mon Sep 17 00:00:00 2001 From: Steve Holme Date: Wed, 5 Nov 2014 14:33:26 +0000 Subject: http_digest: Moved challenge decoding into SASL module --- lib/curl_sasl.c | 212 +++++++++++++++++++++++++++++++++++++++++++++++++++++- lib/curl_sasl.h | 4 ++ lib/http_digest.c | 192 ++----------------------------------------------- 3 files changed, 220 insertions(+), 188 deletions(-) (limited to 'lib') diff --git a/lib/curl_sasl.c b/lib/curl_sasl.c index ebb8d8153..3169730b5 100644 --- a/lib/curl_sasl.c +++ b/lib/curl_sasl.c @@ -19,6 +19,7 @@ * KIND, either express or implied. * * RFC2195 CRAM-MD5 authentication + * RFC2617 Basic and Digest Access Authentication * RFC2831 DIGEST-MD5 authentication * RFC4422 Simple Authentication and Security Layer (SASL) * RFC4616 PLAIN authentication @@ -57,15 +58,90 @@ extern void Curl_sasl_gssapi_cleanup(struct kerberos5data *krb5); #endif -#if !defined(CURL_DISABLE_CRYPTO_AUTH) && !defined(USE_WINDOWS_SSPI) +#if !defined(CURL_DISABLE_CRYPTO_AUTH) + +#if !defined(USE_WINDOWS_SSPI) #define DIGEST_QOP_VALUE_AUTH (1 << 0) #define DIGEST_QOP_VALUE_AUTH_INT (1 << 1) #define DIGEST_QOP_VALUE_AUTH_CONF (1 << 2) +#endif /* !USE_WINDOWS_SSPI */ #define DIGEST_QOP_VALUE_STRING_AUTH "auth" #define DIGEST_QOP_VALUE_STRING_AUTH_INT "auth-int" #define DIGEST_QOP_VALUE_STRING_AUTH_CONF "auth-conf" +#define DIGEST_MAX_VALUE_LENGTH 256 +#define DIGEST_MAX_CONTENT_LENGTH 1024 + +/* + * Return 0 on success and then the buffers are filled in fine. + * + * Non-zero means failure to parse. + */ +static int sasl_digest_get_pair(const char *str, char *value, char *content, + const char **endptr) +{ + int c; + bool starts_with_quote = FALSE; + bool escape = FALSE; + + for(c = DIGEST_MAX_VALUE_LENGTH - 1; (*str && (*str != '=') && c--); ) + *value++ = *str++; + *value=0; + + if('=' != *str++) + /* eek, no match */ + return 1; + + if('\"' == *str) { + /* this starts with a quote so it must end with one as well! */ + str++; + starts_with_quote = TRUE; + } + + for(c = DIGEST_MAX_CONTENT_LENGTH - 1; *str && c--; str++) { + switch(*str) { + case '\\': + if(!escape) { + /* possibly the start of an escaped quote */ + escape = TRUE; + *content++ = '\\'; /* even though this is an escape character, we still + store it as-is in the target buffer */ + continue; + } + break; + case ',': + if(!starts_with_quote) { + /* this signals the end of the content if we didn't get a starting + quote and then we do "sloppy" parsing */ + c=0; /* the end */ + continue; + } + break; + case '\r': + case '\n': + /* end of string */ + c=0; + continue; + case '\"': + if(!escape && starts_with_quote) { + /* end of string */ + c=0; + continue; + } + break; + } + escape = FALSE; + *content++ = *str; + } + *content=0; + + *endptr = str; + + return 0; /* all is fine! */ +} + +#if !defined(USE_WINDOWS_SSPI) /* Retrieves the value for a corresponding key from the challenge string * returns TRUE if the key could be found, FALSE if it does not exists */ @@ -122,7 +198,9 @@ static CURLcode sasl_digest_get_qop_values(const char *options, int *value) return CURLE_OK; } -#endif +#endif /* !USE_WINDOWS_SSPI */ + +#endif /* !CURL_DISABLE_CRYPTO_AUTH */ #if !defined(USE_WINDOWS_SSPI) /* @@ -582,6 +660,136 @@ CURLcode Curl_sasl_create_digest_md5_message(struct SessionHandle *data, } #endif /* !USE_WINDOWS_SSPI */ +/* + * Curl_sasl_decode_digest_http_message() + * + * This is used to decode a HTTP DIGEST challenge message into the seperate + * attributes. + * + * Parameters: + * + * chlg [in] - Pointer to the challenge message. + * digest [in/out] - The digest data struct being used and modified. + * + * Returns CURLE_OK on success. + */ +CURLcode Curl_sasl_decode_digest_http_message(const char *chlg, + struct digestdata *digest) +{ + bool before = FALSE; /* got a nonce before */ + bool foundAuth = FALSE; + bool foundAuthInt = FALSE; + char *token = NULL; + char *tmp = NULL; + + /* If we already have received a nonce, keep that in mind */ + if(digest->nonce) + before = TRUE; + + /* Clean up any former leftovers and initialise to defaults */ + Curl_sasl_digest_cleanup(digest); + + for(;;) { + char value[DIGEST_MAX_VALUE_LENGTH]; + char content[DIGEST_MAX_CONTENT_LENGTH]; + + /* Extract a value=content pair */ + if(!sasl_digest_get_pair(chlg, value, content, &chlg)) { + if(Curl_raw_equal(value, "nonce")) { + digest->nonce = strdup(content); + if(!digest->nonce) + return CURLE_OUT_OF_MEMORY; + } + else if(Curl_raw_equal(value, "stale")) { + if(Curl_raw_equal(content, "true")) { + digest->stale = TRUE; + digest->nc = 1; /* we make a new nonce now */ + } + } + else if(Curl_raw_equal(value, "realm")) { + digest->realm = strdup(content); + if(!digest->realm) + return CURLE_OUT_OF_MEMORY; + } + else if(Curl_raw_equal(value, "opaque")) { + digest->opaque = strdup(content); + if(!digest->opaque) + return CURLE_OUT_OF_MEMORY; + } + else if(Curl_raw_equal(value, "qop")) { + char *tok_buf; + /* Tokenize the list and choose auth if possible, use a temporary + clone of the buffer since strtok_r() ruins it */ + tmp = strdup(content); + if(!tmp) + return CURLE_OUT_OF_MEMORY; + + token = strtok_r(tmp, ",", &tok_buf); + while(token != NULL) { + if(Curl_raw_equal(token, DIGEST_QOP_VALUE_STRING_AUTH)) { + foundAuth = TRUE; + } + else if(Curl_raw_equal(token, DIGEST_QOP_VALUE_STRING_AUTH_INT)) { + foundAuthInt = TRUE; + } + token = strtok_r(NULL, ",", &tok_buf); + } + + free(tmp); + + /* Select only auth o auth-int. Otherwise, ignore */ + if(foundAuth) { + digest->qop = strdup(DIGEST_QOP_VALUE_STRING_AUTH); + if(!digest->qop) + return CURLE_OUT_OF_MEMORY; + } + else if(foundAuthInt) { + digest->qop = strdup(DIGEST_QOP_VALUE_STRING_AUTH_INT); + if(!digest->qop) + return CURLE_OUT_OF_MEMORY; + } + } + else if(Curl_raw_equal(value, "algorithm")) { + digest->algorithm = strdup(content); + if(!digest->algorithm) + return CURLE_OUT_OF_MEMORY; + + if(Curl_raw_equal(content, "MD5-sess")) + digest->algo = CURLDIGESTALGO_MD5SESS; + else if(Curl_raw_equal(content, "MD5")) + digest->algo = CURLDIGESTALGO_MD5; + else + return CURLE_BAD_CONTENT_ENCODING; + } + else { + /* unknown specifier, ignore it! */ + } + } + else + break; /* we're done here */ + + /* Pass all additional spaces here */ + while(*chlg && ISSPACE(*chlg)) + chlg++; + + /* Allow the list to be comma-separated */ + if(',' == *chlg) + chlg++; + } + + /* We had a nonce since before, and we got another one now without + 'stale=true'. This means we provided bad credentials in the previous + request */ + if(before && !digest->stale) + return CURLE_BAD_CONTENT_ENCODING; + + /* We got this header without a nonce, that's a bad Digest line! */ + if(!digest->nonce) + return CURLE_BAD_CONTENT_ENCODING; + + return CURLE_OK; +} + /* * Curl_sasl_digest_cleanup() * diff --git a/lib/curl_sasl.h b/lib/curl_sasl.h index 8fcce320f..da6511c3d 100644 --- a/lib/curl_sasl.h +++ b/lib/curl_sasl.h @@ -105,6 +105,10 @@ CURLcode Curl_sasl_create_digest_md5_message(struct SessionHandle *data, const char *service, char **outptr, size_t *outlen); +/* This is used to decode a HTTP DIGEST challenge message */ +CURLcode Curl_sasl_decode_digest_http_message(const char *chlg, + struct digestdata *digest); + /* This is used to clean up the digest specific data */ void Curl_sasl_digest_cleanup(struct digestdata *digest); #endif diff --git a/lib/http_digest.c b/lib/http_digest.c index d2dbfe59b..19e7c8392 100644 --- a/lib/http_digest.c +++ b/lib/http_digest.c @@ -42,77 +42,6 @@ /* The last #include file should be: */ #include "memdebug.h" -#define MAX_VALUE_LENGTH 256 -#define MAX_CONTENT_LENGTH 1024 - -/* - * Return 0 on success and then the buffers are filled in fine. - * - * Non-zero means failure to parse. - */ -static int get_pair(const char *str, char *value, char *content, - const char **endptr) -{ - int c; - bool starts_with_quote = FALSE; - bool escape = FALSE; - - for(c=MAX_VALUE_LENGTH-1; (*str && (*str != '=') && c--); ) - *value++ = *str++; - *value=0; - - if('=' != *str++) - /* eek, no match */ - return 1; - - if('\"' == *str) { - /* this starts with a quote so it must end with one as well! */ - str++; - starts_with_quote = TRUE; - } - - for(c=MAX_CONTENT_LENGTH-1; *str && c--; str++) { - switch(*str) { - case '\\': - if(!escape) { - /* possibly the start of an escaped quote */ - escape = TRUE; - *content++ = '\\'; /* even though this is an escape character, we still - store it as-is in the target buffer */ - continue; - } - break; - case ',': - if(!starts_with_quote) { - /* this signals the end of the content if we didn't get a starting - quote and then we do "sloppy" parsing */ - c=0; /* the end */ - continue; - } - break; - case '\r': - case '\n': - /* end of string */ - c=0; - continue; - case '\"': - if(!escape && starts_with_quote) { - /* end of string */ - c=0; - continue; - } - break; - } - escape = FALSE; - *content++ = *str; - } - *content=0; - - *endptr = str; - - return 0; /* all is fine! */ -} - /* Test example headers: WWW-Authenticate: Digest realm="testrealm", nonce="1053604598" @@ -125,12 +54,7 @@ CURLcode Curl_input_digest(struct connectdata *conn, const char *header) /* rest of the *-authenticate: header */ { - char *token = NULL; - char *tmp = NULL; - bool foundAuth = FALSE; - bool foundAuthInt = FALSE; struct SessionHandle *data=conn->data; - bool before = FALSE; /* got a nonce before */ struct digestdata *d; if(proxy) { @@ -140,118 +64,14 @@ CURLcode Curl_input_digest(struct connectdata *conn, d = &data->state.digest; } - if(checkprefix("Digest", header)) { - header += strlen("Digest"); - - /* If we already have received a nonce, keep that in mind */ - if(d->nonce) - before = TRUE; - - /* clear off any former leftovers and init to defaults */ - Curl_sasl_digest_cleanup(d); - - for(;;) { - char value[MAX_VALUE_LENGTH]; - char content[MAX_CONTENT_LENGTH]; - - while(*header && ISSPACE(*header)) - header++; - - /* extract a value=content pair */ - if(!get_pair(header, value, content, &header)) { - if(Curl_raw_equal(value, "nonce")) { - d->nonce = strdup(content); - if(!d->nonce) - return CURLE_OUT_OF_MEMORY; - } - else if(Curl_raw_equal(value, "stale")) { - if(Curl_raw_equal(content, "true")) { - d->stale = TRUE; - d->nc = 1; /* we make a new nonce now */ - } - } - else if(Curl_raw_equal(value, "realm")) { - d->realm = strdup(content); - if(!d->realm) - return CURLE_OUT_OF_MEMORY; - } - else if(Curl_raw_equal(value, "opaque")) { - d->opaque = strdup(content); - if(!d->opaque) - return CURLE_OUT_OF_MEMORY; - } - else if(Curl_raw_equal(value, "qop")) { - char *tok_buf; - /* tokenize the list and choose auth if possible, use a temporary - clone of the buffer since strtok_r() ruins it */ - tmp = strdup(content); - if(!tmp) - return CURLE_OUT_OF_MEMORY; - - token = strtok_r(tmp, ",", &tok_buf); - while(token != NULL) { - if(Curl_raw_equal(token, "auth")) { - foundAuth = TRUE; - } - else if(Curl_raw_equal(token, "auth-int")) { - foundAuthInt = TRUE; - } - token = strtok_r(NULL, ",", &tok_buf); - } - free(tmp); - /*select only auth o auth-int. Otherwise, ignore*/ - if(foundAuth) { - d->qop = strdup("auth"); - if(!d->qop) - return CURLE_OUT_OF_MEMORY; - } - else if(foundAuthInt) { - d->qop = strdup("auth-int"); - if(!d->qop) - return CURLE_OUT_OF_MEMORY; - } - } - else if(Curl_raw_equal(value, "algorithm")) { - d->algorithm = strdup(content); - if(!d->algorithm) - return CURLE_OUT_OF_MEMORY; - - if(Curl_raw_equal(content, "MD5-sess")) - d->algo = CURLDIGESTALGO_MD5SESS; - else if(Curl_raw_equal(content, "MD5")) - d->algo = CURLDIGESTALGO_MD5; - else - return CURLE_BAD_CONTENT_ENCODING; - } - else { - /* unknown specifier, ignore it! */ - } - } - else - break; /* we're done here */ - - /* pass all additional spaces here */ - while(*header && ISSPACE(*header)) - header++; - if(',' == *header) - /* allow the list to be comma-separated */ - header++; - } - /* We had a nonce since before, and we got another one now without - 'stale=true'. This means we provided bad credentials in the previous - request */ - if(before && !d->stale) - return CURLE_BAD_CONTENT_ENCODING; - - /* We got this header without a nonce, that's a bad Digest line! */ - if(!d->nonce) - return CURLE_BAD_CONTENT_ENCODING; - } - else - /* else not a digest, get out */ + if(!checkprefix("Digest", header)) return CURLE_BAD_CONTENT_ENCODING; - return CURLE_OK; + header += strlen("Digest"); + while(*header && ISSPACE(*header)) + header++; + + return Curl_sasl_decode_digest_http_message(header, d); } /* convert md5 chunk to RFC2617 (section 3.1.3) -suitable ascii string*/ -- cgit v1.2.3